Pb2+ and Cr3+ uptake capacity by Sargassum horneri was 185.5㎎ Pb2+/g biomass and 102.6㎎ Cr3-/g biomass, respectively. An adsorption equilibria were reached within about 0.5 hr for Pb2+ and 1 hr for Cr3+. The adsorption parameters for Pb2+ and Cr3+, were determined according to Langmuir and Freundlich model. With an increase in pH values of 2 to 5, Pb2+ uptake was increased, however Cr3+ uptake was constant. The selectivity of mixture solution showed the uptake order of Pb2+>Cu2+>Cr3+>Cd2+. Pb2+ and Cr3+ adsorbed by S. horneri could be recovered from 0.1M HCl, 0.1M HNO3 and 0.1M EDTA by desorption process, and the efficiency of Pb2+ desorption was above 98%, whereas the efficiency of Cr3+ desorption was below 34%.

Heavy metal ions in water were removed using algal biomass as adsorbents. Absorbents were dried for 3 days, ground them by 40∼60 mesh and then were swelled in a buffer solution for 1hr. After being packed in the column, commercially available standard solution of Cd(Ⅱ) and Pb(Ⅱ) ions were diluted to get the suitable concentration and then it was eluted with the rate of 1 ㎖/min. Heavy metals on the adsorbents were recovered with nitric acid. More amounts of Cd(Ⅱ) or Pb(Ⅱ) ions in green algae, Ulva pertusa, than in brown algae, Sargassum hornerl, were adsorbed. Pb(Ⅱ) ion was adsorbed more than Cd(Ⅱ) ion in both algae. The pH effect of adsorbed amounts of Cd(Ⅱ), Pb(Ⅱ) ions on the biomass was shown the following order ; pH 10.5 > 8.5 > 7.0 > 5.5 > 3.5. Recovery ratio of metal ions from algae is shown higher in acidic or neural conditions than It in alkalis ones. Pb(Ⅱ) ion is recovered relatively more than Cd(Ⅱ) ion in our system.