Distinguishing crude oils from heavy fuel oils by polycyclic aromatic hydrocarbon
fingerprints
Xing Liu, Zhen Wang, Xindong Ma, Hengzhen Xu and Ziwei Yao
National Marine Environmental Monitoring Center, Dalian, PR China.
E-mail:
zwyao@nmemc.org.cn
PAH biomarkers are important factors in the identification of the source of spilled oil because of
the specificity and high resistance to biodegradation of such biomarkers. A novel method for
distinguishing heavy fuel oils from crude oils is proposed in this study. This method comprises gas
chromatography mass spectrometry analysis and principal component analysis (PCA) of the
diagnostic ratios of selected polycyclic aromatic hydrocarbons (PAHs). The method was applied to
15 heavy fuel oils (B1 to B15) and 32 crude oils (C1 to C32) for distinction. Oil samples were
collected from Turkmenistan, Korea, China, Vietnam, Morocco, Algeria, Sultan, Yemen, Saudi
Arabia, Argentina, Russia, Indonesia, Brazil, Equatorial Guinea, Angola, and Mauritania. The
discriminative power of PCA was enhanced through the selection of typical PAH diagnostic ratios,
which could be used to distinguish petrogenic from pyrogenic PAHs. The heavy fuel oils have
higher An/P, BaA/C, 2-m-An/total of MP, and PI, as well as lower ΣN/ΣC, ΣP/ΣC, ΣD/ΣC, and
ΣF/ΣC as compared with crude oils. PCA based on 10 PAH diagnostic ratios is a more efficient
method in distinguishing heavy fuel oils and crude oils compared with the plotting of An/P and PI
ratios. The method was confirmed to be highly efficient for distinguishing heavy fuel oils from
crude oils, with a rapid and objective procedure under comprehensive considerations. The method
provides a useful tool to apportion the spilled oil in the marine environment.