Hydrogen Gas Generator FAQ 1.0by Drone #342
I dedicate this post to ret. Gen Barry McCaffrey, whithout who's leadership, our victory in this war may have never been imaginable in this lifetime. Thank God for unqualified, ineffectual reactionary morons.
Today, I want to talk to you, the workin' class grunts in the War, about what I call "God's gas": elemental hydrogen. I'm sure all of you can think of at least a few different uses for it at home: reduction of nitrostyrenes or nitrovinyl indoles to phenethylamines and tryptamiens (respectively), reductive aminations on a massive scale, recuction of hydroxyl groups, or perhaps a miniature historical recreation of the Hindenburg tragendy. All of these are fine and dandy, provided that if you decide to use this information for any of the aforementioned hobbies, you do it in full accordance with the law; always ask yourself: "what would Nancy Reagan think if she knew I was doing this?" Remember: laws regarding health and safety, drugs, and national security were made for a reason; they are not yours to question. Don't break the law.
Now we got that disclaimer out of the way, let's talk about hydrogen, and how to make it drone-style. How do I make it? Simple. I react metallic magnesium with sulfuric acid, resulting in epsom salts and hydrogen gas in the following formula:
The reaction happens fast and hot, and its lots of fun to watch. This is really a nice way to generate your own low-pressure source of a very expensive, difficut to get gas. The key here is in the apparatus set-up. But let's start from the beginning anyways.
Magnesium is used in the housing of many different pieces of electrical hardware -- the chassis for hard drives, the housing for motors, etc. Its an extremely light metal (d=1.738 g/ml), and has a unique look to it that is relatively easy to discern from aluminum. I get mine from a scrap yard. After purchasing a piece-o-shit Soviet-esque motor, I delicately (snicker, snicker) dismantle the thing with a pair of heavy-duty vice grips, a sledge hammer, and a pair of pliers. After stripping all the good metal out of it, I rinse them with a little acetone to get the grease and crap off of it (not that it matters, but I'm anal that way.) From there, I continue to "get medieval on its ass" with the aforementioned tools until the pieces of magnesium are small enough to fit into the mouth of a 250 mL side-arm flask. I weigh out about 24-25 g of the metal (1 mole), toss it into the 250 mL side-arm flask, toss in a magnetic stir bar, and add about 50 mL of H2O. This is nestled in an ice bath upon a magnetic stirer. Attached to the top opening of the side arm flask is a 150 mL pressure-equalized addition funnel, filled with 110 g (approx. 1.1 mole) of chilled, concentrated H2SO4. The side arm itself is then connected to a rubber hose, which is then connected to a glass tube stuck through a rubber stopper in yet another side-arm flask (100 mL) filled with a small aliquot of 50% KOH. The end of this glass tube protrudes into the KOH solution by just a centimeter or so. This second reactor vessel is nestled in ice as well, and it acts as a scrubber -- eliminating any unwanted H2SO4 fumes from being added to your final product. The side arm of the second side-arm flask is then connected to a second rubber tube, and this is attached to the actual final reactor vessel -- yet another side-arm flask.
In the third and final side-arm flask, the rubber tube from the second flask is attached to its side arm. On the mouth opening of the third flask, a ballon is attached; this will help in storage of unreacted H2 gas, as well as help prevent unexpected jumps in pressure.
The contents of the third reactor vessel are added (whatever you are trying to allow to react hydrogen with), all the joints are wired tightly shut, though the balloon is left off for the first minute or so, and we're ready to rock-n-roll. The mag-stirer is turned on, and the H2SO4 is dripped in. In a matter of moments, fizzing is observed on the surface of the magnesium, and away we go! Hydrogen gas is generated, and for the first minute, its allowed to flush through the system -- pushing all the useless air out of the vessel. The ballon is securely attached, and slowly it begins to inflate.
This reactor will producce 1 mole of hydrogen gas; obviously your needs for this beloved gas will vary, and conveniently this apparatus is easily scaled up or down accordingly. Iron or almunim will work for this reaction as a substitute for magnesium, but I prefer to use magnesium since the sulfate is so innocuous, dissolves so nicely, and generally is easy to deal with. Also, due to its low atomic weight, there is less waste to deal with too. Other mineral acids will work, though the problem with HCl is the massive quantity of HCl fumes that will need attending. Nitric acid won't react well with aluminum.