Role of zeolite in the synthesis of liquid hydrocarbons from CO and H2 on a composite cobalt catalyst

Abstract

It is found that the main role of zeolite in Fischer–Tropsch synthesis on a composite Co catalysts is to reduce the average molecular weight of hydrocarbons produced from CO and H2 on acid sites. Secondary transformations of hydrocarbons on zeolites seem to occur via a carbocation mechanism. The total composition of synthesis products depends on the zeolite properties and the mutual arrangement of zeolite and cobalt active sites. It is shown that in some cases, introducing H-form zeolite into the Co catalysts for Fischer–Tropsch synthesis increases the productivity and the selectivity to synthetic oil and lowers the selectivity to methane.