Prevention against catalytic poisoning by H2S utilizing TiO2 photocatalyst

Prevention against H2S-derived catalyst deactivation on Pd catalyst (Pd/TiO2) was investigated using TiO2 photocatalytic reaction. The catalytic activity was evaluated by CO oxidation. In the dark, the catalytic activity reduced and completely deactivated in the presence of H2S. In contrast, under UV light illumination condition, even in the presence of H2S with the same concentration, it was found that the catalyst kept the activity because of the photocatalytic reaction of TiO2, resulting in the oxidation of H,)S to sulfate. The completely deactivated catalyst was also regenerated by the photocatalytic reaction. (c) 2004 Elsevier B.V. All rights reserved.