环境水体中亚硫酸盐分析方法研究

Determination of Sulphite in Environmental Waters

研究发现,溴酸钠能够与劳氏紫发生褪色反应,而亚硫酸盐对此反应有催化作用,从而建立起测定亚硫酸盐的新方法。在上述最优实验条件下,SO32-浓度C介于5×10-8～2.5×10-6g/mL和2.5×10-6～1×10-4g/mL范围内与吸光强度(mV)呈良好的线性关系。该方法的检出限为1.7×10-8gm/L。对浓度为5×10-7g/mL和1×10-5g/mL的SO32-进行11次连续测定,计算得出相对标准偏差(RSD)分别为2.1%和3.3%。应用文章建立的新方法对河水水样中的SO32-进行分析,回收率在96.4%～104.8%,结果令人满意。

A kinetic method for the determination of sulphite based on catalytic effect on the reaction between sodium bromate and thionine in strongly acidic media was proposed. Under the optimal conditions, response to sulphite concentration was linear in the range of 5×10^-8-2.5×10^-6g/mL and 2.5×10^-6-1×10^-4g/mL, with the correlation coefficients of 0.995 and 0.997 respectively and detection limit of 1.7×10^-8g/mL. The relative standard deviation was 2.1% for 5×10^-7g/mL sulphite and 3.3% for 1×10^-5g/mL sulphite. The proposed method was applied to the determination, of sulphitein river water successfully, with recovery between 96.4% and 104.8%.