Scalable production of steam-activated wool carbon for highly efficient Cr(VI) adsorption

Heshmatian, Sara; Bakhshi, Hooman; Azizi, Shohreh; Madiba, Itani Given

doi:10.22126/arww.2026.13300.1455

Document Type : Research Paper

Authors

¹ Department of Engineering Sciences and Physics, Buein Zahra Technical University, Buein Zahra, Iran.

² UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, College of Graduate Studies, University of South Africa, Muckleneuk ridge, PO Box 392, Pretoria, South Africa.

https://doi.org/10.22126/arww.2026.13300.1455

Abstract

This study presents a sustainable approach for converting waste sheep wool into high-performance activated carbon for Cr(VI) removal from aqueous solutions. Chemical (NaOH) and steam activation routes were evaluated, and steam activation at 900 °C for 3 h in a rotary furnace produced the optimal material. The resulting carbon exhibited a high specific surface area (1807 m²/g), a pore volume of 1.002 cm³/g, and a well-developed micro-mesoporous structure. The optimized adsorbent achieved 99% removal of Cr(VI) from a 400 mg/L solution within 45 min. Physicochemical characterization (BET, SEM, XRD, Raman) and adsorption analysis (ICP-OES) confirmed the material’s suitability for adsorption processes. Equilibrium behavior was best described by the Freundlich isotherm (R² = 0.976), while the Langmuir model yielded a monolayer capacity of 147 mg/g. Kinetic data closely followed the pseudo-second-order model (R² = 0.999), suggesting adsorption dominated by electrostatic interactions and surface complexation under acidic conditions. These findings demonstrate that wool waste can be effectively valorized as a low-cost, scalable, and efficient adsorbent for Cr(VI) remediation.

Keywords

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Journal of Applied Research in Water and Wastewater

Scalable production of steam-activated wool carbon for highly efficient Cr(VI) adsorption

References

References

Articles in Press, Accepted Manuscript
Available Online from 22 April 2026

Scalable production of steam-activated wool carbon for highly efficient Cr(VI) adsorption

References

References

Articles in Press, Accepted Manuscript Available Online from 22 April 2026

Articles in Press, Accepted Manuscript
Available Online from 22 April 2026