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Спектрофотометрическими методами изучена реакция комплексообразования вольфрама с 2-гидрокси-5-бромтиофенолом в присутствии аминофенолов. Из аминофенолов использованы 2-(N,N-диметиламинометил)-4-метилфенол, 2-(N, N-диметиламинометил)-4хлорфенол, 2-(N, N-диметиламинометил)-4-бромфенол. Найдены оптимальные условия образования и экстракции разнолигандных соединений и установлены соотношения компонентов в комплексах. Было установлено, что разнолигандные комплексы образуются в слабокислой среде (рН опт =3.4-4.8). Максимум в спектре светопоглощения наблюдается при λ=475-485 нм. Молярный коэффициент светопоглощения равен ε =(2.6-2.8)× 10 4. На основании полученных данных разработаны фотометрические методики определения вольфрама в сталях различных марок.

The interaction of tungsten(VI) with 2-hydroxy-5-bromothiophenol (HBTP) in the presence of aminophenols (APs)was studied as follows:(N,N-diethylaminomethylthio)-4-methoxyphenol (AP 1), 2-(N,N-dibuthylaminomethylthio)-4-methoxyphenol (AP 2), 2,6-bis-(N,Ndimethylaminomethyl)-4-methylphenol (AP 3), 2,6-bis-(N,N-dimethylaminomethyl)-4-chlorophenol (AP 4), 2-(N,N-dimethylaminomethyl)-4-methylphenol (AP 5), 2-(N,N-diethylaminomethyl)-4-bromophenol (AP 6) and 4-chloro-2-(N,N-dimethylaminomethyl)-6-thiophenylmethylphenol (AP 7).The obtained ternary complexes have a composition of 1:2:2 (W:HBTP:AP) or 1:2:1 (AP 3 and AP 4). The optimum conditions for their formation and subsequent solvent extraction were found: organic solvent (chloroform), pH (4.1-5.6), concentration of reagents and extraction time. Degrees of extraction made up 98.1-98.6%. The complexes have absorption maximum at 470-482 nm and molar absorptivity coefficients ranged between (2.6-3.9)10 4. The Beer's law is observed in the range of concentrations of tungsten 0.2-16 µg/ml.

The complexation reactions of nickel (II) with 2-hydroxythiophenol and its derivatives (2,5- dihydroxythiophenol, 2-hydroxy-5-chlorothiophenol, 2-hydroxy-5-bromothiophenol, and 2-hydroxy-5- iodothiophenol) in the presence of hydrophobic amines were studied by spectrophotometric methods. Aniline and N, N-dimethylaniline were used as hydrophobic amines. It found that mixed-ligand complexes (MLC) are formed in a weakly acidic medium (pH 2.3-8.0). The maximum in the light absorption spectrum of the complexes is observed at λ = 620-650 nm. The molar coefficients of light absorption are (4.1-4.3)×104 . The best extractants were chloroform, dichloroethane and carbon tetrachloride. With a single extraction with chloroform, 97.8-98.4% of nickel is extracted in the form of MLC. Based on the data obtained, photometric methods for the determination of nickel in various objects were developed.

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