The removal of Pb(II) by Phanerochaete chrysosporium

The removal of Pb(II) by live, resting and dead cells of a lignolytic white-rot fungus, Phanerochaete chrysosporium was investigated. Kinetic studies revealed the fact that adsorption is a two-stage process: a very rapid surface adsorption within the first hour and a slow intracellular diffusion during 2 h of metal exposure. The results showed that the resting cells were able to uptake up to 80 mg Pb(II)/g dry cell. The saturation sorption capacities of live and dead cells were 9 and 20 mg Pb(II)/g dry cell, respectively. The biomass originated from different growth phases and exhibited different adsorption capacities for Pb(II). It appeared that the young resting cells held higher Pb(II) adsorption capacities than old ones. Acid and alkali pre-treatments of the old resting cells increased the sorption capacity; although the capacity of virgin young fungi was never attained. Acid treatment of the young cells reduced the adsorption capacity remarkably; however, alkali treatment improved it. (C) 2000 Elsevier Science Ltd. All rights reserved.