高效液相色谱法同时测定工业氯乙酸中氯乙酸、二氯乙酸和乙酸

Simultaneous Determination of Chloroacetic Acid,Dichloroacetic Acid,Acetic Acid in Industrial Chloroacetic Acid by High Performance Liquid Chromatography

工业氯乙酸样品经体积比为95∶5的0.05%(体积分数)磷酸溶液-甲醇(流动相)溶解后,用0.45μm滤膜过滤,采用高效液相色谱法(HPLC)测定滤液中氯乙酸、二氯乙酸与乙酸的含量。选用Inert Sustain AQ-C18色谱柱为固定相,用流动相进行等度洗脱,在检测波长215nm处进行测定。结果表明:3种目标化合物均达到了基线分离;氯乙酸、二氯乙酸、乙酸的质量浓度与其对应的峰面积在一定范围内呈线性关系,相关系数均大于0.9995;氯乙酸、二氯乙酸和乙酸检出限(3S/N)分别为0.19,0.08,0.12mg·L^(-1)。方法用于实际样品分析,平行测定6次,测定值的相对标准偏差分别为0.11%,6.6%,5.1%,极差分别为0.32%,0.03%,0.03%,满足HG/T 3271-2000对两次测定值差值的规定。对实际样品进行加标回收试验,回收率分别为99.8%~100%,97.5%~101%,96.7%~102%。与标准方法(HG/T 3271-2000)相比,本方法测定值的极差更小。

The sample of industrial chloroacetic acid was dissolved with mobile phase composed of 0.05%phosphoric acid solution and methanol in volume ratio of 95∶5,the mixture was filtered by 0.45μm filter membrane,and the contents of chloroacetic acid,dichloroacetic acid and acetic acid in filtrate were determined by high performance liquid chromatography(HPLC).The Inert Sustain AQ-C18 chromatographic column was chosen as stationary phase,the mobile phase was used for isocratic elution,and the detection wavelength of 215 nm was adopted for determination.The results showed that the 3 target compounds were all got baseline separation.Linearity relationships between mass concentration of chloroacetic acid,dichloroacetic acid,acetic acid and their respective peak areas were all kept in defite ranges,with correlation coefficient greater than 0.9995,and detection limits(3 S/N)of chloroaectic acid,dichloroacetic acid and acetic acid were 0.19,0.08,0.12 mg·L^(-1),respectively.The 6 parallel tests were made on actual samples by the above method,giving values of RSDs of 0.11%,6.6%,5.1%and ranges of 0.32%,0.03%,0.03%,meeting requirments of difference of determined values specified by standard of HG/T 3271-2000.Recoveries found by the spiked recovery on the actual sample were kept in the ranges of 99.8%-100%,97.5%-101%,96.7%-102%,respectively.Compared with standard method HG/T3271-2000,the range of the determined values given by the proposed method was smaller.