Production and characterization of porous calcium silicate ceramics by starch consolidation technique by using waste egg shells

In this thesis work, calcium silicate-based bioceramic materials were produced with starch consolidation technique using waste chicken eggshell and silica. The effect of the amount of silica used in the composition in the process of bioceramic synthesis from eggshell and kaolin reinforcement to the system on the phase composition achieved was investigated. Sintering studies were carried out by applying a 3°C/min sintering rate, between 1100-1300 °C and 2 hours. Sintering shrinkage % was calculated by measuring the size (diameter and thickness) of the samples before and after sintering. The phase composition of the samples was investigated using the x- ray diffraction method, microstructure development was investigated with a scanning electron microscope, and chemical structures were examined with Fourier Transform Infrared spectroscopy. It was determined that different phases were formed in the structure depending on the designed composition and applied sintering conditions. When the phase analysis results were examined, it was determined that calcium silicate or larnite phases were formed in each design, but depending on the conditions and composition, different phases such as wollastonite could also be formed in the structure. It was determined that only the dicalcium silicate phase was formed in the structure as a result of sintering the samples with the designed stoichiometric dicalcium silicate composition at 1250°C for 2 hours.