Catalytic Activity of Intermetallic Compounds in the Gas Phase Reduction of Nitrobenzene.

1939 ◽  
Vol 43 (6) ◽  
pp. 805-807
Author(s):  
O. W. Brown ◽  
J. B. Borland ◽  
R. A. Johnston ◽  
R. C. Grills
Keyword(s):  
Catalytic Activity ◽  
Gas Phase ◽  
Intermetallic Compounds ◽  
Phase Reduction

The effect of partial exchange of sulphonated macroporous styrene-divinylbenzene copolymers for different ions on their catalytic activity

1981 ◽  
Vol 46 (10) ◽  
pp. 2354-2363 ◽  
Author(s):  
Svatomír Kmošták ◽  
Karel Setínek
Keyword(s):  
Catalytic Activity ◽  
Transition Metal ◽  
Metal Ions ◽  
Gas Phase ◽  
Transition Metal Ions ◽  
Exchange Capacity ◽  
Total Exchange Capacity ◽  
Styrene Divinylbenzene ◽  
Na Ions ◽  
Type Of Transition

The catalytic activity of sulphonated macroporous styrene-divinylbenzene copolymers, the exchange capacity of which was neutralized from 30, 50 and 80% by Fe(III) ions and from 30% by Na ions and that of Wofatit Y-37 ion exchanger neutralized from 10% of its total exchange capacity by several transition metal ions and by sodium has been studied in isomerisation of cyclohexene and dehydration of 1-propanol in the gas phase at 130 °C. It was demonstrated that in both reactions transition metal ions exhibit additional effect to the expected neutralization of the polymer acid groups. In the case of cyclohexene isomerization, this effect depends on the degree of crosslinking of polymer mass of the catalyst. Such dependence has not been, however, observed in dehydration of 1-propanol. The type of transition metal ions did not exhibit any significant effect on the catalytic activity of the polymer catalysts studied.

scholarly journals Study of deactivation in mesocellular foam carbon (MCF-C) catalyst used in gas-phase dehydrogenation of ethanol

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yoottapong Klinthongchai ◽  
Seeroong Prichanont ◽  
Piyasan Praserthdam ◽  
Bunjerd Jongsomjit
Keyword(s):  
Catalytic Activity ◽  
Pore Size ◽  
Gas Phase ◽  
Surface Area ◽  
Active Sites ◽  
Operating Temperature ◽  
Coke Formation ◽  
Ethanol Conversion ◽  
Deactivation Of Catalyst ◽  
Dehydrogenation Of Ethanol

AbstractMesocellular foam carbon (MCF-C) is one the captivating materials for using in gas phase dehydrogenation of ethanol. Extraordinary, enlarge pore size, high surface area, high acidity, and spherical shape with interconnected pore for high diffusion. In contrary, the occurrence of the coke is a majority causes for inhibiting the active sites on catalyst surface. Thus, this study aims to investigate the occurrence of the coke to optimize the higher catalytic activity, and also to avoid the coke formation. The MCF-C was synthesized and investigated using various techniques. MCF-C was spent in gas-phase dehydrogenation of ethanol under mild conditions. The deactivation of catalyst was investigated toward different conditions. Effects of reaction condition including different reaction temperatures of 300, 350, and 400 °C on the deactivation behaviors were determined. The results indicated that the operating temperature at 400 °C significantly retained the lowest change of ethanol conversion, which favored in the higher temperature. After running reaction, the physical properties as pore size, surface area, and pore volume of spent catalysts were decreased owing to the coke formation, which possibly blocked the pore that directly affected to the difficult diffusion of reactant and caused to be lower in catalytic activity. Furthermore, a slight decrease in either acidity or basicity was observed owing to consumption of reactant at surface of catalyst or chemical change on surface caused by coke formation. Therefore, it can remarkably choose the suitable operating temperature to avoid deactivation of catalyst, and then optimize the ethanol conversion or yield of acetaldehyde.

Proof of the Catalytic Activity of a Naked Metal Cluster in the Gas Phase

1992 ◽  
Vol 31 (5) ◽  
pp. 636-638 ◽  
Author(s):  
Patrick Schnabel ◽  
Konrad G. Weil ◽  
Manfred P. Irion
Keyword(s):  
Catalytic Activity ◽  
Gas Phase ◽  
Metal Cluster

MFI-type zeolite nanosheets for gas-phase aromatics chlorination: a strategy to overcome mass transfer limitations

RSC Advances ◽  
2014 ◽  
Vol 4 (52) ◽  
pp. 27242-27249 ◽  
Author(s):  
Marilyne Boltz ◽  
Pit Losch ◽  
Benoit Louis ◽  
Guillaume Rioland ◽  
Lydie Tzanis ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Catalytic Activity ◽  
Gas Phase ◽  
Zeolite Crystal ◽  
Silanol Groups ◽  
Type Zeolite

Mass transfer limitations and catalytic activity were studied for various ZSM-5 zeolite crystal sizes in the chlorination of deactivated arenes. An estimation of the quantity of mild acidic external silanol groups of zeolite nanosheets was made.

scholarly journals Gas phase synthesis of dimethyl carbonate from CO2 and CH3OH over Cu-Ni/AC. A kinetic study

2019 ◽  
pp. 88-99 ◽  
Author(s):  
Oscar Felipe Arbeláez-Pérez ◽  
Sara Dominguez Cardozo ◽  
Andrés Felipe Orrego-Romero ◽  
Aida Luz Villa Holguin ◽  
Felipe Bustamante Londoño
Keyword(s):  
Carbon Dioxide ◽  
Catalytic Activity ◽  
Activated Carbon ◽  
Gas Phase ◽  
Dimethyl Carbonate ◽  
Direct Synthesis ◽  
Dispersion Analysis ◽  
Molar Ratio ◽  
Rate Determining Step ◽  
Carbonate Formation

The catalytic activity for dimethyl carbonate formation from carbon dioxide and methanol over mono and bimetallic Cu:Ni supported on activated carbon is presented. Bimetallic catalysts exhibit higher catalytic activity than the monometallic samples, being Cu:Ni-2:1 (molar ratio) the best catalyst; X-Ray diffraction, transmission electron microscopy, and metal dispersion analysis provided insight into the improved activity. In situ FT-IR experiments were conducted to investigate the mechanism of formation of dimethyl carbonate from methanol and carbon dioxide over Cu-Ni:2-1. The kinetics of the direct synthesis of dimethyl carbonate in gas phase over Cu:Ni-2:1 supported on activated carbon catalyst was experimentally investigated at 12 bar and temperatures between 90 oC and 130 oC, varying the partial pressures of CO2 and methanol. Experimental kinetic data were consistent with a Langmuir–Hinshelwood model that included carbon dioxide and methanol adsorption on catalyst actives sites (Cu, Ni and Cu-Ni), and the reaction of adsorbed CO2 with methoxi species as the rate determining step. The estimated apparent activation energy was 94.2 kJ mol-1.

An Ni–P/C electro-catalyst with improved activity for the carbohydrazide oxidation reaction

RSC Advances ◽  
2016 ◽  
Vol 6 (94) ◽  
pp. 91956-91959 ◽  
Author(s):  
Xinyue Cao ◽  
Haining Wang ◽  
Shanfu Lu ◽  
Sian Chen ◽  
Yan Xiang
Keyword(s):  
Catalytic Activity ◽  
Liquid Phase ◽  
Oxidation Reaction ◽  
Reduction Method ◽  
Significant Enhancement ◽  
Phase Reduction ◽  
Electro Catalytic Activity

Ni–P/C NPs were prepared through a two-step liquid phase reduction method, which exhibited a significant enhancement for the electro-catalytic activity towards the carbohydrazide oxidation reaction compared with Ni/C NPs.

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