Removal of Cadmium Ions from Aqueous Solution by Nanostructured Carbonated Fluorapatite Bearing Siliceous Phosphorite

摘要

A middle grade siliceous phosphorite from Yunnan province was selected to treat Cd~(2+) bearing aqueous solutions.The siliceous phosphorite was tested by X-ray fluorescence spectrometer, X-ray diffraction, infrared spectrometer and scanning electron microscopy. The results present that the valuable mineral is nanostructured carbonated fluorapatite and the major gangue mineral is quartz. The amount ofCd~(2+) sorbed by the siliceous phosphorite tends to increase with the increase of initial pH or the initial Cd~(2+) concentration of the simulated waste water. The reaction process of Cd~(2+) removal from aqueous solutions is highly fitted with the pseudo-second order kinetic model. The results indicate that nanostructured carbonated fluorapatite bearing siliceous phosphorite can effectively immobilize aqueous Cd~(2+).