Determination of Benzene and Toluene in Gasoline by Gas-Liquid Chromatography and It’s Application

Abstract

A simple and rapid method for determination of benzene and toluene in gasoline was developed by using gas chromatograph with flame ionization detector and a commercial DB-1 capillary column. The method was used for analyzing gasoline octane 91 and 95 collected from three brands of 46 gasoline service stations. The method separated benzene and toluene in gasoline at retention times of 4.87 and 8.60 min, respectively. The method could detect benzene and toluene at 0.012 and 0.049 % by volume, respectively. The accuracy of method for determining 3.00 and 4.99 % by volume of benzene in gasoline was 99.00 and 106.01 % respectively with the covariance of variation of less than 9 %. The accuracy of method for determining toluene in gasoline at the concentration of 5.95 and 9.92 % by volume was 103.36 and 93.65 % respectively with the covariance of variation of less than 4. The result showed average benzene in gasoline octane 91 and 95 were 1.69 ± 0.49 % and 1.55 ± 0.41 % respectively and toluene concentrations in gasoline octane 91 and 95 were 7.23 ± 2.47 % and 7.01 ± 1.78 % respectively. The concentrations of benzene and toluene in gasoline in the three brands studied were significantly different.