Lean methane catalytic combustion over the mesoporous MnOx-Ni/MgAl2O4 catalysts: Effects of Mn loading

In the current investigation, the textural features and catalytic efficiency of the Mn-promoted Ni/MgAl2O4 catalysts were evaluated in the catalytic combustion of lean methane. The results demonstrated that adding manganese oxide up to 5 wt.% to the catalyst improved the structural features and light-off temperatures due to the increase of the reduction degree and oxygen vacancies. The role of the Tcalcination and processing factors on the methane conversion of the 5%Mn-20%Ni/MgAl2O4 catalyst was also studied. The results indicated that the CH4 conversion decreased with the increment of O2/CH4 molar ratio and GHSV value. The stability test revealed that the prepared sample exhibited high stability during 10 h time on stream. Furthermore, the obtained results indicated that the BET area, reduction degree, oxygen mobility, and catalytic performance increased with decreasing the calcination temperature from 700 to 500 degrees C. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.