Proof-of-Concept Study on PFAS Removal from Water Using Metal-Loaded Biochar Derived from Waste Palm Leaves in Qatar

Per- and polyfluoroalkyl substances (PFAS) are persistent contaminants in water that are not effectively removed by standard treatment methods. This poses a significant challenge for sustainable water management in Qatar, where water security primarily depends on desalination and treated groundwater. This research investigates the use of metal-loaded biochar derived from locally sourced palm leaves (Phoenix dactylifera) as an economical, regionally available adsorbent for removing PFAS from water systems.

The process involves converting palm leaf biomass into biochar through controlled pyrolysis, followed by thermal activation and metal loading to enhance surface reactivity and adsorption capacity. The resulting material underwent comprehensive characterization, including X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and carbon-hydrogen-nitrogen-sulfur (CHNS) elemental analysis. These techniques confirmed the successful formation of biochar, thermal modification, and metal incorporation.

Batch adsorption experiments were conducted under controlled conditions using PFAS-spiked water samples, and liquid chromatography–tandem mass spectrometry (LC/MS) was used to measure the significant and consistent reductions in PFAS concentrations after treatment with the metal-loaded biochar. Compared to unmodified biochar, the enhanced performance was attributed to an increased specific surface area and improved porosity, along with the presence of metal-active sites that facilitated PFAS uptake through electrostatic attraction, hydrophobic interactions, and ligand-exchange mechanisms.

Overall, this study demonstrates the technical feasibility of transforming an abundant byproduct of Qatar's date palm industry into advanced functional materials for addressing emerging contaminants. This approach supports circular-economy goals and aligns with Qatar's National Environment and Climate Change Strategy, while providing a scalable and regionally adaptable solution for PFAS management in arid and semi-arid water systems.