Photocatalytic Reduction of CO2 to CH4 and Its Reaction Kinetics in Concentrating Solar Light Reactor
Institute of Chemical Reaction Engineering, Department of Industry Catalysis, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou310014, China
Abstract：To investigate the effect of light intensity on the reaction kinetics of photocatalytic reduction of CO2 to methane, the light intensity was changed by means of concentrating. Under the condition of variable light intensity, the behavior of TiO2, ZnO, SnO2, Fe2O3 and WO3 catalysts prepared by anodic oxidation method to reduce CO2 to methane were investigated, and the catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet-visible absorption spectroscopy (UV-Vis). It is found that the increase of light intensity due to concentrating can effectively improve the catalytic performance of the catalyst and the rate of methane formation. At the geometric concentration ratio of 12.9, the maximum methane production rate reached 19.15, 10.62, 34.56, 30.99 and 23.76 μmol/(g-cat?h), respectively. On this basis, the mechanism of photocatalytic reduction of CO2 to methane was discussed. The change of reaction order of light intensity was introduced, and the modified kinetic equation was obtained. The reason why the ratio of the photoelectron pairs generation to recombination constant changes with the light intensity explained the change in the intensity reaction order of intensity.
Fang Xiaoxiang,Li Dong,Liu Huayan et al. Photocatalytic Reduction of CO2 to CH4 and Its Reaction Kinetics in Concentrating Solar Light Reactor[J]. 化学反应工程与工艺, 2018, 34(2): 151-159.
