UTN -FRC -Producción Académica de Investigación y Desarrollo - Comunicaciones a Congreso
Permanent URI for this collectionhttp://48.217.138.120/handle/20.500.12272/2433
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Item Synthesis and characteristics of magnetite containing-cmk-3 and its application in hydrogen storage(2020) Juárez, Juliana M.; Venosta, Lisandro F.; Gómez Costa, Marcos B.; Anunziata, Oscar A.In this work, we report the synthesis and characterization of iron oxide nanoparticles (Magnetite) supported on CMK-3. The materials were characterized by XRD, SEM, TEM, XPS and magnetization studies. A large amount of the iron incorporated as iron oxide nanoparticles was in the magnetite phase. The incorporation of magnetite on the CMK-3 carbon surface significantly improved the hydrogen storage capacity (4.45 wt. % at 77 K and 10 bar) compared to the CMK-3 structure (2.20 wt% at 77 K and 10 bar). Magnetite nanoparticles play a key role in H2 adsorption.Item Direct synthesis and characterization of mesoporous carbon CMK-3 modified with zirconia applied in energy storage(2020) Venosta, Lisandro F.; Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.In this work, we report the synthesis and characterization of the nanostructured carbon material (CMK- 3) modified with zirconium oxide synthesized by a new direct synthesis technique. The aim of this new synthesis method is to avoid the use of inorganic siliceous template (SBA-15), which leads to a shorter and cheaper way to obtain mesoporous carbon, and at the same time incorporate into the framework Zirconium atoms. Zirconium oxide dispersed in carbon materials (Zr-CMK-3) were successfully synthesized and characterized by X-ray diffraction, textural properties, UV-Vis-DRS, XPS, and transmission electron microscopy analysis. This material is promising in the application of hydrogen adsorption for energy storage. Zr-CMK-3 material significantly improved H2 storage behavior (4.6% by weight at 77 K and 10 bar) compared to CMK-3 support. The synthesized material is promising in the absorption of hydrogen by weak bonding forces (physisorption). A hydrogen adsorption mechanism was proposed and the role of the Zr+4 cation in hydrogen absorption was discussed. The activity of the samples to the adsorption of hydrogen molecules is attributed to the improved dispersion of the zirconium oxide, as well as the appropriate use of support, which can probably disperse the zirconium on its large surface area, allowing a great dispersion of the zirconium. The Zr+4 cation is an active species to absorb and store hydrogen through a physisorption process and the carbon plays an important role in the dispersion and size of metal particles. A hydrogen storage mechanism on the active surface of the ZrO2 clusters was proposed. First layer of hydrogen molecules can react with the metal cation through a dihydrogen complex (Kubas interaction) [1]. The second layer of hydrogen molecules adsorbed around the metal oxide clusters is due to dipole-like interactions, this is because the metal particle induces dipole forces on the hydrogen molecule. The other layers could also interact by dipole forces; however, the interaction force decreases as the distance to the surface increases. The interaction of the induced dipole in a second layer adsorbs more hydrogen molecules because the strong interaction of the metal particles takes up dipole-induced forces on the hydrogen molecules. The upper layers could interact with the metal cation by dipole-induced bonding; however, the interaction force decreases as the distance to the surface increases. The procedure for this adsorption is still under investigation and optimization. The hydrogen storage behavior in Zr-CMK-3 can be optimized by controlling the size of the metal particles, the dispersion and the nature of the support.Item Síntesis directa del carbón mesoporoso ordenado cmk-3 modificado con circonio aplicado en almacenamiento de energía(2020) Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.; Venosta, Lisandro F.En este trabajo, informamos la síntesis y caracterización del material de carbono nanoestructurado (CMK-3) modificado con óxido de circonio sintetizado por una nueva técnica de síntesis directa. Este material es prometedor en la aplicación de adsorción de hidrógeno para el almacenamiento de energía. Los materiales con óxido de circonio (Zr-CMK-3) se sintetizaron con éxito y se caracterizaron por difracción de rayos X, propiedades texturales, UV-Vis-DRS, XPS y análisis de microscopía electrónica de transmisión. El material Zr-CMK-3 mejoró significativamente el comportamiento de almacenamiento de H2 (4,6% en peso a 77 K y 10 bar) en comparación con el soporte CMK-3. El material sintetizado es prometedor en la absorción de hidrógeno por fuerzas de enlace débiles (fisisorción). Se propuso un mecanismo de adsorción de hidrógeno y se discutió el rol de catión Zr+4 en la absorción de hidrógeno.Item Síntesis, caracterización y aplicación del nanomaterial lp-sba-15 en la liberación controlada de ketorolac trometamina(2020) Juárez, Juliana M.; Gómez Costa, Marcos B.; Cussa, JorgelinaLos sistemas controlados de administración de fármacos pueden mantener la concentración de medicamentos en los sitios exactos del cuerpo dentro del rango óptimo y por debajo del umbral de toxicidad, mejorando la eficacia terapéutica y reduciendo la toxicidad. El material LP-SBA-15 es un nuevo huésped prometedor para los sistemas de administración de fármacos debido a su alta biocompatibilidad, biodegradabilidad in vivo y baja toxicidad. Se sintetizó el composite ketorolac-trometamina/LP-SBA-15. La síntesis del material y la carga de ketorolac-trometamina en los poros LP-SBA-15 fue exitosa, como lo demuestran los análisis XRD, FTIR, TGA, TEM y análisis morfologicos. Obtuvimos resultados prometedores para la liberación controlada de fármacos utilizando el nuevo material. La aplicación de estos materiales en la liberación de KETO es innovadora, logrando una alta tasa de liberación inicial y luego manteniendo una liberación más lenta. Esto permite mantener la concentración del fármaco dentro del rango de eficacia terapéutica, siendo altamente aplicable para el tratamiento de enfermedades que necesitan una respuesta rápida.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 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 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 Preparation, characterization and mathematical modeling of keterolac release conteined in lpsba-15 host(2021) Cussa, Jorgelina; Juárez, Juliana M.; Gómez Costa, Marcos B.; Anunziata, Oscar A.Drug-controlled release systems can keep the level of drugs in precise doses in the body above the optimal level and with low toxicity. We propose the LP-SBA-15 nanomaterial as a promising new host for drug delivery systems because of its high biocompatibility, in vivo biodegradability, and low toxicity. Ketorolac-LP-SBA-15 was prepared and characterized by XRD, FTIR, UV-Vis DRS, TEM, and texture analysis, determining the adsorption capacity and its release, achieving the required therapeutic efficacy. The host shows ordered mesoporous nanochannels with a diameter of 11-12 nm, maintaining the structure with the incorporation of Keto. The mechanism of drug release the LP-SBA-15 host was evaluated. Different mathematical models were used to adjust the experimental data, being the Ritger-Peppas model followed by the Weibull model the best ones. In this work, we show a promising drug storage material for effective encapsulation and controlled release of KETO, achieving the required therapeutic efficacy. Studies indicate that KETO was adsorbed on the channel surface of LP-SBA-15 without affecting the structure or chemical composition of KETO. Controlled drug delivery systems can achieve precise delivery at the time and place of destination, keeping the concentration of the drug at points in the body within the optimal range and below the toxicity threshold. The study also demonstrates the storage capacity and release properties of LPSBA- 15 containing KETO. The release of KETO contained in LP-SBA-15 can offer a significant improvement in the controlled release of the drug and the analgesic and anti-inflammatory effects, positively influenced, by the links formed between the host and drug molecules and by diffusion through the host porosity. The promising results we obtained for the release of the drug thoroughly using the new material, reaching a rapid initial release rate, and maintaining a constant rate afterward, allow us to maintain the concentration of the drug in the therapeutic efficacy range, applying it largely to the treatment of diseases that require a rapid response.Item Hydrogen storage on a novel nanostructured carbón material modified with zirconia(2021) Juárez, Juliana M.; Gómez Costa, Marcos B.; Anunziata, Oscar A.; Venosta, Lisandro F.In this work, we report the synthesis and characterization of zirconium oxide supported in nanostructured carbon material synthesized by a new direct synthesis technique. The goal of this new method is to avoid the use of inorganic siliceous template (SBA-15), which leads to a shorter and cheaper way to obtain mesoporous carbon, and at the same time incorporate into the framework Zirconium atoms. The material with zirconium oxide (Zr-CMK-3) was successfully synthesized and characterized by Xray diffraction, SEM, RAMAN and textural properties, UV-Vis-DRS, X-ray photoelectron spectroscopy and transmission electron microscopy analyses. Zr-CMK-3 improved significantly the H2 storage behavior (4.6 wt% at 77 K and 10 bar) compared with CMK-3. The synthesized material is promising for hydrogen uptake by means of weak bonding (physisorption). The activity of the samples to the adsorption of hydrogen molecules is attributed to the improved dispersion of the zirconium oxide, as well as the appropriate use of support, which can probably disperse the zirconium on its large surface area, allowing a great dispersion of the zirconium. The Zr+4 cation is an active species to absorb and store hydrogen through a physisorption process and the carbon plays an important role in the dispersion and size of metal particles. A hydrogen storage mechanism on the active surface of the ZrO2 clusters was proposed. First layer of hydrogen molecules can react with the metal cation through a dihydrogen complex (Kubas interaction). The second layer of hydrogen molecules adsorbed around the metal oxide clusters is due to dipole-like interactions, this is because the metal particle induces dipole forces on the hydrogen molecule. The other layers could also interact by dipole forces; however, the interaction force decreases as the distance to the surface increases. The upper layers could interact with the metal cation by dipole-induced bonding; however, the interaction force decreases as the distance to the surface increases.Item New method for Ccmk-3 synthesis modified with zr applied in h2 storage(2021) Juárez, Juliana M.; Gómez Costa, Marcos B.; Venosta, Lisandro F.; Anunziata, Oscar A.In this work we develop a novel direct synthesis method of modified CMK-3 with zirconium oxide. This modification occurs during the synthesis process. Our assessment includes a one-step synthesis of nanostructured mesoporous carbon modified with zirconium oxide, the characterization of the resulting material by XRD, N2 adsorption, XPS, UV-Vis, TEM, SEM and Raman. We show the enhancement of the storage capacity of the composite material, compared to bare CMK-3.