Browsing by Author "Beltramone, Andrea R."
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Item 2,5-dimethylfuran production by biomass via 5-hydroxymethylfurfural over bimetallic catalyst(2020) Ledesma, Brenda C.; Juárez, Juliana M.; Mazzario, Jaime; Beltramone, Andrea R.; Domine, MarceloEn el presente trabajo se estudió la transformación catalítica de 5-hidroximetilfurfural (HMF) para producir 2,5-dimetilfurano (DMF) sobre catalizadores bimetálicos (PtIr) y monometálicos (Pt) soportados en materiales mesoporosos CMK-3 y SBA-15. Se estudiaron también la temperatura y presión óptimas para lograr la máxima producción de 2,5 DMF. Los catalizadores se caracterizaron ampliamente por XRD, isotermas de N2, XPS, TPR, TEM y NH3-TPD. En el estudio se observó que las partículas metálicas estaban bien reducidas y muy dispersas en la superficie del soporte debido a la gran área superficial y la distribución de poros del mismo. Los sitios de PtIr fueron muy activos y selectivos hacia la formación del 2,5 DMF. El catalizador PtIr-CMK- 3 mostró una excelente actividad, selectividad y estabilidad para ser aplicado en este proceso.Item Agro-industrial waste as a source of catalyst production.(2021) Ledesma, Brenda C.; Beltramone, Andrea R.This work deals with the bio-waste valorization approach for catalyst development, the use of products derived from biomass as raw material and the obtaining of biofuels. In this research, activated carbons were synthesized from the orange peel using different synthesis conditions. With the activated carbons obtained with the best structure and texture, PtIr bimetallic catalysts were prepared. Carbon activation was carried out through a chemical process with phosphoric acid as an activating agent, varying the acid concentration, the ratio substrate/activating agent and time of contact between them. The best support was obtained using a carbonization time of 1 h, the temperature of carbonization of 470oC, the phosphoric acid concentration of 50 wt.% and a BET area of 1429 m2/g. Subsequently, the metallic nanoparticles were deposited in the activated carbon to use the solid as a catalytic material for the hydrogenation of HMF to 2,5-DMF. The catalyst presented an excellent performance for biofuels generation.Item Bimetallic platinum/iridium modified mesoporous catalysts applied in the hydrogenation of hmf(2020) Juárez, Juliana M.; Beltramone, Andrea R.; Ledesma, Brenda C.The catalytic transformation of 5-hydroxymethylfurfural (HMF) to produce 2,5-dimethylfuran (DMF) was studied over bimetallic (PtIr) and monometallic (Pt) catalysts supported on CMK-3 and SBA-15 mesoporous materials. The optimum temperature and pressure for the maximum production of DMF were 120° and 15 atm. Increases in temperature and pressure decreased the selectivity to DMF. The catalysts were broadly characterized by XRD, N2-isotherms, XPS, TPR, TEM and NH3-TPD. It was found that the metal particles were well reduced and highly dispersed on the surface of the support of large surface area and narrow pore distribution. The PtIr alloy species active sites were very active and selective towards the formation of the desired DMF. PtIr-CMK-3 showed an excellent activity, selectivity and stability to be applied in this process.Item Biofuel production using ordered mesoporous carbons with modified carbonaceous structure(2021) Ledesma, Brenda C.; Beltramone, Andrea R.Monometallic and bimetallic supported catalysts were developed to produce 2,5-dimethylfuran (DMF) trough hydrogenolysis of 5-(hydroxymethyl)furfural (HMF). Detailed physicochemical characterization was done in order 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 bimetallic sites, the acid support characteristics and the high metal nanoparticles dispersion achieved on the mesoporous titanium modified carbon support.Item Hydrodeoxygenation of guaiacol over pt/ga-mesoporous catalysts(2020) Beltramone, Andrea R.; Martínez, María Laura; Rivoira, LorenaLa hidrodesoxigenación (HDO) de guayacol, utilizado como molécula modelo, ha sido estudiada en un reactor batch sobre catalizadores de platino soportado sobre SBA-15 a 12 atm de presión y diferentes temperaturas, utilizando dodecano como solvente de reacción. El catalizador fue modificado con galio, incorporándolo como heteroátomo en la red mesoporosa de silíceos, mediante síntesis directa con el objetivo de modificar la naturaleza del soporte, pretendiendo mejorar la actividad catalítica del material. La acidez moderada que genera la incorporación de galio mejora la distribución de las especies activas de platino. En base a los resultados obtenidos el catalizador más activo en la HDO de guaiacol a 12 atm y 200°C fue Pt-Ga-SBA-15, con un 95% de conversión de reactivo en menos de 1 h de reacción.Item Influence of ti incorporation to mesoporous carbon structure for 2,5 dmf production by biomass(2021) Beltramone, Andrea R.; Ledesma, Brenda C.; Juárez, Juliana M.Several metal an bimettallics catalysts were prepared in order to evaluate performance to produce 2,5- dimethylfuran (2,5-DMF) trough hydrogenolysis of 5-(hydroxymethyl) furfural (5-HMF). Detailed physico-chemical characterisation was done in order to understand structure-activity correlation. Through a series of experiments and comparison, the synergistic effect among Pt, Ir, and Ti was investigated. The results revealed that the titanium contained in the ordered mesoporous carbon promotes a synergistic effect between Pt-Ir and Ti; that plays an important role in improving selectivity to DMF for PtIr / TiC bimetallic catalystsItem Influencia del proceso de síntesis de materiales mesoporosos ácidos en la obtención de hmf a partir de fructosa(2020) Mayer, Sergio; Falcon, Horacio; Ribotta, Pablo; Perez, Susana; Campos Martin, Jose Miguel; Garcia Fierro, Jose Luis; Martínez, María Laura; Beltramone, Andrea R.Motivados por el agotamiento irreversible de los recursos fósiles, en la actualidad se realizan esfuer-zos en obtener moléculas orgánicas de valor agregado a partir de biomasa. El 5-hidroximetilfurfural (HMF) es, junto al furfural, uno de los productos químicos de fuentes renovables de mayor interés por su potencial empleo en la obtención de bioplásticos, biocombustibles, lubricantes y adhesivos basados en furanos. Aquí presentamos dos catalizadores sintetizados por dos vías de síntesis diferentes, ambos con la incorporación de especies oxidadas de Zr, los cuales fueron caracterizados por XRD de bajo y alto ángulo, XPS y TPD-NH3. Los análisis demuestran la obtención de mesoporosos con arreglo de poros homogéneo, la incorporación de especies de Zr en red y extra-red y la generación de una acidez superficial moderada. Se discuten las propiedades obtenidas en relación a la reacción de deshidratación de fructosa a HMF, su conversión y rendimiento. El material Zr-SBA-15, que incorpora Zr in situ, de-muestra tener la mayor actividad catalítica, convirtiendo un 61,7 % de la fructosa y generando HMF con un rendimiento del 51,9 % en 2 h de reacción a 150 °C en un arreglo catalizador – solución acuosa de fructosa al 30 % – metil-isobutil-cetona (MIKB):2-butanol 7:3 P/P.Item Influencia del proceso de síntesis de materiales mesoporosos ácidos en la obtención de HMF a partir de fructosa(2019) Beltramone, Andrea R.; Mayer, Sergio; Falcón, Horacio; Ribotta, Pablo; Pérez, Susana; Campos Martin, José Miguel; Garcia Fierro, josé Luis; Martínez, María LauraMotivados por el agotamiento irreversible de los recursos fósiles, en la actualidad se realizan esfuer-zos en obtener moléculas orgánicas de valor agregado a partir de biomasa. El 5-hidroximetilfurfural (HMF) es, junto al furfural, uno de los productos químicos de fuentes renovables de mayor interés por su potencial empleo en la obtención de bioplásticos, biocombustibles, lubricantes y adhesivos basados en furanos. Aquí presentamos dos catalizadores sintetizados por dos vías de síntesis diferentes, ambos con la incorporación de especies oxidadas de Zr, los cuales fueron caracterizados por XRD de bajo y alto ángulo, XPS y TPD-NH3. Los análisis demuestran la obtención de mesoporosos con arreglo de poros homogéneo, la incorporación de especies de Zr en red y extra-red y la generación de una acidez superficial moderada. Se discuten las propiedades obtenidas en relación a la reacción de deshidratación de fructosa a HMF, su conversión y rendimiento. El material Zr-SBA-15, que incorpora Zr in situ, de-muestra tener la mayor actividad catalítica, convirtiendo un 61,7 % de la fructosa y generando HMF con un rendimiento del 51,9 % en 2 h de reacción a 150 °C en un arreglo catalizador – solución acuosa de fructosa al 30 % – metil-isobutil-cetona (MIKB):2-butanol 7:3 P/P.Item Magnetic fe304@si02-pt and fe304@si02-pt@si02 structures for hdn of índole.(2020) Dinamarca, Robinson; Valles, Verónica A.; Ledesma, Brenda; Campos, Cristian; Pecchi, Gina; Beltramone, Andrea R.Se informa el efecto de una segunda cubierta porosa de SiO2 en la actividad y selectividad del catalizador Fe3O4@SiO2-Pt en la hidrodenitrogenación de indol. La doble estructura de Fe3O4@SiO2-Pt se preparó recubriendo nanopartículas de Fe3O4 con TEOS y una impregnación adicional de 1,0% en peso de Pt en la estructura de Fe3O4@SiO2 funcionalizada con (3-aminopropilo)trietoxisilano. La segunda cubierta porosa de SiO2, obtenida utilizando la plantilla CTAB, con una distribución de tamaño de poro estrecha y bien definida, cubrió el catalizador Fe3O4@SiO2-Pt. La caracterización completa por TEM, ICP-OES, XRD, isoterma de adsorción de N2 a 77 K y VSM de los catalizadores indica estructuras homogéneas core@shell con un nano tamaño controlado de Pt metálico. Se demostró un efecto significativo de la doble capa de SiO2 en el rendimiento catalítico tanto por una mayor actividad para eliminar el átomo de nitrógeno de la molécula de indol, presente en el combustible líquido modelo, como por la mejora de la estabilidad catalítica, lo cual se observa en la obtención de cuatro ciclos de reacción consecutivos con solo una ligera disminución en la conversión.Item New catalyst source applied in biofuel manufacturing(2021) Ledesma, Brenda C.; Gómez Costa, Marcos B.; Beltramone, Andrea R.; Rivoira, Lorena P.A clean energy revolution is taking place all over the world in pursuit of replacing oil. This work stands out an environmental point of view by proposing biomass wastes from different industrial areas to produce not only a biofuel but also as raw material to synthetize the catalyst involved in the HDO reaction. In this way the process ceases to rely on the antiquated and obsolete linear economy where products, services, wastes, materials, water and energy have a beginning and an end to become a process with greater tendency to the modern circular economy, closely related to the idea of sustainability. Products, materials and resources are expected to last as long as possible while minimizing waste as much as possible too. Agricultural and forestry waste are available everywhere being a low cost raw material and it is possible to provide added value to the organic wastes of small and medium size enterprises. The hydrodeoxygenation (HDO) of guaiacol has been performed in a batch reactor under 12 atm of H2 and different temperatures over activated carbon synthetized from orange peel discarded from juice industry. Carbon activation was carried out through a chemical process with phosphoric acid as an activating agent, varying the acid concentration, the ratio substrate/activating agent and time of contact between them. The best support was obtained using carbonization time of 1 h, temperature of carbonization of 470oC, phosphoric acid concentration of 50 wt.% and with BET area of 1429 m2/g. Subsequently, the metallic nanoparticles were deposited in the activated carbon to use the solid as a catalytic material for the hydrodeoxygenation of guaiacol. The catalytic material was modified with metallic nanoparticles of Pt. The catalysts were characterized by means of X-ray diffraction, N2 isotherms, XPS, SEM and TEM. Good structure, narrow pore size distribution and high platinum dispersion were achieved in the synthesized catalysts. The objective of this investigation is the evaluation of the catalytic activity and to compare it with SBA-15 support studied previously. The catalyst presented excellent performance for biofuels generation.Item New efficient syntheses of nanostructured mesoporous catalysts to be applied to catalytic hydrotreatment(2021) Valles, Veronica; Beltramone, Andrea R.The presence of polyaromatic and cyclic compounds in diesel has a negative effect on the environment and reduces the quality of diesel, in addition to lowering the cetane number, which indicates its ease of ignition. Hydrotreating is one of the most efficient methods for the removal of N and S from refinery streams, as well as for the saturation of alkenes and aromatics. [1–4]. Mesoporous silica materials are synthesized by synergistic self-assembly between surfactant and silica species to form composites. [5,6]. Tetraethylorthosilicate (TEOS) is generally used as a source of Si, which is very efficient, but has a high cost. Another important variable in the search for catalysts that can be thought of to be replicated on an industrial scale is the synthesis time. In the present work, catalysts with alternative sources of Si were developed with the aim of reducing the cost of the synthesis of mesoporous supports. Modifications in the synthesis steps were also established to reduce the synthesis times. A series of syntheses of SBA-15 were carried out using silica gel and sodium silicate as an Si source, as an alternative to Tetraethylorthosilicate. Syntheses were also generated by varying the aging stages, with the use of a self-generated pressure Teflon reactor, trying to reduce the synthesis times. These mesoporous supports were modified with Al and impregnated with Ir, Pt and Pd. The catalysts were characterized by XRD, FTIR, NMR, TPR and N2 adsorption- desorption isotherms. The catalytic activity was measured in a 4563Parr reactor, at 250°C, 15 atm of pressure of hydrogen and 360 rpm for tetralin hydrogenation (feed consisted in 50 mL of 5% v/v of tetralin (98.5% FLUKA) in Dodecane).Item Revalorization of agro-industrial waste as a catalyst source for obtaining biofuels(2021) Ledesma, Brenda C.; Beltramone, Andrea R.This work deals with the bio-waste valorization approach for the catalyst development, the use of products derived biomass as raw material and the obtaining of biofuels. In this research activated carbons were synthesized the orange peel using different synthesis conditions. With the activated carbons obtained with the best structure and texture, PtIr bimetallic catalysts were prepared. Carbon activation was carried out through a chemical process with phosphoric acid as an activating agent, varying the acid concentration, the ratio substrate/activating agent and time of contact between them. The best support was obtained using carbonization time of 1 h, temperature of carbonization of 470oC, phosphoric acid concentration of 50 wt.% and with BET area of 1429 m2/g. Subsequently, the metallic nanoparticles were deposited in the activated carbon to use the solid as a catalytic material for the hydrogenation of HMF to 2,5-DMF.The catalyst presented excellent performance for biofuels generation.