Effective decontamination of As(V), Hg(II), and U(VI) toxic ions from water using novel muscovite/zeolite aluminosilicate composite: adsorption behavior and mechanism

Environ Sci Pollut Res Int. 2020 Apr;27(12):13247-13260. doi: 10.1007/s11356-020-07945-8. Epub 2020 Feb 4.

Abstract

Muscovite/phillipsitic zeolite was introduced as a novel inorganic composite of stunning adsorption properties. The composite was investigated in the uptake reactions of Hg(II), As(V), and U(VI) as highly toxic water contaminants considering different adsorption factors. The adsorption properties of muscovite/phillipsitic zeolite are highly dependent on the pH values and the best decontamination percentages can be obtained at pH 4, pH 5, and pH 5 for Hg(II), As(V), and U(VI), respectively. The kinetic studies demonstrated adsorption equilibrium for Hg(II), As(V), and U(VI) after 360 min, 300 min, and 360 min, respectively. The equilibrium modeling suggested monolayer uptake for all the metals and represented mainly by the Langmuir model considering both the values of determination coefficient and chi-squared (χ2). The estimated maximum capacities are 117 mg/g (Hg(II)), 122.5 mg/g (As(V)), and 138.5 mg/g (U(VI)) which are higher values than several studied adsorbents. The Dubinin-Radushkevich adsorption energies of Hg(II) (19.4 kJ/mol), As(V) (25.6 kJ/mol), and U(VI) (26.47 kJ/mol) signify chemical adsorption mechanisms and close to the obtained values for the ion-exchange process. Additionally, the composite is of high reusability properties and was applied effectively for five decontamination cycles. Graphical abstract.

Keywords: Adsorption; Composite; Heavy metals; Mechanism; Muscovite; Phillipsite zeolite.

MeSH terms

  • Adsorption
  • Aluminum Silicates
  • Decontamination
  • Hydrogen-Ion Concentration
  • Ions
  • Kinetics
  • Mercury*
  • Water
  • Water Pollutants, Chemical*
  • Water Purification*
  • Zeolites*

Substances

  • Aluminum Silicates
  • Ions
  • Water Pollutants, Chemical
  • muscovite
  • Water
  • Zeolites
  • aluminosilicate
  • Mercury