Examination of complexing of vanadium(v) during extraction with N-(2-Hydroxy-5-Nonylbenzyl)-β, β-Dihydroxyethylamine

GRAPHICAL ABSTRACT

ABSTRACT

Extraction of vanadium(V) with the phenol-type tertiary amine N-(2-hydroxy-5-nonylbenzyl)-β,β-dihydroxyethylamine (NBEA) has been examined. The optimal extraction conditions have been determined. It was established that the extracted complex includes the cyclic tetramer V₄O₁₂⁴⁻ and four molecules The bands observed in the electronic spectra of the extracts are indicative of the formation of a chelate complex of vanadium(V) with N-(2-hydroxy-5-nonylbenzyl)-β,β-dihydroxyethylamine. The V-O bond in the extracted complex is formed owing to the dissociation of a proton from the phenol group, and the V-N bond is due to a lone-electron pair of nitrogen atom of the extractant. The chelate complex formed during the extraction of vanadium(V) with N-(2-hydroxy-5-nonylbenzyl)-β,β-dihydroxyethylamine is stable for more than a month and is not apt to reduction.

KEYWORDS:

• Extraction
• vanadium
• cyclic tetramer
• ionization energy
• chelate complex