Sciencemadness Discussion Board

Drying Sodium Hydroxide

Crypto - 13-1-2014 at 15:37

Any thoughts on drying hardware store bought NaOH ?

alexleyenda - 13-1-2014 at 15:40

I guess heating it to 130°C and letting it cool in a dessicator should get the job done.

UnintentionalChaos - 13-1-2014 at 15:43

Don't bother, the only good way to dry it is to heat it while molten after which you still have to grind it up again. Most uses of sodium hydroxide will tolerate a few percent of water. You're better off titrating it and adjusting the amount used. Most preps will also tolerate excess and 5-10% excess should cover for any water content.

ScienceSquirrel - 13-1-2014 at 15:59

If it is little dry white pellets or flakes I guess it is at least 95%, probably more.
I buy 98% food grade sodium hydroxide as mini pellets for use in brewery cleansing from an approved brewery supplier.
It is a free flowing solid that does not stick together if kept dry.
Things to look out for are sticking together or white efflorescence.
This shows the absorption of water and / or carbon dioxide.
Molten sodium hdroxide is evil stuff and best avoided.