Which Non polar solvent? - Naphtha (petroleum ether 100-120) or (40-60) 60-80 fractions) - for freeze-precipitating

[OccipitalBob]

Bonjour fellow space rangers and keepers of the faith, could someone tell me if my (Non polar solvent)
- Naphtha (petroleum ether 100-120) will work or will I need to use 40-60 or 60-80 fractions) - for freeze-precipitating from (finely shredded MHRB + Sodium Hydroxide)

And just incase I can save it (does the higher boiling point 100-120 petroleum ether make crystalline formation impossible?

Daft questions from a somewhat frustrated, yet undeterred kitchen chemist. my thanks for your patience in advance.

Occipital Bob

 

[Transform]

Hi, welcome - sorry your question appears to have gotten overlooked!

You should get decent enough results with the 100/120 stuff if it's low in aromatics, which would otherwise prevent freeze precipitation. The lower boiling stuff evaporates more quickly, which can be annoying under warmer conditions as well as having advantages for final purity.

As long as your solvent evaporates cleanly it'll be fine. I hope it's worked out for you!

[Dissolved freebase can be collected by using vinegar washes, yielding DMT acetate, if there's any reason freeze precipitation hasn't worked. This saves you from having to evaporate a whole volume of naphtha. It's easy enough to turn the acetate back to freebase too, should happen to go in this direction.]

 

[OccipitalBob]

Hey, thanks for the comprehensive reply.

I’ve performed some further due diligence since posting. The lower fractions will work better than the higher boiling point petroleum ether (100-120) ( it simply doesn’t produce any crystalline engineering when frozen well for me anyway.)

I’ve gone for 40-60, this whole conundrum came about due to Naptha vm&p not being commercially available locally, so you have to source the chemical equivalent (scientific grade solutions come in 3 different fractions of petroleum ether)

1. 40-60
2. 60-80
3.100-120

Freezing overnight, so fingers crossed I’ve nailed it this time

Unfortunately I got a little base in my glass dish, do you know of a tried and tested way to separate or wash. ( I will have a good read through the forums, this is just on the off chance you see this )

Warm regards

Occipital Bob

 

[Transform]

Unfortunately I got a little base in my glass dish, do you know of a tried and tested way to separate or wash. ( I will have a good read through the forums, this is just on the off chance you see this )

This is a common issue best prevented by transferring the naphtha from the base soup into a glass jug before passing it into the precipitation vessels. This will catch any stray droplets of aqueous base, and can be enhanced by including a small volume of saturated sodium carbonate solution in the intermediate jug, which also helps to wash the naphtha of these droplets.

If you have base contamination in your precipitated product you'll have to clean it up, either by recrystallisation from a minimum quantity of fresh naphtha or by putting it through a 'mini A/B', which is essentially a miniature acid-base extraction.

 

[OccipitalBob]

I’ve had a look this morning, it’s been in the freezer 15 hours, all I can see at the moment is tiny granular items floating in solution, really don’t want to throw this one away, does it need longer? I’m a little nervous of AB extraction, is there a step by step you could sign post? I’m 2 months trying to make things work it’s driving me crazy

 

[Transform]

If you don't want to mini A/B, just recrystallise using the 60-80 naphtha and a warm water bath. No naked flames! Slower cooling makes bigger crystals.

 

[OccipitalBob]

total life saver. again, my thanks for all the additional advice.

I think I might have gone too cold too soon perhaps and the crystals are tiny right now?

The overarching issue for most (i should imagine) is that comparability/standardisation of process is troublesome as there are a multiple variables that can go astray, and the result is subjective

The only quantifiable output seems to be weight and colour, do I leave it in the freezer for longer, I’ve got it 1cm deep in one dish and around 2 cm deep in the other (roughly 100ml and 150ml respectively) is this way to deep, will this increase freeze duration required.

Have been thinking about letting some of the naptha evaporate and putting them back in?

Any and all thoughts welcome ( that is of course if you have the time ) no umbrage taken in the event of no reply.

Warm regards

Occipital Bob

 

[Transform]

I just wrote up a mini A/B description in this post, but try not to tell anyone as it's meant to be an initiative test

 

[OccipitalBob]

Top banana, I will have a good read through.

Thanks

Occy Bob

 

[Transform]

I think I might have gone too cold too soon perhaps and the crystals are tiny right now?

There's a thing called "Ostwald ripening" - slow cycles of temperature change will cause the small crystals to dissolve before the large ones, so the small ones disappear and the larger ones grow larger still. You can either leave your dish in the freezer for a few more days and hope that the normal cycles of switching on and off take care of this, or swap it between the fridge and freezer a few times, best using an insulated container to slow the chilling phase.

If your dish is new, it may have too smooth an inner surface and thereby lack nucleation points, hence the floaters. You can remedy this if necessary by pouring out the naphtha and scratching the base of the dish a few times gently but firmly with a fork.

You'll probably want to avoid getting glass powder in your product, so make sure you've allowed the naphtha to drain off completely so you can rinse and dry your dish before bringing it back into use - or just wait until your next round of extraction comes up before applying this trick, if it even seems necessary.

 

[OccipitalBob]

Every day is a school day atm, that’s brilliant thankyou, will give it a go

 

[Icon]

I think I might have gone too cold too soon perhaps and the crystals are tiny right now?

Yea I believe that is correlated. "Supercooling" leads to super nucleation, aka many tiny growth points.

What temperature did you do the extraction at? 40-60 pet ether has a very low solubility for DMT at room temperature. This increases dramatically when warmed up near the boiling point. But if you extracted at room temp there may only be a small % of DMT in it to begin with. In my experience, after I have pulled with warm solvent, simply letting the decanted pulls cool down in the crystallizing dish overnight often leads to crystals at room temp, that stick to the glass. Then you can move it to the freezer to squeeze out the rest of it.

Have been thinking about letting some of the naptha evaporate and putting them back in?

The mini-A/B would be better for that. You can save your solvent by washing the DMT out with vinegar, then re-base and re-pull with a smaller, hotter volume of solvent.

 

[Transform]

What temperature did you do the extraction at? 40-60 pet ether has a very low solubility for DMT at room temperature. This increases dramatically when warmed up near the boiling point.

This is a good point. The lower boiling point really limits the amount of DMT in that grade of naphtha, which is why I'd suggest using the 60-80 stuff instead - you can simply warm it up that bit more and. The 40-60 pet ether also evaporates quickly enough to get rather annoying if you're try to work with it warm, such as during warm pulls from base soup, giving another point of advantage to using the 60-80.

 

[OccipitalBob]

Yea I believe that is correlated. "Supercooling" leads to super nucleation, aka many tiny growth points.

What temperature did you do the extraction at? 40-60 pet ether has a very low solubility for DMT at room temperature. This increases dramatically when warmed up near the boiling point. But if you extracted at room temp there may only be a small % of DMT in it to begin with. In my experience, when warming the pulling solvent up, if I let the pull sit in the crystal dish overnight, often crystals grow fine at room temp, and stick to the glass. Then you can move it to the freezer to squeeze out the rest of it.


The mini-A/B would be better for that. You can save your solvent by washing the DMT out with vinegar, then re-base and re-pull with a smaller, hotter volume of solvent.

Left it outside during the pull, and it’s quite cold (so probably a few degrees cooler than room temp)

So essentially, I have two glass dishes in the freezer with likely tiny amounts of DMT in solution (due to lower mobility at sub optimal temp)

Which (if any) sound like reasonable next steps?

A

1. Remove from freezer, allow to warm backup to room temperature.

2. Alternate between fridge and freezer to encourage larger crystal growth

3. Score the (new) glass container to encourage ( nucleation points for crystalline production )

B

1. Remove from freezer, allow to warm backup to room temperature

2. Add vinegar to each dish (presumably forming DMT Acetate. (Does the vinegar kick the DMT out of the solvent at room temperature? Do you then just pour off and leave to evaporate/ dry?

Many questions a few fails (4) and no wins yet, so grateful for the advice of those in the know @Transform @Icon.

Warm regards

Occy Bob

 

[Icon]

The 40-60 pet ether also evaporates quickly enough to get rather annoying if you're try to work with it warm, such as during warm pulls from base soup, giving another point of advantage to using the 60-80.

Ooph yea I've never extracted with 40-60 but I can see all the agitation rapidly evaporating it when warm. Should definitely go with 60-80 or even better 100-120 for warm extraction work.

The 40-60 should still be good for pulls off the mini-A/B that wouldn't need as much agitation.

 

[Transform]

Left it outside during the pull, and it’s quite cold (so probably a few degrees cooler than room temp)

So essentially, I have two glass dishes in the freezer with likely tiny amounts of DMT in solution (due to lower mobility at sub optimal temp)

Which (if any) sound like reasonable next steps?

A

1. Remove from freezer, allow to warm backup to room temperature.

2. Alternate between fridge and freezer to encourage larger crystal growth

3. Score the (new) glass container to encourage ( nucleation points for crystalline production )

B

1. Remove from freezer, allow to warm backup to room temperature

2. Add vinegar to each dish (presumably forming DMT Acetate. (Does the vinegar kick the DMT out of the solvent at room temperature? Do you then just pour off and leave to evaporate/ dry?

Many questions a few fails (4) and no wins yet, so grateful for the advice of those in the know @Transform @Icon.

Warm regards

Occy Bob

If you're willing to try the exercise, I'd say the A/B process would be the one to go for. However, the path of least resistance would be to combine the pulls and let them evaporate down to slight milkiness before putting them first into the fridge and then the freezer. This especially applies because you've used the 40-60 pet ether.

Do be aware of its fire and explosion hazard, though!

 

[OccipitalBob]

If you're willing to try the exercise, I'd say the A/B process would be the one to go for. However, the path of least resistance would be to combine the pulls and let them evaporate down to slight milkiness before putting them first into the fridge and then the freezer. This especially applies because you've used the 40-60 pet ether.

Do be aware of its fire and explosion hazard, though!

Aces all round, will try the A/B.


1 Remove frozen Naptha dish from freezer

2 Decant Naptha/DMT solution into jug containing diluted vinegar (stir or leave?)

3. ( leave the already frozen dishes to evaporate off any remains of Naptha) might be a few crystals there

4. Draw off the vinegar (discard or reuse Naptha) Q. how long does it take for the vinegar to draw out the DMT in the solvent?

5. Add base ( sodium hydroxide) to DMT acetate, thus increasing solution ph to kick it back out of acetate and into the new (warmer but not too warm- 40-60’ boiling point Naptha (standard 3 plus hours extraction?)

6. Start off cooling in fridge, then move to freezer

Hopefully this sounds kosha, Let me know if I’ve missed anything glaringly obvious.

I leave you with a quote (based loosely on the theme of safety)

Evel Knievel. Circa, December 2007

“Safety first, first aid second”

Warms regards

Occy Bob

 

[Transform]

A bit of stirring helps the DMT transfer into the vinegar - it's about maximising contact between the two phases. Transfer occurs rapidly at the interface, but diffusion within the aqueous phase would be rather slower if left undisturbed.

The naphtha can be reused virtually endlessly - if you really needed to you could even use it again for pulling back out of the aqueous phase after adding base, although it's probably better to use fresh naphtha for that.

Pulls from the basic solution needn't tape 3 hours, you can get them done in minutes if you manage to avoid emulsions. Emulsions should be fairly unlikely during a second A/B cycle like this anyhow.

 

[Icon]

1 Remove frozen Naptha dish from freezer

2 Decant Naptha/DMT solution into jug containing diluted vinegar (stir or leave?)

3. ( leave the already frozen dishes to evaporate off any remains of Naptha) might be a few crystals there

4. Draw off the vinegar (discard or reuse Naptha) Q. how long does it take for the vinegar to draw out the DMT in the solvent?

5. Add base ( sodium hydroxide) to DMT acetate, thus increasing solution ph to kick it back out of acetate and into the new (warmer but not too warm- 40-60’ boiling point Naptha (standard 3 plus hours extraction?)

6. Start off cooling in fridge, then move to freezer

First off, there might not be much DMT in the 40-60 right now if it was done cool.

Check this solubility curve for n-Heptane (a component of naphtha that boils at 98 C).

At 20 C, the solubility is around 4mg per g. 150ml of heptane is about 100g. So if your solvent was heptane, it might only pull 400mg in 150ml. Generally the lower the boiling point for pet ether, the less capacity for DMT. So in your case with 150ml of 40-60 pulled below room temp, there might be significantly less than 400mg to collect.

Back to your steps:
2) When you add vinegar it's called salting the (non-polar) solution, it should happen very quickly, but stir it for a minute or so to be safe, since the layers won't want to mix naturally.
3) if you don't see any precipitate already, the solvent residue isn't going to yield anything worth spending time on.
4) See 2)
5) After adding base you can pull right away and it won't take longer than mixing the two layers together again. 30 seconds maybe.

But since there might not be much DMT in those pulls, you might as well just skip the mini-a/b for now and warm the solvent up to do another pull at a higher solubility point. (you'll want to warm up the bark-soup too otherwise the 40-60 will cool down fast.) The low amount of DMT in there right now won't go anywhere, and will have a better chance to crash out if you saturate the solvent at a higher temp.

If you don't have a way to condense or ventilate the vapors coming off the hot solvent though, I wouldn't recommend it. You could wait to get 60-80 or 100-120 and save the lowest boiling stuff for purification. I guess you could do it outside in a hot water bath or something.

 

[OccipitalBob]

Zero crystallisation in the left over dish after 15 or so hours in the freezer, just a big old helping of disappointment (ffs)

I’ve done the wash, (odd residue in the centre of swirling vortex during stirring (siphoned off with pipet) 2nd A/B extraction, naptha DMT solution now sitting in a glass container in the fridge.

Allowed to evaporate a little more and I have disabled the door light mechanism (just encase there is build up of gaseous 40-60 Naptha I wanted to remove any ignition source

Scored the bottom of the glass to aid propagation ( container is extra tightly sealed with plastic and gaffa tape )

Gonna give it over night in the fridge then move it to the freezer, if this doesn’t work could anyone sign post me to a step by step that seems to chime well with newbie’s.

I’ve wasted so much material it’s starting to get to me 🫩