Controlled Distribution of PGM in Transversal and Vertical Direction of Washcoat; New Approach for Targeting Emission at Cold Start and High Speed Region

We have developed a new technology with which we are able to control PGM distribution two-dimensionally along transversal and vertical direction. Vehicle evaluation using naturally aspirated engine suggested that the newly developed catalyst with two-dimensionally controlled Pd distribution shows an improvement of 8% for NMHC and 15% for NOx emissions compared to conventional zone coated catalyst. In addition, the Pd distribution in front zone was further optimized based on the results of light-off tests. Catalyst with three zones shows clear improvement in purification of NMHC at cold start. The higher purification of newly developed catalysts could be attributed to controlled distribution of PGM along transversal and vertical direction which results in deposition of higher amount of PGM at higher temperature region of the catalyst and efficient interactions of exhaust gases and PGM sites.