Platinum based core–shell catalysts for sour water–gas shift reaction

Abstract

Pt@CeO 2 and Pt@Ce 0.67 Zr 0.33 O 2 prepared by microemulsion method were studied for water–gas shift reaction in pure syngas and sour syngas from 573 K to 773 K. Both showed high catalytic activities in pure syngas with CO conversion (X CO ) nearly to equilibrium status at temperature above 723 K, and the side reaction of methanation was inhibited throughout the temperature range. Pt@Ce 0.67 Zr 0.33 O 2 showed lower X CO in pure syngas, but higher in sour syngas than Pt@CeO 2 , indicating that the former is more resistant to H 2 S than the latter. Although a decrease in X CO was observed in sour syngas relative to pure syngas, stability experiments carried out over Pt@Ce 0.67 Zr 0.33 O 2 indicated that the catalytic activity could be recovered after the removal of H 2 S. ► Platinum based core–shell catalysts were firstly studied for sour WGS. ► Core shell shows high activities in pure syngas but no methanation even at 773 K. ► The catalysts deactivation in sour syngas was partly irreversible. ► The reason is mainly due to the absence of surface platinum.