本方法用于气相色谱法测定高纯度乙苯中的痕量杂质。确定的特定杂质包括苯、甲苯、对二甲苯、间二甲苯、邻二甲苯、异丙苯、正丙苯、1,2-二乙苯、1,3-二乙苯和1,4-二乙苯。非芳烃和未识别的C9+芳烃被确定为复合物。苯和甲苯不能用这种方法从非芳烃杂质中分离出来，但如果需要，可以用UOP方法543“气相色谱法测定高纯度芳烃中的痕量非芳烃”单独测定。除对二甲苯外，任何单一成分的检测下限均为2 mg/kg（质量ppm），对二甲苯的检测下限为10 mg/kg。

This method is for determining trace impurities in high purity ethyl benzene by gas chromatography (GC). Specific impurities identified include benzene, toluene, p-xylene, m-xylene, o-xylene, cumene, n-propylbenzene, 1,2-diethylbenzene, 1,3-diethylbenzene, and 1,4-diethylbenzene. Non-aromatics and unidentified C9+ aromatics are determined as composites. Benzene and toluene may not be separated from the non-aromatic impurities by this method but, if required, may be determined individually by UOP Method 543, “Trace Non-Aromatic Hydrocarbons in High-Purity Aromatics by Gas Chromatography.” The lower limit of detection for any single component is 2 mg/kg (massppm) except for p-xylene, which has a lower detection limit of 10 mg/kg.