Calcium carbonate from chicken eggshells as adsorbents

Further research is needed to try to utilize calcium carbonate from chicken eggshells as an adsorbent. The use of chicken eggshells as adsorbent is expected to minimize the amount of waste generation and reduce environmental pollution. This research aims to utilize chicken eggshells as adsorbent. Eggshell powder was activated with 0.1 M HCl solution for 48 hours, then heated in an oven at 150°C for 30 minutes which aims to enlarge pores, increase surface area, increase volume and create new pores that will increase adsorption power. The adsorbent obtained was characterized using XRD, SEM-EDS, BET and BJH. Based on XRD data, it can be seen that the activated adsorbent contains calcium carbonate (CaCO3) which shows a phase with β-calcite symmetry. SEM data shows that the adsorbent particles are almost spherical in shape and some form an aggregate and there is an empty space. EDS analysis shows the concentration of calcium, carbon and oxygen are 27.05; 15.75 and 56.60% respectively. The results of BET analysis showed that the adsorbent obtained included type V, mesoporous category and type H3, the presence of nonrigid aggregate in the form of plates that have slit-shaped pores. The results of BJH analysis showed that the most dominant pore sizes were pores with diameter of 33.3 and 36.3 Å.