GC_MS法检测车用汽油中的甲缩醛_碳酸二甲酯和N_甲基苯胺.docx

分 析 测 试GC-MS法检测车用汽油中的甲缩醛、碳酸二甲酯和N-甲基苯胺高枝荣，李继文，王川（中国石化 上海石油化工研究院，上海 201208）［摘要］ 采用GC-MS联用法，对车用汽油中含有的非常规添加物甲缩醛、碳酸二甲酯和N-甲基苯胺进行了定性筛查和定量检测。其中，定性分析采用全离子扫描、与标准物质保留时间对照及与标准物质的特征离子图对比等方法；定量分析采用特征 定量离子提取结合内标法。同时考察了汽油本底对这3种化合物定性检测和定量测定的影响。实验结果表明，3种化合物的回 收率在95.83%～101.11%之间，相对标准偏差小于5%，定量数据准确可靠；各组分含量在2%（w）以内，线性响应良好；甲缩 醛和碳酸二甲酯的检测限为0.01%（w），N-甲基苯胺的检测限为0.1%（w）。该方法重复性和再现性均能满足常规分析要求。［关键词］ 车用汽油；气相色谱-质谱联用法；甲缩醛；碳酸二甲酯；N-甲基苯胺［文章编号］ 1000 - 8144（2013）02 - 0230 - 06［中图分类号］ TE 626.21［文献标志码］ ADetermination of Methylal，Dimethyl Carbonate and N-Methyl Aniline inMotor Gasoline by GC-MS MethodGao Zhirong，Li Jiwen，Wang Chuan（SINOPEC Shanghai Research Institute of Petrochemical Technology，Shanghai 201208，China）［Abstract］ The qualitative screening and the quantitative analysis of the three unconventionaladditives for motor gasoline，namely methylal，dimethyl carbonate and N-methyl aniline，wereresearched by gas chromatography-mass spectrometry method. The qualitative analysis was carried out by total ion scanning，contrasting the retention times and the characteristic ion mass spectra of the standard substances. And the quantitative analysis was conducted by a characteristic ion procedure combined with an internal standard method. The effects of the gasoline background on the qualitative analysis and quantitative analysis were investigated. The results showed that the recoveries of the three compounds were in the range of 95.83%-101.11% and the relative standard deviations were less than5%. The detection limits of methylal，dimethyl carbonate and N-methyl aniline were 0.01%(w)，0.01%(w) and 0.1%(w)，respectively. The repeatability of the method can meet the requirement of routine analysis.［Keywords］ motor gasoline；gas chromatography-mass spectrometry method；methylal；dimethyl carbonate；N-methyl aniline常规车用汽油中不含有甲缩醛［1-6］、碳酸二甲酯［7-10］和N-甲基苯胺［11-14］等组分，据研究，这些 物质作为抗爆剂添加到汽油中，可提高汽油的辛烷 值，其功效是常规车用汽油添加物甲基叔丁基醚的 数倍。同时它们的自身成本比常规车用汽油添加物 低很多，因此具有可观的经济利益。将这些非常 规添加物添加到常规车用汽油中后，虽然采用GB17930—2011标准［15］检验仍合格，但这些非常规添加物极易导致汽车发动机等出现