An investigation into the Fischer-Tropsch synthesis over supported ruthenium in a stirred gas-solid reactor.

Abstract

A stirred gas-solid reactor has been used to study the Fischer-Tropsch synthesis over a supported ruthenium catalyst. Detailed catalyst characterisations were conducted on both fresh and used catalyst samples and included such techniques as physisorption and chemisorption, electron microprobe examination, carbon determination and mercury porosimetry. The product obtained from the synthesis consisted largely of n-alkanes and the product selectivity of individual carbon number fractions is demonstrated to have certain advantages over the corresponding selectivities (adapted from the literature) obtained over iron, cobalt and molybdenum catalyst. The rate data obtained is fitted to two empirical models: a simple power law model and a previously-described mechanistic model. Energies of activation for methanation and carbon monoxide removal (at approximately 34,3 and 19 kcal/mol respectively) are compared with regressed values obtained by other workers. Rate data for the synthesis of higher hydrocarbons are fitted to a simple power law model and energies of activation for individual carbon number fractions up to C8 are presented.