Removal of Carbon Monoxide from Hydrogen-rich Fuels over CeO<sub>2</sub>-promoted Pt/Al<sub>2</sub>O<sub>3</sub>

Abstract

A comparative study of catalytic CO oxidation and selective CO oxidation over Pt/Al 2 O 3 and CeO 2 -promoted Pt/Al 2 O 3 catalysts has been investigated for the removal of a trace amount of CO from the reformed gas. The catalysts were prepared by sol gel and incipient wetness impregnation. CO oxidation and selective CO oxidation were carried out with a 5%Pt/Al 2 O 3 and a 5%Pt/15%CeO 2 /Al 2 O 3 . The presence of 15%CeO 2 in the 5%Pt/Al 2 O 3 dramatically improves the activities to CO oxidation and selective CO oxidation at low temperature (<180℃). FTIR results indicate that CO could react with lattice oxygen from ceria and release CO 2 as a product. Low space velocity would obtain high CO conversion at low temperatures while high space velocity would obtain high CO conversion at high temperatures. The results also show that a 5%Pt/15%CeO 2 /Al 2 O 3 can completely oxidize 1% CO at 180℃ with selectivity of 52% and space velocity of 70,000 cm 3 ·g -1 ·h -1 . Under the realistic gas feed with 1%O 2 , this catalyst is very stable and retains its activity and selectivity at 180℃ during 72 h.