Preparation and evaluation of A/ BaO‐MnO x catalysts (A: Rh, Pt, Pd, Ru) in lean methane catalytic combustion at low temperature

Abstract

Lean methane catalytic combustion was studied over various noble metal catalysts supported on 10 wt% BaO-MnOx (BM), and the results demonstrated that the Rh/BM catalyst could present a dramatic change in the light-off temperature. The influence of the Rh loadings on the physicochemical features and catalytic activity and stability in CH4 combustion was evaluated in detail. The performance of the catalyst was evaluated using the temperatures (T50% and T90%) required for achieving methane conversion of 50% and 90%. The 1 wt% Rh/BM catalyst possessed the best performance with T50% = 279°C and T90% = 350°C and the light-off temperature of the 1wt%Rh/BM catalyst was about 50°C lower than that obtained for the 10wt% BaO-MnOx. The results indicated that the 1 wt% Rh/BM exhibited high stability even in the presence of various concentrations of CO2 and water vapor. Moreover, the influence of processing conditions such as pretreatment atmospheres, GHSV, and feed ratio was examined on the CH4 conversion. The 1 wt% Rh/BM catalyst was also utilized in the CO oxidation process, and the results presented a high activity at low temperature.