A promising composite bimetallic catalyst for producing CH4-rich syngas from bitumite one-step gasification

Abstract

In this study, a novel catalyst of composite Fe1Mn1-Fe1Ni3-CaO was initially designed and prepared for one-step gasifying Meihuajing coal (MHC, a bituminous coal) to produce CH4-rich syngas using a pressurized fix-bed reactor, followed by optimizing conditions for MHC catalytic gasification by response surface methodology. The bimetallic Fe-Mn catalyst and Fe-Ni catalyst mainly acted to catalyze the reactions of MHC gasification and non-condensable methanation, respectively. A remarkable synergistic effect was observed for the formation of CH4 and CH4-rich syngas using the Fe-Mn catalyst, which was closely related to the formation of MnFe2O4 during MHC gasification. CaO was mixed with the Fe1Mn1 component to further improve the CH4 yield by promoting the reaction of MHC and H2O(g). Using Fe1Mn1-Fe1Ni3-CaO with a mass ratio of 1:1:1 as the catalyst, a higher productivity of 0.175 L/(g coal) was achieved from MHC catalytic gasification at a temperature of 750 °C, a pressure of 4.40 MPa, and a steam inflow of 1.20 g/min.