Toward syngas production from simulated biogas dry reforming: Promotional effect of calcium on cobalt-based catalysts performance

The upgrading of simulated biogas with an equal mole ratio of methane and carbon dioxide through dry reforming over calcium promoted on cobalt-based catalysts was investigated in this work. Catalysts with different loading of calcium oxide were synthesized and used to explore that the calcium loading is critical in the performance of catalysts. At low calcium dosages in a range of 0.1-0.2 wt%, the average Co3O4 crystalline size decreased from 8.15 nm to 6.01-7.43 nm, suggesting well-dispersed cobalt on the surface. In addition, the reducibility and basicity of catalysts were also enhanced with a sufficient addition of promoters. The optimal catalyst, 0.2Ca-10Co/Al2O3, exhibited the best performance with roughly 84% and 89% of CH4 and CO2 conversions, respectively. Moreover, the coke formation was suppressed by 78.72%, enabling higher activity and long-lasting stability. The findings offer new opportunities to enhance the dry reforming of simulated biogas performance using earth-abundant catalysts.