Cobalt-carbon monoxide adsorption

Wesner, D. A., Linden, G., and Bonzel, H. P. 1986. Alkali promotion on cobalt Surface analysis of the effects of potassium on carbon monoxide adsorption and Fischer-Tropsch reaction. Appl. Surf. Sci. 26 335-56. 

A systematic attempt to correlate the catalytic effect of different surfaces with their adsorptive capacity was made by Taylor and his collaborators. Taylor and Burns, for example, investigated the adsorption of hydrogen, carbon dioxide, and ethylene by the six metals nickel, cobalt, palladium, platinum, iron, and copper. All these metals are able to catalyse the hydrogenation of ethylene to ethane, while nickel, cobalt, and palladium also catalyse the reduction of carbon monoxide and of carbon dioxide to methane. 

Catalyst Characterization. Chemical analyses, x-ray diifraction analyses, and gas adsorption procedures were used to characterize the composition, crystallographic character, and surface structure of the nickel and cobalt zeolite catalyst preparations. The chemical and x-ray procedures were standard methods with the latter described elsewhere 11). Carbon monoxide chemisorption measurements provide useful estimates of the surface covered by nickel atoms from the zeolite substrate 10). 

Experimental Values of the Heats of Adsorption of Carbon Monoxide, Carbon Dioxide, and Oxygen in kcal./mole on Surfaces of Copper, Nickel, and Cobalt Oxide in Different States of Pretrecumenl... 

Other Syntheses Related to the Fischer-Tropsch Process Comparatively little is yet known of some synthetic reactions which obviously resemble the Fischer-Tropsch process very closely, but they are worth brief mention because they are also likely to be controlled by geometrical factors. The Oxo synthesis (15) of aldehydes by the interaction of ethylene or other olefins with carbon monoxide and hydrogen is carried out in contact with cobalt catalysts at temperatures in the range 110-150°, and under a pressure of 100-200 atmospheres. Cyclic olefins react similarly for example, cyclohexene gives hexahydrobenzaldehyde. There can be little doubt that a two-point adsorption of the hydrocarbon must take place and that the adsorbed molecule then reacts with carbon monoxide and hydrogen the difference between this process and that responsible for the normal hydrocarbon synthesis is that adsorbed carbon monoxide survives as such under the less drastic temperature conditions which are employed. Owing to the fact that a variety of isomeric aldehydes are produced, this system deserves further detailed study on geometrical lines. 

The Pauson-Khand reaction has also been carried out under different conditions, such as the use of chiral ligands, including PuPHOS, CamPHOS, and camphorsultam the use of aldehydes as the carbon monoxide source > the use of solid-supported cobalt catalyst to enhance purification, such as the dry-state adsorption the use of colloidal cobalt nanoparticle and the use of metallic cobalt supported on mesoporous silica prepared by decomposing Co2(CO)8 on mesoporous silica supports (SBA-15 and MCM-41) in the refluxing toluene solution.Other modifications include different promoting methods, such as photo-irradiation, microwave irradiation, molecular sieves, TEMPO,A-oxides, and supercritical fluids. Furthermore, the cycloaddition between allene and carbon monoxide under similar conditions is known as the allenic Pauson-Khand reaction,27,41 jjjg reaction among alkyne, carbodiimide, and CO is referred to as the aza-Pauson-Khand reaction. ... 

The reaction is done with a metal catalyst. Catalysts based upon iron or cobalt have been used commercially for hydrocarbon synthesis [5], The mechanism involves adsorption of hydrogen and carbon monoxide on the metal surface [6]. The Fischer-Tropsch process enables natural gas to be converted to liquid synthetic fuel. First, the natural gas is oxidized to syn gas which is then converted by the Fischer-Tropsch process to the liquid hydrocarbon mixture, which is useful as fuel. 

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