Although this will be a bit later for the OP, Butabital can be fairly easily seperated from all the crap it's often formulated with such as Caffeine, Aspirine, Paracetamol, or what else. The way to accomplish this is through acid-base extraction. When acidified, barbiturates will become the corresponding barbituric acid. When an alkali hydroxide such as NaOH is added, it turns into the alkaline Sodium salt. The free acid of barbiturats is highly insoluble in water, but the alkaline Sodium salt is very soluble in water. So taking this in account, it can be seperated from other stuff you don't want in your end product.
So, by adding any butalbital containing mixture to a basic solution of NaOH, it will dissolve very well in water and sol will the the caffeine, the paracetamol will not.
Filter the solution to get rid of the paracetamol. Now add small portions of hydrochloric acid to the solution left over after filtration untill no more Butalbital precipitates out of solution. Filter the solution and keep the you'll see the butalbital precipitating as it's free acid, but the caffeine will stay dissolved. Filter the solution and throw away the liquid, the stuff that's in the filter is your Butalbital as it's free acid. You can use it as is for oral consumption it doesn't matter much whether it's as free acid or as alkali salt (it's just as corrosive either way). Njoy!
