Pt/ZrO2 catalyst for a single-stage water-gas shift reaction: Ti addition effect

Ti modified Pt/ZrO2 catalysts were prepared to improve the catalytic activity of Pt/ZrO2 catalyst for a single-stage WGS reaction and the Ti addition effect on ZrO2 was discussed based on its characterization and WGS reaction test. Ti impregnation into ZrO2 increased the surface area of the support and the Pt dispersion. The reducibility of the catalyst was enhanced in the controlled Ti impregnation (∼20 wt.%) over Pt/ZrO2 by the Pt-catalysed reduction of supports, particularly, at the interface between ZrO2 and TiO2. The significant CO2 gas band in the DRIFTS results of Pt/Ti[20]/ZrO2 indicated that the Ti addition made the formate decomposition rate faster than the Pt/ZrO2 catalyst, linked with the enhanced Pt dispersion and reducibility of the catalyst. Consequently, Ti impregnation over the ZrO2 support led to a remarkably enhanced CO conversion and the reaction rate of Pt/Ti[20]/ZrO2 increased by a factor of about 3 from the bare Pt/ZrO2 catalyst.