Biosorption of Pb2+ and Cu2+ in aqueous solutions using agricultural wastes

This study aimed to determine and compare the adsorptive capacity of Pb2+ and Cu2+ in simulated wastewater onto three agricultural wastes The adsorption capacities of Pb2+ onto the agricultural wastes can be arranged as Litchi chinensis (4.30 mg of sorbate per g of sorbent (mg g(-1)), 85.68% adsorption) > Bambusa vulgaris (3.83 mg g(-1), 76.19% adsorption) > Annona squamosa (2.70 mg g(-1), 53.66% adsorption) while the adsorption capacities of Cu2+ onto the same agricultural wastes can be arranged in the order: Bambusa vulgaris (3.86 mg g(-1), 77.17% adsorption) > Annona squamosal (3.58 mg g(-1), 71.58% adsorption) > Litchi chinensis (3.42 mg g(-1), 68.32% adsorption). The biosorbents had relatively higher adsorptive capacities with Cu2+ as compared to that of Pb2+ except for Litchi chinensis. Although the results show lower adsorptive capacity as compared to a number of treated agricultural wastes showing 80% up to almost 100% adsorption of Pb2+ and Cu2+, the results show that Annona squamosa, Bamubusa vulgaris, and Litchi chinensis are potential biosorbents and promote sustainable treatment process.