气相色谱法测定汽油中的甲缩醛含量

The Contents of Dimethoxymethane in Gasoline by Gas Chromatography

利用二维气相色谱技术,测定了汽油中的甲缩醛含量。试样通过一个非极性固定相色谱柱,组分按照沸点大小分离,待环戊烷流出后,反吹非极性柱,环戊烷、甲缩醛及轻组分,经一个强极性固定相色谱柱分离,并通过TCD检测器检测。试验采用外标法定量,甲缩醛的质量浓度在1.0 g/L~50.0 g/L范围内标准工作曲线呈良好的线性关系,相关系数为0.9998。试样加标回收率为100.3%~107.5%,试样重复测定的相对标准偏差小于5.0%,甲缩醛的检出限为0.20 g/L。

Two-dimensional gas chromatography was proposed for the determination of dimethoxymethane in gasoline.The sample was separated by a non-polar stationary phase column,and the components were separated according to the boiling point.After flowing out of the cyclopentane,the non-polar column was reverse-blown,Cyclopentane,dimethoxymethane and light components were separated by a strong polar stationary phase column and detected by TCD detector.The external standard method was used for quantification,the standard working curve of dimethoxymethane showed a good linear relationship in the range of 1.0g/L~50.0g/L,and the correlation coefficient was 0.9998.The recovery rate of standard addition was 100.3%~107.5%,and the relative standard deviation of repeated determination of the sample was less than 5.0%,The detection limit of dimethoxymethane was 0.20g/L.