Biosorption of cadmium(II) and lead(II) from aqueous solutions by fruiting body waste of fungusFlammulina velutipes

Abstract

The biosorption of Cd2+ and Pb2+ by fruiting body wastes of macrofungi Flammulina velutipes was studied. The factors affecting absorbtion including pH, initial metal concentration, biosorbent dosages and mutual competitive biosorption of both metal ions were focused. The sorption of Cd2+ and Pb2+ was increased with pH value from 2 to 6 and maximum biosorption was at pH 6. The quantity of Cd2+ and Pb2+ adsorbed increased with the initial concentration of metal ions and both metals removal gradually increased with the biosorbent dosage. There existed mutual competitive biosorption between Cd2+ and Pb2+ when they were in the same solution. The Langmuir isotherm model fitted both metal ions sorption data well in the experiment and the calculated maximum sorption capacity of Cd2+ and Pb2+ by F. velutipes was 8.4317 mg/g dry biomass with R 2 of 0.9228 and 18.3486 mg/g dry biomass with R 2 of 0.9280, respectively. Pseudo-first order equation fitted for adsorption data of Cd2+ with R 2 of 0.9504, while pseudo-second order equation more fitted for adsorption data of Pb2+ with R 2 of 0.9917.