Home /
T.O.C.
FAQs
 
Good
Books
Ref.
Libr.
Advertise
Here
Help
Wanted
Current
Q&A's
Search 🔍
the Site
pub Where the world gathers for
plating, anodizing, & finishing Q&As since 1989





-----

Nitric acid changed colour if aluminium sheet dipped overnight for a particular lot.





April 6, 2012

Q. Dear Sir,
Good Day,
Sir, once again I am here. Recently I took a lot of anodising. This coil job first was cleaned in caustic soda. After rinsing it was dipped in dilute nitric acid for neutralising. After overnight dipping (which was by mistake), in the morning I found that the colour of the nitric solution became golden. It is not the same for other lots. Whether there is any particular problem with aluminium sheets we do not know.
Please help. How to retrieve nitric to original.

S. Tambe
Hobbyist - Raipur, Chhattisgarh, India



April 6, 2012

A. Hi, Tambe.

Sorry, but I can't quite be sure whether you are saying that the aluminum became yellow or the dilute nitric acid became yellow. But if it is the nitric acid, your only practical option seems to be to treat and discharge it and replace it.

Regards,

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey


none
finishing.com is made possible by ...
this text gets replaced with bannerText
spacer gets replaced with bannerImages

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact    -    Privacy Policy    -    ©1995-2023 finishing.com, Pine Beach, New Jersey, USA