An experimental investigation was conducted to analyze the absorption characteristics of deposited diesel soot by differential thermal analysis, thermal gravimetric analysis. and solid phase micro-extraction gas chromatography analysis The results showed that dry diesel soot contained 2-3%w (percent by weight) of water and a maximum of 5%w hydrocarbons Water wetted soot contained up to 40%w water, while diesel wetted soot contained up to 60%w hydrocarbons. The hydrocarbons extracted from the soot were primarily hydrocarbons higher than C(12)H(26) with little evidence of lighter hydrocarbons. (c) 2009 Elsevier Ltd All rights reserved.