From forest waste to functional adsorbent: NaOH-activated pine needle biochar for Rhodamine B remediation
Bhavana V P, Neelaambhigai MAYILSWAMY, Balasubramanian KANDASUBRAMANIAN, Rutuja Vasant SALUNKE
Abstract. This study explores NaOH-activated pine needle biochar (NaOH-PNB) for RhB removal from wastewater. Pine needles were pyrolyzed at 500°C, treated with 2 M NaOH, and re-pyrolyzed at 800°C to improve surface properties. The material showed a mesoporous structure suitable for adsorption. Maximum removal was achieved in 5 h, with PSO kinetics and a capacity of 4.08mg.g-1. The process was spontaneous and endothermic, driven by electrostatic interactions and hydrogen bonding. The adsorbent was reusable for up to 3 cycles using ethanol. NaOH-PNB showed better performance than other bio-adsorbents, supporting sustainable wastewater treatment.
Keywords
Pine Needle, NaOH-Activated Pine Needle Biochar, Rhodamine B Dye, Adsorption Kinetics, Adsorption Isotherms, Thermodynamics, Regeneration Studies
Published online 5/10/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Bhavana V P, Neelaambhigai MAYILSWAMY, Balasubramanian KANDASUBRAMANIAN, Rutuja Vasant SALUNKE, From forest waste to functional adsorbent: NaOH-activated pine needle biochar for Rhodamine B remediation, Materials Research Proceedings, Vol. 65, pp 35-40, 2026
DOI: https://doi.org/10.21741/9781644904138-6
The article was published as article 6 of the book Processing and Characterization of Materials
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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