For price sake and availability, I could do with producing my own acetic anhydride. Most likely the easiest way to do this is to acetylate glacial acetic acid (which I have plenty of), mainly want it for producing other anhydrides, but the easiest, practical way to do it seems o be using ketene. Now, I can build a ketene lamp alright, but the problem is, ketene, CH2=C=O is REALLY fucking nasty ass shit. So it will have to be remotely operated, and EVERYTHING discharged through scrubbers and any exhaust gases burnt, because its about ten times the toxicity of KCN (potassium cyanide). Not as bad as say, phosgene, but close enough to stare up phosgene's arse crack. *shudders*
This is something that will need every precaution, and only to be operated at night, when there are no possible bystanders, since one breath is enough to do for you. I'm not trusting my gas mask to that. No way. But when ketene is passed into glacial acetic acid (GAA is just extremely concentrated, waterless acetic acid) it forms the anhydride. Probably some of the nastiest shit I'll ever have handled. bar maybe some of the mercury salts, hydrogen sulfide and iodine monochloride, although excepting H2S none of those has anything near that kind of lethality. Going to build a self-contained, fully remote operated reactor for this, to house the ketene lamp itself. Easy to make the stuff, dangerous to handle, the core of it is basically a reflux still that boils and vaporises acetone, the vapors rising up a condenser and going past a heated resistance wire coil of platinum wire or nichrome (got the latter), the acetone rises up past the coil, some ketene is formed, then the rest passes back down in a cycle, the ketene gas is tapped off, impurities are removed in a second column, condensed in a flask, and then the ketene gas is passed out, pushed by a stream of inert gas into a container of GAA, which over time, as enough ketene is slowly produced, forms acetic anhydride. I'd rather not buy AA, since heroin makers use it to acetylate morphine. Not me personally, since there are better things I could do with morphine if I chose to do so. I'll just build the thing tonight, probably not test it, since I only have a very little bit of acetone left atm, and that has been especially treated, and the bottle is kept sealed to keep the drying agent drying only acetone and nothing else, for when I need it anhydrous.
Might wait until more gets here, or somewhere in between. Because I'm tired, cranky and need sleep.