Development of detailed surface reaction mechanism of CO oxidation on Pd for three way catalyst

抄録

In this study, based on the CO conversion rate obtained with a monolith honeycomb catalyst and adsorbed surface species identified with in-situ FTIR for powdered catalyst, detailed CO oxidation surface reaction mechanisms on Pd/Al₂O₃ have been developed. As a result, it is found that CO absorbs onto Pd by linear and bridge regime, which is not detected for Pt and Rh in previous work. Based on those results, thermodynamically consistent detailed surface reaction mechanism for CO/O₂ reaction on Pd is developed. Further, combining the CO / O₂ surface reaction mechanism for Pd with previously developed mechanisms for Pt and Rh, CO conversion rate on bimetal catalysts of Pt/Rh, and furthermore, tri-metal catalyst of Pt/Pd/Rh are simulated and compared with experimental results for several PGM ratios. Results of numerical simulation for various Pt/Pd/Rh ratios as well as CO/O₂ ratios quantitatively agreed with experimental results.