Hello!

I sadly have shit bark and if my pulls evaporate, I am left with brown stuff instead of white crystals, even though I use a Hexane/Pentane Naphtha and not even the Heptane one.

Recrystalisation is not s deal, because it has not been possible to separate the spice from that brownish shit by that so far.


My question:

Does the Fumarate PRECIPITATE in Acetone / IPA ?

Because I only read that if you mix Spice + Fumarate in Acetone / IPA you will have to evaporate it. Yes, the salt will be formed, but it sounds like it is not crashing out by its own or at least not in a quantitative way. Therefore it is mentioned to let the solvent evaporate to get your stuff.


If it WOULD crash out and not only partially, but the whole Fumarate-Salt, then I could just use this technique to purify it out of my dirty brown crystals, if everything is dissolved in Acetone / cold IPA.


So would this be possible?

fb=>fumarate
Yes, it precipitates, you don't have to (and shouldn't) evaporate anything. But everything has to by anhydrous...
I am not sure you will purify it much this way, to same degree maybe, but re-x from heptane is simply the best. Have you done that? How are you doing it that it doesn't work?

You may try mini a/b with hot heptane pulls for re-x for further purification. This way might give you good results. I am doing it even with perfect bark. You may check here

Ah well actually it was not correct what I told ... I recognize now.

Re-x was not tried on that stuff, I messed it up in my memories.

I re-x-ed with a Mixture of extremely low evapping Naphtha (Pentane / Hexane) and it's fine.
That very low boiling stuff has proven to dissolve even less impurities for me, that's why I have it.


But to that FB -> Fumarate, there is 1 additional question now:


I hear people talking about using excessive Fumaric Acid and then cleaning it off the Spice-Fumarate afterwards.

It is indeed needed to use excessive Fumaric Acid on the Spice ? Is there an Equilibrium somewhere in between and not totally towards the Spice-Fumarate salt ?

Because if not, then why doesn't everyone just add that 309 g Fumarate per g Spice ? (I dont remember the actual number, but this is what some people say and to me it sounds plausible just using this amount and not more).

if we talk about FASA, then yes, 309mg is enough for one gram of fb. Check here-Freebase DMT to DMT Fumarate.
I personally use about 10% fumaric acid more, just to be sure. Because so much of acetone is used, all excessive fumaric acid stays in the acetone. But it has to be decanted after precipitation, not evaporated. Otherwise fumaric acid would stay in the result and would have to be removed.

if we talked about salting with FASW, then it is not clear whether it is enough to add FASW just to get pH to 6-7. When I did and calculated how much freebase should be there, I was then missing 18% of estimated weight, which is signalling some kind of problem. Therefore I stopped using this technique.