UTN- FRC -Producción Académica de Investigación y Desarrollo

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Author: search.filters.author.Juárez , Juliana María

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    Novel preparation of CMK-3 nanostructured material modified with titania applied in hydrogen uptake and storage.
    (Universidad Tecnológica Nacional., 2017) Juárez , Juliana María; Ledesma , Brenda Cecilia; Gómez Costa, Marcos Bruno; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Ledesma , Brenda Cecilia
    This work deals with the development of a novel procedure to synthesize titania-modified nano structured carbon employing Ti-SBA-15 as hard template. The new mesoporous carbon displays high specific surface area of 1044 m2/g and large pore volume of 0.7 cm3/g. XRD pattern of Ti-CMK-3 indicates that the ordered structure of this material is similar to the CMK-3. XRD, XPS and UVeVis-DRS analysis indicated that Ti is highly dispersed as anatase phase in Ti-CMK-3. The synthesized Ti-CMK-3 exhibited significantly enhanced H2 storage properties (2.6 wt%, equivalent to 13 mmol/g) compared with CMK-3 without Ti (2.2 wt%, 11 mmol/g) at 77 K and 10 bar.
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    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 María
    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 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.
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    Bimetallic platinum/iridium modified mesoporous catalysts applied in the hydrogenation of HMF.
    (Universidad Tecnológica Nacional., 2021) Ledesma , Brenda Cecilia; Juárez , Juliana María; Mazario , Jaime; Domine, Marcelo; Beltramone , Andrea Raquel; Juárez , Juliana María
    Catalytic transformation of 5-hydroxymethylfurfural (HMF) to produce 2,5-dimethylfuran (2,5-DMF) was stu- died over bimetallic (PtIr) and monometallic (Pt) catalysts supported on CMK-3 and SBA-15 mesoporous ma- terials. The optimum temperature and hydrogen pressure for the maximum production of 2,5-DMF were 120 °C and 15 atm, respectively. Increases in temperature and pressure decreased the selectivity to 2,5-DMF. The cat- alysts were broadly characterized by different techniques, such as XRD, N2-isotherms, XPS, TPR, TEM and NH3- TPD. It was found that the metallic particles were well reduced and highly dispersed on the surface of supports having large surface area and narrow pore size distribution. The PtIr alloy species catalytic sites were very active and selective towards the formation of the desired 2,5-DMF. PtIr-CMK-3 catalyst showed an excellent activity, selectivity and stability to be applied in this process.
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    Vanadium and titanium oxide supported on mesoporous CMK-3 asnew catalysts for oxidative desulfurization.
    (Universidad Tecnológica Nacional., 2016) Rivoira , Lorena Paola; Juárez , Juliana María; Falcón , Horacio; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Juárez , Juliana María
    Vanadium 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 dibenzothiophene.