Cibacron Blue F3GA-attached polyvinylbutyral microbeads as novel magnetic sorbents for removal of Cu(II), Cd(II) and Pb(II) ions

Magnetic polyvinylbutyral based microbeads containing 12.4 mu mol Cibacron Blue F3GA/g were used in the adsorption-desorption of some selected heavy metal ions, i.e., Cu(II), Cd(II) and Pb(II) from aqueous media containing different amounts of these ions (5-500 ppm) and at different pH values (2.0-8.0). Adsorption rates were high, and adsorption equilibria were reached in about 30 min. The maximum adsorptions of heavy metal ions onto the Cibacron Blue F3GA-attached affinity microbeads from their single solutions were 9.6 mg/g for Cu(II), 38.6 mg/g for Cd(Ui), 86.2 mg/g for Pb(II). When the heavy metal ions competed (in the case of the adsorption from their mixture) the amounts of adsorption were 6.5 mg/g for Cu(III), 20.3 mg/g for Cd(II) and 41.6 mg/g for Pb(II). Under non-competitive and competitive conditions the affinity order of ions was Pb(II)>Cd(II)>Cu(II). Desorption of heavy metal ions was achieved using 0.1 mol HNO3 in 30 min. It was observed that heavy metal ions could be repeatedly adsorbed and desorbed without significant loss in adsorption capacity. (C) 1998 Elsevier Science B.V.