A study on the emission characteristics of volatile organic compounds from a state-III diesel engine

Volatile organic compounds (VOCs) from a State-III diesel engine are analyzed by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Over 90 kinds of VOCs are detected from the exhaust gas of a State-III diesel engine under different speeds and loads. The test results indicate that aromatic hydrocarbons, including benzene, toluene, p-xylene, m-xylene, o-xylene, ethylbenzene, styrene, naphthalene etc. have higher emissions, among which the highest is toluene. Under the same speed with the increase of engine load, the styrene emission reduces while the emissions of other aromatic hydrocarbons show a trend of fall first and then rise. The emissions of most aromatic hydrocarbons fall with the rise of engine speed at low-medium load range and have only negligible changes with different engine speeds at high load.