Composition And Catalytic Activity Of Cu-Ce-O Catalysts

In order to resolve the environmental pollution problem caused by CO and HC, Cu-Ce-O catalysts are studied in this paper. The specific methods are as follows:1. Five kinds of Cu-Ce-O catalysts with different n(Cu)/n(Ce) are prepared.Catalytic activities for CO oxidation are measured over these catalysts as well as over pure CuO and CeO2 as catalysts, results show that their catalytic activities are higher than that of pure CuO and CeO2. XRD spectra show that no characteristic peak of CuO can be found on the spectrum of the highest activity Cu0.15Ce0.85Ox catalyst, only the characteristic peaks of fluorite type structure of CeO2 can be found. This means high activity of the catalyst is caused by the synergism effect of highly dispersed CuO over CeO2. Kinetic parameters study of this system show that it fits the rule of Constable plot very well, this means all of these five catalysts have similar properties. In order to study the effects of adsorption amounts of oxygen, carbon monoxide and carbon dioxide, and the reducibility of oxygen containing species to catalytic activities of these catalysts, H2-TPR, O2-TPD, CO -TPD and CO2-TPD studies are carried out too.2. The effect of calcination temperature on the activity of Cu0.15Ce0.85Ox catalyst is also studied in great detail, results show that 600Co is the best calcination temperature. Characteristic results of H2-TPR and O2-TPD over Cu0.15Ce0.85Ox catalyst of different calcination temperature show that calcined at 600, Cu0.15Ce0.85Ox has the lowest reduction temperature, the lowest O2 desorption temperature and the largest O2 absorption amount .3. Cu0.15Ce0.85Oxis supported on different supporters and their catalytic activities for CO oxidation are measured. It is observed that supported on mullite, Cu0.15Ce0.85Ox has the optimal catalytic activity. Moreover, H2-TPRand O2-TPD studies also proved it. At last, the relative kinetic is studied particularly.