UTN- FRC -Producción Académica de Investigación y Desarrollo

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Subject: search.filters.subject.Direct synthesis

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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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    Short time synthesis of titania modified-CMK-3 carbon mesostructure as support for Ir-catalyst applied in catalytic hydrotreating
    (2020) Ledesma, Brenda Cecilia; Juárez, Juliana María; Beltramone, Andrea Raquel
    Ti-CMK-3 carbon mesoporous was prepared using a novel synthesis method. This new method avoids the hard template synthesis used commonly. The method developed here, allows to reduce time, energy consumptionand cost. Structural and textural characterization of the titanium modified-mesoporous carbonwas performed by N2 adsorption, XRD, UV–vis-DRS, 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 modi fied-mesoporous carbon was used as support of the iridium nanoparticles, in order to prepare a catalyst to be tested in model hydrotreating reactions. The catalyst obtained by wet impregnation with iridium acetylacetonate were characterized by ICP -AES, H2 chemisorption, TEM, XPS and FTIR of adsorbed pyridine. The high Ir dispersion and small particle size, along with the moderate Lewis acidity generated by the presence of titanium in the support, were responsible for the good performance and stability of the catalyst in the hydrogenation of tetralin in presence of nitrogen com - pounds. Main advantage of the present study is the reduction of time and cost in the synthesis of the new material and the applicability for HDT reactions.
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    HDT of the model diesel feed over Ir-modified Zr-SBA-15 catalysts
    (2018) Vallés, Verónica Alejandra; Yanika, Sa-ngasaeng; Martínez, María Laura; Siriporn, Jongpatiwut; Beltramone, Andrea Raquel
    Iridium catalyst using different zirconium modified-SBA-15 supports were tested in the HDT of tetralin and typical sulfur and nitrogen compounds present in diesel feed. The zirconium modified-SBA-15 supports were synthesized by sol-gel method using two sources of zirconium, zirconyl chloride and zirconium (IV) propoXide. Regarding XRD, N2 adsorption isotherms and TEM, we obtained better textural and structural properties using the alkoXide, especially when lactic acid was added in order to decrease the hydrolysis rate of zirconium propoXide. In addition, XPS and DRUV-Vis demonstrated that zirconium was incorporated mainly as tetrahedral Zr4+ species NH3-TPD showed that higher acidity is observed when tetrahedral Zr4+ species are present. Iridium dispersion was determined by TEM and H2-chemisorption and reducibility by XPS and TPR. Among the catalysts prepared, the catalyst synthesized using zirconium propoXide and lactic acid presented the highest dispersion, lowest cluster size and lowest reduction temperature. Consequently, this was the most active catalyst for the hydrogenation of tetralin, the HDN of indole and quinoline and the HDS of dibenzothiophene (DBT) and 4,6- dimethyldibenzothiophene (4,6-DMDBT). The presence of Zr+4 had a remarkable effect on the dispersion and reducibility capacity of the iridium actives species. In addition, the presence of moderate acidity in this material gives the best catalyst for HDN and HDS in the studied conditions. The inhibition effect of the sulfur and nitrogen compounds over tetralin hydrogenation was studied using individual feeds and a miXture feed. We observe that 4,6-DMDBT and quinoline were the most refractory compounds and they showed the highest inhibition effect. Tetralin hydrogenation was stronger inhibited when using the miXture feed compared with the individual feeds. This can be explained in terms of the competition between the different compounds that retard the rate of hydrogenation of tetralin. However, a high conversion of tetralin was achieved even when 300 ppm of S or N was