|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1995 : ¥900,000 (Direct Cost : ¥900,000)
Fiscal Year 1994 : ¥1,200,000 (Direct Cost : ¥1,200,000)
We propose a metal ion-imprinted microsphere as a new metal ion-selective adsoebent. Imprinted microspheres were prepared by seed emulsion polymerization of divinylbenzene, stirene, butyl acrylate, and methacrylic acid. The imprinted structure was introduced on the carboxylated microsphere by surface-imprinting, in which the carboxyl groups were reorganized through complexation with metal ions on the surface (at pH 5.0) and then fixed by crosslinking polymerization in their specific orientation.
The Cu (II) , Ni (II) , and Co (II) -imprinted microspheres were obtained as submicron particles with average diameters of 0.55-0.60 mum. They were immediately used as a metal ion-selective adsorbent without any further treatment, such as grinding and sieving. The adsorption behaviors of metal ions were examined, and the imprinted effects were verified clearly. The imprinted microsheres adsorbed the corresponding guest ion more effectively than did unimprinted ones. Unimprinted and Cu (II) -imprinted microspheres were prepared under several pH (4.0,5.0,5.6,6.0) conditions in the surface-imprinting step. The maximum imprinting effect was provided by microspheres obtained at pH5.6.
Surface-imprinted resins were also prepared by emulsion polymerization using oleyl phenyl hydrogenphosphonate as a host surfactant, sodium dodecyl sulfate (SDS) as a co-surfactant and divinylbenzene as a resin matrix-forming monomer. The template-dependent selectivity was clearly demonstrated for Cu (II) , Zn (II) , and Cd (II). This phosphate-carrying resin would be promising for selective separation of rare earth metal and uranyl ions.