Fischer-tropsch synthesis using promoted, unsupported, supported, bimetallic and spray-dried iron catalysts: A review

The Fischer-Tropsch synthesis (F-TS) is a catalytic-polymerization reaction that produces hydrocarbons for fuel and chemicals, by reacting synthesis gas (CO + H₂) using a transition metal catalyst (Fe or Co). Iron-based F-TS can produce C2-C4 and C5-C11 hydrocarbons which are important for the production of chemicals and fuel in industry. The difficulty in developing the F-TS process is to control reaction conditions to decrease C1 selectivity while increasing the C5 + hydrocarbons. Iron-based catalysts are cheap and insensitive to sulfur compounds compared to cobalt catalysts. This review highlights the use of unsupported iron catalysts and the effect of process conditions and preparation methods in the selectivity of C1, C2-C4, and C5+ / C5-C11 via F-TS. The review further discusses the effect of various promoters, bimetallic catalysts and supports to improve catalyst properties with a specific focus on the spray-drying technology as a mechanism to decrease the deactivation of the catalysts with good attrition resistance.