Advances in Porous Materials for Transuranic Element Separation

Nuclear energy, recognized as an efficient and stable power source, is poised to play an increasingly significant role in the global energy mix.The reprocessing of spent nuclear fuel is crucial in assessing whether nuclear energy can be deemed a sustainable form of energy.Among the various technologies involved, partitioning-transmutation technology not only reduces the long-term hazards associated with radioactive waste but also mitigates the environmental risks linked to the treatment of nuclear waste.The transuranic elements in high-level liquid waste (HLLW) possess relatively high toxicity and long half-lives.Therefore, the effective separation of transuranic elements from HLLW is a necessary condition and a key technology for separation-transmutation.Among the methods for the separation of actinides, solvent extraction has been widely applied due to its simplicity and low cost.However, this method also presents several challenges, such as the use of toxic or flammable solvents, the formation of emulsions, and the generation of large amounts of secondary organic hazardous waste.In contrast, solid-phase adsorption does not require organic solvents, thereby reducing the volume of solvents and the risk of secondary pollution.Moreover, the adsorption process can be conducted at ambient temperature and pressure, making it simple, low-cost, environmentally friendly, and regenerable.These advantages have contributed to its increasing popularity and research interest in recent years.However, the harsh conditions in HLLW present significant challenges in the development of solid-phase adsorbents.Despite many obstacles, advancements in solid-phase adsorbent materials for transuranic element separation have demonstrated considerable potential within the nuclear energy sector.This article provides a comprehensive analysis of the benefits, challenges, and prospective applications of solid-phase adsorbents.It offers a systematic review of research progress in various solid adsorbents, including inorganic porous materials, carbon-based porous materials, polymer resins, metal-organic frameworks (MOFs), and covalent organic frameworks (COFs), specifically in the context of transuranic element separation.The review investigates their strengths in terms of adsorption performance, selectivity, stability, and regenerability.Additionally, it highlights research challenges such as the complexity of preparation, economic viability, and the scalability of production processes.This thorough analysis is instrumental in the development of more efficient and eco-friendly transuranic element adsorbent materials and in facilitating their integration into practical nuclear energy