Adsorption of Co2+ and Sr2+ in aqueous solution by a novel fibrous chitosan biosorbent

Abstract

In this study, a novel fibrous chitosan biosorbent was prepared using LiOH/KOH/urea/H2O (4.5:7:8:80.5 by weight) as spinning solvent. The fibrous chitosan exhibited a higher adsorption capacity and a faster adsorption rate for Co2+ and Sr2+, compared with spherical chitosan due to its high specific surface area (16.9 m2 g−1), uniform fineness (24.1 μm), and good mechanical strength. The adsorption capacity of fibrous chitosan for Co2+ and Sr2+ was 31.3 mg g−1 and 20.0 mg g−1, respectively, which was higher than that of spherical chitosan (22.5 mg g−1for Co2+ and 8.9 mg g−1 for Sr2+). The coordination between –NH2/-OH of chitosan and the nuclide ions was the rate-limiting step. The improvement of adsorption performance was due to the higher specific surface area which increased the exposure degree of functional groups (adsorptive sites). This new wet-spun fibrous chitosan biosorbent showed great potential in the adsorptive removal of nuclides ions from aqueous solution.