Biosorption properties of pretreated sporopollenin biomass for lead(II) and copper(II): Application of response surface methodology

The role of pretreated sporopollenin (PSp) biomass in M(II) (M = Pb, Cu) removal from aqueous solutions was investigated by batch biosorption technique. The chemical properties and morphology of the biosorbent were characterized by means of FT-IR and SEM-EDX techniques. Influence of various operating parameters like pH, contact time, biosorbent dose and initial concentration on biosorption process were optimized by using a quadratic model Box-Behnken design using response surface methodology. The results indicated that Pb(II) and Cu(II) sorption on PSp was strongly dependent on pH. The experimental equilibrium data was analyzed with three isotherm models and the sorption data was better fitted to Langmuir isotherm model, and the order of maximum biosorption capacity (q(max)) was Pb(II) (6.10 mg g(-1))> Cu(II) (4.84 mg g(-1)). FTIR and SEM-EDX was used to identify the biosorption mechanism and it was confirmed from SEM-EDX that metal ions were present in the PSp biomass after biosorption. These results are important for estimating and optimizing the removal of metal ions by PSp biomass. The results demonstrated that PSp was a economic and eco-friendly biosorbent possessed strong sorption characteristics for Pb(II) and Cu(II) ions. (C) 2014 Elsevier B.V. All rights reserved.