离子交换色谱-间接紫外光谱法测定水中4种还原性阴离子

Ion chromatographic determination of four reducing anions in water utilizing Indirect Photometric Detection

目的建立水中4种还原性阴离子的快速检测方法。方法水中4种还原性阴离子通过离子交换色谱分离柱后与高锰酸钾溶液混合,发生高锰酸钾褪色反应,采用间接紫外光谱法进行定量检测。结果在确定的色谱条件下,200μL进样,4种还原性阴离子的相对标准偏差在2.5%~5.7%,回收率在88.0%~102.5%间,相关系数均〉0.999。以3倍的信噪比计算,4种还原性阴离子检出限分别为亚砷酸钠0.10μmol、硫化钠0.27μmol、亚硫酸钠0.39μmol、草酸钠1.50μmol。结论建立的实验方法线性好,灵敏度高,检测时间较短,可应用于水中4种还原性阴离子的快速定量检测。

Objective To establish a method for determination of 4reducing anions in water.Methods A ion chromatography combined with spectrophotometer method was approached for simultaneous determination of 4reducing anions.The mixture was separated by isocratic elution and determinated by spectrophotometer due to the color fading reaction with potassium permanganate.Results With injection of 200μl,the recovery rate was 88.0%~102.5%,the relative standard deviation was2.5%~5.7%,the detection limits（S/N=3）was 0.10μmol for arsenite,0.27μmol for sulfide,0.39μmol for sulfite and 1.50μmol for oxalate,respectively.Conclusion The proposed method was applied successfully to the determination of 4reducing anions in water.