Towards experimental and theoretical understanding of the adsorption behavior of phenol on a new activated carbon prepared from oak wood

Although phenol is frequently used in various industrial applications, it is a very dangerous pollutant; thus, wastewater containing this pollutant must be properly treated before being released into the environment. In this sense, a new activated carbon (AC), prepared from Atlas oak, has been successfully used to remove phenol from aqueous solutions. The new material has been characterized by Scanning Electron Microscopy with Energy Dispersive X-ray spectroscopy (SEM/EDX), X-Ray Diffraction (XRD), and Fourier-Transform Infrared spectroscopy (FTIR); its textural properties have been also examined by nitrogen adsorption/desorption measurements. By using H3PO4 acid as an activator, the activated carbon's ability to adsorb phenol was assessed under various conditions. Indeed, the adsorption process follows the pseudo-second-order kinetics, and the isotherm data were best fitted with the Langmuir model. Thereby, the highest adsorption capacity, which has a value of 250 mg g‐−1, was achieved for an equilibration time of 2 h, an initial concentration of 10−2 mol L−1, an adsorbent mass of 100 mg, and a pH value of 4; this capacity exceeds that of other adsorbents. On the theoretical level, statistical physics modeling of the experimental data shows that the monolayer with two energy sites model (M2) was found to be the best model to describe the phenol adsorption phenomenon. Indeed, steric parameters indicate that the phenol molecules tend to be vertically adsorbed to the surface of the new material. The thermodynamic data reveal that phenol adsorption is physical, spontaneous, and endothermic in nature as well as it depends on electrostatic interactions, hydrogen bonds, and potential interactions. Finally, the present work may open the way for the development of new low-cost, effective, and natural adsorbents in order to remove pollutants from wastewater. •Activated oak charcoal was valorized as phenol adsorbents from an aqueous solution.•Structural and textural properties have been assessed using several technics.•The kinetics and thermodynamics of phenol adsorption on activated carbon were studied.•Statistical physics modeling was applied to describe the phenol adsorption phenomenon.