Abstract

Biochar, a carbon-rich material produced via biomass pyrolysis, has attracted growing attention due to its diverse physicochemical properties and potential relevance in soil-related and environmental applications. In this study, biochar was produced from date palm (Phoenix dactylifera L.) pit residues, an abundant agro-industrial by-product, through slow pyrolysis at temperatures of 350 °C. The resulting material was systematically characterized to evaluate its physicochemical and structural attributes using proximate analysis, pH and cation exchange capacity (CEC) measurements, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDX), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Brunauer–Emmett–Teller (BET) surface area analysis. The characterization results revealed that the produced biochar had a high yield of 75%, a low ash content (1.22%), and an acidic pH of 4.46. The biochar also exhibited a carbon-rich composition with a fixed carbon content of 27.3%, a measurable BET surface area of 18.22 m² g⁻¹, and a cation exchange capacity of 20.45 (cmol(+) kg⁻¹) These properties reflect the structural and chemical features of the biochar generated under the applied pyrolysis conditions. While no soil or biological performance was evaluated in this study, the measured physicochemical characteristics suggest potential relevance for future soil-based or environmental assessments. Overall, this work demonstrates the valorization of date palm pit residues into biochar with well-defined physicochemical and structural properties, contributing to waste management strategies and circular bioeconomy approaches. Further studies are recommended to assess the performance of this material under specific application conditions.

Keywords: Date palm pit biochar, slow pyrolysis, physicochemical properties, porous structure, cation exchange capacity, agro-industrial residue.

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