Milos Ralek

The Fischer-Tropsch Synthesis in the Liquid Phase

Abstract The hydrogenation of carbon monoxide by the Fischer-Tropsch (F-T) process [1] forms saturated and unsaturated compounds of the homologous hydrocarbon series. It permits the synthesis of hydrocarbons ranging from methane to high-melting paraffins with molecular weights above 20,000, depending on the catalyst, temperature, and type of process employed. By-products such as alcohols, aldehydes, ketones, acids, and esters are formed on a smaller scale. Small amounts of aromatic compounds are formed at high temperatures by secondary dehydrocyclization reactions from the primary hydrocarbons formed.

On the relevance of mass transfer limitations in the Fischer-Tropsch slurry process

Abstract Satterfield and Huff[1] reported recently on significant mass transfer resistances in the FT slurry process. However, their conclusions are at least partly based on a study with an unsuitable catalyst. In the present communication FT studies with 8 different catalysts and bubble columns, respectively, were analyzed using new and reliable results on hydrodynamic properties. In all cases, mass transfer resistances were found to be small compared to reaction resistances. As long as much more active catalysts are not developed significant mass transfer limitations cannot be expected in the bubble column if operated under appropriate conditions. The absence of mass transfer limitations is mainly a result of the high gas holdups attainable with molten paraffin as liquid phase.