Cold start emissions at q22, y7 and y208C ambient temperatures from a three-way catalyst TWC/ car: regulated and unregulated exhaust components

A project initiated by the Swedish Environmental Protection Agency SEPA. concerning cold start driving conditions is partially reported in the present paper. A three-way catalyst car was run in accordance with the European driving cycle EDC. at 228C, y78C and y208C ambient temperatures. The diluted exhaust was analyzed for: Carbon monoxide CO., unburned fuel hydrocarbons HC., oxides of nitrogen NOx., particulates, light aromatics, alkenes, green house gases, aldehydes and polycyclic aromatic hydrocarbons PAH. in particles and in the gaseous phase. As expected, the emission factors of both regulated and unregulated exhaust components increased at lower ambient temperatures. However, the emissions did not increase uniformly. The mutagenicrcarcinogenic compound benzwaxpyrene for example, increased more than 100 times while CO and HC only increased 5]20 times at the lowest ambient temperature studied.