The vibrational spectra of the halides and complex halides of the Group IIBelements. Part II. A Raman spectroscopic study of the systems HgX2–LiX (X = Cl, Br) in aqueous and tri-n-butyl phosphate solutions

Abstract

The Raman spectra of aqueous solutions containing varying proportions of mercuric halide and lithium halide, and of the tri-n-butyl phosphate (TBP) extracts of these aqueous solutions are reported. Although the HgX3– anion is not observed in aqueous solution, it seems to be the most stable species in the tri-n-butyl phosphate extracts. The extraction of mercury(II) from aqueous lithium halide solutions into tri-n-butyl phosphate thus differs from the previously reported extraction from concentrated halogen acids. Expressions are derived for the distribution ratio of mercury(II) for the individual extraction of HgX42– and HgX3–, and the dependence of the distribution ratios on the lithium ion, halide ion, and tri-n-butyl phosphate concentrations is verified experimentally.