Characterizations of Calcium Oxide from Calcined Eggshell Waste

Abstract

The eggs are not only a good source of nutrients but their shells are rich in various minerals of which CaCO3 is the most prominent. Egg shell contains about 90% CaCO3 of the total weight. The interest in clean technology has attracted the use of eggshell waste as a focus of research. The objective of this work is to extract calcium oxide (CaO) from calcium carbonate (CaCO3) available in chicken eggshells. CaO is white in colour possessing high porosity with narrow particle size distribution. CaO have very high percentage of ceramic yield. This CaO can be used as precursor for synthesis of calcium phosphate that can be further used in biomaterial synthesis. The uncalcined eggshell waste (ESW) and calcined ESW powders were characterized by using X-ray diffraction (XRD), Scanning electron microscope (SEM) and Fourier transform infra-red (FTIR) analyses. The calcination temperatures were varied from 700 oC to 1100 °C. XRD and FTIR results suggested that CaCO3 is converted into calcium oxide at 900 °C and SEM micrographs also compliment these results. The calcination method can be used to extract calcium oxide from ESW being eco-friendly as well as low cost.