Does anyone have information regarding
the treatment of copper sulphate plating solutions for organic contamination.
We do this approximately once a year on
all solutions and have been using the following method:-
0.5-1.5gm/litre of Potassium
Permanganate depending on level of organics
Agitate for 2 hours
0.5 ml/litre of 35% Hydrogen
Peroxide
Agitate for 1 hour
Heat to 60 C (140F)
Add 2gm/litre
of activated carbon
Continue with heat and agitation for 2
hours
Allow to settle and filter pump to storage tank as soon
as possible to prevent organics leaching back into solution from
carbon.
Conversion factors ( g/l x 0.134
= 0z/US gal) & (1
litre = 0.264 US Gals)
This method is very effective at
removing the organics but I would like to know more about how this works. My
concern is the level of Manganese left in the solution after treatment.
We recently tried using peroxide only
and carbon but this did not reduce the organics sufficiently. We are told there
is a finite number of times where permanganate can be used before the bath has
to be replaced.
Is this method likely to cause a build
up of manganese and is there any alternative?
Many thanks for any
information
Paul
Gould
Teknacron Circuits
Ltd