UTN- FRC -Producción Académica de Investigación y Desarrollo
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Item Experimental desing optimization of the ODS of DBT using vanadium oxide supported on mesoporous Ga-SBA-15.(Universidad Tecnológica Nacional Regional Córdoba., 2020) Rivoira, Lorena Paola; Cussa, jorgelina; Vallés, Verónica Alejandra; Martínez, María Laura; Beltramone, Andrea RaquelExperiment design-response surface methodology is applied in this work to model and optimize the oxidation of dibenzothiophene (DBT) using VOx-Ga SBA-15 catalyst. The analyzed variables are the influence of the nature of the catalyst (V and Ga loading), the substrate/catalyst mass ratio (g DBT/g of catalyst) and the oxidant/substrate molar ratio (H2O2/DBT). The response analyzed is conversion of DBT at 15 min of reaction time. A set of re- sponse surfaces were obtained applying the Box-Behnken Design. Based on statistical methodology it was pos- sible to find the best arrangement between the amounts of the gallium heteroatom and the vanadium active species. 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 between H2O2/DBT was 5. Gallium incorporation as heteroatom in tetrahedral position allowed the better anchorage of the active species of vanadium, generating a very well dispersed catalyst. The optimized catalyst minimized the mass transfer limitation and moreover, was active after several recycles. The best catalyst was likewise very active for the oxidation of the most refractory sulfur compounds as benzothiophene and 4,6-dimetyldi- benzothiopene.Item Mesoporous materials funtionalized with noble metals for bio-oil treatment.(Universidad Tecnológica Nacional Regional Córdoba., 2017) Rivoira , Lorena Paola; Martínez , María Laura; Beltramone, Andrea Raquel; Beltramone, Andrea Raquel; Martínez , María LauraBio-oil obtained by pyrolysis of biomass can be consider as a renewable petroleum alternative. Liquid fuel 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.Item HDT del modelo de alimentación diesel sobre catalizadores Zr-SBA-15 modificados con Ir.(Universidad Tecnológica Nacional Regional Córdoba., 2019) Vallés , Verónica Alejandra; Yanika , Sa-ngasaeng; Martínez , María Laura; Siriporn, Jongpatiwut; Beltramone, Andrea Raquel; Beltramone, Andrea RaquelCatalizadores de iridio con diferentes soportes de SBA-15 modificados con circonio se probaron en el HDT de tetralin y los compuestos típicos de azufre presentes en la alimentación de diesel. Los soportes se sintetizaron mediante el método sol-gel utilizando dos fuentes de circonio, cloruro de circonilo y propóxido de circonio (IV). El circonio se incorporó principalmente como especies tetraédricas de Zr+4 . El NH3-TPD de los catalizadores mostró una mayor acidez cuando están presentes las especies tetraédricas de Zr+ 4 . Entre los catalizadores preparados, el catalizador sintetizado utilizando propóxido de circonio y ácido láctico presentó la dispersión más alta y el tamaño de cluster más bajo. En consecuencia, este fue el catalizador más activo para la hidrogenación de tetralina y la HDS de dibenzotiofeno (DBT) y 4,6-dimetildibenzotiofeno (4,6-DMDBT). La presencia de Zr+4 tuvo un efecto notable en la capacidad de dispersión de las partículas de Ir. Además, la presencia de acidez moderada en este material proporciona el mejor catalizador para HDS en las condiciones estudiadas, lo que hace que sea un catalizador potencial para la reacción de HDT en condiciones suavesItem Catalizadores bimetálicos Platino/Iridio sobre soportes mesoporosos aplicados en la hidrogenación de HMF para la obtención de DMF.(Universidad Tecnológica Nacional Regional Córdoba., 2019) Ledesma , Brenda Cecilia; Juárez , Juliana María; Mazario, Jaime; Domine, Marcelo; Beltramone, Andrea Raquel; Beltramone, Andrea Raquel; Juárez , Juliana MaríaLa transformación catalítica de 5-hidroximetilfurfural (HMF) para producir 2,5-dimetilfurano (DMF) se estudió sobre catalizadores bimetálicos (PtIr) y monometálicos (Pt) soportados en materiales mesoporosos CMK-3 y SBA-15. La temperatura y presión óptimas para la producción máxima de DMF fueron 120 ° y 15 atm. Los aumentos de temperatura y presión disminuyeron la selectividad a DMF. Los catalizadores se caracterizaron ampliamente por XRD, N2-isotermas, XPS, TPR, TEM y NH3-TPD. Los sitios activos de la aleación PtIr fueron muy activos y selectivos hacia la formación de la DMF deseada. El catalizador PtIr-CMK-3 mostró una excelente actividad y selectividad.Item Novel and simple one-pot method for the synthesis of TiO2 modified-CMK-3 applied in oxidative desulfurization of refractory organosulfur compounds(Elsevier, 2018) Rivoira, Lorena Paola; Ledesma, Brenda Cecilia; Juárez, Juliana María; Beltramone, Andrea RaquelTi-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.Item Tetralin hydrogenation and ring opening of decalin over Ir-Pt-SBA-15(CICat, 2014) Vallés, Verónica Alejandra; Rivoira, Lorena Paola; Ledesma, Brenda Cecilia; Cussa, Jorgelina; Anunziata, Oscar Alfredo; Beltramone, Andrea RaquelA series of Ir and Pt modified SBA-15 were prepared by the consecutive wet impregnation method, with different content of each metal. The final catalysts were characterized by XRD, TEM and H2 chemisorption to study the effect of content of metal on the dispersion of iridium/platinum. The catalysts synthesized with similar percentage of both metals showed the best activity measured in tetralin hydrogenation and ring opening of decalin at mild conditions.Item Novel hybrid Ga-SBA-3 nanostructured material: Synthesis, Characterization and Applications(., 2018) Martínez, María Laura; Gómez Costa , Marcos Bruno; Beltramone, Andrea Raquel; Anunziata, Oscar AlfredoIn this work we study the incorporation of gallium in the structure of the SBA-3 mesoporous material, with the purpose of modifying the intrinsic acidity of the material using pyridine in order to determine the acidic sites that this material possesses. In addition, studies of adsorption / desorption of aniline and its subsequent polymerization on the mesoporous Ga-SBA-3, that gives the unique hybrids compound, with conductive characteristics similar to those of an inorganic semiconductor. Si-SBA-3 was prepared using CTABr and TEOS, as surfactant and Si source respectively. To obtain Ga-SBA-3 post-synthesis incorporation was employed. Ga-SBA-3 were dehydrated at 400 ° C under vacuum and then were exposed to vapors of pyridine / liquid aniline depending on the studies to be performed (pyridine to determine the acid sites of the material and aniline for subsequent polymerization) at vacumm. The in-situ polymerization of aniline was carried out to produce PANI/Ga-SBA-3. The final PANI/Ga-SBA-3 material was characterized by XRD, ICP, SEM-EDX, FTIR, BET. Direct current electrical conductivity measurements were performed using pellets and a four-probe technique, improving the contacts with a gold layer. Higher amount of polyaniline in conductive emeraldine salt form was found in PANI/Ga-SBA-3 composite, with respect to other composites reported in the literature. At room temperature (273 K), the electrical conductivity of PANI/Ga-SBA-3 was 2.5x10-3 S/cm, higher than its of Al-SBA-3 and Al-MCM- 41 homologs. To explain the conductivity of the composite (nanowire of PANI within Ga-SBA-3), we must consider the configuration of the nanostructured material and the type of PANI anchoring.Item Nanotubos de carbono de pared múltiple obtenidos con materila mesoporoso decorado con cerio-circonio(Universidad Tecnológica Nacional. Facultad Regional Córdoba, 2019) Rodríguez, Miguel Ángel; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Martínez, María LauraEn este trabajo, se ha empleado Ce-Zr-SBA-15 directamente como catalizador para la síntesis de nanotubos de carbono (CNT) a través de deposición química de vapor (CVD). Además del óxido de cerio, contiene nanocristalitos de óxido de circonio, que actúan como catalizadores para nanoestructuras de carbono. El rendimiento catalítico de este material se evaluó para la descomposición de etanol a 900 ° C, con flujo N2. La caracterización estructural del catalizador resultante se realizó por medio de microscopía electrónica de barrido (SEM). El carbono descompuesto de etanol absoluto se difunde a través de la superficie del material nanoestructurado y precipita en estructuras de carbono denominados Nanotubos de pared múltiple, los mismos pudieron visualizarse mediante microscopia electrónica de Transmisión (TEM), mostrando diámetros de los nanotubos de carbono que van desde 15 a 25 nm.Item Novel and simple one-pot method for the synthesis of titanium modified-CMK-3 applied in oxidative desulfutization of refractor y organosulfur compounds(Sociedad Mexicana de Materiales / Materials Research Society, 2018) Rivoira, Lorena Paola; Ledesma, Brenda Cecilia; Beltramone, Andrea RaquelTi-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 reducing time, energy consumption and cost. Our primary aim in this work is to evaluate the ODS activity of the Ti-modified mesoporous carbon CMK-3, synthesized by the short time method, in order to achieve total removal of sulfur compounds from diesel fuel. The catalytic oxidation of the sulfur compound with hydrogen peroxide was carried out in a glass batch reactor, equipped with a magnetic stirrer, a thermometer and a condenser. In a typical run, the solid catalyst (60 mg) was suspended under stirring (750 rpm) in 20 mL of a solution of 500 ppm of S as DBT (or other) in acetonitrile. Then, appropriate amount of 30% aqueous H2O2 was added at constant temperature. The experiments were performed in a three-phase liquid-liquid-solid (L (oil) –L (solvent) –S (catalyst)) system, acetonitrile was used as solvent and dodecane as oil phase. Solution samples were recovered at various times. The products were analyzed by GC HP 5890 Series II with a HP-5 column and connected to FID and PFPD detectors, after filtration and eventually decantation step. The products were confirmed using a Shimadzu GCMS. 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 different methods in order to prepare catalysts to be tested in the oxidative desulfurization (ODS) of sulfur compounds. 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.Item Influence of Ti Incorporationto Bimetallic Mesoporous Carbon in the Production of 2,5-Dimethylfuran from Biomass Derivatives.(Universidad Tecnológica Nacional., 2021) Ledesma , Brenda Cecilia; Juárez , Juliana María; Domine , Marcelo; Beltramone, Andrea Raquel; Beltramone, Andrea Raquel; Juárez , Juliana MaríaMonometallic and bimetallic supported catalysts were developed to produce 2,5-dimethylfuran (DMF) trough hydrogenolysis of 5-(hydroxymethyl)furfural (HMF). Detailed physicochemical characterization was done to understand structure–activity correlation. Through a series of experiments and comparatives tests, the synergistic effect among Pt, Ir, and Ti incorporated in the support was investigated. Results revealed that using the titanium contained ordered mesoporous carbon, synthesized by a novel technique, high selectivity to DMF was achieved. In the case of the best catalyst PtIr-TiC, the good activity and excellent selectivity to the desired product DMF (98% yield) was related to the high hydrogenating capacity of the bimetal lic sites, the acid support characteristics and the high metal nanoparticles dispersion achieved on the mesoporous titanium modified carbon support.