Main content area

A facile synthesis of hydroxyapatite for effective removal strontium ion

Xia, Xu, Shen, Juan, Cao, Fang, Wang, Congjun, Tang, Mi, Zhang, Qingyuan, Wei, Shasha
Journal of hazardous materials 2019 v.368 pp. 326-335
Fourier transform infrared spectroscopy, X-ray diffraction, adsorbents, adsorption, desorption, effluents, endothermy, hydroxyapatite, leaching, models, nanosheets, nitrogen, pH, particle size, raw materials, scanning electron microscopy, strontium, surface area, temperature, thermodynamics, thermogravimetry, transmission electron microscopy
Hydroxyapatite (HA) with perforated porous structure was successfully synthesized using shell powder as the raw material by double interfacial diffusion method. The structure of obtained products was examined by X-ray diffraction, Fourier transform infrared spectrograph, field-emission scanning electron microscopy, transmission electron microscopy, particle size, thermogravimetry and nitrogen adsorption–desorption analysis etc. Results indicate that the perforated porous structure is composed of nanosheets and has high specific surface area (up to 188.5 m2 g–1). Thus, investigation of adsorbing Sr2+ in solution was further examined by discussing factors such as initial pH, ion strength, adsorbent dosage, contact time, initial Sr2+ concentration and temperature. The kinetics and equilibrium adsorption data followed the nonlinear pseudo-second-order kinetic and Liu isotherm models. The maximum removal (%) was up to 98.94% at 313.15 K, and the adsorption process of Sr2+ was endothermic, feasible, and spontaneous in nature as studied via thermodynamic analysis (ΔG° < 0, ΔH° > 0, and ΔS° > 0). A possible adsorption mechanism was proposed. Meanwhile, leaching and desorption experiments was used to evaluate recycling capacity. All the outcomes effectively reveal that the synthesized HA shows great potential in removing Sr2+ from nuclear effluents.