The authoritative public forum
  for Metal Finishing since 1989
-----

Electrolysis of CO/CO2 and H2O

2003

Is there a way to effectively use electrolysis to separate Carbon and Oxygen? CO or CO2. If so, can I get a holler as to how please? Also, about how much power is needed to very quickly separate Hydrogen from H2O+NaCl? I have successfully used a 300Ma 16 volt solar panel charger to get a slow fizzing but am curious as to how many amps at 12 volt would be needed to get a good solid flow.

A curious budding inventor, Chris

Thanks for your time.

Christopher G.
- Loveland, Colorado, United States of America

---

I don't think it is possible to electrolytically separate carbon monoxide or dioxide into its elements.

As for electrolysis of water, remember that the power consumed equals the voltage times the current. So if you are trying for a worthwhile design, don't concede to 12 volts! Get the electrode spacing as small as practical and the electrodes as large as possible to minimize solution resistance, and try to get the voltage down.

The amount of hydrogen evolved is directly proportional to the current applied, according to Faraday's Law. One Faraday of current (96,485 amp-seconds) will release one gram equivalent weight of hydrogen, which is to say, one gram.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

To get hydrogen to outgass, all you have to do is to apply a voltage greater than the hydrogen overvoltage for that particular solution. Watch out with salt solutions as you will bring off more and more chlorine gas as you increase the voltage. Small amounts are no problem, but larger amounts are very bad for your body and anything that is made out of steel in the near vicinity.

James Watts
- Navarre, Florida
2003

---

I've been also wondering about electrolising CO2 - but haven't found anything of yet. However I have been electrolising water for some time. I first started when I was about 11 with NaCl and a twelve volt supply with a series of carbon rods from the inside of old D sized batteries. I quickly switched to NaOH as an electrolyte and found that it worked very well (tho' you do have to use fairly high concentration). Later I found out that the high voltage that I was using (12V) was way too high - and that was the reason for my solution steaming. It appears to be quantity of current that splits the water - not the total power input. I was lucky enough to find a Hydroxy gas generator at a scrap metal yard one day - I took it home and reconditioned it. It runs the electrodes at about 1.5 volts and 200 amps, it produces about 2 liters of gas per minute. The gas however is not separated - it has a certain amount of hydrogen in it and a certain amount of oxygen - and I'm led to believe it also has the majority is gasified water (HOH)(I'm not too sure what to think of this) but it does seem to have some validity. Apparently when you get a few hundred amps flowing through water - gas forms at the anode and cathode but gas also forms in the middle of the solution. If I decant the Hydrogen from the top of a tank and fill up a balloon with it the balloon will float like it has hydrogen in it, however when ignited the explosion is much more fierce that hydrogen by itself - so the oxygen has to be present within the molecules - I'll try find out more about it - I must recommend finding a machine like it sending balloons up in the air with fuzes is a really great way to have immature fun.

Brendon Tait
- New Zealand
2003

---

September 25, 2008

http://cat.inist.fr/?aModele=afficheN&cpsidt=16346191

Please check the above link for CO2 electrolysis

Good Luck!

Murgan

Murgan
- Dallas, Texas