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fast and easy to re-generate, either chemically or by electrolytic
recovery. Not suitable for PTH work as it readily attacks tin lead.
Normal copper etching reaction is:-
Cu
+ CuCl2 >> Cu2Cl2
Simple
chemical re-generation is possible by adding HCL and enough H2O2
to re oxidize the cuprous chloride to cupric chloride. Excess free
peroxide in solution, especially when combined with elevated temperature
can result in liberation of toxic fumes. Given time or less time and
air agitation the re oxidization will take place without the addition of
the peroxide.
