水中乙醛和丙烯醛的顶空大口径毛细管气相色谱测定法

Determination of Acetaldehyde and Acraldehyde in Water with Headspace Gas Chromatography

目的建立水中乙醛、丙烯醛的顶空气相色谱(HS-GC)测定方法。方法水中的微量乙醛、丙烯醛经顶空提取后,用DB-624大口径毛细管色谱柱分离,用程序升温方式进行GC分析,以保留时间定性,外标法定量。结果在3.0～250μg/L范围内,乙醛的回归方程为:y=406.83x+0.847,r=0.9999,定性检出限为1.0μg/L,定量检出限为3.0μg/L;在6.2～500μg/L范围内,丙烯醛的回归方程为:y=207.53x-0.450,r=0.9998,定性检出限为3.3μg/L,定量检出限为11.0μg/L。该方法所得的平均回收率为90.0%～95.5%,RSD为2.1%～3.7%。结论该方法操作简便、灵敏度高,适用于水中乙醛、丙烯醛含量的测定。

Objective To establish the method of acetaldehyde and aeraldehyde in water with headspaee gas chromatography. Methods Acetaldehyde and acraldehyde in the water samples were extracted by headspace technology,then analyzed with DB-624 capillary column. In the same time,they 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 In 3.0-250 μg/L, the regression equation for acetaldehyde was y=406.83x＋0.847,r=0.999 9, the lowest detection limit was 1.0μg/L. In 6.2-500μg/L, the regression equation for acraldehyde was y=207.53 x-0.450,r=0.999 8,the lowest detection limit was 3.3μg/L. The rates of recovery were 90.0%-95.5%,and RSDs were 2.1%-3.7%. Conclusion This method is simple,rapid,sensitive and is applicable to the determination of acetaldehyde and acraldehyde in water.