Uranium Extraction from Radioactive Wastewater by NH₂-MIL-125 Immobilized in a Double-Network Aerogel Microsphere

An environmentally friendly adsorbent for recovering nuclear energy source U(VI) from wastewater plays a crucial role in resource recovery and environmental preservation. In this work, a double-network aerogel adsorbent composite constructed from sodium alginate, poly(acrylic acid), and NH2-MIL-125 (NM@SA) was fabricated by a mild method, which was adopted to remove and concentrate U(VI) in the corresponding simulated wastewater samples. According to the results of adsorption kinetic and isotherm models, the adsorption of U(VI) on NM@SA was a monolayer chemisorption process. The maximum adsorption capacity of NM@SA for U(VI) calculated from the Langmuir model was 703.6 mg·g–1. In addition, the adsorbent maintained excellent adsorption capacity, recoverability, and reuse in large-scale operation. The same abilities can be demonstrated in real seawater environments. Finally, the potential adsorption mechanisms of U(VI) on NM@SA were discussed in conjunction with the experimental determination and characterization results. Overall, this study introduces an advantageous research approach for treating U(VI)-containing radioactive wastewater.