Facultad Regional Córdoba
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Item Vanadium and titanium oxide supported on mesoporous CMK-3 as new catalysts for oxidative desulfurization.(Univesidsad Tecnológica Nacional., 2016) Rivoira , Lorena Paola; Juárez , Juliana María; Falcón , Horacio; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaVanadium 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 dibenzothiopheneItem Sulfur elimination by ODSwith titanium-modified SBA-16.(Univesidsad Tecnológica Nacional., 2015) Rivoira , Lorena Paola; Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Martínez , María Laura; Anunziata , Oscar Alfredo; Beltramone, Andrea RaquelOver the past, oxidative desulfurization (ODS) has drawn considerable interest as a new alter-native method for deep sulfur elimination from light oils. This can be attributed to its attractive properties, including lower temperature and pressure conditions and lower operating cost than conventional hydrodesulfurization (HDS) process. Oxidation of organosulfur compounds results in the formation of sulfoxides/sulfones, highly polar and hence easily removed by both extraction into polar solvents or by adsorption. Due to their low reactivity, dibenzothiophene derivatives (DBTs) are the most refractory species to be eliminated from oils. Hence, the ODS process through which DBTs are converted to their corresponding sulfones involves great interest at present. In this work, we describe the preparation and characterization of new mesoporous catalytic materials based on Ti-containing SBA-16. We study here, the effect of the preparation method of titania-modified SBA-16 (characteristics of the active Ti and/or TiO2 species) and the effect of the different operation conditions in ODS of DBT under mild conditions in order to find the best performance. TiO2-modified mesoporous SBA-16 and titanium-substituted mesoporous SBA-16 were developed and tested in the oxidative desulfurization (ODS) of dibenzothiophene prevailing in liquid fuel. We assessed the impact exerted on performance of different reaction variables, including (nature and amount of the active catalytic species, phase system, molar ratio of oxidant H2O2 and DBT, reaction temperature, nature of the substrate and reuse of catalysts). We achieved 90% of S removal from a 0.2 wt.% dibenzothiophene solution at 60°C in less than 1 h of reaction. The best catalytic results are obtained with high exposed surface of nanometric TiO2 species of TiO2/SBA-16 sample. The activated catalyst is very active in ODS reaction and can be reused four times with no loss in activityItem Nanostructured SBA-15 host: synthesis, characterization and application in ketorolac-tromethamine release system.(Univesidsad Tecnológica Nacional, 2016) Cussa , jorgelina; Juárez , Juliana María; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Juárez , Juliana MaríaThe ordered mesoporous silica SBA-15 has been applied in studies of ketorolac tromethamine adsorption and release. The SBA-15 materials with hexagonal and regular structure were obtained using a triblock copolymer Pluronic P123 as template and TEOS as a silica source[1]. Drug delivery is an emerging field mainly focused on aiming drugs. The goal of this targeted delivery is to transport an amount of drugs to desirable sites (such as tumors and diseased tissues) while minimizing unwanted side effects of the drugs on other tissues [2]. Controlled drug delivery systems can achieve precise spatial and temporal delivery of therapeutic agents to the target site. Ketorolac tromethamine was adsorbed into SBA-15 silica nanochannels using ethanol as solvent. The physicochemical and textural properties of SBA-15 and ketorolac tromethamine/SBA-15 were characterized by X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, Fourier transform infrared spectroscopy and BET surface studies. Drug release was evaluated by soaking the loaded silica mesoporous material into a solution of HCl (0.1N) at 37 ºC under continuous stirring. Release studies were performed in order to evaluate the required therapeutic efficacy. SBA-15 provides significant improvement in the controlled release of ketorolac tromethamine [3]. In this work, we have shown a promising drug storage material for the effective encapsulation and controlled release of KETO, achieving the required therapeutic efficacy. SBA-15/KETO shows characteristic bands of both, drug materials and the inorganic framework. This indicates that KETO was adsorbed into SBA-15 channel surface without affecting the chemical structure or composition of KETO. The study also demonstrates the storage capacity and release properties of SBA-15 containing KETO. The release of KETO contained in SBA-15 can offer significant improve in controlled drug release and enhance a good analgesia effect.Item LP-SBA-15-TBA-CP: Tert-Butylamine and Cyclophosphamide detailed study by FTIR and 3D structure.(Univesidsad Tecnológica Nacional, 2023) Anunziata , Oscar Alfredo; Cussa, JorgelinaA careful study of the vibrational spectra of the host (LP-SBA-15), functionalizing agent, tert-Butylamine (TBA), and N, N-bis(2-chloroethyl)tetrahydro-2H-1,3,2- oxazaphosphorin-2-amine 2-oxide, cyclophosphamide (CP) was performed, as there is a diversity of assignments published by different authors [1-5]. Our preliminary OM studies (AM1, PM3, Density Functional Theory, application of the Fukui function), and extensive FTIR studies, we estimated the binding energies, bond lengths and bond angles of CP as well as for TBA-CP, leading us to suggest that CP is embedded in an ellipsoid.