Results 171 to 180 of about 1,079 (210)

Characterization of copper chromite catalysts for methanol dehydrogenation

Applied Catalysis, 1984
Abstract Copper chromite catalysts have been characterised by total and metal surface areas. X-ray powder diffraction, thermal gravimetric analysis and selective extraction of copper oxide in order to investigate the nature of the active catalyst for methanol dehydrogenation.
S.P. Tonner, M.S. Wainright, D.L. Trimm, N.W. Cant   +3 more
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Sintering of lanthanum chromite doped with zinc or copper

Journal of Materials Science Letters, 1988
La substitution de Zn ou Cu a Cr dans LaCrO 3 permet l'obtention de ceramiques denses sans controle de la pression d'oxygene lors du ...
Shinsuke Hayashi, Kenji Fukaya, Hajime Saito   +2 more
openaire   +1 more source

A study of the preactivation of a copper chromite catalyst

Catalysis Letters, 1994
Copper chromite was studied for the reductive alkylation of aniline with acetone to N-isopropylaniline as a function of the catalyst prereduction conditions. In order to optimize prereduction conditions the catalyst was reduced in an atmosphere of hydrogen at different temperatures: 100, 150, 200, 250, 300, 350, 400 and 450°C and for different ...
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The nature of hydrogen stabilization in the reduced copper chromites

Journal of Molecular Catalysis A: Chemical, 1996
Abstract In situ powder X-ray and neutron diffraction showed that copper chromite retains its spinel structure (space group Fd3m, a = 8.348(3) A ) in hydrogen at 320°C. The spinel has a copper ion deficiency and is stabilized by the dissolved hydrogen.
L.M. Plyasova, L.P. Solovyeva, T.A. Krieger, O.V. Makarova, T.M. Yurieva   +4 more
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Nanometer size copper particles in copper chromite catalysts

1995
Publisher Summary It is difficult to obtain copper in atomic state on the surface of an oxide catalyst. Therefore, the task of achieving metallic copper with a large surface area becomes crucial. Highly dispersed copper can be obtained on the surface via the reduction of copper-containing oxides.
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Properties of Copper Chromite Catalysts in Hydrogenation Reactions

Journal of Catalysis, 1997
Abstract A pretreatment involving a 4-h reduction under H2at 573 K, compared to either 473 or 673 K, gave the highest specific activity for furfural and crotonaldehyde hydrogenation over an unpromoted copper chromite catalyst. Both H2and CO chemisorption declined monotonically with increasing reduction temperature, but turnover frequencies also ...
R. Rao, A. Dandekar, R.T.K. Baker, M.A. Vannice   +3 more
openaire   +1 more source

Electron Microscopy of Barium-Promoted Copper Chromite

Proceedings, annual meeting, Electron Microscopy Society of America, 1985
Copper chromite was reported as an effective catalyst for the hydrogenation of esters to alcohols by Homer Adkins in 1931, and it still remains the catalyst of choice for this reaction. Its most common commercial application is in the hydrogenation of fatty esters to detergent range linear alcohols.
J. B. Hall, J. K. Kouba
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Composite propellent catalysts: Copper chromate and chromite

Combustion and Flame, 1970
The thermal decomposition of copper chromate and chromite has been examined by simultaneous thermogravimetric analysis and differential thermal analysis. The successive stages in the decomposition of the two compounds have been identified, and it has been shown that both ultimately yield cuprous chromite and cuprous oxide.
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Crystal Distortion in Copper Ferrite-Chromite Series

Journal of the Physical Society of Japan, 1961
The cation distributions in copper ferrite-chromite series and the copper ferrite quenched from high temperatures are measured by X-ray diffraction method. The lattice parameters are also measured as a function of chromium ion content and of temperature.
Haruyuki Ohnishi, Teruo Teranishi
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Synthesis and Characterization of Magnesium Copper Chromite Spinels

International Journal of Scientific Research, 2012
Various composition of copper magnesium chromite spinels (Cu1-x MgxCr2O4 with x=0, 0.25, 0.5, 0.75, 1.0) were synthesized by co-precipitation method. The catalysts were characterized by various Physico-chemical methods XRD, nitrogen adsorption studies, FT-IR spectroscopy, Thermogravimetric analysis (TG), UV-DRS and Temperature Pro- grammed Desorption ...
Reni George, Sankaran Sugunan
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