Integrated physicochemical and structural characterization of date palm pit–derived biochar produced by slow pyrolysis

Year 2026, Volume: 15 Issue: 2 , 242 - 252 , 01.04.2026

Amjed Salata , Galina Borisova Maria Maleva

https://doi.org/10.18393/ejss.1885879

https://izlik.org/JA26HG26XN

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

Supporting Institution

Ministry of Science and Higher Education of the Russian Federation

Project Number

FEUZ-2024-0011

Thanks

The work was supported and funded by the Ministry of Science and Higher Education of the Russian Federation (project FEUZ-2024-0011). The authors would like to express their sincere gratitude to Ural Federal University, Institute of Natural Sciences and Mathematics, Department of Experimental Biology and Biotechnology, for providing the research facilities, academic guidance, and technical support essential for the successful completion of this work.

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