铬络合物的固相萃取富集和分光光度法测定

Solid-Phase Extraction Preconcentrationof Chromium Complex and Its Determinationby Spectrophotometry

本文提出了用聚乙烯粉末固相萃取铬络合物的方法。在强酸性介质中，Ｃｒ（Ⅵ）与二苯碳酰二肼发生氧化还原反应，反应产物能结合生成稳定的络合物。这种络合物能吸附富集在填充有聚乙烯粉末的萃取柱上，并能用少量甲醇从柱上洗脱下来。文章详细介绍了萃取步骤及各种因素对固相萃取的影响。该富集方法取材、操作简单，已用于地质样品中铬的分析。

A solid-phase extraction method for thechromium cornplex using polyethylene as sor-bent is described.In a strongly acidic mediuma redox reaction between Cr (Ⅵ)anddiphenylcarbazide occurs,the resultant prod-uct is a stable complex. This complex can beadsorbed on the polyethylene extraction co-humn and eluted off bv methanol.The extrac-tion procedure and effects of various factors onthe solid-phase extraction were discussed inthis paper. The material needed and oprationof this preconcentration method are simple andthe method has been used for the determina-tion of chromium in geological samples.