The Quality Study of Hydroxyapatite (HAp)-TiO2 Composites from Pokea (Batissa violacea var. celebensis) Shell Waste by Hydrothermal, Microwave and Precipitation Methods

Research on the quality study of hydroxyapatite (HAp)-TiO2 composites from Pokea (batissa violacea var. celebensis) clamshell waste by hydrothermal, microwave and precipitation methods have been successfully conducted. This study aims to determine the characteristics and quality of HAp-TiO composites2 synthesized from Pokea clam shell using three different methods, namely hydrothermal, microwave and precipitation. FTIR characterization showed the absorption of PO4-3 functional groups in the wave number range 567-1091 cm-1, -OH and -NH groups at wave numbers 3444-3448 cm-1, and Ti-O groups at 567-632 cm-1. XRD analysis revealed a diffraction pattern at 2θ = 26.67o, with crystal sizes of HAp-TiO2 material of 80.20 nm, 71.47 nm, and 73.28 nm for hydrothermal, microwave and precipitation methods, respectively. The mechanical properties showed that the highest compressive strength of the HAp-TiO2 composite was obtained in the hydrothermal method (6.07 MPa), followed by the precipitation method (5.19 MPa) and microwave (5.08 MPa). The material density test results for the hydrothermal, microwave and precipitation methods were recorded at 2.27 MPa, 2.12 MPa, and 1.73 MPa. The test results showed the highest value in the hydrothermal method of 24.24 MPa, while the microwave and precipitation methods produced hardness of 18.61 and 18.83 MPa, respectively. Digital optical microscope analysis showed the surface morphology of the material to be uniform, refined grains with pores. The results in this study indicate that the hydrothermal method produces composites with better mechanical quality and crystal structure than other methods.