摘要：

建立了一种适用于含锌工业用水中痕量总铁测定的分光光度方法.在pH=9.00的条件下,用紫脲酸铵掩蔽Zn²⁺,用邻苯二酚紫与Fe²⁺反应生成蓝色络合物,以预先用邻菲罗啉掩蔽了Fe²⁺的显色体系为参比,605 nm处的吸光度与样品溶液中0.02~0.6 mg/L的Fe²⁺呈良好的线性关系,灵敏度约为邻菲罗啉法的5倍,检出限0.012 mg/L,加标回收率97.0%~100%,相对标准偏差1.16%.方法具有较高的灵敏度、准确度和重现性.

关键词: 总铁, 工业用水, 邻苯二酚紫, 分光光度法, 紫脲酸铵

Abstract:

A spectrophotometry method suitable for the determination of trace total iron in industrial water containing Zn²⁺ has been established. In the buffer solution when pH=9.00, murexide is used for masking Zn²⁺ and the reaction of pyrocatechol violet with Fe²⁺ forms a blue complex. Taking the chromagenic system whose Fe²⁺ has been masked by phenanthroline as reference solution,it is found that there is a good linear relationship between the absorbance of 605 nm and Fe²⁺ whose concentration is in the range of 0.02-0.6 mg/L in the sample solution. Meanwhile,the sensitivity of pyrocatechol violet spectrophotometry is about 5 times as much as that of phenanthroline spectrophotometry,detection limit is 0.012 mg/L,standard recovery rates are from 97% to 100%,and relative standard deviation is 1.16%. The results indicate that the method has superior sensitivity,accuracy and reproducibility.

Key words: total iron, industrial water, pyrocatechol violet, spectrophotometry, murexide

中图分类号: 

• O657.32