African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12370

Full Length Research Paper

Adsorption of copper (II) ions onto raw Globimetula oreophila (Afomo ori koko) leaves

Chijioke John Ajaelu
  • Chijioke John Ajaelu
  • Department of Chemistry and Industrial Chemistry, Bowen University, Iwo, Osun State, Nigeria.
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Esther Oremeiyi Faboro
  • Esther Oremeiyi Faboro
  • Department of Chemistry and Industrial Chemistry, Bowen University, Iwo, Osun State, Nigeria.
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Chijioke John Ajaelu
  • Chijioke John Ajaelu
  • Department of Chemistry and Industrial Chemistry, Bowen University, Iwo, Osun State, Nigeria.
  • Google Scholar
Esther Oremeiyi Faboro
  • Esther Oremeiyi Faboro
  • Department of Chemistry and Industrial Chemistry, Bowen University, Iwo, Osun State, Nigeria.
  • Google Scholar


  •  Received: 17 September 2020
  •  Accepted: 05 January 2021
  •  Published: 31 March 2021

Abstract

This study examined the adsorption of copper onto raw Globimetula oreophila leaves. The adsorbent surface nature was examined using scanning electron microscopy and Fourier transform infrared spectroscopy. Adsorption parameters such as the –log10[H+], point of zero charge, initial metal concentration, mass of biomass and contact time were determined. Copper adsorption decreased gradually with pH. The point of zero charge (PZC) obtained was 4.5. The percentage adsorption capacity increased from 97.6 to 99.3% as the initial amount of copper rose from 20 to 100 mg/L. Temkin isotherm gave the best fit (R2=0.99) in describing the adsorption equilibrium process. Contact time effect resulted in an equilibrium attained in 15 min due to the initial rapid increase in adsorption. Kinetic data were excellently fitted to the pseudo-second order model. Thermodynamic studies affirmed a spontaneous and endothermic adsorption process. The activation energy and the energy of adsorption obtained affirmed that the adsorption process was chemisorption. G. oreophila is a recommendable adsorbent for the remediation of copper contaminated soil.

 

Key words: Globimetula oreophila, kinetics, adsorption, isotherm, copper.