Hierarchically structured layered-double-hydroxides derived by ZIF-67 for uranium recovery from simulated seawater.

Under the background of increasing and sustainable development of nuclear industry, it is significant to develop materials with high adsorption capacity and high selectivity of uranium as adsorbents. In this work, novel Mg-Co layered-double-hydroxide (LDH) with hierarchical structure was synthesized successfully via self-sacrifice template by ZIF-67. X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller surface area measurement (BET) and X-ray photoelectron spectroscopy (XPS) characterization were conducted, which confirmed the specifically hollow structured material possesses high surface area and abundant mesopores that makes uranium ions diffuse into it more easily. In typical batch adsorption experiments, varieties of parameters were investigated in details. In addition, adsorption of trace concentration of uranium (ppb level) in simulated seawater was also studied. The results showed as-prepared Mg-Co LDHs are promising adsorbents for extraction of uranium from simulated seawater.