Potassium Hydroxide - Diaphragm Electrolysis ep3 

I found a site that speaks about magnetite electrodes for electrolisys:www.chlorates.exrockets.com/magnetite/magnetite.html

Thanks for the tip! I always saw that product in stores and noted that it contains some calcium nitrate, but I never realised the nitrate was in its own separate bag. That's really useful! I'll have to get some next time I'm at Bunnings.

Making HCl from the H2 and Cl2 output is a plan for the (likely very distant) future! Just need to find the time, and convince myself that I can do it safely.

making a HCl burner is like making a oxyhydrogen torch: one misshap and sonething may explode

You're 100% correct on the fact that it would minimise the OH- transfer, and it would definitely work to increase the efficiency of the process. However, like many things, this is a trade off: As you've mentioned, the conductivity would be (on average) decreased, slowing down the production rate. Additionally, the solution you generate would not be as concentrated, which is usually less desirable. In this case, you'd really just have to weigh up the factors of efficiency, speed, and concentration to see whether or not it's worth it.

It's unlikely. In most cases, porcelaine is glazed, preventing water absorption. In the cases where it is unglazed, it will also need to be porous enough to allow water to slowly pass through. There aren't many types of porcelaine that will work for this I'm afraid.

mixing H2 and Cl2 in the same place and lighting it up inst a good idea Have you ever seen a oxyhydrogen explosiin? yeah about that. in an amateur setting it would be hard to make a HCl burner :/

I’d probably avoid it if possible. It will work but you’ll be setting yourself up for lead contamination during operation, and even more contamination when the anode eventually fails (especially if the electrode is homemade). Graphite is also a valid option if you want something cheap and don’t mind carbon particles in your anode solution. That being said, if you have the setup to deal with moderate amounts of lead waste, you should be fine to use PbO2, it’ll make an effective anode.

I'm sorry to hear that, haha. Either way, I'm glad to hear that you've given this a try, and I'm thrilled you enjoy the videos! As for your prediction of what happened, I'd agree with everything you've said. By reversing the polarity, you're now pulling the chloride ions through the diaphragm instead, giving you copper chloride in the anode compartment, and a mixture of potassium chloride and potassium hydroxide in the cathode chamber.

Allow both flows of gases to come togheter in a spark gap behind a fine mesh network (to avoid flashback), alternatively in place of the spark gap you could just allow a catalyst gauze (Platinium)... or a flame... and it should burn to water... Voilà you reinvented the oxhydric blow torch or an HHO generator/burner...HHO fuel cell... The simple compression of H2 and O2 against a glass surface may be enough to induce ignition if the amount of initiation of free radicals is sufficient to sustain and accelerate the free radicals formation, propagation chain and recombination/ termination into H2O and heat/energy. As a side note combustion is a radicalar process... Alternatively you may drop water onto a very hot surface above 2000°C... 3000°C would be better...because water vapourization and decomposition are highly endothermic processes with relatively high activation energy... The water will first vapourize then atomise/plasmatise into H2 and O2 or eventually H° and °O° then recombine into H2O and heat... practically one observes two explosions (an endothermic one first and then an exothermic one)... the overall reaction is endothermic despite the recovery of some energy by recombination... This means the dissociation energy is higher than the recombination... but theorically if the system is very hot (infinite energy) this energy difference becomes negligible and the equilibrium tends towards a fifthy fifthy dissociation and recombination... such a place could be the sun except it has too much hydrogen vs oxygen what would displace the equilibrium.

I have a video showing how to convert a PC power supply into a usable desktop supply here - ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ygvbdwl-0bM.html (note that this video is a pretty old one, so excuse the poor quality and the fact that it's pretty boring). After that, you can get a simple $15 current controlled buck converter on ebay, which you can hook up to the 12 V line. Once you've done that, you'll have a fully current/voltage controlled electrolysis power supply.

@@ScrapScience I found what is called a "breakout board" on line, I think it came from an outfit called Garden Electronics. You merely plug in an ATX power supply and feed the buck converter off the appropriate terminals. I can run multiple buck converters off one supply and still have my supply intact should I need to stick it back in a computer. BTW, love your work, it opened up a whole new world of amateur chemistry for me and put more reactants at my fingertips. Even sodium hydroxide is getting to be "behind the counter" here in the states because the bathtub meth labs use it in making their poison, plus I my own make "bleach" for 1/3 the cost of buying it at the store (I use distilled water, the biggest expense) that's not full of contaminants like OTC bleach

As Alexandre has stated, dissolving lithium metal (which is pretty easily available from batteries) in water is a very effective way of making lithium hydroxide. But yes, I'll definitely eventually be testing the efficiency of lithium in the chloralkali process. In fact, by the same reasoning that makes the potassium process more efficient, the lithium process should actually be even less efficient than the sodium counterpart, but we'll be checking that. I don't have any lithium salts at the moment though, so it'll be a while before we'll get there.

Lithium is a little weirder like most first member of an elemental column (not counting H and He)... those first members usually display properties of their family members (here alcalies column I)... but also they share properties with the members of the next column onto the right into the periodic table... here alcaline earth metals (column II) For example LiCl is mildly acidic and hydrolytically unstable... it forms a little LiOH and HCl in warm water. Li2CO3 is almost unsoluble... Its chemistry is not as straightforward as Na-K compounds. LiOH ressemble to Ca(OH)2. So definitely to be studied... I wonder what happens when trying electrochemical LiClO3 and LiClO4 from LiCl...

Probably not at this stage, but if I ever need pure potassium hypochlorite, that'll be the plan.

@@ScrapScience I had KClO3 in mind from Cl2 and KOH.

I'm currently working towards a future video which goes over the production of potassium chlorate, in which everything will be explained properly. But basically, while you can generate potassium hypochlorite by the reaction of KOH and Cl2, and then boil the solution to generate potassium chlorate, the chlorate is much more efficiently made by direct (non-separated) electrolysis of a potassium chloride solution. I'll probably stick with that rather than going to the extra effort of a full chloralkali cell if I need chlorates.

@@ScrapScience I've been using a KCl solution to make KCl3, it's not bad, but I definitely need to up the size if I want to make anything useful. I have been thinking about making HNO3 to be able to make a few other... reactive substances, however, I don't have a way to distill it and I don't quite want to go down the electrolysis route for that. That being said, I do have ample amounts of KNO3 that doesn't have too much of a use.

Oh yeah, the table is definitely a bit weird. It was just the best result from a quick google search that had reasonable values for OH-, H+, Na+, and K+. I would definitely not trust the actual values themselves, but I just needed a simple table that could show the relative values of the ions to get my point across. And those units are definitely weird, I didn't even notice that. I think I'll definitely be finding a better source of values for future videos that involve the same principle.