Hierarchical Ni–Al Layered Double Hydroxide In Situ Anchored onto Polyethylenimine-Functionalized Fibers for Efficient U(VI) Capture

Extracting U(VI) from seawater is highly appealing as a new energy source with the growing shortage of land supplies. However, the very low concentration of U(VI) and the enormous volume of seawater for throughput pose a considerable challenge for practical application. Herein, we report on an organic–inorganic hybrid adsorbent material with layered double hydroxides (LDHs) anchored onto polyacrylonitrile fibers (PANs) covalently modified with polyethylenimine (PEI) with facile implementation. In addition, the adsorption performance of PAN–PEI/LDH via column sorption under continuous flow was assessed with simulated seawater. From our results, the PAN–PEI/LDH adsorbent exhibits a high adsorption capacity of 553.96 mg g –1 at mg L –1 level, and the maximum amount of U(VI) uptake from seawater is 0.283 mg g –1 under contact with simulated seawater for 42 days; it offers promising potential for PAN–PEI/LDH as an adsorbent in the extraction of U(VI) from seawater.