Browsing by Author "Beltramone, Andrea Raquel"

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    Activated carbons synthetized from orange peel to produce clean energy
    (2022) Rivoira, Lorena Paola; Gómez Costa, Marcos Bruno; Ledesma, Brenda Cecilia; Beltramone, Andrea Raquel
    As we all know, a clean energy revolution is taking place all over the world in pursuit of replacing oil. The present work stands out an environmental point of view by proposing biomass wastes from different industrial areas to produce not only a biofuel but also as raw material to synthetize the catalyst involved in the HDO reaction. In this way the process ceases to rely on the antiquated and obsolete linear economy where products, services, wastes, materials, water and energy have a beginning and an end to become a process with greater tendency to the modern circular economy, closely related to the idea of sustainability. Products, materials and resources are expected to last as long as possible while minimizing waste as much as possible too. Agricultural and forestry waste are available everywhere being a low cost raw material and it is possible to provide added value to the organic wastes of small and medium size enterprises. The hydrodeoxygenation (HDO) of guaiacol has been performed in a batch reactor under 12 atm of H2 and different temperatures over activated carbon synthetized from orange peel discarded from juice industry. Carbon activation was carried out through a chemical process with phosphoric acid as an activating agent, varying the acid concentration, the ratio substrate/activating agent and time of contact between them. The best support was obtained using carbonization time of 1 h, temperature of carbonization of 470oC, phosphoric acid concentration of 50 wt.% and with BET area of 1429 m2/g. Subsequently, the metallic nanoparticles were deposited in the activated carbon to use the solid as a catalytic material for the hydrodeoxygenation of guaiacol. The catalytic material was modified with metallic nanoparticles of Pt. The catalysts were characterized by means of X-ray diffraction, N2 isotherms, XPS, SEM and TEM. Good structure, narrow pore size distribution and high platinum dispersion were achieved in the synthesized catalysts. The objective of this investigation is the evaluation of the catalytic activity and to compare it with SBA-15 support studied previously. The catalyst presented excellent performance for biofuels generation.
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    Aniline adsorption and polymerization over gallium modified mesoporous material.
    (Univesidsad Tecnológica Nacional., 2018) Martínez , María Laura; Rivoira , Lorena Paola; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Rivoira , Lorena Paola
    In this work we study aniline polymerization over a mesoporous Ga-SBA-3 synthesized in our laboratory. In order to modify the intrinsic acidity of the mesoporous material gallium was incorporated into the structure by post synthesis wet impregnation method using gallium nitrate. Structural and textural characterization of the materials was performed by X-ray diffraction (XRD), ICP and EDX analysis, N2 adsorption-desorption and BET area analysis, FTIR and scanning electron microscopy (SEM). The catalytic material presented a ratio Si/Ga=32. Aniline is a weak organic base and an amphiprotic compound, so it can accept or donate protons. The polyaniline (PANI) exists in diverse ways presenting different chemical and physical properties. The protonated polyaniline feature the conductivity of a semiconductor material, over 100 S/cm. Toward achieve aniline adsorption, the solid gallium silicate was exposed to aniline vapours. The aniline adsorption was studied by infrared spectroscopy and the results obtained were evaluated so as to been able to polymerize it over the mesoporous material generating a unique polyaniline-host composite with new properties. Those polyaniline/hosts composites obtained by a polymerization in-situ technique were characterized by infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. Comparing to previous results FTIR analysis of the polyaniline/Ga SBA-3 composite (PANI/Ga-SBA-3) showed characteristics bands attributed to the quinoidal stretching (N=Q=N) and C-C stretching of the benzene ring. The low angle XRD analysis showed that the mesoporous structure was maintained in spite of the gallium incorporation. The absence of PANI peaks and G2O3 in the wide angle XRD pattern confirms that the polyaniline is adsorbed over the gallium silicate mesoporous surface and the gallium is well dispersed over the support.
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    Biomass wastes as a raw material for mesoporous catalyst applied in HDO of guaiacol
    (2022) Rivoira, Lorena Paola; Ledesma, Brenda Cecilia; Gómez Costa, Marcos Bruno; Beltramone, Andrea Raquel
    As we all know, a clean energy revolution is taking place all over the world in pursuit of replacing oil. The present work stands out an environmental point of view by proposing biomass wastes different industrial areas to produce not only a biofuel but also as raw material to synthetize the catalyst involved in the HDO reaction. In this way the process ceases to rely on the antiquated and obsolete linear economy where products, services, wastes, materials, water and energy have a beginning and an end to become a process with greater tendency to the modern circular economy, closely related to the idea of sustainability. Products, materials and resources are expected to last as long as possible while minimizing waste as much as possible too. Agricultural and forestry waste are available everywhere being a low cost raw material and it is possible to provide added value to the organic wastes of small and medium size enterprises. The hydrodeoxygenation (HDO) of guaiacol has been performed in a batch reactor under 12 atm of H2 and different temperatures over activated carbon synthetized orange peel discarded juice industry. Carbon activation was carried out through a chemical process with phosphoric acid as an activating agent, varying the acid concentration, the ratio substrate/activating agent and time of contact between them. The best support was obtained using carbonization time of 1 h, temperature of carbonization of 470oC, phosphoric acid concentration of 50 wt.% and with BET area of 1429 m2/g. Subsequently, the metallic nanoparticles were deposited in the activated carbon to use the solid as a catalytic material for the hydrodeoxygenation of guaiacol. The catalytic material was modified with metallic nanoparticles of Pt. The catalysts were characterized by means of X-ray diffraction, N2 isotherms, XPS, SEM and TEM. Good structure, narrow pore size distribution and high platinum dispersion were achieved in the synthesized catalysts. The objective of this investigation is the evaluation of the catalytic activity and to compare it with SBA-15 support studied previously. The catalyst presented excellent performance for biofuels generation.
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    Desulfuración oxidativa utilizando material mesoporoso Ti-SBA-16
    (2014) Rivoira, Lorena Paola; Vallés, Verónica; Ledesma, Brenda; Martínez, María Laura; Anunziata, Oscar Alfredo; Beltramone, Andrea Raquel
    La oxidación de compuestos organosulfurados conduce a la formación de los sulfóxidos/sulfonas correspondientes, lo que permite que sean fácilmente removidos mediante extracción en solventes polares o por adsorción. El proceso de ODS es llevado a cabo bajo condiciones muy suaves, comparado con el proceso convencional de HDS. El objetivo del presente trabajo es estudiar el efecto del método de preparación de SBA-16 modificada con titanio en el rendimiento de la ODS del DBT con H2O2 y acetonitrilo como solvente en condiciones suaves de reacción. Se estudiaron dos materiales TiO2-SBA-16 obtenido por impregnación húmeda y Ti-SBA-16 obtenido mediante síntesis directa. con una relación de Si/Ti=20. Para la actividad catalítica se lleva a cabo la reacción de oxidación a 70°C y presión atmosférica se utilizó un reactor batch. Se utilizó H2O2 como agente oxidante y acetonitrilo como solvente.
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    Direct Synthesis of ordered mesoporous carbon as support of Ir-Catalyst and its application in hydrodenitrogenation of indole.
    (Univesidsad Tecnológica Nacional., 2018) Ledesma, Brenda Cecilia; Juárez , Juliana María; Beltramone, Andrea Raquel; Juárez , Juliana María
    An ordered mesoporous carbon (OMC) modified with titania was prepared using a novel and shorter synthesis method. OMC was successfully synthesized by the carbonization of the silica/TEOT/triblock copolymer/sucrose composite in the presence of sulfuric acid. This novel material was modified with the incorporation of nanoparticles of Iridium. Structural and textural characterization of the catalyst was performed by means of N2 adsorption, XRD, UV–Vis–DRS, Raman spectroscopy, XPS, TEM and H2 Chemisorption. The characterization results indicated that the textural and structural properties of the support synthesized by the short time method are comparable with the properties of the support prepared by the hard template method. Ir-Ti-OMC catalyst obtained by short time synthesis was active and selective in the hydrogenation of indole. Main advantage of the present study is the reduction of time and cost in the synthesis of the new material and the applicability for HDT reactions.
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    Eliminación de azufre mediante desulfuración oxidativa con SBA-16 modificada con titanio
    (2014) Rivoira, Lorena Paola; Vallés, Verónica; Ledesma, Brenda; Martínez, María Laura; Anunziata, Oscar Alfredo; Beltramone, Andrea Raquel
    La oxidación de compuestos organosulfurados conduce a la formación de los sulfóxidos/sulfonas correspondientes, los cuales son mucho más polares, lo que permite que sean fácilmente removidos mediante extracción en solventes polares o por adsorción. El proceso de ODS es llevado a cabo bajo condiciones muy suaves (presión atmosférica y 60-90ºC), comparado con el proceso convencional de HDS, donde comúnmente son usadas presiones mayores a los 30 bar y temperaturas desde los 300 a los 380ºC. Resultados recientes muestran que tamices moleculares que contienen Ti exhiben buena reactividad catalítica en la oxidación de sulfuro, mercaptano, tiofeno y derivados (1). El objetivo del presente trabajo es estudiar el efecto del método de preparación de SBA-16 modificada con titanio (características de las especies activas de Ti y/o TiO2) en el rendimiento de la ODS del DBT con H2O2 y acetonitrilo como solvente en condiciones suaves de reacción.
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    Esterification of succinic acid using sulfated zirconia supported on SBA-15
    (2021) Aguzin, Federico L.; Martínez, María Laura; Beltramone, Andrea Raquel; Padró, Cristina L.; Okulik, Nora
    Catalytic esterification of succinic acid with ethanol to obtain diethyl succinate (DES), a nontoxic plasticizer, is reported. Three sulfated zirconias supported on SBA-15 [SZ-SBA-15(X)] with Si/Zr molar ratios (X) of 10, 20, and 30 were syn- thesized and characterized. N2 adsorption/desorption isotherms and X-ray dif- fraction patterns evidenced preservation of the ordered mesoporous structure of the catalysts after incorporation of Zr. Yields of DES greater than 85 % were obtained at the final reaction time by using SZ-SBA-15(10) and SZ-SBA-15(20) catalysts, which were higher than those achieved with Amberlyst 36. Reuse of the SZ-SBA-15(20) catalyst showed that, even though the structure of the support was preserved, decreases in sulfur concentration and in the DES yield occurred.
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    Estudio de la influencia de la temperatura de síntesis y la concentración de surfactante en la síntesis de SBA-3
    (2014) Ponte, María Virginia; Martínez, María Laura; Gómez Costa, Marcos Bruno; Anunziata, Oscar Alfredo; Beltramone, Andrea Raquel
    En este trabajo se presentan resultados de preparación y caracterización de SBA-3, estudiando la variación de la temperatura de síntesis, así como la de la relación molar CTAB/TEOS. Condiciones de síntesis suaves (303 K) y adecuadas relaciones de surfactante/precursor de silicio conducen a un material mesoporoso con un ordenamiento regular hexagonal, característico de SBA-3 con elevada regularidad estructural.
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    EXperimental design optimization of the ODS of DBT using vanadium oXide supported on mesoporous Ga-SBA-15
    (2020) Rivoira, Lorena Paola; Cussa, Jorgelina; Martínez, María Laura; Beltramone, Andrea Raquel
    EXperiment design-response surface methodology is applied in this work to model and optimize the o Xidation of dibenzothiophene (DBT) using VOX-Ga-SBA-15 catalyst. The analyzed variables are the influence of the nature of the catalyst (V and Ga loading), the s ubstrate/catalyst mass ratio (g DBT/g of catalyst) and the o Xidant/substrate molar ratio (H2O2/DBT). The response analyzed is conversion of DBT at 15 min of reaction time. A set of re- sponse surfaces were obtained applying the BoX-Behnken Design. Based on statistical methodology it was pos- sible to find the best arrangement between the amounts of the gallium heteroatom and the vanadium active species. The higher levels of the objective function were obtained employing the catalyst with 4 wt.% of gallium and 6 wt.% of vanadium; the optimal ratio between g DBT/g of catalyst was 4 and the molar ratio between H2O2/DBT was 5. Gallium incorporation as heteroatom in tetrahedral position allowed the better anchorage ofthe active species of vanadium, generating a very well dispersed catalyst. The optimized catalyst minimized the mass transfer limitation and moreover, was active after several recycles. The best catalyst was likewise very active for the oXidation of the most refractory sulfur compounds as benzothiophene and 4,6-dimetyldi- benzothiopene.
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    Experimental desing optimization of the ODS of DBT using V2O5 supported on GA-SBA-15.
    (Univesidsad Tecnológica Nacional., 2020) Rivoira , Lorena Paola; Cussa , jorgelina; Martínez , María Laura; Beltramone, Andrea Raquel; Martínez , María Laura; Cussa , jorgelina
    Experiment design-response surface methodology (RSM) was used in this work to model and optimize one response in the oxidative desulfurization of dibenzothiophene with hydrogen peroxide using VOx Ga-SBA-15 catalysts with different Ga/Si and V/Si ratios. In this study, we analyze the influence of the nature of the catalyst (metal/Si ratio), the substrate/catalyst mass ratio and the oxidant/substrate ratio as factors for the design. The response analyzed was conversion at 15 min of reaction time. The response surfaces were obtained with the Box– Behnken Design, finding the best combination between the reaction parameters that allowed optimizing the process. By applying the statistic methodology, the higher levels of the objective function were obtained employing the catalyst with 4 wt.% of gallium and 6 wt.% of vanadium; the optimal ratio between g DBT/g of catalyst was 4 and the molar ratio H2O2/DBT was 5. The incorporation of gallium as heteroatom in tetrahedral position allows the better anchorage of the active species of vanadium generating a very well dispersed catalyst. Structural and textural characterization of the catalysts were performed by means of XRD, N2 adsorption, UV–Vis–DRS, XPS, NMR, TEM, Raman, TPR and Py-FTIR. UV–Vis–DRS and Raman demonstrated that highly dispersed vanadium pentoxide crystallites are responsible for the high activity in the sulfur removal. The high dispersion depended on the vanadium loading and on the nature of the support. The experiment design was able to find the best combination between the heteroatom and the vanadium active site in order to find the most active catalyst for ODS of DBT at the optimized experimental conditions.
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    Experimental desing optimization of the ods of DBT using V2O5 supported on GA-SBA-15.
    (Univesidsad Tecnológica Nacional, 2017) Rivoira, Lorena Paola; Cussa, jorgelina; Martínez , María Laura; Beltramone, Andrea Raquel; Martínez , María; Cussa, jorgelina
    Experiment design-response surface methodology (RSM) was used in this work to model and optimize one response in the oxidative desulfurization of dibenzothiophene with hydrogen peroxide using VOx-Ga-SBA-15 catalysts with different Ga/Si and V/Si ratios. In this study, we analyze the influence of the nature of the catalyst (metal/Si ratio), the catalyst/substrate ratio and the oxidant/substrate ratio as factors for the design. The response analyzed was conversion at 15 min of reaction time. The response surfaces were obtained with the Box–Behnken Design, finding the best combination between the reaction parameters that allowed optimizing the process. By applying the statistic methodology, the higher levels of the objective function were obtained employing the catalyst with Ga/Si and V/Si ratios of 1/15 and 1/25, respectively. Structural and textural characterization of the catalysts were performed by means of XRD, N2 adsorption, UV–Vis–DRS, XPS, NMR, TEM, Raman, TPR and Py-FTIR. UV–Vis–DRS and Raman demonstrated that highly dispersed vanadium pentoxide crystallites are responsible for the high activity in the sulfur removal. The high dispersion depended on the vanadium loading and on the nature of the support.
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    Experimental Desing Optimization of the tetralin Hydrogenation over Ir-Pt-SBA-15.
    (Univesidsad Tecnológica Nacional, 2016) Vallés , Verónica Alejandra; Ledesma, Brenda Cecilia; Rivoira , Lorena Paola; Cussa , jorgelina; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Cussa , jorgelina; Rivoira , Lorena Paola; Ledesma, Brenda
    Experiment design-response surface methodology (RSM) is used in this work to model and optimize two responses in the hydrogenation of tetralin to decalin using bimetallic Ir–Pt-SBA-15 catalyst. In this study, we analyze the influence of the nature of the catalyst (metal molar fraction and metal loading), the catalyst/substrate ratio and the temperature of the reaction as factors for the design. The responses analyzed were conversion at 3 h and at 5 h of reaction time. The response surfaces were obtained with the Box–Behnken design, finding the best combination between the reaction parameters that allowed optimizing the process. By applying the statistic methodology, the higher levels of the two objective functions were obtained employing the catalyst with 1 wt.% of iridium and 0.7–0.8 wt.% of platinum; the optimal ratio between mass of catalyst and mole of tetralin was 17–19 g/mol and temperature between 200 and 220 ◦C.
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    Experimental desing optimization of the tetralin hydrogenation over Ir-Pt-SBA-15.
    (Univesidsad Tecnológica Nacional., 2015) Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Rivoira , Lorena Paola; Cussa , jorgelina; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Cussa , jorgelina; Rivoira , Lorena Paola; Ledesma , Brenda Cecilia
    Experiment design-response surface methodology (RSM) is used in this work to model and optimize two responses in the hydrogenation of tetralin to decalin using bimetallic Ir–Pt-SBA-15 catalyst. In this study, we analyze the influence of the nature of the catalyst (metal molar fraction and metal loading), the catalyst/substrate ratio and the temperature of the reaction as factors for the design. The responses analyzed were conversion at 3 h and at 5 h of reaction time. The response surfaces were obtained with the Box– Behnken design, finding the best combination between the reaction parameters that allowed optimizing the process. By applying the statistic methodology, the higher levels of the two objective functions were obtained employing the catalyst with 1 wt.% of iridium and 0.7–0.8 wt.% of platinum; the optimal ratio between mass of catalyst and mole of tetralin was 17–19 g/mol and temperature between 200 and 220 ◦C
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    Experimental Desing Optimization of the tetralin Hydrogenation over Pt-Ir/SBA-15.
    (Univesidsad Tecnológica Nacional, 2015) Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Rivoira , Lorena Paola; Cussa , jorgelina; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Cussa , jorgelina; Rivoira , Lorena Paola; Ledesma , Brenda
    The oil refining industry has a difficult challenge to meet the increasingly stringent regula tions on environmental issues. Contaminants such as sulfur, nitrogen, fused ring aromatic compounds or metals are the principal to remove to achieve "green" fuels. The hydrotreating (HDT) is one of the processes most used in the refinery to remove these contaminants. To optimize the gas oil hydrotreater, it is crucial to understand the aromatic hydrogenation reac tion chemistry occurring in the gas oil hydrotreater. To find alternative processes, it is neces sary to develop new and more active catalysts to replace the current ones. Bimetallic Pt–Pd catalysts have received considerable attention, because they show high actvity in a variety of catalytic applications [1,2]. From a fundamental point of view, exploring bimetallic catalysts also allows better understanding of mechanisms and variables involved in the catalytic reac tions. The features of the catalysts here studied are going to be correlated with their catalytic performance in the hydrogenation of tetralin. The final goal is to find the optimal proportion of each metal in order to be more active and the best reaction conditions. The statistical expe riments design is the process of planning an experiment to obtain appropriate data that can be analyzed by statistical methods, to produce concrete and valid conclusions [3]. One of the main advantages in the response curve is to visualize the response for all levels of the experi mental factors Experiment design response surface methodology (RSM) is used in this work to model and to optimize the process
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    Experimental Desing Optimization of the tetralin Hydrogenation over Pt-Ir/SBA-15.
    (Univesidsad Tecnológica Nacional., 2015) Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Rivoira , Lorena Paola; Cussa , jorgelina; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Cussa , jorgelina; Rivoira , Lorena Paola; Ledesma , Brenda Cecilia
    he oil refining industry has a difficult challenge to meet the increasingly stringent regula tions on environmental issues. Contaminants such as sulfur, nitrogen, fused ring aromatic compounds or metals are the principal to remove to achieve "green" fuels. The hydrotreating (HDT) is one of the processes most used in the refinery to remove these contaminants. To optimize the gas oil hydrotreater, it is crucial to understand the aromatic hydrogenation reac tion chemistry occurring in the gas oil hydrotreater. To find alternative processes, it is neces sary to develop new and more active catalysts to replace the current ones. Bimetallic Pt–Pd catalysts have received considerable attention, because they show high actvity in a variety of catalytic applications [1,2]. From a fundamental point of view, exploring bimetallic catalysts also allows better understanding of mechanisms and variables involved in the catalytic reac tions. The features of the catalysts here studied are going to be correlated with their catalytic performance in the hydrogenation of tetralin. The final goal is to find the optimal proportion of each metal in order to be more active and the best reaction conditions. The statistical expe riments design is the process of planning an experiment to obtain appropriate data that can be analyzed by statistical methods, to produce concrete and valid conclusions [3]. One of the main advantages in the response curve is to visualize the response for all levels of the experi mental factors Experiment design response surface methodology (RSM) is used in this work to model and to optimize the process.
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    HDN of indole over Ir-modified Ti-SBA-15.
    (Univesidsad Tecnológica Nacional., 2015) Ledesma , Brenda Cecilia; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel
    The hydrodenitrogenation of indole has been studied over a series of Ti-modified SBA-15 supports and their respective Ir-catalysts. Ti-SBA-15 was synthesized using sol-gel method and Ti was added during the synthesis using Tetraethyl Orthotitanate. Iridium was added by wetness impregnation. The acidity of Ti-SBA-15 was modified adding F or Al in order to improve the catalytic activity. The catalysts pre pared were extensively characterized by X-ray diffraction (XRD), N2 adsorption isotherms, UV–vis-DRS, Raman spectroscopy, 27 Al-MAS-NMR spectroscopy, XPS, TEM-EDS, Py-FTIR, H2-Chemisorption and TPR. UV–vis-DRS and Raman spectroscopy confirmed that Ti was incorporated in tetrahedral coordination in the framework of the SBA-15. The analysis showed that the mesoporous structure was maintained after F or Al incorporation. 27 Al-MAS-NMR spectroscopy indicated that aluminum was incorporated mainly in Td positions. The results showed that Ti incorporation helps to reduce significantly the size of iridium crystallites and improves its dispersion considerably. Ir/Ti-SBA-15 modified with Al, with Bronsted acid ity, was the most active catalyst for indole HDN, in mild conditions in a Batch reactor. The experimental data for indole hydrodenitrogenation was quantitatively represented by a Langmuir–Hinshelwood type rate equation
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    HDT of the model diesel feed over Ir-modified Zr-SBA-15 catalysts
    (2018) Vallés, Verónica Alejandra; Yanika, Sa-ngasaeng; Martínez, María Laura; Siriporn, Jongpatiwut; Beltramone, Andrea Raquel
    Iridium catalyst using different zirconium modified-SBA-15 supports were tested in the HDT of tetralin and typical sulfur and nitrogen compounds present in diesel feed. The zirconium modified-SBA-15 supports were synthesized by sol-gel method using two sources of zirconium, zirconyl chloride and zirconium (IV) propoXide. Regarding XRD, N2 adsorption isotherms and TEM, we obtained better textural and structural properties using the alkoXide, especially when lactic acid was added in order to decrease the hydrolysis rate of zirconium propoXide. In addition, XPS and DRUV-Vis demonstrated that zirconium was incorporated mainly as tetrahedral Zr4+ species NH3-TPD showed that higher acidity is observed when tetrahedral Zr4+ species are present. Iridium dispersion was determined by TEM and H2-chemisorption and reducibility by XPS and TPR. Among the catalysts prepared, the catalyst synthesized using zirconium propoXide and lactic acid presented the highest dispersion, lowest cluster size and lowest reduction temperature. Consequently, this was the most active catalyst for the hydrogenation of tetralin, the HDN of indole and quinoline and the HDS of dibenzothiophene (DBT) and 4,6- dimethyldibenzothiophene (4,6-DMDBT). The presence of Zr+4 had a remarkable effect on the dispersion and reducibility capacity of the iridium actives species. In addition, the presence of moderate acidity in this material gives the best catalyst for HDN and HDS in the studied conditions. The inhibition effect of the sulfur and nitrogen compounds over tetralin hydrogenation was studied using individual feeds and a miXture feed. We observe that 4,6-DMDBT and quinoline were the most refractory compounds and they showed the highest inhibition effect. Tetralin hydrogenation was stronger inhibited when using the miXture feed compared with the individual feeds. This can be explained in terms of the competition between the different compounds that retard the rate of hydrogenation of tetralin. However, a high conversion of tetralin was achieved even when 300 ppm of S or N was
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    HDT process performance over noble metal-mesoporous catalysts
    (2022) Vallés, Verónica Alejandra; Ledesma, Brenda Cecilia; Beltramone, Andrea Raquel
    The greater concentration of market demand in the diesel range forces refiners to consider redirecting internal refinery cuts to new hydrocracking units to increase the contribution to the gasoline and diesel pool. These requirements drive advances particularly in hydrotreating technologies (HDT). The need to reduce the level of sulfur and polyaromatics in diesel fuel to values ??of a few ppm and the need to process heavy cuts with a high degree of aromaticity has motivated the appearance of new, more efficient processes. In recent years, bimetallic catalysts have received much attention, since they can combine two or more functions. The functionality of a catalyst can be due to active sites generated by supported metals and the interaction with the support. Pt-Pd catalysts have been extensively studied in order to improve tolerance to sulfur and other contaminants. They showed higher activity, stability and resistance to poisons compared to monometallic Pt or Pd catalysts. In bimetallic catalysts, the formation of the alloy creates electrondeficient species, more resistant to poisoning, in the case of Pd, which alone or alloyed with Pt, has a high hydrogenating and thio-resistant capacity and has begun to be used in industrial dearomatization units. The objective of this work is to evaluate the activity of all the synthesized catalysts in typical catalytic hydrotreating reactions. Performing first a kinetic study in a Batch reactor to the best catalysts that will then be tested in a continuous flow reactor in operating conditions close to industrial ones. With this objective, catalysts supported on SBA-16 were synthesized. This mesoporous has a high surface area and good characteristics of thermal stability, against the conditions set. The support was modified by incorporating Al indirectly and then impregnated with Ir, Pt and Pd. The behavior of the synthesized catalysts was studied against a commercially used catalyst and another support widely used in the industry, such as alumina. The catalysts were characterized by XRD, FTIR, NMR, TPR and N2 adsorption- desorption isotherms.
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    Hidrogenación de tetralin en presencia de quinolina sobre Ir/SBA-16 modificada con titanio
    (2014) Ledesma, Brenda; Vallés, Verónica; Rivoira, Lorena Paola; Anunziata, Oscar Alfredo; Beltramone, Andrea Raquel
    En el presente trabajo informamos resultados de la hidrogenación efectiva de tetralin en presencia de quinolina, en condiciones menos severas que las industriales; para lo cual desarrollamos un nuevo material catalítico mesoporoso Ir/SBA-16 modificado con titanio. La incorporación de Ti facilitó la mayor y mejor homogeneidad en la dispersión de partículas de Ir metálico (Ir0). Para conocer el efecto en la dispersión del metal de transición (1), el Ti fue incorporado vía post síntesis como TiO2 y en red empleando el método sol-gel obteniendo así los catalizadores Ir/TiO2-SBA-16 e Ir/Ti-SBA-16.
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    Hidrogenación de tetralin utilizando un catalizador bifuncional de iridio/platino-SBA-15
    (2014) Vallés, Verónica; Ledesma, Brenda; Rivoira, Lorena Paola; Cussa, Jorgelina; Martínez, María Laura; Anunziata, Oscar Alfredo; Beltramone, Andrea Raquel
    Los catalizadores bimetálicos de Pt–Pd han recibido considerable atención debido a que demuestran tener una alta actividad en una amplia variedad de aplicaciones catalíticas (1). Con alta actividad, selectividad y estabilidad, comparada con catalizadores monometálicos de Pt y Pd. Por ejemplo, catalizadores bimetálicos Pt-Pd muestran tener mayor resistencia frente a envenenamientos en comparación con catalizadores de Pt (2-4). Las características estudiadas del catalizador serán correlacionadas con su performance catalítica en la hidrogenación del tetralin. El objetivo final es encontrar la proporción óptima de cada uno de los metales de forma de lograr la mayor actividad en dicho proceso.