African Journal of
Environmental Science and Technology

  • Abbreviation: Afr. J. Environ. Sci. Technol.
  • Language: English
  • ISSN: 1996-0786
  • DOI: 10.5897/AJEST
  • Start Year: 2007
  • Published Articles: 1071

Full Length Research Paper

Adsorption studies of phosphate ions on alginate-calcium carbonate composite beads

Zahid Mahmood
  • Zahid Mahmood
  • Minerals Processing Research Centre, PCSIR Laboratories Complex, Lahore-54600, Pakistan
  • Google Scholar
Saqib Nasir
  • Saqib Nasir
  • Minerals Processing Research Centre, PCSIR Laboratories Complex, Lahore-54600, Pakistan
  • Google Scholar
Nadia Jamil
  • Nadia Jamil
  • College of Earth and Environmental Sciences, University of the Punjab, Lahore-54590, Pakistan
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Asma Sheikh
  • Asma Sheikh
  • Minerals Processing Research Centre, PCSIR Laboratories Complex, Lahore-54600, Pakistan
  • Google Scholar
Adnan Akram
  • Adnan Akram
  • Minerals Processing Research Centre, PCSIR Laboratories Complex, Lahore-54600, Pakistan
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  •  Received: 31 August 2014
  •  Accepted: 21 January 2015
  •  Published: 30 March 2015

Abstract

Alginate-calcium carbonate composite beads was prepared by the sol-gel method and characterized by Fourier transform infra-red spectroscopy (FT-IR) and scanning electron microscope (SEM) instruments. Adsorption potential of phosphate ions have been studied on laboratory scale. The effects of contact time, adsorbent dosage, initial analyte concentration, pH and agitation speed were optimized at 298.15 K (25°C) in a single ion system. The adsorption process was in accordance with Freundlich model and pseudo second order kinetics. Thermodynamic parameters like ∆G°, ∆H° and ∆S° have also been determined. Negative values of ∆G establish the favorability of the process. Values of ∆H and ∆S indicate that the process was endothermic and during the adsorption of phosphate ions (PO4-3), less randomness takes place at the adsorbent-adsorbate interface. 
 
Key words: Alginate-calcium carbonate, composite beads, phosphate ion adsorption.