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Removal of iron traces from sulfuric acid bath for extending working life of acid

2004

Dear friends,

I am a materials researcher who was recently asked by an industrial friend if there is any commercial equipment, system or process by which the iron traces left in the sulfuric (and chloride) bath can be quickly and efficiently removed so that their acid baths can extend their working life for continuing pickling the iron oxide traces formed on the wire-rods (descaling), as a part of their pre-treatment before wire drawing. The concentration of iron in the acids might be as high as 50g/l and the tanks volume of nearly 5,000 litters. The point here is to find any solution by which both the iron and acid bath dumping do not make bigger our environmental problems.

Any comment is greatly appreciated.

Sebastian Diaz
research - Mexico, D.F., Mexico

There are a few companies in the UK selling acid recycling equipment which use diffusion dialysis technology (membrane separation process) to separate contaminants, including iron, from the solution. I'm sure it wouldn't be too difficult to find a company in your part of the world which sells the same type of equipment.

Dougie Lightfoot
- Fife, Scotland
2004

I was reading the EVENTS section at this site and entered the southeastern something event that was the first few days of Sept. One of the sponsor sites for that event was Pro-pH. I clicked on their web site and was surprised at the amount of information and testimonials. Some from companies that I am familiar with. It sure sounds good, if you can believe the hype.

James Watts
- Navarre, Florida
2004

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I met David French of PRO-pHx, who was demonstrating at that conference, Jim, and it sounds like a good product. They don't claim to actually regenerate the acid, but they do claim that the material causes the metal to precipitate out and become filterable, thus extending the life pretty dramatically.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

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Hi Ted

The hype on the product is exactly what the original author asked for. I did notice that it is not a regeneration such as you might get from electrodialysis or similar procedure (which ain't cheap or easy).

James Watts
- Navarre, Florida
2004