Review of iron-based catalysts with and without zeolite supports used in fischer-tropsch processes

Iron is a favored catalyst for Fischer-Tropsch (FT) synthesis, the production of hydrocarbons from synthesis gas. Zeolites are common catalysts for hydrocarbon processing. Here we review iron-based catalysts for FT, both alone and in combination with zeolites. The importance of the related water-gas-shift reaction (WGS) in specifying a FT catalyst is studied. For the iron-based catalyst, the effects of different catalyst supports are explained. The performance of such a catalyst when various metal promoters (Cu, K, Mo, and others) are added to it are compared. Several metal promoters on a Fe-based catalyst increase FT and WGS water-gas shift reaction activity, and also improve the stability of the catalyst. For the zeolite catalyst, changes in the final product profile with change in zeolite type are described. Zeolites are used to convert long-chain hydrocarbons produced by the FT process into gasoline- and diesel-range hydrocarbons. Zeolite use in optimization of olefin, aromatic, and branched products and conversion of oxygenates to hydrocarbons is explained based on several studies. Deactivation and the overall reaction sequence on zeolite catalysts are described.