Efficient separation of actinides is critical for the proper treatment and disposal of nuclear waste. Affected by solution environmental factors such as hydrolysis, actinides feature complex and variable speciation, which poses considerable challenges to the formulation of wastewater treatment and environmental remediation strategies. It is therefore necessary to gain a comprehensive understanding of the formation process, compositional structure and chemical behavior of actinide cluster aggregates. This project intends to investigate the exploration of new actinide speciation and separation applications based on structurally adaptive pseudorotaxane ligands. Starting with molecular design, a series of pseudorotaxane ligands with dynamically tunable structures will be synthesized by introducing various types of supramolecular interactions. The as-prepared pseudorotaxane ligands will then be utilized for the selective recognition and capture of cluster intermediates generated from actinide hydrolysis. X-ray diffraction, nuclear magnetic resonance and other characterization techniques will be employed to determine the species composition and coordination chemical properties of actinide clusters, revealing the mechanism by which supramolecular interaction types affect the dynamic molecular effects of pseudorotaxanes. Finally, based on the findings of coordination and recognition between pseudorotaxane ligands and actinide clusters, a novel separation method for actinides relying on cluster aggregates will be developed. Successful implementation of this project will pioneer new approaches for studying the hydrolysis of actinyl ions represented by uranium, and provide references for the application of supramolecular chemistry in the recognition and separation of molecular ions.

actinides; hydrolytic clusters; supramolecular interactions; pseudorotaxane ligands; coordination recognition and separation