Build an Alkaline Water Electrolyser to Produce H2 | High Output

[@charleshughbryan5603]

Great video ! The DYI science guy on u- Tube used a similar cell with microfiber for separation. He disassembled it to repair leaks and check for formation of hexavalent chromium. He contained the leaks from the cell by playing it into a plastic tub. He had a dissecant dryer and refrigerator compressor to pump from a beach ball into an LPG container. Very inexpensive and amusing too. I'm building a similar system and running it on my solar/ wind power generator. Keep your videos coming and thanks for sharing. Charlie

[@jimbaybee]

Thank you for this video, Dominic. I'm trying to design a prototype now and your video has given me some ideas but I might need a sort of step-by-step guide.

[@seamusconlon955]

Very well explained Dominic.

[@dominicogallachoir4554]

Thanks Seamus!

[@Guoenyi]

Beautiful. The fizz is just beautiful. I will make a cell similar to this.

[@dominicogallachoir4554]

Good luck and please let us know how it goes 😁. I'm planning to make a "version 2" myself as well

[@Guoenyi]

@@dominicogallachoir4554 Hey good luck on that! I know gold is expensive but it seemed to be a good electrode surface. I published a paper of my work done with pure water and gold plated electrodes in a miniature electrolyser cell (I did not bother with gas separation for that was not the purpose). The results are consistent with your prediction. Low voltage can result in more efficient reaction albeit at a very low rate. See it via this link doi.org/10.1098/rspa.2017.0371 If you are not a subscriber of the journal you can request a free copy by emailing me. Just a warning, it is a lot of theory from the simple experiment.

[@dominicogallachoir4554]

@Guoenyi, thanks for sharing your article! It seems to be open access, or at least I had no trouble accessing it. While I did struggle with a lot of the theory, one thing I definitely understood was that you've shared the original data freely on the internet, which I think is a super cool thing to do. Hahaha I'm definitely not going to take credit for predicting electrolysis below 1.23 Volts. Highly-efficient for me would be more like

[@Guoenyi]

@@dominicogallachoir4554 Not a user of linkedin. I am on researchgate though but I can't seem to find you there. I will consider joining linkedin after taking a look at it. Not familiar with that platform. No more gold. The paper was a proof of concept for under 1.23V water electrolysis supported by quantum tunneling theory. The experiment deliberately picked impractical setup e.g. ultrapure water, gold electrode to demonstrate the physical nature of water electrolysis. My current work is on practical electrolyser operating under 1.23V. This is done for for higher efficiency reason (less waste heat). Also gold will not be used as it is a precious metal. I might try starting with nickle plates to get a prototype working first just like yours. Then the idea is to modify the electrode surface with porous carbon for larger effective area. The higher area should make up for the loss of reaction rate from running a low voltage (when we compare a porous surface to a flat surface of the same geometrical area).

[@dominicogallachoir4554]

@@Guoenyi I've been thinking about your paper and trying to make more sense of it. So, as far as I know, most electrolysis cells produce waste heat in proportion to the "overvoltage". In other words, waste heat is proportional to the actual voltage minus 1.23 V. At 1.23 V there is no waste heat. Now I'm wondering, below 1.23 V, if the temperature of the electrolysis cell actually drops. In other words, the reaction consumes heat energy... I suppose it could be called endothermic. Is this correct? Is some of the ambient heat energy converted into chemical energy in the form of hydrogen gas?

[@sunlaser6587]

Nice! I made almost the same prototype some years ago. I used epdm rubber aswell, but i noticed that after a month or two it was mandadtory to retighten the screws, cs the stack was loose, and significant leakage of the electrolyte happended. To counter that i moved on to use pp plastic for the spacers. Also i increased the electrolyte concentration to 30% to increase efficiancy, and hydrogen production (more amperes can be put in the cell with same voltage). I had about 6 electrolosys cells in series with a total voltage of 11-14V at 5-40 amperes. At 40 amps it produced about a 1lpm of hydrogen and 0.5l oxygen respectably. Though i am curious on which membrane material you used, and why you chose to do 2 membranes per cell instead of 1. Did that improve the hydrogen and oxygen purity? Well done, keep it up^^

[@dominicogallachoir4554]

Very interesting! Disappointing that EPDM breaks down over time but good to know there's a better solution. Yes, I originally used only one membrane per cell but the gases were not fully separated (formed an explosive mixture) so I added a second one.

[@dominicogallachoir4554]

Do you have any advice regarding membrane materials? Especially with 30% electrolyte concentration; that's pretty strong. KOH or NaOH?

[@sunlaser6587]

@@dominicogallachoir4554 Now i noticed that many plastics broke down because of the caustic properties. But bastically only plastics that have a carboxyl group in the main chain where broken down, because it undergoes a saponificationreaction. an exaple that doesnt work is for instance PET. Plastics which do work are pp, ptfe, and some others i forgot. PP is the best plastic, because of it's fantastic mecanical properties (stiffness) chemical and thermic resistance, and a good oxidation resistance. My electrolyser reached temperatures of 60°C on optimal performance. and that heat is rly not good when u have 2 iron pressureplates that force the stack together with 5 tons of pressure. A plastic with low melting point and not high stiffness would begin to deform easely. Regarding to Koh or Naoh, i tested if there is a difference in efficiancy, and i couldnt notice a difference. but my testingequipment was rly limited, and also my time. So take that with a grain of salt. But if u use koh, then the flame looks nicer in my opinion, because it doesnt look that contaminated. But i used only naoh, because was easier to get in larger quantities for cheap, and it is a good indicator, if your final gas is pure or not. I tried many filtering systems, but none where able to get out all of the atomised electrolyte particles. It's rly time to make a next prototype and fix that problem with good filters. xD that would about be my 20th prototype regarding an alkaline electrolosys cell, though i do admit that the first ones where not working, and only a proof of concept...lmao Hope this may help u a bit

[@sunlaser6587]

@@dominicogallachoir4554 The membrane also consisted out of pp. And it was ridiciously cheap^^. Took me a while to find out: garden fleece (the thin stuff) has a rly small pore size, meaning good seperation, though still has enough electrical conductivity, and it is made from pp plastic, meaning it's perfectly suited for this application.

[@dominicogallachoir4554]

@@sunlaser6587 That's extremely helpful. Thank you so much for your input. I was about to ask how you managed to achieve a seal when the gaskets are made from rigid PP - I guess that's what the 5 tonnes of pressure were for. That's an interesting observation about the carboxyl group and it makes a lot of sense - NaOH reacts with carboxylic acids/esters to form soap as you said. However, that makes me wonder why the problem with EPDM rubber? Perhaps it's just an exception. Or maybe NaOH breaks open the C-S (vulcanisation) bonds as well It sounds like you're a long way ahead of me in terms of developing this technology! I'd be super excited to read more if you've published any of your results.

[@superchillmusic8453]

Can I have the Parts List? And Cad Models? Would be awesome! Thanks

[@dominicogallachoir4554]

CAD models (FreeCAD format): energyd.ie/cad-files-for-diy-water-electrolyser/ I don't have the parts list unfortunately

[@superchillmusic8453]

@@dominicogallachoir4554 Thank You!

[@androidmustafa]

Hey Dominic one question.. What was your hydrogen production rate at 40 amps? Assuming you improved your cell also what would be your theoretical production rate for the given surface area of your cell? Appreciate your video and effort. Keep it up💯

[@jimviau327]

Great build. I'd like to make one . Can you explain how you built the membrane? What's it made of ? Thanks.

[@dominicogallachoir4554]

I cut the membranes from polyester. I would recommend using a high-quality fabric scissors to cut them and a template to mark them out

[@dominicogallachoir4554]

Good luck with the build. Please let us know how you get on and make sure to read the other comments here as people have shared a lot of great info

[@jimviau327]

Dominic Ó Gallachóir thanks for the quick response. When you say polyester do you mean polyester fabrics like found in clothing?

[@dominicogallachoir4554]

@@jimviau327 Yes polyester from old clothing. It performed okay in my experience although I'm pretty sure it will dissolve if you make the electrolyte really strong. I'm also not sure about long-term performance. If I were making another cell I would probably look for polypropylene fabric as it's highly chemical resistant.

[@nikoskaravitakis9437]

super impressive. Ill make one of my own since i have time in quarrantine. What cloth are you using in the gas divider as membrane?

[@dominicogallachoir4554]

Thanks :) If I remember correctly, the gas divider membranes are polyester (recycled from an old sports top). Choosing a material for the membrane is tricky. I know mine held up fine but then again it wasn't in use that long. I've also heard that polyester will dissolve if you use KOH rather than NaOH. Nylon is well worth considering too. A trick I used to make it easier to cut out the membranes was to spray them with starch and iron them before cutting. This made them stiff like card rather than floppy like cloth. I also made a few mistakes that you might learn from. My plumbing holes were not really far enough apart - it was very tricky to screw all the connections into place. Also, I should have included a drain tap/valve which would have made it much easier to empty the NaOH solution out once I'd finished. I would also say that my cooling system didn't seem super effective. Finally, give some thought to getting a good electrical connection from your power source to the first electrode. I used a stainless steel screw (poor electrical conductor) and that whole area got pretty hot. Very best of luck with your project :) I would be fantastic to see a video at the end, too! BTW I still have the CAD files and can send them to you if that would be any help to you.

[@nikoskaravitakis9437]

@@dominicogallachoir4554 the designs would help a lot even though Ill make it a bit different. Ill use many contact points on the ss electrodes to help the current pass better. Also thicker electrodes would help with conductivity even though they would be more expensive. I can send you my email so we can talk if you want.

[@nikoskaravitakis9437]

@@dominicogallachoir4554 ill make a video if sucessfull. Also surface area per volume of H2 must be calculated. I plan to make 6lpm H2 per minute on a multiplate design

[@dominicogallachoir4554]

Sure, send your email and we can discuss further

[@nikoskaravitakis9437]

@@dominicogallachoir4554 let me know when you get it. Thanks

[@santoshmane3383]

What kind of membrain (materiel) do you use for separate Hydrogen ?

[@CatboyChemicalSociety]

he uses polyester membranes as a porous barrier. crosslinked PVA works too for higher quality membranes with ion exchange.

[@mukundanm2666]

Whats the output flowrate of hydrogen Gas on this build in Lpm? could you share me the entire design of every components that you have used in this video? Thanks!

[@aleksandarpetrovic6613]

I didn't see membranes 🤔

[@hansscholte5472]

Hi Dominic, very good video! I like it, thank you. In order to increase: it’s very attempting to increase current, but it only creates heat. Keep the current low and simply double your cell (or triple etc it) to increase the output. Check out Robert Murray-Smith on YT; he has been testing with graphic foil instead of ss with good results. Another option is not using DC, but pulsed DC, that jumps up volume. I don’t know the effect on corrosion. Good luck with your projects!

[@dominicogallachoir4554]

Graphite may be worth experimenting with, but long-term durability is questionable because graphite can react at the anode and dissolve into carbonates (see doi-org.ucd.idm.oclc.org/10.1016/j.electacta.2010.11.071). Cell size is a balancing act: Bigger is more efficient, but also more expensive.

[@jitalsc]

VEJA O NOSSO VIDEO... MELHOR PROJETO DO MUNDO NOVO SISTEMA Q PRODUZ HIDROGENIO UTILIZANDO SOMENTE AGUA.. NAO E ELETROLISE

[@marx875]

How to convert hydrogen to liquid hydrogen

[@sunlaser6587]

2 ways: use a 2 stage cryocooler or a hampson-linde approach. (search for helium liquifiers on google, i find ashmeads Helium liquifier a pretty interesing approac )

[@hansscholte5472]

For DIY you don’t need liquid; start with compressing it to 12 bar - 30 bar. You can use Propane tanks. Brings volume down a lot and is still very light.

[@mdrafiqul3358]

😀😀😀

[@johnauner671]

Not a big fan of Brown's gas I see.

[@dominicogallachoir4554]

Yeah the hydrogen and oxygen have so many more uses if you separate them. But I am curious if it could be economical to produce Brown's gas first and then separate it into H2 and O2 using some sort of gas membrane.