From eggshells biowaste to hydroxyapatite biomaterial

Abstract

In the present study a biowaste, in the form of chicken eggshells, is used for producing a biomaterial – hydroxyapatite by a conventional chemical precipitation method. Hydroxyapatite is a major component of human hard tissues, such as bones and teeth, which makes it a paradigmatic bioactive material. The first step in the synthesis of hydroxyapatite from eggshells is the transformation of their main component calcium carbonate into calcium oxide at 1000 °C. Afterwards, calcium oxide is hydrated in order to produce calcium hydroxide. Hydroxyapatite is then synthesized by the addition of the phosphoric acid. The phase composition of the eggshells is examined by the powder X‐ray diffraction. The surface morphology of the sintered product is determined by the scanning electron microscope equipped with the energy dispersive spectrometer. Powder X‐ray diffraction and scanning electron microscope analyses confirmed hydroxyapatite as the main phase of the final product. The reuse of chicken eggshells reduces the amount of biowaste, as well as the need for the biowaste management. This investigation shows that the eggshells can be a useful raw material for the synthesis of valuable biomaterials.

Synthesis and characterizations of natural limestone-derived nano-hydroxyapatite (HAp): a comparison study of different metals doped HAps on antibacterial activity

“…[6][7][8] The raw materials for producing hydroxyapatite can also be obtained from natural sources. Some previous studies examined hydroxyapatite manufacturing using natural calcium sources such as clamshell 9 and eggshell, 10 but their availability is limited. Therefore, the synthesis of HAp by utilizing earth-abundant sources is critical.…”

Pathways for Sustainable Utilization of Waste Chicken Eggshell

“…Effective production of hydroxyapatite [91] For example, CaCO 3 extracted from WCES was demonstrated to be a suitable coating agent to prevent corrosion and protect welded carbon steel joints. Bakar et al [85] adopted electrophoretic deposition for the coating of carbon steel with CaCO 3 derived from WCES.…”

Effect of Silica Addition on Mechanical Properties of Eggshell-Derived Hydroxyapatite

“…An eggshell, which accounts for about 11% of the egg's weight, is almost always disposed of as solid waste. The main element is calcium carbonate (95-97 wt%) with a minor amount of calcium phosphate, magnesium carbonate, organic, strontium, sodium, iron, potassium, and chlorine (Witoon, 2011;Curkovic et al, 2017). The high calcium content in chicken eggshells is the potential to be used as HAp material.…”

“…Later, HAp was modified with SiO2 at various concentrations with the coprecipitation method. This method is a simple, inexpensive, and high success (Curkovic et al, 2017). The resulting HAp and HAp/SiO2 were characterized using XRD, FTIR, and SEM-EDS.…”