Supported catalysts genesis

Recent research on the elementary steps during preparation of zeolite-supported metals has helped to understand the genesis of these particles in considerable detail. For the best studied systems the goal of preparing catalysts by design has been achieved (69-77). 

Adsorption and decomposition of NO were investigated by using the IR cell itself. NO was adsorbed at room temperature on self-supported wafers pressed from the catalyst candidates. Prior to adsorption, the sample was outgassed at 723 K in vacuum. IR spectra were run on a Matson Genesis FTIR spectrometer. 

Z,R, Ismagilov, D,A. Arendarskii and O.A. Kirichenko. Investigation of catalysts and reaction of catalytic combustion, IV Genesis of the phase composition of supported oxide aiuminiura-copper-chromium catalysts, Kinet, Ratal., 30 (4) (1989) 918-926. 

The capacity of carbon support for behaving as a gas electrode and the ability of dissolved or supported metal ions, as well as the metal particles, to interact with the carbon surface through a charge transfer indicate the considerable influence of the atmosphere composition and of electrophysical properties of the carbon (the latter are determined both by the surface and hulk properties of the carbon matrix) on genesis of the supported metal catalysts. Surprisingly few papers deal with these aspects of scientific basis for preparation of Me/C catalysts. Undoubtedly, this gap should be bridged in the near future. 

Silica-supported Ru catalysts present specific problems in that ruthenium oxides are mobile on silica. The approach used here avoids this problem by crating insitu-formed supported Ru organo complexes. The genesis of the Ru complex formation can be followed fiom the thermal... 

The platinum group metals demonstrate clearly the impact of the key parameters that influence the efficiency of ammonia synthesis catalysts structure sensitivity, the heat of adsorption of reactants and products, and the roles of promoters and supports. The key requirement to minimize the activation energy for nitrogen dissociation limits the active metals to alkali-promoted ruthenium and osmium. Similar activities are then obtained, irrespective of the genesis of the alkali metal promoter (salt or metal), indicating that both convert to a similar... 

P.A. Chemavskii, A. Y. Khodakov, G. V. Pankina, J.-S. Girardon, E. Quinet., 2006, In situ characterization of the genesis of cobalt metal particles in silica-supported Fischer-Tropsch catalysts using Foner Magnetic method, Appl. Catal. A Gen, 306,108-119. 

Despite the wide application irtilch supported metal catalysts have foimd in industry and fundamental researches, knowledge on their genesis is still rather limited and is especially poor for the catalysts based on carbon siQ>ports. In part it is caused by a secretive character of most works in the field of catalyst manufacture. In addition, carbon siq>ports prepared from natural polymeric substances, such as coal or wood, were mainly used so far, with the texture, ash content and kind of admixtures being variable from batch to batch this makes comparison and interpretation of published results difficult. 

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