Wp. Liao et al., Solvent extraction of cerium(IV) and fluorine(I) from sulphuric acid leaching of bastnasite by Cyanex 923, SOLVENT EXT, 19(2), 2001, pp. 243-259
The solvent extraction of cerium(IV) and fluorine(I) from simulated sulphur
ic acid leaching of bastnasite by Cyanex 923 was studied. The results showe
d that Cyanex 923 can extract not only Ce(IV) as Ce(HSO4)(2) (SO4) . (2)(Cy
anex 923) and F(I) as HF (Cyanex 923) respectively but them together. The e
xtraction mechanism of Ce(IV) together with F(I) can be related to the form
ation of Ce(HF)(HSO4)(2) (SO4) . (2)(Cyanex 923). It was also showed that b
oric acid in the leaching liquor which was added to chelate F(I) wasn't ext
racted alone by Cyanex 923 and didn't influence the Cerium(IV) extraction.
Boric acid can enhance the extraction of HF and came into organic phase in
form of (HF)(H3BO3)(Cyanex 923). Hydrofluoric acid was extracted from the b
astnasite leaching mainly together with Ce(lV). The results also showed tha
t temperature didn't affect the extraction process. IR spectra of purified
Cyanex 923 saturated with Ce(IV), HF and H3BO3 were discussed.