Survey of American (USA) Gasolines (2008)

The regulations for gasoline's content vary depending on the time of year and physical location within the United States while the refinery and distribution system mixes product batches; this results in variability of content. ASTM E1618 requires both the aromatic and alkane EIP patterns of gasoline to compare with references. A survey was conducted by collecting gasoline from Florida to Oregon, from 85 to 93 octane. Samples were analyzed in accordance with ASTM E1618 in various states of evaporation. The range of differences found in the 90% evaporated alkane EIPs is presented and showed a continuum of response when the n-alkane response was compared with the branched alkane response. Similarly, the ratio of the alkane EIP to the aromatic EIP also showed a continuum of response at the 90% evaporated state. Gasoline samples with unusual characteristics are also discussed.