06-26-2008, 12:04 PM
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#81 (permalink)
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silverknight
I have been looking in a lot of electroplating books for hydrogen generation info. In plating, they are trying to supress it, but still.
First thing: The minimum voltage you need to generate hydrogen depends on the metal your electrodes are made from. Sounds crazy! The key phrase here is "hydrogen overvoltage"
2: Hydrogen is produced by the flow of current (electrons) thru the solution. So production depends on amps, and it is not tied to volts, or watts, or energy. (someone tell me I'm wrong here if you think so)
3: Now some bad news: The best choice for electrodes is platinum, which has been electroplated with more platinum (with a trace of lead) to make (wait for it ) Platinised Platinum Electrodes. Note the spelling is with an S not a Z.
platinised platinum - Google Search
This is done afaik to make more surface area on the electrodes for hydrogen generation.
4: Good news! The hydrogen overvoltage of platinum can be as low as .03 Volts according to a electroplating book from 1963. This paper:
http://www.pubmedcentral.nih.gov/pic...9&blobtype=pdf
shows a graph of overvoltage that varies between 1.6 to 1.9 millivolts!!!! (it changes as a H2 bubble gets free)
5: I found (and cannot find again ) a web page that gave data on conductivity of soluitons. It said 2 things: The maximum conductivity depends on WHAT you dissolve in the water. It also depends on HOW STRONG the solutilon is. And again here is a crazy thing: too MUCH or too LITTLE concentration gives a poorer conductivity. There is an ideal sweet spot for best conductivity.
This web page suggests that production of H2 can be enhanced by ultrasonic bombardment to strip the H2 off the electrodes as it is made.
Sonoelectrochemistry : Chlorine, hydrogen and oxygen evolution at platinised platinum
So my conclusions: The most efficient generation of H2 is from a cell with platinised platinum electrodes, with a very large electrode surface area, in a solution that has a material and concentration which gives the best conductivity. The power to the cell should NOT be 12 volts. It should be reduced to much, much lower voltages, and deliver maximum current. Sound like a transformer to me.
To add to what some have said, I have been guilty of mixing up "Browns Gas" generation with adding H2 from a tank. I guess I see them as interchangable (and maybe they are not!)
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06-26-2008, 01:36 PM
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#82 (permalink)
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Quote:
Originally Posted by JamesLaugesen
Very low percentage of hho, working on the claim that even a very small amount makes gasoline "burn like hydrogen".
I plan to power my test electrolyser (fused at 10amp) off the headlight circuit, so I can switch it on/off easily from inside the car and do multiple test runs with & without the generator running.
Hopefuly I can prove those claims false, then take it from there
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interesting...Could probably help emissions at least, if not anything else. I wonder how much better it would be than other fuel additives. Anywho, good luck and I look forward to seeing your results!
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06-26-2008, 01:42 PM
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#83 (permalink)
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Quote:
2: Hydrogen is produced by the flow of current (electrons) thru the solution. So production depends on amps, and it is not tied to volts, or watts, or energy. (someone tell me I'm wrong here if you think so)
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To clarify, I do not think it possible to produce "Browns Gas" using less energy then you get from re-combusting it. If perpetual motion machines worked, we would have had them long ago.
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06-26-2008, 02:56 PM
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#84 (permalink)
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Harebrained Idea Skeptic
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Quote:
Originally Posted by ttoyoda
2: Hydrogen is produced by the flow of current (electrons) thru the solution. So production depends on amps, and it is not tied to volts, or watts, or energy. (someone tell me I'm wrong here if you think so)
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Yes, it's the current flow that produced the electrolysis, but that current is produced by voltage across the electrodes -- as voltage varies, so will current. Thus, it is indeed "tied to volts," although volts is not what you're ultimately interested in.
Quote:
Originally Posted by ttoyoda
5: I found (and cannot find again ) a web page that gave data on conductivity of soluitons. It said 2 things: The maximum conductivity depends on WHAT you dissolve in the water. It also depends on HOW STRONG the solutilon is. And again here is a crazy thing: too MUCH or too LITTLE concentration gives a poorer conductivity. There is an ideal sweet spot for best conductivity.
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That's not a "crazy thing" -- nearly all chemical reactions have ratios that are optimum. If you're using table salt (sodium chloride, not "a salt," which is not the same thing) as an electrolyte, consider what would happen if you put one grain of salt into 100 gallons of water -- not much change in the base conductivity. Conversely, if you added so much salt that the mixture was nearly dry, that would approach the properties of salt.
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06-26-2008, 03:58 PM
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#85 (permalink)
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A couple things.
Quote:
2: Hydrogen is produced by the flow of current (electrons) thru the solution. So production depends on amps, and it is not tied to volts, or watts, or energy. (someone tell me I'm wrong here if you think so)
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Volts, amps, and watts are linked with Ohms Law. V=IR (Volts=I[amps]*R[resistance]) and also Watts=Volts*Amps.
There is an optimum voltage for low heat electrolysis and I think it is like 1.2-2 volts per cell which is similar to lead acid batteries. This is difficult to do in one container. I am still trying to figure out a good compact design
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The best choice for electrodes is platinum
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spot price is 2000+/ounce
Stainless Steel plate covers from Lowes are $1.50
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It also depends on HOW STRONG the solutilon is
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This is true and it is one way to control the amps needed by adding solution until desired amp draw is achieved.
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Sound like a transformer to me.
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You will have to modify your setup to use an AC alternator because transformers only work on AC not DC.
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To add to what some have said, I have been guilty of mixing up "Browns Gas" generation with adding H2 from a tank. I guess I see them as interchangable (and maybe they are not!)
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Do not store HHO in any kind of tank. That is a very bad idea. You would be storing everything necessary for an explosion minus ignition. All you would need is a backflash and it would be all over. Only store pure H2 as this will not explode because it has to mix with the outside air first.
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If you're using table salt (sodium chloride, not "a salt," which is not the same thing) as an electrolyte,
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Not a good idea to use salt because a byproduct is chlorine gas which is toxic. You want to use an electrolyte with no byproducts. KOH and NaOH. Potassium or Sodium Hydroxide. You could also use some acids like H2SO4 (Sulfuric acid) but I am not totally sure on the acids.
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06-26-2008, 04:46 PM
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#86 (permalink)
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Quote:
Originally Posted by SVOboy
HHO is controversial enough without us arguing in circles with no personal experience or data to go on.
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From a top level view, HHO gas certainly should burn, and if your engine is tuned to take advantage of it, it should be "stoking the fires of combustion".
Fuel in = energy out
More fuel in = more energy out
Here's the rub: It takes electricy to make that 'brown's gas'. The systems I have seen being sold or plans for the DIY'er all use electrical current generated by your engine turning the alternator. Without some external source of 'free' electricy or 'free' hydrogen, it can't work. An electric car doesn't keep charging itself if you add a generator driven by the electric motor, ok, it won't charge itself enough to sustain battery charge
I want it to work too, but let's check the math on this... it takes work to generate electricity, electricity to make 'Brown's gas' from water. Agreed? Agreed.
That's not free electricity mind you, your engine just worked that much harder to produce those flowing electrons to run the HHO generator, right? Right. It took hp away from driving the wheels. If your alternator wasn't asked to do more work, run the HHO generator, it would just coast along for the ride. Take that 'fuel' and add it to the gasoline. Fuel + Fuel = more work out than just <one> fuel alone. Sadly, my physics instructor is right ONCE AGAIN (dam him)... physical science allows no free lunch.
So...
Fuel (gasoline)= Work (wheels go round and round)
AND
Fuel + a little more fuel = Work + a little more work
take your pick.
Unless you believe in free energy, understand that the energy it takes to produce Brown's gas is equal to or greater than the power adding boost it could possibly give at the rear wheels.
It gets worse, ICE's are only 25% efficient, so at best you could only net a fraction of that added power, to the rear wheels. Either that or physical science is completely full of $hit, and someone invented a perpetual motion device. My money is on science and my crusty old physic prof.
Oh, I almost forgot... on a side note, the guys selling these systems are working too. They market, purchase parts and assemble the kits, box and ship, paperwork and taxes to pay. No free lunch for them, either. Dam!
There's another rub: Like any business for profit model, Car companies and oil companies historically buy up the competition to enhance their own market share, and why wouldn't they? My dad worked on a clutch system that lasted 3x longer than current (1959) clutches of the day. The Trolley systems in 1920's California were bought up by BF Goodrich and promtly dismantled, for instance, so consumers would buy more cars and needs tires. That clutch project was killed by the spare parts arm of the company. HOWEVER... That doesn't mean their has ever been a working 200mpg Poge carburator <http://www.snopes.com/autos/business/carburetor.asp>, or perpetual motion machine.
Facts mixed with marketing confuse us all, sometimes enough to make a convincing story with an interesting subplot. Throw in a few black hat wearing villians and you have the stuff legends are made from.
Last edited by metromizer; 06-26-2008 at 06:51 PM..
Reason: typos, added a couple tid bits
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06-26-2008, 05:41 PM
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#87 (permalink)
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I know their are different types of HHO generators, but none of you have mentioned the one designed by Stanley Myers. It is the one I am going to try and duplicate as it seems to produce the most amount of gas with the least amount of power.
If you guys are interested I can post the information and blueprints I have regarding his design which uses Stainless steel pipes. Let me know ..
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06-26-2008, 05:49 PM
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#88 (permalink)
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penny pincher
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Stop it! you're "blinding me with science" already! Just make it work, good luck to you all!
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06-26-2008, 05:56 PM
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#89 (permalink)
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Quote:
Originally Posted by kevlar
Stop it! you're "blinding me with science" already! Just make it work, good luck to you all!
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You got it!
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06-26-2008, 06:48 PM
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#90 (permalink)
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Just to clarify, a lot of what I am suggesting would need a lot of parts and work and money. Not to mention, more though!
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You will have to modify your setup to use an AC alternator because transformers only work on AC not DC.
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I was thinking switching power supply at high frequency. Have you ever seen one of those big weller soldering guns that has a "heater" clamped into two posts? I think those are a single shorted secondary turn of a transformer. That creates enough amps to get a 10 guage or so copper element hot enought to melt solder. How many amps is that? Obviously the core material is wrong, but still.
Quote:
Volts, amps, and watts are linked with Ohms Law. V=IR (Volts=I[amps]*R[resistance]) and also Watts=Volts*Amps.
There is an optimum voltage for low heat electrolysis and I think it is like 1.2-2 volts per cell which is similar to lead acid batteries. This is difficult to do in one container. I am still trying to figure out a good compact design
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I agree with all the equations. The graphs in the links suggest lower production at lower voltages. So there might be some sort of tradeoff, perhaps you have found it, but it seems to me that .03 volts times 1000 amps would give 100 times more hydrogen than say 3 volts at 10 amps, both are 30 watts. You need a lot of cell plate area and big buss bars to get a flow of 1000 amps though, obviously it is a significant project to make such a cell. Clever idea on your part to put cells in series, you bypass the whole problem of large currents. How about cutting off the top of a dead car battery and remove the guts, for your case? You get 6 compartments that way.
I understand why you want to use SS. You will need an higher overvoltage, but of course you are not going to get Pt for your first try, I was just looking longterm. Be aware that apparently the chromium from the SS will leach out into the solution, due to the electorplating going on, so don't dump that in your yard.
Quote:
Do not store HHO in any kind of tank. That is a very bad idea. You would be storing everything necessary for an explosion minus ignition. All you would need is a backflash and it would be all over. Only store pure H2 as this will not explode because it has to mix with the outside air first.
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I agree completely, and it is good you pointed that out to everyone who might read this.
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That's not a "crazy thing" -- nearly all chemical reactions have ratios that are optimum. If you're using table salt (sodium chloride, not "a salt," which is not the same thing) as an electrolyte, consider what would happen if you put one grain of salt into 100 gallons of water -- not much change in the base conductivity. Conversely, if you added so much salt that the mixture was nearly dry, that would approach the properties of salt.
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Well when you put it that way it is obvious. Durr. Boy am I dumb.
There are some solutions which do lead to the lowest resistance, though, even at the best ratio. I think the web site said nitric acid was the best, but that is not practical these days after 9/11 and what with the cost of platinum.
Quote:
Yes, it's the current flow that produced the electrolysis, but that current is produced by voltage across the electrodes -- as voltage varies, so will current. Thus, it is indeed "tied to volts," although volts is not what you're ultimately interested in.
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I claim that if (as) the surface area of the plates in the cell is increased, I can increase the current without increasing the voltage, but I am STILL LIMITED by the "hydrogen overvoltage" of my electrode material. So theoretically I can generate a lot of gas with low watts by making the cell physically very very large. Now maybe that is not practical for other reasons, because I have no idea what I mean by "very, very, large" .
Or if I put "many" seperate generator cells in series, per silverknight, I use the current "more than once", and now I have "reasonable" currents and "reasonable" voltages. (waves hands )
Finally, we ARE mixing up two things here, and maybe we should not- The generation of "browns gas" which is one technical problem
-Can engine combustion be made more efficient with addition of just hydrogen, or "browns gas"?, which is a different problem.
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