Leaching of radioactive and rare-earth elements from pegmatite steenstrupine and from rocks of the Lovozero massif
Ermolaeva V.N., , Mikhailova A.V., Kogarko L.N.
Due to high contents of Th, U and REE alkaline rocks of Lovozero massif may be considered as a potential object for the leaching of the radioactive and rare elements.
In alkaline rocks of Lovozero massif we find new important form of concentration of Th, U è REE – it is minerals of steenstrupine-(Ce) – thorosteenstrupine series Na0-5Ca1-3(REE,Th)6(Mn,Fe,Al,Ti)4-5[Si6O18]2[(Si,P)O4]6(OH,F,O)X·nH2O. They are widely spread also in pegmatite bodies of the massif, they contain up to 29.14 mass. % of Th and up to 2.56 mass. % of U (Chukanova et al., 2004). In this regard we make a number of experiences by leaching of Th, U è REE from pegmatite steenstrupine and steenstrupine-containing magmatic rocks of the Lovozero massif by several reagents: 1N solutions of HCl, NaOH, Na2CO3, 2% solutions of (NH4)2C2O4 (ammonium oxalate) è C10H14O8N2Na2·2H2O (trilon B). After leaching solutions was analyzed by ICP MS method in the case of steenstrupine and NAA in the case of steenstrupine-containing rocks. Use for sorption concentration of components of solutions after leaching from steenstrupine-containing rocks polymeric hydrogels on the basis of the polyacrylamide was feature of our approach. This hydrogels are capable to hold large amounts of water (up to 104 sm2 on 1 g of polymer) and the substances dissolved in it (Savvin et al., 2009).
Our experiments shown, that most degree of leaching both petrogenic and rare elements from the minerals of steenstrupine-(Ce) – thorosteenstrupine series is observed for HCl and trilon B. Results of leaching from the rocks show, that Th from lujavrite is leached most effective by HCl, (NH4)C2O4 and C10H14O8N2Na2·2H2O solutions, U – Na(OH), and REE – HCl. For foyaite samples HCl, (NH4)C2O4 and C10H14O8N2Na2 solutions as a whole are most effective for radioactive and rare earth elements extraction. So we can conclude that the obtained data testify to efficiency of elements concentration on hydrogel and their INAA-determination.
Compositional features and
genesis of steenstrupine from
Savvin S.B., Kolesov G.M., Mikhailova A.V.
Water systems: concentrating concentrating