Application of the Ion Pair of 2-(5-Bromo-2-pyridylazo)-5-diethylaminophenol and Ammonium Tetraphenylborate for Preconcentration of Trace Vanadium and Determination by Third Derivative Spectrophotometry

• 来源期刊: 中国化学（英文版）
• 年，卷（期）: 2002,（12）
• 页码范围: 1584-1590
• 页数: 7页
• 语种: 英文

摘要

Vanadium is quantitatively retained on 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol ( 5-Br- PADAP)-ammonium tetraphenylborate with microcrystalline naphthalene or by a column method in the pH range of 2.1-4.5 from a large volume of aqueous solutions of various samples. After filtration, the solid mass consisting of the vanadium complex and naphthalene was dissolved with 5 mL of dimethylformamide and the metal was determined by the third derivative spectrophotometry. Vanadium complex can alternatively be quantitatively adsorbed on ammonium tetraphenylborate-naphthalene adsorbent packed in a column and determined similarly. About 0.05 μg of vanadium can be concentrated in a column from 250 mL of aqueous sample, where its concentration is as lowas0.2 ng/mL. The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for the determination of trace amount of vanadium in various samples.