# how to handle P2O5 as desiccant

## Recommended Posts

I am tryng to use P2O5 as desiccant to dry the atmosphere( air) in a glove box. In the glove box there will be maybe small amount of evaporated HCl. because P2O5 is corrosive, not easy to handle. therefore, could somebody give me any advice how to handle the drying process at best.

##### Share on other sites

why can't you just use silica gel?

its much safer, isn't as exothermic and doesn't form that coating which limits the dehydrating effects.

P2O5 is not usually used as a dessicant outside labs because it is pretty corrosive.

##### Share on other sites

I also use silica gel as the first dryingstep. but it has not so strong dehydrate ability as P2O5. so I try to use P2O5 for further drying because I need a very dry atmosphere with very humidity.

##### Share on other sites

Lithium Bromide, thats what you should use.

however if its to Absorb HCl fumes, then plain anhydrous NaOH will suffice.

P4O10 is indeed corrosive also, but Useless for absorbing acid fumes.

##### Share on other sites

What are you doing that needs that dry an atmosphere?

Anyway, the water permeation through the gloves will make more difference than the drying agent you chose.

##### Share on other sites

actually, i am doing exeriments using AlCl3, which is very sensitive to humidity. the possible HCl comes also form AlCl3.

what will be the advantage of Lithium Bromide compard to P2O5?

because I had never used P2O5 before, so I do not know how to use it safely. That is my qustion.

##### Share on other sites

LiBr is one of the better desiccants and much less reactive than P4O10, And it can be reused.

if you have some anhydrous NaOH in there also (powder not Prilled) it also will work as a desiccant (not as good as LiBr), but it will lock up any stray HCl fumes.

dont use the Carbonate of sodium though, it actually gives OFF water of crystalisation, exactly what you dont want to happen

## Create an account

Register a new account