The role of the composition of a Na2WO4/Mn/SiO2 catalyst in the oxidative coupling of methane by chemical looping experiments was investigated. The authors have analyzed a series of Na2WO4/Mn/SiO2 catalysts supported on mesoporous silica. It was found that the chemical looping performance of the oxidative methane coupling strongly depends on the exact composition of the catalyst and was highest at 2 wt% Mn and 5 wt% Na2WO4 on mesoporous silica. The thickness of the active layer controls the O2 storage capacity of the catalysts, which was determined by repetitive methane pulse experiments.
Combined ESR, XRD and XPS experiments were used to show that the oxygen storage capacity is further correlated with manganese loading, which is in line with the reversible change of Mn(III) concentration observed in oxidation and reduction cycles of the material.
Investigation of the role of the Na2WO4/Mn/SiO2 catalyst composition in the oxidative coupling of methane by chemical looping experiments
Vinzenz Fleischer, Ulla Simon, Samir Parishana, Maria Gracia Colmenares, Oliver Görke, Aleksander Gurlo, Wiebke Riedel, Lukas Thum, Johannes Schmidt, Thomas Risse, Klaus-Peter Dinse, Reinhard Schomäcker
J. Catal. A, 2018, 360, 102-117 | DOI: 10.1016/j.jcat.2018.01.022