Eggshell derived CaO-Portland cement antibacterial composites

Abstract

Eggshells have been reported to generate huge tons of waste globally owing to their increasing consumption. Apart from its dietary benefits, the use of eggshell waste as a catalyst, filler in soil-cement bricks, dental cement, bone filler, etc. has been widely reported. This study uses a heat-treated eggshell by extracting calcium oxide, CaO, to prepare cement antibacterial composites. Thermogravimetric Analysis (TGA), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS or EDX), and Fourier transform infrared (FTIR) characterization techniques were used to understand the changes in the eggshell upon heat-treatment. Pure CaO obtained by heating eggshell at 900 °C was also examined for antibacterial activity against E.Coli and was found to be highly effective. CaO derived from eggshell was replaced with 5%, 10%, and 15% of cement weight of mortar and studied for antibacterial activity. It was observed that with increasing CaO content, the capacity of the specimen to kill bacteria increased on the surface. This usage of heat-treated eggshell in mortar can be a potential antibacterial composite. The novelty of this work highlights the use of heat-treated eggshell in preparation of antibacterial composites.

Keywords

• Eggshell
• Mortar
• Antibacterial activity
• Cao
• E. Coli