Mixed reforming of methane over Ni-K/CeO2-Al2O3: Study of catalyst performance and reaction kinetics

Syngas can be effectively produced by mixed reforming of methane (MRM). In this work, the performance of Ni-K/CeO2-Al2O3 catalyst in this process was investigated in a fixed-bed reactor in the 923-1073 K range. Both potassium and ceria are renowned for improving the performance of Ni catalyst in the reforming process. The influence of reaction conditions (viz. temperature, space time, feed composition and time-on-stream) on the conversion of two reactants CH4 and CO2, yield of the products H-2 and CO and the H-2/CO ratio in syngas were studied. At T = 1073 K and W/Q(0) = 0.17 g-h/L (here, W and Q(0) denote catalyst mass and volumetric flow rate of feed), conversions of CH4 and CO2 were 91.2 and 80.1%. When S/C ratio (or steam-to-carbon ratio) in feed increased from 0.2 to 0.5 mol/mol, H-2/CO ratio at T = 1073 K changed from 1.32 to 2.14 mol/mol. The catalyst performed stably for 50 h of time-on-stream. Reaction kinetics was studied between 973 and 1073 K and power law kinetic model was suggested. The apparent activation energy values for consumption of CH4 and CO2 were found to be 33.3 and 45.5 kJ/mol, respectively. This work is expected to aid catalyst development and reactor design for the MRM process. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The performance of Ni-K/CeO2-Al2O3 catalyst in mixed reforming of methane (MRM) was investigated in this study. Various reaction conditions were studied to analyze the conversion of CH4 and CO2, yield of H2 and CO, and the H2/CO ratio in syngas. The study is expected to assist in catalyst development and reactor design for the MRM process.