顶空大口径毛细管气相色谱法测定饮用水中二氯甲烷和二氯乙烯的研究

Determination of dichloromethane and dichloroethylene in drinking water with headspace gas chromatography

目的：探讨生活饮用水中二氯甲烷、1,1二氯乙烯和1,2二氯乙烯的顶空气相色谱（HS-GC）测定方法。方法：水中的微量二氯甲烷和二氯乙烯经顶空提取后,应用DB-624大口径毛细管色谱柱,采用程序升温方式进行GC分析,以保留时间定性,外标法定量。结果：二氯甲烷、1,1二氯乙烯、反式1,2二氯乙烯、顺式1,2二氯乙烯的线性范围分别为0.85～167.5、0.07～12.1、0.40～77.8、0.53～118.8μg/L范围,最低检出浓度分别为0.25、0.02、0.12、0.16μg/L,水样加标回收率为97.3%～114.6%,RSD为5.6%～11.1%。结论：方法仅用4.2m in完成饮用水中二氯甲烷和二氯乙烯的分离和测定,操作简便、灵敏。

Objective：To establish a method for determination of dichloromethane,1,1-dichloroethylene and 1,2——dichloroethylene in drinking water with headspace gas chromatography.Methods：Dichloromethane and dichloroethylene in the water were extracted by headspace technology,then analyzed with DB-624 capillary column.Meanwhile,dichloromethane and dichloroethylene were determined with GC by controlling the temperature.Retention time of the peaks was used for qualitative analysis,while external standard method was used for quantitative analysis.Results：Dichloromethane,1,1-dichloroethylene,1,2-dichloroethylenetrans,1,2-dichloroethylene were 0.85~167.5,0.07~12.1,0.40~77.8,0.53~118.8 μg/L in linear range.The lowest determination limit was 0.25,0.02,0.12,0.16 μg/L,the rate of recovery 97.3%～114.6%,and RSD 5.6%～11.1%.Conclusion：This method can separate efficiently and determine dichloromethane and dichloroethylene accurately in the water and only takes 4.2 minutes.