A low-medium frequency buzzing noise, coming from an air compressor, originally a medical implement of some sort, came from a hospital and found its way to Lestat by way of its being first traded in for store credit by somebody at a pet store, and the pet shop owner finding it gave off too much vibration to be suitable for aquaculture, so it was sold by the pet store owner to me, as he knew I'm a chemist, since I come in there for supplies, and he's seen me for example, take in condensers and pumps so I can match the right size tubing for them, and completely clean him out of things like sulfur and formaldehyde
And since I have no interest in keeping pet tropical fish whatsoever, he realized I was most probably the one and only customer he could ever get rid of that pump to, and sold it me at just the price he gave whoever it was that sold it him for store credit, so I got it for just £5, a bargain, considering its quite powerful, and being hospital equipment and thus medical grade it HAS to be reliable, so it is doubtless something that would be pretty expensive if bought new from the same source as the hospital got it from.
Got that turned on atm, and its buzzing and humming, I've got it connected up to a flask, that atm contains a small quantity of concentrated sulfuric acid, last used as a gas generator, in a 2-neck round bottom flask, so I could connect a pressure-equalized addition funnel containing concentrated hydrochloric acid, stoppered at the top to prevent the HCl gas from simply backing up the pressure-equalization side-arm and going up and out of the top, and thus making it go out of the other end, equipped with a bit of a custom improvized piece of glassware of my own, after a separatory funne broke, just at the half-way point of the tap, leaving essentially a stopper with a hollow bore through the entire length, that can be fitted with a piece of plastic tubing and that used to direct gases generated in the flasks. In the case of this kind of hydrogen chloride generator, the powerful dessicant effect of concentrated sulfuric acid, when the conc. HCl is added slowly, either dropwise, or a little splash at a time, the conc. (98-99%) H2SO4, acting as a dessicant, absorbs the water in the aqueous hydrochloric acid and the hydrogen chloride passes through the H2SO4 and is dehydrated in the process, passing out through my little recycled, modified gas outlet-stopper that I hacked and reincarnated the busted sep funnel to make. The air compressor is purging the H2SO4 so it can at least be used for other things, or the water boiled off to re-concentrate the sulfuric acid. Mostly done now I think, at least the flask is no longer belching clouds of hydrogen chloride fumes when compressed air is blown over the surface. Time to exchange the surface flow for a fine-bored glass pipette attached to the plastic tubing currently there, so it can be placed under the surface of the still very strong sulfuric acid without coming to harm (the plastic tube would simply be disintegrated by the acid, I only needed a small amount of HCl gas to prepare a solution of anhydrous hydrogen chloride in anhydrous isopropanol (for adding to nonpolar solvent solutions of amine freebases and forming salts that can easily be separated either by flooding with a larger volume of a polar sovent in which the formed amine salt is insoluble, or distilling off the solvents, it works much better IMO, or at least is far more convenient than using acidified water, since doing it with anhydrous alcoholic solutions of anhydrous HCl allows much better, cleaner crystallization, and additionally, the boiling point of the alcohols is less than H2O, so its easier to distill off, and allows the solvents to be distilled at lower temperatures, avoiding excessive heating of the amines, which is especially convenient should the hydrochloride salts be volatile with heat.
