Cobalt-aluminium Oxide Catalysts for Transformation of CO and H2 in Fischer – Tropsch Syntheses

Abstract

Properties of cobalt-aluminium catalysts for the Fischer – Tropsch synthesis were studied to identify conditions for the catalyst preparation and activation that would allow the reduction temperature to be lowered and the catalyst performance to be improved. It was shown that an increase in the ratio of NO – 3 /СО 2– 3 – anions to ca. 1,9–3,1 in the hydroxo-nitrate-carbonate precursors of the said catalysts favors a decrease in the temperature of reduction of cobalt cations in oxide precursors. Adsorption properties of the cobalt metal particles formed at different temperatures of the reduction of the oxide samples were studied to show that the catalyst activation at 500 °C is preferable for the formation of disperse particles of Co 0 . In the Fischer-Tropsch reactions with mixtures CO:H 2 :N 2 = 30:60:10 vol.% at T = 210 °C and P =2,1 MPa, the catalysts reduced at 500 °C demonstrate a high efficiency comparable with the efficiency of commercial Co-containing catalysts (ca. 0,34 g CH /(g cat· h)).