Comparative Study on Nano-Sized 1 wt% Pt/Ce_(0.8)Zr_(0.2)O2and 1 wt% Pt/Ce_(0.2)Zr_(0.8)O2 Catalysts for a Single Stage Water GasShift Reaction

摘要

A comparative study on nano-sized Pt/Ce_(0.8) Zr_(0.2)O2 and Pt/Ce_(0.2)Zr_(0.8)O2 catalysts in a single stage water gas shift (WGS) reaction was carried out. These catalysts were prepared by impregnating 1 wt% Pt on nano-sized cubic (Ce_(0.8)Zr_(0.2)O2) and tetragonal (Ce_(0.2)Zr_(0.8)O2) supports. Both catalysts have been applied to WGS under identical conditions to understand beneficial effect of cubic/tetragonal phases of Ce_((1-x))Zr_((x))O2. 1 wt% Pt/Ce_(0.8)Zr_(0.2)O2 exhibited higher CO conversion than 1 wt% Pt/Ce_(0.2)Zr_(0.8)O2. In addition, 1 wt% Pt/Ce_(0.2)Zr_(0.8)O2 catalyst showed relatively stable activity with time on stream. The high activity/stability of 1 wt% Pt/Ce_(0.2)Zr_(0.8)O2 catalyst was correlated to its higher Pt dispersion and easier reducibility.