Catalytic performance of Iron-based catalyst in Fischer–Tropsch synthesis using CO2 containing syngas

Abstract This paper focuses on the catalytic performance of iron-based catalyst in Fischer–Tropsch Synthesis (FTS) using CO 2 containing syngas. The catalysts were prepared by incipient wetness impregnation method of silica with solution of iron nitrate followed by calcination in air. Physical and chemical properties of iron-based catalyst were carried out using N 2 adsorption-desorption, H 2 -TPR, CO-TPR and TPH. The catalysts were tested in Fischer–Tropsch conditions (T = 220°C, P = 1 bar, GHSV = 300 h -1 , H 2 /CO x = 0.5). The results show that iron-based catalyst activated by CO is more active for hydrogenation than the catalyst activated by H 2 . The activation of iron-based catalyst by CO provides iron carbide combining with iron oxide which was reduced partially. Fe 3 O 4 (partial reduced iron oxide) is expected to be exist in the iron-based catalyst pretreated by CO. This oxide phase allows the conversion of CO 2 to CO through the reverse water-gas-shift (RWGS) reaction. Thus, iron-based catalyst activated by CO is a candidate catalyst for FTS using CO 2 containing syngas. Fe 3 O 4 enhances RWGS activity while iron carbide is effective for the hydrogenation. The different product distributions of H 2 -CO, H 2 -CO 2 and H 2 -CO-CO 2 mixtures are due to the different reaction pathway of CO and CO 2 . The key of reaction pathway is the active site generated from pretreatment method.