Valorization of salt post-modified poultry manure biochars for phosphorus recovery from aqueous solutions: investigations on adsorption properties and involved mechanism

Samar Hadroug, Salah Jellali, Ahmed Amine Azzaz, Marzena Kwapinska, Helmi Hamdi, James J. Leahy, Mejdi Jeguirim*, Witold Kwapinski

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

14 Citations (Scopus)


In this research work, raw poultry manure biochar (RPM-B) was post-modified by two metal salts and then evaluated for P recovery from aqueous solutions in batch mode. The modified biochar characterization showed that RPM-B impregnation with aluminum and manganese salts led to a significant improvement of their surface properties through the pH-zero charge reduction as well as the specific surface areas and the functional group contents increase. Phosphorus recovery tests indicated that the post-treated biochar with AlCl3 (RPM-B-Al) and with KMnO4 (RPM-B-Mn) exhibited relatively high recovery efficiencies with Langmuir’s adsorption capacities of 23.5 and 8.4 mg g−1, respectively. Kinetics and isothermal data modeling, as well as the in-depth analytical characterization of the post-modified biochars before and after adsorption, indicates that P recovery occurs homogeneously on monolayer surfaces through mainly anion exchange, precipitation, and electrostatic interactions. On the other hand, P desorption efficiency increases with the desorbing solution pH values. The best P desorption yields were observed for an initial pH of 9.0 to 78% and 80% for RPM-B-Al-P and RPM-B-Mn-P, respectively. All these results suggest that RPM-B-Al and RPM-B-Mn could be considered promising materials for phosphorus recovery from wastewaters with a possible reuse in agriculture as potential soil amendments.

Original languageEnglish
Pages (from-to)4333-4348
Number of pages16
JournalBiomass Conversion and Biorefinery
Issue number10
Publication statusPublished - Nov 26 2021


  • Desorption
  • Metal salts
  • Phosphorus recovery
  • Post-treatment
  • Poultry manure biochar

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment

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