Preparation and Performance of Supported Iron-based Catalysts for Conversion of Synthesis Gas to Light Olefins

The supported iron-based catalysts for the conversion of synthesis gas to light olefins were prepared by impregnation method and the effects of parameters, such as carrier, promoter, calcination temperature, reaction temperature, reaction pressure and space velocity, on the reaction were investigated in a fixed-bed reactor.The catalysts were characterized by XRD, N2 physisorption, thermo gravimetric analysis and Raman spectroscopy.The results indicated that FeK/ZSM-5 catalyst prepared by calcination at 500℃ after 3 h had the best catalytic activity.Increasing reaction pressure and decreasing space velocity, the activity of catalyst was all obviously improved.Using ZSM-5 as the carrier, the comparable catalytic performance of adding K and Mn promoters were studied.The results showed that FeMnK/ZSM-5 catalyst improved the CO conversion rate from 18.7% to 63.8%, and C2=～C3= selectivity from 4.8% to 14.1% contrast to Fe/ZSM-5 catalyst under the conditions of volume ratio of H2 to CO2, reaction temperature 380℃, reaction pressure 1.0 MPa and space velocity 4400 h-1.