多维气相色谱法测定车用汽油含氧化合物方法改进研究

一直以来车用汽油中含氧化合物分析基本均采用ASTMD4815或SH/T0663的方法,但随着车用汽油产品标准GB/T17930-2006版的出台,ASTMD4815和SH/T0663两种方法存在着部分含氧化合物分离效果较差、甲醇检测限达不到要求的问题,因此该分析方法迫切需要改进。该文提出采用多维气相色谱,利用经过硅烷化处理后的约1mTCEP微填柱和30mHP-1弹性毛细管柱,TCD和FID双检测器进行样品分离及检测,经过对柱系统和操作条件的优化,可准确地分析车用汽油中C1～C4醇类和醚类含氧化合物,甲醇检测限达到0.05%。方法重复性的相对标准偏差(RSD)≤0.827%,标准样品回收率在90%～110%之间。

Research of Oxygenates of Gasoline by Multi-Dimension Gas Chromatography

By the standard GB/TI7930-2006 about gasoline presented, for the question of bad separation of some oxygenates and the detection limit for methanol not meeting with requiring, methods of ASTMD4815 and SH/T0663 used for detecting oxygenates in gasoline are required to improve. The paper reported an analytical method for separating C 1-C4 oxygenates in gasoline using multi-dimensional GC coupled with two detectors of TCD and FID. After the proper selection of column system and optimization of chromatographic conditions, the method can achieve oxygenates separation with good reproducibility and good precision. The detection limit of methanol is lower than 0.05 %, the relative standard deviations of repeatedly detecting. The oxygenates were all lower than 0.827 %, and the recoveries of standard compounds were 90 %-110 %.