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Minimising copper in alkaline phosphate gold bath

How can I reduce copper in alkaline phosphate gold bath, Is there any complexing agent/precipitating agent which can reduce the copper level in my alkaline cyanide free phosphate gold bath where in copper should be less then 15ppm.

Panjala Mukesh
fashion jewelry mfgr.
Hyderabad, India
2005

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2005

Mr.Mukesh,
1.Ensure there is no drag-in of Copper to the gold bath.
2.If you plate copper prior to gold,install an air agitated hot water rinse tank.The swill time should be minimum 1 minute.
3.If your substrate is copper, make sure you live load the work in the gold bath.
4.If desiarable you can select a barrier layer of
a) 0.2 Microns of Palladium plating
b) 3.0 Microns of White/Yellow Bronze
or c)10.0 Microns of Nickel preferably Sulphamate Bath.

Again if you use White/Yellow bronze pl. make sure proper swill as these solutions contain Copper.

T.K. Mohan
plating process supplier - Mumbai, India

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I Thank for the reply Mohan, those are the measures to prevent the copper input to the Alkaline phosphate bath.I have fresh DI water running prior to alkaline phosphate gold bath, and I do Nickel as a barrier , still I get copper from racks as a smut/muck, that smut, I siphon twice a day. Do we have any coagulating agent to precipitate 25ppm of copper in Alkaline phosphate gold bath?

Panjala Mukesh
fashion jewelry mfgr.
Hyderabad, India
2005