顶空-气相色谱法测定水中苯系物、乙腈和丙烯腈

GC Determination of Benzene Homologues,Acetonitrile and Acrylonitrile in Water with Head-space Sample Introduction

运用顶空-气相色谱法同时测定水中苯系物、乙腈和丙烯腈,使用DB-WAX色谱柱实现了各组分的良好分离。用外标法以峰面积定量,苯系物各组分的质量浓度在0.01～0.10 mg·L^(-1),乙腈的质量浓度在0.20～2.00 mg·L^(-1),丙烯腈的质量浓度在0.10～1.00 mg·L^(-1)范围内呈线性关系。方法的检出限(3S/N)为0.7～19.8μg·L^(-1)。在空白水样的基础上用标准加入法对方法作回收及精密度试验,测得各被测物质的回收率在97.3%～104.8%之间,测定结果的相对标准偏差(n=6)为2.17%～4.24%。

In the simultaneous GC determination of benzene homologues,acetonitrile and acrylonitrile in water samples,the DBWAX capillary chromatographic column was used and satisfactory separation was attained. Five mL of water sample was placed into a sealedhead-space sample bottle,and equilibrated in the automatic headspace sampler at 80℃for 6 rnin.Linear relationships between values of peak area and mass concentration of the analytes were obtained in the ranges of 0.01-0.10 mg·L^-1 for the benzene homologues,0.20-2.00 mg·L^-1 for acetonitrile and 0.10-1.00 mg·L^-1 for acrylonitrile External standard method was adopted in the determination. Detection limits（3S/N） of the method were in the range of 0.7 to 19.8μg·L^-1 separately for the 10 compounds determined.Recovery and precision of the method were tested by standard addition method using a blank water sample as matrix.Values of recovery and RSD＇s（n=6） found were in the ranges of 97.3%-104.8%and 2.17% -4.24%respectively.