Green synthesis of sulfonated conjugated microporous polyaniline/collagen fiber composites for efficient and sustainable seawater uranium extraction

The escalating demand for nuclear energy, coupled with the finite nature of terrestrial uranium resources, necessitates the exploration of sustainable seawater uranium extraction. Here, we report the rational design and facile synthesis of a novel composite adsorbent, SCMPA-2/CF, for efficient and biofouling-resistant seawater uranium extraction. This adsorbent integrates collagen fibers (CF), derived from leather waste, with sulfonated conjugated microporous poly(aniline)s (SCMPAs). The composite was fabricated via a Buchwald-Hartwig coupling reaction, grafting sulfonic acid-functionalized SCMPA-2 onto the hierarchical porous structure of CF. The inherent hierarchical porosity of CF significantly accelerates mass transfer, while its surface amino groups provide anchoring sites for the functional SCMPA-2 particles. The strategically incorporated −SO 3 - exhibit a synergistic effect, achieving high-capacity U(VI) adsorption through combined electrostatic attraction and chemical chelation. Furthermore, the conjugated microporous poly(aniline) structure imparts antibacterial properties, ensuring long-term performance. Adsorption experiments demonstrate remarkable performance: over 90% U(VI) uptake within 30 min, a Langmuir maximum adsorption capacity of 642 mg g −1 , exceptional U(VI) selectivity with a distribution coefficient ( K d ) of 5.67 × 10 6  mL g −1 , and a substantial capacity of 3.14 mg g −1 retained after two weeks of continuous sea trials. The composite also exhibited strong antibacterial activity, with over 91% inhibition rates against E. coli and S. aureus . Notably, the estimated production cost is as low as 1.10 USD·g −1 , attributed to the utilization of cost-effective waste biomass. This work establishes a green, high-performance, biofouling-resistant, and economically viable adsorbent for seawater uranium extraction, offering a promising avenue for developing nuclear energy resources from waste biomass.