UTN- FRC -Producción Académica de Investigación y Desarrollo

Permanent URI for this communityhttp://48.217.138.120/handle/20.500.12272/1932

Browse

Has files: YesSubject: search.filters.subject.SBA-16

Search Results

Now showing 1 - 6 of 6
  • Thumbnail Image
    Item
    Sulfur elimination by ODSwith titanium-modified SBA-16.
    (Universidad Tecnológica Nacional., 2015) Rivoira , Lorena Paola; Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Martínez , María Laura; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel
    Over the past, oxidative desulfurization (ODS) has drawn considerable interest as a new alter-native 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 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. 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 SBA-16 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). We achieved 90% of S removal from a 0.2 wt.% dibenzothiophene solution at 60°C in less than 1 h of reaction. The best catalytic results are obtained with high exposed surface of nanometric TiO2 species of TiO2/SBA-16 sample. The activated catalyst is very active in ODS reaction and can be reused four times with no loss in activity
  • Thumbnail Image
    Item
    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.
  • Thumbnail Image
    Item
    Hidrodenitrogenación de quinolina sobre Ir/Ti02/SBA-16
    (Univesidsad Tecnológica Nacional, 2013) Ledesma , Brenda; Valles , Verónica; Ponte, María; Martínez, María; Beltramone, Andrea
    Catalizadores 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.
  • Thumbnail Image
    Item
    Hidrogenación de tetralin utilizando Ir/Ti02/SBA-16.
    (Federación Iberoamericana de Sociedades de Catálisis, 2012) Valles , Verónica; Ponte , María; Ledesma, Brenda; Anunziata, Oscar; Beltramone, Andrea
    Factores tales como, el efecto del soporte y la dispersión del metal, han sido estudiados en conexión con el proceso de HDT (hidrotratamiento catalítico) [1-2] y los resultados obtenidos sugieren que el Ir podría ser una especie catalítica activa para la transformación de aromáticos a compuestos saturados y eficiente para eliminar azufre y nitrógeno, como sitio activo o como promotor de los catalizadores convencionales. Por lo tanto el principal objetivo de este trabajo, que es desarrollar un catalizador en base a Ir/ soporte mesoporoso, modificado con TiO2 activo para la hidrogenación de tetralín y resistente a compuestos con azufre, en condiciones de reacción menos severas que las industriales utilizando un reactor batch. En este trabajo se estudió la actividad catalítica de Ir/TiO2/SBA-16 modificado con 1 % de Ir, en la hidrogenación de tetralin a decalin en presencia de 100 ppm de S como dibenzotiofeno, en un reactor Parr a 250°C y 15 atm.
  • Thumbnail Image
    Item
    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.
  • Thumbnail Image
    Item
    Inhibition of the hydrogenation of tetralin by nitrogen and sulfur compounds over Ir/SBA-16
    (2011) Balangero, Gerardo Simón; Martínez, María Laura; Gómez Costa, Marcos Bruno; Anunziata, Oscar Alfredo; Beltramone, Andrea Raquel
    In this work we study the catalytic properties of 5 wt.% Ir-containing SBA-16 catalysts (with and without aluminum as heteroatom), in the hydrogenation of tetralin to decalin, in the presence of 100 ppm of N as quinoline, indole and carbazole, and 100 ppm of S as dibenzothiophene and 4,6-dimethyl- dibenzothiophene at 250 ◦C and 15 atm of pressure of hydrogen, using a Parr reactor. Ir/SBA-16 and Ir/Al-SBA-16 were prepared by wetness impregnation using Iridium Acetylacetonate as source of Ir. The Ir/SBA-16 catalyst synthesized by us had high activity measured in tetralin hydrogenation at mild con- ditions. The experimental data was quantitatively represented by a modified Langmuir–Hinshelwood type rate equation, using the apparent adsorption constants calculated from the inhibition results for the individual compounds. The catalyst showed a good resistance to sulfur and nitrogen compounds. The inhibiting effect increased in the order: DBT < quinoline < 4,6-dimethyl-DBT < indole < carbazole. The inhibiting effect of the nitrogen/sulfur compounds was strong, but the activity was still higher than with commercial NiMo/alumina catalyst. We present in this contribution a successfully developed, high loaded and well dispersed Ir/SBA-16 catalysts, that have been shown to maintain a useful catalytic activity, even in the presence of relatively high amounts of sulfur compounds (up to 100 ppm, sulfur basis). Consequently, economically successful processes have evolved, based on this class of catalysts.