Amidoxime Functionalized Hydroxyapatite Composites Separate The Uranium(Vi) From Aqueous Solution

Amidoxime functionalized hydroxyapatite (HAP) composites were prepared and characterized by means of Fourier-transform infrared spectroscopy, scanning electron microscopy and X-ray powder diffraction. The adsorption characteristics of the adsorbent on uranyl ions were studied, and the effects of solid-liquid ratio, pH value, ionic strength, temperature, equilibrium time and other factors on the adsorption process were investigated. Under the optimum conditions, the adsorption capacity of the modified HAP material can reach 889.7 mg/g. The adsorption thermodynamics and kinetics data show that the adsorption of U(VI) by amidoxime (AO) functionalized hydroxyapatite is a spontaneous exothermic process, and the adsorption equilibrium can be reached within 30 min, which is in line with the Langmuir isothermal adsorption model. AO-co-HAP has a very good selectivity for U(VI). The desorption rate of U(VI) can reach 97.88% in 0.15 M acid solution. Compared with the traditional separation method, this adsorbent has a wider range of raw materials and a lower cost of waste liquid treatment, so it has an excellent practical application value.