Yttrium complexation with benzoic acid and tris(hydroxymethyl)aminomethane

Yttrium complexation in extraction systems with benzoic acid (BA) and tris(hydroxymethyl)aminomethane (THMAM) was studied. The growth of yttrium distribution ratios in this system is caused by the formation of different-ligand coordination compounds of yttrium with BA and THMAM. Quantum chemical calculations for the formation energy of different-ligand complex showed that the most stable complex forms when yttrium atom coordinates to two THMAM molecules via oxygen and nitrogen atoms and to one THMAM molecule via nitrogen atom. The complex is stable in both bidentate and monodentate coordination of the carboxyl groups of benzoic acid to yttrium atom. Obtained yttrium extracts were used for the synthesis of complex-oxide nanosized cathodophosphors by extraction-pyrolytic technique.