A MULTIVARIATE STATISTICAL-ANALYSIS OF CHEMICAL-COMPOSITION AND PHYSICAL CHARACTERISTICS OF 10 DIESEL FUELS

Ten different diesel fuels were tested for 26 physical and 45 chemical parameters. Principal components analysis (PCA) was used for statisti cal analysis of the physical and chemical data separately and combined . Physically, these and similar fuels may be described in a few genera l terms, such as viscosity, boiling residue, cetane number and density . With three PCs, 88% of the variation in physical terms was accounted for. Only one fuel remained poorly described by the model. The most d escriptive chemical components include 1-methylphenanthrene as represe ntative of a major fraction of the polycyclic aromatic hydrocarbons (P AH). With three PCs, all fuels were well accounted for, with 80% of th e variation in chemical parameters explained. Although PCA does not pr ovide a means of deriving causal relations, it may be used to find pat terns of intercorrelated variables. With both chemical and physical pa rameters included in a final PCA, relations between chemical contents and physical characteristics were observed for e.g. PAH/olefins/naphth enes and viscosity.