Phosphorus Removal from Aqueous Solution by Using Calcined Waste Chicken Eggshell: Kinetic and Isotherm Model

Excess phosphorus in water bodies stimulates algal growth and causes eutrophication. Eutrophication is one of the conditions that is a global problem in the environment and affects the quality of water in receiving water. Due to this matter, various wastewater treatment technologies have been developed to solve this problem; however, such technologies incur a high cost for their operation and maintenance. Hence, to seek the eco-friendly element in removing phosphorus from wastewater, this study used calcined waste chicken eggshell to remove phosphorus in an aqueous solution by using adsorbent with different particle sizes (0.075, 0.15, 0.30, 0.60, and 1.18 mm). The calcined waste chicken eggshells were calcined at 800 °C in a furnace and used as adsorbents. The phosphorus adsorption onto calcined waste chicken eggshell data from experiments was fitted to kinetic and isotherm models. Chicken eggshell is an eco-friendly material that has the potential as an adsorbent for removing phosphorus from an aqueous solution, where the highest removal is 98%. The best model for phosphorus removal is the pseudo-second-order (PSO) model, as it fits better with the data and has a high R2 of 0.9999. Calcined waste chicken eggshells have a multilayer adsorption property, making them a perfect adsorbent with high adsorption capabilities. The application of waste material to adsorb phosphorus from an aqueous solution shows the contribution of eco-friendly waste material use in real adsorption wastewater treatment technologies.