Electrochemical processing of W – Re alloy wastes in alkaline electrolytes under the influence of alternating current

Absence of industrially mastered rhenium deposits in Russia leads to the necessity of recycling of this massif from its production wastes and involving various types of secondary rhenium-containing raw materials in production using efficient extraction process flowsheets. In connection with this, the process of electrochemical dissolution of wastes from tungsten-rhenium alloys VR-5 (ВР-5) and VR-20 (ВР-20) (containing 5 and 20% (wt.) of rhenium, respectively) was researched in Na2CO3 and NaOH solutions using alternating sinusoidal electric current. Anodic dissolution has big velocity, current output reaches 97%, and component transfer in electrolyte is proportional to their content in alloy. The carried out investigations showed the principal possibility of rather easy electrochemical regeneration of tungsten-rhenium alloys with obtaining the solutions, containing valuable components. Electrolytes are useful for further processing by the known technological methods with application of pure KReO4 as rhenium-containing intermediate product. Conversion of KReO4 into the most wide-spread rhenium precursors (NH4ReO4 or HReO4) has no technological difficulties. It can be carried out by the liquidus extraction methods, ion-exchange sorption or electrodialysis. The carried out investigations offered the principal process flowsheet of tungsten-rhenium alloy waste processing with rhenium extraction as KReO4.