固相萃取-气相色谱法测定水中四乙基铅含量

GC Determination of Tetraethyl Lead in Water with Solid Phase Extraction

水样经Supelco C18固相萃取柱富集样品中四乙基铅,用正己烷淋洗,洗脱液于40℃水浴氮吹浓缩至0.5mL,供气相色谱仪测定。用HP-5色谱柱分离,用电子捕获检测器测定。四乙基铅的峰面积与其质量浓度在0.05～5.0μg.L-1范围内呈线性,方法检出限(3S/N)为0.02μg.L-1。在3种不同浓度水平条件下对方法的回收率和精密度进行了试验,测得回收率在89.0%～92.4%之间,测定值的相对标准偏差(n=7)在3.5%～5.0%之间。

Tetraethyl lead in water sample was enriched by passing through Supelco C18 SPE column, and was eluted from the column with n-hexane, and concentrated to 0. 5 mL by Ne-blowing in a water bath at 40 ℃, which was used for GC determination. HP-5 chromatographic column was used for separation and ECD was used in the determination. Linear relationship between values of peak area and mass concentration of tetraethyl lead was obtained in the range of 0. 05--5.0, with detection limit （3S/N） of 0. 02μg·L^-1 of the method were tested at 3 concentration levels, giving results of recovery in the range RSD＇s （n=7） in the range of 3.5%-5.0%. Recovery and precision of 89.0%0--92.4%, and RSD＇s （n=7） in the range of 3.50/oo--5.0%.