Most efficient way to Electrolisize water into H2 and O2

[akcapr]

personally i think paint is alot simpler and easier to use

[Insane]

It would be perfectly safe if your hydrogen is not contaminated by O2 inside of electrolyser.

 

That's a better idea. Since air is about 30% oxygen, the flame will burn without a separate supply of oxygen. Just capture the oxygen in a separate bottle and breath it in for fun and profit.

[calbiterol]

personally i think paint is alot simpler and easier to use

 

Depends on what you're using it for. I use imaging software mostly for heavier stuff, like picture-editing or web media... And let me tell you, patching up someones face and looking realistic is darn near impossible in paint.

[akcapr]

if ur just trying to draw a diagram paint is perfect

[calbiterol]

Yeah, then I use paint. Except when I want transparency, but then I still start out in paint. Wow, we are on a heck of a tangent...

[Insane]

It's amazing how easy it is to hijack a thread.

[Gregoriev]

WTF!? I accedentaly hit an "N" instead of a stupid T and you all go hyjacking my thread as some stupid Pain VS photoshop debate?

 

I am working with explosive stuff here!!!! Geeze...

 

Now where can a guy buy some NaOH on the cheap? And don't say internet...

[raivo]

Buy some cheap drain cleaner that does not contain hypochlorite ( most of these are just solution of NaOH ) or ask someone who makes soap at home or boil solution of Na2CO3 together with lime.

[Gregoriev]

okay dude....that's just not cool. I only want the high grade stuff for my electrolysis.

 

quick question though:

 

How far into the tube should the electrodes be for maximum electrosizing? too far and the circuit may not complete well enough, too exposed and hydrogen and oxygen may leak out into the housing creating a bubble of explosive gas to collect and probalbly detonate. I am thinking 1-2 cm into the individual h2 and o2 electrolysis tubes.

 

and also, the NaOH will not break down over time right? I am counting on this, because once i seal the housing, the only way in would be through the water intake tube, and it would be a bitch to have to check and preportion the NaOH in there properly.

 

one last thing, what is the right preportion of NaOH to water that would produce the kind of ultra fast high production electrolsizing i am looking for? I want this thing to convert a Gallon of water into H2 ande O2 every 25-30 minutes. I know that will take alot of units, but if each is as perfect as possible it might just work.

[raivo]

I want this thing to convert a Gallon of water into H2 ande O2 every 25-30 minutes. I know that will take alot of units, but if each is as perfect as possible it might just work.

 

This is completely unrealistic. To decompose 1 mole (18g) in 30 minutes you need more than 50A current. To decompose 1 gallon you need more than 10 000 A.

 

Most of your questions can not be answered remotely. You have to do some experimenting and computing to be successfull. Do similar electrolysis in small flask several times with different setup and measure anything you need to know. Do not expect anyone can just tell you everything.

 

1..2cm is probably not enough 5...7cm is more realistic but you have to test this some way because this depends on several factors, such as liquid movements on working electrolyser. 10% NaOH solution may be good choice, chemical stability of NaOH is generally very high but this also depends on many factros, such as exact composition of electrode material or various contaminants that find way into your electrolyser. If you want to succeed, you have to do lot of experimenting, all that can be easily explained has already been explained here.

[jdurg]

Over time, NaOH will corrode glass and eat away at it, thus weakening anything in the system made of glass. Also, NaOH and NaOH solutions will absorb carbon dioxide from the air to form solutions of NaHCO3.

[Gregoriev]

Okay, the properties of NaOH seem to be pretty good. The electrolysizers will be totally CO2 free, since they will be sealed and filled 100% with only water.

 

The effects of H2 and O2 electrolysis on copper remains to be seen...

 

And what I am talking about is having multiple units running at 20-30 amps. I am stabbing in the dark here, but depending on the ouput vs the imput, the ammounts of water I actually need electrolysized remain unknown. But I know for a fact I will need alot.

 

In reagards to not having answers to my questions...seriously?! There is NO known research out there thats published in regards to how to electrolysize water as quickly and efficiently as possible??? I have looked myself and found nothing...but surely someboy here knows something in regards to where I can find the detailed information I need.

 

[Gregoriev]

What the!? why are there no more posts???

 

COME ON!!! Nobody has anyhing else to say!? It has been several days!

 

No comments on the pic, design, nothing!?

[ffsjoe]

one thing to say is that you should be very careful with that many amps

[akcapr]

ur desine is fine for thew most part and is probably as efficient as ull be able to get.

[Guest mayhan]

Though you've received a lot of useful information, you seem to be a little shaky on some of what exactly is going on in your fizzing pot. Make sure that you get as good a groundng as you can before just plugging in power to some random brew--bad stuff can happen.

 

As you probably know, electricity run through water causes it to break up, but water is a very poor conductor and this is slow and expensive. The name of the game is to get a salt, acid, or base to ionize (separate molecules into positive and negative ions) in order to speed up the reaction. Various things work.

 

The problem that's the biggest issue at hand is that in running electricity through an ionic aqueous solution will cause the ions to react with the water, the anonde and cathode, and the reaction vessel. There's a reason that nearly everything in a lab is glass (silicon based) or ceramic (carbon based)--they're less reactive. You need to be very aware of how each new checmical you introduce is going to affect the reaction.

 

People leaving posts in this thread have often disagreed. What hasn't been pointed out is that they could all be correct! For example, carbon is NOT inert (it's in the molecules of probably every cell of your body), but it won't react with water alone. One guy said his graphite electrodes wore out very quickly, and one said his never wore out. They are both correct, because depending on what solution you're using, the carbon in the rods may or may not react.

 

These considerations are very imporant to understand not only for efficieny, but for safety. For example, table salt (NaCl) works great for increasing the conductivity of water (much better than baking soda or powder), but in a saturated solution, electrolysis releases chorine from the solution more readily than oxygen. This eventually results in the release of Cl2, an extremely deadly gas. Actually, the first ever use of fatal chemical weapons on a massive scale was in WWI (1915), when the Germans piped chlorine gas into the wind blowing over French trenchs at the Second Battle of Ypres. That's what you'd be making in your garage! Leave it brewing overnight, and you'd better get a canary.

 

You've said things like, you thought stainless steel wasn't "supposed to rust." What you need to remember is that rust is just vernacular for a common chemical reaction between water and iron. Stainless steel is an alloy of iron and chromium (alloy is kind of like a solidified solution). It resists oxidation in water alone, but when you're adding whatever chemicals, different stuff will happen depending on A) the solution and B) the composition of the electrodes you use. In a nutshell, stainless steel isn't always stainless in electrolysis, and you need to be sure that the byproducts created aren't too horrible. The reason platinum is so dang expensive is that it's considered a precious metal. Why? Because it stays shiny all the time--in other words, it reacts with very little!

 

I noticed you plan to use PVC pipe to protect and channel your annode/cathode. The chemical formula for Poly-Vinyl Chloride is C2H3Cl; it's obviously got chlorine in it. Who knows how that's going to affect things? Have you thought about what you're going to use as a reaction vessel? Obviously the annode and cathodes are going to be much more in danger of participating in the reaction than the vessel, but if you just put this in a 5 gallon plastic bucket... Who knows?

 

I have heard that H2SO4 (sulfuric acid--like from a car battery) is one of the best things you can use for the electrolysis of water because it increases conductivity a lot and doesn't participate actively in the reaction (not jacking your electrodes, not needing replenishment, and not creating negative byproducts), but a big bucket of battery acid is just a bad idea on general principle--especially if that bucket is of the 5 gal plastic variety...

 

In the short run, you might be fine with whatever solution, but on the scale you're talking about production, bad stuff could happen eventually. For example: if you use NaCl for the salt, you create H2 at the cathode (+), and O2 and Cl2 at the annode (-), but what happens to the Na? Sodium is a metal that doesn't boil off at low temperature. What happens is that it ionizes with the decomposing water in the form of OH (hydroxide). Having sodium and hydroxide ionized in water means that you have... (wait for it...) NaOH--Sodium Hydroxide. That, my friend, is the active ingredient in oven cleaner and Drano--one of the most corrosive bases you can get.

 

So not only are you bubbling off what the ATF would classify as a chemical weapon, you're doing it in a pot of Drano. If you didn't realize this and let your brew sit unattended for a day before returning... Assuming you managed to avoid dying initally when you breathed the cloud of chlorine, you might reach into the reaction vessel or splash it in your eyes. Way bad! Again, my point is that you need to understand what's going on.

 

The other guys who posted seem to have had a lot of experience dicking around with this stuff--I would suggest asking them exactly what they used. It's not good enough to say "my graphite rod worked great." You need to know it worked great in a whatever percent solution of whatever chemical in a container made out of whatever, you know? Was it tap water or distilled water? Etc.

 

To summarize, you need to take a step back--you don't want to rush into this. I won't bother to lecture you on the obvious (trying to mass produce hydrogen and oxygen in a home environment with very little understanding of Chemistry is an accident waiting to happen; oh--and don't even get me started on your plan to "create large ammounts of hydrogen and oxygen to be stored in high capacity tanks"...), but I will say that you need to slow down and take things step by step. I would try several different solutions with several different electrode materials, etc., on a small scale and figure out what is the best efficiency to safety ratio. Check your vessel, electrodes, and piping system for "deterioration," or "rust," or "corrosion," and your solution for clouding or precipitates (crap at the bottom), because if any of these are happening, something foreign to your desires is participating in a chemical reaction. This could be merely annoying, or really bad/dangerous depending.

 

Oh--one last piece of advice--don't use copper; that's dumb. I understand your point about the surface area, but you've got bigger fish to fry right now. You can always go back later and make your electrodes longer or drill them or mash them or whatever, but for now just try to make a good reaction without killing yourself. Anyway, varying your electrical parameters will make a zillion times more difference in things than wasting time designing and building special electrodes. Also, copper is too reactive; it won't likely make anything toxic, but your electrodes will shred (even without a solution). Ever seen a really old penny? And that's just from water--an ionic solution will hyper-accelerate that reaction. Again, in the short run you'd be fine, but when you're talking about doing things on a massive, scale copper is a very poor choice.

[akcapr]

great explanation mayham, but ur making it sound like synthesizing Ag2C2! its really not that bad, minute amounts of chlorine are produced. Even if you can smell it, that doesnt mean dangerous concentrations are in the air, since Cl2 is easily picked up by the nose. Also, the NaOH created isnt bad eaither. The quantities will be very minute, and too minute to hurt the skin (only the eyes). and mayhem, correct me if im wrong, but im guessing youve never electrolyzed water bfore.

[Guest mayhan]

It's been years since I have, and it was in a lab environment. I remember the best results we got were from sulfuric acid. I definitely bow to you guys as far as experience goes on the electrolysis front; I'm just trying to be the voice of reason. There's a lot of advice flying around and it doesn't sound to me like Greg really knows what he's doing.

 

From what I've read about the Cl2 is that initially the water dissolves almost all of it and all is well. Later though, when the water is saturated, it starts to bubble out pretty quickly. When he's talking about mass producing this stuff, it indicates he may leave it alone for good stretches. What if he does it in the spare room or something? He also talked about sealing containers--a good mouthful of Cl2 upon opening a container would definitely suck. You're right though--luckily Cl2 has a strong odor. Maybe I'm over cautious.

[Guest mayhan]

Oh,

 

Sorry I'm an ass; I didn't notice there were 4 pages... A lot of my notes were already addressed. After reading the other 3 pages here are a couple extra notes:

 

-->Stay away from Fluorine compounds. F is at the far right of the periodic table, just short of the inert gasses. This means that it is as highly reactive with just about everything as is possible (because it wants to gain that last valance electron for stability). You probably wouldn't get much beyond just trace amounts, but if you manage to produce much Hydrofluoric acid you'd be in a world of hurt--that stuff is freakishly dangerous--it can even eat glass! One time in a lab at my university a guy was working with some and was wearing super thick chemical gloves. What he didn't realize is that it had a tiny hole in the pinky finger of the right hand...

 

A little background chem-- If I remember correctly, (some of this chem might be off, but it's generally solid) when you brush your teeth, the sodium fluoride in the toothpaste reacts with the calcium carbonate in your teeth to make calcium fluoride (I believe that's what enamel--the hardest thing in your body--is made from). It's a super strong mineral that coats your teeth and acts as a barrier against bacteria. The same thing happens when fluorine is allowed to react with the calcium carbonate in bone, but that's less desireable...

 

Anyway, hydrofluoric acid is so caustic that it cauterizes nerve endings like a laser as it reacts--you can't feel it eating your flesh. So this guy gets done with the experiment and takes off the heavy gloves to find all the flesh on his pinky missing. This of course sucks, but it gets worse--the hydrofluoric acid had leeched into his bone and reacted with the calcium carbonate to turn his entire finger into calcium fluoride. It's green and looks like jade, so you can imagine that'd be pretty creepy. Had to get it amputated. That story is pretty inapplicable to your case, it's just a bad-A story. Moving on...

 

-->I haven't managed to notice the diagram of you're design that people keep referring to, but the idea of mixing and igniting H2 and 02 for your flame isn't a very good one. For the purposes of your endless flame experiment the H2 will do just as well. Think about it--bunsun burners, cigarette lighters, propane torches, barbeque grills. They all vent the gas through a nozzle that allows atmospheric oxygen to mix with it; thus, it burns at a decent rate. The only time you see the addition of oxygen into that equation is when you want to create a ton of heat.

 

I'm a welder, and you use 02 in cutting torches: you turn on the acetylene and light it, then slowly turn on oxygen until the mix is as hot as you want it. To do this you need a nozzle made of special material (and of course one that doesn't mix the gases until the very very end!), or the end of the aparatus will melt from the heat. Now, keep in mind that an oxyacetylene torch is hot enough to cut just about any metal you'd want to, and the hydrogen/oxygen reaction is quite a bit hotter than that! It's actually one of the hottest reactions there is--that's what they use to power the space shuttle. Accidents like Challenger are a perfect example of how volatile it is.

 

But I digress--point is, for the eternal flame experiment H2 is perfect. Add 02, and you are quite likely to end up with an explosion, even if it's a small one. Barring that worst case scenario, it will burn really hot. Too hot for a nozzel made out of anything you'd have around to sustain.

 

-->The responses to your comment about blowing up the balloon were pretty telling--you're all a bunch of pyros, aren't you! Actually, I blow stuff up for a living, so I'm no exception. That having been said (and harking back to my notes above on the heat and power of a H2/02 reaction, your balloon idea is an amazingly bad one. Unless your backyard is a hell of a lot bigger than mine, you wouldn't be able to put a safe amount of distance between yourself and the big boom. If you're going to do something like that, what you'd want to do is put a long fuse inside before you stop up the pressure. An H2/02 ballon is very light and you would want to light the fuse (5-10footish?) and let that thing go up and away (and not into the powerlines)!

 

Speaking of which, I knew a guy who made a hydrogen plant in his back yard and somehow managed to fill a weather balloon with the stuff. Attaching a small charge with a timer on it, he released it in a remote desert area away from town (I think it was AZ). The way he tells it, he wishes he had used a much longer timer! Apparently it blew up completely different from any explosion he had ever seen (in real life or the movies) or was expecting.

 

As we all know, H2 only burns in the presence of 02. The pressure in the balloon, when punctured and lit by the charge caused H2 to be thrown outwards in really weird patterns. Plus, it only burned as it came into contact with the O2, so it didn't go boom all at once. He said it threw weird tentacles out all around itself, that turned and twisted at really odd angles, and that the fireball was huge--taking up nearly his whole range of vision and knocking him down. Everytime he thought it was done, another tentacle would race out of the main fireball and shoot off it's own lines. Said it scared the crap out of him because anyone within 100 miles could have seen it and it looked like it was about to descend on his truck! Keep in mind that adding O2 would have made such an explosion instantaneous and would have caused a massive shockwave that H2 just can't. In case you weren't kidding--don't try that in your backyard.

 

-->On to electricity: for experimentation purposes the ideal would be a variable power supply. It looks like a square metal lunch box with at least one dial. Sometimes they have meters too. A nice one will have a knob to vary voltage and one to vary amperage (with a coresponding meter for each) at the very least. You can undoubtably pick one up on Ebay for pretty cheap; I've got 2 and have passed on quite a few more I've seen at local surplus sales. That would give you maximum testing ability. After you know about what voltage and amperage you're looking for you can use the correct permanent power supply.

 

-->Regarding graphite rods, the best source would be a chemical supply house, but barring that I would go to a welding shop. You can get "carbon rods" to use in a carbon arc torch (this is an electrical welder, but instead of striking an arc from metal to metal with the intention of fusing the 2, you strike the arc from carbon rod to carbon rod--it makes a ton of light and heat). Get the smallest size they sell. I can't vouch for trace elements in the carbon though. Chem supply house is a much better idea if you're going to do it right (I.E. without pencils).

 

-->NaOH: I believe if you buy Drano crystals (not the liquid stuff), it's pure NaOH. Then you just put it in water to make your solution. Had a dumbass friend in high school that used to make Drano bombs--adding ripped up bits of aluminum foil to the crystals, then dumping it all in a glass jar of water, seal, shake, throw. The NaOH solution reacts with the aluminum in the foil and makes H2 (and a lot of pressure).

 

Problem is, if you shake too long, you blow your hand off and pepper the rest of your body with glass shards, and if you don't shake long enough it won't go off soon (sits around like a time bomb). BAD IDEA! I could tell you a story about not shaking long enough, a lady walking her dog, and it's excellent sense of smell, but the statue of limitation probably hasn't passed yet...

 

-->On your ambitious (some would say insane) production timescale, I agree with raivo--do a lot of experimenting on a small scale and see what works and what doesn't. I would also add SLOW DOWN! This stuff is too dangerous to rush, if you're going to do it at all. Also keep in mind that each circuit breaker in a house is designed to support 15amps of current; approaching 20 will throw the breaker. If raivo is correct in his computations that "To decompose 1 mole (18g) in 30 minutes you need more than 50A current," that means you would have to run machines off three separate circuit breakers to even accomplish this. Otherwise, it would just trip the breaker.

 

-->As per your request for data on "research out there thats published in regards to how to electrolysize water as quickly and efficiently as possible," I'm sure it's out there, but not via Google. The thing about this technology is that it's archaic. The reason you can only find references to experiments for science classes is that these days that's all it's good for. Oxygen and Hydrogen production hasn't used these technologies for decades; they are made via other means.

 

The research you want undoubtedly exists, but it was probably conducted back in the 1700's during the enlightenment and is now considered useless from a practical standpoint. I could be wrong; the way to go about it would be to go to the library of a major univerisity and search really really old scientific journals for some trace. Frankly, I think your cohort's advice coupled with careful experimentation on a small scale will turn up the answers you want, and it will be good for you. People generally don't want information like that floating around accessible, because it's not useful for anything good--just morons like us who want to blow stuff up.

[jdurg]

Actually, in an oxyacetylene torch the acetylene is only there to heat up the metal. When you turn the oxygen on, you are supposed to turn the acetylene off. The high heat and the excess of oxygen actually cuts right through the metal as the metal is instantly oxidized.