Electrochemical recovery of rhenium from W–Re alloys in the form of perrhenic acid: I. Fundamentals of the process

Resumo

Linear voltammetry is used to study the anodic behavior of a VR20 alloy in sodium hydroxide solutions, and the possibility of high-rate dc electrochemical dissolution of this alloy is shown. Experimental dependences of the rate of alloy dissolution and the anode current efficiency on the anode current density are determined, and the electric power consumed for alloy dissolution under optimum conditions is determined in large-scale tests. Potassium perrhenate is removed from the formed electrolyte as an intermediate product to form perrhenic acid. The main characteristics of the electrodialysis conversion of the synthesized potassium perrhenate into perrhenic acid with a concentration of 591 g/L electrolyte are determined. A technological scheme is proposed for the recovery of rhenium from the wastes of a W–Re alloy in the form of perrhenic acid.