Activated carbon from sugarcane as an efficient adsorbent for phenol from petroleum refinery wastewater: Equilibrium, kinetic, and thermodynamic study

The adsorption method may be one of the environmentally friendly, economical, and effective techniques to remove phenol from wastewater using low-cost adsorbent activated carbon (AC). The effects of the initial concentration of phenol, temperature, and time of the adsorption on the phenol removal percent were studied. The maximum removal percentage of phenol was 63.73% of the initial 150 mg/l concentration obtained at 25 degrees C. Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich isotherm models have been applied to study the adsorption equilibrium. The results show that both Langmuir and Freundlich isotherms fitted the equilibrium data better with a high correlation coefficient (R-2) and a maximum adsorption capacity of 108.70 mg/g. Thorough fitting of adsorption kinetics data followed the pseudo-second-order model. Thermodynamic parameters were calculated in the temperature range of 25-50 degrees C. The results show that the adsorption process of phenol on AC is more favorable at low temperatures.