Kinetics and equilibrium adsorption study of lead(II) onto activated carbon prepared from coconut shell

M. Sekar, V. Sakthi, S. Rengaraj

Research output: Contribution to journalArticle

463 Citations (Scopus)

Abstract

Removal of lead from aqueous solutions by adsorption onto coconut-shell carbon was investigated. Batch adsorption experiments were performed to find out the effective lead removal at different metal ion concentrations. Adsorption of Pb 2+ ion was strongly affected by pH. The coconut-shell carbon (CSC) exhibited the highest lead adsorption capacity at pH 4.5. Isotherms for the adsorption of lead on CSC were developed and the equilibrium data fitted well to the Langmuir, Freundlich, and Tempkin isotherm models. At pH 4.5, the maximum lead adsorption capacity of CSC estimated with the Langmuir model was 26.50 mg g -1 adsorbent. Energy of activation (Ea) and thermodynamic parameters such as ΔG, ΔH, and ΔS were evaluated by applying the Arrhenius and van't Hoff equations. The thermodynamics of Pb(II) on CSC indicates the spontaneous and endothermic nature of adsorption. Quantitative desorption of Pb(II) from CSC was found to be 75% which facilitates the sorption of metal by ion exchange.

Original languageEnglish
Pages (from-to)307-313
Number of pages7
JournalJournal of Colloid and Interface Science
Volume279
Issue number2
DOIs
Publication statusPublished - Nov 15 2004

    Fingerprint

Keywords

  • Adsorption
  • Coconut-shell carbon
  • Isotherms
  • Kinetics
  • Lead
  • Thermodynamics and desorption

ASJC Scopus subject areas

  • Colloid and Surface Chemistry
  • Physical and Theoretical Chemistry
  • Surfaces and Interfaces

Cite this