Testing for free iron content in acidic solutions

I currently have 2 stainless steel passivation tanks. A 21% nitric acid solution with sodium dichromate and a 50% nitric acid solution. I also have a stainless steel etch tank filled with Wyandotte DS9-314. What is the lab procedure to check these solutions for free iron? The passivation and etch are in accordance with ASTM A967.

Lawrence Cole
- Ogden, Utah, USA
2002

An A.A. unit (atomic absorption) ⇦ on eBay or Amazon [affil link] .

Bill Hemp
tech svc. w/ chemical supplier - Grand Rapids, Michigan
2002

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

No dead threads!
Your Q, A, or Comment puts this thread on The Finishing.com HOTLINE.

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: