Eggshell derived calcium oxide – Synthesis and characterization

Chicken eggs are the most important cooking ingredient with rich protein and calcium. It can be consumed by all humans and the eggshells are disposed as a waste material to the environment. These waste materials are disposed directly in the environment without any pre-treatment which creates environmental pollution by its microbial action. Nowadays, the researchers are converting these waste materials into valuable biomaterials. More than 2.2 million people worldwide undergo bone transplantation each and every year. Surgery needs to repair large critical-size bone defects accidents, traumas, diseases. Hydroxyapatite is a biomaterial that is similar to the mineral component of the mammalian bones and it can also be used to replace the damaged bones as well as a coating material on various implant which enhance the bone growth of prosthetic implants in orthopedic, dental and maxillofacial reconstruction applications. The present investigation is to synthesize the CaO from the waste eggshells with different calcinations temperature from 400° C – 900° C via solid state reaction method. The resulting CaO is employed as the primary source for the production of HAp biomaterial; it is environmentally friendly and also increases the life span of the host. The synthesized CaO is characterized by FTIR, XRD and Thermogravimetric and differential thermal analysis. The Fourier transform infrared spectroscopy, X-ray diffraction results revealed that the phase transformation starts at 700°C and CaO formed at 900° C. TG-DTA analysis indicated that the calcium oxide is formed at 829° C during the decomposition of calcium carbonate. The less weight loss is observed from the TGA analysis and it could be used as precursor material for the production of bioceramic materials like HAp for biomedical applications.