Vacuum evaporating water from CWE?

[speedo]

I was curious as to what precautions one should take before attempting this on a rather significant amount of liquid. Would a 20-30 psi water aspirator vacuum pump be adequate for a job like this? Does this process pose any significant risk to the codeine?
(Codeine freebase not codeine hcl!)

 

[adder]

So you mean a vacuum pump or a water aspirator? A water pump is definitely not enough to speed up water evaporation in a significant way. With a vacuum pump it is certainly feasible but you might still need to heat the solution a little bit. The process has no effect on codeine.

Am I correct that you have codeine freebase dissolved in water? Codeine is very poorly soluble in water, so if it is indeed an aqueous solution of codeine freebase, then a much better idea would be to simply extract codeine into an organic solvent.

EDIT: Ah, it just got to me what you really meant. I'm not sure how much vacuum you can generate with your water aspirator. Water aspirators using tap water I work with typically generate enough vacuum to make filtration fast and perhaps slowly evaporate diethyl ether, so I can't help you more on this. :/

 

[sekio]

Water tends to bump quite violently under vacuum, be careful you don't end up sucking all the codeine down the drain (or backing up water into your codeine sol'n)

 

[d1nach]

Whats the point of this? Sounds so painfully slow you mine as well leave it out on a pan and let it evaporate

 

[Nexus_Tripper]

You might want to salt the codeine as the freebase is more volatile. Your pump shouldn't be powerful enough to sublimate any significant amount, but it's better to be safe than sorry.

 

[Nexus_Tripper]

Whats the point of this? Sounds so painfully slow you mine as well leave it out on a pan and let it evaporate

Vaccums rapidly boil and suck liquids. Boiling off the H2O is much faster than evaporating at RTP (room temp/pressure).

 

[adder]

This is very impractical nonetheless if you can easily turn a salt into a freebase that can be extracted into an organic solvent which will be much easier to evaporate (or even better gassed with HCl to precipitate codeine*HCl and then filter it). With solvents that have a high boiling point (say, >100oC) evaporation of larger volumes even under vacuum can still be slow at room temperature and evaporation to dryness is also often problematic either taking long time or being almost impossible with certain compounds.