-- The Home Page of the Finishing Industry
Serious Education & the most FUN
you can have in metal finishing smiley

No popups, spam, registration or passwords
on this site
current topics
topic 11591

Sulfurous acid as reducing agent for gold


Sulfurous acid is known to destroy the excess nitric acid and eventually precipitate gold from the gold-aqua regia solution. I tried adding an excess of 5-6% of its AR grade. After a while brown clouds appear and get denser. However, it also easily disappeared as the solution warms up. The solution's color turned from reddish orange to a much lighter yellow orange. What could possibly be wrong that the gold did not precipitate? Is it because I just got a trace of gold? Should I use another reducing agent as sodium meta bisulphite?

Tim Carino
- Philippines

If you have a question in mind which seems off topic, please Search the Site

ADD a Comment to THIS thread START a NEW threadView CURRENT TOPICS

Disclaimer: It's not possible to 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 may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices

©1995-2018, Inc., Pine Beach, NJ   -   About   -  Privacy Policy
How Google uses data when you visit this site.