采用亚甲基蓝分光光度法测定水中硫化物的探讨

Discussion on the Determination of Sulfide Content in the Water by Methylene Blue Spectrophometry

探讨了影响国标法测定水中硫化物准确度的主要影响因素。研究表明:为减少干扰,反应温度设置为20±2℃,显色反应时间设置为10min较佳,在该条件下,方法校准曲线具有良好的线性,相关系数>0.999,加标回收率为90.0%~101%,相对标准偏差(RSD)<3.7%(n=6)。质控样的测量结果均在保证值范围内,说明实验室监测能力处于受控状态。

The paper discussed the main factors, which influenced greatly the accuracy of the analysis result for the national standard. In order to reduce the interference, the experimental results showed that the optimal operating conditions, reaction temperature（20 ± 2） ℃,chromogenic reaction time 10 min. Under the better condition, sulfide content in the surface water was determined by drawing the calibration curve, the experimental results showed that the method had good linear relationship with the correlation coefficient more than 0.999, the recovery was 90.0% ~ 101%, the relative standard deviation of determination results was less than 3.7%（n = 6）. Sulfide content in the water quality control samples was consistent with the reference value,the experimental results which was reliable and effective, indicated that the laboratory detection ability was under controlled.