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    Hidrodenitrogenación de Indol utilizandocatalizadores de Ir soportado sobre SBA-15 modificada con Ti.
    (Univesidsad Tecnológica Nacional., 2016) Ledesma , Brenda Cecilia; Vallés , Verónica Alejandra; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Vallés , Verónica Alejandra
    La hidrodenitrogenación de indol se estudió utilizando una serie de catalizadores de Ir soportado sobre SBA 15 modificada con Ti. El mesoporoso modificado Ti-SBA-15 se sintetizó usando el método sol-gel. El iridio fue incorporado mediante la técnica de impregnación húmeda incipiente. Con el fin de mejorar la actividad catalítica se modificó la acidez del material mesoporoso añadiendo F o Al. Los catalizadores fueron caracterizados por difracción de rayos X (XRD), isotermas de adsorción de N2, UV-Vis-DRS, espectroscopía Raman, espectroscopía 27Al-MAS-RMN, XPS, TEM, Py-FTIR y TPR. Los análisis confirman que el Ti fue incorporado en coordinación tetraédrica dentro de la SBA-15 y que la estructura mesoporosa se mantuvo después de la incorporación de F o Al. La espectroscopía27Al-MAS-RMN indica que el aluminio se incorporó principalmente en posicion tetraédrica. Los resultados mostraron que la incorporación del Ti ayuda a reducir significativamente el tamaño de los clusters de Iridio y mejora considerablemente su dispersión. El catalizador Ir-Ti-SBA-15, modificado con Al, fue el catalizador más activo para la hidrodenitrogenación de indol, en condiciones suaves en un reactor discontinuo. Los datos experimentales para la hidrodenitrogenación de indol fueron cuantitativamente representados por una ecuación de velocidad del tipo Langmuir-Hinshelwood. Palabras claves: hidrodenitrogenación, titanio, mesoporoso, clusters de Iridio, cinética
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    VOx-SBA-15 modified with AI and Ga in ODS of DBT.
    (Univesidsad Tecnológica Nacional., 2018) Rivoira , Lorena Paola; Martínez , María Laura; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Martínez , María Laura
    In order to adapt current processes to the strict regulatory requirements, several technologies have been developed for deep desulfurization of diesel fuel. The major portion of sulfur compounds in light cycle oils (LCO) are dibenzothiophene (DBT) and alkyl-dibenzothiophenes, which are not easily removable by hydrotreating. Vanadium oxides supported on mesoporous SBA-15 catalysts with different vanadium loadings were studied in the oxidative desulfurization (ODS) of dibenzothiophene. The catalytic activity was improved when SBA-15 framework was modified with Al and Ga as heteroatom substituting Si. 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 VO4-3 species are responsible for the high activity in the sulfur removal. The Ga modified support with an intermediate V/Si ratio was the most active catalyst, using hydrogen peroxide as oxidant and acetonitrile as solvent. 100% of DBT elimination was attained at a short time in mild conditions. Gallium and aluminum incorporation modified successfully the nature of the SBA-15 surface by generating Bronsted and Lewis acidity. The interaction between the acid sites with the vanadium active sites improved the activity of the catalysts. The more acidic support allowed better dispersion of the vanadium species due to stronger interaction metal-support. The reusability of the catalysts indicates that vanadium oxide supported on mesoporous SBA-15 modified with Ga and Al are potential catalysts for the ODS of dibenzothiophene.
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    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 , jorgelina
    Experiment 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.
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    Hidrogenación de tetralin sobre Ir-Pt-SBA-15. Parte 2: Optimización por Diseño de Experimentos.
    (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
    La Metodología Diseño de Experimentos - Superficie de Respuesta – se utiliza en este trabajo para modelar y optimizar 2 respuestas en la reacción de hidrogenación de tetralin a decalin usando un catalizador bimetálico Ir-Pt-SBA-15. En este estudio se analizó la influencia de la naturaleza del catalizador, la relación catalizador/sustrato y la temperatura de reacción como factores del diseño. Las respuestas analizadas fueron conversión a 3 y 5 horas Las Superficies de Respuesta fueron obtenidas mediante un diseño Box-Behnken a fin de encontrar la mejor combinación de los distintos parámetros para optimizar el proceso. La metodología estadística aplicada indica que las conversiones más altas de ambas respuestas, a 3 y 5 horas, se obtienen trabajando en el siguiente rango: Catalizador: 1% Ir y 0.7-0.9 %(p/p) Pt; Relación: 17-19 g cat/ mol TL y Temperatura: 200-220°C.
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    Hidrogenación de tetralin sobre Ir-Pt-SBA-15. Parte 1: Síntesis, caracterizacíon y actividad catalítica.
    (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
    Se estudia aquí la hidrogenación de tetralin a decalin utilizando un catalizador bimetálico Ir-Pt SBA-15. En esta Parte se describe la síntesis de los catalizadores, la preparación de la matriz de SBA 15 y el método de co-impregnacion mediante el cual se incorporaron los metales en diferentes proporciones y carga total metalica. Los catalizadores fueron caracterizados por XRD, TEM, análisis fisicoquimicos, XPS, SEM y EDX. En la Parte 2 de este trabajo se analizará la influencia de la naturaleza del catalizador, la relación catalizador sustrato y la temperatura de reacción como factores de un Diseño de Experimentos para optimizar el proceso.
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    Ordered mesoporous SBA-15 host for Ketorolac-Tromethamine loading and release behavior.
    (Univesidsad Tecnológica Nacional, 2017) Cussa , jorgelina; Juárez , Juliana María; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Juárez , Juliana María
    The ordered mesoporous silica SBA-15 has been applied in studies of ketorolac tromethamine adsorption and release. The SBA-15 materials with hexagonal and regular structure were obtained using a triblock copolymer Pluronic P123 as a template and TEOS as a silica source. Ketorolac tromethamine was adsorbed into SBA-15 silica nanochannels using ethanol as solvent. The physicochemical and textural properties of SBA-15 and ketorolac tromethamine/SBA-15 were characterized by X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, Fourier transform infrared spectroscopy and BET surface studies. The composite SBA-15/KETO shows characteristic bands of both, drug materials and the inorganic framework. This indicates that KETO was adsorbed into SBA-15 channel surface without affecting the chemical structure or composition of KETO. Drug release was evaluated by soaking the loaded silica mesoporous material into a solution of HCl (0.1N) at initial time (0 - 2 h) and buffer pH 7 at high times at 37 ºC under continuous stirring. Oral commercial Keto tablets (Dolten®) and Keto solution (Keto power) were study for the contrast. Release studies were performed in order to evaluate the required therapeutic efficacy. SBA-15 provides significant improvement in the controlled release of ketorolac tromethamine and enhance a good analgesia effect.
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    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, Brenda
    In 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%.
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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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    Ketorolac-tromethamine contained in SBA-15 host as a drug release system,
    (Univesidsad Tecnológica Nacional, 2017) Cussa , jorgelina; Prados, Antonella; Juárez , Juliana María; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Juárez , Juliana María
    Drug delivery is an emerging field mainly focused on targeting drugs. The goal of this targeted delivery is to transport an amount of drugs to desirable sites (such as tumors and diseased tissues) while minimizing unwanted side effects of the drugs on other tissues[1]. Controlled drug delivery systems can achieve precise spatial and temporal delivery of therapeutic agents to the target site[2]. The ordered mesoporous silica SBA-15 has been applied in studies of ketorolac tromethamine adsorption and release. The SBA-15 materials with hexagonal and regular structure were obtained using a triblock copolymer Pluronic P123 as a template and TEOS as a silica source[3]. Ketorolac tromethamine was adsorbed into SBA-15 silica nanochannels using ethanol as solvent. The physicochemical and textural properties of SBA-15 and ketorolac tromethamine/SBA-15 were characterized by X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, Fourier transform infrared spectroscopy and BET surface studies. Drug release was evaluated by soaking the loaded silica mesoporous material into a solution of HCl (0.1N) at initial time (0 - 2 h) and buffer pH 7 at high times at 37 ºC under continuous stirring. Oral commercial Keto tablets (Dolten®) and Keto solution (Keto power) were study for the contrast. Release studies were performed in order to evaluate the required therapeutic efficacy. In this work, we have shown a promising drug storage material for the effective encapsulation and controlled release of KETO, achieving the required therapeutic efficacy. SBA-15/KETO shows characteristic bands of both, drug materials and the inorganic framework. This indicates that KETO was adsorbed into SBA-15 channel surface without affecting the chemical structure or composition of KETO. The study also demonstrates the storage capacity and release properties of SBA-15 containing KETO. The release of KETO contained in SBA-15 can offer significant improve in controlled drug release and enhance a good analgesia effect.
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    Nanostructured SBA-15 host: synthesis, characterization and application in ketorolac-tromethamine release system.
    (Univesidsad Tecnológica Nacional, 2016) Cussa , jorgelina; Juárez , Juliana María; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Juárez , Juliana María
    The ordered mesoporous silica SBA-15 has been applied in studies of ketorolac tromethamine adsorption and release. The SBA-15 materials with hexagonal and regular structure were obtained using a triblock copolymer Pluronic P123 as template and TEOS as a silica source[1]. Drug delivery is an emerging field mainly focused on aiming drugs. The goal of this targeted delivery is to transport an amount of drugs to desirable sites (such as tumors and diseased tissues) while minimizing unwanted side effects of the drugs on other tissues [2]. Controlled drug delivery systems can achieve precise spatial and temporal delivery of therapeutic agents to the target site. Ketorolac tromethamine was adsorbed into SBA-15 silica nanochannels using ethanol as solvent. The physicochemical and textural properties of SBA-15 and ketorolac tromethamine/SBA-15 were characterized by X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, Fourier transform infrared spectroscopy and BET surface studies. Drug release was evaluated by soaking the loaded silica mesoporous material into a solution of HCl (0.1N) at 37 ºC under continuous stirring. Release studies were performed in order to evaluate the required therapeutic efficacy. SBA-15 provides significant improvement in the controlled release of ketorolac tromethamine [3]. In this work, we have shown a promising drug storage material for the effective encapsulation and controlled release of KETO, achieving the required therapeutic efficacy. SBA-15/KETO shows characteristic bands of both, drug materials and the inorganic framework. This indicates that KETO was adsorbed into SBA-15 channel surface without affecting the chemical structure or composition of KETO. The study also demonstrates the storage capacity and release properties of SBA-15 containing KETO. The release of KETO contained in SBA-15 can offer significant improve in controlled drug release and enhance a good analgesia effect.