微量分光光度法快速测定饮用水中硫酸盐

Determination of sulfate in drinking water by micro-spectrophotometry

目的建立一种快速测定饮用水中硫酸盐的微量分光光度法。方法基于硫酸钡比浊法原理,采用自主研发的可自动进样、比色、计算、清洗的微量自动分析仪及其配套试剂盒,对饮用水中硫酸盐进行测定。结果方法的线性范围为5 mg/L^80 mg/L,相关系数(r)为0.997 8,检出限为2.66 mg/L,RSD<1%,自来水加标回收率为89.5%~109.0%,对硫酸盐质控样品的测定结果均在标准定值范围内,相对误差为0.36%~0.91%。采用本法测定实际样品中的硫酸盐,其结果与国家标准方法基本一致。结论微量分光光度法测定饮用水中硫酸盐,操作简单快速、准确、精密度高,与国家标准比浊法相比,量程翻倍,试剂种类、样本用量及废液的生成大幅减少,更加环保,适合在村镇集中式供水单位推广使用。

Objective To establish a method of micro- spectrophotometry for the rapid determination of sulfate in drinking water. Methods Based on the principle of barium sulfate turbidimetric method,the sulfate was quantified by the domestic made trace automatic analyzer and matched colorimetric assay kit which can sample,calculate and clean automatically. Results The linear range of the method was 5 mg / L- 80 mg / L; the correlation coefficient was greater than 0. 997 8; the detection limit of the method was 2. 66 mg / L; the relative standard deviation（ RSD） was less than 1%; the recovery was 89. 5%- 109. 0%. The results of sulfate quality control samples were in the standard setting value range and the relative error were among 0. 36%-0. 91%. The samples results of the method were consistent with national standard method. Conclusion The micro- spectrophotometry for the detection of sulfate in drinking water is simple,fast,accurate and precise. Compared to the national standard method,the method has expanded linear range and reduced the amounts of chemical reagents,sample solution and waste liquid substantially. The method is green and suitable for the use in rural centralized water units.