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Converting date pits into biochar for the remediation of contaminated soil: A sustainable approach

Authors

  • Nabiha Aloui Email ORCID Department of Environmental and Aquaculture Sciences, University Kasdi Merbah, Ouargla 30000, Algeria; Process Engineering Laboratory, Ouargla 30000, Algeria

DOI:

https://doi.org/10.30564/re.v8i6.117279

Received:4 August 2026 |Revised:28 September 2026 |Accepted:6 October 2026 |Published Online:5 November 2026

Abstract

Oil waste severely affects date production and quality in the Ouargla region, as it disrupts the fragile oasis ecosystem. The coexistence of oil extraction and date cultivation causes soil and water pollution, which directly affects the metabolism of the date palm. Dates have been part of the daily human diet for thousands of years and are an essential component of the diet of Saharan populations. Date palm residues are abundant in many arid regions, presenting both an environmental challenge and an opportunity for sustainable resource management. This study valorizes date palm residues by slow pyrolysis at 600 °C in order to produce biochar suitable for the remediation of soils. Composition is fundamental to the concept of biochar as a means of C sequestration. In recent years, there has been considerable support for biochar use as a soil amendment to help mitigate climate  change  through  increased  C  storage  in  soils  and  reductions  in  net  carbon  dioxide  (CO2) emissions. The biochar is also known to have a high BET surface area, which is suitable to be used as an adsorption media. Thus, it can be a treatment agent for many pollutants such as polycyclic hydrocarbons heavy metals. The date palm residues we used in our study were the date kernels of the "Ghars" variety. Comprising 75.64% organic carbon, 0.16 % phosphorus, 0.65% potassium, 0.73 % magnesium and 0.19 % nitrogen. Scanning electron microscopy analysis of the biochar revealed that the high surface porosity of the product provided better attachment sites for microorganisms, which accelerated the degradation of hydrocarbons. The results of the analysis of hydrocarbons by GC/MS showed a marked reduction in the concentration of toxic compounds after treatment, which testifies to the effectiveness of the biochar treatment in decomposing heavy and complex compounds into lighter and more stable compounds, although some require longer degradation periods, demonstrating the effectiveness of biochar..

Keywords:

Oasis Ecosystem, Biochar, Treatment, Polycyclic Aromatic Hydrocarbons, Sustainable Development

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