Biomaterials as promising biosorbents for efficient uranium extraction from seawater: A comprehensive review

Uranium in seawater could be one of the most persistent sources of energy that can meet the world's energy needs for nearly 1000 years; however, significant challenges remain in uranium extraction is the development of eco-friendly and cost-effective adsorbents without compromising the selectivity and adsorption capacity of the adsorbent. The inorganic adsorbents (including the trending amidoxime-functionalized materials) show good adsorption capacity; however, their slow adsorption kinetics, costly preparation methods, adverse effects on the marine environment, and biofouling susceptibility raise serious concerns about their large-scale applicability. On the other hand, biosorbents (including microbes and other bio-originated species) have the advantage of being environment-friendly, cost-effective, biofouling-resistant, and rapid kinetics. However, they still lag behind the amidoxime-based adsorbents in terms of their adsorption capacity. This review comprehensively summarizes the successive developments in uranium extraction from seawater using biosorbents. Furthermore, critically evaluate the recent developments in the application of biosorbents, preparation of biomaterials-originated biosorbents, and effects of influencing factors. The interaction mechanism of uranium with microbial biosorbents has been described in detail. Moreover, the potential of biosorbents in real seawater is also evaluated and described in detail. Based on the reported studies, various gaps are identified, and recommendations for improvement in adsorption capacity are made. Assessing the potential of these biomaterials in uranium recovery from real seawater highlights the immediate need for the scalable development of efficient biomaterial-based biosorbents. Despite facing multiple challenges, the ongoing research advancements in this realm indicate that biomaterials might play a critical role in uranium extraction from seawater in the future.