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One of the greatest challenges in the world is in the final disposal of plastics in order to reduce the effect of its polluting potential. Thus, the application of pyrolysis processes in generating products of interest such as fuel oils can be part of the solution. In addition to reducing greenhouse gas emissions to the atmosphere, oil can enter the supply chain after the cracking process in petrochemical industries. In this context, this work used statistical modeling of the response surface linked to the Normal Boundary Intersection algorithm, aiming at a higher yield of oil production and major selectivity of recycled polypropylene pyrolysis. From the analysis of the mechanisms proposed in the literature with the modeling and optimization in this work, it was possible, from a kaolin mass of 9.12 g and a heating ramp of 19.37°C/min, to obtain higher percentages of aviation kerosene as well as a satisfactory performance.

The present work presents the results of the production of vanillin-doped alginate biofilm. Alginate dressings are already a therapeutic reality, but they act only by maintaining the appropriate environment for healing. With the intention of improving their properties, the incorporation of vanillin was proposed due to its antioxidant and antimicrobial potential. Different biofilms were produced employing experiment planning through response surface analysis, which allowed determining the best region for a medium value of solubility and high degree of intumescence. This region refers to values above 0.07 g of CaCl2 and concentrations above 0.024 g of vanillin, triggering a solubility between 25% and 30% and a degree of intumescence above 100% and with fixed values of alginate (0.85 g). As for the optimization of the process, the Normal Boundary Intersection (NBI) method was able to analyze concave regions, predicting the optimal points and generating the Pareto chart with equidistant limits The antimicrobial test allowed the observation of antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa microorganisms from the biofilms, as well as a solution of vanillin with calcium chloride and glycerol obtaining a halo of inhibition only in the presence of vanillin. Thermal analysis of thermogravimetry and differential exploratory calorimetry showed that the material has thermal stability, in the temperature range ideal for application as a biomaterial, for example as biocuratives.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior A análise exergética é uma ferramenta útil para avaliar a sustentabilidade de processos biotecnológicos. A aplicação da análise exergética como estratégia para o estudo e seleção das variáveis de processo é ainda pouco explorada no campo da biotecnologia. O conhecimento da exergia química padrão dos compostos envolvidos no sistema estudado é, normalmente, necessário para a análise. No entanto, o cálculo desta propriedade termodinâmica, em muitos casos, não é trivial, uma vez que ainda existe um número limitado de dados disponíveis na literatura para biocompostos. Diante disso, esta tese apresenta uma proposta para tomada de decisão de condições operacionais de biorreatores baseada em exergia. Inicialmente, foi realizada uma análise dos modelos de predição de exergia química padrão comumente aplicados em estudos de análise exergética. Esta análise foi dividida em três etapas. A primeira etapa teve como objetivo realizar um levantamento bibliográfico sobre as metodologias de predição das propriedades comumente empregadas para compostos de relevância biotecnológica. Com base no levantamento bibliográfico, foi identificado a carência de metodologias específicas para estimativa de exergia química padrão, levando ao uso de métodos alternativos de cálculo. Na segunda etapa, os modelos mais promissores de predição aplicados à biocompostos foram investigados mais detalhadamente. O desempenho da predição foi avaliado para modelos baseados no método de contribuição de grupo (CG) e para uma correlação semi-empírica que considera a combustão completa do composto em questão e banco de dados empíricos. Na terceira etapa, foram propostos modelos para predição de exergia química específica para compostos orgânicos puros e macromoléculas de relevância biotecnológica. Finalmente, foi realizada a análise exergética do processo de produção de xilitol como estratégia para a tomada de decisão de condições operacionais do biorreator mais produtivas e sustentáveis. Os resultados obtidos mostraram que o método baseado em CG apresentou melhor desempenho estatístico, apresentando um ajuste de R² igual a 0,98, erro absoluto médio de 0,56 MJ/kg e erro relativo médio de 4,21%. O modelo proposto para a estimativa da propriedade apresentou valores de R² e erro relativo médio de 99,41% e 2,30%, respectivamente. Com relação à análise exergética, a metodologia proposta mostrou ser uma ferramenta útil para o desenvolvimento de sistemas fermentativos para a produção de xilitol sob o ponto de sustentabilidade. Exergy analysis is a useful tool to assess the sustainability of biotechnological processes. The application of exergetic analysis as a strategy for the study and selection of process variables is still little explored in the field of biotechnology. Knowledge of the standard chemical exergy of the compounds involved in the studied system is usually necessary for the analysis. However, the calculation of this thermodynamic property, in many cases, is not trivial, since there is still a limited number of thermodynamic data available in the literature for biocompounds. Therefore, this thesis presents a proposal for decision-making on operating conditions of bioreactors based on exergy. Initially, an analysis of the standard chemical exergy prediction models commonly applied in exergetic analysis studies was performed. This analysis was divided into three stages. The first stage aimed to carry out a bibliographical survey on the property prediction methodologies commonly used for biotechnologically relevant compounds. In the second stage, the most promising prediction models applied to biocompounds were investigated in more detail. The prediction performance was evaluated for models based on the group contribution method and for a semi-empirical correlation that considers the complete combustion of the compound in question and empirical database. In the third step, hybrid models for prediction of specific chemical exergy for pure organic compounds and macromolecules of biotechnological relevance were proposed. Finally, an exergetic analysis of the xylitol production process was carried out as a strategy for decision-making on more productive and sustainable operating conditions for the bioreactor. The results obtained showed that the GC-based method presented better statistical performance, presenting an adjustment of equal to 0.98, mean absolute error of 0.56 MJ.kg−1 and mean relative error of 4.21%. The proposed model for property estimation showed values and mean relative error of 99.41% and 2.30%, respectively. Regarding the exergetic analysis, the proposed methodology proved to be a useful tool for the development of fermentative systems for the production of xylitol from the point of sustainability.