A Comparative Study of Phenol Removal by Pisum-sativum Peels Biochars Derived at Different Pyrolysis Temperatures: Isotherm, Kinetic and Thermodynamic Modelling

摘要

Pea peels were used for the preparation of biochar at different temperatures (250 degrees C: PP250, 500 degrees C: PP500 and 750 degrees C: PP750) using slow pyrolysis for 1 h and used for the phenol removal from an aqueous medium. Biochar samples were characterized by SEM, XRD and FT-IR. The phenol removal was examined as a function of pH, temperature, and NaCl and urea concentration. The optimum pH and temperature were found to be 6.0 and 25 degrees C respectively. Presence of NaCl and urea primarily affected the adsorption capacity of PP250 and slightly affected the adsorption potential of PP500 and PP750. The maximum biosorption capacity for the PP250, PP500 and PP750 were found to be 34.63, 46.70, and 60.10 mg/g respectively. The Langmuir isotherm and Pseudo-second order kinetic model best explained the adsorption. Thermodynamic parameters corroborated the physical and exothermic nature of adsorption. PP750 can preferably be used for phenol removal than PP500 and PP250.