Kinetic Study of the CO2 Reforming of CH4 to Synthesis Gas Over Carbonaceous Catalyst

Abstract

The CO₂ reforming of CH₄ over carbonaceous catalyst was performed in a plug flow reactor (PFR) at temperatures range from 1223-1323 K, the ratio of CH₄/CO₂ = 1 and residence time 3-30 s under normal pressure. The outlet gas was analyzed by gas chromatogram (GC-960TCD and GC-950TCD), the carbonaceous catalyst was analyzed with element analyzer and specific surface area analyzer. The experimental results show that the conversion of CH₄ and CO₂ increases with the increase of the reaction temperature and residence time, but the conversion of CO₂ was significantly higher than the conversion of CH₄ at the same reaction condition, which indicate that the gasification reaction of the carbonaceous catalyst and carbon dioxide was occurred during the reforming process. At 1323 K and residence time over 20 s, the conversion of CH₄ and CO₂ can be expected over 90 %. The carbonaceous catalyst is a highly promising catalyst for the CO₂ reforming of CH₄ to synthesis gas. The kinetics of the CO₂ reforming of CH₄ on carbonaceous catalyst was described in a rate law, which the experimental data was analyzed in non-linear regression. The apparent activation energy E_a and the pre-exponential factor A were solved. A comparison is made between calculation data and experimental data of the CH₄ conversion, which illustrates the rationality of the kinetic model.