Study of Carbon Dioxide Hydrogenation to Hydrocarbons Over Iron-Based Catalysts: Synergistic Effect

Hydrogenation of CO2 to CO and hydrocarbons is carried out over a wide range of catalysts. Group of VIIIB transition metals have proved high conversion and selectively for CO and methane. Meanwhile, low cost and effective catalysts are preferable in an industrial scale. In this work, the synergistic effect of iron content on the catalytic performance were investigated in carbon dioxide hydrogenation reaction. Incipient wetness impregnation procedure was used for the preparation of four gamma-Al2O3 supported iron-based catalysts. BET, XRD, H-2-TPR and TEM techniques were employed for the catalyst characterization. The evaluation of catalysts were carried out in a fixed bed reactor at the process conditions of temperature of 300 degrees C, pressure of 20 atm, H-2 to CO2 ratio of 3 and GHSV of 3 NL/(h g(Cat)). It was found that the promoter addition improves the activity of Fe catalyst for both Fischer-Tropsch synthesis (FTS) and Reverse Water Gas Shift (RWGS) reactions. The results showed that conversion of CO2 was from 15.6 to 35.6% with major products of methane, C-2 to C-4, C-5+ and CO. It was also found that impact of K and Ce promoters into iron catalyst showed the highest conversion and hydrocarbon yield due to the synergistic effect.