Analysis of polynuclear aromatic hydrocarbons in heavy products derived from coal and petroleum by high performance liquid chromatography

A systematic study was made on the identification and quantitative determination of polynuclear aromatic hydrocarbons (PAHs) in heavy products derived from coal and petroleum with high performance liquid chromatography (HPLC). After the separation of PAHs by a high-resolution column, identification was made through four methods: (1) the relative retention time (RRT) method, (2) the stop-flow-UV scanning method, (3) the method of fluorescence characteristic index Φ′ and (4) the method of V′ index at different UV wavelengths. For the quantitative determination of the components, methods of external standard (E-X), internal standard (I-N) and external standard-response factors (E-F) were compared. The E-F method was recommended by the present paper. For the determination of quantitative response factors (F) two methods were studied, including the HPLC peak-area method (Peak-area method) and the UV absorbance method using a UV spectrometer (absorbance method). The absorbance method was better and is recommended by the present paper. The F values of 30 PAHs from the two different methods are given. The samples analyzed include a coal tar pitch, a thermal cracking residue oil and a residual oil from ethylene production.