Effect of cobalt loading on suppression of carbon formation in carbon dioxide reforming of methane over Co/MgO catalyst

Abstract

Carbon dioxide reforming of methane was studied over Co/MgO catalyst which was prepared by using the direct sol–gel method with different Co loadings. The performance of Co/MgO catalyst was thoroughly investigated over methane (CH4) and carbon dioxide (CO2) conversions, CO and H2 selectivity, syngas ratio (H2:CO) and the rate of carbon deposition. The rate of carbon deposition of Co/MgO catalyst decreased with the lower Co content, which resulted in the formation of small metal crystal size and well distribution. The rate of carbon deposition increased from 0.0016 to 0.2227 gc/gcat h as the Co loadings of Co/MgO catalyst also increased from 10 to 25 mol%. High Co loading formed a weak interaction and larger particles size that promoted the carbon deposition on Co/MgO catalyst during the reaction. The Co/MgO catalyst with 10 mol% of Co loading posed the small particle sizes, which resulted in high CH4 and CO2 conversions of 80 and 86%, respectively, along with the lowest rate of carbon deposition after a 50 h reaction time stream, which was enhanced via strong metal support interaction.