Hey everyone,

I recently did my first two attempts on the CIELO TEK and used up all my ethyl acetate. I know wanted to wash it to perform another extraction.

I followed the TEK instructions and washed it with 1/5 volume saturated sodium carbonate water.

Some questions came up during this process. It is mentioned that I can check the pH to verify the success of the wash. What pH am I aiming for? I am currently somewhere around 6. Is this too acidic and should I do another wash?

The separated water layer has some precipitate in it. I did two separate washes. One was frozen and then decanted through a coffee filter. The water looks slimy and has some sort of needle like crystals in it. Is this left over carbonate/citrate?
The second wash was not frozen and the water layer is clear but with lots of crystal precipitate looking like citric acid. Is this normal?

Also my washed ethyl acetate has become very cloudy and I can't see through it at all. I tried filtering through a coffee filter but nothing gets filtered out. It does not seem like I could reuse that ethyl acetate for another extraction. Should I do more washes?

Thanks for any help.

How are you measuring pH? If using a pH strip it should not change color. If it is acidic, need to wash more until it does not change (shake well).

I've noticed the cloudy washes as well. Should clear up with time. Interestingly, if you was with not saturated sodium carb (eg ~10%) at the end it clears up quickly. Something about saturated carbonate makes it stay cloudy longer for some reason (at least for me). See if it works for you also and I'll update the TEK.

IDK what xtlas you are seeing. Probably sodium citrate?

I have reused the same solvent many times. Gets dark but works fine. No changes in yield and the final crystals are as white as ever . Still need some level of fresh EA to replenish volume losses and do product rinses.

Thanks for your reply.



Yes I am using pH strips. The color is not really changing. Maybe a little bit.I might do another wash just to be sure.



Good to know. I will try that and report back.


I added more water and they dissolved directly. Maybe it was just saturated and that's why it precipitated. The water was still very basic but I assume any citric acid will be overpowered by the sodium carbonated water.

Yep, we are using excess sodium carb to completely neutralize the solvent.

You can compare the pH strip to fresh EA. There should be no difference after the wash. Before the wash there will be a clear difference.

I finally tried the 10% wash. After having the cloudy EA sit over a week it did not clear up but a sediment formed. After washing with 10% sodium carb water it cleared up over night.
Thank you again for the advice.

Thank you for the valuable update/data. Will update the TEK since this curious effect is confirmed.

How are your mescaline citrate xtals looking?

Maybe saturated sodium carbonate is still losing a bit of water to the EA? And this leads to solid sodium carbonate particles forming at the aqua/EA interface? The particles seem to be soluble so that was all of I could think of at first - but it doesn't seem to make that much sense for the saturated solution to lose water to the EA.

Another possibility is that it's sodium citrate refusing to dissolve in the saturated sodium carbonate solution due to the common-ion effect. There's just too much sodium in the aqueous phase already, so the citrate cannot dissolve - at least, not very much. Once the solubility product of the sodium citrate has been exceeded, whatever is formed will remain in solid form [notwithstanding the likely vanishingly tiny amount that will dissolve in the EA].

And without looking anything up, I'll confidently state that the solubility of any of the possible sodium citrates in water is significantly lower than that of sodium carbonate. Given the fact that there is a large excess of sodium carbonate compared with the amount of residual citric acid, I'd happily wager that the clouding is trisodium citrate.

Interestingly after putting it in the freezing to remove any water it clouded again. I will wash again to clear it up and then just separate the layers with a seperatory funnel and dry it with KCO3. Or is drying even necessary as it will come in contact with water in the paste anyways?

My Xtals look very nice. I am really happy with the outcome and getting them out of the goo. Hopefully I will manage to do another extraction this weekend to see if I can do it without getting goo.

Is the chilled solvent still cloudy after you filter out the slush, cover, and return to room temperature? If not, you are good to go. Drying woth K2CO3 is overkill as it will get wet again with the paste.

Going back to your original post/issues, I recomend you rest the exgract in the fridge for 24h or more until not cloudy. Decant, allow to get to room temp, and salt with 5g of citric per 100g of powder.

I never tested 35C EA extraction. At that temp, a lot of watee from the paste may be absorbed, so a good rest in the fridge to crash it out may be very important. I would not be surprised if you got a layer of gunk during this resting step. Please report back, you may have hard data to explain goo formation.

I also have the feeling that a lot of water gets absorbed due to the high temperatures. After freezing it I have a lot of ice in it. I filter everything through a coffe filter and discard the ice. Once the EA is back at room temperature it is very cloudy with sediment.

I did another wash with ~10% sodium carbonate and it is clear again. I will just use the separatory funnel to seperate this time.

I will most probably try another extraction this weekend and will definitely let it sit in the fridge this time. It is not 35°C anymore but still around 30. I will report afterwards.

Is there a reason you suggest letting it warm up again after the fridge rest or could I also salt the cold extract?

I was thinking let it warm just to make sure any water is well dissolved in EA before salting.

I believe Merking salts while cold and gets xtals though.

I did another extraction on 25g powder yesterday. It has been sitting in the fridge for ~18h. I will wait until full 24h. It was around 30°C when I did the extraction.

I will separate the EA I have into two parts and salt one directly and let the other one come back to room temperature first. Just to see if it makes a difference.

If you have any other suggestions that I could try I am happy to do so. Maybe trying to dry it further with K2CO3. However, I think I read in the original ethyl acetate approach that it has been tried and deemed unnecessary.

True, but we were not getting goo. I would try to xtalize 1/3 at room temperature and save the rest for trouble shooting.

Do you have pH paper to check the extract before salting?

Thanks for the advice. I will split it in three. I want to try salting the cold and the warmed up. Then in case both turn to goo I will try drying the last third.

I have pH paper and will check the pH before salting. What pH would be ideal? Basic in general or a specific pH?

Should be mildly basic. Here is what it looked like for my particular pH paper (around 8 ).

Also, did any water dropplets form in the EA after being in the fridge?

Yes and quite a lot. The walls have small drops sticking to it. And some even pooled on the bottom. I will have to be careful when decanting it.

This might very well be the reason I got goo before!

I will still wait until full 24h before going to the next step. I am nervous and excited to see how it turns out.

You may need to leave a few ml of EA behind with the water when decanting. I don't worry about that, any losses are minimal.

You can use the drags for your next extraction and not fuss with them.

Good advice. I will do that. Thank you again.

24h are over. I filtered the cold EA through a coffee filter. And then distributed 3 equal parts into 3 same sized smaller jars. All 3 look dark green but are see through. The pH is around 8-8.5.

I checked for water droplets but they seem to have stuck to the walls or coffee filter. I kept a small bit like you recommended to be sure.

The jar which was filled first should have the lowest possibility to have water droplets in case I oversaw them. I salted it while cold with an equivalent of ~6g anhydrous citric acid per 100g powder. I immediately saw clouding. Most of the citric acid dissolved after a few swirls and it stays cloudy now. I put it in the cupboard to rest now.

I will wait until the other jars get to room temperature, currently 27 °C. Then I will salt one more with the same amount of anhydrous citric acid and compare both jars tomorrow and report what I see.

The third jar will be kept in case I want to try drying with K2CO3.

Update: 30min have passed and I see crystals forming already in the salted jar. They start growing all over the jar walls. I couldn't be happier right now