Spectroscopic investigation complex formation of tungsten with 2, 6-dithiol-4-methylphenol in the presence of aminophenols

Abstract

The mixed-ligand complexes of tungsten (VI) with 2, 6-dithiol-4-methylphenol (DTMP) in the presence of hydrophobic amines have been investigated by spectrophotometric method. The condition of complexing and extraction, physical-chemical and analytical characteristics of this complex have been found. From aminophenols 2(N, N-dime­thy­la­mino­me­thyl)-4-methylphenol (АP₁), 2(N,N-dime­thy­­la­mi­nomethyl)-4-chlorphenol (АP₂) and  2(N, N-di­me­thy­laminomethyl)-4-bromphenol (АP₃), were used.. It has been found that mixed-ligand complex were  formed in weakly acidic medium (pH 3.9 – 5.2). Maksimum of light absorp­tion observed at 476-480 nm. The calculated molar absorptivities (e_max) belong to the interval  (2.73-2.92)×10⁴. The extraction-photometric methods of tungsten determination have been worked out. The influence of diverse ions on determination of tungsten has been studied. The proposed methods have been successfully applied to determination of tungsten in steel, soil and plant samples.