摘要
We prepared ethylenediaminetetraacetic acid(EDTA)-intercalated MgAl-layered double hydroxide(LDH-EDTA),then grafted acrylamide(AM)to the LDH-EDTA by a cross-linking method to yield a LDH-EDTA-AM composite;we then evaluated its adsorptive ability for Congo red(CR)and hexavalent chromium(Cr(Ⅵ))in single and binaiy adsorption systems.The adsorption process on LDH-EDTA-AM for CR and Cr(Ⅵ)achieved equilibrium quickly,and the removal efficiencies were minimally affected by initial pH.The maximum uptake quantities of CR and Cr(Ⅵ)on LDH-EDTAAM were 632.9 and 48.47 mg/g,respectively.In mixed systems,chromate removal was stimulated by the presence of CR,while the adsorption efficiency of C R was almost not influenced by coexisting Cr(Ⅵ).The mechanisms involved electrostatic attraction,surface complexation,and anion exchange for the adsorption of both hazardous pollutants.In the Cr(Ⅵ)adsorption process,reduction also took place.The removal efficiencies in real contaminated water were all higher than those in the laboratory solutions.
基金
This work was supported by the National Natural Science Foundation of China(Grant No.21577048).
