The influence of process parameters on photocatalytic hydrogen production

High-efficiency photocatalysts that are synthesized for hydrogen production via photocatalytic water splitting and glycerol conversion without the generation of additional pollutants are presented. Photocatalytic hydrogen production is particular promising because it utilizes glycerol, which is an inexpensive waste from biodiesel production. The main goal of the investigation was the proper selection of photocatalysts based on finding the optimal conditions of the photocatalytic production of hydrogen in the glycerol-water system. TiO2 as well as TiO2 doped with platinum, palladium or gold (0.1, 0.5, 1 wt%), prepared by the photodeposition and sol-gel method, were applied as photocatalysts. The photocatalysts were characterized by X-ray powder diffraction analysis (XRD). The influences of the preparation methodology, the addition of the doped metal and amount of the doping, radiation intensity, solvent additives, and the amount of photocatalysts on process efficiency were investigated. The efficiency of hydrogen production is high compared to that reported in the literature. It was found that a high yield is impossible without the addition of glycerol or other organic compounds. The hydrogen production exceeded 141 x 10(3) mu mol H-2/h center dot g(cat) when 0.5 wt% Pt doped TiO2 was used. The novelty of this study is the highest hydrogen productivity obtained at a laboratory scale. The production rate of hydrogen depended on the catalyst concentration, the amount of the noble metal in the catalysts and the glycerol concentration. (c) 2018 American Institute of Chemical Engineers Environ Prog, 38: 680-687, 2019