Adsorption of metal ions onto carboxylated microspheres synthesized by seeded emulsion polymerization

Carboxylated microspheres were synthesized by seeded emulsion polymerization of methacrylic acid, n-butylacrylate and styrene. The features of the microspheres such as composition, average particle diameter and particle distribution were examined by elemental analysis, FT-IR spectrum, particle grading analysis and scanning electron micrography. The manner of adsorption onto these microspheres in water suspension was studied for the metals Cu(II), Zn(II), Co(II), Ni(II) and Mn(II). The adsorption equilibrium was attained in less than 1 h. The microspheres could adsorb Cu(II) and Zn(II) selectively from weakly acidic solution (pH 5.6). The selectivity for Cu(II) among the divalent metal ions was comparable to those reported with Cu(II)-templated polymer resins.