A chitosan-based composite for adsorption of uranyl ions; mechanism, isothems, kinetics and thermodynamics


Senol Z. M.

INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES, vol.183, pp.1640-1648, 2021 (Journal Indexed in SCI) identifier

  • Publication Type: Article / Article
  • Volume: 183
  • Publication Date: 2021
  • Doi Number: 10.1016/j.ijbiomac.2021.05.130
  • Title of Journal : INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
  • Page Numbers: pp.1640-1648
  • Keywords: Chitosan, Sepiolite, Crosslinking agent, Composite beads, Adsorption mechanism, UO22+, SELECTIVE REMOVAL, AQUEOUS-SOLUTIONS, IMPRINTED RESIN, METHYLENE-BLUE, CU(II) IONS, BEADS, MICROSPHERES, ADSORBENT, SEPIOLITE, CELLULOSE

Abstract

The present paper describes a green and cost-effective approach to investigate chitosan-sepiolite (Ch-Sep) composite as an adsorbent for removal of UO22+ ions in aqueous solution. The Ch-Sep composite was prepared as a beads using with two cross-linking agents: tripolyphosphate (TPP) and epichlorohydrin (ECH). Their adsorption properties for the removal of UO(2)(2+ )ions in aqueous solution by batch experimental conditions were studied. The adsorptive removal processes of UO(2)(2+ )ions from aqueous solution were evaluated by Langmuir, Freundlich and Dubinin-Radushkevich isotherm models, and was found to be perfectly fit to the Langmuir model (R-2 = 0.971). The maximum adsorption capacity was 0220 mol kg(-1) at 25 degrees C from Langmuir isotherm model. Adsorption energy was 12.1 kJ mol(-1) indicating that the adsorption process was chemical. The adsorption kinetics followed the pseudo second order and infra particle diffusion models. The thermodynamics parameters of UO22+ ions removal from aqueous solution was confirmed spontaneous, endothermic and possible at higher temperatures behavior of adsorption process. The adsorption mechanism of UO(2)(2+ )ions onto Ch-Sep composite beads was investigated by FT-IR and SEM analysis. These findings revealed the effectiveness and potential of the newly synthesized Ch-Sep composite beads for the removal of UO22+ ions. (C) 2021 Elsevier B.V. All rights reserved.