Desarrollo, Producción e Innovación en la Investigación científica
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Item Óxidos de vanadio y titanio soportados sobre CMK-3 como un nuevo catalizador para la desulfuración oxidativa de DBT.(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 MaríaEn el presente trabajo se estudiaron catalizadores de vanadio soportados sobre el carbón mesoporosos CMK 3 con diferentes contenidos de Vanadio (1-7 % p/p) en la desulfurización oxidativa de dibenzotiofeno (DBT) como modelo de compuestos sulfurados. La actividad catalítica se comparó con catalizadores de Titanio soportados en CMK-3. Las propiedades estructurales y texturales de los catalizadores se analizaron mediante estudios de adsorción de N2, XRD, UV-Vis-DRS y TEM. Tanto la dispersión como la actividad catalítica dependen fuertemente del contenido de vanadio. La muestra que contiene el 7% p/p de Vanadio es el catalizador con mejor actividad catalítica para la reacción de ODS de DBT utilizando peróxido de hidrógeno ((H2O2) como oxidante y acetonitrilo como solvente. El 100% de la eliminación de DBT se alcanzó a corto plazo en condiciones suaves. El carbon mesoporoso CMK-3 con una alta área superficial y gran volumen de poros promueve el anclaje del metal en la red de carbono, lo que permite alcanzar una alta distribución de sitios activos y nanoclusters más estables. La reutilización del catalizador indica que V-CMK-3 es un catalizador potencial para los ODS de dibenzotiofeno.Item Synthesis and characterization of a nanoporous carbon CMK-3 modified with iron for the ODS of DBT.(Univesidsad Tecnológica Nacional., 2017) Juárez , Juliana María; Rivoira , Lorena Paola; Gómez Costa, Marcos Bruno; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Rivoira , Lorena PaolaA nanostructured Carbon CMK-3 modified with Fe by using different sources of Fe, were used in the oxidative desulfurization (ODS) of dibenzothiophene as a model sulfur compound. Ordered mesoporous carbon CMK-3 was synthesized via a two-step impregnation of the SBA-15 silica mesonanopores with a solution of sucrose using an incipient wetness method. The sucrose–silica composite was heated at 1173 K for 4 h under nitrogen flow. The silica template was dissolved in 5 wt.% hydrofluoric acid in order to remove the silica. The template-free carbon product thus obtained was filtered, washed with deionized water and ethanol and dried. Fe-CMK-3 was prepared by wetness impregnation using FeCl3.6H2O and FeNO3.9H2O as different sources of Fe. A solution of FeCl3.6H2O/ FeNO3.9H2O in ethanol was mixed with the carbon solution at room temperature. The solution was placed in a rotary evaporator to remove excess of ethanol at about 333 K and 60 rpm. Afterwards, the sample was dried at 373 K for 18 h and was thermally treated in a dynamic inert (N2) atmosphere. The percentage of Fe has been 2 wt.% with respect to carbon in the final FeCl3-CMK-3 and FeNO3-CMK 3 material. Porous carbon CMK-3 and the samples modified with Fe were characterized by XRD, FTIR, XPS, BET, TEM and SEM. These studies indicated that it was possible to obtain a CMK-3 replica successfully from SBA-15, using sucrose as a carbon precursor. Wide angle XRD pattern of the sample modified with FeCl3.6H2O implies the formation of the magnetite phase in the silica channels. The surface areas were 1320 m2/g for the CMK-3 and 1240 m2/g and 609 m2/g for FeCl3- CMK-3 and FeNO3-CMK-3, respectively. While the nanomaterial area is significantly smaller with the incorporation of the metal, CMK-3`s characteristic structure is maintained after the metal is within the host, in agreement with the XRD studies. The catalytic activity was improved when the nanoporous carbon was modified with Fe. The sample modified with FeCl3.6H2O 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 a short time in mild conditions.Item Novel preparation of titania-modified CMK-3 nanostructured material as support for Ir catalyst applied in hydrodenitrogenation of indole.(Univesidsad Tecnológica Nacional., 2018) Ledesma , Brenda Cecilia; Juárez , Juliana María; Vallés , Verónica Alejandra; Anunziata , Oscar Alfredo; Beltramone , Andrea Raquel; Anunziata , Oscar Alfredo; Vallés , Verónica Alejandra; Juárez , Juliana MaríaIridium catalyst was prepared using a novel titanium oxide-CMK-3 support synthesized as a replica of Ti-SBA-15. The catalyst was applied in the hydrodenitrogenation of indole. The activity was compared with an iridium catalyst supported over a grafted titanium 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 H2 Chemisorption. Ir-Ti-CMK-3 was the most active catalyst for the hydrodenitrogenation reaction at mild conditions. Titanium oxide contained in carbon ordered mesoporous CMK-3 promotes a very good anchorage of iridium metallic clusters in the carbon framework reaching high active site distribution and more stable nanoclustersItem Novel and simple one-pot method for the synthesis of titanium modified-CMK-3 applied in desulfurization of refractory oeganosulfur compounds.(Univesidsad Tecnológica Nacional., 2018) Rivoira , Lorena Paola; Ledesma , Brenda Cecilia; Juárez , Juliana María; Beltramone, Andrea Rauqel; Juárez , Juliana María; Ledesma , Brenda CeciliaTi-CMK-3 carbon mesoporous was prepared using a novel synthesis method. This new method avoids the hard template synthesis used commonly. The method developed here, allows reducing time, energy consumption and cost. Our primary aim in this work is to evaluate the ODS activity of the Ti-modified mesoporous carbon CMK-3, synthesized by the short time method, in order to achieve total removal of sulfur compounds from diesel fuel. The catalytic oxidation of the sulfur compound with hydrogen peroxide was carried out in a glass batch reactor, equipped with a magnetic stirrer, a thermometer and a condenser. In a typical run, the solid catalyst (60 mg) was suspended under stirring (750 rpm) in 20 mL of a solution of 500 ppm of S as DBT (or other) in acetonitrile. Then, appropriate amount of 30% aqueous H2O2 was added at constant temperature. The experiments were performed in a three-phase liquid-liquid-solid (L (oil) –L (solvent) –S (catalyst)) system, acetonitrile was used as solvent and dodecane as oil phase. Solution samples were recovered at various times. The products were analyzed by GC HP 5890 Series II with a HP-5 column and connected to FID and PFPD detectors, after filtration and eventually decantation step. The products were confirmed using a Shimadzu GCMS. Structural and textural characterization of the titanium modified-mesoporous carbon was performed by N2 adsorption, XRD, UV-Vis-DRS, XPS, Raman spectroscopy and TEM. The characterization results indicated that the textural and structural properties of the material synthesized by the short time method are comparable with the properties of the material prepared by the hard template method. Ti modified-mesoporous carbon was synthesized by different methods in order to prepare catalysts to be tested in the oxidative desulfurization (ODS) of sulfur compounds. The good performance and stability of the catalyst prepared using a novel synthesis method was attributed to well dispersed anatase nanospecies over the high area mesoporous carbon. Main advantage of the present study is the reduction of time and cost in the synthesis of the new material and the applicability for ODS reactions.Item Iron modified mesoporous materials as catalysts for ODS of sulfur compounds.(Univesidsad Tecnológica Nacional., 2018) Rivoira , Lorena Paola; Juárez , Juliana María; Martínez , María Laura; Beltramone, Andrea Raquel; Martínez , María; Juárez , Juliana MaríaSe aplicaron catalizadores mesoporosos modificados con Fe en la reacción de ODS de DBTs, utilizando H2O2 como oxidante y acetonitrilo como solvente. Los soportes utilizados fueron SBA-15, MCM-48, CMK-3 y CMK-1.El hierro se incorporó mediante impregnación húmeda utilizando nitrato de hierro. Los catalizadores se caracterizaron por XRD, isotermas de N2, TEM, XPS e ICP. Hemos desarrollado catalizadores con gran área específica y volumen de poro, distribución estrecha del tamaño de mesoporos y especies de hierro altamente dispersas. Se probaron los catalizadores en desulfuración oxidativa de diferentes compuestos de azufre tales como benzotiofeno (BT), dibenzotiofeno (DBT) y 4,6-dimetil dibenzotiofeno 4,6-DMDBT). El catalizador preparado con CMK-3 como soporte fue el más activo para la reacción de ODS. La buena actividad se relacionó con la elevada dispersión de óxidos de hierro, principalmente en la fase magnetita. En la oxidación de DBT y utilizando Fe-CMK-3 se estudiaron la temperatura, peróxido de hidrogeno y concentración inicial de azufre. Se determinaron las condiciones óptimas de operación. Fe-CMK-3 es un catalizador activo y estable para ser aplicado en el proceso industrial de ODS. Palabras clave: SBA-15, MCM-48, CMK-3, CMK-1, Fe.Item CMK-3 modificada con titanio obtenida mediante un novedoso y rápido método de síntesis aplicada en la desulfuración oxidativa de compuestos organosulfurados.(Univesidsad Tecnológica Nacional., 2018) Rivoira , Lorena Paola; Ledesma, Brenda Cecilia; Juárez , Juliana María; Beltramone , Andrea Raquel; Juárez , Juliana María; Ledesma, BrendaEl nanomoldelado de materiales ha sido el único método para crear materiales mesoporosos de carbono, utilizando plantillas inorgánicas (Ezzeddine et al., 2016). Involucra una última etapa donde se elimina el agente plantilla, lo cual lo hace complicado, largo y de elevado costo. Recientemente Ledesma et al. (2017) demostraron la posibilidad de un método de síntesis más corto para obtener CMK-3 modificada con Ti incorporando las especies de Ti directamente en la estructura del carbón mesoporoso utilizando Ti-SBA-15 como agente plantilla. En la reacción de ODS ocurre la oxidación de aquellos compuestos de S más refractarios en la HDS, utilizando de un agente oxidante en presencia de un catalizador (Subhan et al., 2012). Es necesario agregar un solvente polar al sistema, capaz de extraer las moléculas de S desde la fase diesel para que pueda estar en contacto con el agente oxidante (H2O2, polar) y el catalizador. En el presente trabajo se evalúa la actividad en la ODS de carbón mesoporoso CMK-3 modificado con Ti, sintetizado mediante un novedoso método más corto.Item Preparation and characterization of activated CMK-3 modified with vanadium applied in hydrogen storage.(Univesidsad Tecnológica Nacional, 2024) Juárez , Juliana María; Gómez Costa, Marcos Bruno; Cussa , jorgelina; Anunziata , Oscar Alfredo; Anunziata , Oscar Alfredo; Cussa , jorgelinaThe aim of this work is to synthesize a nanostructured Carbon CMK-3 modified with V in order to increase its capacity in hydrogen storage. The approach that we have followed includes synthesis of nanostructures with the experimental study of its adsorption capacity and storage properties. Ordered nanoporous carbon CMK-3 was synthesized via a two-step impregnation of the SBA-15 mesopores with a solution of sucrose using an incipient wetness method. The sucrose–silica composite was heated at 1173 K for 4 h under nitrogen flow. The silica template was dissolved with 5 wt% hydrofluoric acid in order to remove the silica. The template-free carbon product thus obtained was filtered, washed with deionized water and ethanol, and dried. [1] V-CMK-3 was prepared by wetness impregnation using VCl3 as source of Vanadium in order to increase the amount of hydrogen adsorbed. The sample of V-CMK-3 was treated under H2 flow two times at 1173 K. Porous carbon CMK-3 and the sample modified with V were characterized by XRD, FTIR, XPS, BET, TEM and SEM. These studies indicate that it was possible to obtain a CMK-3 replica successfully from SBA-15, using sucrose as a carbon precursor. [2] The surface areas are 1320 m2/g and 1050 m2/g for CMK-3 and V-CMK-3, respectively. While the nanomaterial area is significantly smaller with the incorporation of the metal, CMK-3`s characteristic structure is maintained after the metal is within the host, in agreement with the XRD studies. Measurements of hydrogen adsorption at cryogenic temperatures and low pressures were performed. The nanoparticles of V incorporated onto the nanostructured carbon CMK-3 showed higher hydrogen uptake at low and high pressures than CMK-3. (3.4 wt% and 2.2 wt% respectively of H2 sorption at 10 bar and 77 K).Item H2 storage using Zr-CMK-3 developed by a new synthesis method.(Univesidsad Tecnológica Nacional, 2021) Juárez , Juliana María; Venosta , Lisandro; Anunziata, Oscar Alfredo; Gómez Costa , Marcos Bruno; Anunziata, Oscar AlfredoOne of the biggest problems in using hydrogen as an alternative fuel is that its storage must be safe and portable. This work addresses a new direct synthesis technique used to obtain a novel mesoporous carbon (CMK-3) modified with zirconium oxide. This novel material shows promise for hydrogen adsorption and storage application for energy harvesting. Zirconium oxide (Zr-CMK-3) material is achieved through successful synthesis and characterized by XRD, SEM,Raman, BET, UV-Vis-DRS, XPS and TEM analyses. Zr-CMK-3 signifi- cantly improved H2 storage performance (reaching at 77 K and 10 bar 4.6 wt%) comparedto the pristine CMK-3. The novel material is favorable for H2 uptake by using weak bonding (physisorption). A hydrogen uptake mechanistic approach is proposed and the role of the Zr+4 cation in hydrogen adsorption is discussed.Item Synthesis and characteristics of CMK-3 modified with magnetite nanoparticles for application in hydrogen storage.(Univesidsad Tecnológica Nacional, 2020) Venosta, Lisandro; Juárez , Juliana María; Anunziata , Oscar Alfredo; Bercoff, Paula; Gómez Costa , Marcos Bruno; Anunziata , Oscar Alfredo; Juárez , Juliana María: In this work, we report the synthesis and characterization of iron oxide nanoparticles supported in nanostructured carbon (CMK-3). This material is promising in the application of hydrogen adsorption for energy storage. The material with iron oxide nano particles (Fe-CMK-3) was successfully synthesized and characterized by X-ray diffraction, textural properties analysis, transmission and scanning electron microsco py, X-ray photoelectron spectroscopy, and magnetiza tion 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 storage capacity of hydrogen (4.45 wt% at 77 K and 10 bar) compared with the CMK-3 framework alone (2.20 wt% at 77 K and 10 bar). The synthesized material is promising for hy drogen adsorption by weak bond forces (physisorption). A hydrogen adsorption mechanism was proposed in which the nanoparticles of magnetite have an important role.Item H2 storage using Zr-CMK-3 developed by a new synthesis method(2021) Juárez, Juliana María; Venosta, Lisandro F.; Anunziata, Oscar Alfredo; Gómez Costa, Marcos BrunoOne of the biggest problems in using hydrogen as an alternative fuel is that its storage must be safe and portable. This work addresses a new direct synthesis technique used to obtain a novel mesoporous carbon (CMK-3) modified with zirconium oxide. This novel material shows promise for hydrogen adsorption and storage application for energy harvesting. Zirconium oxide (Zr-CMK-3) material is achieved through successful synthesis and characterized by XRD, SEM, Raman, BET, UV-Vis-DRS, XPS and TEM analyses. Zr-CMK-3 signifi- cantly improved H2 storage performance (reaching at 77 K and 10 bar 4.6 wt%) compared to the pristine CMK-3. The novel material is favorable for H2 uptake by using weak bonding (physisorption). A hydrogen uptake mechanistic approach is proposed and the role of the Zr+4 cation in hydrogen adsorption is discussed.