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Filtering nickel sulfamate

My bath is contaminated and need to be filtered. Is it OK to use a charcoal water filter to filter a 2 gallon bath of sulfamate?

Ewald Schuster
education - LA, California, USA
September 9, 2009

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First of three simultaneous responses -- September 11, 2009

It probably will work, but you may need to filter it with a 5 or 10 micron regular filter afterward to remove any carbon fines that probably will escape. Also, all carbon is not created equal and non plating products may have metallic contamination in them.
You will need to re-establish your wetting agent(anti pit level) as it will be largely removed.
PS: the filter is now a haz waste.

James Watts
- Navarre, Florida

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Second of three simultaneous responses --

What is your bath contaminated with? A charcoal filter will take out organic species, but it is pretty hopeless at taking out particulates or many other metal ions.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
September 11, 2009

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Third of three simultaneous responses --

What is the contamination you want to adsorb on carbon? Try a small beaker [beakers on eBay or Amazon [affil links] first followed by a beaker plating test to see if the carbon did any good.

It is OK only if: (1) the mechanical parts of the filter are compatible and are not attacked by the plating solution, AND (2) the "charcoal" is sulfur free.

You would be better off on a 2 gallon solution to use a funnel, laboratory filter paper, and powdered activated sulfur-free carbon. Put the powder carbon in the solution (using a different container),stir for 30 minutes, and pour thru lab filter paper in a funnel letting it drip until it all came thru.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

September 11, 2009

I am plating fiberglass parts that were made conductive with silver paint, I believe that the silver paint sheds some of the silver before it is covered in nickel and this is contaminating the bath. Is charcoal the way to go?

Ewald
- Los Angeles
September 14, 2009

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"You would be better off on a 2 gallon solution to use a funnel, laboratory filter paper, and powdered activated sulfur-free carbon. Put the powder carbon in the solution (using a different container),stir for 30 minutes, and pour thru lab filter paper in a funnel letting it drip until it all came thru"

This is interesting way to do it, can I do it cold or at 160F?

Ewald Schuster
- Los Angeles
September 15, 2009

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First of two simultaneous responses --

A filter paper and gravity system will take forever. A large Buchner funnel and slight vacuum would be a lot faster. make up a new solution while you treat and test the old solution.
You will be glad you did.

James Watts
- Navarre, Florida
September 15, 2009

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Second of two simultaneous responses --

Do not exceed 120 F with sulfamate. At higher temperatures the sulfamate radical breaks down into sulphate and ammonia. The ammonium ion causes brittleness. First take a beaker, using room temp solution, put in the carbon, filter, test in the Hull Cell or beaker. Then do the same thing at 120F, compare the test panels and decide which way to go on the whole 2 gallons.

When plating on silver paint, be sure to start at very very very low current density, spend the first two hours gradually ramping up the current. If you go too high, too soon, you burn off the silver paint.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

September 15, 2009

So if it is the silver paint contaminating the bath will the charcoal filter remove all if the contaminants?

Ewald
- Los Angeles
September 19, 2009