Effects analysis on hydrocarbon removal performance of an adsorptive catalytic gasoline particulate filter in the gasoline engine during cold start

Abstract

In order to remove hydrocarbon (HC) emission of the gasoline engine during cold start to meet increasingly stringent emission standards, the HC removal performance of a novel adsorptive catalytic gasoline particulate filter (A-CGPF) coated with new composite catalysts is investigated. Then, effects of different factors on HC removal (HC adsorption and conversion) of the A-CGPF during cold start are analyzed. The results show that during first 40 s of the cold start, the cumulative emission of hydrocarbon is greatly reduced. Ambient temperature has a great influence on hydrocarbon removal in the early stage of cold start, and its variation has little effect on MMC. The order of hydrocarbon removal performance during cold start under non-adiabatic condition is MRP > MMC > MP > MC > MPCZ, and the difference of hydrocarbon removal rate between MMC and MRP is only 5%–9%. In addition, the larger ratio of oxidizing components and reductive components λ can lead to the faster temperature rise and the greater hydrocarbon removal rate. The λ value has little influence on the early stage of cold start, but gradually increases the influence on the late stage of that until it is up to 0.95. During soot capture, the ash accumulation has a more significant effect on HC abatement at the late stage of cold start, which can delay the temperature rise in the filter and slightly decrease the hydrocarbon removal rate. This work provides reference for enhancing simultaneous hydrocarbon and soot reduction performance of the A-CGPF under the low temperature and design of coupled after-treatment system.