1,5-二(2-羟基-5-氯苯)-3-氰基甲月替光度法测定水中锰

在pH 10的氨水-氯化铵缓冲溶液中,在聚乙二醇辛基苯基醚(OP-10)微乳液存在下,1,5-二(2-羟基-5-氯苯)-3-氰基甲月替(HCPCF)与锰形成稳定的络合物,据此建立了测定锰的分光光度法。实验表明,锰(Ⅱ)含量在0～1.0 mg/L范围内符合比尔定律,线性回归方程为A=0.002 8+0.006 9 ρ,相关系数为0.997 9,表观摩尔吸光系数为6.7×10⁴ L·mol^-1·cm^-1。方法用于水中锰的测定,测得结果与原子吸收光谱法相符合,相对标准偏差(n=6)为1.3%～2.0%,加标回收率为98%～103%。

Determination of manganese in water by 1,5-bi(2-hydroxy-5-chlorobenzene)-3-cyanoformazane spectrophotometry

In ammonia-ammonium chloride buffer solution at pH 10, 1,5-bi(2-hydroxy-5-chlorobenzene)-3-cyanoformazane(HCPCF) could react with manganese to form a stable complex in presence of polyethylene glycol octylphenol ether (OP-10) microemulsion. Based on this, a method for determination of manganese was established by spectrophotometry. The results showed that, Beer’s law was obeyed for manganese (Ⅱ) in the range of 0-1.0 mg/L. The linear regression equation was A=0.002 8+0.006 9ρ with correlation coefficient of 0.997 9. The apparent molar absorptivity was 6.7×10⁴ L·mol^-1·cm^-1. The proposed method was applied to the determination of manganese in water, and the results were consistent with those obtained by atomic absorption spectrometry. The relative standard deviation (n=6) was 1.3 %-2.0 %. The recoveries were between 98 % and 103 %.