Recovery of Niobium, Titanium and Yttrium from Poly-mineralized Concentrate of Gabal El- Aurf Pegmatitic Rocks, Central Eastern Desert, Egypt

The present study focuses on the processing of a poly-mineralized concentrate attained from a physical beneficiation of process applied to high grade pegmatitic rock sample of Gabal El- Aurf area. The concentrate contains significant amounts of niobium (Nb), tantalum (Ta), titanium (Ti) and rare earth elements (REE) plus yttrium (Y) assaying 19.5, 2.5, 14.2 and 21.2%, respectively. The economic minerals within the concentrate include euxenite, tant-euxenite, samrsakite, allanite, and anatase.

The processing procedures involve an alkaline potassium hydroxide fusion applied to the poly- concentrate. This is followed by water leaching to extract dissolved Nb and Ta as water-soluble potassium niobate and tantalate. The remaining hydrous cake undergoes leaching process using 1.2M oxalic acid for selective extraction of titanium as soluble potassium-oxalatotitanat. The residue obtained after oxalic acid leaching is then utilized for the recovery of insoluble REE- oxalate. Subsequently, yttrium is individually separated from a nitrate solution using 2M tri-butyl phosphate (TBP) at pH 1.5. The final proposed technical flowsheet outlines the recovery of pure oxides of Nb–Ta, Ti, and Y.