Heavy metal adsorption by microbial cells is an alternative to conventional methods of heavy metal removal and recovery from metal-bearing wastewater. The waste Saccharomyces cerevisiae is an inexpensive, relatively available source of biomass for heavy metal biosorption. Biosorption was investigated by free and immobilized-S. cerevisiae. The order of biosorption capacity was Pb>Cu>Cd with batch system. The biosorption parameters had been determined for Pb with free cells according to the Freundlich and Langmuir model. It was found that the data fitted reasonably well to the Freundlich model. The selective uptake of immobilized-S. cerevisiae was observed when all the metal ions were dissolved in a mixed metals solution(Pb, Cu, Cr and Cd). The biosorption of mixed metals solution by immobilized-cell was studied in packed bed reactor. The Pb uptake was investigated in particular, as it represents one of the most widely distributed heavy metals in water. We also tested the desorption of Pb from immobilized-cell by using HCl, H_2SO_4 and EDTA.

• Kab-Hwan Ahn(Dept. of Environmental Science & Technology, Jisan Junior College)
• Yong-Kook Shin(Korea Collection for, Type Cultures, Korea Research Institute of Bioscience and Biotechnology)
• Kuen-Hack Suh(Dept. of Chem. Eng., Pukyong National University)