Equilibrium, kinetic and thermodynamic studies on biosorption of Pb(II) and Cd(II) from aqueous solution by fungus (Trametes versicolor) biomass

The biosorption characteristics of Pb(II) and Cd(II) ions from aqueous solution using the fungus (Trametes versicolor) biomass were investigated as a function of pH, biomass dosage, contact time, initial metal ion concentration and temperature. Langmuir and Freundlich models were applied to describe the biosorption of the metal ions by fungus (T. versicolor) biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The monolayer biosorption capacity of T. versicolor biomass for Pb(II) and Cd(II) ions was found to be 208.3 mg g−1 and 166.6 mg g−1, respectively. The calculated thermodynamic parameters (ΔG°, ΔH° and ΔS°) showed that the biosorption of both metal ions was feasible, spontaneous and endothermic at 303–323 K. Experimental data were also used to study biosorption kinetics using pseudo-first-order, pseudo-second-order and intraparticle diffusion kinetic models. The results showed that the biosorption processes of both metal ions followed well pseudo-second-order kinetics.