Crack cocaine
Mac n cheese
Weed science. Not complicated at all, but there’s so much bro science out there…
Liquid gas column extraction of organic compounds? I’m told that’s something you should definitely do outside!
Alcohol isn’t that great as an organic solvent. Are you using the air fryer to evaporate? That must be a fair fire risk!
Butane on the other hand is a good organic solvent and will evaporate at room temperature (just don’t evaporate it in a room or near any heat source).
For me it has been etching circuit boards and specifically making my own liquid tinning solution at one point. I mostly do hydrochloric acid/hydrogen peroxide on larger stuff and ferric chloride on smaller prototypes.