Improvement of Preferential Co Oxidation Activity Over Cuo/Co3o4-Ceo2 Catalysts: Effect of Co/Ce Ratio

Abstract

A series of Co 3 O 4 -CeO 2 supports with different Co/Ce ratio have been synthesized by using polyethyleneglycol (PEG) as a surfactant. The catalytic performance tests indicated the activity of the catalysts is better than the corresponding support. In addition, CuO/(0.7)Co 3 O 4 -CeO 2 displayed the best activity with 100% CO conversion and 93% O 2 selectivity at 120 °C. Furthermore, the stability test of CuO/(0.7)Co 3 O 4 -CeO 2 expressed the activity can be retained at 80% for 80h at 100 °C. Catalysts and supports were characterized by BET, XRD, TPR and TPD techniques. Discussion of the results showed that the strongest lattice distortion and the best reducibility of Co 3 O 4 -CeO 2 supports were both negative factors for the catalytic activity. More precisely, an appropriate Co/Ce ratio can restrain the stronger interaction between cobalt oxide and ceria to promote the formation of reducible copper species.