Abstract:Hydroxyapatite (HAP) was prepared by coprecipitation method under different pH values, Ca/P molar ratio and aging time, and the optimum conditions for preparing HAP were obtained according to its adsorption properties for Mn2+. On this basis, the adsorption properties of HAP prepared at the optimum conditions on Mn2+ under the influence of solution pH value, HAP dosage, reaction time and initial concentration of Mn2+ were studied by static tests. The adsorption mechanism was analyzed by combining adsorption kinetics model and adsorption isothermal model. The results show that the optimum preparation conditions of HAP include pH=10, molar ratio Ca/P=1.67 and aging time of 24 h. When initial concentration of Mn2+ is 5 mg/L, pH value is 7, HAP dosage is 1 g/L, and reaction time is 360 min, HAP has the best adsorption effect on Mn2+, and its adsorption capacity and removal rate are 4.97 mg/g and 98.4% respectively. The adsorption of Mn2+ by HAP is more consistent with the Freundlich isotherm model and the quasi-second-order kinetic model, which the adsorption process is a monolayer chemisorption.