THE SCAVENGING OF URANYL FROM PHOSPHATE-CONTAINING MEDIA

This review discusses ligands which have been shown to form stable ura nyl complexes and to be selective for the UO22+ ion, with a view to th e recovery of U from phosphate-containing media. The most potent urano philes were shown to be relatively rigid macrocycles with a quasi-plan ar arrangement of five or six ligating groups. Hence, water soluble an d lipophilic calix[n]arenes (n = 5 or 6) have been named ''super-urano philes'' due to their remarkable uranyl selectivity and the extremely stable nature of their uranyl complexes.