Primary biosorption mechanism of lead (II) and cadmium (II) cations from aqueous solution by pomelo (Citrus maxima) fruit peels

Environ Sci Pollut Res Int. 2021 Dec;28(45):63504-63515. doi: 10.1007/s11356-020-10176-6. Epub 2020 Jul 27.

Abstract

The present work investigates the primary adsorption mechanisms of lead (II) and cadmium (II) cations onto pomelo fruit peel (PFP) from aqueous solution. pH, adsorption time, ion strength, and initial metal cation concentrations, which are factors affecting the uptake of these cations, are investigated. Results show that pH and ion strengths strongly affect the removal of these cations from aqueous solution. Different isotherm adsorption models, such as Langmuir, Freundlich, and Sips, are utilized to fit the experimental data in order to determine the adsorption in nature. The Langmuir monolayer adsorption capacities are found to be 47.18 mg/g for lead (II) and 13.35 mg/g for cadmium (II). Kinetic and thermodynamic studies based on a combination of FT-IR and TG-DSC spectroscopies demonstrate that electrostatic attraction plays a primary adsorption mechanism of lead (II) and cadmium (II) cations onto pomelo fruit peel.

Keywords: Adsorption mechanism; Biomaterial; Electrostatic attraction; Pomelo fruit peel (PFP); n-d interaction.

MeSH terms

  • Adsorption
  • Cadmium
  • Cations
  • Citrus*
  • Fruit
  • Hydrogen-Ion Concentration
  • Kinetics
  • Lead
  • Spectroscopy, Fourier Transform Infrared
  • Water Pollutants, Chemical*

Substances

  • Cations
  • Water Pollutants, Chemical
  • Cadmium
  • Lead