Catalytic Activity of Iron on ZSM-5 Zeolite Support Prepared from Lignite Fly Ash for CO2 Hydrogenation

ZSM-5 zeolite catalysts prepared from fly ash (58.6 wt% purity) and impregnated with iron, i.e., 6 wt% Fe/ZSM-5, 9 wt% Fe/ZSM-5, and 12 wt%Fe/ZSM-5, were tested for C02 hydrogenation to convert C02 to hydrocarbon compounds. The C02/H2 reactant gas mixture with a mole ratio of 1: 1.5 was fed into a packed bed reactor with a flow rate of 50 cm3(STP)/min. The operating temperatures were 350, 400, 450 and 500°C and pressure was 10 atm. The results show that the highest yield of hydrocarbon products was obtained at 450°C for all tested catalyst. Compared with ZSM-5 catalyst without iron loading, ZSM-5 zeolite catalysts loaded with iron produced more hydrocarbon products with high number of carbon atom and also olefinic compounds. In this study, the highest percentage selectivity of hydrocarbon products was obtained from 12 wt% Fe/ZSM-5 with 51.0,20. 1,0.9,3.9, 1. I and I.I % of CO, CH4, C2H4, C2H6, C3H6, and C3H8 respectively.