Batch removal of lead ions from aquatic solutions by polyethyleneglycol-methacrylate gel beads carrying Cibacron Blue F3GA

Polyethyleneglycolmethacrylate [PEG-MA] gel beads (100-120 mu m in diameter ) carrying Cibacron Blue F3GA (42.6 mu mol g(-1) polymer) were prepared for the removal of Pb(II) ions from aqueous solutions containing different amo unt of these ions (10-600 mg l(-1)) and at different pH values (2.0-6.4). F b(II) adsorption capacity increases with the time during the first 20 min a nd then levels off toward the equilibrium adsorption capacity. Adsorption o f Pb(ID ions on the unmodified PEG-MA gel beads was zero. Cibacron Blue F3G A-immobilisation significantly increased the Pbm) adsorption (23.3 mg g(-1) polymer). Langmuir adsorption model was found to be applicaple in interpret ing lead adsorption by Cibacron Blue F3GA-immobilised PEG-MA gel beads. The adsorption of Pb(II) ions increased with increasing pH and reached a plate au value at around pH 5.0. The optimal pH range for Pb(II) adsorption was s hown to be from 5.0 to 6.0. PEG-MA gel beads can be regenerated by washing with a solution of nitric acid (0.1 M). The maximum regeneration value was as high as 98%. These PEG-MA gel beads are suitable for repeated use for mo re than three adsorption-desorption cycles without considerable loss of ads orption capacity.