Effects of pressure on CO2 reforming of CH4 over carbonaceous catalyst

CO2 reforming of CH4 was studied over laboratory-prepared carbonaceous catalysts at atmospheric pressure (0.1 MPa) and high pressure (3.6 MPa). The catalysts were characterized by BET and FITR techniques. The catalytic activity and stability of catalysts were closely related to the reaction pressure. It was observed that the use of higher pressure substantially decreased CO2 and CH4 conversion and increased catalyst deactivation during CO2 reforming of CH4, compared to runs at 0.5 MPa for carbonaceous catalysts. Deactivation was related to carbon formation. Some process adjustment methods, such as increasing the reaction temperature, prolonging reaction residence time, and increasing CO2 and CH4 molar ratio, which could improve catalysts activity and stability. Besides, the positive effect of surface oxygen containing groups (C–O) on catalyst activity had been demonstrated over carbonaceous catalysts. The basic function of the carbonaceous materials surface area also seemed to increase H-abstraction of methane and CO2 adsorption.

► Effects of pressure on CO2 reforming of CH4 was studied.
► The higher pressure decreased CO2 and CH4 conversion.
► Some process adjustment methods could improve catalysts activity and stability.
► oxygen containing group is attributed to H-abstraction of methane and CO2 adsorption.