1,721,026 research outputs found
Production, use, and upgrading of natural gas in Argentina
Get PDFThis work briefly reviews the economic, energetic, industrial, and environmental roles that natural gas plays nowadays in Argentina. The evolution of natural gas production and consumption in Argentina over the last decades is analyzed and compared with other Latinamerican countries. The use of natural gas as ground transportation fuel is presented, taken into account that about 7% of the Argentine vehicle fleet are composed of natural gas fueled vehicles. The role of catalytic technologies for transforming natural gas into cleaner fuels and valuable chemicals is also discuss.Fil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin
Workshop on catalytic technologies for environmentally benign processes
Get PDFFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Resasco, Daniel E.. Oklahoma State University; Estados Unido
Gas-phase synthesis of hydroxyacetophenones by acylation of phenol with acetic acid
No full textThe gas-phase synthesis of aromatic ketones via acylation of phenol with acetic acid was studied on SiO2–Al2O3, Al-MCM-41, zeolites HY and ZSM5, and tungstophosphoric acid (HPA) supported on MCM-41 and carbon. At contact times of 146 g h/mol, the initial conversion of phenol varied between 12.5% (HY) and 19.1% (HPA/MCM-41), and the initial selectivity to ortho-hydroxyacetophenone (o-HAP) between 37.1% (HPA/C) and 69.1% (HY). In all the cases, the formation of o-HAP was clearly favored in comparison to that of para-isomer. Zeolites HY and ZSM5, which contained strong Brønsted and Lewis acid sites, produced efficiently o-HAP via both the direct C-acylation of phenol and the acylation of phenyl acetate intermediate formed from O-acylation of phenol. HPA-based catalysts contained only Brønsted acid sites and formed o-HAP exclusively as a secondary product from phenyl acetate. The o-HAP yield remained constant with time on stream on ZSM5 but drastically decreased on the other samples because of coke formation. The superior stability of zeolite ZSM5 was interpreted by considering that coke precursor formation is avoided into the microporous structure of this zeolite.Fil: Padro, Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin
Self-metathesis of methyl oleate on silica-supported Hoveyda-Grubbs catalysts
Get PDFThe self-metathesis of methyl oleate (MO) to yield 9-octadecene and 9-octadecene-1,18-dioate (9-OD) was studied in liquid-phase on silica-supported Hoveyda–Grubbs complex catalysts (HG/SiO2) containing 0.43–6.0 wt.% HG. The reaction was carried out in a batch reactor at 303–343 K and 101.3 kPa, using cyclohexane as solvent.
HG/SiO2 catalysts were active and highly selective for the MO metathesis reaction; equilibrium values of MO conversion and 9-OD yield were reached in 80 min. No catalyst leaching took place in cyclohexane. Catalysts containing HG N0.87 wt.% showed no significant deactivation after two consecutive catalytic tests.Fil: Zelin, Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Trasarti, Andres Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin
Nuevos procesos catalíticos ecocompatibles en química fina: Síntesis de iononas
Get PDFSe estudio la ciclizacion en fase liquida de pseudoionona a iononas Cisomeros ALFA, BETA Y GAMA) sobre zeolita HBEA, resina Amberlyst 35W, Si02-Al20g, HPA/Si02 y Cs-HPA. La resina Amberlyst 35W y HPA/Si02fueron los catalizadores mas activos mostrando que la formacion de iononas es promovida preferentemente por sitios acidos fuertes de Br¢nsted. En particular, el catalizador 58.5% HPA/Si02 produjo un rendimiento a iononas del 79% despues de 1.5 h de reaccion a 383 K y 250 kPa. Este rendimiento es similar a los mejores valores informados en la literatura cuando la reaccion se lleva a cabo en fase homogenea usando acido sulfurico.Fil: Diez, Veronica Karina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Di Cosimo, Juana Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; ArgentinaFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentin
Acid-base properties and active site requirements for elimination reactions on alkali-promoted MgO catalysts
Get PDFBase-catalyzed elimination reactions were studied on MgO and alkali-modified MgO catalysts using 2-propanol as a probe reactant. The effect of the acid–base properties on the catalyst activity and selectivity was investigated by modifying the surface properties of MgO with 1 mol% of alkaline metals. Group IA metals promote the formation of medium- and high-strength basic sites, thereby increasing the basic site density and strength. The addition of alkaline promoters improves the MgO activity for 2-propanol conversion reactions. The selectivity toward dehydration or dehydrogenation products depends on the base site nature, so that intermediate-strength base sites promote acetone formation, whereas high-strength base sites selectively yield propylene. 2-Ppropanol decomposition to acetone and propylene is proposed to take place via an E1cB mechanism in two parallel pathways sharing a common 2-propoxy intermediate.Fil: Diez, Veronica Karina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Di Cosimo, Juana Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin
Chemoselective hydrogenation of unsaturated nitriles to unsaturated primary amines: Conversion of cinnamonitrile on metal-supported catalysts
No full textThe liquid-phase hydrogenation of cinnamonitrile (CN) to selectively obtain the unsaturated primary amine (cinnamylamine) was studied at 383 K and 13 bar on Ni, Co, Ru and Cu metals supported on a commercial silica. Ni/SiO2 and Co/SiO2 were the most active catalysts for cinnamonitrile conversion but formed only small amounts of cinnamylamine. In contrast, Cu/SiO2 and Ru/SiO2 presented low activity for cinnamonitrile hydrogenation but formed selectively cinnamylamine in the liquid phase; nevertheless, on both samples the carbon balance was only about 40%. In an attempt of promoting the rate and yield to cinnamylamine, additional catalytic runs were carried out at higher temperatures and H2 pressures on a highly dispersed Cu(11%)/SiO2 catalyst prepared by the chemisorption-hydrolysis method. Results showed that when cinnamonitrile hydrogenation was performed at 403 K and 40 bar on Cu(11%)/SiO2, the yield to cinnamylamine was 74% giving as by-product only the unsaturated secondary amine (dicinnamylamine).Fil: Segobia, Dario Jobino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Trasarti, Andres Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin
Synthesis of menthols from citral on Ni/SiO2-Al2O3 catalysts
Get PDFThe one-pot synthesis of menthols from citral was studied on Ni/SiO2-Al2O3 catalysts containing 3.6%, 8.8% and 11.4% Ni. The yield of menthols increased with the amount of Ni up to 94% on Ni(11.4%)/SiO2-Al2O3, reflecting the diminution of byproducts formation via acid-catalyzed reactions. The sample deactivation was studied by performing two consecutive catalytic tests. Results showed that Ni(11.4%)/SiO2-Al2O3 was a stable, active, and highly selective catalyst because it contained the appropriate density and strength of bifunctional acid/Ni(0) active sites to efficiently promote the hydrogenation/isomerization pathway involved in the reaction network while avoiding coke formation.Fil: Trasarti, Andres Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera"; ArgentinaFil: Marchi, Alberto Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera"; ArgentinaFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones En Catalisis y Petroquímica "ing. Jose Miguel Parera"; Argentin
Impact of solvent on Co/SiO2 activity and selectivity for the synthesis of n-butylamine from butyronitrile hydrogenation
Get PDFThe impact of solvent on Co(9.8%)/SiO2 activity and selectivity for the synthesis of n-butylamine from the liquid-phase butyronitrile hydrogenation was investigated at 373 K and 13 bar using methanol, benzene, toluene and cyclohexane as solvents. In non-polar solvents, the yield of nbutylamine increased from 60% to 79% following the order cyclohexane < toluene < benzene. Nevertheless, the highest n-butylamine yield (91%) was obtained in methanol, a protic solvent. The solvent effect on the catalyst performance was interpreted by considering: i) the solvent-catalyst interaction strength that was investigated by temperature-programmed desorption of solvents characterized by mass spectrometry; ii) the solvent polarity and its ability for H-bond formation with n-butylamineFil: Segobia, Dario Jobino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Trasarti, Andres Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin
Production of bio-hydrogen by liquid processing of xylitol on Pt/Al2O3 catalysts: Effect of the metal loading
Get PDFThe aqueous-phase reforming of xylitol to produce bio-hydrogen was studied on Pt/Al2O3 catalysts containing 0.30, 0.57, 1.50 and 2.77%wt Pt by varying the weight hourly space velocity (WHSV) between 0.6 and 2.4 h−1. At a constant WHSV value, the gaseous/liquid products ratio depended on the amount of surface Pt concentration on the sample (Pts). The xylitol conversion to gaseous products increased with Pts while xylitol conversion to liquid products did not change significantly. At a constant xylitol conversion, the H2 selectivity increased with Pts. The H2 yield increased continuously with both contact time and Pts. The H2 productivity (Pr, mmol H2/h gcat) increased with both WHSV and Pts; indeed, the maximum Pr value obtained when using 1% xylitol in the feed (28 mmol H2/gcat h) was obtained on Pt(2.77)/Al2O3 catalysts at WHSV = 2.4 h−1. The effect of the xylitol concentration on H2 productivity was also investigated. At a constant space velocity, the H2 selectivity and productivity decreased with increasing xylitol concentration in the feed.Fil: Duarte, Hernán Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Sad, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; ArgentinaFil: Apesteguia, Carlos Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentin
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