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A study was conducted to evaluate the effect of an emulsifier on reduced-energy diets using two fat sources for broilers. The study was designed as a 2 x 3 factorial arrangement of treatments. The first factor was 2 fat sources (poultry fat or beef tallow). The second factor was a basal diet with the recommended energy levels, a diet with a 0.83 MJ/kg of energy reduction, and a diet with an energy reduction and inclusion of 1 g emulsifier/kg of diet. The emulsifier used in this study was composed of soy lecithin and polyethylene glycol ricinoleate. The emulsifier increased apparent metabolizable energy (AME) and apparent metabolizable energy corrected for nitrogen balance (AMEn) in beef tallow diets compared to energy-reduced diets (P

We present a study on the formation of silver (Ag) and bimetallic silver-gold (AgAu) nanoparticles monitored by in situ SAXS as well as by ex situ TEM, XRD and UV-vis analysis in a flow reactor at controlled reaction temperature. The formation mechanism of the nanoparticles is derived from the structural parameters obtained from the experimental data. The evolution of the average particle size of pure and alloyed nanoparticles shows that the particle growth occurs initially by a coalescence mechanism. The later growth of pure silver nanoparticles is well described by Ostwald ripening and for the alloyed nanoparticles by a process with a significantly slower growth rate. Additionally, the SAXS data of pure silver nanoparticles revealed two major populations of nanoparticles, the first one with a continuous crystal growth to a saturation plateau, and the second one probably with a continuous emergence of small new crystals. The particle sizes obtained by SAXS agree well with the results from transmission electron microscopy and X-ray diffraction. The present study demonstrates the capability of an in situ investigation of synthesis processes using a laboratory based SAXS instrument. Online monitoring of the synthesis permitted a detailed investigation of the structural evolution of the system. CA - Epple

Las bacterias han sido reconocidas como el principal factor etiológico en el desarrollo de las enfermedades pulpares y periapicales. El objetivo del tratamiento de conductos es prevenir o curar la periodontitis apical. Parte del éxito de la endodoncia va a depender de la eliminación del tejido pulpar, tanto vital como necrótico, que se encuentra situado dentro del sistema de conductos radiculares. Los irrigantes que se utilizan en endodoncia deberían tener la capacidad de disolver los remanentes pulpares, ya que la remoción del tejido pulpar únicamente con la instrumentación mecánica es insuficiente debido a la compleja morfología de los sistemas de conductos. El hipoclorito sódico (NaOCl) es recomendado como principal irrigante por su capacidad antimicrobiana, para prevenir la formación de barrillo dentinario y disolver su parte orgánica, así como la disolución de tejido orgánico remanente. La literatura indica que no existe el irrigante ideal y para cumplir con los objetivos de la irrigación debemos combinar el uso de hipoclorito sódico con el de otros irrigantes. La combinación de sustancias irrigadoras más empleada es hipoclorito sódico y EDTA como agente quelante. La bibliografía estudiada expone que el tiempo y el volumen son dos factores importantes que afectan a la capacidad de deglutir tejido orgánico del hipoclorito sódico. El objetivo de este trabajo fue comparar la capacidad de disolver tejido orgánico del hipoclorito sódico como agente único de irrigación respecto a la combinación de Keratobacter® e hipoclorito sódico. De esta forma valoraremos las aplicaciones clínicas que se pueden obtener de esta combinación de soluciones irrigadoras y así crear unas pautas efectivas para mejorar la disolución de tejido orgánico en la terapia endodóntica. Odontología

Incluye tablas y figuras. El control de arvenses en las explotaciones agrícolas tropicales es de suma importancia ya que estas especies limitan la productividad, pues compiten de forma directa por nutrientes, espacios vitales y luminosidad, llegando a ser dentro de la agricultura a gran escala convencional el rubro de agroquímicos más costoso, del cual se sabe datos como que para el 2018 en Colombia se movilizó us$600 millones en agroquímicos que pesan un 35% de los costos de totales de la producción de los cultivos, y a su vez un 59% de este valor lo constituyen los herbicidas. El mercado nacional ha ofrecido durante años a los agricultores numerosas opciones de agroquímicos para el manejo de arvenses, estas a su vez han sido adoptadas de forma masiva por los agricultores y con el paso de los años algunos ingredientes activos (IA) fueron perdiendo la capacidad de control en algunas especies, a esto se le conoce como una resistencia, en la actualidad se encuentran registradas numerosas especies que presentan resistencia a diferentes ingredientes activos como es el caso de echinocloa colonum resistente al propanil entre otras, un ejemplo más es el conocido glifosato que se introdujo al mercado en el año 1994 y 22 años después, en 1996 se informó el primer caso de resistencia en el continente a glifosato en lolium rigidum. (Villaba, 2009) En el presente trabajo el objeto de estudio es una especie conocida como asystacia sp que ha presentado resistencia al herbicida glifosato 480, esta especie se ha presentado en medio de los cultivos de cítricos, aguacate y piña donde ha cobrado importancia económica ya que compite con los cultivos establecidos e incrementa el rubro de los manejos de arvenses, en este trabajo se plantea las hipótesis de manejo de arvenses con el herbicida mencionado en combinación con cuatro diferentes surfactantes y se compara su efecto con el de dos herbicidas más conocidos como glufosinato de amonio y paraquat también en combinación con cuatro surfactantes en pre siembra. The control of weeds in tropical farms is of the utmost importance since these species limit productivity, since they compete directly for nutrients, vital spaces and light, becoming the most important agrochemical category in conventional large-scale agriculture. expensive, of which data is known such as that for 2018 in Colombia US$600 million in agrochemicals were mobilized that weigh 35% of the total costs of crop production, and in turn 59% of this value is constituted by the herbicides. For years, the national market has offered farmers numerous agrochemical options for weed management, these in turn have been massively adopted by farmers and over the years some active ingredients (AI) have been losing their ability to of control in some species, this is known as a resistance, at present numerous species are registered that present resistance to different active ingredients such as the case of echinocloa colonum resistant to propanil among others, one more example is the well-known glyphosate which was introduced to the market in 1994 and 22 years later, in 1996, the first case of resistance to glyphosate in lolium rigidum was reported on the continent. (Villaba, 2009) In the present work the object of study is a species known as asystacia sp that has presented resistance to the herbicide glyphosate 480, this species has appeared in the middle of citrus, avocado and pineapple crops where it has gained economic importance since it competes with the established crops and increases the heading of weed management, in this work the hypotheses of weed management with the aforementioned herbicide in combination with four different surfactants are proposed and its effect is compared with that of two better-known herbicides such as glufosinate ammonium and paraquat also in combination with four surfactants in pre-sowing. Dedicatoria. – Agradecimientos. – Resumen. – Abstract. -- Planteamiento Del Problema. – Introducción. – Objetivo. -- Objetivo general (Og). -- Objetivos Específicos (Oe). -- Marco Teórico. -- Taxonomía Del Asystasia Sp. -- Morfología De La Planta. --Sustancias Químicas. – Glifosato. – Paraquat. -- Glufisano De Amonio. – Surfactantes. -- Inex-A. – Fasten. – Siliconado. -- Materiales Y Métodos. – Materiales. – Métodos. -- Diseño Experimental. -- Resultados Y Discusión. – Conclusiones. Pregrado Ingeniero(a) Agrónomo(a) Ingeniería Agronómica

Orientador: Watson Loh Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química Resumo: Este trabalho apresenta o estudo do comportamento de fases de complexos eletrostáticos formados pela associação de polímeros com surfactantes e polímeros de carga oposta sob o efeito de sais inorgânicos. Utilizou-se o poli(acrilato) de massas molares 2 e 450 kDa com o surfactante catiônico dodeciltrimetilamônio na presença dos sais NaBr ou NaCl. Para concentrações de complexos em torno de 20% m/m, constatou-se que duas separações de fase importantes ocorrem: a separação associativa, onde polímero e surfactante permanecem na mesma fase, e a separação segregativa onde essas espécies se concentram em fases distintas. Os agregados de surfactante se encontram inicialmente empacotados em uma estrutura cúbica micelar que transita para uma fase micelar, que por sua vez, pode alterar seu tamanho e forma à medida que a concentração de sal aumenta. Para concentrações de complexos em torno de 50% m/m, o sistema é monofásico com agregados de surfactante em um arranjo hexagonal ou cúbico micelar. O aumento na concentração de sal faz com que todos os agregados se tornem mesofases hexagonais. Além disso, uma nova separação de fases ocorre, gerando uma fase rica no surfactante com estrutura hexagonal e uma fase aquosa que vai ficando rica no polímero em maiores concentrações de sal. Complexos de poli(acrilato), com massas molares 2 e 100 kDa e o policátion poli(dialildimetilamônio) também foram preparados e estudados na presença de NaCl e Na2SO4. Para estes complexos, também se observa as separações de fase associativa e segregativa nos sistemas contendo NaCl, mas não se observa a separação segregativa nos sistemas com Na2SO4. Análises das fases nos sistemas segregados por NaCl não somente constataram que os polímeros sofrem forte segregação, mas que também que os contraíons pequenos particionam entre as fases. Cada contraíon pequeno se concentra na fase que é mais rica no seu respectivo poliíon de carga oposta. As interações entre polímeros de carga oposta também foram estudadas através de simulações de Monte Carlo. Aplicou-se um potencial coulômbico de blindagem a fim de simular a presença do sal, cuja concentração foi parametrizada através do comprimento de blindagem (?D). Em altos valores de ?D, os polímeros tendem a se associar. Essa associação tende a enfraquecer à medida que ?D diminui. Em valores mais baixos de ?D, os polímeros tendem a se segregar. Por último, estudou-se experimentalmente o efeito de diferentes grupos carregados dos polímeros frente à seletividade de complexação. Constatou-se que o sulfonato tem preferência a ser complexado em relação ao carboxilato e que o amônio quaternário é preferível à complexação ao amônio primário. Esses sistemas também mostram a formação de complexos multifásicos Abstract: This work presents the study of the phase behavior of electrostatic complexes formed by the association of polymers and oppositely charged surfactants and polymers upon addition of inorganic salts. Poly(acrylate) with molar masses of 2 and 450 kDa were used with the cationic surfactant dodecyltrimethylammonium in the presence of NaBr or NaCl. For concentrations of complexes around 20 wt%, two important phase separation events were observed: associative phase separation, where polymer and surfactant remain in the same phase, and segregative phase separation, where both species are concentrated in different phases. Surfactant aggregates are initially packed in a cubic micellar structure that undergoes a transition to a micellar phase, which can change its size and shape as the salt concentration increases. For complex concentrations around 50 wt%, the systems present a single-phase with surfactant aggregates in a hexagonal or cubic micellar arrangement. The increase in the salt concentration causes all aggregates to form a hexagonal phase. Upon further addition, a new phase separation occurs, generating a surfactant-rich phase with a hexagonal structure and an aqueous phase that becomes polymer-rich at higher salt concentrations. Poly(acrylate) complexes with molar masses of 2 and 100 kDa and the polycation poly(diallyldimethylammonium) were also prepared and studied in the presence of NaCl and Na2SO4. For these complexes, associative and segregative phase separations are also observed in systems containing NaCl, but segregative separation is not observed in systems with Na2SO4. Phase analyses in NaCl-segregated systems not only found that polymers undergo strong segregation, but also that the small counterions partition between the phases. Each small ion concentrates on the phase that is the richest in its oppositely charged poly-ion. The interactions between oppositely charged polymers were also studied through Monte Carlo simulations. The screening Coulomb potential was applied in order to simulate the presence of a salt, whose concentrations were parameterized through the screening length (?D). We have found that at higher values of ?D, polymers tend to associate. This association tends to weaken as ?D decreases. On the other hand, at lower values of ?D, polymers tend to segregate. Finally, the effect of different charged groups from the polymers on the complexation selectivity was studied experimentally. We have verified that the sulfonate complexes preferentially over the carboxylate group, while that quaternary ammonium binds more favorably than primary ammonium groups. These systems also form multiphasic complexes Doutorado Físico-Química Doutor em Ciências FAPESP 2018/09099-3 CNPQ 140623/2018-3

Os detergentes de lavagem manual de loiça são produtos químicos, muito utilizados no nosso quotidiano, para limpeza e higienização de uma grande variedade de superfícies, de forma rápida e eficaz. Estes detergentes possuem caraterísticas físico-químicas, tais como pH e viscosidade que determinam a sua qualidade e, como tal, necessitam de monitorização e controlo durante o processo de produção. Alguns dos detergentes de lavagem manual de loiça produzidos pela empresa Mistolin apresentam uma viscosidade crescente ao longo do seu tempo de vida útil, traduzindo-se em reclamações dos consumidores quanto à consistência e consequente dificuldade de manuseamento dos referidos produtos. Por este motivo, surgiu a necessidade de avaliar o comportamento de cinco diferentes formulações de detergentes lava-loiça, tanto concentrados como diluídos, relativamente aos parâmetros de viscosidade e pH, para diferentes temperaturas de armazenamento, de modo a mimetizar possíveis condições extremas de acondicionamento dos produtos após expedição para o mercado. Durante oito semanas foram feitas medições de pH e viscosidade para cada uma das formulações em estudo para diferentes temperaturas de armazenamento nomeadamente, a 4, 25 e 40 oC. Verificou-se que o pH das formulações, com exceção da formulação designada por D2, varia dentro de um intervalo estipulado para cada detergente, e que independentemente da temperatura de armazenamento, as formulações são estáveis quanto ao parâmetro de pH. Relativamente à viscosidade, este parâmetro aumenta ao longo do tempo para a temperatura de armazenamento de 40 ºC, para todas as formulações com exceção de uma (formulação D2), dando a indicação que o uso de diferentes misturas de tensioativos nas formulações, bem como a sua concentração e o aumento da temperatura podem atuar sinergicamente para o aumento da viscosidade do detergente lava-loiça. A formulação do detergente lava-loiça D2 provou não ser estável ao longo do tempo, em termos de pH e viscosidade, possivelmente devido ao elevado rácio sal/tensioativo presente na sua constituição. Por DLS classificaram-se as micelas como estruturas micelares simples, de tamanho reduzido, cujo tamanho médio para todas as formulações, com exceção da D2, é relativamente estável ao longo do tempo. Os ensaios reológicos mostraram que as formulações em estudo apresentam um comportamento não-newtoniano independente do tempo, sendo estes denominados como pseudoplásticos e também como líquidos viscoelásticos. Hand dishwashing detergents are chemical products, widely used in our daily lives, for cleaning and sanitizing a wide variety of surfaces quickly and effectively. These detergents have physicochemical characteristics such as pH and viscosity that determine their quality and, as such, require monitoring and control during the production process. Some of the hand dishwashing detergents produced by Mistolin show an increasing viscosity over their shelf life, resulting in consumer complaints regarding consistency and consequent difficulty in handling these products. For this reason, arised the need to evaluate the behavior of five different formulations of dishwasher detergents, both concentrated and diluted, regarding viscosity and pH parameters, for different storage temperatures, in order to mimic possible extreme packaging conditions of the products after shipment to the market. During eight weeks, pH and viscosity measurements were made for each one of the formulations under study for different storage temperatures, namely at 4, 25 and 40 ºC. It was found that the pH of the formulations, with the exception of the formulation designated as D2, varies within a stipulated range for each detergent, and that regardless of the storage temperature, the formulations are stable with respect to pH parameter. Regarding viscosity, this parameter increases over time for the storage temperature of 40 ºC, for all but one formulation (formulation D2), indicating that the use of different surfactant mixtures in the formulations, as well as their concentration along with the increase in temperature can act synergistically to increase the viscosity of the dishwashing detergent. The dishwashing detergent formulation D2, proved not to be stable over time in terms of pH and viscosity, possibly due to the high salt-to-surfactant ratio present in its constitution. By DLS the micelles were classified as simple, small-sized micellar structures, whose average size for all formulations except D2 is relatively stable over time. The rheological tests showed that the formulations under study present a non-Newtonian time-independent behavior, being named as pseudoplastic and also as viscoelastic liquids. Mestrado em Engenharia Química

A expansão das fábricas de tintas de tatuagem vem despertando o interesse de ambientalistas devido ao elevado potencial poluidor das águas residuárias produzidas nessas indústrias. Os processos convencionais de tratamento de efluentes não conseguem degradar integralmente todas as substâncias geradas na fabricação das tintas, inserindo no meio ambiente poluentes recalcitrantes, como surfactantes, que são resistentes à degradação biológica. Devido a essa resistência tem surgido a necessidade de métodos mais avançados no tratamento desses poluentes. O objetivo desse estudo foi empregar a cavitação hidrodinâmica associada a substâncias com elevado potencial de oxidação, para degradar poluentes recalcitrantes presentes em águas residuárias da produção de tintas de tatuagens. Experimentalmente a amostra foi submetida ao processo de cavitação hidrodinâmica utilizando placa de orifício como gerador de cavitação. A otimização do aparato de cavitação hidrodinâmica foi baseada na remoção de surfactantes em diferentes valores de pH e pressão de entrada na câmara de cavitação, realizadas em triplicata. Após esta etapa, utilizou-se diferentes cargas de ozônio e volumes de peróxido de hidrogênio para investigar a sinergia entre a cavitação hidrodinâmica e oxidantes na remoção de surfactantes e na redução de carbono orgânico total (COT). As melhores condições experimentais obtidas nos testes de otimização foram conduzidas a um pH de 2,5, pressão de 4,5 bar e carga de ozônio de 3,1 g/h, com eficiência de remoção de surfactantes e COT de 88% e 34 % respectivamente. A adição de peróxido de hidrogênio não produziu melhorias na eficiência de remoção dos compostos. O uso da cavitação hidrodinâmica para o tratamento da amostra do efluente provou ser uma boa opção para auxiliar no tratamento de águas residuárias contendo surfactantes e elevadas concentrações de matéria orgânica. The expansion of tattoo ink factories has attracted the interest of environmentalists due to the high polluting potential of the wastewater produced in these industries. Conventional effluent treatment processes cannot fully degrade all substances generated in the paint manufacturing, introducing recalcitrant pollutants into the environment, such as surfactants, which are resistant to biological degradation. Due to this resistance, the need for more advanced methods to treat these pollutants has arisen. The aim of this study was to use hydrodynamic cavitation associated with the addition of high oxidation potential substances, to degrade an effluent sample generated in a tattoo paint factory. Experimentally, the sample was subjected to the hydrodynamic cavitation process using an orifice plate as a cavitation generator. The optimization of the hydrodynamic cavitation apparatus was based on surfactants removal at differents pHs and inlet pressure into the cavitation chamber, carried out in triplicate. After this step, different ozone charges and hydrogen peroxide volumes were used to investigate the synergy between hydrodynamic cavitation and oxidants in the removal of surfactants and in the reduction of total organic carbon (TOC). The best experimental conditions obtained in the tests were conducted at a pH of 2.5, a pressure of 4.5 bar and an ozone charge of 3.1 g/h, with a removal efficiency of 88% for surfactants and 34% for the removal of TOC. The addition of hydrogen peroxide did not improve the removal efficiency of the compounds. The use of hydrodynamic cavitation to treat the effluent sample proved to be a good option to assist in the treatment of wastewater containing surfactants and high concentrations of organic matter.

Orientador: Rosangela Barros Zanoni Lopes Moreno Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências Resumo: O processo de Surfactante-Polímero (SP) faz parte dos métodos de recuperação melhorada com químicos (CEOR) reconhecidos por atingir maiores fatores de recuperação. Esses métodos tornaram-se atraentes novamente devido à crescente demanda global por energia. Entretanto, ainda caracterizam-se como um desafio para à indústria petrolífera principalmente pela dificuldade para planejar e prever seu comportamento em escala de campo. A compreensão dos fenômenos associados ao processo CEOR é de vital importância. Por estas razões, este trabalho apresenta uma avaliação do processo Surfactante-Polímero (SP) incluindo tomografia computadorizada (CT). O estudo abrange o desenvolvimento do processo em escala de laboratório e descreve as interações químicas e a dinâmica dos fluidos no meio poroso. A pesquisa começa com uma extensa revisão da literatura para determinar as condições gerais de aplicação do processo SP. Além disso, são propostos alguns critérios de seleção para escolher ou avaliar um campo de referência e reproduzir suas propriedades petrofísicas e de fluidos experimentalmente. A primeira etapa experimental deste trabalho consistiu de um estudo detalhado sobre as interações entre os fluidos e os produtos químicos. Esta etapa visou determinar a influência de variáveis tais como temperatura, conteúdo de íons monovalentes e divalentes, e concentração de surfactante no comportamento reológico e viscoelástico das soluções poliméricas. As interações entre as soluções aquosas e a fase oleica foram estudadas por meio de testes de tensão interfacial e comportamento de fases. Além disso, a lei de Bancroft foi empregada como uma ferramenta qualitativa para verificar o tipo de microemulsão obtido. Como resultado, as soluções a serem usadas nos testes de deslocamento foram escolhidas. A segunda parte do estudo abordou atividades previas aos testes de deslocamento. Para isso, amostras de arenito foram selecionadas e caraterizadas de acordo com os critérios de seleção propostos. Em seguida, uma bancada experimental, incluindo um tomógrafo, foi planejada e montada com o objetivo de avaliar a recuperação de óleo por injeção convencional de água e por injeção de surfactante-polímero como método secundário e terciário. O estudo desenvolvido permitiu conhecer o comportamento reológico e viscoelástico da mistura de surfactante-polímero a ser injetada, avaliar o perfil de porosidade e saturação ao longo da amostra de rocha através de imagens de CT e avaliar a eficiência de ambos métodos de recuperação por injeção convencional de água e recuperação melhorada por injeção de surfactante-polímero. A análise comparativa dos resultados de razão agua-óleo (WOR) e corte de agua (Wcut) mostraram a melhoria da mobilidade e a redução da saturação de óleo residual devido à injeção de uma mistura SP sobre a água convencional. Além disso, os resultados comparativos do fator de recuperação de óleo (FR) obtidos através do balanço volumétrico de material e da tomografia computadorizada apresentaram um aumento de FR de 17 e 10 pontos percentuais para esquemas de injeção secundária e terciária, respectivamente. Finalmente, discute-se a eficácia da técnica de imagem e suas vantagens como uma poderosa ferramenta para visualizar imagens 2D e 3D durante os testes de deslocamento. Com isso, pode-se melhorar o entendimento sobre o escoamento de fluidos em meios porosos Abstract: The Surfactant-Polymer (SP) process is a type of Chemical Enhanced Oil Recovery (CEOR) methods known for the possibility of reaching higher oil recovery factors. These methods have become attractive again due to the growing global demand for energy. However, they are still a challenge for the petroleum oil industry mainly because of the difficulty in designing and forecasting the process behavior in the field scale. The understanding of the phenomena associated with a CEOR process is of vital importance. For these reasons, this work presents the assessment of a Surfactant-Polymer (SP) process evaluated by computed tomography (CT). The study covers the development of the process on a laboratory scale and describes the chemical interactions and fluid dynamics in the porous media. The research begins with an extensive literature review that allows the determination of general conditions to apply an SP process. Furthermore, some screening criteria are proposed aims to select a reference field to recreate their petrophysical and fluids properties experimentally. The first experimental stage of this research consists of a detailed study to understand the interactions between the fluids and chemical products (Brine, Oil, Polymer, and Surfactant). This step aims to determine the influence of variables such as temperature, monovalent and divalent ions content, and surfactant concentration on the rheological and viscoelastic behavior of the polymer solutions. The interactions between the aqueous solutions and oil phase were studied through interfacial tension and phase behavior tests. Besides that, the Bancroft Rule¿s was employed as a qualitative tool to verify the type of the microemulsion obtained. As a result, the solutions to be used in core flooding tests were selected. The second part of the study covered the laboratory activities conducted previously to the core flooding tests. For this, sandstone samples were previously characterized and chosen according to the screening criteria. Afterward, an experimental workbench including the CT scan was assembled aiming to evaluate the oil recovery by conventional waterflooding and by SP floodings as secondary and tertiary oil recovery methods. The developed study allowed to know the rheological and viscoelastic behavior of the tailor-made surfactant-polymer blend, evaluate the porosity and saturation profiles along the rock sample through CT images and assess the efficiency of both recovery methods - the conventional waterflooding and the advanced SP. Comparative analysis of the water-oil ratio (WOR) and water cut (Wcut) results elucidated the mobility ratio improvement and oil residual saturation reduction due to the injection of an SP blend over conventional water. Also, comparative results of oil recovery factor (FR) obtained through the volumetric material balance and CT scan show an FR increases of 17 and 10 percentage points for secondary and tertiary injection schemes, respectively. Finally, this work includes a discussion about the effectiveness of the imaging technique and its advantages as a powerful tool to visualize 2D and 3D images during core flooding tests and understanding of fluid flow through a porous media Mestrado Reservatórios e Gestão Mestre em Ciências e Engenharia de Petróleo CAPES 33003017

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Repositório Institucional da UNESP. on 2021-08-27T13:59:37Z (GMT) Submitted by Bruna Pastrello (bruna.pastrello@unesp.br) on 2021-08-28T16:00:00Z No. of bitstreams: 1 tese_brunapastrello_final_biblioteca.pdf: 6571710 bytes, checksum: f3f0db79f576520f3cafb99258213d35 (MD5) Approved for entry into archive by Celia Silva Cruz Morales (celia.morales@unesp.br) on 2021-08-30T12:19:41Z (GMT) No. of bitstreams: 1 patrello_b_dr_bauru.pdf: 6571710 bytes, checksum: f3f0db79f576520f3cafb99258213d35 (MD5) Made available in DSpace on 2021-08-30T12:19:41Z (GMT). No. of bitstreams: 1 patrello_b_dr_bauru.pdf: 6571710 bytes, checksum: f3f0db79f576520f3cafb99258213d35 (MD5) Previous issue date: 2021-07-30 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) As quinolinas possuem um núcleo heterocíclico que está presente em diversas moléculas com interesse biológico e tecnológico. Quinolinas polissubstituídas podem apresentar sistema eletrônico conjugado (D-π-A), o que as torna moléculas fluorescentes e susceptíveis ao meio. Neste trabalho foram sintetizadas nitroquinolinas através de reações multicomponentes e reduzidas à aminoquinolinas fluorescentes. Estes compostos foram estudados tendo como foco suas propriedades solvatocrômicas e interação com albumina, lisozima e micelas. Estudos solvatocrômicos utilizando os modelos Lippert, Bilot-kawski, Kawski e McRae, foram realizados utilizando dezesseis solventes. O melhor resultado foi obtido utilizando a aminoquinolina com substituinte -N(CH3)2 (AQ4), onde um coeficiente de correlação de 0,8746 foi obtido para a correlação entre a somatória dos máximos de absorbância e fluorescência das aminoquinolinas e a função de polaridade de solvente φ(ε,n). A partir dessa correlação foi possível estimar a constante dielétrica no interior da proteína BSA. A interação das aminoquinolinas com a proteína BSA provocou um significativo aumento no rendimento quântico das mesmas (22,5%) quando comparado ao meio aquoso (1,04%). A interação da aminoquinolina AQ4 com a proteína BSA mostrou uma constante de associação entre 2,5.105 e 4,5.105 M-1 dependendo do método de utilizado, o que a caracteriza como um ligante semelhante a fármacos que se ligam à BSA. As alterações de fluorescência da AQ4 mostraram-se sensíveis a desnaturação, bem como a formação de agregados amiloides nas proteínas BSA e lisozima, o que possibilitou sua aplicação para monitorar estas alterações nas proteínas estudadas. Estudos de aplicação das aminoquinolinas para determinação de formação de micelas em meio aquoso mostraram que as mesmas podem ser utilizadas para a determinação da concentração micelar crítica (CMC) de diferentes surfactantes. Os valores de CMC foram similares aos apresentados na literatura utilizando diferentes metodologias analíticas. Além disso, as aminoquinolinas foram capazes de detectar a carga elétrica das micelas, onde um deslocamento batocrômico intenso foi exclusivo de micelas negativas. Em conclusão, as aminoquinolinas se mostraram como sondas fluorescentes de significativa aplicabilidade para o estudo proteínas e sistemas micelares. Quinolines have a heterocyclic center that can be seen in several molecules of biological and technological interest. Quinolines containing several substitutions may have a conjugated electronic system (D-π-A), which makes them fluorescent and susceptible to the medium. In this work, nitroquinolines were synthesized athwart multicomponent reactions and then reduced to fluorescent aminoquinolines. These synthesized compounds were studied with focus on their solvatochromic properties and interaction with albumin, lysozyme and micelles. Solvatochromic studies were made using the models of Lippert, Bilot-kawski, Kawski and McRae, sing sixteen solvents. The best result was obtained using aminoquinoline with substituent -N(CH3)2 (AQ4), where a correlation coefficient of 0.8746 was obtained for the linear correlation between the sum of absorbances and fluorescence maximums values of aminoquinolines and the dielectric constant for each solvent φ (ε, n) used. On this correlation, it was possible to estimate the dielectric constant inside the BSA protein. Besides that, the interaction of aminoquinolines with the BSA protein caused a significant increase in AQ4’s quantum yield (22.5%) when compared to the aqueous medium (1.04%). Other result found in this study is that the interaction of the aminoquinoline AQ4 with the BSA protein exhibited a constant association between 2.5.105 and 4.5.105 M-1 depending on the method used, which is characteristic and similar values of ligands that are known to have a good bind with BSA. The fluorescence changes in AQ4 were sensitive to denaturation, as well as the formation of amyloid aggregates in BSA and lysozyme proteins, showing that AQ4 can be applied to monitor changes in the studied proteins. The studies of aminoquinolines in order to determine the formation of micelles in aqueous media have shown that these synthesized molecules can be used to determine the critical micellar concentration (CMC) of different surfactants. The CMC values found with this new method were similar to those presented in the literature using different analytical methodologies. In addition, aminoquinolines were useful to detect the electrical charge of the micelles, once an intense bathochromic displacement was exclusive to negative micelles. In conclusion, aminoquinolines synthesized here can be use as fluorescent probes for the study of proteins and micellar systems. CAPES PROEX Posmat

Orientador: Edvaldo Sabadini Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química Resumo: O colapso de bolhas ocorre devido à sua elevada energia de superfície. Quando surge um ponto de ruptura no filme líquido, sua retração se inicia e, na faixa de milissegundos, converte a energia potencial de superfície em energia cinética. Apesar da tensão superficial que o filme está submetido, o processo de colapso ocorre a uma velocidade constante. Isso ocorre, pois à medida que o filme retrai, há um aumento de líquido nas bordas da cavidade em expansão. Assim, este aumento de massa nas bordas é responsável por certa desaceleração, fazendo com que a velocidade do colapso da bolha seja constante. Este comportamento geral é o esperado para bolhas formadas com soluções de surfactantes. Neste trabalho foi mostrado pela primeira vez que bolhas formadas por soluções contendo o surfactante catiônico brometo de cetiltrimetilamônio (CTAB) e determinados ânions aromáticos, como o salicilato de sódio, produzem efeitos elásticos que não podem ser descritos pela evolução do colapso da bolha descrita anteriormente. Isto se deve ao fato de que na combinação do CTAB com os ânions aromáticos, ocorre a formação de micelas gigantes. Neste caso, as moléculas aniônicas se inserem entre as cabeças das moléculas dos surfactantes mudando a curvatura do agregado formado. A presença de micelas gigantes foi caracterizada na superfície solução/ar através de espectroscopia de soma de frequência. Assim, quando as bolhas são formadas, as cadeias das micelas gigantes presentes no filme líquido das mesmas se esticam no campo de cisalhamento, armazenando energia elástica. Quando o filme da bolha é rompido, além da energia superficial, a energia elástica referente as cadeias micelares esticadas contribui para aumentar a velocidade de retração da bolha. Em alguns casos a velocidade de retração chega a ser em torno de vinte vezes mais rápida em relação as bolhas sem micelas gigantes. Para execução dos experimentos foi usada uma câmera digital com captura de imagens de 6000 fotos por segundo, permitindo obter medições quantitativas sobre alterações na velocidade de retração do filme, bem como alterações morfológicas produzidas pelas micelas gigantes Abstract: The bubble collapse occurs due to its high surface energy. When there is a collapsing point in the liquid film, its retraction begins and within a milliseconds it converts the surface potential energy into kinetic energy. Despite of the surface tension exerted on film, the collapse process occurs at constant speed. This occurs because, as the film retracts, there is an increase in liquid at the edges of the expanding cavity. Thus, this mass increase at the edges is responsible for some deceleration, resulting in a constant speed during the bubble collapse. This general behavior is expected for bubbles formed through surfactant solutions. This work was the first to show that bubbles formed by solutions containing the cationic surfactant cetyltrimethylammonium bromide (CTAB) and certain aromatic anions such as sodium salicylate, produce elastic effects that cannot be described by the afore mentioned soap bubble collapse evolution. This is due to the fact that the combination of CTAB with aromatic anions causes the formation of giant micelles. In that case, the anionic molecules are inserted between the heads of the surfactant molecules, changing the curvature of formed aggregate. The presence of giant micelles was characterized on the solution/air surface through sum frequency spectroscopy. When the bubbles are formed, the giant micelles chains present in the liquid film stretch in the shear field, storing elastic energy. When the bubble film is ruptured, in addition to the surface energy, some elastic energy stored in the stretched micellar chains adds to the bubble speed retraction. In some cases the retraction speed is up to around twenty times faster than in the bubbles without giant micelles. A digital camera was used in the experiments to capture 6000 frames per second, allowing the obtainment of quantitative measurements in the changes in the retraction speed of the film, as well as morphological changes produced by the giant micelles Doutorado Físico-Química Doutor em Ciências PETROBRAS

espanolSe aplica la transformada de Fourier en el analisis del desgaste superficial de la leva anular de la bomba de alta presion DENSO HP3 al utilizar la mezcla combustible ecologica diesel - surfactante - agua al 20%, que es una emulsion de dos sustancias tenso activas no ionicas, durante 200 horas de funcionamiento a 3000 rpm, con inspecciones cada 50 horas. El combustible ecologico reduce las emisiones, aumenta la eficiencia termica, torque y potencia del motor de combustion interna, como demuestra el analisis experimental, la balanza de precision detecta la reduccion de 0,121 gramos en la masa de la leva, el rugosimetro digital determina la rugosidad Ra en la cara frontal de la leva estableciendo el 22,33% de desgaste en relacion con el perfil ideal de experimentacion, para la cara posterior 40,35% de desgaste, con el modulo didactico generado en Matlab para el procesamiento digital de imagenes y la transformada de Fourier se compara el perfil ideal y el perfil de rugosidad de la leva anular en terminos de la frecuencia de las imagenes, aplicando herramientas estadisticas como el promedio del maximo y minimo de intensidad. El uso de la mezcla combustible diesel surfactantes agua al 20%, en la bomba de alta presion HP3 genera desgastes prematuros en las superficies de la leva. Con el proposito de generar un aporte investigativo se incluyen la metodologia y tecnica de pruebas en el dinamometro para estimar las caracteristicas de desempeno fundamental del motor de combustion interna diesel con este tipo de biocombustible. EnglishThe Fourier Transform is applied in the analysis of the surface wear of the annular cam of the high-pressure pump DENSO HP3 using the ecological fuel mixture diesel - surfactant - water at 20%, which is an emulsion of two tense-active non-ionic substances during 200functioning hours at 3000 rpm with inspections performed each 50 hours. The ecological fuel reduces the emissions, enhance the thermal efficiency, torque, and power of the internal combustion motor; as it is shown in the experimental analysis, the precision balance it is detected the reduction of 0.121 grams of mass in the cam, with the digital roughness meter it is determined the roughness Ra on the frontal face of the cam, establishing a 22.23% of wear in relation with the ideal profile of experimentation, for the rear face 40.35% of wear, with the didactic module generated on Matlab for the digital image processing and the Fourier Transform compares the ideal profile and the roughness profile of the annular cam in terms of image frequency, using statistics tools such as the maximum average and the minimum o intensity. The use of the mixture of the diesel-surfactant-water fuel at 20% on the high-pressure pump HP3 generates premature wear on the cam surfaces. With the purpose of generating an investigating contribution, it is included the methodology and the technic of tests and measurements on the dynamometer for estimating the fundamental performance characteristics of the diesel internal combustion motor with this type of fuel.

Microflotation experiments and zeta potential measurements of fluorapatite, wavellite, and turquoise with the use of alkyl amines and amylopectin were conducted. The highest floatability values were achieved in the presence of dodecylamine, exceeding the floatabilities with octylamine between 30% and 90%. Above their respective isoelectric points, the phosphates reached approximately 100% of floatability with dodecylamine. The strong dependence of surfactant adsorption on hydrocarbon chain length was also evidenced by zeta potential results. In the presence of 1 × 10−3 M dodecylamine solution, the surface charge of the phosphates changes from negative to positive until approximately pH 12, while the octylamine was not able to reverse the surface charges. The fluorapatite and wavellite floatabilities were not significantly affected by the amylopectin; however, in the presence of this depressant, the turquoise floatability, with octylamine as collector, decreases abruptly from 93% to 30%. The greater differences observed between turquoise and the other phosphates can be ascribed to their extremely complex structures, chemical composition and its dissolution in aqueous media. Keywords: Fluorapatite, Wavellite, Turquoise, Floatability, Alkyl amine, Zeta potential

Surfactant-mediated coacervates are termed as the new age microreactors for their ability to spontaneously sequester the molecules with varied polarities and functionalities. Efforts to emulate this applicability of coacervates through synthetic control of surfactant structures are finding success; however, there is little understanding of how to translate these changes into tailor-made properties. Herein, we designed 3-methyl-1-(octyloxycarbonylmethyl)imidazolium bromide (C8EMeImBr), an ester-functionalized ionic liquid-based surfactant, which shows better surface active properties than the nonfunctionalized and conventional cationic surfactant and forms complex coacervates over the broad range of concentration with sodium salicylate (NaSal). Mono- and divalent cations as well as ionic strength, viscosity, and time-dependent stability of the coacervates had also been addressed in order to study whether these coacervates could work as microreactors to encapsulate various molecules. The anionic charged complex coacervates with sponge morphology and honey comb-like interior show good efficiency to sequester cationic dyes from water because of electrostatic and hydrophobic interactions and good encapsulation efficiency for curcumin owing to their high surface area. Results suggest that ionic liquid-based coacervates studied here could be exploited as a novel low-cost, effective, and environmentally benign alternative to sequester dyes from the contaminated water and their recovery.

Orientadores: Carlos Raimundo Ferreira Grosso, Rosemary Aparecida de Carvalho Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Doutorado Consumo e Controle de Qualidade Doutor em Alimentos e Nutrição

Orientador: Ulf Schuchardt Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química Resumo: Derivados de óleos vegetais foram preparados utilizando-se catalisadores homogêneos e heterogêneos. Em quatro diferentes estudos foram produzidos epóxidos, hidroxi-éteres vicinais, antioxidantes e surfactantes. Os epóxidos graxos foram preparados a partir de oleato de metila, bem como óleo de soja e seus ésteres metílicos através de três métodos: (i) químio-enzimático; (ii) convencional (geração in situ de um perácido de cadeia curta) e (iii) catalítico, com peróxido de hidrogênio na presença de aluminas. Em todos os sistemas foram obtidas conversões > 90 % e seletividades > 95 %. Os rendimentos em epóxidos do sistema envolvendo as aluminas foram semelhantes aos obtidos com perácidos de cadeia curta. A alumina mais ativa foi utilizada em quatro epoxidações sem perdas significativas na atividade. Os experimentos de abertura de anéis oxirânicos presentes em ésteres graxos epoxidados, para a obtenção de hidroxi-éteres vicinais, foram realizados com metanol, isopropanol e etilenoglicol. Nos experimentos com isopropanol, o catalisador mais ativo - argila montmorilonita modificada com o ácido dodecatungstofosfórico - permitiu conversão > 98 % e seletividade de 95 % para os produtos de interesse. Nas reações com etilenoglicol foram obtidos produtos com elevadas massas molares, resultantes da formação de dímeros, trímeros e de outras espécies oligoméricas. Em outra parte do estudo foram sintetizados antioxidantes lipofílicos a partir de ácido ascórbico e compostos graxos, como estearato de vinila, oleato de metila e ácido oléico. Nas reações catalisadas por preparados enzimáticos, o substrato vinílico mostrou-se o mais eficiente, levando a rendimentos próximos de 75 % para o ascorbato nas condições otimizadas. O procedimento adotado mostrou-se inadequado para a obtenção de ascorbatos insaturados (rendimentos abaixo de 25 %). Na parte final, é descrita a preparação de uma betaína a partir de óleo de babaçu, com o objetivo de avaliar a utilização desse insumo em substituição aos óleos de coco e de palmiste, normalmente utilizados como matéria-prima na produção de betaínas. A metodologia empregada mostrou-se adequada e o produto foi obtido como uma solução aquosa com concentração próxima de 30 % (m/m). Abstract: Vegetable oil derivatives were prepared using homogeneous and heterogeneous catalysts. In four different studies, epoxides, vicinal hydroxyl-ethers, antioxidants and surfactants were obtained. The fatty epoxides were prepared from methyl oleate, as well as soybean oil and its methyl esters mixture, using three methods: (i) chemo-enzymatic; (ii) conventional (short chain peracid in situ generation) and (iii) catalytic, with hydrogen peroxide in presence of aluminas. Conversion > 90 % and selectivity > 95 % were obtained for all the systems. For the system with alumina, epoxide yields were next to the obtained with short chain peracids. The most active alumina could be used in four epoxidations without significant reactivity loss. The ring opening reactions using epoxidized fatty esters were carried out with methanol, isopropanol and ethylene glycol. With isopropanol, the more active catalyst - K10 montmorillonite clay modified with dodecatungstophosphoric acid - allowed a conversion > 98 % and selectivity of 97 %. High molar mass products were obtained in the reactions with ethylene glycol; such products result from the formation of dimers and trimers, among other oligomeric species. In another part of the work, lipophilic antioxidants were synthesized from ascorbic acid and fatty compounds, such as vinyl stearate, methyl oleate and oleic acid, using enzymatic catalysts. The vinylic substrate was the more efficient, allowing 75 % of ascorbate yield. The employed procedures were unsuitable for the production of unsatured ascorbates (yields > 25 %). The final part describes the preparation of a betaine from babaçu oil. The aim was to evaluate this oil as a substitute for coconut and palmiste oils, usually used for betaine production. The methodology was suitable and the product was obtained as an aqueous solution (30 % m/m). Doutorado Química Inorgânica Doutor em Ciências

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) This work assessed the hepatic effect of carbon nanotubes (CNT) [10 mg.L-1] (NT group; n=9) associated with Pluronictm F-127 (0,1%), as well as its isolated effect (ST group; n=9), by the analysis of hepatic biomarkers in bullfrog tadpoles, Lithobates catesbeianus (SHAW, 1802), after 96h of exposure. The melanomacrophage cells area (A.MMC), sinusoidal area (A.SINUS), parenchymal area (A.HP), and the number of hepatocytes (C.HP) were assessed using hematoxylin-eosin (HE). The percentage of area occupied by lipids (A.SB) were assessed using a histochemistry technique (Sudan Black). We observed a reduction of the A.SINUS (P

Orientador: Edvaldo Sabadini Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química Resumo: Uma importante propriedade dos surfactantes é a tendência de formação de agregados em solução, como micelas esféricas, micelas cilíndricas, lamelas entre outros. Dentre os diferentes tipos de agregados que podem ser formados, há o caso especial de formação de micelas gigantes, que apresentam uma rica e complexa reologia, fazendo delas algo tão interessante para aplicações práticas. A reologia de micelas gigantes formadas pela combinação do surfactante catiônico cloreto de cetilpiridínio (CPyC) e salicilato de sódio foi detalhadamente explicada na década de 1980. A transição de micelas esféricas para alongadas (e a correspondente reologia) é um processo altamente sensível às estruturas moleculares das espécies envolvidas ¿ surfactantes e cossolutos. Neste trabalho, buscou-se contribuir com o entendimento deste processo, estudando a influência das estruturas químicas de cossolutos aromáticos (benzoato de sódio, salicilato de sódio, benzeno sulfonato de sódio e 2-hidróxi benzeno sulfonato de sódio) combinados com surfactantes catiônicos (CTAB - brometo de cetiltrimetil amônio e CPyC - cloreto de cetilpiridínio), em diferentes proporções, na formação e comportamento reológico de micelas gigantes. Para os cossolutos avaliados, verificou-se que parâmetros como a polarizabilidade, a planaridade molecular e a afinidade do cossoluto pela fase aquosa podem influenciar a formação de micelas gigantes, no entanto, não é possível explicar o comportamento reológico baseando-se em uma única característica do cossoluto aromático. Verificou-se também que os sistemas formados com CTAB apresentaram viscosidades no repouso sempre maiores do que os análogos formados com CPyC Abstract: An important property of surfactants is their tendency to form aggregates in solution, such as spherical micelles, rods, lamellae and others. Among the different types of aggregates that can be formed, there is the special case of formation of worm-like micelles, which present a rich and complex rheology, making them interesting for practical applications. The rheology of worm-like micelles formed by the combination of the cationic surfactant cethylpyridium chloride (CPyC) and sodium salicilate was explained in details in the 1980s. The transition from spherical to elongated micelles (and the corresponding rheology) is a process highly sensitive to the molecular structures of the involved species - surfactants and co-solutes. In this work, we sought to contribute to the understanding of this process by studying the influence of the chemical structures of aromatic co-solutes (sodium benzoate, sodium salicylate, sodium benzene sulfonate and sodium 2-hydroxy benzene sulfonate) combined with cationic surfactants (CTAB - cetyltrimethylammonium bromide and CPyC - cetylpyridinium chloride), in different proportions, to the formation and rheological behavior of worm-like micelles. For the evaluated co-solutes, we verified that the polarizability, molecular planarity and affinity of the co-solutes for the aqueous phase can influence the formation of worm-like micelles, however, it was not possible to explain the rheological behavior based on a single characteristic of the aromatic co-solute. It has also been found that systems formed with CTAB always displayed larger zero shear viscosities than the analogs formed with CPyC Mestrado Físico-Química Mestre em Química

Orientador: Cláudio Francisco Tormena Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química Resumo: DOSY ("Espectroscopia de Difusão Ordenada") baseia-se na capacidade de separação de sinais de compostos diferentes de acordo com o seu coeficiente de difusão, e por isto, dificuldades surgem quando sinais se sobrepõem ou quando os compostos possuem tamanhos muito semelhantes. O que é uma situação muito comum em análises de soluções de isômeros ou quando espécies quimicamente semelhantes estão presentes. A sobreposição de sinais pode ser evitada pelo uso de um núcleo diferente do tradicional 1H, tal como o 19F, cujos espectros possuem uma gama espectral grande, o que tipicamente leva a sinais bem resolvidos. Quanto aos componentes de tamanho semelhante, o progresso em MAD ("DOSY Auxiliado por Matriz") solucionou este problema e reforçou o DOSY como uma ferramenta poderosa. MAD dá ao analista o poder de manipular o comportamento de difusão dos compostos, por interação com uma matriz, geralmente um agente surfactante ou um agente de complexação, que interage diferente com cada componente da mistura. Aqui se demonstra a utilização de uma sequência de pulsos de 19F DOSY para vários benzenos fluorados. Para os compostos com constantes de acoplamento nJFF, a "modulação devido ao J" pode ser suprimida usando a sequência Oneshot45. Também se avalia a eficiência de micelas de SDS e AOT como agentes de separação para soluções dos isômeros de fluorfenóis e fluoranilinas. O sitio de interação, entre solutos e surfactantes, foram investigados utilizando experimentos medindo o efeito Overhauser nuclear. 19F MAD fornece uma ferramenta poderosa para a análise de misturas, com o potencial de ser muito útil para o estudo de medicamentos, em particular, no estudo de degradação de fármacos Abstract: DOSY (Diffusion-Ordered Spectroscopy) analysis is based on the ability to separate signals from different compounds depending on their diffusion coefficient, and can therefore struggle when NMR signals overlap or when the compounds are of very similar size. This is naturally a common situation in drug analysis, where isomers and other chemically similar species are present. Signal overlap can be avoided by using a nucleus such as 19F instead of the traditional 1H, because 19F NMR spectra are typically very sparse and have a much larger spectral range, leading to well-resolved signals. As for the similar size components, developments in "Matrix-Assisted DOSY" (MAD) have alleviated this problem and further strengthened DOSY as a powerful tool. MAD gives the analyst the power to manipulate diffusion behaviour by differential interaction with a matrix, commonly a surfactant or a complexation agent, binding differently with the each component of the mixture. Here, we demonstrate the use of a modified 19F DOSY experiment for various fluorinated benzenes. For compounds with significant nJFF coupling constants, as is common, the undesirable "J-modulation" can be efficiently suppressed using the Oneshot45 pulse sequence. We have also evaluate the efficiency of SDS (normal) and AOT (reverse) micelles as separation agents for mixtures containing positional isomers of fluorophenols and fluoroanilines using 19F MAD. The interaction sites between solutes and surfactants were investigated using different Nuclear Overhauser Effect experiments. 19F MAD provides a powerful tool for mixture analysis by NMR with the potential to be very useful for the study of pharmaceutical formulations, in particular in the study of drug degradation Mestrado Química Orgânica Mestre em Química CNPQ FAEPEX

Submitted by Felipe De La Rua Müzel (felipe.muzel@unesp.br) on 2021-03-23T00:05:55Z No. of bitstreams: 1 Dissertação Felipe De La Rua Müzel.pdf: 1886141 bytes, checksum: 5f59ddea7c6d6e9e9a2d7154461126d2 (MD5) Approved for entry into archive by Ana Carolina Gonçalves Bet null (abet@iq.unesp.br) on 2021-03-23T12:19:05Z (GMT) No. of bitstreams: 1 müzel_fr_me_araiq_int.pdf: 1886141 bytes, checksum: 5f59ddea7c6d6e9e9a2d7154461126d2 (MD5) Made available in DSpace on 2021-03-23T12:19:05Z (GMT). No. of bitstreams: 1 müzel_fr_me_araiq_int.pdf: 1886141 bytes, checksum: 5f59ddea7c6d6e9e9a2d7154461126d2 (MD5) Previous issue date: 2021-03-09 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Surfactantes aniônicos são amplamente utilizados na indústria de cosméticos brasileira e mundial. O mercado de cosméticos está sempre em inovação pela demanda da sociedade por novos produtos. Pela grande produção existente devem existir métodos de controle da quantidade desse analito nos produtos comercializados. Há descrito na literatura diversas técnicas de quantificação, que apresentam alguns pontos negativos, como técnicas cromatográficas e espectrométricas, que são grandes consumidoras de produtos orgânicos, principalmente de solventes como clorofórmio e tolueno, que são nocivos ao operador e ao meio ambiente. Há também a utilização de métodos eletroanaliticos que possuem grande interferências de proteínas em determinações. Nesse sentido, no presente trabalho foi desenvolvida uma nova metodologia para determinação de surfactantes aniônicos em amostras de matérias-primas e de produtos cosméticos comerciais de shower gel e sabonete líquido, que não utilizasse solvente orgânico durante o procedimento, sem riscos ao operador, e seguindo a filosofia da Química Verde com redução de geração de resíduos, com detecção por espectrofotometria UV-Vis e por imagem digital. A curva analítica apresentada para a espectrofotometria foi A665nm = 0,006161Csds - 0,943897 com R² = 0,992 e LD = 6,05 x 10-6 mol L-1 (1,74 mg L-1) e LQ = 2,02 x 10-5 mol L-1 (5,83 mg L-1), e a curva para a imagem digital foi Ir = 0,002537Csds + 0,004354 com R² = 0,990 e LD = 9,40 x 10-6 mol L-1 (2,71 mg L-1) e LQ = 3,21 x 10-5 mol L-1 (9,28 mg L-1), as curvas apresentaram menos de 10 % de desvio padrão relativo em todos os pontos para os estudos intra e inter dias, demonstrando repetibilidade, e possuem a faixa linear de trabalho de 3,46 x 10-5 mol L-1 (10 mg L-1) a 3,46 x 10-4 mol L-1 (100 mg L-1) . Os testes para avaliação de interferência da matriz por meio da adição padrão apresentaram recuperação entre 103,02 % e 96,32 %, concluindo-se que a matriz não interfere de forma significativa na determinação dos analitos. A metodologia desenvolvida foi comparada com o método oficial descrito na literatura por meio de testes estatísticos, demonstrando que não há diferença significativa entre os valores encontrados pelas duas metodologias. Anionic surfactants are widely used in the Brazilian and worldwide cosmetics industry. The cosmetic market is always looking for innovation and the society demands new products. Because of the great production there must be methods for controlling this analyte in the marketed products. The methodologies used to determinate this analyte show negatives points, i.e., chromatographic, and spectrometric techniques that consume large amounts of organics products, mainly solvents like chloroform and toluene harmful to the operator and to the environment. The use of electroanalytical processes is common too, but there is the interference of proteins in the determinations. In this context, the following study aims to develop a new quantification methodology of anionic surfactant without the consume of organic solvents during the process, without risks to the operator, that follows the philosophy of green chemistry without waste, with detection by spectrophotometry and digital image for raw material sample, commercial shower gel and liquid soap. The obtained analytical curve for spectrophotometry was A665nm = 0,006161Csds - 0,943897 and R² = 0,992 with LD = 1,74 mg L-1 and LQ = 5,83 mg mg L-1 and the curve for the digital image was Ir = 0,002537Csds + 0,004354 and R² = 0,990 with LD = 2,71 mg L-1 and LQ = 9,28 mg L-1, both analytical curves showed less than 10 % of standard deviation at all points, having good repeatability and the method have a linear working range of 3,46 x 10-5 mol L-1 (10 mg L-1) to 3,46 x 10-4 mol L-1 (100 mg L-1). The tests for the interferents evaluation of the matrix by the standard addiction showed recuperation between 103,02 % and 96,32 %, concluding that the matrix did not interfered in the determination of the analyte. The methodology was compared with the official method described in the literature with statistically tests, demonstrating not statistically difference between the values obtained by the two methodologies. CAPES: 88887.341553/2019-00

La eliminación de contaminantes emergentes como los tensioactivos en fuentes acuosas es uno de los principales desafíos que enfrenta el tratamiento de aguas residuales. Los tensioactivos son contaminantes difíciles de tratar debido a su gran variedad y uso. Existe una amplia variedad de tensioactivos dependiendo de su aplicación. Estos han generado un impacto negativo en el medio ambiente debido al inadecuado tratamiento de sus residuos, donde la mayoría de estos se depositan en fuentes de agua, como ríos y mares afectando a la vida silvestre y al ecosistema debido a su marcada actividad biológica, afectan al ecosistema. Los tensioactivos son moléculas anfifílicas que tienen una parte hidrofílica (cabeza) y una parte hidrofóbica (cola) y son compuestos que modifican la tensión superficial en la interfase. Cuando su concentración es menor que la concentración micelar crítica (CMC) están en solución en forma de monómeros, mientras que cuando su concentración es superior a la CMC forman micelas. Por este motivo, se utilizan como detergentes, emulsionantes, desinfectantes y humectantes. Aunque existe una amplia gama de tecnologías para la remoción, destrucción, transformación o aprovechamiento de residuos líquidos, los sistemas de tratamiento convencionales empleados actualmente son inadecuados para remover completamente los surfactantes del agua, por lo que se requieren tratamientos más efectivos con el fin de reducir el impacto ambiental de los efluentes y cumplir con unas normativas legislativas que son cada vez más estrictas. Uno de estos procesos alternativos es la adsorción en carbones activados, debido a sus bajos costos y especificidad. El carbón activado es un adsorbente que se puede obtener a partir de materiales de desecho, como desechos de llantas o desechos lignocelulósicos, que tiene la capacidad de adsorber diversas sustancias, junto con una gran facilidad y rapidez de eliminación del medio tratado y la capacidad de ser regenerado para su reutilización, lo que permite un tratamiento eficiente y económico en diversas aplicaciones. Por tal razón este proyecto de investigación se centra en el desarrollo de materiales porosos que permitan retirar de manera eficiente surfactantes presentes en solución acuosa. Para ello se prepararon carbones activados desde dos residuos diferentes como son: desechos de llantas y cáscara de coco. Se realizo el tratamiento de la materia prima, empleando dos tamaños de partícula 0,3mm y 5,0mm y se procedió a la preparación de los carbones activados empleando activación física con dióxido de carbono y activación química con hidróxido de potasio y ácido fosfórico al 10, 20, 30 y 40 %p.p-1, a una velocidad de calentamiento de 2°C.min-1, con un flujo de 100mL.min-1 y empleando dos temperaturas finales de carbonización 700 y 900°C. Se obtuvo un total de 65 sólidos de carbón, a los cuales se realizó caracterización estructural, textural y química. En base a esa caracterización y realizando un diseño experimental por Minitab se eligieron 32 muestras con las cuales se realizaron estudios de adsorción y estudios cinéticos con tres diferentes surfactantes: aniónico, catiónico y no-iónico.

Orientador: Edvaldo Sabadini Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química Resumo: Surfactantes são moléculas anfifílicas que têm capacidade de se ordenar na interface de um líquido, diminuindo sua tensão superficial. Além disso, elas possuem a característica de auto agregação, gerando diversas morfologias de acordo com a proporção entre a área de sua parte polar e o volume de sua parte apolar. Uma dessas morfologias são as micelas gigantes, que são agregados de formato cilíndrico alongados. Quando formadas por surfactantes catiônicos, como o brometo de hexadeciltrimetilamônio (CTAB), empregado neste trabalho, necessitam ser utilizadas alta concentração de sal inorgânico ou por meio de uma molécula aromática com grupamentos polares em sua estrutura, como por exemplo o 2,3-dihidroxinaftaleno (DHN), que foi o alvo deste estudo. Em determinadas concentrações, as micelas gigantes formadas por CTAB e DHN podem alterar a viscosidade do meio em que se encontram, gerando géis. Apesar deste potencial, o DHN sofre reação química em meio aquoso, o que dificulta sua utilização. Porém, a formação de um complexo estável e de estequiometria variável em função do pH entre o DHN e o ferro(III) (Fe(III)) inibe a reação que o aromático sofre. Quando em presença de CTAB em determinados pH, o complexo formado peptiza-se, formando nanopartículas. Quando em regimes de concentração superiores, as micelas gigantes formadas por CTAB e DHN sofrem diversos efeitos quando na presença de Fe(III), tornando o sistema com estes três componentes extremamente complexo e interessante Abstract: Surfactants are amphiphilic molecules that have ability to order in liquid interfaces, lowering the surface tension. Besides, they have the characteristic of self-aggregation, creating different morphologies according to its polar and apolar regions. One of these morphologies are the giant micelles, cylindric and elongated aggregates. When made by cationic surfactants, like hexadecyltrimethylammonium bromide (CTAB), used on this work, it is required a high concentration of inorganic salt or by means of an aromatic molecule, 2,3-dihydroxynaphtalene (DHN) for example, that was the target of this study. In determined concentrations, giant micelles made by CTAB and DHN can alter the viscosity of the media they are into, forming gels. Despite that potential, DHN suffers from a chemical reaction when in water, making its utilization difficult. However, the formation of a stable and pH dependent stoichiometry varying complex between DHN and Iron(III) (Fe(III)) inhibits the aromatic molecule reaction. When in CTAB presence, depending on the pH, the produced complex peptizes, generating nanoparticles. At higher concentration regimes, giant micelles composed by CTAB and DHN suffer various effect according to Fe(III) concentration, making the system with these three components extremely complex and interesting Mestrado Físico-Química Mestre em Química CAPES

International audience; The effect of the presence of surfactant micelles and of the mode of incorporation (pre-homogenization or post-homogenization) on the antioxidant efficiency of a homologous series of n-alkyl gallates phenolipids (G0, G3, G8, G12 or G16) was investigated in oil-in-water nanoemulsions. In both absence and presence of surfactant micelles, G12 and G16 were the best antioxidants. The effect of the mode of incorporation was modulated by the presence of surfactant micelles. In absence of surfactant micelles, G8 and G16 had higher efficiency when incorporated pre-homogenization, suggesting that the mode of incorporation promoted a distinct initial distribution of these compounds. In contrast, in presence of surfactant micelles, the antioxidants could be incorporated in any phases without efficiency loss. These results demonstrate the important role of surfactant micelles in modulating the antioxidant efficiency and could be used by the food industry to optimize emulsion formulations.

From raw materials from renewable sources derived from Brazilian biomass, cardanol and glycerol, pegylated amphiphilic compounds (compounds 3 and 4, respectively) and a gemini surfactant (5) were synthesized, which were characterized by nuclear magnetic resonance spectrometry (1H and 13C NMR), Infrared (IR) spectroscopy and Mass spectrometry. Solutions of varying concentrations from 3,35 x1 0-3 to 4,25 x 10-11 mol L-1 were prepared and measurements of dynamic light scattering (DLS) werw performed, Fluorescence, Infrared and Polydispersity (PDI) were performed. Then it was possible to obtain the critical micellar concentration (CMC) of the compounds. Therefore, the critical micellar concentration of surfactant 4, in the value of 8 ± 5 ˣ 10-10 mol L-1, was determined by the dynamic light scattering technique and by pyrene fluorescence. It was not possible to obtain the respective critical micellar concentrations of surfactants 3 and 5 by the same techniques. Through the dynamic light scattering technique, the hydrodynamic diameter (Dh) of the micelles was determined, as well as the respective polydispersity of each surfactant, in different concentrations. Surfactant 3 supplied micelles in water with average micellar sizes around 320 nm, at the various dilutions and temperatures studied. At a temperature of 45 °C and at a concentration of 2.9 ˣ 10-5 mol L-1, however, it presented sizes of 73.35 nm, with moderate polydispersity. The surfactant gemini 5 supplied micelles in water in sizes suitable for nanoreactors in the range of 51.45 to 106.0 nm, at a concentration of 1.86 ˣ 10-5 mol L-1 and at temperatures of 10, 15, 25 and 35 °C. Sizes of 94.6 and 80.6 nm were observed for the molar concentration of 1.86 ˣ 10-8 mol L-1 at temperatures of 10 and 15 °C, respectively. In the other dilutions and temperatures, the sizes of the micelles were above the range of 115 to 645 nm. Surfactant 4 provided micelles with ideal sizes for micellar catalysis. Particularly, at room temperature (25 °C) micelles in the range of 38.97 - 86.92 nm are formed in different concentrations. At a concentration of 3.35 ˣ 10-3 mol L-1, the hydrodynamic radius was 86.92 nm and the polydispersity

Atrazine’s adsorptive capabilities make the use of clays practical and effective. Three types of organophilic clays modified by cationic surfactants with the ability of one of these clays to adsorb atrazine in an aqueous medium are discussed in this work. The modification in clays was done with the surfactants cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, and dodecyltrimethylammonium chloride. The X-ray diffraction data indicated different lamellar expansions for the three organophilic clays obtained when compared to in natura clay, proving the presence of quaternary ammonium salts in the interlamellar space. There was also a decrease in the specific surface area showing less accessibility to the lamellar spaces due to the presence of surfactants. The thermogravimetric analysis showed a negative variation profile in all the clays. The adsorption test showed a better capacity for atrazine adsorption in the organophilic clay of 64% when compared with 36% of in natura clay, and it followed the Freundlich isotherm model.

Los surfactantes polimerizables son aquellos que presentan un grupo polimerizable ya sea en el extremo de la porción hidrofóbica o en el contraión. Al utilizar surfactantes polimerizables, se evita el uso de monómeros, ya que el mismo surfactante puede ser polimerizable. En este trabajo se reporta la síntesis y caracterización fisicoquímica de un surfactante polimerizable catiónico de cola sencilla, decilsulfato de anilinio (DeSAn). El DeSAn fue sintetizado por una reacción de sustitución ácido-base del decilsulfato de sodio y el clorohidrato de anilina. La zona viscoelastica en las muestras de analizadas alcanza hasta un 40%.

Traballo Fin de Máster en Enxeñaría Ambiental. Curso 2019-2020 La baja biodisponibilidad del hexaclorociclohexano (HCH) afecta a la efectividad de procesos de biorremediación de suelos contaminados por HCH. Para aumentar la solubilidad aparente del HCH y potenciar su biodisponibilidad, se estudió el efecto de la acción micelar de una gran variedad de líquidos iónicos con actividad surfactante (i.e. Surface-Active Ionic Liquids o SAILs) y surfactantes convencionales sobre la solubilidad de HCH. Se prepararon disoluciones de SAILs/surfactantes y HCH (a una concentración ca. 10 veces su límite de solubilidad) utilizando dos concentraciones distintas de SAILs/surfactantes (siempre >CMC). Los resultados varían según el isómero de HCH, el SAIL/surfactante y la concentración utilizada. De forma adicional, se estudió la ecotoxicidad de los SAILs/surfactantes en dos especies vegetales. Este estudio demuestra la potencialidad de los SAILs y surfactantes para su aplicación en biorremediación de suelos contaminados por HCH y propone varios SAILs para futuras investigaciones. The low bioavailability of hexachlorocyclohexane (HCH) affects the effectiveness of bioremediation processes of HCH-contaminated soils. The effect of the micellar action of a variety of surfactant-active ionic liquids (i.e. SAILs) and conventional surfactants on the apparent solubility of HCH and its bioavailability was studied. Solutions of SAILs/surfactants and HCH (at a concentration ca. 10 times its solubility limit) were prepared using two different concentrations of SAILs/surfactants (always >CMC). The results varied according to the HCH isomer, the SAIL/surfactant and the concentration used. Additionally, the ecotoxicity of SAILs/surfactants was studied in two plant species. This study demonstrates the potential of SAILs and surfactants for their application in bioremediation of HCH-contaminated soils and proposes several SAILs for future research.

Pesquisa sem auxílio de agências de fomento Produtos à base de fungos entomopatogênicos como Beauveria spp. são reconhecidos por sua efetividade no controle de insetos pragas, devido a capacidade de adesão a cutícula do inseto através das hidrofobinas. Mas a hidrofobicidade do fungo dificulta o desenvolvimento de formulações comprometendo a eficiência da aplicação. Faz-se necessário o uso de tensoativos para reduzir a tensão superficial, mas muitos são prejudiciais aos microrganismos. O objetivo deste trabalho é selecionar tensoativos compatíveis com Beauveria bassiana e ao mesmo tempo reduzir a tensão superficial para desenvolvimento de formulação pó solúvel em água. Na primeira parte deste trabalho, preparou-se formulações usando 25 surfactantes diferentes, as quais foram testadas quanto à viabilidade após 30 dias de armazenamento a 25°C. Seis surfactantes forneceram os melhores resultados e foram selecionados para a continuação do trabalho. Assim, novas formulações foram preparadas e avaliadas quanto à tensão superficial, tempo de umectação, germinação de conídios, viabilidade e índice biológico durante 3 meses de armazenamento. Posteriormente, através do delineamento composto central (DCC), foi determinada a faixa ideal de concentração para os dois surfactantes selecionados. O menor tempo de umectação (1,61 min) e a menor tensão superficial (38 mN / m) foram obtidos usando o Emulsogen TS 200 a 5%. Todas as seis formulações mostraram uma diminuição na germinação após 1 mês de armazenamento. Após 3 meses de armazenamento, a formulação controle e a formulação preparada com Surfom D apresentaram taxas de germinação de 0% e 55%, respectivamente. A viabilidade mais alta (1,14 × 109 UFC/g) foi obtida com Surfom D. Realizou-se também um ensaio de índice biológico, o qual a B. bassiana foi compatível tanto com Emulsogen TS 200, quanto com Surfom D a 5%. O Emulsogen TS 200 foi o mais eficaz na redução da tensão superficial, mas diminuiu a viabilidade dos conídios. Surfom D apresentou propriedades de umectação ruins, mas aumentou a taxa de germinação de B. bassiana. A combinação dos dois surfactantes e suas concentrações foi estuda pelo DCC. A região ótima para compor uma formulação foi de cerca de 3% de cada um dos surfactantes para as variáveis de tensão superficial, tempo de umectação, germinação e UFC. A estabilidade da formulação de contendo 3% de Emulsogen TS 200 e Surfom D foi de 2 meses à temperatura ambiente (25ºC). Entomopathogenic fungal products such as Beauveria sp. formulations are recognized for their effectiveness in controlling insect pests, attributed to the ability to adhere to the insect cuticle through hydrophobins. However, because of their high hydrophobicity, fungal agents require the addition of surfactants to reduce particle aggregation during application. This study aimed to select surfactants that can improve the wettability of Beauveria bassiana formulations without affecting fungal viability. In a first experiment, formulations prepared using 25 different surfactants were tested for viability after 30 days of storage at 25 °C. Six surfactants provided the best results and were selected for further experiments. New formulations were prepared and evaluated for surface tension, wetting time, conidial germination, viability, and biological index during 3 months of storage. Subsequently, through central composite design (DCC) the optimal concentration range for the two selected surfactants was determined. The shortest wetting time (1.61 min) and lowest surface tension (38 mN/m) were obtained using Emulsogen TS 200 at 5%. All six formulations showed a decrease in germination after 1 month of storage. After 3 months of storage, the control formulation and formulations prepared using Surfom D had germination rates of 0% and 55%, respectively. The highest viability (1.14 × 109 colony-forming units/g) was obtained with Surfom D. B. bassiana was found compatible with 5% Emulsogen TS 200 and Surfom D. Emulsogen TS 200 was the most effective in reducing surface tension but decreased fungal viability and conidial germination. Surfom D showed poor wetting properties but increased B. bassiana germination rate. The combination of both surfactants seem a good option and was evaluated through DCC. The optimum region is around was 3% of each of the surfactants in the composition of a formulation for the variables surface tension, wetting time, germination and CFU. The stability of the B. bassiana formulation containing 3% Emulsogen TS 200 and Surfom D is 2 months at room temperature (25 ° C). Dissertação (Mestrado) 2022-02-17

Submitted by Neusa Fagundes (neusa.fagundes@unioeste.br) on 2020-10-09T18:37:45Z No. of bitstreams: 2 Lillian_Leonel2020.pdf: 4361117 bytes, checksum: 9cd9adff8da0bb3e0c2b696210dddf3a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Made available in DSpace on 2020-10-09T18:37:45Z (GMT). No. of bitstreams: 2 Lillian_Leonel2020.pdf: 4361117 bytes, checksum: 9cd9adff8da0bb3e0c2b696210dddf3a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2020-03-12 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Rice husk is a waste derived from rice milling and is an abundant byproduct in cereal producing countries. Due to the considerable contents of cellulose in its composition, it is a potential raw material for use in various bioprocesses, such as ethanol production. However, several technical challenges must be overcome to make the second-generation ethanol production process economically viable and competitive. In this context, the process of simultaneous saccharification and fermentation (SSF), associated with the increase of solids concentration, as well as the use of surfactants in enzymatic hydrolysis in fermentation processes that employ lignocellulosic biomass are promising strategies to obtain higher sugar yields and consequently ethanol. Thus, the objective of this work was to evaluate different strategies to obtain an improvement in ethanol production from rice husk cellulose, using the thermotolerant yeast Kluyveromyces marxianus ATCC 36907. The first strategy was to carry out the fed batch SSF to increase the solids load; the second was to evaluate the effect of adding nonionic surfactants during enzymatic hydrolysis in the SSF process. First, rice husk biomass was subjected to chemical characterization for cellulose, hemicellulose, and lignin content, before and after alkaline pretreatment with 8% (w/v) sodium hydroxide (NaOH). The pretreated rice husk was subjected to enzymatic hydrolysis with different enzyme loading (5, 11, 22 FPU/gcelullose) and 10% solids (w/v) to determine the condition with increased release of reducing sugars for subsequent SSF use in batch fed with high solids loading. For the SSF in fed batch, four experiments were performed with different biomass concentrations of rice husk, being E1 and E2 experiments with initial load of 10% and final 20% (w/v) and E3 and E4 with initial load 15% and final 25% (w/v), respectively, at pH 5.5; 40 °C, 200 rpm, 96 hours. Thus, feeding intervals were established, with two feedings every 24 hours (E1 and E3) and four feedings every 12 hours (E2 and E4). As a second strategy, enzymatic hydrolysis was carried out, with the objective of evaluating the effect of different enzyme loads (5; 8; 13.5; 19 and 22 FPU/gcellulose) it was evaluated in association with Polysorbate 80 (PS80) surfactants (7.0, 10, 15, 20 and 23 mg/L), Polyethylene glycol 4000 (PEG) (0.5, 1.0, 2.0, 3.0 and 3.5 g/L) and Triton X-100 (TX-100) (75; 100; 150, 200 and 225 mg/L) in glucose release through three experiments following a central rotational composite design (DCCR) 22, including 4 axial conditions and 4 center point repetitions, totaling 12 assays for each surfactant, besides a control experiment (with enzyme addition and without surfactant), in triplicate. The third strategy consisted of adding the surfactant SSF, to evaluate the influence of the surfactant in the production of ethanol. For this, three experiments were performed: control (without surfactant + 19 FPU/gcellulose), with addition of Polysorbate 80 (10.0 mg/L + 19 FPU/gcellulose) and with Polyethylene Glycol 4000 (3.0 g/L + 19 FPU/gcellulose), the type of surfactant and respective concentrations and enzyme load selected from the results of enzymatic hydrolysis that were significant. The experiments were carried out with a solids ratio of 10% (m / v), pH 5.5, 40 °C, 200 rpm, 96 hours, in triplicate. The chemical composition of rice husk was 36.03% cellulose, 14.71% hemicellulose and 26.47% lignin and after pretreatment with 8% NaOH (w/v) the content of these fractions was 70.27; 8.39 and 21.34% cellulose, hemicellulose, and lignin, respectively. In the fed batch SSF with high solids loading, an ethanol production was obtained of 9.57; 9.92; 13.99 and 12.77 g/L, yields (YE/C) of 0.16; 0.17; 0.18 and 0.18 g/g and volumetric productivity (QP) of 0.27; 0.28; 0.39 and 0.53 g/L.h-1 for the experiments E1, E2, E3 and E4, respectively. For the enzymatic hydrolysis, glucose concentrations ranged from 32.36 to 79.57 g/L with PS80 addition, from 45.14 to 74.60 g/L with PEG and 32.28 to 47.89 g/L with addition of TX-100, while the control showed from 20.36 to 47.77 g/L in 96 hours. Only the ix surfactants PS80 and PEG in association with different enzyme loads promoted significant effects (p

Os corantes alimentares são compostos potencialmente prejudiciais à saúde humana e, por isso, devem ser quantificados. O presente trabalho descreve o desenvolvimento e a validação de um método analítico para a determinação simultânea de corantes alimentares em polpa de fruta. Os analitos foram o amarelo crepúsculo, eritrosina, laranja G, tartrazina, vermelho N em polpa de goiaba utilizando sistema de Cromatografia Líquida de Alta Eficiência acoplada a detector de arranjo de diodos (CLAE-DAD). O preparo de amostra consistiu em uma massa de amostra (5,0 g), que teve o seu pH inicial ajustado (pH = 10,0), seguido de extração com acetonitrila (5,0 mL) assistida por ultrassom (5 minutos). A amostra foi centrifugada (4000 rpm, por 20 minutos a 20 oC) e teve seu pH final ajustado (pH = 3,0). Posteriormente, a amostra foi filtrada e, devido às interações entre os analitos em solução, foi necessária uma diluição do extrato adicionando o surfactante Tween 20 (2,5 x 10 -36 g mL -1 ) na etapa anterior à injeção (600 μL de amostra e 400 μL de solução de surfactante). O método foi validado, sendo as curvas analíticas preparadas em matriz, na faixa de 50 a 150 mg kg -1 para todos os analitos estudados (R 2 > 0,99). A veracidade do método foi avaliada em termos de recuperação, obtendo-se recuperações de 93-110% para todos os analitos. Os coeficientes de variação de repetitividade ficaram entre 2,1 e 13,7%, enquanto para precisão intermediária os valores variaram entre 3,3 e 19,0%. Todos os parâmetros foram aceitáveis (recuperação entre 70-120% e CV repe e CV repro menores que 14 e 20%, respectivamente) para todos os analitos, exceto para eritrosina no terceiro nível (150 mg kg -1 ). Os limites de detecção e quantificação foram determinados, sendo 15 mg kg -1 e 30 mg kg -1 , respectivamente. Os valores de limite de decisão (CC α ) e de capacidade de detecção (CC β ) variaram entre 0,81000 e 107,82 mg kg -1 e 1,6200 e 115,65 mg kg -1 , respectivamente. Os valores das incertezas relativas combinadas variaram entre 2,81 e 13,8%. Foram analisadas oito amostras de polpa de goiaba adquiridas em diferentes regiões de Minas Gerais, sendo que estas amostras não apresentaram contaminação. Conclui-se que a metodologia desenvolvida pode ser aplicada para análise de corantes em polpas de frutas de forma simples, rápida e eficiente, tornando-o adequado para monitoramento da qualidade de polpas de frutas em análises de rotina. Palavras-chave: Corantes alimentares. Análise multirresíduo. Extração assistida por ultrassom. Surfactante. CLAE-DAD. Food colors are compounds that are potentially harmful to human health and, therefore, must be quantified. The present work describes the development and validation of an analytical method for the simultaneous determination of food dyes in fruit pulp. The analytes were twilight yellow, erythrosine, orange G, tartrazine, red N in guava pulp using High Performance Liquid Chromatography system coupled to a diode array detector (HPLC-DAD). The sample preparation consisted of a sample mass (5.0 g), which had its initial pH adjusted (pH = 10.0), followed by extraction with acetonitrile (5.0 mL) assisted by ultrasound (5 minutes). The sample was centrifuged (4000 rpm, for 20 minutes at 20 oC) and its final pH was adjusted (pH = 3.0). Subsequently, the sample was filtered and, due to the interactions between the analytes in solution, a dilution of the extract was necessary by adding the surfactant Tween 20 (2.5 x 10 -36 g mL -1 ) in the step prior to injection (600 μL of sample and 400 μL of surfactant solution). The method was validated, with the analytical curves being prepared in a matrix, in the range of 50 to 150 mg kg -1 for all the analytes studied (R 2 > 0.99). The veracity of the method was evaluated in terms of recovery, with recoveries of 93-110% for all analytes. The variation coefficients of repeatability were between 2.1 and 13.7%, while for intermediate precision the values varied between 3.3 and 19.0%. All parameters were acceptable (recovery between 70-120% and CV repe and CV repro less than 14 and 20%, respectively) for all analytes, except for erythrosine at the third level (150 mg kg -1 ). The limits of detection and quantification were determined, being 15 mg kg -1 and 30 mg kg -1 , respectively. The decision limit (CC α ) and detection capacity (CC β ) values ranged between 0.81000 and 107.82 mg kg -1 and 1.6200 and 115.65 mg kg -1 , respectively. The values of the combined relative uncertainties ranged between 2.81 and 13.8%. Eight samples of guava pulp acquired in different regions of Minas Gerais were analyzed, and these samples showed no contamination. It is concluded that the developed methodology can be applied to the analysis of dyes in fruit pulps in a simple, fast and efficient way, making it suitable for monitoring the quality of fruit pulps in routine analyzes. Keywords: Food dyes. Multiresidue analysis. Ultrasound-assisted extraction. Surfactant. CLAE-DAD.

Debido a su gran versatilidad, los surfactantes son ampliamente utilizados en aplicaciones domésticas e industriales, sin embargo, tras su uso se descargan en los sistemas de alcantarillado o directamente en las aguas superficiales, afectando la biota marina. A partir de este panorama surge la necesidad de generar surfactantes cuya biodegradabilidad, biocompatibilidad y baja toxicidad sean características. Los surfactantes derivados de aminoácidos son una alternativa a esta problemática ya que son fáciles de sintetizar, tienen baja toxicidad y alta degradabilidad. Por ello el proyecto, busca proponer una metodología que permita la síntesis de un surfactante a partir de la reacción entre derivados de L-arginina, cloruro de palmitoílo y ácido palmítico, haciendo uso de condiciones Schotten Baumann y de N, N'-diciclohexilcarbodiimida respectivamente. Primero se obtuvo el derivado esterificado de L-arginina con un rendimiento de 88 %, la identidad del compuesto fue confirmada por medio de espectroscopia infrarroja y espectrometría de masas. Posteriormente, con el intermediario obtenido se realizó la reacción de obtención del surfactante por las dos metodologías planteadas, sin embargo, ninguna resulto ser eficiente en la obtención del compuesto deseado ya que se obtuvo subproductos indeseados, probablemente por problemas con la desactivación del cloruro de palmitoílo, el control estricto del pH en la reacción, la presencia de agua y las reacciones laterales existentes.

Polymers are one of the most used compounds in the chemical industry because they have application in a wide variety of products for daily use. Polymer preparation and its analysis is a very active field of research in universities and research centers in chemistry and chemical engineering around the world. There are many possible fields of research around the chemistry of polymers, including their chemical characterization, molecular weight analysis (PM) and molecular weight dispersion (DPM). These parameters also modify the physicochemical properties of the polymer. Unlike the low molecular weight molecules in which all have the same weight, and so the weight is unique and exact, in the case of polymers the molecular weight of the polymer results from the molecular weight means of the discrete molecules that compose it. Many physicochemical properties such as resistance to degradation, flexibility of a plastic, compatibility between different plastic materials of different chemical nature, behavior against temperature, among others, they are directly related not only to chemical nature of the polymer, but also with its molecular weight and the molecular weight dispersion of discrete molecules that compose the polymer. Therefore, not only the chemical nature but also the determination of molecular weight and the dispersion of weights are necessary to characterize the polymer and to understand its properties. The present study is based on the development of methodologies using GPC for the analysis of the PM and the DPM of different polymers used in the company Concentrol, as well as other polymers that are currently synthesized or that can be synthesized in the future, to contribute an improvement in the quality of analysis of products manufactured in Concentrol thus giving a higher level of quality in their products, allowing for the company be more competitive in the market. On the other hand, a family of these polymers that Concentrol uses and manufactures are silicone stabilizers for polyurethane foam, surfactants. This thesis includes the synthesis and characterization of a wide set of polymers for the production of surfactants including themselves, and the subsequent evaluation of these in different polyurethane systems, in order to find the relationship between molecular weight and surfactant structure with the final properties of the foams with the aim of designing new surfactants that are better or providing new properties to the polyurethane foams. The synthesis chemistry of surfactants in the industry is currently based on platinum catalysts. In this doctoral thesis the synthesis of catalysts based in non-precious metals for the synthesis of surfactants has been investigated, in order to replace the current platinum ones Els polímers són uns dels compostos més àmpliament utilitzats en la indústria química perquè tenen aplicació en multituds de productes d’ús quotidià. La preparació i l’anàlisi de polímers constitueix un camp de recerca molt actiu en universitats i centres de recerca en química i enginyeria química de tot el mon. Hi ha molts possibles camps d’investigació al voltant de la química dels polímers, entre ells, la seva caracterització química, l’anàlisi del seu pes molecular(PM) i la seva dispersió (DPM). Aquests paràmetres defineixen les propietats físico-químiques del polímer. A diferència de les molècules de baix pes molecular en les que totes tenen el mateix pes, i per tant el pes és únic i exacte, en el cas dels polímers el pes molecular resulta d’una mitjana dels pesos moleculars de les molècules discretes que el componen. Moltes propietats físico-químiques com la resistència a la degradació, la flexibilitat d’un plàstic, la compatibilitat entre diferents materials plàstics de naturalesa química diferent, el comportament enfront la temperatura, entre d’altres, estan directament relacionades no només amb la naturalesa química del polímer, si no també amb el seu pes molecular i la dispersió de pesos moleculars de les molècules discretes que formen el polímer. Per tant, no només la naturalesa química sinó també la determinació del pes molecular i la dispersió de pesos són necessaris per a caracteritzar el polímer i entendre les seves propietats. El present estudi es basa en el desenvolupament de metodologies mitjançant GPC per a l’anàlisi del PM i de la DPM de diferents polímers utilitzats a l’empresa Concentrol així com altres polímers que es sintetitzen actualment o que es puguin sintetitzar en un futur, a fi d’aportar una millora a la qualitat d’anàlisis dels productes fabricats actualment a Concentrol donant així un nivell major de qualitat superior en els seus productes, permetent que l’empresa sigui més competitiva en el mercat. Per altre banda, una família d’aquests polímers que utilitza i fabrica Concentrol son els estabilitzadors de silicona per a espuma de poliuretà, surfactants. Aquesta tesis recull la síntesis i caracterització d’un ampli conjunt de polímers per a la producció de surfactants inclosos ells mateixos, i la posterior avaluació d’aquests en diferents sistemes de poliuretà, a fi de trobar la relació entre el pes molecular i l’estructura dels surfactants amb les propietats finals de les espumes per tal de dissenyar nous surfactants que millorin o proporcionin noves propietats a les espumes de poliuretà. La química de síntesis dels surfactants en l’industria actualment es basa amb catalitzadors de platí. En la present tesis doctoral s’ha investigat en la síntesis de catalitzadors basats amb metalls no preciosos per a la síntesis dels surfactants per poder substituir als actuals de platí Programa de Doctorat en Química

Recently, interest in the use of solid residues to partially replace some of the concrete components has grown. In this regard, this work evaluated the effect of surface treatment of post-consumer ...

The stabilization of nanocellulose suspensions and their compatibility with polymer matrices are challenges that have been investigated in the scientific community. However, little work has resulted in significant electrostatic stabilization as well as improved the mechanical behavior of nanocomposites. Anionic surfactant modified nanocellulose, and the results demonstrated the impact of the concentration of this surfactant on nanocellulose surfaces and properties. The variation in electrostatic stability was evaluated by the zeta potential, which is key to the comprehension of dispersion and agglomeration in suspensions. Also, physicochemical tests were conducted to analyze the properties of nanocelluloses. The addition of the surfactant and its effects were verified by physicochemical characterization; it was evaluated the crystallinity, thermal stability, composition, adsorption effect, and other properties. Mechanical, thermal and physicochemical tests were conducted to understand the influence of nanoparticles on nanocomposites. The results of this study demonstrated that the surfactant-modified cellulose nanostructures presented excellent electrostatic and thermal stability, which made the developed materials potential reinforcing agents for the incorporation of polymeric matrices. These modified CNSs were incorporated in a poly(butylene adipate-co-terephthalate), and improvements of its mechanical properties were observed. Also, the thermal stability of the polymer was maintained, and the water diffusion coefficient was reduced, favoring applications that need this characteristic, like plastic packaging.

Fire suppressors are widely used in firefighting and their chemical composition may present a mixture of perfluorochlorinated surfactants (PFCs), including the perfluorooctane sulfonate (PFOS) which has been internationally banned due to its classification as a persistent organic pollutant (POP). PFCs have been found in environmental matrices and soft tissues of organisms, but the potential effect of such compounds on marine organisms has been overlooked. Here, it was evaluated whether the chronic exposures (i.e., seven days) to the fire suppressors Ageofoam, Cold Fire, Kidde and Argus could affect the reproduction of the copepod Nitocra sp. The tested concentrations consisted of those recommended on the products’ manuals and those ranging between 0.0001% and 1%. For each compound, the effective concentrations to 50% exposed organisms (EC50) and the lowest observed effect concentrations (LOEC) were estimated. All the fire suppressors exhibited high toxicity, causing fecundity reduction. At the recommended dilutions, 100% lethality occurred for all compounds. The EC50 values ranged from 0.00817% - Ageofoam - to 0.03081% - Argus. The LOECs ranged from 0.001% - Ageofoam - to 0.1% - Argus and Kidde; and were much lower than the concentrations recommended for commercial use. The fire suppressors showed high toxicity to the copepod, reducing the reproduction rates, even in very low concentrations, suggesting that the release of such substances in the estuary caused severe effects to the environment. This assessment provides subsides to the environmental regulation of fire suppressors in Brazil, because these compounds do not have national regulations for their use and disposal. RESUMEN Los supresores de incendios son usados ampliamente en la lucha contra incendios y su composición química puede presentar una mezcla de tensioactivos perfluoroclorados (PFC), incluido el sulfonato de perfluorooctano (PFOS) que ha sido prohibidos internacionalmente debido a su clasificación como un contaminante orgánico persistente (POP). Se han encontrado PFC en matrices ambientales y tejidos blandos de organismos, pero se ha pasado por alto el efecto potencial de tales compuestos en los organismos marinos. Aquí, se evaluó si las exposiciones crónicas (es decir, siete días) a los supresores de fuego Ageofoam, Cold Fire, Kidde y Argus podrían afectar la reproducción del copépodo Nitocra sp. Las concentraciones probadas consistieron en las recomendadas en los manuales de los productos las cuales oscilan entre 0.0001% y 1%. Para cada compuesto, se estimaron las concentraciones efectivas al 50% de organismos expuestos (CE50) y el efecto de las concentraciones más bajas observadas (LOEC). Todos los supresores de incendios exhibieron alta toxicidad, causando una reducción de la fecundidad. A las diluciones recomendadas, se produjo un 100% de letalidad para todos los compuestos. Los valores de CE50 variaron de 0.00817% - Ageofoam - a 0.03081% - Argus. Los LOEC variaron de 0.001% - Ageofoam - a 0.1% - Argus y Kidde; y fueron mucho más bajas que las concentraciones recomendadas para uso comercial. Los supresores de incendio mostraron una alta toxicidad para el copépodo, reduciendo las tasas de reproducción, incluso en concentraciones muy bajas, lo que sugiere que la liberación de tales sustancias en el estuario causó graves efectos en el medio ambiente. Esta evaluación proporciona insumos a la regulación ambiental de los supresores de incendios en Brasil, porque estos compuestos no tienen regulaciones nacionales para su uso y eliminación.

The use of low-cost substrates and wastes as fermentative media is a simple strategy for overcoming excessive production costs of bioactive molecules and to make the process more profitable. In this context, the aim of this work was to optimize the production of biosurfactant by Lactococcus lactis CECT-4434 from whey and vinasse from industrial sources. For this purpose, a 24 central composite design (CCD) was proposed to maximize biosurfactant production. Besides, the ability of Lc. lactis to synthesize bacteriocin-like inhibitory substance (BLIS) was also evaluated, therefore contributing to the profitability of the biotechnological process. Results showed that whey at 15% positively influenced biosurfactant production (on average 8.9 mg/L), reducing surface tension by about 18.1 mN/m. Molecular composition of the biosurfactant was determined by Fourier transform infrared spectroscopy and nuclear magnetic resonance which confirmed the presence of carbohydrates, lipids and proteins, defining this molecule as a glycolipopeptide. Regarding the BLIS synthesis, the highest concentration of sucrose (2.0%) and the lowest vinasse level (1.0%) reduced the production of BLIS identified by the decrease in antimicrobial activity (mean inhibition zone of 10.7 mm). Conversely, the lowest sucrose concentration and highest vinasse level exerted the strongest inhibition, with a mean inhibition zone of 12.2 mm against Staphylococcus aureus CECT-239.

The process of equilibration of the tetradecane-water interface in the presence of sodium hexadecane-benzene sulfonate is studied using intensive atomistic molecular dynamics simulations. Starting as an initial point with all of the surfactants at the interface, it is obtained that the equilibration time of the interface (several microseconds) is orders of magnitude higher than previously reported simulated times. There is strong evidence that this slow equilibration process is due to the aggregation of surfactants molecules on the interface. To determine this fact, temporal evolution of interfacial tension and interfacial formation energy are studied and their temporal variations are correlated with cluster formation. To study cluster evolution, the mean cluster size and the probability that a molecule of surfactant chosen at random is free are obtained as a function of time. Cluster size distribution is estimated, and it is observed that some of the molecules remain free, whereas the rest agglomerate. Additionally, the temporal evolution of the interfacial thickness and the structure of the surfactant molecules on the interface are studied. It is observed how this structure depends on whether the molecules agglomerate or not.

The mechanical and thermal properties of cryogels depend on their microstructure. In this study, the microstructure of hydroxypropyl methylcellulose (HPMC) cryogels was modified by the addition of ionic (bis (2-ethylhexyl) sodium sulfosuccinate, AOT) and non-ionic (Kolliphor® EL) surfactants to the precursor hydrogels (30 g/L). The surfactant concentrations varied from 0.2 mmol/L to 3.0 mmol/L. All of the hydrogels presented viscous behavior (G″ &gt, G′). Hydrogels containing AOT (c &gt, 2.0 mmol/L) led to cryogels with the lowest compressive modulus (13 ± 1 kPa), the highest specific surface area (2.31 m2/g), the lowest thermal conductivity (0.030 W/(m·°C)), and less hygroscopic walls. The addition of Kolliphor® EL to the hydrogels yielded the stiffest cryogels (320 ± 32 kPa) with the lowest specific surface area (1.11 m2/g) and the highest thermal conductivity (0.055 W/(m·°C)). Density functional theory (DFT) calculations indicated an interaction energy of −31.8 kcal/mol due to the interaction between the AOT sulfonate group and the HPMC hydroxyl group and the hydrogen bond between the AOT carbonyl group and the HPMC hydroxyl group. The interaction energy between the HPMC hydroxyl group and the Kolliphor® EL hydroxyl group was calculated as −7.91 kcal/mol. A model was proposed to describe the effects of AOT or Kolliphor® EL on the microstructures and the mechanical/thermal properties of HPMC cryogels.

[ES] En esta Tesis Doctoral se presenta la obtención de productos de alto valor añadido a partir de moléculas plataforma derivadas de la biomasa tales como HMF, glicerina, ácido levulínico y alcoholes grasos. Se ha llevado a cabo la síntesis de dioles con interés como monómeros para la obtención de polímeros biodegradables mediante acetalización del HMF con glicerina utilizando aluminosilicatos micro y mesoporosos como catalizadores ácidos heterogéneos. Los resultados obtenidos mostraron que la zeolita bidimensional (ITQ-2) y el material mesoporoso estructurado (MCM-41) poseen las características adecuadas para dicha reacción, pu-diendo llevarse a cabo el proceso deseado con una excelente conversión y selectividad a los acetales cíclicos. El estudio se ha podido extender al em-pleo de diferentes compuestos furánicos y glicoles. Por otra parte, se ha obtenido una nueva familia de surfactantes no iónicos derivados del HMF, mediante un proceso multietapa, que consiste en la eterificación selectiva de HMF con un alcohol graso dando lugar a un 5-alcoximetilfurfural, que posteriormente, se acetaliza con glicerina en pre-sencia de un catalizador ácido heterogéneo. El estudio mostró que la zeoli-ta BetaF, sintetizada en medio fluoruro y con una relación Si/Al = 100, po-see las propiedades de acidez y adsorción óptimas para llevar a cabo el proceso obteniéndose rendimientos y selectividades excelentes y minimi-zando al mismo tiempo la desactivación del catalizador. La zeolita Be-taF(100) se ha empleado con excelentes rendimientos en el proceso multi-etapa utilizando diferentes alcoholes grasos. Dichos compuestos surfactan-tes presentan valores de HLB comprendidos entre 4.9-6.6, y buena estabili-dad térmica, por lo tanto, podrían ser empleados como emulsionantes de agua en aceite (W/O) para diversas aplicaciones industriales. También, se ha llevado a cabo la síntesis de furfuril aminas N-sustituidas (productos de interés farmacológico), mediante aminación reductiva de aldehídos furánicos con aminas en presencia de catalizadores heterogé-neos basados en nanopartículas de Pd soportadas sobre carbón activo. El catalizador de Pd/C óptimo, con una carga metálica del 1 % en peso y un tamaño de partícula de 2.7 nm resultó ser estable y reusable en la reac-ción de aminación reductiva de HMF con diferentes aminas y amoniaco, así como, en la reacción en cascada utilizando nitrobenceno, para obtener diferentes 5-(hidroximetil)-2-furfuril aminas N-sustituidas con excelentes rendimientos y selectividades. Por último, se ha llevado a cabo síntesis quimioselectiva de precursores de surfactantes (4-alcoxipentanoatos de metilo) mediante eterificación reduc-tiva del levulinato de metilo con alcoholes grasos. Para ello se han em-pleado nanopartículas de paladio sobre diferentes soportes como cataliza-dor. Los catalizadores de Pd/C proporcionan los mejores resultados, siendo el catalizador óptimo el que presenta una carga metálica del 2.5 % en peso y tamaño de cristal alrededor de 10 nm. Se han obtenido surfactantes aniónicos mediante la saponificación de los 4-alcoxipentanoatos con exce-lentes propiedades tensioactivas. Además, la eterificación reductiva se ha extendido a otros compuestos carbonílicos y alcoholes grasos, todos ellos derivados de la biomasa para la obtención de biolubricantes con excelentes resultados., [CA] En aquesta Tesi Doctoral es presenta l'obtenció de diferents productes d'un alt valor afegit partint de molècules plataforma derivades de la biomassa, tals com HMF, glicerina, àcid levul·linic i alcohols grassos. S¿ha dut a terme la síntesi de diols amb interés com monòmers per a l'obtenció de polímers biodegradables mitjançant l'acetalització de HMF amb glicerina. Els resultats obtinguts mostraren que la zeolita bidimensional (ITQ-2) i el material mesoporós (MCM-41) presenten les característiques adequades en aquesta reacció, podent dur-se a terme el procés desitjat amb una excel·lent conversió i selectivitat als acetals cíclics. L'estudi s'ha pogut estendre a l'ús de diferents compostos furànics i glicols. Per un altre costat, s'ha obtingut una nova família de surfactants no iònics derivats del HMF, mitjançant un procés multietapa que consisteix en l'eterificació selectiva del HMF amb un alcohol gras per donar un 5-alcoximetilfurfural, que posteriorment s'acetalitza amb glicerina en presència d'un catalitzador àcid heterogeni. L'estudi va mostrar que la zeolita BetaF, sintetitzat en medi fluorur amb una relació Si/Al = 100, posseeix les propietats d'acidesa i adsorció òptimes per a dur a terme el procés obtenint-se rendiments i selectivitats excel·lents, minimitzant al mateix temps la desactivació del catalitzador. La zeolita BetaF(100) s'ha empleat amb excel·lents rendiments en el procés multietapa utilitzant diferents alcohols grassos. Aquests compostos surfactants presenten valors de HLB compresos entre 4.9-6.6, i bona estabilitat tèrmica, per tant, podrien ser empleats com emulsionants d'aigua en oli (W/O) per a diverses aplicacions industrials. En altre capítol d'aquesta tesi, s'ha dut a terme la síntesi de furfuril amines N-substituïdes (productes d'interés farmacològic), per mitjà de l'aminació reductiva d'aldehids furànics amb amines en presència de catalitzadors heterogenis basats en nanopartícules de Pd sobre carbó actiu. El catalitzador de Pd/C òptim, amb una càrrega metàl·lica de l'1 % en peso i una grandària de partícula de 2.7 nm va resultar ser estable i reusable en la reacció d'aminació reductiva de HMF amb diferents amines i amoníac, així com, en la reacció en cascada utilitzant nitrobenzé, per a obtenir diferents 5-(hidroximetil)-2-furfuril amines N-substituïdes amb excel·lents rendiments i selectivitats. Per últim, s'ha dut a terme la síntesi quimioselectiva de precursors de surfactants (4-alcoxipentanoats de metil) mitjançant eterificació reductiva del levulinato de metil amb alcohols grassos. S'han emprat nanopartícules de pal·ladi sobre diferents suports com catalitzadors. Els catalitzadors de Pd/C proporcionen els millors resultats, sent el catalitzador òptim aquell que presenta una càrrega metàl·lica del 2.5 % en peso i grandària de cristall al voltant de 10 nm. S'han obtingut surfactants aniònics mitjançant la saponificació dels 4-alcoxipentanoats amb excel·lents propietats tensioactives. A més, l'eterificació reductiva s'ha estés a altres compostos carbonílics i alcohols grassos, tots ells derivats de la biomassa per a l'obtenció de biolubricants amb excel·lents resultats., [EN] This Doctoral Thesis presents different improved catalytic pathways to-wards the production of high added value chemicals from platform mole-cules derived from biomass such as HMF, glycerol, levulinic acid and fatty alcohols. First, the synthesis of diols has been studied since they show great interest as monomers for the production of biodegradable polymers. These diols have been obtained by acetalization of HMF with glycerol using micro and mesoporous aluminisilicates as heterogeneous acid catalyst. The results obtained showed that the two-dimensional zeolite (ITQ-2) and the struc-tured mesoporous material (MCM-41) have the appropriate characteristics required for this reaction. The desired process can be carried out with an excellent conversion and selectivity to cyclic acetals. The study has been extended to the use of different furanic compounds and glycols. Secondly, a new family of non-ionic surfactants derived from HMF has been obtained by a multi-stage process. On the first step, the selective etherification of HMF with a fatty alcohol is carried out obtaining 5-alcoxymethylfurfural which is subsequently acetalized with glycerol in the presence of a heterogeneous acid catalyst during the second step. The study showed that zeolite BetaF synthesized in a fluoride medium and with a Si/Al = 100 ratio provides the optimal acidity and adsorption properties to carry out the process obtaining excellent yields and selectivities while min-imizing the deactivation of the catalyst. Next, BetaF(100) zeolite has been used with excellent yields in the multi-stage process using different fatty alcohols. These surfactant compounds present HLB values between 4.9-6.6 and good thermal stability, therefore, they could be used as water-in-oil (W/O) emulsifiers for diverse industrial applications. Thirdly, N-substituted furfuryl amines (products of high interest for phar-macology) have been synthetized by reductive amination of furanic alde-hydes with amines in the presence of heterogeneous catalysts. These cata-lysts are based on Pd nanoparticles supported on active carbon (Pd/C). The optimal Pd/C catalyst, with a metallic load of 1 % by weight and a particle size of 2.7 nm showed high stabillity and reusability in the reductive amina-tion reaction of HMF with different amines and ammonia, as well as, in the cascade reaction with nitrobenzene, to obtain different 5-(hydroxymethyl)-2-furfuryl N-amines substituted with excellent yields and selectivities. Finally, chemoselective synthesis of surfactant precursors (methyl 4-alcoxypentanoates) has been carried out by reductive etherification of me-thyl levulinate with fatty alcohols. For this purpose, palladium nanoparti-cles have been used on different supports as a catalyst. The Pd/C catalysts show the best results. Different metallic loadings were tested, being the optimal the catalyst with 2.5 % in weight and crystal size around 10 nm. By employing this catalyst anionic surfactants have been obtained by saponifi-cation of 4-alcoxypentanoates with excellent surfactant properties. In addition, reductive etherification has been extended to other carbonyl compounds and fatty alcohols, all derived from biomass to obtain biolubri-cants with excellent results., En primer lugar, me gustaría agradecer al Instituto de Tecnología Química como institución y más concretamente a las personas responsables que me otorgaran la beca predoctoral Severo Ocho “La Caixa” la cual, me ha permitido llevar a cabo el desarrollo de mi Tesis Doctoral. Extender este agradecimiento a la entidad de La Caixa por su programa de becas.

Lipases são classificadas como hidrolases e apresentam função de catalisar reações de hidrólise total ou parcial de triglicerois em diacilglicerois, monoglicerois e liberando ácidos graxos livres e glicerol em uma interface óleo-água. Estas enzimas são obtidas através do cultivo sólido ou em cultivo submerso. A fermentação submersa é utilizada na produção de enzimas em virtude das vantagens de operação mais eficiente em relação a pH, temperatura, taxa de oxigênio, relação carbono nitrogênio. No presente estudo objetivou-se estudar as melhores condições de cultivo submerso para a produção de lipase a 30°C e 150 rpm durante 48 h de cultivo pela levedura Yarrowia divulgata, utilizando-se experimentos fatoriais (DCCR) para se avaliar o efeito das variáveis, concentração de óleo e pH, utilizando óleo de oliva e óleo de soja residual como fontes de carbono. A produção de lipase foi comparada nos 2 óleos e a melhor condição encontrada foi utilizada para a avaliação da produção da lipase em biorreator de bancada a 28°C durante 72h de cultivo com variação da agitação entre 200 e 400 rpm. Foi avaliada também a influência da adição de surfactantes e emulsificantes (Tween 20, lecitina de soja e goma xantana) na produção da lipase. A lipase produzida foi caracterizada quanto a atividade e estabilidade em diferentes temperaturas, pH, íons metálicos e quanto ao efeito de solventes e surfactante na atividade enzimática. Os resultados obtidos no DCCR (22) indicam que, entre as fontes de carbono testadas, o óleo de oliva proporcionou maior produção, com atividade de 67,0 U.mL-1 em pH 5.3 e 9,97 g.L-1 de óleo. Utilizando óleo de soja residual a produção de lipase foi de 36,0 U.mL-1 em pH 5.0 e 16,22 g.L-1 de óleo. Na comparação entre os dois óleos, a atividade foi maior em óleo de oliva (57,0 U.mL-1) em comparação ao óleo de soja residual (30,8 U.mL-1). Os ensaios em biorreator de bancada utilizando óleo de oliva como fonte de carbono apresentaram resultados mais expressivos de atividade lipolítica em agitação de 300 rpm (2,939 U.mL-1) e a maior contagem celular (2,56x109 células.mL-1) foi obtida em 400 rpm, após 48h de cultivo. Os ensaios a 200 rpm apresentaram menor atividade e menor acúmulo de células durante 72h de cultivo. O EEB apresentou estabilidade em faixa de pH 3.0 a 8.0, com atividade lipolítica acima de 50% e de pH 3.0 a 6.0 com atividade residual próxima dos 100%. O íon Mn2+ foi o único responsável por proporcionar ativação do EEB nas concentrações de 5mM e 10mM e os íons Mg2+, Zn2+ e Ca2+ apresentaram efeito de ativação do EEB apenas em concentração de 5mM. Os surfactantes influenciaram de forma negativa na atividade lipolítica, com exceção do Triton X-100 (1%). Os solventes orgânicos apresentaram ativação da lipase apenas em 1% e o DMSO apresentou influência positiva em 1% e 10%. Lipases are classified as hydrolases and have the function of catalyzing reactions of total or partial hydrolysis of triglycerones in diacylglycerols, monoglycerols and liberating free fatty acids and glycerol in an oil-water interface. These enzymes are obtained through solid culture or in submerged culture. The submerged fermentation is used in the production of enzymes due to the advantages of more efficient operation in relation to pH, temperature, oxygen ratio, carbon /nitrogen ratio. The objective of this work was to study the best conditions of submerged culture for the production of lipase at 30 °C and 150 rpm for 48 h of culture by yeast Yarrowia divulgata, using factorial experiments (DCCR) to evaluate the effect of the variables, oil concentration and pH, using olive oil and residual soybean oil as carbon sources. Lipase production was compared in the 2 oils and the best condition found was used for evaluation of lipase production in bench bioreactor at 28 °C for 72 h of culture with stirring variation between 200 and 400 rpm. The influence of the addition of surfactants and emulsifiers (Tween 20, soy lecithin and xanthan gum) on lipase production was also evaluated. The lipase produced was characterized as the activity and stability at different temperatures, pH, metal ions and the effect of solvents and surfactant on the enzymatic activity. The results obtained in the DCCR (22) indicate that, among the carbon sources tested, olive oil provided higher production, with activity of 67.0 U.mL-1 at pH5.3 and 9.97 g.L-1 of oil. Using residual soybean oil the lipase production was 36.0 U.mL-1 at pH 5.0 and 16.22 g.L-1 oil. In the comparison between the two oils, the activity was higher in olive oil (57.0 U.mL-1) compared to residual soybean oil (30.8 U.mL-1). The assays in bench-top bioreactor using olive oil as carbon source showed more expressive results of 300 rpm (2.939 U.mL-1) agitated lipolytic activity and the highest cell count (2.56x109 cells.mL-1) was obtained at 400 rpm, after 48 h of culture. The assays at 200 rpm showed less activity and less accumulation of cells during 72h of culture. EEB showed stability in the range of pH 3.0 to 8.0, with lipolytic activity above 50% and pH 3.0 to 6.0 with residual activity close to 100%. The Mn2+ ion was the only one responsible for providing EEB activation at concentrations of 5mM and 10mM, and the Mg2+, Zn2+ and Ca2+ ions presented in EEB activation effect only at 5mM concentration. Surfactants negatively influenced lipolytic activity, with the exception of Triton X-100 (1%). The organic solvents presented activation of the lipase only in 1% and DMSO had a positive influence in 1% and 10%.

Hybrids based on bentonite modified with organic cations, transition metals and silane were synthesized by different routes of synthesis and characterized by XRD, thermogravimetric analysis (TG), FTIR, XRF, TEM, SEM, elemental analysis CHN, analysis of the zeta charge potential and UV-Vis the solid state, evidencing the effective formation of the desired solids. Organobentonites were synthesized by microwave heating using three different surfactants (tetra, hexa and octadecyltrimethylammonium) with different carbon chain sizes and the modifications occurred in the bentonite structure were studied and the solids obtained were applied and evaluated in the adsorption of remazol blue RN anionic dye and the adsorption of a mixture containing three different types of anionic dyes and inorganic salts, both having satisfactory results, reaching approximately 100% of dye removal. Modified bentonites were also synthesized with the first series of transition metals (Fe2+, Fe3+, Co2+, Ni2+, Cu2+ and Zn2+) by the ion exchange process using conventional route, studying the changes occurred in the bentonite structure after incorporation and the solids were subsequently applied in the adsorption of the remazol blue RN anionic dye, for the iron-containing solids presented better adsorption results. Some factors were evaluated that may significantly influence the adsorption capacity, such as pH, adsorbent dosage, contact time and initial concentration of the dye solution. Finally, bentonites were silanized with 3-chloropropyltrimethoxysilane and submitted to subsequent reactions with 2-aminothiazole and 2-thiazoline-2-thiol in order to obtain hydrophobic materials. The hydrophobic character of the hybrids obtained by the subsequent reactions was confirmed by the wettability test by calculating the contact angle. All the results were promising, suggesting scientific and technological potential for the solids presented here. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Híbridos baseados em bentonitas modificadas com organocátions, metais de transição e silano foram sintetizados por diferentes rotas de síntese e caracterizados por DRX, análise termogravimétrica (TG), FTIR, FRX, MET, MEV, análise elementar de CHN, análise do potencial zeta e UV-Vis do estado sólido, evidenciando a efetiva formação dos sólidos desejados. Foram sintetizadas organobentonitas através de síntese por aquecimento em microondas utilizando-se três diferentes surfactantes (tetra, hexa e octadexiltrimetilamônio) com diferentes tamanhos de cadeia carbônica e as modificações ocorridas na estrutura da bentonita foram estudadas e os sólidos obtidos foram aplicados e avaliados na adsorção do corante aniônico azul de remazol RN e na adsorção de uma mistura contendo três diferentes tipos de corantes aniônicos e sais inorgânicos, apresentando em ambos os casos resultados satisfatórios, chegando a aproximadamente 100% de remoção do corante. Foram sintetizadas também bentonitas modificadas com metais da primeira série de transição (Fe2+, Fe3+, Co2+, Ni2+, Cu2+ e Zn2+ ) através do processo de troca iônica por rota convencional, estudando-se as mudanças ocorridas na estrutura da bentonita após a incorporação dos mesmos e posteriormente os sólidos foram aplicados na adsorção do corante aniônico azul de remazol RN, em que os sólidos contendo íons de ferro apresentaram melhores resultados de adsorção. Foram avaliados fatores que podem influenciar significativamente na capacidade de adsorção, como por exemplo, valor de pH, dosagem de adsorvente, tempo de contato e concentração inicial da solução do corante. Por fim, bentonitas foram silanizadas com 3- cloropropiltrimetóxissilano e submetidas a reações subsequentes com 2- aminotiazol e 2-tiazoline-2-tiol com o objetivo de se obter materiais hidrofóbicos. O caráter hidrofóbico dos híbridos foi confirmado pelo teste de molhabilidade através do cálculo do ângulo de contato. Todos os resultados foram promissores, sugerindo potencial científico e tecnológico para os sólidos aqui apresentados.

Submitted by Natasha Valladão (natashasilvaa4@gmail.com) on 2021-02-04T00:01:02Z No. of bitstreams: 1 MarcosViniciusGiroMaitam-min.pdf: 2134340 bytes, checksum: ea0dcc0ce513b7218831cca28c964a86 (MD5) Made available in DSpace on 2021-02-04T00:01:02Z (GMT). No. of bitstreams: 1 MarcosViniciusGiroMaitam-min.pdf: 2134340 bytes, checksum: ea0dcc0ce513b7218831cca28c964a86 (MD5) Previous issue date: 2019-02 As incrustações em processos de separação por membranas são caracterizadas pelo acúmulo de particulados em sua superfície e no interior de seus poros. O principal objetivo deste estudo foi o de empregar surfactantes comerciais (CTAB, SDS e Tween 80) e um biossurfactante (Ramnolipídeo) para o recobrimento da superfície de uma membrana comercial de microfiltração para melhorar seu desempenho. As membranas com e sem recobrimento foram caracterizadas quanto às suas propriedades superficiais, pelas técnicas de FT-IR, potencial zeta e ângulo de contato. Foram realizados experimentos de propensão ao fouling utilizando suspensões da levedura Saccharomyces cerevisiae como modelo de agente incrustante, em diferentes condições operacionais. Os resultados de ângulo de contato e potencial zeta comprovaram a adsorção dos surfactantes na membrana, dada a mudanças na hidrofilicidade e carga superficial. Em todas as condições de pressão e vazão volumétrica avaliadas, o desempenho do fluxo de permeado foi melhorado para as membranas recobertas em comparação à membrana sem recobrimento. Os testes de longa duração por um período de 72 horas indicaram maior estabilidade do ramnolipídeo adsorvido na superfície da membrana, sendo eficaz na redução da formação de incrustações. Fouling in membrane separation process is defined by the accumulation of particulates on membrane surface and in its pores. The main goal of this work is to use commercial surfactants (CTAB, SDS and Tween 80) and a biossurfactant (Rhamnolipid) to coat the surface of a commercial microfiltration membrane in order to improve its performance. All membranes, coated and uncoated, were characterized by their surface properties. FT-IR, zeta potential and contact angle evaluations were carried out. Microfiltration tests using Saccharomyces cerevisiae yeast suspension as fouling agent model at different operational conditions were performed. The contact angle and zeta potential results indicated the adsorption of surfactants on the membranes surface due to changes in membrane’s hydrophilicity and superficial charges. In every pressure and flow conditions set, the permeate flux values were increased for all coated membranes in comparison to the uncoated membrane. The long term experiments showed a high stability of the rhamnolipid adsorption on the membrane surface, proving its effectiveness in fouling reduction.

Orientador:Edvaldo Sabadini Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química Resumo: O objeto central de estudo deste trabalho são as micelas gigantes. Será estudada a formação, crescimento e interações dessas estruturas de autoassociação alongadas. Porém, ao invés de se alterar a composição das micelas diretamente, será avaliado o efeito do solvente nesses agregados, uma abordagem raramente empregada na área. Neste trabalho, utilizou-se primariamente dois surfactantes catiônicos (brometo de hexadeciltrimetilamônio e brometo de tetradeciltrimetilamônio) e salicilato de sódio, que juntos formam um dos sistemas de micelas gigantes mais bem estudados. De acordo com a literatura, solventes com índices de refração (n) e constantes dielétricas (?) semelhantes deveriam resultar em micelas com viscosidades similares, pois o efeito na constante de Hamaker deveria ser idêntico. Logo, foram escolhidos cinco aditivos hidrofílicos, glicerina, sacarose, 1,3-butanodiol, dimetilsulfóxido e ureia, para testar essa hipótese. Esses aditivos foram escolhidos por suas potenciais aplicações práticas, e por alguns terem sido estudados anteriormente, como ponto de comparação. Foram utilizadas misturas binárias com água, nas concentrações de 5---60% (m/m) de aditivo em água. Duas técnicas, a reologia e a calorimetria de titulação isotérmica (ITC), foram utilizadas em conjunto para analisar o efeito das mudanças no solvente nas propriedades das micelas. Os perfis de viscosidade no repouso (?0) em função da concentração de salicilato, obtidos por reologia, possuíram correlações insatisfatórias somente com n e ?, mas foram muito bem descritos pelo parâmetro de Gordon G, relacionado com a estruturação do solvente. Os perfis de viscosidade foram complementados com estudos de reologia oscilatória, onde observou-se que as micelas mantiveram sua estrutura, exceto em altas concentrações de aditivos. Os resultados calorimétricos, por sua vez, não possuíram uma correlação tão satisfatória, mas medidas simplificadas, sem salicilato de sódio, foram muito bem explicadas por esses parâmetros. Além disso, descobriu-se que ureia, em concentrações acima de 35% (m/m), induzia a formação de lamelas de três surfactantes catiônicos. Essas estruturas foram caracterizadas. Esses resultados mostram como o solvente afetou as micelas, e como efeitos inicialmente não considerados pela constante de Hamaker levam à diferenças nas propriedades micelares. Por exemplo, o efeito de glicerina deveria ser similar ao da sacarose, por possuírem n e ? praticamente idênticos, mas seus parâmetros de Gordon divergem significativamente. Isso mostra como as características estruturais únicas de cada aditivo são relevantes para a explicação completa das micelas gigantes. Foi observado que a fluorescência do salicilato era afetada pela quantidade de surfactante em solução, resultado que foi atribuído à incorporação do mesmo nas micelas, e essa propriedade foi correlacionada a viscosidade e o calor de interação, algo inédito. Com isso, foi desenvolvido um método para a medida de fluorescência resolvida no tempo, na escala de ms, para se observar a incorporação de salicilato. Infelizmente, não foi possível obter a cinética de crescimento micelar por essa técnica. Por outro lado, foi realizado espalhamento de raios-X em baixos ângulos resolvido no tempo em Grenoble, França, onde se estimou o tempo de crescimento como sendo entre 35 e 65 ms, para um sistema concentrado Abstract: The main object of study of this work are wormlike micelles. The formation, growth and interactions of these elongated self-assembly structures will be studied. However, instead of altering the composition of the micelles directly, the effect of the solvent on the micelles will be studied instead, a rarely used approach in this area. In this work, mainly two cationic surfactants were used (hexadecyltrimethylammonium bromide and tetradecyltrimethylammonium bromide), together with sodium salicylate, which form well known wormlike micelles. According to the literature, solvents with similar refractive indexes (n) and dielectric constants (?) should result in micelles with similar viscosities, because the effect on the Hamaker constant should be identical. Therefore, five hydrophilic additives were chosen, glycerol, sucrose, 1,3-butanediol, dimethylsulfoxide and urea, to test this hypothesis. These additives were chosen for their practical applications, and because some were studied previously, and could be used as reference points. Binary mixtures of these additives, with concentrations ranging from 5---60% (w/w), and water were used. Two techniques, rheology and isothermal titration calorimetry (ITC), were used in unison to analyze the effect of the changes of the solvents in the properties of the micelles. The zero-shear viscosity (?0) profiles as a function of salicylate concentration, obtained through rheology, had unsatisfactory correlations with n and ?, but were very well explained by the Gordon parameter G, which is related to the structure of the solvent. These viscosity profiles were complemented by oscillatory rheology measurements, which showed that the micelles maintained their structure, except at high additive concentrations. The calorimetric results, on the other hand, could not be satisfactorily correlated to the parameters, but the simplified experiments, without sodium salicylate, could be correlated. On top of that, it was discovered that urea, in concentrations above 35% (w/w), induced the formation of lamellae with three cationic surfactants. These structures were characterized. These results showed how the solvent affected the micelles, and how effects not considered by the Hamaker constant lead to differences in the micellar properties. For example, the effect of urea should be similar to that of sucrose, due to their similarities in both n and ?, but their Gordon parameters diverged significantly. This shows how the unique structural characteristics of each additive are relevant to explain the whole self-assembly system. It was also observed that the fluorescence of salicylate was affected by the quantity of surfactant in solution, which was attributed to its incorporation into the micelles. This was correlated with the viscosity and the heat of interaction, something novel. A ms-scale time-resolved fluorescence method was developed, to observe the incorporation of salicylate. However, the growth kinetics could not be obtained by this technique. On the other hand, time-resolved X-ray scattering was performed in Grenoble, France, where the growth of the micelles was estimated to happen between 35 to 65 ms, in the concentrated regime Doutorado Físico-Química Doutor em Ciências CNPQ 140369/2015-5 CAPES

Agradecimentos: The authors acknowledge the Brazilian agencies CNPq (grant number: 301016/2015-1), FAPESP (grant numbers: 2015/ 25406-5 and 2015/08541-6), and PETROBRAS (grant number: 2015/00103-0). We also want to thank the lab technician of the Colloids and Interfaces Group of UNICAMP, Victor Augusto Licio Garcia Vilela, for helping to perform experiments (grant number: 301016/2015-1) and Marcelo Alexandre de Farias from the Brazilian Nanotechnology National Laboratory (LNNano) for the help in the CryoTEM analysis and also LNNano to the access to the CryoTEM facilities (research proposal: TEM-24274) Abstract: The energy released when tetradecyltrimethylammonium bromide (C14TAB) is combined with different derivatives of chlorobenzoates in an isothermal titration calorimeter (ITC) allows a direct evaluation of the spontaneity of the threading of the aromatic anions into the micellar palisade. The comparison between the enthalpimetric curves with the ones for viscosity of the solutions, hydrodynamic radii of the aggregates (dynamic light scattering experiments), and the fraction of aromatic anions incorporated (diffusion-ordered spectroscopy experiments) allows the establishment of the variations of enthalpy with formation, growth, and decrease of the wormlike micelles (WLMs). The formation of WLMs with C14TAB is very favored (very exothermic) for titrations of chlorobenzoate derivatives which present the chlorine atom in positions 3 or 4 of the aromatic ring. However, the aggregation is highly unfavorable if chlorine is at position 2 of chlorobenzoate. According to the results, the high potential of the ITC to determine critical concentrations and the energies associated with the aggregation of a cationic surfactant and aromatic anions for the formation of WLMs was demonstrated FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ Fechado

29 p., Los contaminantes producidos por los hidrocarburos y metales pesados presentan diversas formas de movilización y de acumulación en los diferentes ecosistemas. Los más afectados son el suelo y el agua, y las técnicas de remediación van directamente destinadas a eliminar los contaminantes en estos medios para que no lleguen a la cadena trófica. Una técnica muy utilizada en la actualidad es el uso de surfactantes, sustancias químicas que permiten la solubilización y transporte de los contaminantes para que queden disponibles a los microorganismos encargados de la degradación. En numerosas ocasiones, los surfactantes producen una contaminación más elevada en el medio que los contaminantes iniciales, por ello, se están llevando a cabo técnicas de remediación a través de biosurfactantes, los cuales son producidos de forma natural por algunos microorganismos., The pollutants produced by hydrocarbons and heavy metals present different forms of mobilization and accumulation in different ecosystems. The most affected are the soil and water, and the remediation techniques are directly aimed at eliminating contaminants in these media so that they do not reach the food chain. A technique widely used today is the use of surfactants, chemical substances that allow the solubilization and transport of contaminants to be available to the microorganisms responsible for degradation. In many occasions, the surfactants produce a higher pollution in the environment than the initial contaminants, therefore, remediation techniques are being carried out through biosurfactants, which are produced naturally by some microorganisms., Grado en Ciencias Ambientales

Agradecimentos: The authors would like to acknowledge the support to this research by the São Paulo Research Foundation (Fundação de Amparo à Pesquisa do Estado de São Paulo - FAPESP, Brazil - Grants #2013/26534-1 and #2017/01858-0), National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq, Brazil - Grant # 307139/2015-8), Emerging Leaders in America Program (ELAP, Canada) and Natural Sciences and Engineering Research Council of Canada - Discovery Program (NSERC, Canada). This study was financed in part by the Coordination for the Improvement of Higher Educational Personnel (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES, Brazil - Finance Code 001) Abstract: Polyelectrolyte complexes of chitosan (Ch) and pectin (Pc) or alginate (Alg) were produced in the presence or absence of the silicone gel Silpuran® 2130 A/B (Sil) and the surfactant Kolliphor® P188 (Kol). Ch-Pc-Kol-based formulations presented higher porosity (up to 83.3%) and thickness (maximum of 2273.5 µm in PBS). Lower water contact angle was observed for Ch-Alg formulations (minimum of 36.8°) and these formulations presented higher swelling and mass loss in PBS (reaching up to 21.7 g/g and 80.4%, respectively). The addition of Sil to the matrices improved their elastic moduli, reaching a maximum of 4-fold change at 40% strain. The use of pectin instead of alginate augmented the elastic moduli, reaching 66 and 4-fold changes for dense and porous formulations, respectively. Pectin-containing scaffolds presented poroviscoelasticity, a typical mechanical feature of many soft tissues. The suitability of the materials for tissue engineering applications was demonstrated in terms of stability upon degradation in culture medium or lysozyme solution, as well as lack of cytotoxicity. This study evidences the potential of Ch-Pc-based materials to be further explored for this purpose, especially to improve the mechanical properties of chitosan-based scaffolds aiming medical applications CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Fechado

La cromatografía líquida (CL) de fase inversa (reversed phase liquid chromatography, RPLC) es el modo de CL más habitual en los laboratorios analíticos, debido a su amplia aplicabilidad, fiabilidad, robustez y sensibilidad. Desafortunadamente, la pérdida de eficacia (especialmente para compuestos básicos, cuyos picos anchos y asimétricos se explican principalmente por la interacción con los grupos silanol residuales aniónicos presentes en el empaquetamiento de la columna), y la retención inadecuada de diversos compuestos (demasiado cortos o excesivos), dificultan una aplicabilidad más universal de este modo cromatográfico. Desde el desarrollo de la técnica, se ha dedicado mucho esfuerzo para resolver estos problemas. Sin embargo, aún es necesario avanzar en el conocimiento de los mecanismos de separación cromatográfica, considerando sus aspectos termodinámicos y cinéticos, y mejorar las metodologías analíticas, especialmente en el campo del análisis farmacéutico y alimentario. El trabajo realizado a lo largo de la Tesis Doctoral reunió varias propuestas de dos tipos para mejorar el rendimiento en HPLC: 1. Uso de aditivos de diferente naturaleza para inducir equilibrios secundarios. A pesar de la variedad de columnas disponibles en el mercado, su química aún es limitada. Sin embargo, al añadir aditivos a la fase móvil, el rango de selectividades de las columnas comerciales en RPLC puede aumentar y puede lograrse una mejora en su rendimiento. Se realizaron varios estudios que han profundizado en el conocimiento de los factores que producen el ensanchamiento y la distorsión de las señales cromatográficas, y se desarrollaron estrategias que mejoran el perfil de los picos cromatográficos y la resolución. Los aditivos investigados fueron los tensioactivos dodecilsulfato de sodio (SDS) y varios tensioactivos no iónicos de la familia del Brij-35 (añadidos a la fase móvil por encima de su concentración micelar crítica, en la llamada cromatografía líquida micelar o CLM), así como los líquidos iónicos (ionic liquids, ILs) formados por el catión 1-hexil-3-metil imidazolio asociado a cloruro y tetrafluoroborato. A lo largo del desarrollo de la Tesis Doctoral, se pretendía: • Minimizar los efectos indeseables de los silanoles residuales en columnas de. Con este objetivo, los aditivos citados se adsorbieron en la fase estacionaria, formando una capa protectora que enmascara el acceso de solutos básicos a los grupos silanol residuales, dando lugar a una mejora en la forma de sus picos cromatográficos (anchura y asimetría). • Lograr avances en la aplicación de la CLM. Interesaba particularmente el desarrollo de la elución en gradiente utilizando Brij-35, explorar la aplicación de nuevos tensioactivos no iónicos, y comprobar la viabilidad y las posibles ventajas del uso de mezclas de los tensioactivos aniónico SDS y no iónico Brij-35. • Investigar más a fondo el uso de ILs como aditivos de la fase móvil en CL, así como el efecto sobre el comportamiento cromatográfico del uso de diversos tampones para fijar el pH, en ausencia y presencia de ILs. • Desarrollar nuevas metodologías para el análisis de fluidos fisiológicos y productos farmacéuticos, utilizando tensioactivos e ILs como aditivos de la fase móvil. 2. Estudios sobre cromatografía líquida de interacción hidrofílica. En los últimos años, se han fabricado diversas columnas de cromatografía líquida de interacción hidrofílica (HILIC) para la determinación de compuestos de alta polaridad. HILIC es un campo de rápido crecimiento, con varios autores interesados, a lo largo de las últimas dos décadas, en la investigación de los mecanismos de retención en columnas HILIC de diferente naturaleza y la comparación de comportamientos. El grupo de investigación ha desarrollado diversas metodologías para evaluar el rendimiento de las columnas en RPLC. Se ha considerado de interés aplicarlas a columnas HILIC de diferente naturaleza. El propósito de los trabajos realizados fue: • Estudiar y comparar la retención, la forma del pico, la selectividad y la resolución en el análisis de compuestos polares, utilizando columnas HILIC disponibles en el mercado. • Explorar la modelización del comportamiento de retención en HILIC, utilizando ecuaciones de diversa complejidad, con propuestas novedosas. El trabajo ha implicado un gran esfuerzo experimental, diseñado para explorar y extraer información sobre el comportamiento cromatográfico de compuestos de diferente naturaleza (sulfonamidas, β-bloqueantes, antidepresivos tricíclicos, flavonoides, diuréticos y nucleósidos). Se ha ensayado una gran diversidad de condiciones experimentales, utilizando fases móviles acuo-orgánicas con acetonitrilo, fases móviles micelares puras e híbridas, fases móviles micelares mixtas y fases móviles que contienen ILs. Asimismo, se hizo uso de una gran variedad de columnas para RPLC y HILIC. Reversed phase liquid chromatography (RPLC) is the most usual LC mode in analytical laboratories, due to its wide applicability, reliability, robustness and sensitivity. Unfortunately, the loss of efficiency (especially for basic compounds, whose broad and asymmetrical peaks are mainly explained by the interaction with anionic residual silanol groups present in the column packing), and the inadequate retention for diverse compounds (too short or excessive), hinder a more universal applicability of this chromatographic mode. Since the development of the technique, much effort has been devoted to solve these problems. However, it is necessary to still progress on the knowledge of the chromatographic separation mechanisms, considering its thermodynamics and kinetics aspects, and improve the analytical methodologies, especially in the field of pharmaceutical and food analysis. The PhD. work gathered some proposals of two types to improve the HPLC performance: 1. Use of additives of different nature to induce secondary equilibria. In spite of the variety of columns available in the market, their chemistry is still limited. However, by adding additives to the mobile phase, the range of selectivities of the comercial columns in RPLC can increase, improving their performance. In this work, several studies are presented which have deepened on the knowledge of the factors that produce the broading and distortion of the chromatographic signals, as well as on the development of strategies that improve the profile of the chromatographic peaks and the resolution. The investigated additives were the surfactants sodium dodecyl sulphate (SDS) and several from the non-ionic Brij 35 family (added to the mobile phase above their critical micellar concentration, in the so-called micellar liquid chromatography or MLC), as well as 1-hexyl-3-methyl imidazolium ionic liquids associated to chloride and tetrafluoroborate. Throughout the development of this PhD. work, our purpose was: • Minimise the undesirable effects of the residual silanols in reversed-phase HPLC columns. With this aim, the cited additives were adsorbed onto the stationary phase, forming a protective layer that masked the access of basic solutes to the residual silanol groups, giving rise to an improvement in the peak shape (width and asymmetry). • Progress in the application of MLC. We were particularly interested in the development of gradient elution using Brij-35, exploring new non-ionic surfactants for MLC, and checking the viability and possible advantages of the use of mixtures of the anionic SDS and non-ionic Brij-35. • Further investigate the use of ionic liquids (ILs) as mobile phase additives in liquid chromatography, and the effect on the chromatographic behaviour of the use of different buffers to fix the pH, in the absence and presence of ILs. • Develop new methodologies for the analysis of physiological fluids and pharmaceuticals, using surfactants and ILs as additives of the mobile phase. 2. Studies on hydrophilic interaction liquid chromatography. In recent years, diverse hydrophilic interaction liquid chromatography (HILIC) columns have been manufactured for the determination of high polarity compounds. HILIC is a fast growing field with a number of authors interested, along the last two decades, on the investigation of the mechanisms of retention in HILIC columns of different nature and their comparison. The research group has developed diverse methodologies to investigate the column performance for RPLC. It has been considered of interest applying the developed tools to HILIC columns of different nature. Our purpose was: • Study and compare the retention, peak shape, selectivity and resolution in the analysis of polar compounds using commercially available HILIC columns of different nature. • Explore the possibility of modelling the retention behaviour in HILIC, using equations of diverse complexity. The work has implied a large experimental effort, designed to explore and extract information on the chromatographic behaviour of compounds of different nature (sulphonamides, β blockers, tricyclic antidepressants, flavonoids, diuretics and nucleosides). A great diversity of experimental conditions has been assayed, using aqueous-organic mobile phases with acetonitrile, pure and hybrid micellar mobile phases, mixed micellar mobile phases, and mobile phases containing ILs. A large variety of columns were used for RPLC and HILIC.

Orientador: Prof. Dr. Caetano Rodrigues Miranda Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Nanociências e Materiais Avançados, 2019. Para aumentar a vida útil dos reservatórios maduros, processos de recuperação melhorada de petróleo (EOR) otimizados são altamente requisitados pela indústria de óleo & gás. Neste contexto, é importante conhecer os mecanismos fundamentais que regem as interfaces fluido-fluido, que são primariamente associados a propriedades interfaciais, especialmente a tensão interfacial (IFT). No entanto, a descrição destes fenômenos experimentalmente pode ser difícil, uma vez que estas interações ocorrem em nível atômico/molecular. Para uma melhor compreensão destes mecanismos, o comportamento das propriedades interfaciais foi investigado computacionalmente na tentativa de entender os efeitos da IFT na EOR. Para atingir este objetivo, duas metodologias foram empregadas, dinâmica molecular clássica (DM) e aprendizado de máquina (AM). Para determinar a IFT nas interfaces óleo-salmoura, consideramos cinco modelos de óleo: (i) heptano, (ii) tolueno, estes monocomponentes, (iii) uma combinação 50% dos modelos anteriores (heptol), (iv) um modelo para representar um óleo leve (8 componentes) e (v) um modelo de óleo médio (36 componentes), introduzido originalmente nesta tese. Os modelos de óleo foram validados comparando-se as densidades, IFTs, viscosidades e coeficientes de difusão com dados experimentais. Para simular as interfaces entre óleo e salmoura, 26 soluções salinas foram modeladas combinando os íons Na+, K+, Ca2+, Mg2+, Cl- e SO2-4 , adicionalmente à estas soluções aquosas, foram propostos mais dois modelos multicomponentes: água do mar (com sulfato) e estendido (sem o sulfato). Os resultados obtidos com os cálculos de DM mostraram que a IFT tende a crescer com o aumento da salinidade e da pressão e reduzir com o aumento da temperatura. Também foi observado o acúmulo de aromáticos, assim como a ausência de íons na interface entre óleo e salmoura. O AM foi aplicado utilizando dois bancos de dados, um composto por valores da literatura (surfactantes) e outro com dados gerados via DM (interfaces salmoura-óleo). Os erros obtidos nos modelos de AM foram menores para o banco de dados criado com a DM, predizendo com acurácia valores da literatura não utilizados como dados de treino. Com estes resultados, foi concluído que a combinação entre DM e AM pode potencializar a proposta de novos fluidos para injeção, além de permitir novas propostas de interfaces e com isso, o estudo de novos mecanismos para a IFT. To span the lifetime of mature reservoirs, optimal enhanced oil recovery (EOR) processes are highly desired in the oil & gas industry. In this context, it is important to know the underlying mechanisms in fluid-fluid interfaces, which are mainly associated to interfacial properties, especially interfacial tension (IFT). However, the explanation of this phenomenon can be hardly accessed via experiments, because these interactions occur at the atomic/molecular level. For a better comprehension of these mechanisms, the behavior of interfacial properties was computationally investigated in an attempt to understand the effects of interfacial tension (IFT) on EOR. In order to achieve this goal, two methodologies were employed, machine learning (ML) and classical molecular dynamics (MD). To determine the IFT in the oil-brine interfaces, five models of oil were considered, being two monocomponents (heptane and toluene) and the combination of both (heptol). For more complex oils, two more models were developed: light oil (8 components), previously studied, and oil medium (36 components), originally proposed by this thesis. Oil models were validated by comparing the density, IFT, viscosity and diffusion coefficient with experimental data. To simulate the interfaces between oil and brine, 26 saline solutions were modeled by combining the ions in Na+, K+, Ca+2, Mg+2, Cl- and SO24 , moreover two multicomponent models were created: seawater (with sulphate) and extended (without sulfates). The results obtained with the MD calculations showed that the IFT tends to increase with increasing salinity and pressure, and reduce with increasing temperature. In addition, it was observed the accumulation of aromatic, as well as the absence of ions at the interface between oil and brine. The ML was applied using two databases, one composed of values from the literature (surfactants) and another with data from MD (brine-oil interfaces). The errors obtained for the ML models was lower to the dataset created with MD, predicting with accuracy several data from the literature, even data are not used to train the model. With this result, we can show that the combination between MD and ML can enhance the understanding of the role of the features in the reduction of IFT, and new systems and mechanisms can be studied using ML.