Boiling off chems to get GBL?

overflow · Thu Sep 29, 2005 3:55 am

A friend recently found an OTC solution that is largely gamma butyrolactone. Problem is, the solution also contains nitromethane, isopropyl alcohol, ethyl acetate, and acetone. My friend would like to isolate the GBL from these other nasty chems. Given that they all have a boiling point much lower than the GBL, can my friend just boil off the other chems? My friend would like to avoid distillation if possible, but wants to make sure boiling won't create any new dangerous compounds. Will this work? Thanks in advance.

jooboy · Thu Sep 29, 2005 10:54 am

It works a friend of mine tried it. But the finished product had a yellow tint to it. Anyone have any ideas?

64bandil · Busy Bee

Yes - it would mostly remove the lower boiling stuff. However, as this is meant for human consumption, you really need to purify it descently. You can purify it quite alot by A/B workup. NaGHB is soluble in water, and GBL is somewhat insoluble in saline water.

But, your cleaning agent contains nitromethane, which forms a very unstable and explosive compound upon contact with a strong base (such as lye). I do not know the exact parameters nescassary for removing it safely, but keep this in mind when you are purifying it!!! Do not simply add lye to the cleaning agent, expecting pure GHB to float in your water phase - you will most likely get more than you bargained for.

Bee safe!

Regards
Bandil

loki · guinea pig

here's an idea for how to clean it up

mix sodium bisulphite with it and precipitate the gbl (am i mistaken for thinking this is possible, it is a ketone after all, so it should form the adduct), if gbl will form the adduct so will the acetone. filter the rest of the crap out and wash with some appropriate wash (IPA or denatured alcohol). then drive off the sulphite with HCl and then basify to yield the GHB as sodium GHB which has a much higher bp than acetone and boil it out and then acidify and wash with brine to remove all the crap separate to yield relatively pure GHB.

overflow · Thu Sep 29, 2005 5:55 pm

Thanks for the advice everyone. My friend got anxious and tried his boil method before I could get him to try your suggestions. He heated the solution to 280F on a hot plate and held it there for a good hour or so. I'm told the acetone and IPA scent went away very quickly, so he was thinking they were only in the solution in minute quantities. After that, the smell was identical to that of pure GBL. Not much volume was lost at all. As jooboy stated, however - the GBL did take on a slight yellowish tint (very slight.) He thought this might be because he may have slightly burned the remaining GBL (not 100% sure though.) After that, my friend went on to perform the conversion using sodium hydroxide and everything looked normal - it bubbled up nice and violently. My friend ingested a small quantity and the effects were just as expected, but he still worries about that yellow. What do you think?

joe_aldehyde · huxleys associate

GBL will decompose on standing, that's what the MSDS says. so probably heating accelerates decomposition. that may be where the yellow colour comes from.