Australia's Science Forum

Hi All,

I have a container of red phosphorus that has absorbed so much moisture that it is now more a paste than a liquid.

Any ideas on how to go about dying it out? Our HOD suggested putting it in an incubator. I'm just a bit cautious about doing this.

Thanks Lorrae

Dear rae,
I think you are very wise in not dealing with this chemical once its composition (and probably its formula) has changed. I'm sure Robb would agree. Read its MSDS and dispose of it carefully. I have had this happen to red phosphorus due to age or exposure to air. It becomes deliquescent. It can be explosive. Keep isolated and secure until you can dispose of it with a waste disposal contractor.
Cheers,
~Robyn

Phosphorus in the past was often stored under water as a satety measure!
Just use a spatula to scrape some from bottom and place on watch glass to air dry "should not be a problem this weather"

Hello,
I am with ri on this, dispose of the entire container with a disposal company. We had some very old red and white phospherous a few year ago and even putting it in a new botttle under water, old one had broken lid, resulted is flare up.

Best policy with old and questionable chemicals is it is safter to dispose then risk an incient.

Regards
Michelle

I agree with those who suggest you dispose of it. Not worth the risk.
Carolg

Hi All,

If you are looking at the possibility of reclaiming the Phosphorus back I would place this into a desiccator, and allow for the moisture to be absorbed by the desiccant.

This would be a safer option than leaving it out to air dry as the Phosphorus would still absorb moisture from the air, and the odour would also be a problem.

Spread this out into a evap basin or onto a watch glass to increase the surface area to be dried and wait until the desiccant does the trick.

As I mentioned earlier, this would be a safer option but personally I would dispose of this due to the moisture absorption making the P somewhat unstable.

Hope this clarifies some doubt.

Robb...