G Impurities and NMP

[malsat]

Just thought I'd clear something up.

A number of web forums I've been to have mentioned NMP (N-methyl-2-pyrrolidinone, http://en.wikipedia.org/wiki/N-methylpyrrolidone) as a contaminant of GHB/GBL and discussed the potential health effects of this compound and possible ways of removing it from a G solution. The whole idea that this is a possible contaminant originated in an issue of the DEA's Microgram bullitin. They analysed an aqueous 470ml sample and found it to contain a 2:1 NaGHB:NMP mixture. I've found no other evidence indicating that NMP is present in any G, anywhere. There is no reason why NMP would be a contaminant in G. Commercially, NMP is produced from GBL. It would make sense that NMP could be contaminated with GBL, but not vice-versa, unless there was some contact or storage contamination that occured at a manufacturing plant. So we can all stop worrying about that.

The majority of GHB available to rec users is produced from GBL, with a smaller amount produced through GBL from BDO and THF (I'm not sure if either of these are used as industrial precursors, but no doubt there are clandestine labs using these methods) and some would be produced from GABA. That produced from GABA will likely have some 4-chlorobutyrate and other contaminants present, while the majority of GHB/GBL available will have some BDO and THF. There will be some heavy metal contamination but I don't know if they're present in levels to be concerned about. Heavy metals are everywhere anyway.

What really bugs me is all the damn filth and semi-dissolved HDPE that ends up in the bottom of a bottle of GBL. Nasty >

[Psych0naut]

SWIM always gets 99.95% pure GBL, nothing of lower purity. SWIY could try seperating both chemicals by disstiling, if SWIY has the equipment.

[agent47]

I vaguely recall this being mentioned in the Microgram Bulletin, and I've attached the Microgram entries I think you're referring to.

NMP itself is typically contaminated with GBL and the dimethy isomers 1,3-dimethyl NMP, and 1,4-dimethyl NMP along with N-methylsuccinimide.
The N-methylsuccinimide is a decomposition product from oxidation.

I've attached a chromatogram showing GC elution order. Relative retention times would be useful for assay of GBL/NMP mixtures and impurities encountered.

Note: Sample shown in chromatogram stabilized with BHT at a level of about 0.032% wt. to prevent NMP oxidation.

GC conditions were follows:

Instrument: .........................Hewlett Packard 6890 gas chromatograph
Detector:..............................Flame Ionization (FID)
Carrier Gas: ..........................Helium
Column: ...............................5% phenyl-methylpolysiloxane capillary column, 30m x 0.32 mm x 0.25 mmfilm thickness

Column Flow Rate: 3.0 ml/min constant mode (initial head pressure 14.1 psi, average velocity 47 cm/sec)

Injector Temperature: .................................................. ....200 °C
Split Ratio: .................................................. .......................100:1
Split Flow: .................................................. .......................299.0 ml/min
Total Flow: .................................................. .....................304.3 ml/min
Injection Size: .................................................. .................1 microliter
Detector Temperature: .................................................. ...320 °C
Makeup Flow: .................................................. .................45.0 ml/min helium, constant mode
Hydrogen Flow: .................................................. ..............40.0 ml/min
Air Flow: .................................................. ..........................450.0 ml/min

Oven Program: .................................................. ..................Initial Temperature 70 °C
Initial Time .................................................. ........................1.00 min
Rate 1 .................................................. .................................1.0 °C/min to 79 °C, zero hold time
Rate 2 .................................................. .................................25.0 °C/min to 300 °C, 1.16 min hold time
Run Time .................................................. ...........................20 minutes

[agent47]

Initial Microgram Bulletin entry attached.