The regeneration of the hard-alloy carbide wastes is an important scientific/engineering problem, the solution of which is directed to increasing the level of recycling of the refractory rate metals (W, Co, Nb, Ta and so on); as a rule these alloys do not exceed 25-30 percent of the production volume, even in the economically highly developed countries (1). The annual use of the carbide alloys in Japan is approx 3150 t in terms of WC, while the scale of the reprocessing of the wastes is only 848 tonnes (2). A similar situations is typical for the other countries that produce and use the hard alloys (USA, China, Russia) (3-5).In considerable degree this situation is associated with the significant drawbacks of the known technological schemes for regenerating the hard-alloy wastes, limiting the profitability of their factory processing. One of the techniques widely used to strip the carbide wastes is fusion of the wastes with sodium nitrate, then the melt is processes by the hydrometallurgical methods (1,6). However this approach has serious drawbacks that significantly limit its application in present-day conditions: the ecological contaminations associated with the forming of the oxides of nitrogen, the multi-operation nature of the process, the very high losses of the metals in the processes, and the inevitability of contamination of the commercial product in the combined processing of the wastes of differing composition.
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