Unconventional extraction of uranium from seawater through microenvironment-specific conjugated microporous poly(aniline)s

The sustainability of uranium-based nuclear energy relies on the development of quick and effective uranium adsorbents. Herein, we propose a facile post-synthetic technique by grafting amino-functional groups onto the fluorenone-functionalized conjugated microporous poly(aniline)s (CMPs) network to acquire a novel class of N decorated polymers for uranium capture. By leveraging the abundant N sites and microenvironment-containing molecular structure, CMPA-F-BDA showcases excellent UO22+ adsorption performance with fast adsorption kinetic with initial adsorption rate up to 43.78 mg g−1 min−1, Langmuir adsorption capacity of 443 mg g−1 and exceptional adsorption selectivity of Kd = 1.3 × 107 mL g−1 even in the serious presence of competitive cations. Additionally, CMPA-F-BDA could treat up to 18.5 L g−1 of low-concentration uranium solution (1 mg L−1) and actual seawater, removing 87.9% of uranium from 10 L of seawater, and has excellent reusability. This study demonstrates the bright future of CMPs for the extraction of low-concentration uranium.