Mitsubishi Status Report on Low Emission Concept Vehicles

During the past four years, Mitsubishi Motors Corporation has been active in the design and development of catalytic converter systems in the IIEC Program.

Experience indicates that an effective dual catalytic converter, consisting of a NO_x catalyst and a HC/CO catalyst, is indispensable to achieve the stringent IIEC targets, established on the basis of 1976 Federal Standards. However, there still remains a major difficulty of meeting the NO_x target since NO is regenerated in the HC/CO catalyst in the dual converter system.

This paper describes our major efforts in seeking a breakthrough to control the NO_x emission, and covers some noteworthy findings on transient NO concentrations at the inlet and outlet of HC/CO converter in an experimental dual converter.