In-situ preparation of HPO42− intercalated NiFe layered double hydroxides for efficient U(VI) removal

The development of high-efficiency adsorption materials for efficient removal of U(VI) from nuclear wastewater has become a concern of environmental protection. LDHs, as adsorbent materials, lack functional groups, resulting in low adsorption performance. Herein, a novel and excellent radiation stable HPO42−-intercalated NiFe-LDH material (NiFe-LDH-P(x)) is synthesized by in-situ co-precipitation method. The effect of HPO42− content on the U(VI) performance of NiFe-LDH-P(x) is studied in detail. The results reveal that intercalation of HPO42− increases the interlayer spacing and specific surface area of NiFe-LDH, as well as the active sites between the interlayers. Therefore, NiFe-LDH-P(x) with moderate HPO42− content (10 %) can reach highest U(VI) adsorption capacity (350.88 mg·g−1). FTIR, SEM and XPS analyses educe that the efficient adsorption of uranium on NiFe-LDH-P(10 %) is mainly attributed to complexation, electrostatic attraction and ion exchange. In summary, NiFe-LDH-P(10 %) has great potential in removing uranium from wastewater, which provides a new idea for the synthesis of efficient adsorbents.