Process for electrochemical decomposition of superalloys

Abstract

A process for recovery of valuable metals from superalloys by electrochemical decomposition is described, both electrodes being formed by the superalloy and the polarity of the electrolysis current being reversed with a frequency of from 0.005 to 5 Hz.

What is claimed is:  
     
         1 . Process for recovery of valuable metals from superalloys comprising decomposing the superalloys electrochemically, wherein the superalloy are used both as the anode and as the cathode, and the polarity of the electrolysis current is reversed with a frequency of from 0.005 to 5 Hz.  
     
     
         2 . Process according to  claim 1 , wherein the superalloy contains one or more of the metals Co, Ni, Cr or Al as major constituents and one or more of the elements Ta, Re, W, Mo, Hf or Pt as minor constituents.  
     
     
         3 . Process according to  claim 2 , wherein the superalloy contains from 1 to 10 wt. % of Re.  
     
     
         4 . Process according to  claim 1 , wherein the electrochemical decomposition is carried out with an electrolysis voltage of from 2 to 6 volts at a constant electrolysis current.  
     
     
         5 . Process according to  claim 1 , wherein an inorganic acid is used as the electrolyte.  
     
     
         6 . Process according to  claim 5 , wherein an oxygen-free inorganic acid is used.  
     
     
         7 . Process according to  claim 6 , wherein as a result of the electrochemical decomposition, the elements Co, Ni, Cr and Al are obtained as salts dissolved in the electrolysis brine and the elements Ta, W, Hf and Pt are obtained as filterable oxides, so that essentially quantitative separation of the two element groups can be carried out by filtration of the electrolysis brine.