分光光度法测定环境水样中镁的研究

Study on Determining Mg in Environmental Water Sample by Spectrophotometry

研究了4-(2-羟基-4-硝基苯偶氮)-1-苯基-3-甲基吡唑啉酮(HNAPMP)与镁的显色反应,在硼砂—氢氧化钠(pH=10)缓冲介质中,乳化剂-OP存在下,HNAPMP与镁反应生成2∶1稳定络合物,λmax为525nm,ε为3 63×104L·mol-1·cm-1。镁含量在0—0 8mg/L内符合比耳定律,方法用于环境水样中镁的测定,结果令人满意。

This paper studys color reaction of HNAPMP with Mg. At the condition of pH=10 buffer solution, HNAPMP can react with cobalt and form a stable 2∶1 complex. After extracted by C_(18) solid-phase extraction colum and then eluted by alcohol, the complex can be detected at λ=525 nm. The molar absorpitivity is 3.63×10~4 L·mol^(-1)·cm^(-1), and the beer's law is obeyed in the Mg rang of 0 — 0.8 mg/L. It is satisfied that apply this method to determine Mg in environmental water sample.