PROCESS FOR ELECTROCHEMICALLY DISSOLVING A METAL SUCH AS ZINC OR TIN

摘要

The object of the invention is to provide for an improved electrochemical dissolution process for electrochemically dissolving a first metal by simultaneously creating hydrogen evolution at a second metal, the second metal being a metal that has a larger current exchange density for hydrogen evolution than the first metal, both metals being immersed in an aqueous electrolyte system, wherein the first metal and the second metal are galvanically coupled. By taking measures to reduce inhibition of said hydrogen evolution at said second metal the rate of dissolution of the first metal is enhanced. The measures to reduce said inhibition comprise suitably selecting temperatures and concentrations of the electrolyte, dividing the electrolyte into two fluids coupled by a selectively permeable device and suitably selecting the resistance value of a connecting means electrically connecting the first and the second metal. The invention is particularly useful for removing Zn or Sn from Zn- or Sn- containing steel scrap.