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The presence of two metals (M1M2) in a zeolite structure enhances the degradation of pollutants in liquid or gas phase comparing to monometallic catalysts. In this work, the complete oxidation of ethyl acetate into CO2 was achieved by metal catalysts based on NaY zeolite prepared by the ion-exchange method. The metal zeolite catalysts were optimized by used several parameters: (i) the presence of a second metal in M1M2 catalysts; (ii) the presence or not of a noble metal in the pair CuM2 (M2=Pd, Zn or Ag); (iii) the order of introduction of the metals in M1M2 catalysts (CuPd or PdCu); (iv) particle size of NaY and NaYnano; and (v) the effect of simultaneously adding metal species (Cu and Pd). M1M2 catalysts presented the best results compared to the monometallic catalysts and the presence of a noble metal in M1M2 catalysts enhanced their acivity. Among the metal phases studied, the catalyst (CuPd)0.01-Y was shown to be the most efficient for this application., This work has been developed under the scope of the projects: BioTecNorte (operation NORTE-01-0145-FEDER-000004) and “AIProcMat@N2020-Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020”, NORTE-01-0145FEDER-000006, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). This work also has been funded by national funds (FCT, Fundação para a Ciência e a Tecnologia), through the projects: PTDC/AAGTEC/5269/2014, Centre of Chemistry (UID/QUI/ 00686/2013 and UID/QUI/0686/2016) and LSRE/LCM (POCI-010145-FEDER-006984)., info:eu-repo/semantics/publishedVersion

In situ single-crystal X-ray diffraction data were used to unravel the structural dynamics and enthalpy and entropy of adsorption of CO2 into Y zeolite. A principal-component-analysis- (PCA) based approach is applied in an innovative way to single-crystal X-ray diffraction data analysis, allowing one to selectively detect the information from the subset of active atoms. The potential of and limitations of PCA in single-crystal diffraction are discussed., The increasing efficiency of detectors and brightness of X-rays in both laboratory and large-scale facilities allow the collection of full single-crystal X-ray data sets within minutes. The analysis of these ‘crystallographic big data’ requires new tools and approaches. To answer these needs, the use of principal component analysis (PCA) is proposed to improve the efficiency and speed of the analysis. Potentialities and limitations of PCA were investigated using single-crystal X-ray diffraction (XRD) data collected in situ on Y zeolite, in which CO2, acting as an active species, is thermally adsorbed while cooling from 300 to 200 K. For the first time, thanks to the high sensitivity of single-crystal XRD, it was possible to determine the sites where CO2 is adsorbed, the increase in their occupancy while the temperature is decreased, and the correlated motion of active species, i.e. CO2, H2O and Na+. PCA allowed identification and elimination of problematic data sets, and better understanding of the trends of the occupancies of CO2, Na+ and water. The quality of the data allowed for the first time calculation of the enthalpy (ΔH) and entropy (ΔS) of the CO2 adsorption by applying the van ’t Hoff equation to in situ single-crystal data. The calculation of thermodynamic values was carried out by both traditional and PCA-based approaches, producing comparable results. The obtained ΔH value is significant and involves systems (CO2 and Y zeolite) with no toxicity, superb stability and chemical inertness. Such features, coupled with the absence of carbonate formation and framework inertness upon adsorption, were demonstrated for the bulk crystal by the single-crystal experiment, and suggest that the phenomenon can be easily reversed for a large number of cycles, with CO2 released on demand. The main advantages of PCA-assisted analysis reside in its speed and in the possibility of it being applied directly to raw data, possibly as an ‘online’ data-quality test during data collection, without any a priori knowledge of the crystal structure.

2,6-dimethyl naphthalane (2,6-DMN ) is an important dimethyl naphthalene (DMN) which is used in the synthesis of a new polymer polyethylene naphthalate’s (PEN) monomers 2,6-naphthalane dicarboxylic acid (2,6-NDCA). DMN’s are nine isomers and among them 2,6-DMN is the most important one. So far zeolites which have different qualities have been used for 2,6-DMN synthesis. In this work, methylation of 2 methyl naphthalene (2-MN) for synthesis of 2,6-DMN over Cu and La modified Y zeolite (CBV720, surface area=726m2/g\ SiO2/Al2O3=30), as experimental was intended for the finding of rate expression. In methylation reaction molar ratio of 1:5:5 2-MN:1,3,5 trimethyl benzene (mesitylene): methanol was fed into the reactor. For kinetic experiments, the changing of 2-MN conversion, the formation of 2,6-DMN and 2,6-DMN / 2,7-DMN ratio with different temperature, space velocity and catalyst were researched. For methylation kinetic, the rate expression depending on the 2MN and methanol concentration was determined. Arrhenius equation was used for calculation of frequency factor (ko) and activation energy (EA), 2,6-Dimetilnaftalin (2,6-DMN), yeni bir polimer olan polietilen naftalatın (PEN) monomerlerinden biri 2,6-naftalin dikarboksilik asitin (2,6-NDCA) üretiminde kullanılan önemli bir dimetilnaftalindir. Dimetil naftalinlerin dokuz adet izomeri vardır ve bunların içinde, 2,6-DMN en önemlisidir. Günümüze kadar 2,6-DMN sentezi için değişik özelliklere sahip zeolit katalizörler kullanılmıştır. Bu çalışmada, Cu ve La metalleri ile modifiye edilmiş Y zeolit (CBV720, yüzey alanı=726m2/g\ SiO2/Al2O3=30) katalizörler üzerinde 2 metil naftalinin (2-MN) metilasyonuyla 2,6-DMN sentezinde, deneysel olarak metilasyon reaksiyonu hız ifadesinin bulunması amaçlanmıştır. Metilasyon reaksiyonunda reaktöre mol oranı 1:5:5 olan 2-MN: 1,3,5-trimetilbenzen (mezitilen): metanol karışımı beslenmiştir. Kinetik deneylerinde, 2-MN dönüşümünün, 2,6-DMN oluşumunun, 2,6-DMN/2,7-DMN oranının, farklı sıcaklık, boşluk hızı ve katalizör ile değişimleri bulunmuştur. Metilasyon kinetiğinde, 2-MN ve metanol derişimine bağlı reaksiyon hız ifadesi bulunmuştur. Arrhenius denklemi yardımıyla frekans faktörü (k0) ve aktivasyon enerjisi (EA) de hesaplanmıştır.

ZSM-5 and Y zeolites were modified with iron by an ion-exchange method and then calcined at 773, 873, 973 and 1,073 K. The obtained materials were character- ized with respect to textural parameters (low-temperature N 2 sorption), structure (X-ray diffraction, UV–vis–DRS), redox properties (H 2 -temperature programmed desorption, TPD) and surface acidity (NH 3 -TPD). The obtained results have shown that the structure of zeolites influenced form, aggregation and content of the introduced iron species. In case of the FAU type structure characterized by wide pores (max. ring size, T-atoms—12) mainly iron in form of mononuclear Fe 3 ? cations and Fe x 3 ? O y oligonuclear clus- tered species was found. On the other hand for the MFI type structure characterized by smaller pores (max. ring size, T-atoms—10) significant contribution of iron in the form of bulky Fe 2 O 3 clusters located possibly on the outer surface of ZSM-5 was detected. Such significant differ- ences in distribution of iron species is probably related to various mobility of iron species in the pore systems of both zeolites. The obtained materials were tested as catalysts in the process of N 2 O decomposition. Calcination of zeolites at different temperatures influenced neit.

A complex cation, diNOsarcobalt(III), [Co(diNOsar)]3+, (diNOsar = 1,8-dinitro-3,6,10,13,16,19-hexaazabicyclo-[6.6.6]eicosane), was synthesized and immobilized in the cavities of a Y zeolite by the reaction of precursor species in the pores of the zeolite. The encapsulated material was compared to the compound diNOsarcobalt(III) chloride, [Co(diNOsar)]Cl3. Both diNOsarcobalt(III) chloride and the zeolite-encapsulated complex, [Co(diNOsar)]3+/zeolite, were obtained in high yield and characterized by ultraviolet-visible and infrared spectroscopy. X-ray diffraction demonstrated the incorporation of the complex cation into the pores of the zeolite. The catalytic production of hydrogen peroxide from oxygenated water confirmed the successful synthesis of the complex diNOsarcobalt(III) immobilized in the zeolite.

Fil: García, Juan Rafael. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Se desarrollaron prototipos de catalizadores para maximizar el rendimiento y mejorar la calidad del corte de destilados medios (LCO) en el craqueo catalítico de hidrocarburos (FCC), y mejorar el procesamiento de otras alimentaciones complejas que contengan moléculas voluminosas. Se generó mesoporosidad sobre zeolita Y (principal componente en catalizadores de FCC) mediante tratamiento con NaOH para mejorar el acceso de las moléculas voluminosas de la alimentación a los sitios catalíticos. La evaluación catalítica consistió en el craqueo de 1,3,5-tri-isopropilbenceno (reactivo modelo) y gasoil de vacío (alimentación típica de FCC). En ambos casos, la mesoporosidad mejoró la actividad y selectividades observadas hacia los productos intermedios (di-isopropilbencenos y LCO, respectivamente). En el upgrading catalítico de bio-oil (alimentación renovable, oxigenada) la mesoporosidad mejoró la desoxigenación y se obtuvieron hidrocarburos de mejor calidad. También se atenuó la acidez Brönsted de otra serie de zeolitas Y, mediante intercambios iónicos con NaNO3, con lo que se logró moderar su actividad y mejorar la selectividad a LCO y su calidad. Además, la menor acidez desfavoreció las reacciones de transferencia de hidrógeno, que conducen a la formación de aromáticos que disminuyen la calidad del LCO; esto fue corroborado en experimentos de craqueo de n-hexadecano (reactivo modelo). Finalmente, se desarrolló un modelo riguroso aplicable al análisis de reacciones consecutivas (A→B→C), que describe los procesos simultáneos de difusión, adsorción y reacción química en partículas de catalizador poroso, en un reactor discontinuo de mezcla perfecta. Las simulaciones realizadas permiten definir estrategias para maximizar la selectividad observada hacia productos intermedios de interés. In order to maximize the LCO, middle distillates cut in the catalytic cracking of hydrocarbons (FCC), yield and improve its quality as well as to improve the upgrading of other feedstocks containing bulky molecules, prototypes of FCC catalysts were developed. To improve the accessibility of bulky molecules to the active sites, mesoporosity was generated on Y zeolite (the main component of FCC catalysts) particles by means of desilication using NaOH. The catalytic performance of the various catalysts was evaluated through the cracking of 1,3,5-tri-isopropylbenzene (a model compound) and of vacuum gasoil (a typical FCC feedstock). In both cases, the mesoporosity improved the observed activities and selectivities to intermediate products (di-isopropylbenzene and LCO, respectively). In the catalytic upgrading of bio-oil (a renewable oxygenated feedstock) the mesoporosity improved the deoxygenation, the resulting hydrocarbons mixture having better quality. Moreover, in order to moderate the activity and increase the LCO’s selectivity and quality, the Brönsted acidity of another series of Y zeolites was reduced by means of ion exchange using NaNO3. Furthermore, the lesser acidity inhibited the hydrogen transfer reactions, which lead to the formation of aromatic hydrocarbons, thus decreasing the LCO’s quality. This was shown with n-hexadecane (a model compound) cracking experiments. Finally, a rigorous model, applicable to the consecutive (A→B→C) reaction analysis, which describes the simultaneous diffusion-adsorption-reaction processes in porous catalyst’s particles in a well-stirred batch reactor, was developed. The simulations performed allowed defining strategies to maximize the observed selectivity to intermediate products. Consejo Nacional de Investigaciones Científicas y Técnicas Agencia Nacional de Promoción Científica y Tecnológica Universidad Nacional del Litoral

A novel utilization method of filter residue from the preparation process of zeolite-based catalysts was investigated. Y zeolite and a fluid catalytic cracking (FCC) catalyst were synthesized from filter residue. Compared to the Y zeolite synthesized by the conventional method, the Y zeolite synthesized from filter residue exhibited better thermal stability. The catalyst possessed wide-pore distribution. In addition, the pore volume, specific surface area, attrition resistance were superior to those of the reference catalyst. The yields of gasoline and light oil increased by 1.93 and 1.48 %, respectively. At the same time, the coke yield decreased by 0.41 %. The catalyst exhibited better gasoline and coke selectivity. The quality of the cracked gasoline had been improved., Proučena je upotreba taloga preostalog nakon priprave katalizatora baziranog na zeolitima. Od taloga su pripravljeni zeolit Y i katalizator za katalitičko krekiranje u fluidiziranom sloju (FCC). Ovako sintetiziran zeolit Y termički je stabilniji u odnosu na zeolit Y sintetiziran konvencionalnom metodom. Katalizator ima široku distribuciju veličine pora. U odnosu na referentni katalizator pokazuje veći obujam pora i specifičnu površinu te bolju otpornost na atriciju. Iskorištenje benzina i lakog ulja povećalo se za 1,93 i 1,48 %, a koksa smanjilo za 0,41 %. Katalizator je pokazao bolju selektivnost s obzirom na benzin i koks, a poboljšala se kvaliteta krekiranog benzina.

Polietilen tereftalat (PET)’a alternatif ve özellikleri PET’den daha iyi olan polietilen naftalat (PEN)’in üretiminde 2,6-Dimetil naftalin (2,6-DMN) önemli bir birleşiktir. 2,6-DMN, PEN’in monomerlerinden birisi olan 2,6-naftalindikarboksilik asitin ( 2,6-NDCA) sentezinde ana girdi maddesidir (Zhang 2010). 2,6-DMN üretimi bir çok araştırmacı tarafından çalışılmıştır (Lin 2006). 2,6-DMN üretiminde en önemli sorun, yüksek seçimlilikte ve yüksek dönüşümde ürün veren katalizör geliştirilmesidir. Bu çalışmada, Y zeolit katalizörü üzerinde 2-metil naftalinin (2-MN) disproporsiyonu ile dimetil naftalinlerin üretimi araştırılmıştır. Deneylerde besleme olarak molar bileşimi 1:1 olan 2-MN:Benzen karışımı kullanılmıştır. Reaktöre 2cm3 katalizör yerleştirilmiş ve bu katalizör azot ortamında aktivasyon ve test işlemine tabi tutulmuştur. Elde edilen gaz ürünler, soğuk etilen glikol sirküle edilen bir yoğuşturucu ile yoğunlaştırılmıştır. Yoğuşturucuda toplanan sıvı ürünler 60 metre uzunluğa sahip kapiler kolonlu GC-MS ile analiz edilmiştir., 2,6-dimethyl naphthalene (2,6-DMN) is an important compound for polyethylene naphthalate (PEN) production which is an alternative for polyethylene teraphtalate (PET) and has better qualities than PET. 2,6-DMN is a precursor for 2,6-naphthalenedicarboxylic acid (2,6-NDCA) synthesis which is one of the monomers of PEN (Zhang 2010). Synthesis of 2,6-DMN have been studied by many workers (Lin 2006). In the production of 2,6-DMN, the most important problem is to develop catalysts giving products with high selectivity and high conversion. In this study, the production of dimethyl naphthalene via disproportionation of 2-methyl naphthalene (2-MN) over Y zeolite catalyst was investigated. In the experiments a solution which’s molar composition was 1:1 2-MN:benzene was used. 2 cm3 of catalysts were placed in the reactor and this catalysts were activated and tested under nitrogen medium. In exit of the reactor, obtianed gas products were condensed with a condenser circulating cold ethylene glycol. Liquid products obtained in condenser were analysed with GC-MS which has 60 meter capilar column

Y zeolite was desilicated by means of alkaline treatments (NaOH 0.05, 0.10 and 0.20 M) during 15 min to produce varying mesoporosity over it. Catalysts were made with a SiO2 matrix and a binder. Pine sawdust bio-oil was produced by pyrolysis and immediately upgraded on a bed of the compound catalysts. The experiments were produced in a fixed bed reactor at 550 ºC using different catalyst to reactants relationships. The desilicated zeolites were more effective than the parent zeolite to deoxygenate bio-oil and produce more hydrocarbons, with higher selectivity to olefins (more than 35 %wt.) and lower selectivity to aromatics (less than 60 %wt.) in gasoline. The selectivity to C4- and gasoline olefins increased if the mesoporosity was higher, and the coke formed was less condensed. These observations were the result of improvements in the diffusion of bulky molecules in bio-oils, such as phenolic ethers, increasing their conversion to hydrocarbons. Fil: García, Juan Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Bertero, Melisa Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Falco, Marisa Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

In this work the preparation, characterization and performance of Y-zeolite as catalyst for electro-Fenton treatment of pesticides was carried out. Initially iron supported Y-zeolite (Fe-Y) was prepared and evaluated for the degradation of imidacloprid and chlorpyrifos. Kinetics studies determined that the pesticides removal followed a pseudo-first-order kinetic model. However, the reusability of this catalyst was not appropriated and to enhance its recyclability, Fe-Y catalyst was embedded in alginate (Al-Fe-Y). The new catalyst showed similar degradation efficiency; and the recyclability was improved. This study demonstrated that Al-Fe-Y could be efficiently used to remove commonly pesticides, imidacloprid and chlorpyrifos, of aqueous medium., This work has been supported by the Xunta de Galicia (EM2012/083). The authors are thankful to the Ramón y Cajal programme for Marta Pazos’ financial support and to C.A.C.T.I. from Vigo University for providing access to their Electron Microscopy Service.

Decalin, a naphthenic bicyclic compound, was reacted over a commercial FCC catalyst in its fresh, equilibrium and three dealuminated forms in order to analyze the formation of aromatic hydrocarbons in the gasoline and LCO cuts, heavy and light ends, respectively. A batch, fluidized bed CREC Riser simulator laboratory reactor was used at 450 ºC with short contact times from 1 to 8 s. The dealuminated catalysts showed an activity intermediate between those of the fresh and equilibrium catalysts, which can be correlated to zeolite content and acidity. Also those properties, at least in the range of values observed in this work, seem to be the most important characteristic in controlling the selectivity of the set of reactions. A reaction network was described, where hydrogen transfer reactions are considered to be the most important to form aromatics, a fact which is essentially unavoidable when a bicyclic naphthenic is converted on these catalysts. Aromatic belonged mainly to the gasoline boiling point range and, to a lower extent, to LCO. Fil: Pujro Tarquino, Richard Alfonzo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Falco, Marisa Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

Sulfur dioxide adsorptive properties of Y zeolite, the structure of which was confirmed by XRD, were investigated at temperatures within the 25?200 ?C range and sulfur dioxide concentrations between 0.9 to 6%(vol./vol). It was found that this sorbent possesses a relatively high adsorption capacity. The Y zeolite did not lose its activity during 20 adsorption desorption-regeneration cycles. The manner in which sulfur dioxide is adsorbed on Y type zeolite was also investigated by analyzing the sample with and without adsorbed SO2, using IR spectroscopy, as well as total and Lewis acidity measurements. The sulfur dioxide molecule is probably adsorbed by hydrogen bonding to one or two conveniently positioned surface hydroxyl groups.

A technique for the quantitative determination of adsorbed species on zeolites and other solids was designed by coupling infrared spectroscopy and in situ thermogravimetry. The weight of H-Y zeolites in an infrared spectrometer was monitored upon pyridine adsorption by a McBain type microbalance. Improved extinction coefficients for the pyridinium band and for ν(OH) bands were determined on these reference materials. The influence of the temperature used for desorption of physisorbed pyridine was studied.

Fil: Pujro Tarquino, Richard Alfonzo. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Se evaluó la reactividad de compuestos modelo representativos de alimentaciones tradicionales y residuales utilizadas en el proceso de FCC (Fluid Catalytic Cracking) sobre catalizadores sintetizados en planta piloto, comercial de maximización de LCO (Light Cycle Oil) fresco y equilibrado, y modificados en laboratorio por steaming (tratamiento hidrotérmico con vapor, 788 ºC, distintos tiempos de contacto). La evaluación catalítica se realizó en un reactor Simulador de Riser CREC a distintas temperaturas, relaciones Cat/Oil y tiempos de reacción. La identificación de los productos de reacción fue por cromatografía gaseosa. La conversión de compuestos presentes en los cortes gasolina y LCO, como decalina (nafténico), tetralina (nafténico-aromático) y naftaleno (aromático), permitió identificar los aromáticos formados y proponer mecanismos de formación de tales compuestos. La reactividad de poliaromáticos presentes en el LCO y HCO (Heavy Cycle Oil), como el 1-feniloctano y bifenil (aromáticos alquilados), el fluoreno y 9, 10 dihidrofenantreno (nafténico-aromáticos) y el fenantreno, pireno y benzo(a)antraceno (aromáticos policíclicos) permitió reconocer que estos compuestos pueden fraccionarse y condensarse, favoreciendo la formación de benceno y coque respectivamente. La conversión de quinolina-65, considerado como reactivo representativo de residuos mostró alta sensibilidad a la producción de coque, lo que permitiría su empleo como compuesto modelo para determinar selectividades a coque. La reactividad de las fracciones constituyentes de un residuo de torre atmosférica (saturados, aromáticos, resinas y asfaltenos), sugiere que cada fracción tiene un comportamiento individual diferente, existiendo interacciones entre las mismas cuando integran un residuo, por lo que su comportamiento global no puede predecirse de manera aditiva. The reactivity of model compounds representing conventional and residual feedstocks in the Fluid Catalytic Cracking (FCC) process was studied over catalysts which were synthetized in pilot plant, equilibrium and fresh commercial aimed at maximizing Light Cycle Oil (LCO) and laboratory modified (hydrothermal treatment with steam, 788 ºC, various contact times). The catalytic evaluation was performed in a CREC Riser Simulator reactor at different temperatures, Cat/Oil relationships and reaction times. Product identification was performed by means of gas chromatography. The conversion of compounds which are present in gasoline and LCO, such as decalin (naphthenic), tetralin (naphthenic-aromatic) and naphthalene (aromatic) allowed to identify the aromatic compounds formed and propose mechanisms to explain their formation. The reactivity of polyaromatic compounds present in LCO and Heavy Cycle Oil (HCO), such as 1-phenyloctane and biphenyl (alkylated aromatics), fluorene and 9,10-dihydrophenanthrene (naphthenic-aromatics) and phenanthrene, pyrene and benz[a]anthracene (polycyclic aromatics) confirmed that these compounds can be cracked and condensed, leading to benzene and coke, respectively. The conversión of quinolin-65, assumed as representative of residual feedstocks, showed a high sensitivity to coke yield, thus suggesting that it is possible to use it as a model compound to study coke selectivities. The reactivities of the various fractions which make up an atmospheric tower bottom stream (saturates, aromatics, resins and asphalthenes) suggest that each fraction has a particular behaviour, interactions between them existing when they form a resid; in this way, the overall behaviour can not be predicted following an additive approach. Consejo Nacional de Investigaciones Científicas y Técnicas Universidad Nacional del Litoral Agencia Nacional de Promoción Científica y Tecnológica

The performance of two zeolites with different structures and acidity properties was evaluated on the biosorption of Cr(VI) and catalytic oxidation of ethyl acetate. The starting zeolites, HY and HZSM5, were modified by ion exchange treatments in order to obtain zeolites with different acidity and sodium content. Arthrobacter viscosus supported on the different zeolites was used for Cr(VI) recovery from solution. The best removal efficiencies and uptake of chromium were achieved for the Y zeolites due to their higher ion exchange capacity. The Y and ZSM5 zeolites were characterized by ICP-AES, SEM, NH3 chemisorption, XRD and N2 adsorption. Y and ZSM5 zeolites obtained after biosorption of chromium were successfully reused as catalysts in the oxidation of ethyl acetate. The chromium-loaded ZSM5 zeolites were considerably more active and selective towards CO2 than chromium-loaded Y zeolites, essentially due to its different framework structure, textural and acidity properties.

Cis- and trans-decalin were reacted over cracking catalysts to study the formation of aromatics in a particular fraction of the liquid products obtained in the fluid catalytic cracking process (FCC). A batch, fluidized bed CREC riser simulator reactor was used at 673 and 723 K and contact times varied from 3 to 15 s. Cis-decalin was much more reactive. Despite differences induced and measured in their accessibility indices, the catalysts led to similar activity profiles, suggesting that diffusion restrictions do not prevail. Products were C 1 -C 12 hydrocarbons while coke was very low. Isomerization, cracking, hydrogen transfer, ring opening, ring contraction and alkylation reactions occurred and products from the various reactions were observed at very short reaction times. Bicyclic C 10 naphthenics and alkyl-substituted C 7 -C 11 aromatics or naphtheno-aromatics were the most important products. A reaction mechanism with three initial routes (isomerization, ring opening and direct hydrogen transfer reactions) was proposed. Fil: Pujro Tarquino, Richard Alfonzo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Falco, Marisa Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Pedrosa, Anne M. Garrido. Universidade Federal de Sergipe; Brasil Fil: Souza, Marcelo J. B.. Universidade Federal de Sergipe; Brasil Fil: Morgado Jr., Edisson. Petrobras; Brasil Fil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The aim of this work was the evaluation of the performance of two zeolites with different structures (FAU and MFI) and acidity properties in the biosorption of Cr(VI) and catalytic oxidation of ethyl acetate. The starting zeolites, Y (FAU) and ZSM5 (MFI), were modified by ion exchange treatments with NaNO3 in order to obtain zeolites with different acidity and sodium content. A biosorption system consisting of a bacterium, Arthrobacter viscosus, supported on the different zeolites was used for Cr(VI) reduction and removal from solution. The best removal efficiencies and uptake of chromium, above 90% and 14 mgCr/gzeolite respectively, were achieved for Y zeolites due to their higher ion exchange capacity in comparison with ZSM5 zeolites. The ion exchange treatment did not produce considerable changes on the uptake process performed by the modified zeolites. Y and ZSM5 zeolites were characterized by ICP-AES, SEM, NH3 chemisorption, XRD and N2 adsorption. Y and ZSM5 zeolites obtained after biosorption presented chromium loadings between 0.92 and 1.20%, and were successfully reused as catalysts in the oxidation of ethyl acetate. The chromium-loaded ZSM5 zeolites were considerably more active and selective towards CO2 than chromium-loaded Y zeolites, essentially due to their different framework structure, textural and acidity properties. The different sodium content of Y and ZSM5 zeolites did not produce marked changes in the catalytic behaviour of these catalysts., B. Silva, H. Figueiredo and O.S.G.P. Soares thank FCT-Portugal (Fundacao para a Ciencia e Tecnologia) for the concession of their PhD grants. A.E. Lewandowska thanks the Spanish Ministry of Science and Innovation for a "Juan de la Cierva" postdoctoral position. This work was partially funded by the Centre of Biological Engineering and Centre of Chemistry (University of Minho, Portugal) through a POCTI project (ref: POCTI-SFA-3-686), by the Spanish Ministry of Science and Innovation (CTQ2008-04261/PPQ) and by FCT and FEDER under Programs POCI 2010 and COMPETE, Project PTDC/AMB/69065/2006.

Platinum catalysts supported on zeolite KY (Si/Al = 12.7), modified with magnesium, calcium or barium, were evaluated in n-octane reforming to produce ethylbenzene. The catalysts were characterized by nitrogen adsorption, 27Al and 29Si solid state nuclear magnetic resonance, Fourier transform infrared spectroscopy using carbon monoxide or pyridine, metal dispersion measurements and programmed temperature oxidation. No significant structural change was noted for the solids due to the dopants exceptfor barium, which decreased the specific surface area, due to the partial blockage of the zeolite channels by the large size ions. However, a decrease was noted for all samples due to platinum, which partially blocked the zeolite channels. Barium also decreased the crystallinity while platinum caused this effect only for calcium and barium-containing samples, due to the structure partial collapse. Metallic platinum species in several electronic states were detected in the cages of zeolite, barium-containing catalyst showing the most electron-enriched platinum atoms. The amount of Lewis and Brønsted acid sites increased due to magnesium and calcium but barium increased only the amount of Lewis acid sites, as compared to potassium-containing solid. The catalysts with magnesium and barium showed the same platinum dispersion, which was higher than the one containing calcium. All catalysts were active in n-octane reforming at 723K and selective to ethylbenzene, but the conversion dropped with time reaction due to the decrease of specific surface area and to coke deposition. The calcium-containing sample produced the hardest coke, which led to the highest drop in conversion. The n-octane conversion was supposed to occur by a monofunctional mechanism but the bifunctional mechanism also seemed to occur due to the residual acidity of the catalysts. The calcium and barium-containing catalysts were the most selective toethylbenzene, due to electron-enriched platinum species related to promoters, but the low ethylbenzene selectivity for the magnesium-containing catalyst was compensated by its high conversion, resulting in similar yields for all catalysts. Fil: Fonseca, Juliana Da Silva Lima. Universidade Federal da Bahia; Brasil Fil: Júnior, Arnaldo Da Costa Faro. Universidade Federal do Rio de Janeiro; Brasil Fil: Grau, Javier Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Rangel, Maria do Carmo. Universidade Federal da Bahia; Brasil

Acesso restrito: Texto completo. p. 201-210. Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2012-04-12T19:15:09Z No. of bitstreams: 1 __ac.els-cdn.com_S092686...5b817406ba7e2590b7db336478a27.pdf: 688197 bytes, checksum: ef2559e860bf5c3d412902fc50623d26 (MD5) Made available in DSpace on 2012-04-12T19:15:09Z (GMT). No. of bitstreams: 1 __ac.els-cdn.com_S092686...5b817406ba7e2590b7db336478a27.pdf: 688197 bytes, checksum: ef2559e860bf5c3d412902fc50623d26 (MD5) Previous issue date: 2010 Platinum catalysts supported on zeolite KY (Si/Al = 12.7), modified with magnesium, calcium or barium,were evaluated in n-octane reforming to produce ethylbenzene. The catalysts were characterized by nitrogen adsorption, 27Al and 29Si solid state nuclear magnetic resonance, Fourier transform infrared spectroscopy using carbon monoxide or pyridine, metal dispersion measurements and programmed temperature oxidation. No significant structural change was noted for the solids due to the dopants except for barium, which decreased the specific surface area, due to the partial blockage of the zeolite channels by the large size ions. However, a decrease was noted for all samples due to platinum, which partially blocked the zeolite channels. Barium also decreased the crystallinity while platinum caused this effect only for calcium and barium-containing samples, due to the structure partial collapse. Metallic platinum species in several electronic states were detected in the cages of zeolite, barium-containing catalyst showing the most electron-enriched platinum atoms. The amount of Lewis and Brønsted acid sites increased due to magnesium and calcium but barium increased only the amount of Lewis acid sites, as compared to potassium-containing solid. The catalysts with magnesium and barium showed the same platinum dispersion, which was higher than the one containing calcium. All catalysts were active in n-octane reforming at 723K and selective to ethylbenzene, but the conversion dropped with time reaction due to the decrease of specific surface area and to coke deposition. The calcium-containing sample produced the hardest coke, which led to the highest drop in conversion. The n-octane conversion was supposed to occur by a monofunctional mechanism but the bifunctional mechanism also seemed to occur due to the residual acidity of the catalysts. The calcium and barium-containing catalysts were the most selective to ethylbenzene, due to electron-enriched platinum species related to promoters, but the low ethylbenzene selectivity for the magnesium-containing catalyst was compensated by its high conversion, resulting in similar yields for all catalysts.

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2019-07-29T19:12:20Z No. of bitstreams: 1 JAILSON ARRUDA DE ARAÚJO – DISSERTAÇÃO (PPGEQ) 2008.pdf: 3209291 bytes, checksum: 2201ac8fa74cd242ad45ab718d0678c9 (MD5) Made available in DSpace on 2019-07-29T19:12:21Z (GMT). No. of bitstreams: 1 JAILSON ARRUDA DE ARAÚJO – DISSERTAÇÃO (PPGEQ) 2008.pdf: 3209291 bytes, checksum: 2201ac8fa74cd242ad45ab718d0678c9 (MD5) Previous issue date: 2008-09-29 Capes A crescente demanda por destilados leves, juntamente com as rigorosas especificações impostas a fim de minimizar os impactos ambientais provocados por combustíveis automotivos, tem feito crescer a importância dos processos de hidrocraqueamento e hidrotratamento nas modernas refinarias. Hidrocraqueamento é o método mais eficiente para produção de frações leves a partir de óleos pesados. Em uma refinaria, esta tecnologia tem sido aplicada para produzir gasolina de alta qualidade, combustível para aviação, gasóleo e lubrificantes. A maioria dos catalisadores convencionais para o hidrocraqueamento é bifuncional. Possui função hidrogenante e desidrogenante assim como também função ácida. Neste trabalho os experimentos de hidrocraqueamento foram realizados num reator de leito fixo sob alta pressão e temperatura. O esquema experimental consistiu em quatro partes principais: bomba de alimentação, vaporizador, reator e unidade para análise dos gases. Neste estudo, foram preparados catalisadores NiMo suportados em zeólita HY obtida a partir da NaY. Os catalisadores foram caracterizados por meio de diferentes técnicas, e suas propriedades catalíticas em relação à atividade, seletividade ao hidrocraqueamento e rendimentos aos produtos craqueados foram também examinados. As propriedades físicas dos catalisadores foram determinadas por meio de adsorção física de N2 e difração de raios-X. Como caracterização semi-quantitativa dos metais impregnados utilizou-se a espectroscopia de raios-X por energia dispersiva-EDX. As reações de hidrocraqueamento do cumeno foram realizadas com e sem sulfetos metálicos de níquel e molibdênio. Foi utilizado o método de impregnação sem excesso de solução, para tanto foram preparadas soluções de heptamolibdato de amônio e nitrato de níquel. Após impregnação, os catalisadores passaram por secagem e calcinações. Em todos os catalisadores avaliados, a presença de sulfetos metálicos melhorou a atividade catalítica. Mesmo com a baixa área superficial dos catalisadores preparados, o efeito provocado pela impregnação de níquel e molibdênio sobre os suportes foi bastante positivo, uma vez que todos apresentaram conversões muito significativas e comparáveis com o utilizado comercialmente. Verificou-se que o papel dos sulfetos de NiMo foi de fornecer íons hidrogênio ativos para os sítios da zeólita. O hidrocraqueamento do cumeno sobre catalisadores sulfetados indicou que a fase metálica suportada contribuiu de forma significativa nas características de craqueamento dos catalisadores. The growing demand for middle distillates, together with rigorous specifications directed toward minimizing the environmental impact of automotive fuels, has increased the importance of hydrocracking and hydrotreating processes in modern refineries. Hydrocracking is the most efficient method for producing light fractions from heavy oil. In petroleum refining, this technology has been carried out to produce high quality gasoline, jet fuel, gas oil and lubricants. Most of the conventional hydrocracking catalysts are dual functional catalysts. They have a hydrogenation-dehydrogenation function as well as an acidic function. In this study the hydrocracking experiment was conducted in a high pressure fixed bed reactor and under high temperature. The scheme consisted of four main parts: feeder pump, vaporizer, reactor and a gas analysis unit. In this study, it was prepared NiMosupported zeolite catalysts using HY which was obtained from NaY. The catalysts were characterized with different techniques, and their catalytic properties with respect to the activity, selectivity to hydrocracking and yield of the cracked products were also examined. The physical properties of the catalysts were measured by N2 adsorption and X-ray diffraction (XRD). It was also used energy dispersive X-ray spectrometry – EDX for semi-quantitative characterization of the metals impregnated. Cumene hydrocracking reactions were carried out over zeolite with and without NiMo sulfide. The loading of NiMo was performed by the incipient wetness method using aqueous solutions of ammonium heptamolybdate and nickel nitrate. After impregnation, the catalysts were dried followed by calcinations. In all cases, the loading of NiMo sulfide enhanced catalytic activity. Even so the surface area of the catalysts was very low, the effect of impregnating nickel and molybdenum on the supports was strongly positive, since they all presented significant conversion comparable to the commercial one. The role of NiMo sulfide was found to supply active hydrogen to the hydrocracking active sites on zeolite. Cumene hydrocracking on the sulfided catalysts indicated the supported molybdenum and nickel phase contributed significantly to the cracking functionality of the catalysts

International audience; Transient diffuse reflectance UV–vis absorption (TDRUV) and time resolved resonance Raman (TR3) spectroscopy (370 nm exciting laser line, 8 ns) were performed to investigate the species generated by UV pulsed laser photolysis (248 nm, 20 ns) of biphenyl (BP) occluded in cavities of dehydrated silica-rich Y-faujasitic (MnFAU) zeolites with Mn(AlO2)n(SiO2)192−n formulae per unit cell. The TDRUV spectra were recorded in the time range 0.5–340 μs and the TR3 spectra were recorded in the 0.05–100 μs as functions of aluminum content (n = 0, 56), extra framework cations (M = Na+, K+, Cs+), BP loading (1, 2, 4, 8, 16 BP/UC) and laser energy (0.15–1.5 mJ). Specific spectra of BP(T1) triplet state, BP•+ radical cation, trapped electron as Na43+ cluster and BP•− radical anion were resolved by Multivariate curve resolution (MCR) of TDRUV and TR3 data sets. The RR spectra of BP•+ and BP(T1) correspond to nearly planar structures. The concentration decays fit a model of dispersed heterogeneous kinetics. At lower laser energy, BP(T1) was generated as major transient species. The energy transfer via T1 occurs with rates not greater than 10−6 s−1. Photoionization is found to be the dominant phenomenon at higher pump laser energy. BP•+, Na43+ and BP•− exhibit distinct decay behaviors with rates not lower than 10−3 s−1. In polar environment of Na56FAU supercage, the ejected electron is trapped as Na43+ cluster at low loading and as BP•− at high loading. In the non-polar environment of FAU supercage, the ejected electron is captured by BP(S0) even at low loading. The effects of Si/Al ratio, extraframework cation and BP loading upon the energy and electron transfer rates were discussed according to BP photochemical behavior in solvents.

Thermogravimetric (TGA) and differential scanning calorimetric (DSC) analyses were used to investigate the effect of the acidity behaviour of Y zeolites on the catalytic degradation of polyethylene (PE). The acidity behaviour of these zeolites was modified by ion exchange treatments. Two Y zeolites with similar Si/Al atomic ratios were subjected to an ion exchange treatment using NaNO 3 for H-form (HY) and NH 4 NO 3 for Na-form (NaY). The activity and the deactivation behaviour of the Y zeolites were determined in the samples by TGA measurements, using a polymer/catalyst ratio of 9:1. The sample residues obtained after an isothermic TGA, were analysed by DSC, in order to evaluate the crystallinity of each mixture. The HY zeolite, which has the strongest acidity, reduced the onset temperature resulting in more rapid degradation of the polymer. It is shown that the ion exchange treatment over Y zeolites enhances the selective catalytic degradation of polymer in detriment of the rapid deactivation.

The conversion of cyclohexene over different commercial FCC catalysts in a batch fluidized-bed reactor under very short contact times at 300°C, was described by means of a simple lumped kinetic model that accounted for the observed yield patterns. The main branch of reaction starting from the adsorption of cyclohexene was used to assess an index based on kinetic parameters that defines the relative significance of hydrogen transfer reactions in a set that also includes proton transfer and cracking reactions. Complementary experiments with pulses of reactant on a fixed-bed reactor allowed to establish the best temperature to obtain maximum sensitivity to hydrogen transfer. The same evolutions were observed for the relationships between the index of hydrogen transfer and the paired acid site density with the Y zeolite unit cell size, confirming that two regions can be defined separated by unit cell sizes of about 24.28–24.30 Å, the correlations being stronger at low values of this parameter. Fil: de la Puente, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Sedran, Ulises Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina

Submitted by Isabel Melo (imelo@sa.isel.pt) on 2020-06-15T13:20:21Z No. of bitstreams: 1 Activity-acitity relationship_CCosta.pdf: 496763 bytes, checksum: 9f9a276ba95ec0f7968cefca8f390ba2 (MD5) Made available in DSpace on 2020-06-15T13:20:21Z (GMT). No. of bitstreams: 1 Activity-acitity relationship_CCosta.pdf: 496763 bytes, checksum: 9f9a276ba95ec0f7968cefca8f390ba2 (MD5) Previous issue date: 1999-07-22 info:eu-repo/semantics/publishedVersion

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2,4,6-Triphenylpyrylium ions entrapped inside the supercages of Y zeolite exert a remarkable catalytic effect toward the electrochemical oxidation of dopamine and norepinephrine (neurotrasmitter catecholamines) in neutral aqueous media. Domenech Carbo, Antonio, Antonio.Domenech@uv.es