Effect of Several Anions on Fe-Based Catalyst for Fischer-Tropsch Synthesis

The influence of several anions on Fe-based Fischer-Tropsch catalyst, used in the synthesis of light olefins from synthesis gas, was studied. The results indicated that the addition of anions resulted in the reduction of catalytic activity. When the anion content in the catalyst was 500 ppm, the influence of different anions on the catalysis activity was as follows: S2−> Cl– > SO2−4 >NO−3. The addition of S2− improved the selectivity of total hydrocarbons in the products, and Cl− reduced this selectivity but increased the olefin content in the total hydrocarbons at the same time. When the contents of S2− and Cl− in the catalyst were less than 50 ppm, their influence could be ignored. The XRD results indicated that the addition of anions reduced the contents of α-Fe and Fe3C, which were the active components in the catalyst.