Co-APDC共沉淀-分光光度法测定工业废水中Cr(Ⅲ)

DETERMINATION OF Cr(Ⅲ)IN INDUSTRIAL WASTEWATER BY Co—APDC CHELATE COPRECIPITAION AND PHOTOMETRIC METHOD

在pH2.5条件下,采用Co—APDC共沉淀把Cr(Ⅵ)从样品中富集与Cr(Ⅲ)完全分离,滤液中的Cr(Ⅲ)用光度法测定。本方法回收率大于85％,重现性好,相对标准偏差小于2％。本法适用于工业废水中Cr(Ⅲ)的测定。

Cr(Ⅵ) can be concentrated from a sample by coprecipitation with Co—APDC method, but nct for Cr(Ⅲ). Cr(Ⅲ) in filterate solutim can be determined by photometric measure. The recovery is more than 85% at pH2.5 in which Cr(Ⅵ) is competely separated from Cr(Ⅲ), This velue is quantitative and repr Ducikle. R S D is Iess than 2%. Therefore the present method is a useful technique for the determination of Cr(Ⅲ) in industrial wastewater.