Preparation Of Tantalum

Metal tantalum powder can be obtained by metal thermal reduction (sodium thermal reduction) method. In the inert atmosphere with sodium metal reduction of potassium fluorotantalate: K2TaF7 + 5Na → Ta + 5NaF + 2KF. reaction in a stainless steel tank, the temperature is heated to 900 ° C, the reduction reaction is rapidly completed. This method of tantalum powder, irregular particle shape, fine particle size, suitable for the production of tantalum capacitors. Metal tantalum powder can also be produced by molten salt electrolysis: potassium fluorotantalate, potassium fluoride and potassium chloride mixture of molten salt as the electrolyte to tantalum pentoxide (Ta2O5) dissolved in it, electrolysis at 750 ℃, the purity of tantalum powder can be obtained for 99.8 ~ 99.9%.

②Tantalum metal can also be obtained by reducing Ta2O5 with carbon heat. Reduction is generally carried out in two steps: first of all, a certain ratio of Ta2O5 and carbon mixture in the hydrogen atmosphere at 1800 ~ 2000 ℃ made of tantalum carbide (TaC), and then TaC and Ta2O5 according to a certain ratio made of a mixture of vacuum reduction into tantalum metal. Tantalum metal can also be produced by thermal decomposition or hydrogen reduction of tantalum chloride. Dense tantalum metal can be prepared by vacuum arc, electron beam, plasma beam melting or powder metallurgy. High purity tantalum single crystals are produced by crucible-free electron beam area melting.