Patent ID: 7520973
Filing Date: 2009-04-21
Classification: C23F,C23G

Abstract:
1. Method for regenerating from an etching system an etching solution containing iron for the use in etching or pickling copper or copper alloys, comprising: (i) feeding the etching solution to be regenerated from the etching system into an electrolysis cell comprising a cathode, an inert anode, means for removing the electrolytically deposited copper from the cathode and means for collecting the removed copper and applying a potential to the removed copper, wherein the electrolysis cell does not have an ion exchange membrane or a diaphragm, wherein the electrolysis cell is constructed to channel the etching solution such that the solution contacts the cathode of the electrolysis cell first, and then contacts the anode, and then exits the electrolysis cell, and wherein the electroylsis cell is a closed system which prevents gas from escaping from the solution; (ii) electrolytically depositing the copper comprised in the etching solution at the cathode, (iii) oxidising the Fe(II) comprised in the etching solution to Fe(III) at the anode, (iv) removing the copper deposited at the cathode, (v) applying a potential to the removed copper to prevent re-dissolving of the copper, and (vi) returning the etching solution being thus treated to the etching system.