Influence of sub-stoichiometric sorbitol addition modes on the structure and catalytic performance of alumina-supported cobalt Fischer–Tropsch catalysts

This paper focuses on the influence of different modes of sub-stoichiometric addition of sorbitol during catalyst preparation on the structure and performance of alumina-supported cobalt catalysts in Fischer–Tropsch synthesis. The catalysts are prepared using either alumina support pretreated with sorbitol or using co-impregnation of alumina support or using co-impregnation of calcined cobalt catalyst or catalyst post-treatment with sorbitol. It is found that the catalyst structure and catalytic performance are strongly affected by sorbitol addition mode. The catalysts prepared using support pretreatment with sorbitol or sorbitol addition during first impregnation step display an enhanced cobalt dispersion which is accompanied by a spectacular increase in Fischer–Tropsch reaction rate and hydrocarbon productivity.