Browsing by Author "Beltramone , Andrea Raquel"

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    CMK-3 modificada con titanio obtenida mediante un novedoso y rápido método de síntesis aplicada en la desulfuración oxidativa de compuestos organosulfurados.
    (Univesidsad Tecnológica Nacional., 2018) Rivoira , Lorena Paola; Ledesma, Brenda Cecilia; Juárez , Juliana María; Beltramone , Andrea Raquel; Juárez , Juliana María; Ledesma, Brenda
    El nanomoldelado de materiales ha sido el único método para crear materiales mesoporosos de carbono, utilizando plantillas inorgánicas (Ezzeddine et al., 2016). Involucra una última etapa donde se elimina el agente plantilla, lo cual lo hace complicado, largo y de elevado costo. Recientemente Ledesma et al. (2017) demostraron la posibilidad de un método de síntesis más corto para obtener CMK-3 modificada con Ti incorporando las especies de Ti directamente en la estructura del carbón mesoporoso utilizando Ti-SBA-15 como agente plantilla. En la reacción de ODS ocurre la oxidación de aquellos compuestos de S más refractarios en la HDS, utilizando de un agente oxidante en presencia de un catalizador (Subhan et al., 2012). Es necesario agregar un solvente polar al sistema, capaz de extraer las moléculas de S desde la fase diesel para que pueda estar en contacto con el agente oxidante (H2O2, polar) y el catalizador. En el presente trabajo se evalúa la actividad en la ODS de carbón mesoporoso CMK-3 modificado con Ti, sintetizado mediante un novedoso método más corto.
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    Eliminación de azufre mediante desulfuración oxidativa con Ti-SBA-16. Parte I. Síntesis y caracterización.
    (Univesidsad Tecnológica Nacional., 2015) Rivoira , Lorena Paola; Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Ponte , María Virginia; Martínez , María Laura; Beltramone , Andrea Raquel; Martínez , María Laura; Ponte , María Virginia; Ledesma , Brenda Cecilia; Ledesma , Lorena Paola; Vallés , Verónica Alejandra
    Se desarrollaron catalizadores tipo SBA-16 modificados con Ti como TiO2 y como heteroatomo y se probaron en la desulfuración oxidativa (ODS) del dibenzotiofeno predominante en el combustible líquido. Se utilizó TiO2 puro como referencia para comparar la actividad catalitica. Los catalizadores fueron caracterizados mediante análisis químico, XRD, EDX y TEM. El estado de coordinación tetraédrico del titanio (en la muestra de Ti-SBA-16) u octaédrico (en la muestra de TiO2/SBA-16) en la matriz de sílice se determinó por XPS, UV-vis DRS, FTIR, Raman y XANES. La actividad catalítica se muestra en la Parte 2 de este trabajo.
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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 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 v1/15 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 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 vanadium oxide supported on mesoporous GA-SBA-15.
    (Univesidsad Tecnológica Nacional ., 2018) Rivoira , Lorena Paola; Cussa , jorgelina; Vallés , Verónica Alejandra; Martínez , María Laura; Beltramone , Andrea Raquel; Martínez , María Laura; Vallés , Verónica Alejandra; Cussa , jorgelina
    En el presente trabajo se utiliza el diseño experimental de superficies de respuesta (RSM) para modelar y optimizar la oxidación de dibenzotiofeno (DBT) utilizando VOx-Ga-SBA-15 como catalizador. Analizamos como influye la naturaleza del catalizador (carga de V y Ga), la relación másica substrato/catalizador y la relación molar oxidante/substrato como variables para el diseño. La respuesta analizada fue la conversión a los 15 min de reacción. Las superficies de respuesta fueron obtenidas mediante el Diseño de Box-Behnken, encontrando así la mejor combinación entre los parámetros de reacción que permita optimizar el proceso. Los mayores valores de función objetivo se obtuvieron mediante el uso de la estadística, empleando el catalizador con 4 % p/p de galio y 6 % p/p de vanadio, la relación óptima entre g DBT/g de catalizador fue 4 y la relación molar H2O2/DBT fue 5. La incorporación de galio como heteroátomo en posición tetraédrica permite el mejor anclaje de las especies activas de vanadio generando un catalizador con muy buena dispersión. El diseño de experimento sirvió para encontrar la mejor combinación entre el heteroátomo y las especies activas de vanadio con el fin de hallar el catalizador mas activo para la oxidación de DBT en las condiciones experimentales óptimas.
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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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    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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    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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    Hydrodeoxygenation of guayacol over platinum modified mesoporous catalysts.
    (Univesidsad Tecnológica Nacional., 2018) Rivoira , Lorena Paola; Martínez , María Laura; Beltramone , Andrea Raquel; Martínez , María Laura
    Biomass pyrolysis results in fuel bio-oil which can be consider as a renewable petroleum alternative. Bio-oil obtained by this process presents high oxygen content, becoming into a corrosive and unstable fuel. Hydrodeoxygenation (HDO) is a catalytic treatment that improves the bio-oil characteristics. There are more than 400 organic compounds that can be found in bio oil. For that reason we selected guayacol (2-methoxyphenol ó 4-hydroxy-3-methoxybenzyl) as model compound to test the catalytic activity of the developed catalysts. The catalysts tested for hydrodeoxygenation (HDO) of guayacol to produce deoxygenated products such as benzene, toluene, ciclohexene and ciclohexane were platinum modified mesoporous SBA-15 and Ga-SBA 15. The synthetized catalysts were obtained by sol-gel method. Active platinum sites were incorporated by wet impregnation. The system reaction used for HDO is a 600 mL stirred autoclave (Parr Pressure Reactor 4536). Reaction conditions were carried out at 230°C and 12 atm of H2 under 500 rpm. Reactor feed consisted in 50 mL of a 1% w/v solution of guayacol in dodecane. Then, 200 mg of the catalyst was transferred to the reactor. Samples were taken every hour. Products were analysed with HP Series II GC and HP-5 capillary column and identified by GC/MS. Better catalytic results were obtained when Ga was introduced as heteroatom into the SBA-15 siliceous framework. Textural and structural properties of the Pt -supported mesoporous catalysts were determined along with the nature of the active site. The synthetized material were characterized before and after the incorporation of metal active site by XRD, HRTEM, SEM EDX, FTIR, XPS and N2 adsorption-desorption isotherms. Characterization results demonstrated that highly dispersed Pt species are responsible for the high activity in the guayacol conversion. The most active catalyst for HDO of guayacol was Pt/Ga-SBA-15 achieving 99 % of guayacol conversion in a relatively short time (4 h). Gallium atoms incorporated into the support modified the nature of the SBA-15 surface by conferring Bronsted and Lewis acidity. The acid sites are able to interact with the platinum active sites improving the activity of the catalyst. As consequence the gallium modified catalyst showed better dispersion of the Pt sites
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    Hydrogenation of tetralin in presence of nitrogen using a noble-bimetallic couple over a Ti-modified SBA-15.
    (Univesidsad Tecnológica Nacional., 2016) Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Pecchi, Gina; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Ledesma , Brenda Cecilia
    Monometallic Pt- and bimetallic Pt-Ir-modified Ti-SBA-15 were used in the hydrogenation of tetralin to decalin in the presence of 150 ppm of N as quinoline and indole at 250 ◦C and 15 atm of pressure of hydrogen, using a Parr reactor. The catalyst was synthesized using sol-gel method and Ti was added during the synthesis using Tetraethyl Orthotitanate. Pt/Ir was added by wetness impregnation. The catalysts prepared were extensively characterized by X-ray diffraction (XRD), N2 adsorption isotherms, UV–vis DRS, Raman spectroscopy, XPS, TEM-EDS 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 metal incorporation and Ti incorporation helps to reduce significantly the size of the metals clusters and improves its dispersion considerably. Pt-Ir/Ti-SBA 15 was the most active catalyst. The experimental data were quantitatively represented by a modified Langmuir-Hinshelwood type rate equation. The preliminary results show these materials as a promising catalyst for HDT reactions.
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    Hydrogenation of tetralin over Ir-TI02/SBA-16
    (Universidad Tecnológica Nacional, 2013) Ledesma, Brenda; Valles , Verónica; Martínez , Maria Laura; Anunziata, Oscar Alfredo; Beltramone , Andrea Raquel
    A titanium modified catalyst based on noble metal has been prepared with the main aim of obtaining thiotolerant catalysts to be used in second stage processes of mild-hydrotreating. We study the catalytic properties of 1 wt% Ir-containing mesoporous materials modified with TiO2 in the hydrogenation of tetralin to decalin in the presence of 100 ppm of dibenzotiophene at 250°C and 15 atm of pressure of hydrogen, using a Parr reactor. Titanium oxide was added via post synthesis with the purpose of improve iridium dispersion. Ir/mesoporous materials were prepared by wetness impregnation. The catalyst synthesized by us had good activity measured in tetralin hydrogenation at mild conditions. The preliminary results show these materials as a promising catalyts for HDS/HDN reactions.
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    Ir-Pt/SBA-15 applied in the optimization of tetralin hydrogenation.
    (Univesidsad Tecnológica Nacional., 2015) Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Rivoira , Lorena Paola; Cussa , jorgelina; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata; Cussa , jorgelina; Rivoira , Lorena Paola; Ledesma , Brenda Cecilia
    Bimetallic catalysts have received considerable attention for hydrotreating (HDT) because they show high activity. The features of the catalysts here studied are going to be correlated with their catalytic performance in the hydrogenation of tetralin at mild conditions. The final goal is to find the optimal proportion of each metal in order to be more active and the best reaction conditions (temperature and amount of catalyst). The statistical experiments 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. One of the main advantages in the response curve is to visualize the response for all levels of the experimental factors Experiment design response surface methodology (RSM) is used in this work to model and to optimize the process. Platinum and Iridium nanoparticles were incorporated into SBA-15 support by the wet co-impregnation method. Ir content was set as 1wt. % and Pt was varied from 0 to 1wt. %. The catalysts were characterized by XRD, BET, XPS, TEM, ICP and TPR. XRD profiles are characteristic of the two-dimensional p6mm hexagonal mesostructure with d100 spacing of 10.16 nm; where the d100 spacing upon Ir and Pt incorporation were quite similar to pristine SBA-15. The TEM images and XPS demonstrate that the metal particles were mainly present inside the porous and XPS and TPR corroborated the reduced state of the metals. The catalytic activity was measured in a 4563Parr reactor at 15 atm of hydrogen and 360 rpm. Feed consisted in 50 mL of tetralin in Dodecane, the amount of tetralin is set according to the ratio of catalyst mass/mass reagent corresponding to each reaction. The application of this methodology allows a better understanding of the influence of the different factors: content of metal on catalyst (A), relationship: mass of catalyst/reagent mass (B) and reaction temperature (C), on two responses: conversion at 3 h and at 5 h of reaction time. These factors were carefully selected taking account the influence of the parameters in the reaction. The design was analyzed by Statgraphics and Statistica Soft. We found that, the variable Catalyst has the best influence over the Conversion at the 95.0% confidence level, according to the Pareto.
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    Iron-modified mesoporous materials as catalysts for ODS of sulfur compounds.
    (Univesidsad Tecnológica Nacional, 2018) Rivoira , Lorena Paola; Juárez , Juliana María; Martínez , María Laura; Beltramone , Andrea Raquel; Juárez , Juliana María
    Mandatory environmental regulations have been legislated all over the world so the top permitted content of sulfur in diesel is 15 ppm. ODS is the oxidation of sulfur compounds present in diesel to form sulfoxides and sulfones. These substances are highly polar and hence easily removed by extraction with solvent. Oxidant agent commonly used are peroxides such as hydrogen peroxide and tert-butylhydroperoxide (Di Giusepe et al., 2009). Since Diesel is a non-polar liquid while H2O2 is a polar liquid, a polar solvent is needed. The formed polar products can be easily removed from the operation unit by liquid liquid extraction. Mesoporous materials have been tried showing potential catalytic applications. Transition metals are commonly used as catalyst in ODS such as Mo, Mn, Sn, Fe, Zn, V and Ti (Cedeño-Caero et al., 2011). In this work, we propose the application of different supports as SBA-15, MCM-48, CMK-1 and CMK-3 for the preparation of Fe-catalysts.
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    Material catalítico con estructura mesoporosa conteniendo galio, adsorción y polimerización de anilina del trabajo.
    (Univesidsad Tecnológica Nacional., 2018) Martínez , María Laura; Rivoira , Lorena Paola; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Rivoira , Lorena Paola
    La anilina (AN) es una base orgánica aromática débil y anfiprótica, que puede actuar como aceptor o donor de protones. La polianilina (PANI) existe en una variedad de formas. La forma de sal emeraldina (conductora, de color verde) o forma protonada de la polianilina tiene una conductividad en un nivel semiconductor de 100 S/cm, muchos órdenes de magnitud mayor que los polímeros comunes (aislantes, <10-9 S/cm), pero menor que los metales (conductores típicos, >104 S/cm). El material mesoporos SBA-3 ofrece oportunidades únicas para la preparación de nuevos materiales híbridos nanoestructurados En este sentido, el estudio de adsorción de anilina y su posterior polimerización sobre hospedajes tal como SBA-3 es de suma importancia (Anunziata et al., 2005, 2008). En este trabajo estudiamos la incorporación de galio en la estructura del material mesoporoso, con el fin de modificar la acidez intrínseca del material (Berrichi et al., 2006) y la adsorción de piridina en la superficie del mismo con el objetivo de determinar los sitios ácidos que posee este material. En adición se realizara estudios de adsorción/desorción de anilina y su posterior polimerización sobre el galosilicato mesoporoso Ga-SBA-3 que le confiere características únicas al compuesto, obteniéndose híbridos con características conductoras similares a las de un semiconductor inorgánico.
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    Material catalítico con estructura mesoporosa conteniendo galio, adsorción y polimerización de anilina.
    (Univesidsad Tecnológica Nacional., 2018) Martínez , María Laura; Rivoira , Lorena Paola; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Rivoira , Lorena Paola
    En este trabajo estudiamos la polimerización de anilina sobre el galosilicato mesoporoso del tipo Ga-SBA-3. Este material fue expuesto a vapores de anilina en equilibrio para obtener hospedajes saturados. La adsorción de anilina sobre estos materiales, sintetizados en nuestro laboratorio se estudió por espectroscopia infrarroja. La adsorción de anilina fue evaluada para luego polimerizar la anilina adsorbida para generar un composite de polianilina-hospedaje y obtener composites con propiedades únicas. Composites de polianilina, obtenidos por técnicas de polimerización in-situ, fueron caracterizados por espectroscopia infrarroja (FTIR), y difracción de rayos X (XRD). Los análisis FTIR del composite polianilina/Ga-SBA-3 (PANI/Ga-SBA-3) muestra bandas características de acuerdo a datos obtenidos en trabajos previos atribuidas al stretching quinoidal (N=Q=N) y al stretching C-C de anillo bencénico. Los análisis de XRD muestran que la polianilina está dentro de los canales del hospedaje. Palabras clave: Galosilicato, Ga-SBA-3, anilina, polianilina, PANI/Ga-SBA-3
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    Noble-bimetallic supported CMK-3 as a novel catalyst for hydrogenation of tetralin in the presence of sulfur and nitrogen.
    (Univesidsad Tecnológica Nacional., 2016) Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Juárez , Juliana María; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Juárez , Juliana María; Ledesma , Brenda Cecilia
    Carbon ordered mesoporous CMK-3 with high surface area and high pore volume promotes a very good dispersion of Pt or Ir monometallic and Pt-Ir-bimetallic crystallites in the carbon framework. High active and stable nanospecies are responsible for the good activity and selectivity found in the hydrogenation of tetralin to decalin in the presence of N as indole and S as dibenzothiophene under mild conditions in a Batch reactor. The catalysts prepared were extensively characterized by XRD, N2 adsorption isotherms, XPS, TEM, ICP, CO Chemisorption and TPR. The analysis showed that the carbon mesoporous structure was maintained after metal incorporation, and very high dispersed metal-supported catalyst was obtained. The activity was compared using the turnover number, Pt-Ir-CMK-3 being the most active cat alyst in the presence of the inhibitors. The bimetallic catalyst showed more resistance to inhibition than monometallic catalysts. The reusability of Pt-Ir-CMK-3 suggests that it is a potential catalyst for hydrotreating reactions.
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    Novel and simple one-pot method for the synthesis of Ti02 modified-CMK-3 applied in oxidative desulfurization of refractory organosulfur compounds.
    (Univesidsad Tecnológica Nacional., 2016) Rivoira , Lorena Paola; Ledesma , Brenda Cecilia; Juárez , Juliana María; Beltramone , Andrea Raquel; Juárez , Juliana María; Ledesma , Brenda Cecilia
    Ti-CMK-3 carbon mesoporous was prepared using a novel synthesis method. This new method avoids the hard template synthesis used commonly. The precursors of silicon, carbon and titanium are incorporated together with the other components during the only step of the synthesis. The method developed here, allows reducing time and energy consumption by 60% and thus, the cost of the overall process of synthesis. Structural and textural characterization of the titanium modified-mesoporous carbon was performed by N2 adsorption, XRD, UV–Vis DRS, XPS, Raman spectroscopy and TEM. The characterization results indicated that the textural and structural properties of the material synthesized by the short time method are comparable with the properties of the material prepared by the hard template method. Ti modified-mesoporous carbon was synthesized by dif- ferent methods in order to prepare catalysts to be tested in the oxidative desulfurization (ODS) of sulfur com- pounds. The catalyst prepared by the one-pot method is capable to oxidize high amount of sulfur (2000 ppm) in only 30 min of reaction time at 60–80 °C. The good performance and stability of the catalyst prepared using a novel synthesis method was attributed to well dispersed anatase nanospecies over the high area mesoporous carbon. Main advantage of the present study is the reduction of time and cost in the synthesis of the new material and the applicability for ODS reactions.
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    Novel preparation of titania-modified CMK-3 nanostructured material as support for Ir catalyst applied in hydrodenitrogenation of indole.
    (Univesidsad Tecnológica Nacional., 2018) Ledesma , Brenda Cecilia; Juárez , Juliana María; Vallés , Verónica Alejandra; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Vallés , Verónica Alejandra; Juárez , Juliana María
    Iridium catalyst was prepared using a novel titanium oxide-CMK-3 support synthesized as a replica of Ti-SBA-15. The catalyst was applied in the hydrodenitrogenation of indole. The activity was compared with an iridium catalyst supported over a grafted titanium CMK-3. Structural and textural characterization of the catalysts was performed by means of N2 adsorption, XRD, UV–Vis–DRS, Raman spectroscopy, XPS, TEM and H2 Chemisorption. Ir-Ti-CMK-3 was the most active catalyst for the hydrodenitrogenation reaction at mild conditions. Titanium oxide contained in carbon ordered mesoporous CMK-3 promotes a very good anchorage of iridium metallic clusters in the carbon framework reaching high active site distribution and more stable nanoclusters
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    Optimization of the synthesis of SBA-3 mesoporous materials by experimental desing.
    (Univesidsad Tecnológica Nacional., 2015) Ponte , María Virginia; Rivoira , Lorena Paola; Cussa , jorgelina; Martínez , María Laura; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Anunziata; Cussa , jorgelina; Rivoira , Lorena Paola
    SBA-3 mesoporous materials are characterized by hexagonal regular arrangements of channels with diameters >2 nm, high specific surface areas and high specific pore volumes. In the work reported herein, experimental design-response surface methodology (RSM) is used to model and optimize the synthesis conditions for SBA-3 mesoporous materials. In this study, we evaluate the influences of surfactant/silica source molar ratios, aging times, temperature and pH on the synthesis of SBA-3 mesoporous materials by analyzing the XRD intensities pertaining to the [100] signal. Response surfaces were obtained using the BoxeBehnken design, and the combination of reaction parameters was optimized. By applying statistical methodology, higher levels of the objective function (XRD intensities pertaining to the [100] signal) were obtained using cetyltrimethylammonium bromide (CTAB)/tetraethyl orthosilicate (TEOS) molar ratios of 0.07 and 0.16, HCl/TEOS molar ratios of 8 and 11, reaction temperatures of 35 and 45 ◦C and aging times of 12e24 h. The mesoporous SBA-3 samples obtained were characterized using small-angle X-ray powder diffraction (XRD), BET, FTIR and 29Si NMR-MAS, scanning electron microscopy (SEM) and transmission electron microscopy (TEM).
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    Pt-Pd-F/AI203catalyst applied in the HDT process.
    (Univesidsad Tecnológica Nacional., 2015) Balangero, Gerardo Simón; Falcón , Horacio; Beltramone , Andrea Raquel
    The inhibiting effect of basic and non-basic nitrogen compounds on the hydrogenation of polyaromatic compounds and on the hydrodesulphurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6DMDBT), has been investigated on Pt-Pd-F/Al2O3 and compared with a commercial NiMo hydrotreating catalyst. Langmuir-Hinshelwood type rate equations were used to describe the reaction kinetics accurately with physically meaningful and well identified parameter values. Model parameters were tuned by fitting experimental data obtained in a continuous flow reactor at 345°C, 1000 psi pressure and different contact times. Pt-Pd-F/Al2O3 was more active than NiMo catalyst and conversion remained constant during 24 h of TOS. The model was able to correctly interpret all the experimental data. Parameter estimation results showed that phenanthrene and naphthalene inhibited the tetralin hydrogenation rate, whereas naphthalene and tetralin had no appreciable effect on the rate of phenanthrene conversion. This inhibition could be explained by the competitive adsorption and was described in the kinetic model by adsorption terms obtained from the multicomponent experiments. The inhibiting effect of different nitrogen compounds on the polyaromatic hydrogenation was determined. The following nitrogen compounds were investigated in this study: quinoline, 1,2,3,4-tetrahydroquinoline, indole, and indoline. The degree of inhibition was expressed in terms of an apparent adsorption constant derived from the kinetics.The inhibiting effect on the HDS of DBT and 4,6 DBT followed the same trend