Insights into the Behaviors of the Catalytic Combustion of Propane over Spinel Catalysts

The behaviors of C 3 H 8 catalytic combustion were investigated over spinel AB 2 O 4 (AB 2 O 4 prepared by co-precipitation method) with two transition metal (A and B are both transition metal elements) and single transition metal (A is transition metal element). Results showed that the spinel AFe 2 O 4 (A = Ni, Cu) owned superior catalytic activities than the spinel AAl 2 O 4 (A = Ni, Cu). In combination with XRD, SEM, Raman, XPS and H 2 -TPR, it could be deduced that higher activity was dependent on abundant surface oxygen vacancy and adsorbed oxygen species. The oxygen activation was enhanced by the doping of another transition metal in B sites of AB 2 O 4 . As a result, the catalytic performance was promoted. Among as-prepared catalysts, NiFe 2 O 4 owned more superior activity and hydrothermal stability for C 3 H 8 combustion than noble metal catalyst. It is expected to be applicable in the removal of VOCs. Graphic Abstract Due to the B-site transition metal doping, the surface oxygen activation behavior of the spinel catalyst can be modulated, which makes AFe 2 O 4 have a higher propane catalytic activity than AAl 2 O 4 .