Measurement and modeling of adsorption/desorption phenomena on traps for low temperature exhaust emissions control
Josh Pihl, Oak Ridge National Laboratory
As combustion engine efficiency improves, exhaust temperatures will continue to decrease. In response to the difficulties of low temperature emissions control, the U.S.DRIVE government/industry partnership has issued a challenge to develop catalytic materials that can convert 90% of emissions at 150 C. While numerous efforts are underway to develop catalysts that light-off at temperatures below 150 C, trap materials, such as passive NOx adsorbers and hydrocarbon traps, could play a critical role in enabling high efficiency advanced combustion engines to meet emissions regulations. Since they are designed to trap criteria pollutants at low temperatures and release them at higher temperatures when conversion catalysts have lit off, modeling the performance of trap materials requires accurately capturing both storage and release processes. This presentation will discuss work aimed at accurately measuring and modeling the fundamental adsorption and desorption phenomena occurring on commercially relevant low temperature trap materials.