Bio-assembled MgO-coated tea waste biochar efficiently decontaminates phosphate from water and kitchen waste fermentation liquid

Chuchu Feng, Lan Zhang, Xiu Zhang, Jingyu Li, Yimeng Li, Yaru Peng, Yuan Luo, Ronghua Li, Bin Gao, Mohamed A. Hamouda, Ken Smith, Esmat F. Ali, Sang Soo Lee, Zengqiang Zhang, Jörg Rinklebe, Sabry M. Shaheen

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)


Crystal morphology of metal oxides in engineered metal-biochar composites governs the removal of phosphorus (P) from aqueous solutions. Up to our best knowledge, preparation of bio-assembled MgO-coated biochar and its application for the removal of P from solutions and kitchen waste fermentation liquids have not yet been studied. Therefore, in this study, a needle-like MgO particle coated tea waste biochar composite (MTC) was prepared through a novel biological assembly and template elimination process. The produced MTC was used as an adsorbent for removing P from a synthetic solution and real kitchen waste fermentation liquid. The maximum P sorption capacities of the MTC, deduced from the Langmuir model, were 58.80 mg g−1 from the solution at pH 7 and 192.8 mg g−1 from the fermentation liquid at pH 9. The increase of ionic strength (0–0.1 mol L−1 NaNO3) reduced P removal efficiency from 98.53% to 93.01% in the synthetic solution but had no significant impact on P removal from the fermentation liquid. Precipitation of MgHPO4 and Mg(H2PO4)2 (76.5%), ligand exchange (18.0%), and electrostatic attraction (5.5%) were the potential mechanisms for P sorption from the synthetic solution, while struvite formation (57.6%) and ligand exchange (42.2%) governed the sorption of P from the kitchen waste fermentation liquid. Compared to previously reported MgO-biochar composites, MTC had a lower P sorption capacity in phosphate solution but a higher P sorption capacity in fermentation liquid. Therefore, the studied MTC could be used as an effective candidate for the removal of P from aqueous environments, and especially from the fermentation liquids. In the future, it will be necessary to systematically compare the performance of metal-biochar composites with different metal oxide crystal morphology for P removal from different types of wastewater. Graphical Abstract: [Figure not available: see fulltext.]

Original languageEnglish
Article number22
Issue number1
Publication statusPublished - Dec 2023


  • Biowaste-derived biochar
  • Dephosphorization
  • Fermentation liquid
  • MgO carbon composite
  • Phosphorus sorption

ASJC Scopus subject areas

  • Biomaterials
  • Environmental Science (miscellaneous)
  • Soil Science
  • Pollution


Dive into the research topics of 'Bio-assembled MgO-coated tea waste biochar efficiently decontaminates phosphate from water and kitchen waste fermentation liquid'. Together they form a unique fingerprint.

Cite this