Comparative study of CuO supported on CeO_2, Ce_(0.8)Zr_(0.2)O_2 and Ce_(0.3)Al_(0.2)O_2 based catalysts in the CO-PROX reaction

摘要

CuO supported on CeO_2, Ce_(0.8)Zr_(0.2)O_2 and Ce_(0.8)Al_(0.2)O_2 based catalysts (6%wt Cu) were synthesized and tested in the preferential oxidation of CO in a H_2-rich stream (CO-PROX). Nanocrystalline supports, CeO_2 and solid solutions of modified CeO_2 with zirconium and aluminum were prepared by a freeze-drying method. CuO was supported by incipient wetness impregnation and calcination at 400 ℃. All catalysts exhibit high activity in the CO-PROX reaction and selectivity to CO_2 at low reaction temperature, being the catalyst supported on CeO_2 the more active and stable. The influence of the presence of CO_2 and H_2O was also studied.