自配标准代替外购标准优化1,2-二氯乙烷中杂质测定方法

Optimization of the Determination Method of Impurities in 1,2-Dichloroethane with Self-provisioning Standard Instead of Outsourcing Standard

采用气相色谱外标法测定1,2-二氯乙烷中杂质的含量,其杂质组分主要以气液固3种形式存在,前期曲线制作采用以1,2-二氯乙烷为溶剂配制的外购标准进行曲线拟合,但线性系数均达不到0.999以上,发现外购标准基体中因为有本底导致各组分准确度偏低。为了提高方法准确性,消除溶剂本底的存在,采购各组分纯试剂进行自配标准代替外购。根据组分间性质不同,避免相互间作用及出峰时间重合,通过实验选择各组分合适的溶剂进行标准配制,结果各组分线性系数均为0.9999以上,经过不同人员间曲线验证,准确度和精密度均满足要求。

The gas chromatography external standard method is used to determine the content of impurities in 1,2-dichloroethane,the impurity components mainly exist in three forms:gas,liquid and solid.The preliminary curve preparation adopts outsourcing standards for curve fitting,which prepared with 1,2-dichloroethane as solvent.However,the linear coefficients were not above 0.999,it was found that there was a background in the purchased standard matrix,which caused the accuracy of each component to be low.To improve the accuracy of the method and eliminate the existence of solvent background,we purchase the pure reagents of each component,and carry out self-provisioning standards instead of outsourcing standards.According to the different properties of the components and avoid the overlapping of interactions and peak times,we select appropriate solvents for each component through experiments for standard preparation.The results shown that the linear coefficients of each component were all above 0.9999,and the accuracy and precision met the requirements after the curve verif ication between different personnel.