Study of Kinetics of Chemically Activated Carbon Produced from Palm Kernel Shell

Abstract

Palm kernel shells (PKS), waste product of oil mill industrials, were used to produce activated carbon by chemically activating with ZnCl2. The shells were carbonized at temperature ranging from 500°C to 800°C, for an hour and activated with 10%, 20% and 30% concentration of ZnCl2. The effect of carbonization temperature and concentration of ZnCl2 were studied. Batch adsorption studies on adsorption of Cu2+ by ‘PKS 700°C activated’, ‘PKS 700°C non activated’ and ‘PKS 500°C activated’ were also carried out. Langmuir and Freundlich isotherms fit the data from the experiment. The adsorption capacities of the samples were studied. Results of single component kinetic studies on the samples revealed that about 93% of the metal ion removal occurred in the first 30 minutes. The adsorption rate constant for the samples at adsorption temperature of 15°C, 25°C and 50°C were ‘0.0462, 0.0654, 0.125’, ‘0.0343, 0.0395, 0.070’ and ‘0.281, 0.0313, 0.054’ (min-1) respectively. The result shows that PKS 700°C activated had the highest adsorption capacity. The entropy and energy of activation were also determined and it was found out that adsorption is an exothermic and a reversible process. The reaction was found to be first order reaction with respect to ZnCl2.