Metacelsus - 2-5-2014 at 12:48
I have a nearly full 100 milliliter bottle of some 10% benzoyl peroxide acne cream, which I now have no use for (due to not having acne). The other
ingredients are listed as water, poly(acrylic acid), sodium C14-16 alkyl sulfate, and methylparaben (methyl 4-hydroxybenzoate).
I'm interested in the benzoyl peroxide as a free radical initiator. How easy would it be to extract the benzoyl peroxide with a nonpolar,
nonperoxidizable solvent (such as xylene) and evaporate the solvent under vacuum (I can get xylene to boil at ~70 C with my aspirator) to get
relatively pure benzoyl peroxide?
If I used toluene I could get it to boil at ~50 C, but I'd rather use xylene because it's easier for me to get.
[Edited on 2-5-2014 by Cheddite Cheese]
Dr.Bob - 3-5-2014 at 14:09
It is possible, but still dangerous, so if you do it, be very careful, I have seen the result of a peroxide/solvent explosion, and it was amazingly
bad. Not sure if DCM is better, due to less flammability. You could even try to extract it as needed, then use the extract added to the next step,
that is how I try to handle peroxides, just keep the materials in solution until all peroxide is used up or destroyed. And in many cases, the amount
of peroxide needed can be quite small. Plus it is not terribly stable, and need to be kept cold to store. You might also want to look at the
purification of lab chemicals book to see if they tell how to purify it.
Metacelsus - 3-5-2014 at 14:14
The "extract as needed" idea is interesting. I might end up doing that, to avoid the danger.