UTN- FRC -Producción Académica de Investigación y Desarrollo
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Item RSM in the analysis of conversion of DBT in oxidative desulfurization using vanadium-SBA-15 catalysts modified with AI and Ga.(Univesidsad Tecnológica Nacional., 2018) Rivoira , Lorena Paola; Cussa , jorgelina; Martínez , María Laura; Beltramone, Andrea Raquel; Martínez , María Laura; Cussa , jorgelinaExperiment design-response surface methodology (RSM) was used 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. Conversion at 15 min is the analyzed response. 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; optimal ratio between g DBT/g of catalyst was 4 and 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.Item Síntesis y caracterización de un catalizador soportado iridio/platino-SBA-15 para su aplicación en la Hidrogenación de Tetralin.(Univesidsad Tecnológica Nacional, 2014) 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, BrendaIn this paper the effect of the dispersion of noble metals Ir and Pt and interaction with the SBA-15 support was studied by relating them to the catalytic activity of the catalyst in the hydrogenation reaction of Tetralin using a Parr reactor at 250°C and 15 atm. With this objective Ir/Pt-SBA-15 modified catalysts were synthesized with different % of Ir and Pt. The mesostructure of SBA-15 support gives a relatively high thermal stability and proper pore diameter can converts large molecules such as those present in the liquid fuels. The support was prepared by the sol-gel method. The catalytic site was obtained using incipient co impregnation method. The material was characterized by X-ray diffraction (XRD) and TEM). The metal dispersion was calculated by H2 chemisorption and TEM. Iridium / Platinum particles (d = 2,0-4,0 nm) homogeneously dispersed were obtained with a dispersion of more than 60%.Item 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, jorgelinaExperiment 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.Item Iron-modified mesoporous materials as catalysts for ODS of sulfur compounds(2020) Rivoira, Lorena Paola; Juárez, Juliana María; Martínez, María Laura; Beltramone, Andrea RaquelFe-modified mesoporous catalysts were used in the ODS of DBTs using H2O2 as oXidant and acetonitrile as solvent. SBA-15, MCM-48, CMK-3 and CMK-1 were used as supports. Iron was incorporated using iron nitrate by wetness impregnation. The catalysts were characterized by XRD, N2 isotherms, TEM, XPS and ICP. We developed catalysts with high specific surface area, pore volume and narrow mesopore size distribution and highly dis- persed Fe- species. The catalysts were tested in the o Xidative desulfurization of different sulfur compounds as benzothiophene, dibenzothiopene and 4,6-dimethyl dibenzothiopene. The catalyst prepared using CMK-3 as support was the most active for the ODS reaction. The good activity was related with the high dispersion of the iron oXides, mainly in the magnetite phase. Temperature, hydrogen peroXide and sulfur initial concentration were studied using Fe-CMK-3 in the oXidation of DBT. The optimal operation conditions were determined. Fe- CMK-3 is an active and stable catalyst to be applied in the industrial process of ODS.Item Síntesis y caracterización de un catalizador soportado iridio/platino-SBA-15 para su aplicación(2014) Vallés, Verónica; Ledesma, Brenda; Rivoira, Lorena Paola; Cussa, Jorgelina; Martínez, María Laura; Anunziata, Oscar Alfredo; Beltramone, Andrea RaquelEn el presente trabajo se estudió el efecto de la dispersión de metales nobles Ir y Pt y la interacción con el soporte SBA-15, relacionándolos con la actividad catalítica del catalizador en la reacción de hidrogenación del Tetralin utilizando un reactor Parr a 250°C y 15 atm. Con este objetivo se sintetizaron catalizadores Ir/Pt-SBA-15 modificados con distintos % de Ir y Pt. La mesoestructura del soporte SBA-15 le confiere una estabilidad térmica relativamente alta y el diámetro apropiado de poro permite convertir moléculas voluminosas como las presentes en los cortes de combustibles líquidos. El soporte fue preparado por el método de sol-gel. Para la obtencion del sitio catalitico se utilizó l método de impregnación incipiente. Se disuelven el Acetil acetonato de Iridio (IrAcAc) y el Acido cloroplatinico hidratado (H2PtCl6.H2O) en 50 ml de etanol a 50ºC con reflujo. Luego se agrega a la SBA-15 previamente pesada la solución y se lo lleva a un evaporador rotatorio a 60 ºC y 70 rpm hasta lograr evaporar todo el solvente. Luego se deja secando en estufa a 110 ºC por 24 h. Posteriormente es calcinado en mufla a 500 ºC por 5 horas, seguido de reducción con hidrógeno. El material fue caracterizado mediante difracción de rayos X (XRD), se puede observar que conserva la estructura mesoporosa a bajo ángulo, mientras que a alto ángulo se observan los índices de refracción característicos de Ir y Pt metálicos. También fueron caracterizados por XPS y TEM. La dispersión del Me fue calculada mediante quimisorción de H2 se obtuvieron partículas de iridio/Platino (d= 4,0-2.0 nm) homogéneamente disperso, con una dispersión de más del 60%. Se obtuvo una