Effect of process conditions on the product distribution of Fischer–Tropsch synthesis over a Re-promoted cobalt-alumina catalyst using a stirred tank slurry reactor

Abstract

The effects of process conditions on Fischer–Tropsch synthesis (FTS) product distribution were studied using a 1-L stirred tank slurry reactor and a 0.48%Re–25%Co/Al2O3 catalyst. It was found that the chain growth probability of C1 intermediate (α1) has the most dominant effect on CH4 and C5+ selectivity. α1 was found to be highly dependent on process conditions. Relatively constant values of C2+ growth probabilities with reactor residence time, as well as other process variables, suggest that 1-olefin readsorption has a minor effect on product selectivities. A low value of α1 and its different response to variations in process conditions, compared to higher chain growth probabilities, seems to support a hypothesis that a higher-than-expected yield of methane is caused by at least two separate methane formation pathways. Understanding these pathways and ways to suppress excess methane formation is a key factor in obtaining higher C5+ selectivity.