Sensitivity and Identification Indexes for Fuel Oils and Crude Oils Based on the Hydrocarbon Components and Diagnostic Ratios Using Principal Component Analysis (PCA) Biplots

Abstract

In total, 164 oil samples, including 56 crude oils (OILs), 12 light fuel oils (LFOs), 66 heavy fuel oils (HFOs), 12 weathered fuel oils (WHFOs), and 18 weathered crude oil (WOILs) samples, were used to screen the sensitivity and identification indexes using principal component analysis (PCA) biplots. Also, 31 oil samples, including 1 LFO, 15 HFOs and 15 OILs, were used for validation by PCA biplots. The sensitivity indexes were determined from PCA biplots based on 143 components; light n-alkanes exhibited good positive correlation with LFOs, aromatic hydrocarbons displayed positive correlations with HFOs, and terpanes and steranes were indicative of OIL characteristics. Among 43 diagnostic ratios, the sensitive diagnostic ratios were screened for LFOs, HFOs, and OILs, using PCA biplots. Thirty-eight (38) diagnostic ratios that could discriminate three types of oils were chosen: 21 diagnostic ratios were chosen for the classification of OILs and HFOs, 19 diagnostic ratios could identify OILs and fuel oils (FOs) (including LFOs and HFOs), and 6 diagnostic ratios could discriminate between LFOs and the other two types of oils (OILs and HFOs). In addition, all of the ratios could resist weathering, which means that all of the results included weathered oil samples. All of the identification indexes, including 143 hydrocarbon components, and 43, 38, 21, 19, and 6 diagnostic ratios, were validated by PCA biplots based on 31 oil samples.