Lead, copper, and cadmium were adsorbed onto calcium alginate beads containing the cell suspension discarded from a brewery. In the cell suspension, there were many cells under lysis. The cell-suspension immobilized beads were prepared by adding 0.6% (w/v) sodium alginate into the cell suspension from the brewery and then making the cell suspension fall dropwise into the swirling 1% (w/v) calcium alginate solution. The dry weight of insoluble solid in the cell suspension was 96 g dry weight/l and the dry density of the bead containing cell suspension was 140 g dry weight/l of the bead. The specific metal uptake of the cell-suspension immobilized bead was 23.7 mg Pb2+, 14.3 mg Cu2+, and 13.4 mg Cd2+/g bead dry weight, respectively. The cell-suspension immobilized beads retained the initial metal-uptake capacity after 20 repeated batches of adsorption and desorption, but the fraction of metal desorbed from the beads by 1M HCl solution was only 70% of the adsorbed metal. The beads, which had been contained for 14 successive days in the 0.5% (w/v) CaCl2 solution at 4 oC just after 20 cycles of adsorption/desorption, retained the initial metal-uptake capacity after 30 repeated cycles, and more than 90% of the copper and cadmium adsorbed on the beads was desorbed by the 1 M HCl solution.
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