High-efficiency adsorptive removal of U(VI) on magnetic mesoporous carbon/Sr-doped hydroxyapatite composites

Using a co-impregnation technique, Sr-doped hydroxyapatite (HAP-Sr) loaded in magnetic mesoporous carbon (MMC) was successfully prepared. Extensive characterization was performed on MMC, HAP-Sr, and the composite (MMC/HAP-Sr) to determine their properties. In addition, their U(VI) adsorption capacities were thoroughly investigated. The key factors influencing U(VI) adsorption were investigated. In accordance with the results, the equilibrium of MMC/HAP-Sr on U(VI) was reached within 10 min. In addition, the substance's theoretical saturation capacity was 1229.9 mg·g−1. XRD and XPS tests showed the sorption of U(VI) by MMC/HAP-Sr is mainly via precipitation and complexation with hydroxyl (-OH) on the surface. Thus, MMC/HAP-Sr is an excellent adsorbent for the treatment of radioactive wastewater containing U(VI).