Photocatalytic hydrogen production in a solar pilot plant using a Au/TiO2 photo catalyst

The purpose of the present work was to study the efficiency of an Au/TiO2 photocatalyst for the simultaneous hydrogen production and organic pollutant removal from aqueous solutions, under direct solar irradiation, and at pilot-plant scale. Several sacrificial agents (pollutants) like alcohols, organic acids, and the organic content of municipal and industrial wastewaters at acid pH were tested. Also, the effect of salt concentration and ionic strength was checked. The experiments were performed in a Compound Parabolic Collector (CPC) at the Plataforma Solar de Almería (PSA). The Au/TiO2 catalyst showed a remarkable activity towards hydrogen production. Indeed, 6500 μmol H2·L−1 were generated after 5 h, with an accumulated radiation energy of 100 kJ·L−1, and a catalyst concentration of 0.2 g·L−1. The dissolved organic carbon (DOC) concentration showed a positive influence towards the hydrogen production, while the ionic strength showed a clear negative effect. The highest rate of photocatalytic hydrogen production was attained using formic acid as sacrificial agent.