Tantalum and hafnium are strategic metals widely used in the field of national defense industry. Tantalum hafnium resource in our country, although have some reserves, limited by factors such as grade, production cost and mining technology, the annual domestic tantalum hafnium far cannot meet the demand of domestic smelting, as a strategic reserve, metal tantalum hafnium imports are vulnerable to the international situation, the high temperature alloy waste contains considerable valuable metallic elements, if these valuable metallic elements can be recycled for the use and application of strategic metals have very important sense, contains a tantalum rich tungsten slag in the method of separation of tungsten tantalum, tantalum by sodium carbonate, sodium hydroxide and its contain rich after tungsten slag mixture after roasting and water immersion process to separate tungsten tantalum, separation effect is better, in addition, The conventional acid leaching processing and roasting - separation of the water treatment process of high temperature alloy scrap can be nickel, cobalt, tungsten, molybdenum and other metal recycling valuable metals, still have a certain amount of tantalum in the rest of the alloy slag and hafnium, most of these tantalum hafnium alloy slag down-cycled, caused the waste of resources and environmental pollution, if can recycle the tantalum hafnium, not only can make up for the external dependence of tantalum hafnium resource in our country, to protect our strategic needs, but also for our country to provide more tantalum hafnium reserves.
Oxygen atmosphere will under the condition of tantalum hafnium alloy slag roasting with sodium carbonate blend, roasting process, tantalum hafnium alloy slag of hafnium disulfide, hafnium nitride and hafnium oxide priority react with sodium carbonate generated hafnium acid sodium, the present invention by reasonable adjustment tantalum hafnium alloy slag ratio with the quality of the sodium carbonate and calcined temperature, control of tantalum hafnium with sodium carbonate reaction rate, make the hafnium generated at the same time only tiny amounts of acid sodium sulfide and tantalum, tantalum nitride tantalum pentoxide react with sodium carbonate formation of tantalum acid sodium, and mixed with sodium carbonate and tantalum hafnium alloy slag as raw materials for the roasting, to ensure that the generated after roasting calcined product not agglomeration, After being calcined product cooling will be put in sulfuric acid pickling, at this point, the concentrated sulfuric acid can react quickly and hafnium acid sodium, and the reaction rate of tantalum acid sodium slower, and sulfide tantalum, tantalum nitride and tantalum pentoxide almost no reaction takes place, the resulting solid liquid mixture enrichment of hafnium in liquid phase, the enrichment of tantalum in solid phase, the solid-liquid mixture adding deionized water in order to lower the viscosity of the mixture of solid and liquid, the filtered in the filtrate of tantalum and hafnium mass ratio is less than 5%, shows that a large number of hafnium exists in the filtrate, residue of hafnium and tantalum mass ratio is less than 2%, shows that a large number of tantalum exists in residue, so as to realize the separation of tantalum and hafnium, The method is easy to implement and the separation effect of tantalum and hafnium is good.
