Bioremediation: Removal of Pb2+, Cr3+ and Cd2+ from Aqueous Solution using Immobilized Ficus sycomorus Leaves

Abstract

This study investigated the effectiveness of immobilized Ficus sycomorus leaves (IFSL) for the removal of Pb²⁺, Cr³⁺ and Cd²⁺ions from waste water. The immobilization of Ficus sycomorus leaves was achieved by entrapping it within a polymeric matrix of calcium alginate. Sorption capacity (in percentage) of IFSL was determined from the decrease in the concentration of aqueous solutions of Pb²⁺, Cr³⁺ and Cd²⁺ with reference to the final concentrations of the solutions obtained using atomic absorption spectrophotometer (AAS). IFSL exhibited the highest sorption capacity for Pb²⁺ (99.97±0.0011) followed by Cr³⁺ (93.76±0.0012) and the least for Cd²⁺ (87.72±0.0016). Experimental parameters that influence the sorption capacity of these heavy metal ions such as pH, contact time, ionic strength, and initial metal ion concentration were investigated. The result obtained shows that there was an increase in sorption capacity as the pH, contact time, and initial metal ion concentration increases, while there was a decrease in sorption capacity as ionic strength increases. These results show that IFSL can be an effective biosorbent for waste water treatment; hence, a cheap and cost saving technology for treatment of an aqueous solution.