Oxidation of rapeseed oil, rapeseed methyl ester (RME) and diesel fuel studied with GC/MS.

Small samples (5 mu l) of rapeseed oil, rapeseed oil methyl ester (RME) and a superior quality diesel oil according to the Swedish environmentally class 1 (SEC1) were oxidised at 550 degrees C in a reactor. The compounds produced were analysed using a gas chromatographic (GC) method: direct gas injection with GC/MS. Rapeseed oil and RME produced factor 10 more l-alkenes, dienes, and benzene in comparison with diesel SEC1. Rapeseed oil produced high amounts of acrolein and other aldehydes. Oxidation of RME produced significant amounts of methyl acrylate (2-propenoic acid, methyl ester). The different oils produced a varying number of compounds during the oxidation. The rapeseed oil produced 72 peaks with a peak-area above 100 000-area counts and RME produced 61 peaks, in comparison the SEC1 produced only 27 peaks. (C) 1999 Elsevier Science Ltd. All rights reserved.