UTN- FRC -Producción Académica de Investigación y Desarrollo
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Item Tetralin hydrogenation over Pt-Ir/SBA-15. optimization by experimental desing.(XXIV International material research congress, 2015) Vallés, Verónica; Ledesma, Brenda; Rivoira, Lorena; Cussa, Jorgelina; Anunziata, Oscar; Beltramone, AndreaThe 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 reaction 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 reactions. 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.Item Experimental desing optimization of the tetralin hydrogenation over Ptlr/SBA-15(International Symposium on Advances in Hydroprocessing of Oil Fractions, 2015) Valles, Verónica; Ledesma, Brenda; Rivoira, Lorena; Cussa, Jorgelina; Anunziata, Oscar; Beltramone, AndreaThe 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 reaction chemistry occurring in the gas oil hydrotreater. To find alternative processes, it is necessary 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 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 [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.Item Sulfur elimination by oxidative desulfurization with titanium-modified SBA-16(International Symposium on Advances in Hydroprocessing of Oil Fractions, 2015) Rivoira, Lorena; Vallés, Verónica; Ledesma, Brenda; Martínez, María Laura; Anunziata, Oscar; Beltramone, AndreaOver the past, oxidative desulfurization (ODS) has drawn considerable interest as a new alternative method for deep sulfur elimination from light oils. This can be attributed to its attractive properties, including lower temperature and pressure conditions and lower operating cost [1-3] than conventional hydrodesulfurization (HDS) process. Oxidation of organosulfur compounds results in the formation of sulfoxides/sulfones, highly polar and hence easily removed by both extraction into polar solvents or by adsorption. Due to their low reactivity, dibenzothiophene derivatives (DBTs) are the most refractory species to be eliminated from oils. Hence, the ODS process through which DBTs are converted to their corresponding sulfones involves great interest at present [4-6]. We recently reported a good performance of this support in hydrotreating processes [7]. In this work, we describe the preparation and characterization of new mesoporous catalytic materials based on Ti-containing SBA-16. We study here, the effect of the preparation method of titania-modified SBA-16 (characteristics of the active Ti and/or TiO2 species) and the effect of the different operation conditions in ODS of DBT under mild conditions in order to find the best performance. TiO2-modified mesoporous SBA16 and titanium-substituted mesoporous SBA-16 were developed and tested in the oxidative desulfurization (ODS) of dibenzothiophene prevailing in liquid fuel. We assessed the impact exerted on performance of different reaction variables, including (nature and amount of the active catalytic species, phase system, molar ratio of oxidant H2O2 and DBT, reaction temperature, nature of the substrate and reuse of catalysts).Item Síntesis y caracterización de composites nanoestructurados de polipirroI/SBA-3 Y polipirroI/AISBA-3(Universidad Tecnológica Nacional., 2011) Martínez , María; Luna D´Amicis , Froilán; Gómez costa , Marcos; Beltramone, Andrea; Anunziata, OscarNuevos composites polipirrol/SBA-3 y polipirrol/Na-AlSBA-3 fueron sintetizados. El pirrol fue adsorbido en fase gaseosa sobre la superficie de los poros de los materiales mesoporosos SBA-3 y Na-AlSBA-3, para luego ser polimerizado in-situ. Para la polimerización se colocó los materiales, que contenían pirrol adsorbido, en solución acuosa de cloruro férrico o persulfato de amonio, a temperaturas de 0 ºC y 25 ºC. Los composites obtenidos son analizados mediante FTIR, XRD y análisis de área mediante el método BET. De ambos materiales, la SBA-3 presenta bandas de adsorción en el infrarrojo más definidas de pirrol adsorbido que el material Na-AlSBA-3. En correspondencia con estos resultados el material polipirrol/SBA-3 muestra bandas más definidas de polipirrol que el composite polipirrol/NaAlSBA-3. Las reacciones realizadas a 0 ºC resultaron en polimerizaciones incompletas según lo mostrado por los espectros de FTIR mientras que a 25 ºC la polimerización fue exitosa. De ambos oxidantes el que mejores resultados presentó fue el cloruro férrico. Los patrones de XRD dan indicios de RESUMEN Introducción espectros de FTIR mientras que a 25 C la polimerización fue exitosa. De ambos oxidantes el que mejores resultados presentó fue el cloruro férrico. Los patrones de XRD dan indicios de que la nanoestructura de los materiales mesoporosos se mantiene luego de la polimerización in-situ. Estos materiales están formados por nanoalambres de polipirrol contenidos en el interior de los canales de estos hospedajes teniendo numerosas aplicaciones en el campo de la nanotecnologíaItem Hidrodenitrogenación de quinolina sobre Ir/SBA-16 modificada con titanio.(Universidad Nacional de San Luis, 2013) Ledesma, Brenda; Valles, Verónica; Rivoira, Lorena; Ponte, María; Martínez, María; Anunziata, Oscar; Beltramone, AndreaEn este trabajo se estudió la actividad catalítica de Ti-SBA-16 y TiO2/SBA-16 modificado con 1 % de Ir, en la hidrodenitrogenación de quinolina, en condiciones suaves de reacción utilizando un reactor Parr a 250°C y 15 atm. Se investigó el efecto del agregado de titanio, que modificando el soporte, influyó sobre la dispersión y tamaño de los cluster de iridio.Item SBA-3 obtenida a través de síntesis química suave: influencia del parámetro de temperatura.(Univesidsad Tecnológica Nacional, 2013) Ponte , María; Ledesma, Brenda; Valles, Verónica; Martínez, María; Beltramone, AndreaLa química suave es un punto de partida atractivo para el desarrollo de materiales nanoestructurados (mesoscópicos), en vista de las condiciones de sintesis tipicas: bajas temperaturas; coexistencia de los inorgánicos, orgánicos, una amplia opción de precursores (monómeros o especie condenseda); y posibilidades de formación controlada (por ej, polvos, geles, películas, etc.). La exploración en este campo viene creciendo constantemente y entre los materiales obtenidos por mediode este tipo de sintesis son los Materiales Mesoparosos, tales como SBAs, con nanoporos uniformes y una elevada área superficial específica (1], debido a sus potenciales aplicaciones como catalizadores, tamices moleculares y composites huésped hospedaje [2]. La finalidad de esta investigación es la obtención de materiales del tipo SBA-3 variando los distintos parámetros de síntesis entre ellas la temperatura. Estos silicatos son caracterizados por Difracción de Rayos X, como puede observarse en la figura 1, en este difractograma se puede observar los indices de Miller correspondientes a los planos (100), (110) y (200) indicando una estructura porosa del tipo hexagonal. Los parámetros de red, 1 200 ao, obtenidos para dichas estructuras van de 3.3 a 3.79 nm. También se les efectuo Espectroscopia de Infrarrojo con Transformada de Fourier. Los espectros infrarrojos obtenidos mostraron las bandas características de los enlaces en este tipo de materiales. Se observan la presencia de los stretching asimétricos T-O (T=Si) debido a vibraciones TO, tetraédricas externo a 1232 cmi' e interno a 1086 cmil y el correspondiente al bending Me-O-Si (Me= Si) tetraédrico a 968 cm [3,4]. Se pudo observar que la temperatura de síntesis en la que se obtienen mejores resultados es la de 30 °C, así mismo a medida que nos alejamos de este valor ya sea en orden ascendente como descendente de temperatura se obtienen estructuras con un menor ordenamiento hexagonal. Referencias [1] C. T. Kresge, M.E. Leanowicz, W. Roth, J.C. Vartulli, J. Beck, Nature 359 (1992) 710. [2] O. A. Anunziata, A. Beltramone, M. L. Martinez, L. López Belon. J. of Colloid interf. science 315 (2007) 184-190. [3] O. A. Anunziata, M. B. Gómez Costa, M.L. Martinez, Catalysis Today 133-135 (2008) 897-905. [4] O. A. Anunziata, M. Gómez, R. Sanchez. J, of Colloid Interf. Science, 292 (2) (2005) 509-516.Item Encapsulation of PANI nanowires into AI-SBA-3 and AI-SBA-16 nanoporous materials.(Univesidsad Tecnológica Nacional, 2011) Gómez Costa, Marcos; Martínez, María; Luna D´Amicis , Froilán; Beltramone, Andrea; Anunziata, OscarThe encapsulation of nanosized conducting polymer filaments such as polyaniline, into the channels of mesoporous aluminosilicate hosts (i.e. SBA-3, SBA-16), would permit the feasibility of using mesoporous materials in nanometer-scale for electronic devices. [1, 2]. The goal of this work is to synthesize PANI/Na-AlSBA-3 and PANI/Na-AlSBA-16 composites (with PANI inside of the nanoporous channels of materials), with electrical conducting or semiconducting properties, using in situ polymerization techniques in order to contribute to the understanding of the aniline adsorption mode onto the host and its influence on the final composite material. It could be possible modify conductive properties of composite, varying the substituents of the aromatic ring, the host structure and the anchored sites to adsorb aniline, and the amount of PANI in the hosts.Item Hidrodenitrogenación de quinolina sobre Ir/Ti02/SBA-16(Univesidsad Tecnológica Nacional, 2013) Ledesma , Brenda; Valles , Verónica; Ponte, María; Martínez, María; Beltramone, AndreaCatalizadores nanocristalinos de TiOa soportados sobre SBA-16 preparados por una nueva via de sintesis. (hidrolisis del Ti-acetilacetonato) por el metodo de sol-gel previene la transformación de anatase a la fase del rutilo y el crecimiento descontrolado del cristal. La mesoestructura le confiere una estabilidad térmica relativamente alta y el diámetro apropiado de poro permitiria controlar el tamaño de las particulas obtenidas de anatase dentro de los canales. y lograr una mejor dispersión del metal noble, accesibles a moléculas para su transformación Los datos indican el potencial interes de este material como catalizador para HDN, debido a a presencia de un area altamente activa de los nanoparticulas de TiCa dentro del materia mesoporoso SEA.Item Hydrogenation of tetralin over Ir-containing mesoporous catalysts.(Univesidsad Tecnológica Nacional, 2012) Ponte, María; Valles, Verónica; Anunziata, Oscar; Beltramone, AndreaIn this work we study the catalytic properties of 1 wt% Ir-containing mesoporous materials 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. We described the preparation of new nanostructured catalytic materials containing highly and homogeneously dispersed particles of Ir 0 after reduction, and investigate their activity for hydrogenation of aromatic compounds, using tetralin as a model substrate. The metal particle size of supported metal catalysts is an important factor affecting the catalytic behavior and the support, in particular, the pore structure, can affect the metal dispersion. The Ir/SBA 3 catalyst synthesized by us had higher activity than Ir/Al-SBA-3 and Ir-MCM-41, measured in tetralin hydrogenation at mild conditions. The experimental data were quantitatively represented by a modified Langmuir-Hinshelwood type rate equation. The catalyst showed a good resistance to sulfur. The preliminary results show this material as a promising catalyst for HDS/HDN reactions.Item Optimization of NOx selective catalytic reduction in presence of iso-butane and 02 using Fecontaining ZSM-11 zeolites by multivariate analysis.(Univesidsad Tecnológica Nacional, 2012) Cussa, Jorgelina; Beltramone, Andrea; Anunziata, OscarThe nitrogen oxides reduction is a problem that the environmental catalysis still tries to solve. Thus, for this problematic, the processes can be grouped in three general lines of work: minimization of the production of NOx; direct decomposition of NO to N2 + O2, and selective catalytic reduction (SCR). Fe-ZSM-5 has in recent times received much attention in catalysis research because of its promising activity in the decomposition or selective reduction of nitrous oxide. Fe-ZSM-11 zeolites, prepared by novel sol-gel process with Fe2+ and/or Fe3+ as active sites incorporated by reproducible post-synthesis methods were obtained. We reported the relationship between the catalytic activity and the nature of the active sites [1]. The experiment design - response surface methodology is used in this work to optimize the NOx selective catalytic reduction to N2 using the above cited catalyst. The main objective is to define the response surfaces, finding the best combination of different parameters in order to optimize the process, for this reason, the experiments design methodology was applied reducing the operation costs, achieving efficiency and effectiveness in the process. The application of this methodology leads us to a better understanding of the influence of the different factors such as: number and strength of the acid sites, Fe2+/Fe3+ relation, [NO3*] and [NO2*] adsorbed intermediates, the concerted reaction mechanism proposed in the previous work, and the effect of the reaction temperature and their interactions. The statistic model applied in this work is a powerful tool to interpret the overall process from the multivariate parameters. The goal of the present work would be to identify the key-factors to optimizing the best operation conditions and catalysts characteristics, which are responsible for the enhanced performance of Fe-zeolites and thereby to corroborate with even better catalyst formulations. According to the statistic methodology applied, the best operation conditions and catalysts characteristics can be identified, allowing us to re-design the catalyst to enhance the NOx conversion and N2 and CO2 selectivity at optimum reaction temperature.