A novel polyalcohol-coated hydroxyapatite for the fast adsorption of organic dyes

Surface-modified hydroxyapatite (HA) nanocomposites have been synthesized from D-fructose-1,6-phosphate trisodium salt octahydrate (DFP) via a simple and green hydrothermal process. Comprehensive X-ray powder diffraction (XRD), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), Thermal gravimetrical analysis (TGA), Fourier transform infrared (FT-IR) and solid state nuclear magnetic resonance (SSNMR) characterizations revealed that the HA nanocomposite adopt a rod-like core/shell morphology in which the inorganic HA core is covered with an organic shell of polyalcohol species. The HA nanocomposite exhibits a large surface area of 203.18 m 2 /g, and enhanced adsorption capacities of organic dyes such as Methyl orange (MO) and Congo red (CR). Remarkably, the adsorption processes were particularly fast in which the equilibriums are reached within minutes. The adsorption kinetics can be well described by a pseudo-second-order kinetic model. These experimental results demonstrated that such HA nanocomposites are promising adsorbents for the efficient removal of organic dyes from water.