Normal-phase high performance liquid chromatography and characterization of polycyclic aromatic hydrocarbon fraction by matrix-isolation fluorometry

High performance liquid chromatography (HPLC) was employed for normal-phase separation of a complex sample (a shale oil) into fractions containing major classes of compounds. A polar bonded-phase column (Partisil-10 PAC) facilitated the separation. Gradient elution was employed, with n-heptane and dichloromethane comprising the mobile phase. The total elution time was approximately thirty minutes. Room-temperature solution fluorometry, HPLC and gas chromatography were utilized to identify the various fractions of the three-component mixture which was used as a model for the shale oil separation. The polynuclear aromatic hydrocarbon (PAH) fraction of the shale oil was analyzed by matrix-isolation fluorometry. Most of the work used nitrogen matrices. Benzo(b)fluorene, chrysene, p3rrene, benz(a)anthracene and benzo(a)pyrene were identified in the PAH fraction. A quantitative analysis revealed 27 ± 3 ppm BaP in the shale oil sample. These results compared favorably with the results reported by the National Bureau of Standards (NBS).