Elaboration of a new Activated Carbon derived from the Crown of Oak (ACOW) to removal the toxic Iodine: Kinetic, Isotherms modelling and Thermodynamics Study

ABSTRACT

The current study aims to develop a new adsorbent material using oak crown and explore its effectiveness in removing I₂ ions through a series of batch experiments. ACOW was characterised by zero charge (pHpzc) and FTIR spectroscopy. The impact of the initial I₂ concentration (20-100 mg/L), temperature (25-55 °C), pH (2-14), adsorbent dosage (2-10 g/L), Stirring speed (100-900 rpm), particle size (100-2000μm) and contact time (0-30 min) on I₂ adsorption was examined. The adsorption kinetic obeys the pseudo-second order model with a determination coefficient (R²) equal to 0.999. Adsorption follows the Langmuir equation well, with the best fit to the experimental data at equilibrium. A q_max value (= 103.606 mg/g) at 25°C and 120.773 mg/g at 55°C were eliminated under the optimised conditions, indicating homogeneous adsorption on the surface of the adsorbent. The thermodynamic parameters gave a negative free energy ΔG^o (-3.445 to -5.629 kJ/mol), a positive enthalpy ΔH^o (18.406 kJ/mol) and an activation energy E_a (= 22.599 kJ/mol), thus confirming the spontaneous and endothermic nature of adsorption of iodine on ACOW. The positive entropy ΔS^o (0.0733 kJ/mol K) show increased randomness of the solid-liquid interface during the adsorption.

KEYWORDS:

• Crown of oak
• iodine
• isotherm
• removal
• thermodynamic
• modelling

Acknowledgements

The authors gratefully acknowledge support from the University M'hamedBougara of Boumerdes (UMBB), Laboratory of Applied Chemistry and Materials (LabCAM), Faculty of Sciences and Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry (USTHB) Algeria. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Disclosure statement

No potential conflict of interest was reported by the authors.

Ethical statement

Our study did not require an ethical board approval because it did not contain human or animal trials.

Additional information

Notes on contributors

Tounsia Aksil

Dr. Tounsia AKSIL, Research Professor at UMBB, Field of expertise: Water Treatment and Food Technology. Applied Chemistry and Materials Laboratory (UMBB).

Moussa Abbas

Pr. Dr. Moussa ABBAS, Lecturer Researcher at UMBB, Responsible for the Research team on the recovery of materials in Water decontamination. Laboratory of Applied Chemistry and Materials (UMBB).

Mohamed Trari

Pr. Dr. Mohamed TRARI, Research Lecturer at USTHB, Director of the Laboratory of Storage and Valorization of Renewable Energies.