气相色谱法测定乙烯、丙烯中的微量含氧化合物

采用CP-Lowox大口径毛细管色谱柱(10m×0.53mmi.d.)建立了测定乙烯、丙烯产品中多种微量含氧化合物的气相色谱法,并用该方法分析了标样和实际乙烯、丙烯试样,考察了该方法的重复性和准确性。实验结果表明,采用该方法分析乙烯和丙烯产品中可能存在的微量二甲醚、甲基叔丁基醚、甲醇、丙酮、丁酮、乙醇、异丙醇等杂质,分离效果良好,各组分的回收率为94.30%～109.95%,重复测定5次的相对标准偏差小于5.2%,定量结果准确可靠;各物质的检出限为0.5mL/m3,该方法的准确度和精密度良好;该方法可直接气体进样,无须溶液吸收富集,简化了进样预处理过程,可满足乙烯和丙烯产品中含氧化合物的质量监控和实际生产快速分析的需要。

Determination of Trace Oxycompounds in Ethylene and Propylene by Gas Chromatography

A novel gas chromatography method for trace oxycompounds in ethylene and propylene was established using a CP-Lowox capillary column(10 m×0.53 mm i.d.).The trace oxycompounds in ethylene and propylene mainly contain dimethyl ether,methyl tert-butyl ether,methanol,acetone,butanone,ethanol and iso-propanol,which can be separated efficiently by the method.The recoveries of the oxycompounds and the relative standard deviations are in the range of 94.30%-109.95% and less than 5.2%,respectively.The detection limits of the oxycompounds are 0.5 mL/m3.The new method simplifies the sample pretreatment and makes the gas samples be able to be directly injected.