Aldehydes and Ketones in Engine Exhaust Emissions—a Review

Abstract
Aldehydes and ketones in engine exhaust gases are receiving increased attention and are beginning to be subject to special legislation due to their carcinogenic and ozone formation potential. This paper gives an overview of their properties as well as of the basic chemistry and conditions of their formation in internal combustion engines. Extensive research on the effects of engine operation and fuelling parameters is reviewed with specific references to gasoline, diesel, natural gas and methanol fuelled engines. This is accompanied by the review of the studies of the performance of exhaust catalytic converters with respect to aldehydes. Aldehyde detection and measurement methods are summarized and analysed from the point of view of their applicability to exhaust gas analysis.