I honestly think water is an undervalued solvent around here

Starting material was 500 mg of brownish ACRB fumarates. Freebase was extracted with naptha (no defat or mini-AB) and then converted to fumarate by dissolving in FASW, evapping and removing most excess fumaric acid by dissolving in 12 ml of water per gram and and filtering, evapping and repeating a couple of times (described here).

The 500 mg fumarates was dissolved in ~25 ml water and ~250 mg of activated charcoal powder was added (maybe overkill, I dunno). This was left to settle and then filtered through a cotton ball stuck in a syringe. The activated charcoal managed to tear up the rubber plunger in the syringe pretty bad. The filtered water was evaporated in a pyrex dish to to yield ~390 mg total of clear crystal shards, some slightly off-white hard fumarates, and some goo around the edges that IME will probably harden over time.

I don't know if there were actually 110 mg of impurities in the starting material, but I'm assuming the charcoal also sucked up some of the alkaloids. Anyway I have a lot of this stuff so I'll probably clean some more and try to evaporate more slowly for prettier crystals. This evaporation took only a couple of hours in front of a fan.

Photos of starting material and evaporation dish:

good work. The charcoal definitely took up some the alks, always an issue with AC cleaning, but the results, so worth it.

I normally do IPA-rex of fumarates, if you catch it at the right time, you can crash out a yellow fraction (still mostly DMT fumrate), and then crystallize the pure white/colourless fraction. But in other cases i've had trouble making this separation. But if it works you don't lose any material. you just get two different grades.

What you have shown here is that AC is a 'quick and dirty' method to obtain colourless crystals, despite some losses. I love it.

And you are right, water is undervalued in the standard methods. And its green chemistry too, that is ideal.

Although, AC might work better in the non polar phase too, you might lose less yield too. What solvent did you salt the fumarates from?

Water, I think, if I understand the question. I freeze precipitated from naptha, put aside a gram of FB for changa and put the rest in warm water and kept adding fumaric acid until everything was dissolved. And then cleaned up excess fumaric acid like this.

Hm when you say AC might not absorb as much alkaloids in the non-polar phase do you mean in NP solvent, or just when the alkaloids are freebased? My simplistic understanding of how AC works is that it is porous and stuff gets caught in the pores, so since FB is a smaller molecule than fumarate, less of it would get caught? It might be interesting to try this with the NP solventless methods discussed in Endlessness's ethanol/sodium carb thread, and see how well it would clean up the product.

Yes, I mean in the NP solvent.

Thats right, larger molecules will stick preferentially to the activated carbon, but sometimes ions will stick more to the activated carbon than if uncharged. Particularly organic anions are known to do this, like fumarate.
However, it may make no difference at all, just a thought. But it might be worth a try to do the AC step before you freeze precipitate, and then convert to fumarates and compare the two, it might save time and yield.

Also, to prevent losses you can use less activated carbon, you don't need much, maybe 10% the weight. I just add it bit by bit until I see the colour mostly gone.

Thanks Mindlusion. One more question - do you have any tips for dislodging this stuff from the evaporation dish without bits of it flying all over the place?

ah yeah, when crystallized out of water the stuff is hard as rock. Sometimes you can get away with just holding a sheet of aluminum foil or something over the pan when you scrape it, otherwise you could try to redissolve it in another solvent and evap or recrystallize, but that's probably not necessary and kind of defeats the purpose of using water in the first place hehe.

Did you vape any of the crystyls you produced?

What diference did you notice compaired to freebase ARB form??

Sometimes rmoving too much.. lowers the quality of the trip experiance...