Rare Metal Separation And Preconcentration Of Trace Niobium Tantalum Research

As the same group elements in the rare metals. Nb and Ta are usually associated in nature, they are so closed that It is difficult to separate them. The spectrophotometric determination of them is also interfered each other for the most wavelengths of them are so closed.There are several methods in the separation of Nb and Ta, But the resolve extraction is the most common method. The main extractant are Methylisobutyketone (MIBK), TBP, acetamide and Para-cotanol. Amoung the extractant, acetamide and Para-cotanol are our country's independent methods. Few other extractant are introduced.The separation and enrichment of Nb and Ta was researched in this paper. Solvent extraction method was applied to separate them, with the extractant of Cydohexanone and the NH4F was used as complex agent, through continuous explorations and experiments, at last the best experiment conditions were decided. We can get a satisfied result. Specify work as follows:1,Trace Nb and Trace Ta were separated each. The best condition of extraction has been found according to varying different conditions. When the acidity of extraction was 2.5mol/L^-1 and complex agent was 0.9g/20ml, the extraction rate of trace Ta can almost reached 100%.At the same time the about 8% trace Nb was extracted to the organic resolve. In the Re-extraction, the low acidity H₂SO₄ just Re-extract the Nb at first ,only the acidity was Diluted by plenty of water,then Ta can be Re-extracted. So change the concentration of the acid, the trace Nb and trace Ta can be separated accurately.2,The complex agent is also investigated. The different salts to the extraction rate are compared, the NH4F, with the use of 0.9g/20ml have the best result.3,The determination condition of trace Nb and trace Ta was studied. Including the stableness of the complexes, acidity of determination and so on. For the Shortages in the determination of trace Ta such as the short time stableness, Color lake, we tried and rectified the determination conditions again and again, finally surmounted these problems asmuch as possible and get a Satisfy result.4, the result of the mixture of trace Nb and Ta with different Proportion was resrearChed, and get a better Extraction technology at last.5,Discussed the Extraction Mechanisms, Reaction course and steps were researched and described clearly.