Will there still be slight reactions in the concentrated sulfuric acid storage tank after passivation?
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We know that steel becomes passivated in concentrated sulfuric acid and concentrated nitric acid, with a passivation layer forming on its surface to prevent further reaction between the steel and these acids. Therefore, concentrated sulfuric acid can be stored in steel tanks. I wonder if a steel storage tank for concentrated sulfuric acid will have no slightest reaction with the concentrated sulfuric acid stored in it? If not, the storage tank can be used for a long time; as long as its outer surface is protected against corrosion, it can remain in use indefinitely. If there is a mild reaction, what is the reaction mechanism, and will hydrogen be produced? Is there a specified service life for sulfuric acid storage tanks? I earnestly request advice from fellow travelers
There will be a slight reaction, and hydrogen gas will be produced
I wonder how noticeable such a reaction is – whether steel sulfuric acid storage tanks used over a long period of time will experience significant hydrogen accumulation, thereby creating a mixture of explosive gases? A highly experienced senior technician holds a negative view on this, as he believes that concentrated sulfuric acid will no longer react with passivated steel.
As long as the passivation film is present, there will be no reflection anymore； In other words, as long as the concentration of concentrated sulfuric acid in contact with steel does not change significantly, no reaction will occur.
There will be some degree of corrosion, and the cost of using materials resistant to corrosion solely for the storage tank itself is relatively high. Under normal temperature and pressure, a fiberglass storage tank can be used directly ； Or carbon steel with rubber lining, rotational molding of PO and PE, along with internal glass flake coating for corrosion protection.
So far, the sulfuric acid storage tanks that I have come across are mostly made of steel, while smaller tanks for dilute sulfuric acid are sometimes made of fiberglass; I have not seen any tanks with other types of anti-corrosion linings. Do you have any information on this that you can share?
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My goal is not corrosion prevention, as this is hardly a concern when steel storage tanks are used to hold concentrated sulfuric acid. I mainly want to know whether, after the surface of steel is passivated by concentrated sulfuric acid, it will still have a slight, ongoing reaction with the acid. Even if it’s just a slight reaction, over time hydrogen gas could accumulate. I’m not sure if my concern is unfounded
Theoretically not, but in actual production. Because sulfuric acid is flowing or fluctuating. The membrane will experience wear and tear. Sulfuric acid storage tanks can produce acid sludge.
Do everyone agree with the view that hydrogen will accumulate in the concentrated sulfuric acid storage tank? Although no hydrogen was detected, there is still some concern when performing hot work; some consider this worry to be unnecessary – is it really just unfounded anxiety?