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50% Sulfuric Acid Tank

I am engineering a storage tank to hold sulfuric Acid @ 50% concentration and a temperature of 230 Deg F. I can fabricate in any metal but need to know what the best lining would be. The tank will be square 20' x 24" w x 25" deep with a level of 20". I have checked into teflon but it becomes porous when sprayed. Porcelain will not hold up to the acid content. I am concerned about using glass due to how to seal the corners. Any suggestions?

John Rose
Metal Fabricator - Maryville, Tennessee, USA
2006

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2006

Hi John,

Why, I ask myself, why doesn't he consider pure plastics?

For a starter, how about PVDF which is good for l40 °C ...
I believe (but don't rightly know) that it can be painted on.... or, how about making the entire tank from PVDF ..
or Halar or FEP and armouring it with fibreglass, the so-called dual laminate approach. .... PVDF being less expensive than the fluorocarbons and loves acids.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

Freeman, boo boo. pvdf is a fluorocarbon. Looked up the definition to make sure.

James Watts
- Navarre, Florida
2006

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Yes, James. PVDF is a fluorocarbon ... but is at the bottom of the pile in temperature and high alkali resistance compared the far more expensive yet also weldable ones like Tefzel, Halar and FEP teflon ...

I should have added 'OTHER fluorocarbons'.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2006

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Freeman, how is high alkali resistance relevant to service with 50% sulfuric acid, which is about as far from alkaline as you can get?

Bill Reynolds [deceased]
consultant metallurgist - Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.
2006

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Bill,

I was only making a general statement ... namely, that PVDF is superb in acids but alkaline-wise, seems to have problems at pH l0 and over whereas the other fluorocarbons seem to excel.

Anyhow, another Melbourne-ite, Tony Johnston, P.Eng., might well agree with me. He'd better or I'd use a few bad words !

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2006