Investigation of H2O and CO2 Reforming and Partial Oxidation of Methane: Catalytic Effects of Coal Char and Coal Ash

Abstract

Methane reforming and partial oxidation was studied to evaluate the catalytic effects of coal chars and coal ashes on methane (CH4) conversion, sum selectivity (the sum of H2 and CO), and ratio selectivity (the ratio of H2/CO) in an atmospheric fluidized bed. The kinetics study presented the possibility of CH4 reforming and partial oxidation with a favorable H2/CO ratio, greater than 5. The higher H2/CO ratio in CH4 reforming and the partial-oxidation process can reduce the consumption of CH4 needed to adjust the H2/CO ratio during combined coal gasification and methane reforming. Coal ashes failed to be good candidates of catalysts on CH4 reforming and partial oxidation because of their very low specific surface area available for catalytic reactions. However, coal chars presented very promising catalytic performance on CH4 reforming and partial oxidation because of their larger specific surface area. In this study, no other constituents in coal fly ash or special surface properties of coal chars were correlated with the enhanced methane-conversion efficiency. It seems that the specific surface area is only variable in controlling methane-conversion efficiency.