Electronic Circuits and Projects Forum

18th August 2006 05:56 AM

I just increased voltage, how much both the anode and cathode are releasing gas? Before only the cathode is releasing gas.

Heres an Off topic Question:

If I have Aluminum as the cathode and Anode, will I get Aluminum Sludge or Aluminum Oxide. I figure if the anode oxidizes, and the cathode reduces, I can use use graphite as the cathode and put Aluminum on the Anode.

18th August 2006 06:16 AM

Originally Posted by HarveyH42

Second, once the balloon is filled, how bouyent will it be? I know that hydrogen is lighter than helium, and will float well, but oxygen is heavier. So how much weight will this balloon lift? Enough for a timer, battery, and ignition circuit?

A mole of hydrogen/oxygen from electrolysis would weigh,

H2 * 66% * 2 = 1.33g
O2 * 33% * 32 = 10.66g
Total 12g

A mole of air would weigh
N2 * 72% * 28 = 20g
O2 * 28% * 32 = 9g
Total 29g

So H2/O2 mix would lift 17g per mole. A mole of gas is 22Ltr

I think the above is correct.

Mike.

18th August 2006 09:57 AM

Originally Posted by Overclocked

If I have Aluminum as the cathode and Anode, will I get Aluminum Sludge or Aluminum Oxide. I figure if the anode oxidizes, and the cathode reduces, I can use use graphite as the cathode and put Aluminum on the Anode.

i have done these type of electrolysis long back. and if i remember correctly , you won't get aluminium oxide , but you will get aluminium hydroxide which forms as a white substance.

18th August 2006 10:26 PM

If you really want large amounts of Hydrogen, then just mix aluminum and lye. You know, the drain cleaner. I have never done this, so PLEASE BE CAREFULL! I know that it is a very quick and effective way to make A LOT of hydrogen, VERY QUICK! You better have a BIG balloon! Seriously, though, this is a fast and simple way to make it.

18th August 2006 10:30 PM

Originally Posted by Marks256

If you really want large amounts of Hydrogen, then just mix aluminum and lye. You know, the drain cleaner. I have never done this, so PLEASE BE CAREFULL! I know that it is a very quick and effective way to make A LOT of hydrogen, VERY QUICK! You better have a BIG balloon! Seriously, though, this is a fast and simple way to make it.

That doesnt work. I tired it with draino, and AL foil. Nothing. Doesnt even boil, but I used liquid stuff (which is 5% Lye). Ive read I have to use crystal draino (thats atleast 65%)

19th August 2006 01:28 AM

5% is nothing compared to 65%. I would suggest getting the actual brand "Lye". That is what it says on the bottle. If not, i think Hydrogen Peroxide mixed with "Active Yeast" will do the trick. My old science teacher used this method to make her hydrogen, before she thought about buying it in bottles.

23rd August 2006 07:06 AM

Originally Posted by Overclocked

That doesnt work. I tired it with draino, and AL foil. Nothing. Doesnt even boil, but I used liquid stuff (which is 5% Lye). Ive read I have to use crystal draino (thats atleast 65%)

Man...aluminium is very reactive but it is very quickly covered with with a chemical inert oxide.

23rd August 2006 03:34 PM

You tried it? How much did it put off? If that is the problem, with the chemical covering it, then all you would have to do is cut the aluminum into tiny strips.

23rd August 2006 05:23 PM

Aluminum corrodes fairly rapidly in either an acid OR a base. That pretty much shoots to hell any hope for a productive electrolyte.

25th August 2006 11:30 AM

Hi,

I can't claim to have read every single post in this topic, but I just thought I'd add my little bit. In my experience electrolysis is a pretty slow way to make H2, with pure water and a low voltage (<200). A few things to speed it up:

Add H2SO4 to the water, it souldn't get used up in the reaction (so you can just add more water and you've still got the sulphuric acid in there). This will increase the conductivity of the water, more current flowing for a given voltage.

Increase surface area of electrodes. My chemistry teacher once put Iron rods into accid for a while until they became pittted, then coated them in a silver compound (some cheap jewelery chemical stuff?) so they didn't corrode during the process.

Also, this is unconfirmed, I've never tried it, but apparently, chopped DC can increase the speed of the reaction (much like using ultrasonics). Off the top of my head, in certain 'pseudo-science circles', the frequencies are 600Hz (well not 'hertz, but cps), 610, 12Khz, and 40-42Khz. I did see this process on an episode of 'equinox' on CH4 in the UK, where guy used a small motorbike battery, a circuit, and produced enough H2/O2 to make a small implosive welding flame (3 inches). As I said, unconfirmed, and I haven't seen any evidence for this, so god knows how he actually did it (mains power from hidden cable?).

My £0.02, keelynet has lots of info on this, most of it anecdotal, but interesting none the less.

Good Luck.

Blueteeth

Electronic Circuits and Projects Forum

Making Hydrogen