Hybrid porous magnetic bentonite-chitosan beads for selective removal of radioactive cesium in water

Kexin Wang, Hui Ma, Shengyan Pu, Chun Yan, Miaoting Wang, Jing Yu, Xiaoke Wang, Wei Chu, Anatoly Zinchenko

Research output: Journal article publicationJournal articleAcademic researchpeer-review

66 Citations (Scopus)

Abstract

Easy-to-obtain magnetic bentonite-chitosan hybrid beads (Bn-CTS) were prepared by immobilizing bentonite within a porous structure of chitosan beads to achieve a hybrid adsorption effect for the removal of cesium ion (Cs+) from water. The hybrid adsorbent, which had a porous structure and abundant binding sites contributed by both chitosan and bentonite, ensured superb adsorption characteristics. The paramagnetic character of the beads enabled their facile separation for recycling. The chitosan/bentonite ratio, pH and contact time were optimized to achieve the optimal Cs+ efficiency, and the adsorption kinetics and isotherms were thoroughly discussed. The adsorption kinetics obeyed the pseudo-second-order model, and the best fitted equation for equilibrium data was the Langmuir isotherm model. The maximum adsorption capacity of the bentonite-chitosan beads was 57.1 mg g−1. The adsorbent had excellent selectivity towards Cs+ adsorption in the presence of abundant cations (Li+, Na+, K+ and Mg2+). The adsorbent was able to be recycled by treating the beads with 0.1 mol L−1 of MgCl2 to quantitatively desorb Cs+ from the beads. Overall, the magnetic bentonite-chitosan beads can be used as a highly efficient adsorbent for radioactive waste disposal and management.

Original languageEnglish
Pages (from-to)160-169
Number of pages10
JournalJournal of Hazardous Materials
Volume362
DOIs
Publication statusPublished - 15 Jan 2019

Keywords

  • Bentonite
  • Cesium
  • Hydrogel beads
  • Magnetic adsorbent
  • Radioactive wastewater

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Waste Management and Disposal
  • Pollution
  • Health, Toxicology and Mutagenesis

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