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Storing concentrated sulphuric acid

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Poekus

Rising Star
Is it possible to store a bottle of concentrated sulphuric acid (95%) in the shed?

The reason why I am asking this, is that the melting point is only 10 degrees celsius, which would imply that the bottle freezes even when it does not freeze outside.

Will the acid decompose or even worse could the bottle explode by the pressure build up from the freezing/thawing process?

I googled it for some time but couldn't find any information on storage at sub 10 degrees temps.
 
Lock it in a metal cupboard. The temperature should not be an issue, only a very few things expand on freezing like water. Cooling things down does not generally cause decomposition, sulphuric acid can be distilled with only slight decomposition at 338°C.

wikipedia said:
When sulfuric acid is above 300 °C (572 °F), it will decompose slowly
Click to expand...
 
Thanks! I will store it a metal locker inside a plastic bin in case the bottle starts leaking.
 
Short answer is yes.

Note that Cleamen 420 drain cleaner is almost pure 98% sulfuric acid and it is stored in a HDPE bottle.

I store mine in a dark glass reagent bottle.

Sulfuric acid vapours are the least concern (the vapour pressure is below 1 mmHg!) up to 98%.

Vapours become a concern only with oleum, i.e. sulfuric acid fortified with sulfur trioxide, also called fuming sulfuric acid.

Note that commercial azeotropic sulfuric acid (96-98%) is an oily liquid, nothing like conc. oxidising acids that fume considerably, and require special storage (e.g. nitric).

Although it looks tame, be very careful when about diluting it and on contact with organics due to its strong oxidising action. Always keep some baking soda around to neutralize.

Of course keep your bottle well sealed as nothing can react with the acid in the bottle (e.g. water vapour).

Using a secondary container (e.g. HDPE box) partly filled with sorbent (e.g. vermiculite) is a good practice for long term storage.
 
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