CO Cleavage and Reduction

In the Fischer-Tropsch (F.T.) synthesis, a mixture of CO and Hj (synthetic gas or syngas), which is produced by burning coal and other carbonaceous materials in the presence of oxygen and steam, is converted into a wide range of hydrocarbon and oxygen-containing products. Since the finding by Fischer and Tropsch in 1923, various supported metals such as Fe, Ru, Co, Rh, Ir, Ni, Pd, and Pt have been examined as catalysts.  

In recent years homogeneous systems containing organometallic compounds, especially metal carbonyl clusters as catalysts have been investigated very actively with the aim of selectivity improvement and mechanism elucidation. 

Of the three main mechanisms proposed for the heterogeneous F.T. synthesis of hydrocarbons, the following carbide-methylene mechanism is most widely used  

Upon chemisorption on a metal catalyst the CO molecule dissociates into carbon and oxygen atoms. The surface carbide thus produced is hydrogenated successively to CH, entities, which then link up to afford the products.  

Isolation and characterization of intermediates are much easier for the homogeneous reactions of organometallic compounds than for similar 

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