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Sam

Tue Aug 08 2006, 06:49PM

Registered Member #227 Joined: Mon Feb 20 2006, 10:47PM
Location: Cambridge Ontario, Canada!!
Posts: 127

I've got a little competition for everyone interested.
I have built some sort of device.
It is powered my 120vAC and pulls about 5 amps max.
http://s7.photobucket.com/albums/y298/benguy/?action=view&current=100_1471.flv
the video might explain some of it
http://s7.photobucket.com/albums/y298/benguy/?action=view&current=100_1472.flv

now I have 2 mots tied in parallel and 1/2 rectified with MO caps as ballast.
I'm olny using one side, (positive) at about 4 Kv? sound right?

Now I put the high voltage into the top of the plastic tube(open end) and the ground to the coffee can.(seled end)

when I fire it up bubbles form and sometimes a green flakey substance. from my experiance I'm told thats a chemical reaction. but when large bubles come from no-where in the center of the tube I believe thats hydrogen forming. I also get small amounts of bubbles forming at the HV electrode. at one point it "burps" and water and smoke and apparently fire comes out the end(I think the electrode was sparking in the water) then the water level drops below the electrode and it all stops.
I did put some salt in the water.

so guys whats happening?

...

Tue Aug 08 2006, 07:39PM

Registered Member #56 Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445

Not in a bad way, but did you have any idea what you were doing in that pic? Random high voltage leads laying around and salt water of all things is not a very safe combination.

I don't think your rig is capable of putting out more than 2kv or so, as paralleling things only increases current (not voltage). I also am curious as to how you managed to use a mo cap as a ballast with half wave rectification, as there is no ac voltage present (so no current should be able to flow through the cap). Is it possible that you managed to form a voltage doubler (like was in the mo to start with)?

In any case, I very much doubt that you had the full 4kv across the mess, as the conductivity of salt water is much to high for that.

Did the supply you made output a + or - voltage. If it was + then you were probably getting H2, if it was - then it was probably Cl2. The only way to tell is to hold a flame next to it, if it burns it is H2, if not is is probably Cl2.

Just whatever you, BE VERY CAREFUL

How hot did it get? With >500w going into it, I would imagine it would heat very quickly.

Marko

Tue Aug 08 2006, 08:18PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Yeah, halfwave rectifier won't work with a ballast cap- it will just charge up adn stop conducting.

Either your rectifier or oyur cap are dead or you explained something wrong there.

I doubt you are putting some heavy power into that water, especially after putting salt in.

Your supply voltage is way too high and you have 'impedance mismatch' on it. Power is defined I*I*R, you lowered the R and I is limited at some 1..1,5 A by ballast and leakage inductance.

2kV is probably way too much for some kind of electrolysis, you can put some nice current and power with few tens of volts with addition of some acid or salts.

You can put even more power trough ordinary plumbing water without additions with just rectified mains voltages.

The bubbles you get out are mostly hydrogen and chlorine. You get only half of hydrogen you would get without salt, since one hydrogen atom forms OH group with oxygen and sticks to Na ion.

NaOH is dangerous in high concetrations, destroys flesh, and is especially bad in eyes etc.

Chlorine is poisonous and stinky (altough I dooubt oyu can create enough of it to actually be dangerous) so it's not a good idea to do such electrolysis in closed rooms.

Dragging MOT's around for this is dangerous and just unneeded for such experiments..

Liam

Wed Aug 09 2006, 02:32AM

Registered Member #113 Joined: Fri Feb 10 2006, 01:40AM
Location:
Posts: 49

Try a way lower voltage. Five or 12 will work fine. Whatever source you have that's that low would work much better at a much higher amperage. Current is what you want, not voltage.

Tesladownunder

Wed Aug 09 2006, 12:34PM

Registered Member #10 Joined: Thu Feb 02 2006, 09:45AM
Location: Bunbury, Australia
Posts: 1424

Hydrogen and Chlorine as Firkraqq says.
Here is hydrogen/chloring ignition behind my MHD boat.
I guess the green flakey stuff is CuCl (white/insoluble) which decomposes to CuCl2 green/soluble. (need help from a bored chemist here

Peter

McFluffin

Sun Aug 13 2006, 02:45AM

Registered Member #119 Joined: Fri Feb 10 2006, 06:26AM
Location: USA
Posts: 114

I had an "interesting" experience with electrolysis that ended in a small plastic tank of hydrogen exploding on me a couple of years ago. I didn't get hurt, but my ears rang for a while. It sounds like you might get into the same sort of thing if you aren't careful since it sounds like it is randomly combusting.
Another good way to generate hydrogen is adding NaOH to alluminum (foil). It generates it pretty quickly, but it might have some NaOH in the vapor, so you might want to run it through some vinager or something to try to make it safer. I had some fun with this and water bottle rockets :) Maybe you can reuse the NaOH you get from electrolysis? Not sure how much is actually produced. Also, you won't have the oxygen mixed in, which makes it safer to work with until you actually want to burn it. Gets slightly more complicated to seperate it with electrolysis. I agree that thats CuCl2 thats probably forming.

Sam

Wed Dec 13 2006, 12:01AM

Registered Member #227 Joined: Mon Feb 20 2006, 10:47PM
Location: Cambridge Ontario, Canada!!
Posts: 127

back again and I've been learning. no more high voltage with salt water. WTF was I thinking!!!!! I have found more ways to make this fun gas. I now use H2SO4+H2O for my water mixture. still conductive but safer and at lower voltages. no more random combustions. YAY!! I also just use H2SO4+magnesium to make H2. all in all I find school helpful with being safer (and getting free stuff).

And I have to thank You guys for Your help.

Here is a video

Mod Edit: Fixed Double Post. It's 48 hours you have to wait.

electrolysis machine... drinking H2SO4+H20+CuO

Electroholic

Wed Dec 13 2006, 04:50AM

Registered Member #191 Joined: Fri Feb 17 2006, 02:01AM
Location: Esbjerg Denmark
Posts: 720

This guy designed a few electrolysis cell.

Now I DO NOT believe in none of those Ove*U**ty crap, found this site when i was doing research on barkyard foundry.

Steve Conner

Wed Dec 13 2006, 10:31PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Benguy, please don't post pictures of yourself pretending to drink your chemicals, it's not very responsible.

Sam

Sun Jan 14 2007, 10:52PM

Registered Member #227 Joined: Mon Feb 20 2006, 10:47PM
Location: Cambridge Ontario, Canada!!
Posts: 127

Steve Conner wrote ...

Benguy, please don't post pictures of yourself pretending to drink your chemicals, it's not very responsible.

whats wrong with drinking my H2O? lol it keeps me alive

JK JK, I'll keeps the pics to myself

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