Back in the day I would only ever use limonene to extract.

Only issue was, unlike xylene, salting the limonene pulls would take forever. With trial and error I found out how to get the most beautiful sparkly citrate xtals; problem was I'd only ever have a successful salting if I placed the salting vessel in a hot water bath at 70 C for 45 minutes periodically shaking it vigorously. So if I extract one pull three times this amounts to over 2 hours of baby sitting a hot water bath and vigorous shaking every 15 min.

has no one else found it much harder to salt limonene than other petroleum solvents?

Limonene is much more laborious to salt. I use sulfuric acid to salt and simply shifting the ph takes a HUGE amount of shaking. Xylene is very quick and the alkaloids really don’t like sitting in that layer.. Limonene is not as straightforward and the salts will linger in the solvent, moreover the freebase will be much slower to covert in limonene. The ph can drop low after acid addition and then take a lot of vigorous shaking and stirring to raise it back up to basic. Xylene on the other hand can remain basic for most of the salting stage untill all the freebase is used up and the ph drops rapidly.

The lack of efficiency with Limonene however, is worth the trade off IMO.

Perhaps there is an acid that is more effective?

I heard you can't use HCL because it will denature the limonene into limonene oxide or something. Sulfuric is ok and doesn't create this problem? The weaker the acid the more difficult the pull maybe? Is there any acid in between sulfuric and hydrochloric that may pull faster? Is there a way to abet the process? Is acetone miscible in limonene? Maybe doping the water with acetone or another chemical that is immiscible in one or the other may improve the speed?

The time and effort is my drawback to limonene; which makes gassing xylene sound nice.

Does salting spice from limonene have the same time investment drawback?

Limonene is simply more reactive and tiny amounts of oxidation or hydration impurities make it very sticky. Direct HCl gassing of limonene is out of the question for sure. Sulfuric above a certain strength would also cause inconvenient reaction byproducts.

Xylene doesn't smell that bad (and is even named after wood, so it must be fine )

I prefer Limonene because of the smell, but yeah there are trade offs. To add to what DWZ said, I tested Limonene with 10% ammonia as a base and saw a discoloration reaction.

I never played around with citric acid but I never ran into any issues with FASI salting, imo the best way to crystalize both mesc as well as dmt fumarate.. Easy, effective, and beautiful.

With hcl salting of mesc it was a bit more tricky, finding the right pH.. too little and the salting solution came out basic and with small yield, and too much and the mesc came out black, lol.

^ What is the FASI method?

Is this an acronym for a specific acid or a technique? Is it related to salting limonene? Did you use limonene with this method?

For some reason the only acronym I can think of is Fumarate Assisted Solvent Impregantion...which I am sure is definitely not a thing.

So what does it stand for? Is fumaric acid involved? Hmmm, Fumaric Acid Salting?

I found citric to be very reliable for getting good xtals with limonene; it was just the time investment that was the down side.

Also; I had some older limonene that turned a orange color all on its own; I suppose it oxidized or something. It produced terrible emulsions of a sickly green color upon salting. I guess fresh limonene is imperative. It doesn't seem to store well for long with a significant atmosphere. Storing it under a nitrogen atmosphere is probably the best way to preserve it. Altogether more complicated that a more stable solvent.

I think there is a solvent synthesized from renewable chemicals called Sabinene; that does not have the stability issues of limonene or the noxious smell of other aromatic petro based ones. I think it is difficult to procure though. Never used it.

Might it be so that there could be a limonene soluble antioxidant that could protect limonene from oxidation or hydration reactions? Maybe something limonene can be "doped" with in a small proportion that will improve salting efficiency or protect it from oxidation/ hydration?

FASI details: https://wiki.dmt-nexus.me/The_FASIPA_Method

It works for mescaline in Limonene too like endlessness said. I used it, and it worked well several times, but a couple times it made super small x-tals that I could not catch in a coffee filter. Some kind of user error on my part, but I could not figure out how to consistently get the easier to handle mescaline fumarates even when going slow.

Now I just titrate Limonene with sulfuric water. Yes, it takes some shaking, but it's not a big deal for me. I just think of it as an arm workout day 😅. I also love how it xtalizes when concentrated and mixed with acetone 😍, those xtals are always needle like and super easy to catch.

To each their own. At some point it comes down to personal preferences (do you prefer not filtering, avoiding smells, not shaking, etc).

I think I can guess why Limonene/FASI sometimes gave me an unworkable powder that would go through the coffee filter. I was not controlling the pull time or temperature. If pulls are too aggressive (warm limonene from the summer heat and pulls too long) more plant matter will move to the limonene and crystals could be smaller. Controlling that part of the extraction (temp/time) will likely make crystals more reliable.

Currently, I much prefer doing 60s chilled ethyl acetate pulls and simply salting directly with a dollop of citric acid granules which reliability produce long mescaline citrate needles very easily. Ethyl acetate is half the price as limonene for me and there is no need to manage a FASI solution or deal with sulfuric titration, reduction, and a dual solvent xtalization.