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Journals / Journal of the Turkish Chemical Society Section B: Chemical Engineering / 2026 / Volume: 2026

Alkaline Pretreatment of Chamaerops humilis L. Fibers: Effect of NaOH Concentration on Composition and Structure

Hayat Sami(Moulay ismail university)0009-0004-1437-4131
Oumayma Oulidi(Moulay ismail university)0000-0001-6596-7157
Mostapha Karaoui(Moulay ismail university)0000-0002-7331-4823
Ibtissam Elaaraj(moulay ismail)0000-0002-4765-6328
Asmae Nakkabi(moulay ismail)0000-0002-9845-243X
Mohammed Alami(moulay ismail)0000-0000-0000-0002
Noureddine El Moualij(moulay ismail)0000-0000-0000-0005
Pages
—
Publication Date
2026-05-09
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AI Summary & Key Takeaways

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⚡ TL;DR(Too Long; Didn't Read)

XRD results indicated increased crystallinity with moderate alkali concentrations, while SEM images showed enhanced surface roughness due to removal of non-cellulosic materials.

📌 3 Key Takeaways

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Objective & Hypothesis:In this study, natural fibers extracted from the Moroccan doum plant (Chamaerops humilis L.) were subjected to alkaline treatment using sodium hydroxide (NaOH) solutions at varying concentrations (0%, 6%, 8%, 12%, and 20% w/w) for 24 hours.
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Key Findings & Data:XRD results indicated increased crystallinity with moderate alkali concentrations, while SEM images showed enhanced surface roughness due to removal of non-cellulosic materials.
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Conclusion & Impact:These findings highlight an optimal NaOH concentration range for improving fiber–matrix compatibility while avoiding damage to the cellulose backbone.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Chamaerops humilis L · Alkaline treatment · FT-IR

Abstract

In this study, natural fibers extracted from the Moroccan doum plant (Chamaerops humilis L.) were subjected to alkaline treatment using sodium hydroxide (NaOH) solutions at varying concentrations (0%, 6%, 8%, 12%, and 20% w/w) for 24 hours. The objective was to evaluate the impact of alkaline concentration on the structural, chemical, and morphological characteristics of the fibers for potential reinforcement in polymer matrices. Alkaline treatment was selected for its simplicity, cost-efficiency, and environmentally benign nature. The treated fibers were characterized using Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). FT-IR analysis revealed progressive removal of hemicellulose and lignin, evidenced by the reduction of characteristic absorption bands. XRD results indicated increased crystallinity with moderate alkali concentrations, while SEM images showed enhanced surface roughness due to removal of non-cellulosic materials. However, at higher concentrations (≥ 12%), over-treatment led to fiber surface degradation and partial structural collapse. These findings highlight an optimal NaOH concentration range for improving fiber–matrix compatibility while avoiding damage to the cellulose backbone.

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Cite This Article

Sami, H., Oulidi, O., Karaoui, M., Elaaraj, I., Nakkabi, A., Alami, M., Moualij, N. E. (2026). Alkaline Pretreatment of Chamaerops humilis L. Fibers: Effect of NaOH Concentration on Composition and Structure. Journal of the Turkish Chemical Society Section B: Chemical Engineering, Volume: 2026. https://doi.org/10.58692/jotcsb.1803337

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