EXTRACTION OF LANTHANIDE CHLORIDES, NITRATES, AND PERCHLORATES BY METHYLENEBIS(DI-N-HEXYLPHOSPHINE OXIDE) AND RELATED EXTRACTANTS

The partition behavior of the lanthanides between aqueous hydrochloric, nitric and perchloric acid media and carbon tetrachloride or 1,2-dichlorobenzene solutions of methylenebls(dialkylphosphine oxides) is described in terms of the equilibrium constants for the various adducts. The lanthanide perchlorates form trisolvates with MHDPO, methylehebis(di-n-hexylphosphine oxide), where '3 is approximately 1010. A trisolvate is also indicated for the lanthanide nitrates, where the free MHDPO concentration is sufficiently large with '3 = 1.1 — 106. Lower solvates are also indicated for the nitrate system at lower free MHDPO concentrations and a disolvate appears to be the highest solvate formed with the lanthanide chlorides with '2 in the range 0.1 to 1. © 1969, American Chemical Society. All rights reserved.