Jump to content

Question regarding chemically removing aluminum from a copper surface

Recommended Posts

I have a decorative piece of copper with a rough surface which, due to it's fabrication process, has some embedded aluminum particles in the copper surface.

I cannot remove the aluminum from the copper surface by grinding or polishing because it would damage the decorative nature of the piece.

After giving it some thought I remembered that an aqueous solution of copper sulfate and salt (non-iodized) is a very effective way to etch aluminum.

My theory is that if I submerge this piece of copper which contains embedded aluminum particles into an aqueous solution of copper sulfate and salt that the decorative copper surface will be unaffected, but the aluminum will react to form aluminum sulfate and loose copper particles thus permanently removing the aluminum from the copper surface.

Am I overlooking any potentially dangerous reactions by simultaneously combining copper, copper sulfate, aluminum, and salt, or does this sound like a safe and viable solution?

Link to post
Share on other sites

Your idea should work fine.

My first thought would have been to remove the aluminium by dissolving it in sodium hydroxide solution.

Either option may damage any patination.

Also, in either case, wash the piece thoroughly after treatment before letting it dry.

Edited by John Cuthber
Link to post
Share on other sites

The coppersulfate solution will probably react with the aluminium and cover it with copper (immersion plating). Better is to use a dilutet solution of an acid . Copper is resistant to dilute acids, like hydrochloric, sulfuric or acetic acid. Aluminium will be dissolved.

Edited by chenbeier
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.