Highly efficient removal of toxic Pb2+ from wastewater by an alginate-chitosan hybrid adsorbent: Highly efficient removal of toxic Pb2+ from wastewater by an alginate-chitosan hybrid adsorbent

BACKGROUNDIn this study, a low-cost and environment-friendly alginate-chitosan hybrid adsorbent (depicted as Alg-Chi) was developed for the removal of Pb2+ from water. RESULTSExperimental results showed that the Alg-Chi exhibits high selectivity and affinity for Pb2+. The selectivity coefficients of the Alg-Chi for Pb2+/Cr3+, Pb2+/Co2+ Pb2+/Cd2+, Pb2+/Zn2+, and Pb2+/Cu2+ are all >5. It can uptake 96.8% of Pb2+ from Pb2+-containing solutions (1.5mmolL(-1)), and the maximum adsorption capacity for Pb2+ reaches 468.5mgg(-1), which is higher than that of most reported adsorbents for Pb2+. Moreover, the Alg-Chi can also be regenerated via simple acid elution and used repeatedly without loss in adsorption ability. CONCLUSIONSAnalysis of the adsorption mechanism indicated that the Alg-Chi adsorbed Pb2+ mainly through ion exchange and chemical coordination. Green and low-cost raw materials, simple preparation process, efficient removal efficiency and recyclable, these characteristics give the synthetic Alg-Chi broad application prospects in the field of Pb2+-containing wastewater treatment. (c) 2018 Society of Chemical Industry