Cobalt-based Fischer-Tropsch synthesis carbon

Moodley, D. J., van de Loosdrecht, J., Saib, A. M., Overett, M. J., Datye, A. K., and Niemantsverdriet, J. W. 2009. Carbon deposition as a deactivation mechanism of cobalt-based Fischer-Tropsch synthesis catalysts under reahstic conditions. Appl. Catal. A, 354 102-10. 

Fischer-Tropsch synthesis can be regarded as a surface polymerization reaction since monomer units are produced from the reagents hydrogen and carbon monoxide in situ on the surface of the catalyst (usually based on iron or cobalt). Hence, various hydrocarbons (mainly n-paraffins) are formed by successive addition of Ci units to growing chains on the catalyst surface. The main reaction of Fischer-Tropsch synthesis is therefore represented by ... 

Fischer-Tropsch (FT) synthesis is a catalysed chemical reaction in which carbon monoxide (CO) and hydrogen (H2) are converted into liquid hydrocarbons of various forms. Typical catalysts used are based on iron (Fe) and cobalt (Co). The production of liquid hydrocarbons using FT synthesis is a well known process. It was invented by Franz Fischer and Hans Tropsch in the 1920s in Germany. It follows the reaction ... 

The oxo reaction (31) is carried out in the liquid phase at high pressure using a cobalt catalyst. A mixture of aldehyde isomers is always produced, each isomer being one carbon number higher than the starting olefin. As a group the oxygenated products of the hydrocarbon synthesis (Fischer-Tropsch) process and the oxo process are primary compounds and thus (except, of course, the methyl and ethyl derivatives) differ fundamentally from the products based on alcohols made by the hydration of olefins, which are always secondary or tertiary in structure. 

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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