Abstract: A comparison between high performance liquid chromatography coupling with refractive index detector (HPLC-RID) method and gas chromatography coupling with mass spectrometry (GC-MS) method in terms of determination of aromatics content in diesel, standard recovery rate and blending accuracy were conducted. Eight automobile diesel fuels (VI) samples were tested by the two methods. The results indicated that the blending accuracies of two methods are reliable. The standard recovery rate produces a deviation using HLPC method due to the large amount of components with different structure in real diesel fuels from the model compounds and the difference of response characteristics of the refractive index detector. Somewhat deviations also exist in the content of polycyclic aromatic hydrocarbons and total aromatic hydrocarbons obtained by HPLC.

Key words: aromatic hydrocarbon in diesel, pilycyclic aromatics, HPLC, GC-MS