NIOBIUM RECOVERY FROM TITANIUM TETRACHLORIDE PRODUCTION BY-PRODUCTS

This article presents the results of a study on the processing of industrial by-products from titanium tetrachloride production for the purpose of niobium extraction. Three types of niobium-containing materials were studied: titanium chlorinator sludge, dust chamber sublimate, and molten slag from the dust-settling chamber with a salt bath. The chemical and phase compositions were investigated using SEM-EDS, XRF, and XRD methods. Niobium was found predominantly in the form of refractory oxides and complex phases. Thermodynamic modeling using HSC Chemistry confirmed the stability of niobium oxides and the possibility of chlorination to volatile chlorides in a reducing environment. Leaching experiments showed that traditional water and acid treatments (HCl, H₂SO₄) result in low niobium extraction rates (up to 26%), whereas HFcontaining solutions allow for recovery of up to 53%. Based on experimental and modeling data, optimal parameters for selective niobium extraction were established. The proposed approach enables efficient recovery of valuable rare elements and contributes to the reduction of environmental impact from titanium production residues.

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