The efect of CO2 on catalytic activity for CO oxidation on Cu-Ce-O fluorite-type complex oxides has been investigated. CO2 played an inhibiting role in CO oxidation on the cat-alyst simlar to what happened on CeO2. As CO2 was introduced into the feed, the coliversion of CO to CO2 on the catalyst was reduced a little. At room temperature,the catalyst could easily adsorb CO2 in large amounts from the air to fbrm carbonate on its surtace.as well as from the yields at low reaction temperature As a restit,the catalyst could be poisoned by CO2 tentatively.The catalytic activity could be recovered to its imitial value on being heated at 300 ℃ or highertemperature.Cu-Ce-O catalyst showed high activity with CO conversion over 98% after being pretreated to desorb CO2 previously.
A series of samples in Cu-Cr-O composite oxide system were synthesized by citratecomplexation method. The catalytic activities of samples were evaluated using CO oxidation astest reaction, and structural imperfection was determined by XRD analysis. The results indicatethat two phases coexisting under the preparative conditions result in structural imperfection of thesamples, which leads to enhanced activities of Cu-Cr-O composite oxides. The catalytic activityfor CO oxidation reaction increases with Cu3+ contents in the samples.
