萃取催化动力学光度法同时测定痕量铁(Ⅲ)和钒(Ⅴ)的研究

Simultaneous Determination of Trace Iron(Ⅲ) and Vanadium(Ⅴ) by Extraction Catalytic Kinetic Spectrophotometry

研究了在 p H5 .5的 Na Ac- HAc介质中 ,铁 ( )、钒 ( )催化溴酸钾氧化邻氨基酚显色的指示反应 ,用萃取平衡控制反应时间和水相中邻氨基酚的浓度及反应程度 ,通过测量 41 8nm处有机相的吸光度 ,建立了萃取催化动力学光度法同时测定痕量铁 ( )、钒 ( )的新方法。测定铁 ( )、钒 ( )的线性范围分别为 0 .0 5 - 2 0 μg/L和 0 - 1 0 0 μg/L;检出限分别为 3.2× 1 0 - 7g/L和 1 .3× 1 0 - 6g/L。用于测定环境水样及废水中的铁 ( )、钒 ( ) ,结果与 AAS法相符。

A new extraction catalytic kinetic spectrophotometric method used for the simultaneous determination of trace iron(Ⅲ) and vanadium(Ⅴ) has been described.It is based on the iron(Ⅲ) and vanadium(Ⅴ) catalyzed oxidation of o aminophenol by potassium bromate in HAc NaAc buffer medium at pH5.5.The reaction time,concentration of o aminophenol in aqueous phase and degree of reaction are controlled by extraction equilibrium.The absorbance of organic phase is measured at 418nm.The linear range of the method is 0.05—20μg/L for Fe(Ⅲ) and 0—0.1mg/L for V(Ⅴ),the detection limit for Fe(Ⅲ) is 3.2×10 -7 g/L and for V(Ⅴ) is 1.3×10 -6 g/L.The method has been applied to the determination of Fe(Ⅲ) and V(Ⅴ) in natural water and waste water,and the results obtained are well in agreement with AAS method.