PrimoP, whenever I put 30% (battery) sulfuric acid into say 3 volumes antifreeze and then boiled, I've so far got wet dioxane condensed. Haven't found a way to screw it up yet. Never calculated yields, because I never tried to boil it down past ~3/4 of the solution; after cooling I tossed it. We don't have to bee tight-assed about technique for something like this, do we? I was using this crude wet dioxane with (muriatic) HCl, to oxidize lignin to Hibbert ketones Post 214730 (https://www.thevespiary.org/talk/index.php?topic=11470.msg21473000#msg21473000)
(halfapint: "The Hibbert Ketones of Lignin", Novel Discourse), a reaction in which the amount of water wasn't critical. Never dried, so never measured its concentration; I'm so ashamed. :-[ I'll bee better after this, promise!
turning science fact into <<science fiction>>