• 文献标题:   Asymmetric polysaccharide-bound graphene electrode configuration with enhanced electrosorption performance for uranium (VI) ions
  • 文献类型:   Article
  • 作  者:   LIAO Y, YAN C, ZENG K, LIAO CL, WANG M
  • 作者关键词:   uranium vi, electrosorption, polysaccharide binder, coions expusion, graphene
  • 出版物名称:   CHEMICAL ENGINEERING JOURNAL
  • ISSN:   1385-8947 EI 1873-3212
  • 通讯作者地址:  
  • 被引频次:   17
  • DOI:   10.1016/j.cej.2021.130351 EA MAY 2021
  • 出版年:   2021

▎ 摘  要

As an energy-saving and facile technology, the potential of capacitive deionization (CDI) starts to surface in enrichment and recovery of uranium (U(VI)) from aqueous solutions. However, co-ion expulsion effect and poor surface wettability of electrode materials limit the eletrosorption performance. Here, polysaccharides xanthan gum (XG)-and chitosan (CS)-bound porous reduced graphene (RGH) electrodes were rationally designed, and then assembled into asymmetrical electrode configuration for U(VI) eletrosorption. Owing to the introduction of polysaccharide binders, the oppositely charged groups on the surface of cathode and anode weaken the co-ions exclusion effect as well as endow their superior surface hydrophilicity and electroconductivity, which facilitates the electrosorption for U(VI). Meanwhile, the negatively charged carboxylate groups could act as extra micro electric fields to attract U(VI) cations, and form stronge complexation between them. As a consequence, asym-metrical polysaccharide-bound RGH configuration gave rise to a larger removal ratio of 97.9% within 4 h at 1.2 V, as well as 2.5 times faster kinetics than symmetrical PVDF-bound RGH electrode configuration. Moreover, the accumulated adsorption capacity in six adsorption-desorption cycles of the former is up to 1413.0 mg g(-1), 75% higher than the latter, which is of practical significance and economic benefit for electrosorption application.