Studies of methods for hydrocarbon type analysis of gasolines

Abstract

The hydrocarbon type analysis of gasolines by high-performance liquid chromatography (HPLC) using fluorocarbon eluents has been investigated. These mobile phases have a very low refractive index and were used to minimise the variations in the response of the detector with compositional changes in the samples. Fluorocarbons are very expensive solvents and microbore HPLC columns have been used to reduce the cost of the analysis. The conditions for the successful separation of gasoline into saturates, aromatics and olefins have been optimised and are described. The retention times of pure hydrocarbon standards have been determined using these conditions. The calibration of the detector and the use of this calibration for the analysis of gasoline samples is described. It has been demonstrated that the hydrocarbon type analysis of gasolines is not possible by HPLC with the detectors currently available.