Posidonia oceanica (L.) fibers as a potential low-cost adsorbent for the removal and recovery of orthophosphate

Mohamed Ali Wahab*, Rafik Ben Hassine, Salah Jellali

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

30 Citations (Scopus)

Abstract

Adsorption efficiency of orthophosphate from aqueous solution onto Posidonia oceanica fibers (POF) as a raw, natural and abundant material was investigated and compared with other common natural materials. A series of batch tests were undertaken to assess the effect of the system variables, i.e. initial aqueous orthophosphate concentration, contact time, adsorbent dosage, pH and temperature. Results indicate that orthophosphate uptake increased with increasing initial orthophosphate concentration, temperature and adsorbent dosage and decreased with increasing pH values. The maximum adsorption capacity (Qm) determined from the Langmuir isotherm was calculated to be 7.45mgg-1 for the studied orthophosphates concentration range of 15-100mgL-1, pH 7; adsorbent dosage of 2gL-1 and temperature of 20±2°C. The adsorption data were very well described by the pseudo-second order model predicting a chemisorption process. The energy dispersive spectroscopy (EDS) and FTIR analysis before and after adsorption of orthophosphate onto POF showed that the main involved mechanisms are ligand exchange between orthophosphate and Cl-, SO42- and OH- and precipitation with calcium. In comparison with other natural adsorbents, raw POF could be considered as one of the most efficient natural materials for the removal of orthophosphate with the possibility of agronomic reuse.

Original languageEnglish
Pages (from-to)333-341
Number of pages9
JournalJournal of Hazardous Materials
Volume191
Issue number1-3
DOIs
Publication statusPublished - Jul 15 2011
Externally publishedYes

Keywords

  • Adsorption mechanisms
  • Modeling
  • Orthophosphate
  • POF
  • Removal

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Waste Management and Disposal
  • Pollution
  • Health, Toxicology and Mutagenesis

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