Removal of fluoride from water by NiAl layered double hydroxide prepared by solvothermal method

Limin Wang and Danfeng He

Abstract

NiAl layered hydrotalcite was prepared by solvothermal method and the adsorption performance of F- in water was studied. According to the experimental results of single factors, heat treatment can increase the adsorption performance of the samples, but the higher roasting temperature can cause hydrotalcite layered structure destroyed, in this study, optimal calcination temperature is 150℃. As-prepared absorbent was calcinated at 150℃, various conditions such as initial fluorine ion concentration, adsorbent dosage, solution pH value, interfering ion survived together, adsorption temperature and adsorption time etc, were investigated. The sample was characterised by XRD and TEM, and the adsorption kinetics and adsorption isotherms were also analyzed. The adsorption equilibrium was achieved within 24 h on the adsorption reaction of fluoride ion in water. Adsorption isotherms fitted the Freundlich model. The adsorption kinetic fitted well the second-order dynamics model.