(755g) Cu- and Co-Based Catalysts for CO and C3H6 Oxidation in Diesel Exhaust

In recent years, diesel engines have been used to satisfy the transportation and economic demand. However, with low-temperature combustion, some diesel engines emit a large amount of CO and C₃H₆. Therefore, diesel oxidation catalysts (DOCs) have been investigated and applied to oxidize CO and C₃H₆. Typically, DOCs containing Pt and Pd have good performance for oxidizing CO and hydrocarbons, but noble metals are expensive and sensitive to surface poisoning. As a result, less expensive transition metals with abundant amount are another choice. Under mixed feed condition, light-off temperature of both CO and C₃H₆ decreases with the increasing ratio of Co: Cu on bimetallic catalyst Co-Cu/CeO₂. To learn the mechanism of interaction between Cu and Co or with CeO₂, monometallic catalysts of Cu/CeO₂ and Co/CeO₂ are also investigated with the same feeding condition as for bimetallic catalysts. Additionally, single feed gas with CO or C₃H₆ only is also fed to transition metal DOCs to learn whether there is any inhibition on CO oxidation by C₃H₆. DRIFTS and BET are applied to identify intermediates during the catalytic reactions with different temperature and surface area of DOCs, respectively.