Abstract
The completion of cobalt(II), nickel(II), copper(II), and zinc(II) with thiocyanate ions has been studied in micellar solutions of nonionic surfactant Triton X-100 by titration spectrophotometry and calorimetry. The complexation has been also studied by varying length of POE (polyoxyethylene) chain. With regard to Co(II), the [Co(NCS)4]2-, which hardy forms in aqueous phase, is extensively formed in micelles. With Zn(II), the [Zn(NCS)3]- and [Zn(NCS)4]2- are formed in micelles. With Ni(II), no completion occurs in micelles. In the case of Cu(II), the formation of [Cu(NCS)2] is concluded in both micelles and aqueous phase. The complercation behavior of [Co(NCS)4]2- and [Cu(NCS)2] depends significantly on the length of POE chain, suggesting that these complexes exist both in the relatively hydrophilic POE site and hydrophobic core site.
