UTN- FRC -Producción Académica de Investigación y Desarrollo
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Item Vanadium and titanium oxide supported on mesoporous CMK-3 as new catalysts for oxidative desulfurization.(Univesidsad Tecnológica Nacional., 2016) Rivoira , Lorena Paola; Juárez , Juliana María; Falcón , Horacio; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaVanadium supported-CMK-3 catalysts with vanadium loading of 1–7 wt.% were studied in the oxidative desulfurization (ODS) of dibenzothiophene as a model sulfur compound. The activity was compared with titanium supported-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 TPR. The dispersion and the nature of the vanadium species depend on the V loading, so does the catalyst activity. Vanadium supported-CMK-3 with 7 wt.% of vanadium loading was the most active catalyst for ODS of DBT using hydrogen peroxide (H2O2) as oxidant and acetonitrile as solvent. 100% of DBT elimination was attained at short time in mild conditions. Carbon ordered mesoporous CMK-3 with high surface area and high pore volume promotes a very good anchorage of metallic oxides in the carbons framework reaching high active sites distribution and more stable nanoclusters. The reusability of the catalyst indicates that V-CMK-3 is a potential catalyst for the ODS of dibenzothiopheneItem Sulfur elimination by oxidative desulfurization with titanium-modified SBA-16.(Univesidsad Tecnológica Nacional., 2015) Rivoira , Lorena Paola; Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Ponte , María Virginia; Martínez , María Laura; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Martínez , María Laura; Ponte , María Virginia; Ledesma , Brenda Cecilia; Vallés , Verónica AlejandraTiO2-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. Pure TiO2 was used as reference. The titania-based catalysts were characterized by chemical analysis, XRD, EDX and TEM. The titanium state as tetrahedral (in Ti-SBA-16 sample) or octahedral (in TiO2/SBA-16 sample) coordination surrounding in the silicate matrix was determined by XPS, UV–vis DRS, FTIR, Raman and XANES. 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). In addition, we carried out a kinetic study and the activation energy was determined. 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.Item Sulfur elimination by ODSwith titanium-modified SBA-16.(Univesidsad Tecnológica Nacional., 2015) Rivoira , Lorena Paola; Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Martínez , María Laura; Anunziata , Oscar Alfredo; Beltramone, Andrea RaquelOver 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 activityItem ODS of dibenzothiopene with titanium-modified SBA-16.(Univesidsad Tecnológica Nacional., 2015) Rivoira , Lorena Paola; Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Martínez , María Laura; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Martínez , María LauraOver 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 attrac tive properties, including lower temperature and pressure conditions and lower operating cost [1-3] than conventional hydrodesulfurization (HDS) process. Oxidation of organosulfur com pounds 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, diben zothiophene 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 sup port in hydrotreating processes [7]. In this work, we describe the preparation and characteriza tion 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 tempe rature, nature of the substrate and reuse of catalysts)Item Vanadium oxide supported on mesoporous SBA-15 modified with AI and Ga as a highly active catalyst in the ODS of DBT.(Univesidsad Tecnológica Nacional., 2017) Rivoira , Lorena Paola; Martínez , María Laura; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar AlfredoVanadium pentoxide supported on mesoporous SBA-15 catalysts with different vanadium loadings were studied in the oxidative desulfurization (ODS) of dibenzothiophene as a model sulfur compound. 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 pentoxide crystallites are responsible for the high activity in the sulfur removal. The high dispersion depends on the vanadium loading and on the nature of the support. The more acidic support allowed better dispersion of the vanadium species. The Ga modified support with an intermediate V/Si ratio of 1/30 was the most active catalyst for ODS of DBT, using hydrogen peroxide (H2O2) as oxidant and acetonitrile as solvent. 100% of DBT elimination was attained at aItem Titania-modifed SBA-16 applied to oxidative desulfuration of DBT(2014) Rivoira, Lorena Paola; Vallés, Verónica; Ledesma, Brenda; Martínez, María Laura; Anunziata, Oscar Alfredo; Beltramone, Andrea RaquelRecent results show that Ti-containing molecular sieves exhibit good catalytic reactivity in the oxidation of sulfide, mercaptan, thiophene and derivatives [1]. In this work, we describe the preparation and characterization of new mesoporous catalytic materials based on Ti-containing SBA-16. The aim of the present work is to study the effect of the preparation method of titania-modified SBA-16 (characteristics of the active species Ti and/or TiO2) on the performance in the ODS of DBT with H2O2 and acetonitrile as solvent at mild conditions.