Bio-modified magnetic nanoparticles with Terminalia arjuna bark extract for the removal of methylene blue and lead (II) from simulated wastewater

Chemosphere. 2022 Mar;291(Pt 2):132673. doi: 10.1016/j.chemosphere.2021.132673. Epub 2021 Nov 1.

Abstract

This study reports a greener, cheaper and convenient approach to synthesize Terminalia arjuna bark extract coated magnetite nanoparticles (TA@MNPs) using the co-precipitation method and efficient removal of methylene blue (MB) and lead ions [Pb(II)] from simulated wastewater. The synthesized nanoparticles (NPs) were characterized by various techniques such as DLS, XRD, FTIR, HRTEM, AGM, and TGA. From TGA analysis, TA@MNPs was found to be stable even after 500 °C. Using the batch method, maximum removal was achieved at pH 9.0 for MB and pH 3.0 for Pb(II) solutions, respectively. Adsorption study showed that TA@MNPs followed pseudo-second-order kinetics by both adsorbates while isotherm modeling towards adsorption of Pb(II) and MB exhibited Langmuir and Freundlich isotherm respectively. The maximum adsorption capacity for Pb(II) on TA@MNPs was 210.5 mg g-1. The thermodynamic study proved the spontaneity of the physisorption process. Regeneration studies were also performed using five different eluents for the two adsorbents. Overall, TA@MNPs effectively removed pollutants from wastewater and thus could be potentially useful in providing clean water in a cheaper way.

Keywords: Lead adsorption; Magnetite nanoparticles; Methylene blue; Simulated wastewater; Terminalia arjuna.

MeSH terms

  • Adsorption
  • Hydrogen-Ion Concentration
  • Kinetics
  • Lead
  • Magnetite Nanoparticles*
  • Methylene Blue
  • Plant Bark / chemistry
  • Plant Extracts
  • Terminalia*
  • Wastewater
  • Water Pollutants, Chemical* / analysis
  • Water Purification*

Substances

  • Magnetite Nanoparticles
  • Plant Extracts
  • Waste Water
  • Water Pollutants, Chemical
  • Lead
  • Methylene Blue