Elektrokhimicheskaya pererabotka otkhodov tyazhelykh vol'framovykh splavov v rastvorakh karbonata ammoniya

Abstract

The electrochemical behavior of tungsten and the VNZHK alloy (wt. %: W 90; Ni 7.2; Fe 1.8; Co 1) in solutions of (0.5—1.5 M) ammonium carbonate was investigated by linear voltammetry in a potentiodynamic mode. An increase in the maximum anodic density of the oxidation current of tungsten and the VNZHK alloy was revealed with an increase in the ammonium carbonate concentration. The process of electrochemical dissolution of the VNZHK alloy waste in a 1.0 M solution of ammonium carbonate was investigated by galvanostatic electrolysis, as well as electrolysis under the action of a sinusoidal alternating current of industrial frequency. The advantage of alternating use of direct and alternating currents is justified. It has been established that during the processing of the VNZHK alloy waste under the alternating action of direct and alternating currents, the transition of tungsten from the alloy to an ammonium carbonate solution is accompanied by the concentration of the iron subgroupmetals in the microdisperse sludge of electrolysis. A basic technological scheme for the tungsten extraction from the heavy tungsten alloys waste with the production of ammonium paravolframate as the final product is proposed.