Characteristics of Ammonia Adsorption on Various Sizes of Calcium Carbonate Microparticles from Chicken Eggshell Waste

The purpose of this study was to synthesize calcium carbonate from chicken eggshell waste for ammonia adsorption. Experiments were done by heating eggshell waste. The heated materials were then milled and sieved to get calcium carbonate microparticles with a specific size (500, 1000, and 2000 mu m). The particles were then characterized using a microscope and infrared spectroscopy (FTIR) to identify particle morphology and functional groups, respectively. The prepared particles were then used for ammonia adsorption, tested, and compared with ten isotherm models (such as Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Jovanovic, Halseys, Harkin -Jura, Flory -Huggins, Fowler -Guggenheim, and Hill-Deboer) to identify the adsorption mechanism. The pseudo -second -order kinetic model was suggested for describing the adsorption process that occurs to form a complex multilayer layer between the adsorbent and the adsorbate. This result was supported by the investigation of the adsorption isotherm model, which found that all particle sizes have a pattern where a multilayer layer is formed due to the distribution of pores. Layer formation during the adsorption process involves physisorption and chemisorption with spontaneous and endothermic systems. The particle size confirms the difference in ability as indicated by the adsorption capacity value. The smaller the particle size, the greater the maximum capacity because it has a large surface area. On the other hand, the smaller particle size impacts the obtainment of the greater maximum capacity because of its large surface area. This study shows that the use of eggshell waste has the potential. This study shows that the use of eggshell waste has the potential to be used as an adsorbent and supports the Sustainable Development Goals (SDGs) program.