Simplification of the ASTM D3606 Method for the Determination of Benzene and Toluene in Gasoline

Benzene is used as an additive into gasoline to increase octane rating and prevent engine knocking. Being a toxic air pollutant known to have carcinogenic effects, knowledge of its concentration can be of aid in the assessment of possible health hazards to persons handling and using gasoline. The U.S. Federal Clean Air Act and the European Community specifications mandate a level of benzene in gasoline below 1% in volume.1 To meet the specific limits of benzene, an accurate quantitative determination of the compound is essential. The ASTM D3606 method is designed to determine benzene and toluene content in motor and aviation gasoline using packed columns and a thermal conductivity detector (TCD).2 The following methodology describes the determination of these components in gasoline, using the Thermo Scientific TRACE 1310 GC in a split/splitless-backflush configuration using capillary columns and flame ionization detection (FID), for a simpler fully automated analysis. The SSL/backflush injector used in this paper is a user-installable, compact and self-sufficient module featuring all the required hardware components and the electronic carrier gas controls.