|
|||||
|
|
Cu(II) Ion Complexation by Excess of β-cyclodextrin in Aqueous Alkaline Solutions |
|
| Authors: | Eugenijus Norkus Giedr? Grincien? Tapani Vuorinen Rimantas Vaitkus |
| Institution: | 1. Laboratory of Catalysis, Institute of Chemistry, A. Go?tauto 9, LT-2600, Vilnius, Lithuania 2. Department of Forest Products Technology, Helsinki University of Technology, Vuorimiehentie 1, FIN-02150, Espoo, Finland 3. Vilnius Pedagogical University, Studentu 39, LT-2034, Vilnius, Lithuania |
| Abstract: | Polarographic investigations of Cu(II) complexation in aqueous alkaline solutions containing an excess of β-cyclodextrin (β-CD) show that the complex formation begins at pH > 11, the concentration of free (uncomplexed) Cu(II) ions being in the range from ca. 10-12 to ca. 10-19 M, depending on β-CD concentration and pH. The formation of copper(II) 1:1 hydroxy-complex with β-cyclodextrin anion (CD2-) was observed at pH 11–14. The logarithm of the stability constant of CuCD(OH)2- 2 complex is 19.7 ± 0.2 (20 °C, ionic strength 1.0), the values of the molar extinction coefficient and of the diffusion coefficient of this complex are 50 M-1 cm-1 (λmax = 660 nm) and 1.0 × 10-6 cm2 s-1, respectively. |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ | |