Zirconia modified monolithic macroporous Pt/CeO2/Al2O3 catalyst used for water-gas shift reaction

Monolithic macroporous Pt/CeO2/Al2O3 and zirconia modified Pt/CeO2/Al2O3 catalysts were prepared by using concentrated emulsions synthesis route. The catalytic performances over the platinum-based catalysts were investigated by water-gas shift (WGS) reaction in a wide temperature range (180–300 °C). The samples were characterized with thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and temperature programmed reduction (TPR) techniques as well. The SEM and HRTEM results indicated that the monoliths possessed macroporosity, in size of 5–50 μm, and platinum particles were homogeneously dispersed on macroporous materials. XRD and TPR results showed that the interaction between ceria and zirconia oxide was formed and the addition of zirconia could promote the reducibility of platinum oxide on the interface of ceria and zirconia particles, which led to an improvement of catalytic activity in WGS reaction. The results indicated that zirconia modified monolithic macroporous Pt/CeO2/Al2O3 could be fabricated in small size (from millimeter lever to centimeter) and had good reaction activity, which was a potential new route for miniaturization of the WGS reactor.