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

Recycling of Chrome Hydroxide cakes from plating solution

The plating industry generated Chrome containing solutions which are treated with sulfuric acid and then neutralised with lime to get Chrome Hydroxide cakes. But these cakes again needs to be converted to a product as otherwise it has to go only for land fill.Landfill is most expensive in Bangalore city, India and hence would you suggest a way to recycle chrome hydroxide to a better product which can be put to use again.

Sharad Shah
Metal recycler - Bangalore,Karnataka, India
January 7, 2010

---

January 23, 2010

The best solution to this problem is to avoid generating the waste in the first place. Pollution Prevention (P2) measures are available for chromium plating, chromium anodizing, and chromating processes.

Eliminating the chromium waste at the source (rinse tank) is always more effective and results in the best economic option compared to trying to reclaim chromium from a hydroxide cake that is contaminated by many other metals and undissolved lime.

The possible P2 measures include evaporation, ion exchange, and electrolytic diaphragm and membrane processes. Since you did not write which type of process is generating the chromium waste, it is not possible to say which of these might apply to your particular situation.

I recommend that you look in this direction instead of trying to make a re-usable by-product.

Lyle Kirman
consultant - Cleveland Heights, Ohio