关键词: 交联壳聚糖, 吸附, 含铀废水

Abstract: Taking the natural polymer compounds of chitosan as raw materials, the insoluble cross-linked chitosan was synthesized by the reaction of chitosan with epichlorohydrin under alkaline conditions as the adsorbent of uranium-bearing wastewater. The influence factors on adsorption of uranium were investigated in details, such as pH value, adsorbent dosage, uranium initial concentration, particle size and equilibrium of adsorption and the adsorption kinetics law of uranium on cross-linked chitosan were described. The results show that under the conditions of pH=3～5, adding 10 mg cross-linked chitosan, the adsorption equilibrium for the 50 mg/L uranium can be obtained after 160min of adsorption, and the adsorption removal efficiency of cross-linked chitosan for uranium was over 98.0%. The adsorption law of uranium on cross-linked chitosan followed the Langmuir model very well and the pseudo second-order kinetics model was used to describe the adsorption process. When the initial concentrations of uranium is 50 mg/L, the adsorption removal efficiency of chitosan and cross-linked chitosan for uranium is 87.4% and 98.0% respectively, and the absorbability of cross-linked chitosan was improved significantly.

Key words: Cross-linked chitosan, Adsorption, Uranium-bearing wastewater