DETERMINATION OF AROMATIC-HYDROCARBONS IN GASOLINES BY GAS-CHROMATOGRAPHY FOURIER-TRANSFORM INFRARED-SPECTROSCOPY

The total aromatic contents of gasolines as well as 25 individual gasoline-range aromatic hydrocarbons were quantitated by GC/FT-IR with 1,2-dimethoxyethane as internal standard. Reconstructed selective wavelength chromatograms (SWCs) were used for each analyte to give good selectivities over respective coeluting hydrocarbons. Calibrations and quantitations were based on the peak areas from these SWCs, and all calibration curves were linear. An average relative standard deviation of 0.9% and an average accuracy of 0.9% were found, GC/FT-IR provided analyses comparable to the current EPA-specified GC/MS method with less sample preparation than GC/MS and with the added advantage of the simultaneous measurement of the ethers and alcohols (oxygenates) in the fuels.