【国外标准】 Standard Test Method for Determination of Benzene and Total Aromatics in Denatured Fuel Ethanol by Gas Chromatography (Withdrawn 2022)

5.1 Regulations in some jurisdictions, such as California, limit the concentration of benzene and total aromatic content of denatured fuel ethanol in order to reduce the ozone reactivity and toxicity of automotive evaporative and exhaust emissions. Results from this test method may be used to assess product quality and to meet new fuel regulations.1.1 This test method covers the determination of benzene and total aromatics in finished denatured fuel ethanol by gas chromatography.1.2 Total aromatics are determined by adding the concentrations of benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, and C9 and heavier aromatics.1.3 The aromatic hydrocarbons are separated without interferences from other hydrocarbons in denatured fuel ethanol. Nonaromatic hydrocarbons having boiling point greater than that of n-dodecane can cause interferences with the determination of the C9 and heavier aromatics. For the C8 aromatics, p-xylene and m-xylene co-elute while ethylbenzene and o-xylene are separated. The C9 and heavier aromatics are determined as a single group.1.4 This test method covers the following concentration ranges: benzene, 0.01 % to 0.08 % by mass and total aromatics, 0.29 % to 2.67 % by mass.1.5 Results are reported to the nearest 0.01 % by mass or liquid volume.1.6 The values stated in SI units are to be regarded as standard.1.6.1 Exception—The values given in parentheses are provided for information only; they may not be exact equivalents.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.