Synthesis and Characterization of Hydroxyapatite/Titania Composite and its Application on Photocatalytic Degradation of Remazol Red B Textile Dye under UV Irradiation

Abstract

This research was conducted to synthesize and characterize hydroxyapatite-titania (HA/TiO 2 ) composites and test their photocatalytic degradation activity on the remazol red RB textile dye. The chemical precipitation method was utilized to produce hydroxyapatite (HA) based on the conversion of calcium carbonate presented in sea mussel shells into calcium oxide with a calcination temperature of 1000°C for 2 hours and then followed by the addition of phosphorous acid at pH medium of 11 and sintered at 700°C to obtain an HA crystal. The HA/TiO 2 composite at variation weight of HA and TiO 2 ratio were prepared with hydrothermal technique and characterized by the FTIR spectroscopy, X-ray diffraction, and scanning electron with energy dispersive X-ray spectroscopy. A total of 250 mL of 50 mg/L Remazol red RB dye solution was photocatalytically removed using a HA/TiO 2 composite irradiated with 25 Watt UV light and using the adsorption method. Characterization results using FTIR, XRD, and SEM-EDX show that the synthesized hydroxyapatite (HA) has a degree of crystallinity of 68% with a Ca/P ratio of 1.66. The highest degradation efficiency of 250 mL of remazol red RB with a concentration of 50 mg/L was achieved at 94.22% in 2 hours of contact time by a photocatalysis treatment employing the HA/TiO 2 composite at a ratio of 1:1 in comparison to only 92.23% removal by the HA adsorption process.