Preparation of Au/ZnO catalyst and its catalytic performance for CO oxidation at ambient temperature and moisture

The catalytic performance of Au/ZnO catalysts prepared by a coprecipitation method for CO oxidation at ambient temperature and moisture was studied. I t was found that the chemical composition, the activity and the stability o f the catalysts were greatly changed with the variation of calcination temp erature. The sample calcined at 240 degreesC showed the best stability, i. e. it can maintain CO complete conversion for 600 h. XRD, FTIR, TEM and UV- Vis results indicated that gold could be highly dispersed on the surface of ZnCO3 or ZnO, with the mean diameter of gold particle being 2-5 nm. The ty pe of support was the main influencing factors on the stability of Au/ZnO c atalysts, the stability of ZnO supported gold catalysts was better than tha t of the ZnCO3 supported gold samples, The smaller of ZnO particle and the bigger of S-BET, the better of the stability of Au/ZnO catalysts was obtain ed.