Phenol adsorption onto high surface area activated carbon prepared from agriculture waste Fox nutshell by chemical activation with H3PO4: batch and fixed bed studies

Abstract

The aim of this study is the phenol adsorption onto produced high surface area activated carbon prepared from Fox nutshell with the H3PO4 activating agent in N2 atmosphere. The optimally activated carbon (FNAC) which had the highest surface area and pore volume was obtained by these conditions as follows: 3:2 impregnation ratio, 700 ºC carbonization temperature and 1 hour carbonization time. The optimally produced activated carbon resulted with a carbon content of 64.85% and a yield of 30.38%, while the surface area of 2636 m2 g-1, with the total pore volume of 1.53 cm3 g-1, microporosity of 86.27% and average pore diameter of 2.32 nm. Its adsorptive performance was tested by using phenol. The influence of system variables such as pH, temperature, adsorbent dosage, contact time, and initial concentration of phenol solution was systematically investigated. The adsorption kinetics, equilibrium, and thermodynamics of phenol adsorption were studied. Adsorption experimental results show that the prepared activated carbon exhibited high adsorption capacity of 83.21 mg g-1 to phenol uptake. In column experiments, the effects of bed height and flow rate on phenol adsorption were studied. The highest bed capacity of 75.64 mg/g was obtained using 100 mg/l initial phenol concentration, 4 cm bed height and 5 ml/min flow rate.