[Biohpilic]

Hi all!

I have a few years of experience making extracts, mainly for dabbing. My preferred method as of now, given the materials I have, is to extract from plant material (buds if possible) using butane, and then mix with absolute ethanol for purging the butane and sometimes winterizing.

After a few unsuccessful trials, I have finally mastered the art of decarboxylating the extract in its final form, watching for CO2 bubble production to gauge the process. This has given me a wonderful orally active (and very potent) final product, which has already served people with chemotherapy pains, menstruation cramps, bronchitis, or desires to get high.

The thing is that I usually only do a one pass extraction with butane, so I am left with herb containing a decent amount of thc. I usually accumulate the weed from several batches and then make some cookies. Making cookies is boring, smells up the whole house, gives out a hard to measure product, and is just less exotic than making capsules, so I'm trying to find an efficient way to extract from the leftovers I have. Of course, dissolving the whole thing in ethanol would be safe and easy, but it costs about 40$/L where I live, so I'm thinking of using Methanol, which instead costs about 5$/L.

I know the byproducts of it's metabolism cause eye nerve damage, so I'm concerned about how to use it. My bet is that in a hypothetic scenario in which I had 200g of herb, I could dissolve the whole thing in 1L Methanol, let it dissolve for a couple of days (maybe even heat it?), then allow for open air evaporation, dissolve the product in 50 mL Ethanol, and then heat up in the controlled setup I use for decarboxylation, until all the ethanol is gone, and then a little bit more until decarboxylation is achieved.

This way I think I would get a pretty dark bad-looking goo full of chlorophyll, but since it would be used exclusively for orals I don't care about that right? If I'm not mistaken, evaporating the Ethanol at high temps (about 120C) would surely purge away the methanol completely, leaving me with a clean decarboxylated product.

Please I would love to hear your opinions. Is my reasoning flawed somehow? Will I cause irreversible eye nerve damage just by thinking about using methanol? Should I follow more like a QWET/QWISO protocol but just using Methanol instead of the usual solvents? Is the Ethanol step neccessary or I could just decarboxylate directly from the Methanol solution?

Thanks a lot! As always, icmag knows!

[SkyHighLer]

The FDA USP <467> Residual Guidelines place methanol in Class 2, and ethanol in Class 3. Decarbing the oil at 250F until the bubbling slows should ensure it's purged sufficiently of methanol.

https://hmc.usp.org/sites/default/fi...-Pdfs/c467.pdf


If you're interested in alternative solvents and their polarity and availability follow my Solvent Polarity list link in my Signature, and expand the thread.

[Biohpilic]

Thanks for the reply!

According to the link in your message, Acetone is also a Class 3 solvent. Would that be a suitable solvent for extraction? I guess it dissolving mainly water-solluble compounds doesn´t make it that great of an option does it?

And any tips on what procedure to follow for the extraction? quick wash or long soak?

Thanks!

[SkyHighLer]

Originally Posted by Biohpilic

Thanks for the reply!

According to the link in your message, Acetone is also a Class 3 solvent. Would that be a suitable solvent for extraction? I guess it dissolving mainly water-solluble compounds doesn´t make it that great of an option does it?

And any tips on what procedure to follow for the extraction? quick wash or long soak?

Thanks!

Acetone is readily available inexpensively, and has a very low boiling point, and high evaporation rate, but it's neither extremely polar or non-polar, so it's not the best for winterization or selectively discriminating against chlorophyll. Try a quick wash using chilled acetone.


Another solvent readily available inexpensively is ethyl acetate. Klean Strip's MEK Substitute is 100% ethyl acetate, you can get it at hardware stores except in California.

https://www.kleanstrip.com/uploads/d...B_SDS-1636.pdf

Or it's available online in any certified purity desired. Ethyl acetate and butyl acetate are the carrier solvents used in nail polish, the butyl slows the evaporation to prevent blushing. Nail polish remover is usually acetone at this time.

"Odor: ether-like, fruity
Boiling point: 77.1 °C (170.8 °F; 350.2 K)
The LD50 for rats is 5620 mg/kg, indicating low toxicity. Given that the chemical is naturally present in many organisms, there is little risk of toxicity."

https://en.wikipedia.org/wiki/Ethyl_acetate

"Nail polish consists of a film-forming polymer dissolved in a volatile organic solvent. Nitrocellulose that is dissolved in butyl acetate or ethyl acetate is common."

"The most common remover is acetone. This can be harsh on skin and nails, and can also remove artificial nails made of acrylic or cured gel. A less harsh nail polish remover is ethyl acetate, which often also contains isopropyl alcohol. Ethyl acetate is usually the original solvent for nail polish itself.

Acetonitrile has been used as a nail polish remover, but it is more toxic and potentially carcinogenic. It has been banned in the European Economic Area for use in cosmetics since 17 March 2000."

https://en.wikipedia.org/wiki/Nail_polish

[OG Expressions]

Originally Posted by SkyHighLer

Acetone is readily available inexpensively, and has a very low boiling point, and high evaporation rate, but it's neither extremely polar or non-polar, so it's not the best for winterization or selectively discriminating against chlorophyll. Try a quick wash with chilled acetone.

I agreen with you on acetone.

When the OP mentioned heating methanol it made me shiver. Ive seen that shit burn, the last thing i would do is heat it.

Its usually locked up outside in the cold in the winter here in canada. Its used in the window wash buckets at gas stations the pails have big warnings that say, leave locked in outdoor cage when cold or refrigerate

[troutman]

Methanol evaporates easy and is very easy to purge as they call it.
Just make sure you do this away from any and all flame sources.
Methanol burns very clean and the flame is almost invisible so be careful.

[Biohpilic]

Thanks people!

In the end I used the Methanol, I was interested in seeing how it worked because I like EtOH a lot and MetOH is a looot cheaper. Maybe next time I'll give a try to the acetone.

@OG Expressions Thanks for your advice, I treated it more like it was Ethanol than Butane. I worked inside, but I never got close to an open flame having more than 50mL of Methanol, and generally speaking I usually heat anything flamable by heating first an oil bath and then take it on and off the stove to obtain the desired temp (not heating it with the flamable stuff inside, of course).

Well, as I predicted, I got back a black unappealing slurry, and also I messed it up with the filtering and took the poor decision of filtering the last bits of plant material when the liquid had lost volume already, so I guess I lost a good bit of it. It's now filtering and I will proceed soon to decarboxylation (of course I'll probably mess that up too and burn the goods).

Again, thanks a lot people!, I'll finish processing it and I'll let you know how it went.

[OG Expressions]

Originally Posted by Biohpilic

Thanks people!

In the end I used the Methanol, I was interested in seeing how it worked because I like EtOH a lot and MetOH is a looot cheaper. Maybe next time I'll give a try to the acetone.

@OG Expressions Thanks for your advice, I treated it more like it was Ethanol than Butane. I worked inside, but I never got close to an open flame having more than 50mL of Methanol, and generally speaking I usually heat anything flamable by heating first an oil bath and then take it on and off the stove to obtain the desired temp (not heating it with the flamable stuff inside, of course).

Well, as I predicted, I got back a black unappealing slurry, and also I messed it up with the filtering and took the poor decision of filtering the last bits of plant material when the liquid had lost volume already, so I guess I lost a good bit of it. It's now filtering and I will proceed soon to decarboxylation (of course I'll probably mess that up too and burn the goods).

Again, thanks a lot people!, I'll finish processing it and I'll let you know how it went.

Theres folks around here with much more chemistry knowledge than myself, but i thought it wise to speak a word of caution. Methanol is scary shit, if it lights you womt even see the flames but whatevers on fire will feel it. I suspect if a person was caught on fire with it they would die in less than a minute or two, i see the survivability being on the rather low side anyway.

I remember seeing a drop of it lit inside a 5 gal jug in school, the vapor built up, and when they lit it the flame out the top was white we could only see it in the room because it was dark. It blew the ceiling tiles into the roof actually splitting one. It always freaks me out to be near it.

Ive often wondered why criminals disposing of evidence dont use the shit to light whatever on fire. Probably not much going that would be worth a pinch of shit as evidence after being lit with that stuff...

[Gray Wolf]

Originally Posted by Biohpilic

Thanks people!

In the end I used the Methanol, I was interested in seeing how it worked because I like EtOH a lot and MetOH is a looot cheaper. Maybe next time I'll give a try to the acetone.

@OG Expressions Thanks for your advice, I treated it more like it was Ethanol than Butane. I worked inside, but I never got close to an open flame having more than 50mL of Methanol, and generally speaking I usually heat anything flamable by heating first an oil bath and then take it on and off the stove to obtain the desired temp (not heating it with the flamable stuff inside, of course).

Well, as I predicted, I got back a black unappealing slurry, and also I messed it up with the filtering and took the poor decision of filtering the last bits of plant material when the liquid had lost volume already, so I guess I lost a good bit of it. It's now filtering and I will proceed soon to decarboxylation (of course I'll probably mess that up too and burn the goods).

Again, thanks a lot people!, I'll finish processing it and I'll let you know how it went.

Methanol is more polar than ethanol or iso, so goes for the chlorophyll. If you extract at -50C, it does a fine job.

It is more toxic than either ethanol or propanol-2 (iso), so purging is important. As a Class II solvent, the FDA standards are:

Solvents in Class 2 (Table 2) should be limited in pharmaceutical products because of their inherent toxicity. PDEs are given to the nearest 0.1 mg/day, and concentrations are given to the nearest 10 ppm. The stated values do not reflect the necessary analytical precision of determination. Precision should be determined as part of the validation of the method.

[G.O. Joe]

Methanol, ethanol, IPA, acetone, all very easy to purge. Get most of it out, then dissolve in pentane. Wash with water 3-4 times in the sep funnel. Water solubles go. Reclaim pentane by distillation and purge the last.