Botrytis cinerea as a new fungal biosorbent for removal of Pb(II) from aqueous solutions

Pb(II) ions were found to be accumulated extracellularly on the surface of Botrytis cinerea. The rate and extent of accumulation were affected by pH, contact time and initial Pb(II) ion concentrations. The Pb(II) sorption capacities of heat inactivated, detergent, NaOH, DMSO and AcOH pretreated B. cinerea cells were determined as 107.10 +/- 1.87, 57.50 +/- 2.42, 51.73 +/- 1.19, 46.63 +/- 3.22 and 30.00 +/- 2.23 mg/g, respectively, at initial Pb(H) ion concentration of 350 mg/dm(3) and optimum conditions of pH 4.0 and contact time of 90 min. The biosorbent was regenerated using 10 mM HCl solution, with up to 97% recovery and reused five times in biosorption-desorption cycles successively. The influence of Cu(II), Cd(II) and Ni(II) co-cations on Pb(II) biosorption capacity of heat inactivated B. cinerea biomass in binary and multimetal systems was evaluated and biosorption capacity of the Pb(II) ions was found to be reduced by the presence of the other competing metal ions. Langmuir adsorption isotherm model was used to describe the biosorption of Pb(II) ions by B. cinerea. The nature of the possible cell-metal ions interactions was also evaluated by FTIR, SEM and EDAX analysis. These examinations indicated the involvement of -COOH, -OH and -NH groups in the biosorption process and that Pb(H) ions were accumulated as crystals looking like "billiard balls" over the surface of B. cinerea cells. (c) 2005 Elsevier B.V. All rights reserved.