Abstract:During the synthesis process to hydroxyapatite, an ultrasonic-assisted microwave hydrothermal method was used to prepare a weakly crystalline iron-modified hydroxyapatite (Fe-HAP) by adding a certain proportion of FeCl3.6H2O. Fe-HAP has the removal performance for Pb2+, Cd2+ and As(Ⅴ). An X-ray diffraction, X-ray photoelectron spectroscopy, specific surface area analysis were employed to investigate the structural properties of Fe-HAP. The effects of different synthesis processes on the removal of Pb2+, Cd2+ and As(Ⅴ) were studied. An orthogonal experiments were used to evaluate the various factors that affect the adsorption performance of the material. For As(Ⅴ) removal, the optimal synthesis condition of Fe-HAP is 40% of iron doping content, pH 9.5, 15 min ultrasonic-microwave time. The maximum saturated adsorption capacity of As(Ⅴ) is 49.4 mg/g. Regarding the removal of Pb2+ and Cd2+, the optimal synthesis condition of Fe-HAP is 20% of iron content, pH 11, 200W ultrasonic power, 15min ultrasonic-microwave time. The maximum saturated adsorption capacities of Pb2+, Cd2+ are 1000mg/g and 339.3 mg/g. The results of orthogonal experiments showed that the molar ratio of Fe/(Fe+Ca) is the most important factor for Pb2+ and Cd2+ removal, while synthetic pH is crucial factor for As(Ⅴ) removal. The removal of Pb2+ , Cd2+ and As(Ⅴ) by Fe-HAP contribute to the adsorption and precipitation.