用连苯三酚分光光度法测定不同氧化态的钒。

Spectrophotometric determination of vanadium in different oxidation states with pyrogallol.

作者信息

Iranpoor N, Maleki N, Razi S, Safavi A

机构信息

Department of Chemistry, College of Sciences, Shiraz University, Shiraz, Iran.

出版信息

Talanta. 1992 Mar;39(3):281-4. doi: 10.1016/0039-9140(92)80033-a.

DOI:10.1016/0039-9140(92)80033-a

PMID:18965375

Abstract

Determination of vanadium at low concentrations is easily performed with pyrogallol as a ligand which forms a bluish-violet complex with vanadium(III), (IV) or (V). The colour of the bluish-violet complex (lambda(max) = 580 nm) contrasts well with the colour of both pyrogallol and vanadium. The complexes are stable for several hours. Beer's law is obeyed over the range 0-14 mug/ml vanadium at pH 6. The apparent molar absorptivity at 580 nm is (7.75 +/- 0.25) x 10(3)1.mole(-1).cm(-1). The effects of diverse ions on the determination of vanadium have been fully studied. Only Mo(VI) and W(VI) interfere seriously. The method is selective, sensitive and can be applied to the determination of total vanadium in a variety of samples.

摘要

以连苯三酚作为配体可轻松测定低浓度的钒，连苯三酚能与钒（III）、（IV）或（V）形成蓝紫色络合物。蓝紫色络合物（最大吸收波长λ(max)=580nm）的颜色与连苯三酚和钒的颜色形成鲜明对比。这些络合物在数小时内稳定。在pH值为6时，钒浓度在0 - 14μg/ml范围内符合比尔定律。580nm处的表观摩尔吸光率为(7.75±0.25)×10³l·mol⁻¹·cm⁻¹。已全面研究了多种离子对钒测定的影响。只有钼（VI）和钨（VI）有严重干扰。该方法具有选择性、灵敏性，可用于测定多种样品中的总钒。