Soxhlet and Fine Powder

[Rivea]

Finally, swim's tek produced ~1% of beautiful fluffy crystals. After many trials and errors the tek has been reduced to the following steps:

1. Ethanol extraction in Continuous Solid-Liquid Extractor (a Soxhlet, or similar would do).
2. Distillation of Ethanol from the extract.
3. Drying the extract.
4. Dissolving the extract in acidic water (pH ~4.5-5)
5. Settling/decanting/filtering.
6. Defatting with Heptane/Hexane(optional).
7. Basifying with NaOH to ph ~11.5
8. Five Heptane/Hexane pulls.
9. Distillation of excessive Heptane/Hexane to ~20% of the original volume of combined pulls.
10. Freeze-precipitation of Spice.

The setup and tek proved to be very efficient chemicals-wise. Until now it has been tested in a few small scale extractions only (50g of mhrb).

You can judge the spice quality by the picture. White stains in the upper-right part of the photo are on the weighting cup and are not related to the spice.

Excellent work Trickster. I have switched my focus to sonication. I purchased a converter/horn and a 750 watt power supply for a very good price, but they were mismatched components.. After fooling around with it for a couple weeks to make the mismatched converter work with the supply I am able to get very high energy delivery to my samples.

The point is in this process I too have discovered with the help of Benzyme that elegance of not over acidifying my extractions. Using just 3 ml of 8% vinegar in ~500 ml of water to process 100 grams of MHRB I sonicted for about 1 hour (1/2 hour per 250 ml), I did gross filtering and decanting, and then basified to about pH = 13 using 5 grams of NaOH. It is good to conserve chemicals.. I could have used a lot less lye. I got a modest yield of about 0.6% using Pentane/Hexane PE doing several (8) pulls in my separation funnel. The result was my usual snow white powder.

 

[Trickster]

Thanks for your comments.

... I have switched my focus to sonication. I purchased a converter/horn and a 750 watt power supply for a very good price, but they were mismatched components.. After fooling around with it for a couple weeks to make the mismatched converter work with the supply I am able to get very high energy delivery to my samples.

I believe your findigs are well worth a separate thread.

I did try to follow this route too, but could not find a decent generator/transducer combo for a reasonable amount of money. So, the idea is on hold for some time.

On the other hand, if we put aside our love for pure experimentation, either sonication, or sophisticated extraction devices are only useful if they produce cheaper and cleaner end product.

I thought of this and tried to justify my experimentation from this point of view. I'm still wokring on it.

The point is in this process I too have discovered with the help of Benzyme that elegance of not over acidifying my extractions. Using just 3 ml of 8% vinegar in ~500 ml of water to process 100 grams of MHRB I sonicted for about 1 hour (1/2 hour per 250 ml), I did gross filtering and decanting, and then basified to about pH = 13 using 5 grams of NaOH.

Don't you think it's too high? I am getting comparable yields raising my pH to only 10.6.

Then I've risen my pH to 11.5 and got another 0.5%. After that I took it to ~12.5 and got another 0.3%.

After freeze-precip resulting products did not look exactly like the product from the first batch (less fluffy and needle-like crystals. more like white powder). I did not check its potency separately, so I am not sure it was pure DMT.

I got a modest yield of about 0.6% using Pentane/Hexane PE doing several (8) pulls in my separation funnel. The result was my usual snow white powder.

We may have mhrb of significantly different potency, or maybe I am extracting some inactive alks, but if I apply pH range 4.5 to 12, my yield is more than 1%. I do 5 Heptane or Hexane pulls (each pull is ~20% of the volume of the basic aqueous solution). Later I distill the solvent until my combined pulls are 1/5th of the original volume. Is there any special reason you're using Pentane/Hexane?

 

[Rivea]

Sonication does deserve a separate thread and I apologize for somewhat hijacking your thread.

My point about posting what I did was more to commend you for doing a great job with your extractor tek particularly in that requires less chemicals when you don't start off using too much acid in extractions.

I overshot the pH mark in my extraction using minimal chemicals. This was because I poured too much NaOH solution too quickly. I actually used low boiling point PE not knowing any better. It boils at 35 deg C so it has to be largely pentane or some hexane isomer.

As for the economic practicality of sonication I have to agree with you there. I wanted to experiment with sonication and cost to a certain point was not a limiting factor for me. I got into it purely because of my curiosity around the technique and not because it was economically any advantage. I also was willing to risk and do some real detailed electronic troubleshooting to make my mismatched setup work... but that definitely is another thread.

 

[Shaolin]

Using just 3 ml of 8% vinegar in ~500 ml of water

Don't want to be a playa hater but isn't this still a relatively low pH (3.4 with my calculations*) ?

I also agree with Trickster about the upper pH. 10.6 should be plenty.

*
8%= 0.08
0.08*3 = 0.24
0.24 with 500ml of H2O.

Trickster:

How (amounts of acid) do you get your pH to 5 ? I think this has a simple answer but I don't know it at the moment, hehe.

Have you maybe compared the %yield of different pulls ? Any special reason you choose heptan/hexan over DCM ?

I'll post a new thread about this soon but anything greatly over ~1% is well, fishy.

Anyway great work both of you. Soxhlet is the now and sonication is the future.

 

[Trickster]

Sonication does deserve a separate thread and I apologize for somewhat hijacking your thread.

I was pleasantly surprised somebody followed this route. I was planning to do that myself, but could not find proper equipment.

I have many questions and would love to discuss it.

I overshot the pH mark in my extraction using minimal chemicals. This was because I poured too much NaOH solution too quickly.

Sounds familiar.

I actually used low boiling point PE not knowing any better. It boils at 35 deg C so it has to be largely pentane or some hexane isomer.

I did not experiment with anything boiling lower than hexane, yet. I use n-hexane (b.p. 68.7C). It is much easier to distill or evap than heptane, but I suspect it dissolves DMT somewhat better than heptane. There's been more spice after evaporation of hexane remaining after freeze-precipitaion than in case of heptane.

As for the economic practicality of sonication I have to agree with you there. I wanted to experiment with sonication and cost to a certain point was not a limiting factor for me. I got into it purely because of my curiosity around the technique and not because it was economically any advantage. I also was willing to risk and do some real detailed electronic troubleshooting to make my mismatched setup work... but that definitely is another thread.

I know what you mean. Actually that was more a reminder to myself.

Currently I am looking for an inexpensive Rotavap that is very useful for all sorts of extractions. I saw a nice one for $800 at a local lab supply exhibition and I've found it in China for $650, shipping included.

 

[Trickster]

... How (amounts of acid) do you get your pH to 5 ? I think this has a simple answer but I don't know it at the moment, hehe.

I do not do any calcultaions. At the beginning I dilute my dried alcohol extract in distilled water and check its pH. Then I simply watch my pH while adding DILUTED acetic acid dropwise until I get to pH=5.

Have you maybe compared the %yield of different pulls ?

No. 5 pulls seems enough. With some experience I do them quite quickly. Actually less than in an hour. Although it is a good idea to check. Maybe 5 are too many.

Any special reason you choose heptan/hexan over DCM ?

2 reasons:

- No access to good quality DCM.
- Hexane/heptane works fine as extraction solvent and as freeze-precip/re-x solvent, while DCM is great for extraction only.

Now, as I finally got some reagent grade DCM, the next step would be to try the following:

1. Mhrb alcohol extraction in a Soxhlet.
2. Distilling alcohol and drying the extract.
3. A/B cycle (pH 5 - 11)
4. DCM extraction
5. Distilling DCM and drying the extract.
6. Re-xing the extract from Heptane/hexane.

 

[Shaolin]

I'm purely speculating but indeed five might be an overkill and as for DCM two would probably be just fine although I would love to see a quantitative test.

As for further experiments, defatting (although I'm not sure if this is even needed with Soxhlet and with MHRB) with DCM, although one must use citric acid, since citric salts are, according to 69ron insoluble in DCM.

Oh, I wish we lived in a GS/MC-analysis-in-WalMart-for-20$ world.

Looking forward to this experiment, it should bring top quality n,n DMT.

 

[Trickster]

I plan another interesting experiment.

1. After alcohol extraction do an A/B using as narrow pH range as seems reasonable, i.e. DMT pKa +-2, (6.86 to 10.86). Save the extracted solution. Check yield and product quality.
2. Do another A/B cycle on the saved solution applying wider pH range e.g. 5 to 11.5. Save the extracted solution. Check yield and product quality.
3. "===//===" 4 to 12.5. Save the extracted solution. Check yield and product quality.
4. "===//===" 3 to 13. Save the extracted solution. Check yield and product quality.

The toughest part of the experiment is to test the product quality reliably and objectively.

Melting point measurement looks like an affordable alternative to GS/MC-analysis, but lab equipment for it still costs a few thousand USD. Nobody seems to be using Thiele tubes anymore.

 

[benzyme]

swim got a thomas hoover unimelt for $56.
(not to mention a complete rotovap for $450)

just gotta keep your eyes peeled


GC/MS is all fun and good, but SWIM prefers to use LC/MS. it has a wider range of compounds it can test for, particularly heat-labile compounds.

 

[Shaolin]

swim got a thomas hoover unimelt for $56.
(not to mention a complete rotovap for $450)

Mad auction game yo.

 

[Rivea]

I've been keeping my eyes peeled for the uni-melt. I saw one cheap, but it was missing the thermometer tower. Did you get everything with yours for the $56 Benzyme?

 

[benzyme]

everything except the thermometer

 

[Trickster]

So, after many trials and errors here is my best Soxhlet or CSLE tek.

1. Soxhlet alcohol extraction (methanol and ethanol seem to be better than IPA).
2. Distilling and drying the alcohol as much as possible.
3. Dissolution of the extract in diluted phosphoric acid (pH ~4.5).
4. Settling/decanting/filtering the acidic solution.
5. Basifying to pH ~11.5 by adding diluted NaOH drop-wise and checking pH regularly.
6. 6-7 small Heptane/Hexane pulls. Prior to pouring the mixture into a sep funnel I stir it for 10-15 min with a mag stirrer/hotplate on "low" and temp set on 50 C. I prefer Hexane because of its lower b.p.
7. Reduction of NPS until it becomes cloudy. Usually to 1/3rd - 1/5th of the original volume.
8. Slow cooling of hermetically sealed freeze-precipitation beaker. 2 hrs at room temp + 4 hrs in a fridge + 8 hrs in a freezer.

The procedure has been tested several times and it consistently produces ~1% yield. The product looks white and crystalline. No MP test yet, but bioassay results are very positive. 3 different persons were launched into hyperspace using 30 mg each.

Advantages:
- efficiency (most of alcohol and NPS could be recovered),
- consistency,
- high yield,
- eco-friendly,
- good quality product (no need to re-x).

Disadvantages:
- requires some special lab equipment,
- requires certain minimal skills.

P.S. Attached is the product photo. These 850 mg were extracted from 70 g of year-old brazilian mhrb.

 

[Shaolin]

Well the use of DCM would minimize the amount of pulls but you would extract a wide spectrum of alkaloids, which would mean the need for re-X.

 

[benzyme]

requires much less energy though, because dcm doesn't require heating.

the hexane or heptane would need to be heated to dissolve the residue, which could then be freeze precipitated. one could do a full extraction, up to the free precip part, in about an hour.

i've messed with soxhlets several times back in the day, it's just too tedious

 

[Shaolin]

I actually wanted to mentioned the heating point

Well it all comes down to how selective heptane/hexane is in this mixture of wide spectrum alkaloids (and stuff).

 

[Trickster]

Well the use of DCM would minimize the amount of pulls but you would extract a wide spectrum of alkaloids, which would mean the need for re-X.

It seems that the use of DCM for mhrb extraction is unwarranted.

Recent results also show that for smaller pulls - around 20 ml of Hexane per pull - their number should be at least 7 or more.

First 6 pulls yielded 570 mg only. 2 more 40 ml pulls added another 280 mg. During the last pulls I heated the mix to ~50C and stirred it with a mag stirrer for 15 min.

I am not sure if I should distill Heptane/Hexane because I suspect that some product will evaporate as well. I have found a decent Rotovap in China for ~400 USD. Would be a great Christmas present .

 

[Trickster]

... one could do a full extraction, up to the free precip part, in about an hour.

Interesting. Do you mean using DCM as the first solvent? Is it polar enough to extract the spice salts from the bark?

i've messed with soxhlets several times back in the day, it's just too tedious

I understand. After a decade of radio engineering I would also be bored experimenting with a basic radio. But in chemistry I find experimentaion very exciting. Maybe because it is new to me.

 

[Shaolin]

Unwarranted as in, not being selective, alkaloid wise ?

I'm not convinced about the need for some many pulls. I think you should monitor invidually. Could be that the first pull yield 450, the second one 100, and the other four 20 total.

A friend said "So, small engine, Shop vacuum, crock pot, pulley, glass blowers air tight swivel(can be made at the hardware store), tubing, a condenser, or cold sink to reclaim your solvent. "

 

[benzyme]

understood.

DCM can't unbind the alkaloids from intracellular macromolecules, that is, it doesn't hydrolyze DMT from other intracellular molecules.
it'll solvate just about everything, but we use acids and bases to hydrolyze bonds, separating the molecular complexes. it's been speculated that DMT is in the tannate form in vivo .
we use DCM once the dmt has been hydrolyzed from the tannins