Phosphazenes as Collective Extractants of Rare-Earth Elements

The extraction ability of some linear phosphazenes with respect to rare-earth elements (REEs) in a nitrate medium is studied. Some possible mechanisms of interaction between phosphazenes of different types and REEs at various acidities are discussed. It has been established that imido- and amidophosphazenes are very strong extractants of REEs within a broad range of nitric acid concentrations in the aqueous phase. It has been shown that phosphazenes can be efficient collective extractants of REEs.