Desarrollo, Producción e Innovación en la Investigación científica
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Item Sílica Gel como fuente de silicio: Síntesis y caracterización de matrial mesoporoso.(Univesidsad Tecnológica Nacional., 2015) Ponte , María Virginia; Martínez , María Laura; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Martínez , María LauraEl material mesoporoso SBA-3 fue sintetizado mediante el método sol-gel, utilizando silicato de sodio como fuente de silicio y bromuro de hexadeciltrimetilamonio (CTAB) como agente director de estructura en condiciones acidas. El silicato sódico se generó in-situ por disolución de silica gel en NaOH. Se estudió el efecto de la variación de temperatura, la concentración de NaOH, y el tiempo de reacción. El mejor material mesoporoso con estructura SBA-3 fue obtenido con las siguientes condiciones de síntesis: temperatura: 25ºC; tiempo de reacción: 45min; concentración de NaOH: 0.8M.Item Eliminación de azufre mediante desulfuración oxidativa con Ti-SBA-16. Parte I. Síntesis y caracterización.(Univesidsad Tecnológica Nacional., 2015) Rivoira , Lorena Paola; Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Ponte , María Virginia; Martínez , María Laura; Beltramone , Andrea Raquel; Martínez , María Laura; Ponte , María Virginia; Ledesma , Brenda Cecilia; Ledesma , Lorena Paola; Vallés , Verónica AlejandraSe desarrollaron catalizadores tipo SBA-16 modificados con Ti como TiO2 y como heteroatomo y se probaron en la desulfuración oxidativa (ODS) del dibenzotiofeno predominante en el combustible líquido. Se utilizó TiO2 puro como referencia para comparar la actividad catalitica. Los catalizadores fueron caracterizados mediante análisis químico, XRD, EDX y TEM. El estado de coordinación tetraédrico del titanio (en la muestra de Ti-SBA-16) u octaédrico (en la muestra de TiO2/SBA-16) en la matriz de sílice se determinó por XPS, UV-vis DRS, FTIR, Raman y XANES. La actividad catalítica se muestra en la Parte 2 de este trabajo.Item Tetralin Hydrogenation over Ir-Pt/SBA-15. Optimization by experimental desing.(Univesidsad Tecnológica Nacional., 2015) Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Rivoira , Lorena Paola; Cussa , jorgelina; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Cussa , jorgelina; Rivoira , Lorena Paola; Ledesma , Brenda CeciliaBimetallic catalysts have received considerable attention for hydrotreating (HDT) because they show high activity. The features of the catalysts here studied are going to be correlated with their catalytic performance in the hydrogenation of tetralin at mild conditions. The final goal is to find the optimal proportion of each metal in order to be more active and the best reaction conditions (temperature and amount of catalyst). The statistical experiments design is the process of planning an experiment to obtain appropriate data that can be analyzed by statistical methods, to produce concrete and valid conclusions. One of the main advantages in the response curve is to visualize the response for all levels of the experimental factors Experiment design response surface methodology (RSM) is used in this work to model and to optimize the process. Platinum and Iridium nanoparticles were incorporated into SBA-15 support by the wet co impregnation method. Ir content was set as 1wt. % and Pt was varied from 0 to 1wt. %. The catalysts were characterized by XRD, BET, XPS, TEM, ICP and TPR. XRD profiles are characteristic of the two-dimensional p6mm hexagonal mesostructure with d100 spacing of 10.16 nm; where the d100 spacing upon Ir and Pt incorporation were quite similar to pristine SBA-15. The TEM images and XPS demonstrate that the metal particles were mainly present inside the porous and XPS and TPR corroborated the reduced state of the metals. The catalytic activity was measured in a 4563Parr reactor at 15 atm of hydrogen and 360 rpm. Feed consisted in 50 mL of tetralin in Dodecane, the amount of tetralin is set according to the ratio of catalyst mass/mass reagent corresponding to each reaction. The application of this methodology allows a better understanding of the influence of the different factors: content of metal on catalyst (A), relationship: mass of catalyst/reagent mass (B) and reaction temperature (C), on two responses: conversion at 3 h and at 5 h of reaction time. These factors were carefully selected taking account the influence of the parameters in the reaction. The design was analyzed by Statgraphics and Statistica Soft. We found that, the variable Catalyst has the best influence over the Conversion at the 95.0% confidence level, according to the Pareto.Item Hydrodenitrogenation of over Ir supporteD Ti-SBA-15 modified with F AND AI.(Univesidsad Tecnológica Nacional., 2015) Ledesma , Brenda Cecilia; Vallés , Verónica Alejandra; Rivoira , Lorena Paola; Balangero, Gerardo Simón; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Rivoira , Lorena Paola; Vallés , Verónica AlejandraThe hydrodenitrogenation of Indole has been studied over a series of Ti-modified SBA 15 supports and their respective Ir-catalysts. Ti-SBA-15 was synthesized using sol-gel method and Ti was added during the synthesis using TEOT as Ti source. Ti was incorporated into the framework replacing the Si atoms in the mesoporous structure. Ir/Ti-SBA-15 with and without F and/or Al were prepared to improve the catalytic activity. F and Al have been incorporated by wetness impregnation method. The effect of the incorporation of F and Al in the mesoporous structure was tested in the hydrodenitrogenation reaction of indole. The catalysts were extensively characterized by X-ray diffraction (XRD), N2 adsorption isotherms, TEM, FTIR and UV-vis-DRS and Raman spectroscopy. The low angle X-ray analysis showed for all the materials intensive reflection, characteristic of SBA-15 structure. The mesoporous structure was maintained after F and Al incorporation. The results showed that Ti incorporation reduces significantly the cluster size and improves considerably the Ir cluster dispersion. The catalytic activity of Ir/Ti-SBA-15 modified with F and Al, with higher acidity, avoided the irreversible adsorption of indole. The catalytic activity was studied in a 4563 Parr reactor, at 250°C, 15 atm of pressure of hydrogen and 360 rpm. The catalysts synthesized had good activity measured in hydrodenitrogenation of indole at mild conditions. The preliminary results show these materials as promising catalysts for HDN reactions.Item Uncertainty propagation of meteorological and emission data in modeling pollutant dispersion in the atmosphere(Ingenieria e Investigación, 2014) Diez, Sebastián César; Barra, E.; Crespo, S.; Britch, JavierLa variabilidad es la heterogeneidad real dentro de una población, que no puede ser reducida ni eliminada por más o mejores determinaciones. La incertidumbre representa la ignorancia acerca de un fenómeno pobremente caracterizado, pero que puede reducirse mediante la recopilación de más datos. El objetivo de este trabajo es estimar la concentración de PM10 provocada por las emisiones de una fuente puntual ubicada en Malagueño (Córdoba, Argentina), considerando la variabilidad y la incertidumbre de la meteorología y las emisiones. Para abordar este análisis fue desarrollado un método que utiliza los algoritmos del modelo Industrial Source Complex de la USEPA junto a la metodología Monte Carlo. Con cien mil iteraciones se obtuvo la distribución de concentraciones, encontrándose que la incertidumbre en la dirección del viento es la de mayor incidencia sobre las estimaciones.Item Particulate matter concentrations originating from industrial and urban sources: validation of atmospheric dispersion modeling results(Elsevier B.V., 2015) Abril, Gabriela A.; Pignata, María Luisa; Diez, Sebastián César; Britch, JavierThis study presents the analysis of the emission, transport, dispersion, and concentration of particulate matter emitted from a large industrial complex dedicated to the manufacture of cement in the town of Malaguen~o, province of Co´rdoba (Argentina), using the USEPA's (Environmental Protection Agency) AERMOD model. The model was applied for 224 industrial and background emission sources (8 stacks, 3 limestone quarries, 13 material storage piles, 18 agricultural fields and 182 paved and unpaved segment roads). The application of the model was validated with Total Suspended Particulate matter (TSP) measured at two monitoring sites, where samples were collected for 62 consecutive days in winter. The maximum TSP values obtained at both monitoring sites (748 and 1100 mg m—3) were well above the suggested WHO guidelines. The results obtained showed the impact of this industrial activity on local particulate matter concentrations, from which unpaved industrial roads and stockpiles were the most influential emission sources, directly affecting two of the closest neighborhoods in the area. Future studies will include the accumulation of heavy metals and Polycyclic Aromatic Hydrocarbons in TSP samples, the environmental risk assessment for exposure of the Malaguen~o population and the source apportionment of these pollutantsItem Inhibition by nitrogen compounds in the simultaneous hydrogenation of polyaromatic compounds over Pt-Pd-F/AI203 catalyst.(Univesidsad Tecnológica Nacional., 2015) Balangero , Gerardo Simón; Falcón, Horacio; Beltramone, Andrea RaquelThe inhibiting effect of basic and non-basic nitrogen compounds on the hydrogenation of polyaromatic compounds and on the hydrodesulphurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6DMDBT), has been investigated on Pt-Pd-F/Al2O3 and compared with a commercial NiMo hydrotreating catalyst. Langmuir-Hinshelwood type rate equations were used to describe the reaction kinetics accurately with physically meaningful and well identified parameter values. Model parameters were tuned by fitting experimental data obtained in a continuous flow reactor at 345°C, 1000 psi pressure and different contact times. Pt-Pd-F/Al2O3 was more active than NiMo catalyst and conversion remained constant during 24 h of TOS. The model was able to correctly interpret all the experimental data. Parameter estimation results showed that phenanthrene and naphthalene inhibited the tetralin hydrogenation rate, whereas naphthalene and tetralin had no appreciable effect on the rate of phenanthrene conversion. This inhibition could be explained by the competitive adsorption and was described in the kinetic model by adsorption terms obtained from the multicomponent experiments. The inhibiting effect of different nitrogen compounds on the polyaromatic hydrogenation was determined. The following nitrogen compounds were investigated in this study: quinoline, 1,2,3,4-tetrahydroquinoline, indole, and indoline. The degree of inhibition was expressed in terms of an apparent adsorption constant derived from the kinetics.The inhibiting effect on the HDS of DBT and 4,6 DBT followed the same trend.Item ODS of dibenzothiopene with 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 Raquel; Anunziata , Oscar Alfredo; Martínez , María LauraOver 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 attrac tive properties, including lower temperature and pressure conditions and lower operating cost [1-3] than conventional hydrodesulfurization (HDS) process. Oxidation of organosulfur com pounds 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, diben zothiophene 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 [4-6]. We recently reported a good performance of this sup port in hydrotreating processes [7]. In this work, we describe the preparation and characteriza tion 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 tempe rature, nature of the substrate and reuse of catalysts)Item Experimental Desing Optimization of the tetralin Hydrogenation over Pt-Ir/SBA-15.(Univesidsad Tecnológica Nacional., 2015) Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Rivoira , Lorena Paola; Cussa , jorgelina; Anunziata , Oscar Alfredo; Beltramone, Andrea Raquel; Anunziata , Oscar Alfredo; Cussa , jorgelina; Rivoira , Lorena Paola; Ledesma , Brenda Ceciliahe oil refining industry has a difficult challenge to meet the increasingly stringent regula tions on environmental issues. Contaminants such as sulfur, nitrogen, fused ring aromatic compounds or metals are the principal to remove to achieve "green" fuels. The hydrotreating (HDT) is one of the processes most used in the refinery to remove these contaminants. To optimize the gas oil hydrotreater, it is crucial to understand the aromatic hydrogenation reac tion chemistry occurring in the gas oil hydrotreater. To find alternative processes, it is neces sary to develop new and more active catalysts to replace the current ones. Bimetallic Pt–Pd catalysts have received considerable attention, because they show high actvity in a variety of catalytic applications [1,2]. From a fundamental point of view, exploring bimetallic catalysts also allows better understanding of mechanisms and variables involved in the catalytic reac tions. The features of the catalysts here studied are going to be correlated with their catalytic performance in the hydrogenation of tetralin. The final goal is to find the optimal proportion of each metal in order to be more active and the best reaction conditions. The statistical expe riments design is the process of planning an experiment to obtain appropriate data that can be analyzed by statistical methods, to produce concrete and valid conclusions [3]. One of the main advantages in the response curve is to visualize the response for all levels of the experi mental factors Experiment design response surface methodology (RSM) is used in this work to model and to optimize the process.Item Sulfur elimination by oxidative desulfurization with titanium-modified SBA-16L.(Univesidsad Tecnológica Nacional., 2016) Rivoira , Lorena Paola; Vallés , Verónica Alejandra; Ledesma , Brenda Cecilia; Martínez , María Laura; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Martínez , María Laura; Ledesma , Brenda Cecilia; Vallés , Verónica AlejandraOver 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 attrac tive properties, including lower temperature and pressure conditions and lower operating cost [1-3] than conventional hydrodesulfurization (HDS) process. Oxidation of organosulfur com pounds 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, diben zothiophene 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 [4-6]. We recently reported a good performance of this sup port in hydrotreating processes [7]. In this work, we describe the preparation and characteriza tion 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 tempe rature, nature of the substrate and reuse of catalysts).