Application of Photocatalyst to 2-Propanol Dehydrogenation Process in Thermally Regenerative Fuel Cell Utilizing Solar Heat

摘要

Solar thermal cell converts low temperature solar thermal energy into electric power. It consists of chemical reactions of 2-propanol dehydrogenation and acetone hydrogenation, and a fuel cell. In this study, we studied photocatalytic 2-propanol dehydrogenation in order to apply directly sunlight to the solar thermal cell. Noble mater (Pt, Ru, Rh and Pd) supported on TiO_2 was used as a catalyt and we compared carbon-supported noble metal catalyst. A metal loading ratio was 5 wt%. Three kinds of TiO_2 (Ishihara Sangyo Kaisha. LTD:ST-01, ST-21 and ST-31) were used in this study. We examined the activity of various combinations of noble metal and TiO_2 for the reaction under boiling condition and below boiling point with using high pressure mercury lamp, and we evaluated the reaction mechanism. Platinum catalyst supported on ST-01 has the highesst activity. Photocatalytic 2-propanol dehydrogenation with using noble metal supported on TiO_2 is characterized by small retardation by acetone and large hydrogen evolution rate below boiling pont. It is suggested that once acetone and molecular hydrogen are formed on the catalyst surface, they don't remain on the surface and they are easily desorbed from the catalyst.