MO x and Au/MO x catalysts were prepared by the coprecipitation method and their catalytic performance for CO oxidation was evaluated through the feeding gas with or without water vapor. The results showed that the activity and the stability of MO x catalysts are greatly dependent on the kinds of metal oxides. The activity order of MO x is Co 3O 4>NiO>Fe 2O 3>CuO>MnO x>ZnO>Al 2O 3>Cr 2O 3>CaO>La 2O 3. The water has negative effect on the activity of MO x (M=Co, Cu, Fe, Mn, Ni and Zn) catalysts. The catalytic activity and stability of Au/MO x catalysts are greatly dependent on the properties of MO x. The water has negative effect on the activity of Au/MO x (M=Ca, Cr, Cu,La and Mn) and on the stability of Au/MO x (M=Al, Co, Fe, Mn, Ni and Zn) at ambient temperature.
The catalytic ammoxidation of ethane with oxygen and ammonia was investigated over a series(Sb2O3) promoted ion-exchanged Co-ZSM-5 zeolites(Sb2O3/Co-ZSM-5).The introduction of appropriate amount of Sb2O3 can considerably improve the conversion of ethane,suppress the formation of COx,and increase the total C2 selectivity to acetonitrile and ethylene.Among them,the sample with 5% Sb2O3 loading(in mass fraction) shows a 68.4% ethane conversion at 550 ℃, a 51.6% selectivity to acetonitrile and a 31.7% selectivity to ethylene,and a 35.3% yield of acetonitrile were obtained,which is to our knowledge the highest ever reported for the direct ammoxidation of ethane.