Comments, 4-FA solubility, possible cleaning method
Today one my friend received a batch of brown/"salmon" coloured 4-FA...! Never heard of it anywhere so obviously I ask, is it even 4-FA? Maybe cut with something, but it is consistenly slightly brown and also seems more crystalic, my own batches were a bit more like dust..
I'm not sure there is published data on 4-FA's true color when highly pure. Not all chemicals are pristine white in their most purified forms (for instance JWH-018 is a clumpy-ish yellow when pure according to the creator Mr. Huffman. It is fairly common practice for labs to cut or otherwise bleach the color out of these chemicals before selling them due to the common customer thinking whiter means purer). It is also interesting or at the very least relevant to note that even a disgusting looking powder can easily be 96+% pure. One example that comes to mind is some JWH-018 that was a deep brown sticky goo/oil was tested and still exceeded 96% purity. So an ugly chemical does not mean highly impure. Since the total dose of 4-FA in a night can exceed a gram in some individuals it is worthwhile to note the impurities can become dangerous in these amounts. 4% impurity in a 1000 mg sample is 40 mg. 40 mg of certain chemicals can be quite damaging (I don't know which precursors are likely to be in a contaminated sample of 4-FA so I can't guess how risky this is).
You might want to try cleaning it before tossing (or consuming) it. I did some solubility tests on my 4-FA. I didn't evaporate any of the solvent so I don't have exact numbers of solubility. As expected 4-FA is highly soluble in water (30 mg into a couple mL no problem. Quick with little agitation). Somewhat unexpectedly (for someone who knows nothing of other amphetamine solubility) undried acetone (so prolly 95-96% acetone and 4-5% water) was a poor solvent. It broke up the chunks / clumps into a fine powder that is easily stuck in suspension, but when left to rest settles out. No perceptible amount has dissolved into 7.5 mL of acetone. Again, though, I did not evaporate the acetone to see how much did dissolve. It did not seem like much, though (agitated ~20 minutes, room temp acetone). And I also did an undried heptane (should be roughly equivalent to naphtha) test. The heptane didn't seem to affect the 4-FA much at all. No powder appeared to go into solution. In addition the chunks and clumps didn't even break up at all unlike in the undried acetone test. The chunks stayed firmly grouped and settled immediately after ending the stirring. Heptane was cooler than room temp (prolly as low as 50-60 degrees F) and it was agitated for at least 20 minutes with no apparent change.
So. My recommendations considering the above. Try a naphtha (preferably dried, but mine wasn't) wash first. If that doesn't leave you with a white powder try an acetone wash (preferably dried) second. If that doesn't leave you with a white powder you might want to try to dissolve your impure powder into a few mL of water. Hopefully the impurities won't be water soluble and you can decant / filter them out and evaporate the water to get back the 4-FA.
Do a test wash before throwing your whole supply in. It is best for the solvents to be dried first (look up a tek with epsom salts for the simplest method). Just take a small amount (25-30mg) and do a naphtha (or heptane if you have it, but it's more expensive) wash. Just take a small thin jar, add the 4-FA, then add a few mL of naphtha/heptane. Stir / agitate for 10-15 minutes or so. Decant or filter out the crystals at the bottom and dispose of the naphtha. The same procedure would be used for the acetone (but you might want to use a smaller amount of solvent and even have it refrigerated to reduce the 4-FA solubility as much as possible) but it will take much longer to settle and be easy to disturb when decanting. You may or may not want to test how much acetone it takes to fully dissolve 25mg of your material. This will let you know how much 4-FA you will lose for each mL of acetone you use in the wash (it should be a very small percentage, but not as small as naphtha). The 4-FA should be left on the bottom of the container (NOT IN SOLUTION) just like the naphtha/heptane wash.
A last resort is the water dissolve. It is more time consuming and probably won't help, but it may just work. Dissolve your powder in as little water as possible. Just add it drop by drop and stir until the vast majority is dissolved (hopefully leaving behind a bit of yellow / brown gunk or goo. If this works it is because the impurity was less water soluble than the 4-FA. Using as little water as possible will give you the highest chance of a pure end product. Decant or filter off the water and evaporate it (this time the 4-fa should be IN SOLUTION) to recover your 4-FA.
I hope this helps someone at some point. Solubility data at least will be helpful to some googlers eventually.
D) and I noticed the headaches the day after. It happens to me if I use 4fa 2/3 times in a week, or even just one, so I think I'll switch to something else for my study sessions.