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Procedure for Titration of ferric chloride ?

Does anyone know a specific test method for titrating a ferric chloride ⇦this on eBay or Amazon [affil links] etch solution, (i.e., what is the oz/gal of FeCl3)? The tank has been made up of 45 oz/gallon FeCl3, and 12% by volume HCl. I have a test method for ferrous chloride and total iron, but not ferric chloride ⇦this on eBay or Amazon [affil links] .

Travis Larsen
Gear Manufacturer - Park City, Utah
2003

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Didn't you answer your own question? You can measure ferrous and you can measure total Fe. Well, the difference is ferric.

Jon Barrows, MSF, EHSSC
GOAD Company

Independence, Missouri

2003

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2003

Dear Sir,

we utilise such a solution with Hydrochloric Acid at 100-120g/litre and ferric chloride ⇦this on eBay or Amazon [affil links] Hexahydrate at 400-500g/litre concentration.

To analyse for ferric chloride ⇦this on eBay or Amazon [affil links] potentiometrically, I take a 0.5ml sample of process solution, dilute to 100 mls with de-ionised water and add 5 gms of Potassium Iodide together with a small bar magnet to stir the solution then run the sample on the auto-titrator with 0.1N sodium thiosulphate ⇦this on eBay or Amazon [affil links] solution. The end-point comes at approximately 17mls of Sodium Thiosulphate (usually about 250mV)

If you have such equipment at your disposal I would give it a try!

Good luck

Nigel Gill, B.Sc. MIMF
- Blantyre, South Lanarkshire, Glasgow

Where did you get you method for Ferrous Chloride?

Scott Gray
testing - Latrobe Pennsylvania
December 3, 2009