Cooperative effect of cobalt and zeolite in controlling activity and stability of a catalytic Fischer–Tropsch process

Abstract

The use of zeolites in Co-catalysts of Fischer-Tropsch synthesis (FTS) results in cooperative effect in the form of sudden increase of the zeolite activity in catalysing secondary transformations of FTS-generated hydrocarbons at unusually low temperatures in the range of 170-260 °C. In addition, hydrophobic zeolites in H-form allow changing the hydrophobicity of the pore walls and influence capillary condensation phenomena for intermediate species. The most unexpected effect of Co and hydrophobic zeolites is the improvement of degradation behaviour of the catalysts due to involvement of FTS-generated water into formation of additional Bronsted centres thus preventing undesirable oxidation of heat-conductive metal additives and other water-induced degradation processes. In addition, the stability of catalyst behaviour and its lifetime increase.