Adsorption Isotherm, Kinetic, and Removal Efficiency Mechanism of Leachate Using Coconut Shell Activated Carbon and Peat Soil as Composite Adsorbent

The adsorption method is the most widely used technique for the reduction of different types of pollutants from an aqueous solution. Nowadays, in comparison to the commercial adsorbent, researchers are currently discovering economically cheap, require less processing, and are abundantly available in nature. The present study aimed to determine the reduction percentage of COD and ammoniacal nitrogen (NH3-N) by using coconut shell activated carbon (CSAC) and peat soil (PS) as an economically composite adsorbent as well as partly reducing the amount of CSAC. The method of determining the optimum condition of the composite was conducted by using static batch techniques. The optimum reduction conditions were achieved at 200-rpm rotational speed, 120-min rotational time, and pH 7. The optimum dosage ratio condition of CSAC:PS was achieved at 2.0:2.0 for the reduction percentage of COD and NH3-N. The best reduction percentage of COD and NH3-N were 79% and 70% respectively. The coefficient of determination values indicates that the Langmuir model for COD and NH3-N was in accordance with the experimental data for the elimination of contaminants investigated with 0.9982 and 0.9885, respectively. The coefficient of determination values indicates that pseudo-second order better fitted the equilibrium data over the entire concentration range studied compared to the pseudo-first-order kinetic model. The coefficient of determination for pseudo-second order was generally in the range of 0.9965 for COD and 0.9260 for NH3-N, respectively. This shows that the utilization of PS as a low-cost adsorbent as well as reduces the use of commercial adsorbent.