Separation and purification of tantalum from plumbomicrolite of amazonite deposit in Kola Peninsula by acid leaching and solvent extraction

A plumbomicrolite concentrate (PMC) was decomposed with the mixture of HF and H2SO4, HF and HCl, HF and HNO3 acids. Optimal conditions ensuring high recovery of tantalum and niobium (99%) into solution, and radionuclides into insoluble residue were determined. Fluoride-sulfuric acid and fluoride-nitric acid schemes were proposed for PMC processing with an extraction separation of tantalum form niobium, lead and impurities and production of high-purity tantalum compounds.

采用氢氟酸（HF）与硫酸（H₂SO₄）、氢氟酸与盐酸（HCl）、氢氟酸与硝酸（HNO₃）的混合酸体系对铅微晶石精矿（plumbomicrolite concentrate，PMC）进行分解，确定了可实现钽与铌回收率达99%并转入溶液、放射性核素留存于不溶残渣中的最优工艺条件；针对该精矿的处理，提出了氟-硫酸体系与氟-硝酸体系两种工艺方案，通过萃取分离钽与铌、铅及杂质，可制备得到高纯钽化合物。