| Abstrakt: |
Phoenix dactylifera waste is a burden on farm owners, the state as well as the environment, if it is not treated appropriately. Thus, to reduce this burden and its impact on the society, we have valorised these wastes by their transformation in the form of adsorbents. This study presents a comparative study of phenol removal from water solution by natural Phoenix dactylifera fiber (NF) and Phoenix dactylifera fiber chemically activated with H3PO4 (ACF). The sorbents were characterized by Brunauer–Emmett–Teller (BET) isotherms, Barrett–Joyner–Halenda, Fourier-transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. NF and ACF showed a predominantly mesoporous structure with a BET surface area of 1.108 and 269.543 m2/g, respectively. Batch adsorption experiments were carried out to study the effect of pH, contact time, adsorbent mass, initial phenol concentration and temperature on phenol adsorption. Under an optimum pH value of 6.0, the maximum adsorption capacities based on experimental results was 3.45 mg/g (with equilibrium time of 120 min) for NF, while it was 9.62 mg/g (with equilibrium time of 210 min). The adsorption isotherm of phenol on NF and ACF fits the Freundlich model well. The kinetic study showed that the adsorption data follow a pseudo-second-order kinetic model. The thermodynamic parameters namely Gibbs free energy (ΔG°), standard enthalpy (ΔH°) and standard entropy (ΔS°) were also calculated. The results show that adsorption of phenol onto NF and ACF was non spontaneous and exothermic. [ABSTRACT FROM AUTHOR] |
