01-17-01 01:25
No 83183
today I was wandering around in the local hardware store, and I found a bottle of furniture cleaner that had listed on the back for ingredients, "Contains Gamma-Butyrolactone and 1-Methyl-2Pyrrolidone". Is this right? I though GBL was banned in the US. well, I'm also wondering at the same time if anybee knows of a way that these two chemicals could be separated? they're boiling points and melting points are almost identical, as well as they're solubility in water. they're structure makes them look like they would have similar solubilities in different solvents. Any ideas on separation would be appreciated.
You expect me to sign my name here? I can't get the mouse to write anything.
(Chief Bee)
01-17-01 10:33
No 83268
(Rated as: excellent)
The boiling points of N-methyl-pyrrolidone (202°C) and gamma-Butyrolactone (204°C) are way too close for it to be possible to separate them by vacuum distillation. Also, take note of that the auto-ignition point of NMP is 270°C according to its MSDS1, so do NOT subject either pure NMP or a NMP/GBL mixture to excessive heat!
Thus, for separation of the two compounds, you have to resort to another scheme, and my best suggestion for this follows here. The scheme works perfect in theory, but has not to my knowledge been tested in practice by anyone, so please exercise caution, and also report back to me if you have performed this separation like suggested here, or in any other fashion for that matter.
Vigorous basic hydrolysis2 of a mixture of N-methyl-pyrrolidone and gamma-butyrolactone would create 4-hydroxybutyric acid and N-methyl-4-amino-butyric acid (N-Methyl-GABA). Mild acid treatment3 of this mixture would preferentially esterify the GHB to GBL, while still leaving the amino acid in its zwitterionic form - amides form much less readily than lactones, especially in aqueous solution. The formed GBL could then be continuously extracted from the reaction mixture4 with a water-immiscible solvent in an extraction apparatus or by allowing the mixture to cool and make a solvent extraction in a sepfunnel every 20-30 minutes until no more GBL is retrieved. Yet another alternative method would be to steam distill the GBL from the hydrolysis mixture as it forms adding water at the same rate it distills off. Finally the distillate is extracted with a water-immiscible solvent from the GBL/water mixture.
Finally, regardless of method chosen above, you now have a solution of crude GBL in a non-polar solvent, and pure GBL is isolated by drying the solution over anhydrous MgSO4 or similar, filtering, evaporating the solvent (preferably under vacuum, collect it for reuse!), followed by (fractional) vacuum distillation of the GBL (Important!). It is possible to do without vacuum, but it is a bit impractical as the bp of GBL is 204°C at atmospherical pressure - something really requiring a heating mantle. During this distillation (which is to be conducted very slowly, 1-2 drops a second), watch closely for any distillate coming over below 204°C and discard this and the first 10-15% of the GBL (as it likely contains/consists of NMP, bp 202°C - this portion is not lost however, as you can resubject it to the above separation again).
[1] MSDS: N-methyl-pyrrolidone (NMP) (http://www.astrochemicals.com/25083.pdf
[2] Reflux with 2-3 molar equivalents of 30-40% aqueous NaOH or KOH for a while, maybe 1-2 h? Check Vogel's book (../rhodium /vogel3
[3] Acidify to pH 2-3 with 25% w/w HCl or H2SO4, heating to maybe 40-50°C with good stirring.
[4] Continously shifting the GHB <-> GBL equilibrium to the right, which is around 1:1 or 1:2 in an aqueous solution.
(Newbee)
01-18-01 00:25
No 83408
once again, thanks rhodium. I'll try this out this weekend when I get some free time. how come the two chemicals could have a different boiling pressure under vacuum when they have almost identical boiling points at 1 atm? I tested out my vacuum for the first time last night, and it could boil asarone at 35C. guess I might have to rig something up to reduce the vacuum I'm pulling. If I get it to work, I'll come back and post what I did.
You expect me to sign my name here? I can't get the mouse to write anything.
(Hive Bee)
01-19-01 03:45
No 83629
I thought we already went through this. Didnt cheapskate or someone else successfully ingest this compound after fixing it? I remember the pm when it first came out. Could you (joe) pm me the namebrand and region of the US you live in. I dont remember the name anymore, but never saw it back in summer, maybe its a thing in my particular state.
(Hive Bee)
02-01-01 04:43
No 170421
Joe said > How come the two chemicals could have a different boiling pressure (points)? under vacuum when they have almost identical boiling points at 1 atm? <
I've wondered same eg water BP 100, comes over @ 50ish under full vac. Toln BP 110 comes over 25ish, same vac ???
I'm sure any school boy could tell us, but I was a sickly child so was absent that day.
(Stranger)
03-14-01 15:53
No 178428
if you've got the time...
please pm me too with brand of cleaner
thanx ;)
(Stranger)
03-17-01 16:27
No 179023
It seems to me crissaris(?) had some posts on this also. The product she talked about was in a clear jug and was kind of yellowish. I think it had been denatured. I was found at a blue home store.
rollin,rollin,rollin
(Stranger)
03-23-01 04:36
No 179979
I wouldn't try that...
(Hive Bee)
05-22-01 18:39
No 196135
its catharsis damnit.. and hi rollin.. i know this is a bit old but i just saw it. this is the same bottle i had..the contents the same.. is rhodium saying tresting it with acid (h2so4?) will give somthing that can be extracted with a non polar solvent and evap to get GBL? then distill?
I'm doubting this.. but id like to frickin know since i asked this almost back in 1999.. GBL has also been found in about 6 other over the couter cleaners and things of that nature. (if you wanna know these brand names i dont know, 'cause i figured the other contents would have the same boiling point as GBL like thiee methyl-prolione(spell it i dont care)) this was found at (whats a blue whatever?) an outlet for hardware goods.. if you want to know the name ask me...one person did already..
but more importantly if you have any info pretaining to getting the GBL please let me know by PM. or email..
postive energry activates constant elivation. -gd
(Hive Bee)
05-23-01 16:16
No 196436
I'm more into E, K and similar drugs, but I do like a drink of GBL every once in a while. Do any of you folks remember when it was legal to buy those two component(GBL/NaOH) kits? Those were kick-ass! Ever since the U.S. government fucked us over with yet another stupid fucking drug law, I've been trying to find a decent patent for GBL. The refs on Rhodium's page were helpful, but I'm still looking for more patent #'s, because I don't feel like experimenting with paint-stripper or other solvents. Alternative: Get a job in a part of the industry that uses GBL. Making a career movement to support a small habit might seem kind of drastic to some, but if they pay good, and provide health insurance/retirement, then I'm happy
I'm going to help all of you cleanse this diseased planet.
(Newbee)
05-23-01 17:26
No 196456
There are some "cleaning companies" that sell pure GBL online for removing varnish. Funny, thats there only item.
(Stranger)
06-19-02 11:15
No 323019
A stripper contain 20% NMP 50% GBL. Instead of a basic hydrolisis of the distillate, whatdoyou think of an acid hydrolisis with HCl, this will form 4-methylamino-butyric acid HCl which is a salt with mp 125°C wile the lactone/ghb will still bee in free form so a vac distillation at 100°C will effectively separate the two components (lactone bp 89 C @ 12 mm Hg).
Any comment?......????.