1.1 本试验方法包括用气相色谱法测定异丙苯（枯烯）的纯度。气相色谱系统的校准是通过外标校准技术进行的。 1.2 已发现该试验方法适用于非芳烃、苯、甲苯、乙苯、苯酚、cymenes等杂质的测量， 吨 -丁基苯， n -丁基苯， n -丙苯， 阿尔法 -甲基苯乙烯， 秒 -丁基苯和二异丙基苯，它们是可以在异丙基苯中发现的杂质。后一种杂质可以通过该方法在1mg/kg至500mg/kg的范围内进行分析（参见 表1 ). 定量限平均为3。 8 mg/kg，而基于 表1 . 1.3 在使用该方法确定测试结果是否符合适用规范时，应根据实践中的舍入方法对结果进行舍入 第29页 . 1.4 以国际单位制表示的数值应视为标准。本标准不包括其他计量单位。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 有关具体的危险说明，请参阅第节 9 . 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 此测试方法适用于设定 1.2 以及用作生产异丙苯或在制造过程中使用异丙苯的内部质量控制工具。它也可以用于涉及异丙苯的开发或研究工作。 5.2 该试验方法可用于测定存在正常杂质的异丙苯的纯度。如果异丙苯中存在极高沸点或异常杂质，则该测试方法不一定能检测到这些杂质，并且纯度计算会出错。 5.3 过氧化氢异丙苯（如果存在）将产生热分解产物，主要是AP和DMPC，如 4.1 ，将在色谱图中洗脱，从而给出错误的结果，除非如中所示将其排除在外 4.1 。也有可能得到错误的跟踪结果 阿尔法 -异丙苯中存在的甲基苯乙烯，如果入口被非- 挥发性异物。 5.4 异丙苯生产过程中通常存在的非芳烃，特别是非沸石烃，会干扰二甲苯的测定（如果存在）。

1.1 This test method covers the determination of the purity of isopropylbenzene (cumene) by gas chromatography. Calibration of the gas chromatography system is done by the external standard calibration technique. 1.2 This test method has been found applicable to the measurement of impurities such as nonaromatic hydrocarbons, benzene, toluene, ethylbenzene, phenol, cymenes, t -butylbenzene, n -butylbenzene, n -propylbenzene, alpha -methylstyrene, sec -butylbenzene, and diisopropylbenzenes, which are impurities that can be found in isopropylbenzene. The latter impurities can be analyzed over a range of 1 mg/kg to 500 mg/kg by this method (see Table 1 ). The limit of quantitation averages 3.8 mg/kg while the limit of detection for these impurities averages 1.1 mg/kg based on the data in Table 1 . 1.3 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off in accordance with the rounding-off method of Practice E29 . 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 9 . 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 This test method is suitable for setting specifications on the materials referenced in 1.2 and for use as an internal quality control tool where isopropylbenzene is produced or is used in a manufacturing process. It may also be used in development or research work involving isopropylbenzene. 5.2 This test method is useful in determining the purity of isopropylbenzene with normal impurities present. If extremely high boiling or unusual impurities are present in the isopropylbenzene, this test method would not necessarily detect them and the purity calculation would be erroneous. 5.3 Cumene hydroperoxide, if present, will yield thermal decomposition products, primarily AP and DMPC as stated in 4.1 , that will elute in the chromatogram thereby giving incorrect results unless they are excluded as indicated in 4.1 . It is also possible to get erroneous results for trace alpha -methylstyrene present in isopropylbenzene if the inlet has become unduly contaminated with non-volatile foreign substances. 5.4 The nonaromatic hydrocarbons commonly present from the isopropylbenzene manufacturing process, particularly a non-zeolitic one, will interfere with the determination of xylenes (if present).