SUMMARYThe propionic acid (HPr) is one of the main by-products during fermentative H 2 process. To efficiently convert HPr to H 2 gas, photocatalytic H 2 production from HPr solution with the use of Pt/TiO 2 photocatalyst under ultraviolet light has been studied in this research. The Pt/TiO 2 photocatalyst has been prepared by the sol-gel method and further characterized by X-ray diffraction, TEM and XPS. Effects of Pt loading amount, HPr concentration, initial pH value on photocatalytic H 2 production have been investigated in detail. From practical point of view, the H 2 evolution from HPr solution under UV irradiation for prolonged time has been studied as well. The Langmuir model can be able to describe the relationship between HPr concentration with the maximum rate of H 2 production. The apparent quantum efficiency and apparent energy conversion efficiency are found to 1.65 and 0.72%, respectively. To better understand the photocatalytic H 2 process over Pt/TiO 2 , a possible mechanism for the degradation of HPr has been proposed as well. Based on our results, an efficient route for hydrogen production from renewable biomass can be established by coupling biological H 2 production process with photocatalytic H 2 production process.