Carbon dioxide photoconversion. The effect of titanium dioxide immobilization conditions and photocatalyst type

Carbon dioxide and water vapor were effectively photoconverted to methane using either pure or modified-TiO2 and UV-Vis irradiation. The process of photoconversion in the gas phase was carried out in a tubular reactor equipped with a perforated TiO2-coated support. The effect of selected parameters of TiO2 immobilization procedure, such as the time and temperature of drying step and the photocatalyst amount, on photocatalytic efficiency was investigated. The effect of TiO2 loading with Ag/Au nanoparticles on CO2 photoconversion efficiency was also studied. CH4 was found to be the major photoreduction product. The highest methane production was observed after irradiation of CO2+H2O mixture over Au-TiO2 photocatalyst. After one hour of UV-Vis irradiation 503 ppm of methane was formed.