Results 261 to 270 of about 76,034 (306)

New perspectives on basic zeolites as catalysts and catalyst supports

Journal of Catalysis, 2003
AbstractFor Abstract see ChemInform Abstract in Full Text.
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Methanolysis of triacylglycerols by organic basic catalysts

European Journal of Lipid Science and Technology, 2007
AbstractMethanolysis of rapeseed and soybean oil was studied using organic basic catalysts at boiling with reflux. The molar ratio methanol/free fatty acids (FFA) amounted to approx 2.8 : 1. The catalyst (guanidine carbonate) is used at concentrations between 0.5 and 1.3 wt‐% with respect to the oil.
Siegfried Peter, Eckhard Weidner
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Glucose–fructose isomerisation promoted by basic hybrid catalysts

Catalysis Today, 2012
As-synthesised mesoporous ordered molecular sieves of the M41S family, containing their organic template and used without any pretreatment, were shown to be efficient weak basic catalysts in glucose-fructose isomerisation in water at 100 degrees C. Selectivities higher than 80% were obtained for glucose conversion higher than 20%.
Souza, R. O. L., Fabiano, D. P., Feche, C., Rataboul, F., Cardoso, D., Essayem, N.   +5 more
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CsF supported by α-alumina: an efficient basic catalyst

Applied Catalysis B: Environmental, 2004
Abstract CsF supported by α- and γ-alumina was characterized by DTG-DTA coupled with mass spectral analysis of the gases evolved by the solid, XRD, 19 F NMR spectroscopy, and tested in the Michael addition of cyclohexene-2-one with nitroalkanes and in the synthesis of alkyl carbonates.
Clacens, J.-M., Genuit, D., Veldurthy, B., Bergerest, G., Delmotte, L., Garcia-Ruiz, A., Figueras, F.   +6 more
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Studies on solid catalysts with a basic character III. Nature of acidic and basic centers on the surface of sodium-silica catalysts

Journal of Catalysis, 1969
CO2 adsorption has been measured on seven silica catalysts containing different amounts of sodium. The results are compared with those of a previous study of ammonia adsorption. As with NH3, the adsorption of CO2 increases with sodium content, but evidence is presented to show that the centers for adsorption of CO2 and NH3 are different. The adsorption
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Sodium titanate as basic catalyst in transesterification reactions

Fuel, 2014
Abstract Sodium titanate was synthesized by the sol–gel method and characterized using X-ray diffraction, thermogravimetry-mass spectrometry, atomic absorption spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis and nitrogen physisorption. The non-calcined material was active as a catalyst in transesterification reactions and
Marciniuk, Leticia L., Hammer, Peter, Pastore, Heloise O., Schuchardt, Ulf, Cardoso, Dilson   +4 more
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Basic catalysts and fine chemicals

1993
Abstract Catalytic behaviors of solid base catalysts for fine chemicals synthesis as well as the fundamental reactions are described. The reactions included are double bond isomerization of olefins, addition of hydrogen and amines to conjugated dienes, dehydration, dehydrogenation, reduction, alkylation, aldol addition and condensation, Wittig-Horner
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Electrochemical Activation of Molecular Catalysts: From Basics to Applications

2018
In this article, the fundamental concepts of redox catalysis are first presented. While the one electron scheme provides general guidelines, it needs to be adapted when more complex systems involving several chemical reactions and electron transfer are concerned.
Fillaud, Laure, Maisonhaute, Emmanuel, Fave, C., Robert, M.   +3 more
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Basic evidences for methanol-synthesis catalyst design

Catalysis Today, 2009
A series of Cu-ZnO/ZrO2 catalysts (Znat/Cuat, 0-3; ZrO2, 42-44 wt.%) with markedly improved total (SA, 120-180 m2/g) and metal surface area (MSA, 9-63 m2/g) has been synthesized via the reverse coprecipitation under ultrasound field. Structure, adsorption properties and surface reactivity were probed by BET, XRD, TPR, N2O-titration and TPD measurements
F Arena, G Italiano, K Barbera, G Bonura, L Spadaro, F Frusteri   +5 more
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Tetrahedral boronates as basic catalysts in the aldol reaction

Zeitschrift für Naturforschung B, 2015
Abstract β-Hydroxyketones are versatile building blocks in organic synthesis, which can be conveniently synthesized from ketones and aldehydes by aldol reactions. Unfortunately, these reactions often suffer from dehydration of the initially formed β-hydroxyketones.
Tobias Müller, Kristina Djanashvili, Joop A. Peters, Isabel W.C.E. Arends, Ulf Hanefeld   +4 more
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