国标法测定地表水中阴离子表面活性剂方法优化  

Optimization of Determination of Anionic Surfactant in Surface Water by National Standard Method

作　　者：窦艳艳[1] 王保勤[1] 沈敏[1] 徐荣[1] Dou Yanyan;Wang Baoqin;Shen Min;Xu Rong(Nanjing Environmental Monitoring Center, Nanjing 210013, China)

机构地区：[1]南京市环境监测中心站,南京210013

出　　处：《化学分析计量》2017年第3期88-91,共4页Chemical Analysis And Meterage

摘　　要：对GB/T 7494–1987测定地表水中阴离子表面活性剂含量的方法进行优化。对萃取次数、磷酸二氢钠溶液反洗以及pH调节等进行了试验研究,将萃取用的三氯甲烷总量降为25 mL,两次萃取定容后一次反洗。结果表明,萃取两次可以满足分析需求,反洗能够有效去除亚硝酸盐氮等离子干扰,中性地表水样品无需调节pH,非中性样品须调为中性后测定。方法优化后线性良好,线性相关系数大于0.999,检出限为0.012 mg/L。测定结果的相对标准偏差为0.8%~3.3%(n=6),加标回收率为92.0%~110.0%。优化后方法满足地表水分析要求,能有效降低三氯甲烷用量并简化分析步骤。The method for determination of anionic surfactant in surface water according to GB/T7494-1987was optimized.The extraction times,pH regulation and abstersion using sodium dihydrogen phosphate were studied.The dosage of chloroform was reduced to25mL followed by two times extraction and one time abstersion.The results showed that two times extraction was sufficient for analysis,and abstersion using sodium dihydrogen phosphate could efficiently reduce the interferece of ions such as nitrite.The pH adjustment was needed for acidic and alkaline surface water samples,while was not needed for neutral surface water sample.The optimized method had fine linearity,linear correlation coefficient was more than0.999,and the detection limit was0.012mg/L.The relative standard deviation of samples detection results was0.8%-3.3%(n=6),the recovery rates of standard addition ranged from92.0%to110.0%.The optimized method can meet the requirements of environmental sample analysis while reducing the chloroform dosage and simplifying the analytical procedures.

关 键 词：阴离子表面活性剂 方法优化 地表水 国标法 亚硝酸盐氮 

分 类 号：O661[理学—分析化学]