The development of a zeolite-based (HC Trap type) cold-start catalyst（CSC） for the future more stringent vehicle tailpipe emission standards, part III

This is a follow-up report (part III) of the two precedents [1&2] about the development of a zeolite-based (HC Trap type) cold-start catalyst（CSC）for the future more stringent vehicle tailpipe emission standards. The vehicle tests under the low temperature (-7℃) were performed. The CSC was able to decrease significantly amount of cold-start NMHC under -7℃ more than in the standard room temperature WLTC test and clarify the concerns of the potential interference caused by extra condensed water at low temperature in reducing cold-start NMHC of this type of catalyst. The CSC was aged for 240 hours at 800℃ which is above the maximum temperature (760℃) in the after treatment system during the standard road cycle (SRC) test of a targeted HEV vehicle. It was capable to retain significant amount of capability in decreasing cold-start NMHC although not as effective as aged under 750℃ reported in our precedent reports, and it is concluded that this CSC can be applied to different locations in this vehicle's aftertreatment system except the first close-coupled (CC) catalyst location due to the OBD requirements. The CSC was also applied to a Tier3 Bin30 certified HEV vehicle and decreased the vehicle tailpipe emission to below Bin20 engineering target under double UDDS cycle test. The performance of the CSC with different zeolite loadings were also investigated and reported in this manuscript.