Biosorption of lead from aqueous solutions by algae biomass: optimization and modeling

The present work represents the biosorption of lead from aqueous solution by using mixed-culture of algae biomass. The effect of four numerical independent variables (initial pH, biosorbent dosage, contact time, and initial concentration of lead) on the lead removal efficiency were investigated. The operational conditions were statistically optimized using central composite design (CCD) through response surface methodology (RSM). The maximum Pb removal was 95.43% at conditions including, pH of 6, 110 min of contact time, and 5.52 g/L of adsorbent dosage and 100 mg/L concentration of Pb. Adsorption kinetics follows the pseudo-second-order model and equilibrium is well described by Freundlich isotherm.