IPA extraction went wrong

[Trickster]

Nobody seems to notice questions posed in the SWIM's other topic so she decided to start a new one.

SWIM ran his continuous solid-liquid extractor for 5 hours and collected 250 ml of dark purple IPA

Before the extraction she added phos acid to the IPA until the pH fell just below 3. After the extraction she decided to basify the IPA with lye. She added a teaspoon to the solution and soon noticed a thick black tar-like precipitate forming at the glass bottom.

She stirred it with an SS spoon and noticed that there are lots of small dirty-white chrystals embedded in the black tar (see pic.1). Her guess is that those were chrystals of lye that would not dissolve in IPA. Testing the solution pH confirmed her theory. It was just above 3. So she proceeded to dissolve a few teaspoons of lye in 50 ml of water and add it to the solution.

There was a reaction in the solution and soon it started to separate into 3 layers. Upper layer was dirty green. Middle was white, looking like emulsion and the bottom one was black (pic 2). First they were more or less equal in thickness and later the bottom one got thinner and the middle one almost disappeared. Then SWIM decided to stir the solution and see what happens.

In a few minutes the whole solution became black and thick (pic 3). It was so thick that it could not be stirred with a stirrer, so 60 ml water were added. Seeing that the solution closely resembled basified solution from an A/B extraction SWIM added to it 25 ml of heptane. Only later she has found out that IPA is lighter than heptane and will not float.

So now she's got her solution separated into 2 layers (pic 4). The top one is clear tea color IPA. The bottom dark opaque one with heptane trapped somwhere down there. Black flakes are parts of the bottom layer that got stuck to the glass walls.

Are there any idea how to get the spice from this mess?

Is it possible?

 

[Infundibulum]

It all makes sense;

IPA and water are miscible, but they separate in two phases when the ionic strength increases. Tell SWIY to try this. Mix 50/50 IPA with watern then dissolve some salt in it. After a while two phases will separate, the upper containing IPA, water and traces of the salt, and the lower containing mostly water, some IPA and salt. Some of the salt will crystallise out of the IPA/water mixture upon separation and may form a sediment or a crystalline phase on the interphase of the separated IPA::water mixture. Same happens with water/acetone mixtures.

Please play with it using just IPA, water and sodium chloride just to get a feeling of the situation.

The same thing happened in SWIY's case; SWIY added water of high ionic strength (NaOH in this case), then IPA separated from the water (it also contains loads of water so it is not a clean separation and not much of use). So now SWIY has one upper phase (mostly IPA), a bottom phase (mostly water) and maybe an emulsion in the middle containing some crashed out lye?

Advice to SWIY is evaporate the bloody IPA then play with WATER ONLY! (or minimal IPA present) ======> this is far safer and proven to work.

Hope this helps,

Nobody seems to notice questions posed in the SWIM's other topic so she decided to start a new one.

I do not like this phrase one bit. Patience is a virtue. I hope SWIY is not after quick answers to all questions! Sometimes it take agess to find the right answer from teh right person irrespective of starting new threads or not.

 

[endlessness]

what about the heptane added to make things a bit more complicated ?

 

[Infundibulum]

what about the heptane added to make things a bit more complicated ?

Urine, cornflower and broccoli soup are the proven combination to make the extraction truly complicated!!:d

 

[Trickster]

Thanks, Infundibulum,

It all makes sense;

IPA and water are miscible, but they separate in two phases when the ionic strength increases. Tell SWIY to try this. Mix 50/50 IPA with watern then dissolve some salt in it. After a while two phases will separate, the upper containing IPA, water and traces of the salt, and the lower containing mostly water, some IPA and salt. Some of the salt will crystallise out of the IPA/water mixture upon separation and may form a sediment or a crystalline phase on the interphase of the separated IPA::water mixture. Same happens with water/acetone mixtures.

Please play with it using just IPA, water and sodium chloride just to get a feeling of the situation.

I know she loves chemistry. She will for sure.

The same thing happened in SWIY's case; SWIY added water of high ionic strength (NaOH in this case), then IPA separated from the water (it also contains loads of water so it is not a clean separation and not much of use). So now SWIY has one upper phase (mostly IPA), a bottom phase (mostly water) and maybe an emulsion in the middle containing some crashed out lye?

Advice to SWIY is evaporate the bloody IPA then play with WATER ONLY! (or minimal IPA present) ======> this is far safer and proven to work.

Why not tell her to separate and discard the upper level (mostly IPA) with a sep funnel? Is not that faster and not so smelly? Or do you think that there may be a significant amount of Mr. В, Btw, is it in FB form?

Hope this helps,

It sure does!

 

[Trickster]

what about the heptane added to make things a bit more complicated ?

Yeah, that's right. Where is it? It is nowhere to be seen.

Probably it doesn't matter. It will be evapped right after the IPA.

Anyway, even if this extraction is not salvageable SWIM is glad that her little CSLE proved to be quite efficient.

 

[Infundibulum]

The same thing happened in SWIY's case; SWIY added water of high ionic strength (NaOH in this case), then IPA separated from the water (it also contains loads of water so it is not a clean separation and not much of use). So now SWIY has one upper phase (mostly IPA), a bottom phase (mostly water) and maybe an emulsion in the middle containing some crashed out lye?

Advice to SWIY is evaporate the bloody IPA then play with WATER ONLY! (or minimal IPA present) ======> this is far safer and proven to work.

Why not tell her to separate and discard the upper level (mostly IPA) with a sep funnel? Is not that faster and not so smelly? Or do you think that there may be a significant amount of Mr. В, Btw, is it in FB form?

eeeek!

Yes, the good stuff is in freebase form now and dissolved in IPA, just as loads of other oily, fatty and whatnot impurities. So no, do not discard the IPA. Maybe separate the IPA out, then dry it totally with a good amount of magnesium sulfate and then evaporate? And then use naphtha to crystallise the spice out of the evaporated, dried IPA goo?

It's up to SWIY; if she knows her chemistry then she knows what is more suitable for her:wink:

Thanks, Infundibulum,

You're welcome.

 

[Trickster]

It's up to SWIY; if she knows her chemistry then she knows what is more suitable for her:wink:

Well, I am afraid this is the case when loving is not necessarily knowing. Chemistry is her recently found love. Her first love were all things electric.

 

[Trickster]

SWIM did not bother to freeze precip the spice because she did not expect to get much. Every time she reduced heptane there appeared some dark yellow sediment. There was no usual clouding of DMT-supersaturated heptane. Every time SWIM filtered the sediment and continued reducing soon there was more sediment (see pic. 1).

She left heptane to evap and in a day there were probably 50 mg of dirty-yellow chrystals. SWIM decided to combine them with the next extraction.

This next time 50 g of mhrb were extracted with CSLE in 3 hours. By the end of this time mhrb lost all of its color and IPA in the extractor became clear.

In 2 more hours most of the IPA was distilled. At the bottom of the flask there were around 60 ml of thick red wine colored liquid. See pic.2.

Before proceeding SWIM re-read all Soxhlet-related threads. She should have done that earlire. Anyway here are the mistakes she made:

1. She used 99% IPA instead of 91%. Well, maybe it was less than 99% because she added some diluted phos acid.
2. Too much acid was added to the solvent (pH~2.2). She used 85% phos. acid diluted with water very approx 1/5.

Remembering how much gunk was extracted during the previous attempt she decided to do a defat with heptane before basification. To make the defat more efficient it was decided to raise the solution pH to at least 6.

So SWIM dissolved some lye in water and started to add it to the solution checking its pH from time to time. When she got to 4 she noticed that some light yellow flakes appeared in the solution. At pH 4.3 she stopped not sure what is going on. See pic. 3.

Please help SWIM. She is not sure what is in the flakes that precipitated to the bottom. Are those DMT phosphates that crashed out at higher pH, or some useless stuff to be discarded? With time it gets packed at the bottom.

 

[Trickster]

Here is what SWIM's done so far.

SWIM extracted 50 g of mhrb in her Continuous Solid Liquid Extractor with slightly acidified IPA. Most of the IPA has been distilled. Acidified water was added to the remaining extract. This solution has been defatted twice with heptane. Then the solution was basified to pH=12.6.

SWIM did 4 pulls with 20 ml of heptane each. All pulls were combined and left overnight in a glass at room temp. Originally heptane was the color of strong black tea and opaque. After 10 hours about 1/5th evaporated and fluffy precipitate started to form. The color of heptane is still dark yellow but it has become transparent.

Do you think this precipitate is spice? SWIM suspects it is not.

Which cleaning method is more adviseable at this stage?

1. Sodium carbonate wash.
2. Evap all heptane and do a mini-A/B.
3. Freeze-precip and do re-x.

 

[Trickster]

Finally, after careful decanting and filtering transparent yellow-reddish heptane was collected.

Unsure which route to follow, SWIM left it in a glass at room temp. Over 2 days nothing changed, only a brown oily ring appeared on the glass wall where some heptane evaporated.

SWIM decided to reduce heptane and started to pour it in a wide cup. Unexpectedly a large blob of jelly plopped from the glass into the cup. Its color is the same as heptane.

What is this jelly and what SWIM is supposed to do with it? Just to remind you steps so far. All chemicals are lab grade. By-products of all steps were saved.

1. SWIM extracted prepowdered mhrb with boiling 91% IPA in his CSLE.
2. The extract was diluted in acidified water (pH~3.3)
3. Defatted twice with heptane.
4. Basified with lye to pH=12.6
5. Pulled 4 times with heptane.
6. Decanted and filtered solid precipitates that fell to the bottom overnight.
7. Left the heptane sitting under room temp for 2 days and got a large transparent blob of jelly ~1/3 of total heptane volume.

Please, help.

 

[endlessness]

what about redissolving in small amounts of warm heptane and freezing?

 

[Trickster]

what about redissolving in small amounts of warm heptane and freezing?

It seems SWIM's been not too clear in her description.

She had 60 ml of heptane 1/3 of which was transparent jelly-like goo of the same color as heptane. Way too much for freeze-precipitating. Now she has slowly reduced the heptane volume to just under 20 ml. That is 1/4th of the original combined 4 heptane pulls volume.

Its color is of strong black tea and it consistency is like a thick syrup.

What would you recommend to do next?

1. To freeze-precip the syrup.
2. To evap completely and do a mini A/B extraction.

 

[endlessness]

In that case I do think a mini A/B might be a good idea indeed.

keep reporting back!

 

[Trickster]

In that case I do think a mini A/B might be a good idea indeed.

keep reporting back!

Today SWIM did not have much time to do a mini A/B, so, out of curiosity, she put the brown jelly in a freezer. In 12 hours there are beautiful white strafishes floating among white specks. The spice is there.

The starfishes and specks are impossible to separate from the jelly, so jelly will be evapped/redissolved in acidified water/basified, and so on.

 

[Trickster]

So SWIM evapped most of heptane from the jelly and redissolved solids in acidified water (dH2O + vinegar, pH ~2.8).

She vacuum filtered the solution and basified it to pH ~12.7 with lye. Unusually for SWIM, the basified solution was not black, but off-white. Then she did 4 heptane pulls and combined them. Now almost colorless heptane is waiting to be reduced for freeze-precipitation.

 

[endlessness]

sounds good to me! Curious about what turns out...

 

[Trickster]

sounds good to me! Curious about what turns out...

Today SWIM got 410 mg of very white, faint smelling beautiful spice (0.82%). It's her best ever.

Lessons learned:

- Do not despair and do not discard anything;
- Write a step-by-step journal;
- IPA is non-selective and pulls everything, therefore extracts require a lot of cleaning.

Thank you guys for all your assistance.

 

[endlessness]

Congrats! Nice that you learned from all the process and that it also turned good in the end