The authoritative public forum
  for Metal Finishing since 1989
-----

Carbon filtration for e-nickel chemistry

I have heard of using activated carbon for removal of organics in electroless nickel plating applications. My company supplies filtration products to the electroless nickel plating for hard disk drives. We have an end user who would like to add a carbon filtration step into his system. However, which type of activated carbon should be used, coconut or anthracite based carbon. Are there any flux requirements, limitations, etc. Are you aware of any papers or technical articles that have been published on the use of carbon filters in hard drive disk plating.

Thanks for your consideration,

Thomas Burt Gutowski
filtration products - Timonium, Maryland, USA
2003

---

Carbon filtration can be used , preferably for short times to remove accidental organic contamination. The carbon must be sulfur free! However, bear in mind that carbon will remove an unknown amount of stabilizer from the EN solution. The plating solution for memory disks is very critical in terms of consistent composition. Many contaminants (some of which are found in carbon) will change the magnetic characteristics. It is essential to produce a nickel-Phosphorus deposit that is non- magnetic, and remains so at higher temperatures, i.e. 300 C.

Don Baudrand
Consultant - Poulsbo, Washington
(Don is co-author of "Plating on Plastics" [on Amazon or AbeBooks affil links]
           and "Plating ABS Plastics" [on Amazon or eBay or AbeBooks affil links])
2003