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Re: New kind of CO2 kit ( electrode-based
Chiao Lun wrote:
>I saw a CO2 kit at my LFS the other day and the cover said it put two
>electrodes in the water and one of the electrodes would be made of carbon.
>The Carbon electrode has a negative charge and the carbon reacts with the
>oxygen produced while the other electrode bubbles hydrogen.
>The device is marked 150W and costs US$200
>Is such a device possible?
Hmmm, I'd be suprised if there was significant oxidation of the carbon
electrode to CO2 by the generated O2. I remember the experiment back in
school were we used carbon rods salvaged from carbon-zinc batteries as
electrodes to split water into H2 and O2. We were not looking for
consumption of the O2 generating electrode as it was oxidized, nor did we
ever hear that it would be consumed by the O2. Perhaps it was, but I bet
most of the bubbles on the electrode were oxygen.
How much carbon is in the electrode, and how fast is it consumed? You won't
get any more carbon out, in the form of CO2, than you put in, in the form
of carbon electrodes.
Compare the electrode size to the amount of carbon in two cups of sugar
used for brew. You can buy a lot of sugar for $200.00, there's no
electrical costs, no electrodes to replace, and no danger of electrocution.
Also, 150 watts is a lot of power. At this rate the carbon electrode should
be consumed very very quickly. If it is not consumed quickly then you are
most likely wasting a lot of power truning water into H2 and O2. Imagine
the size of a battery that could generate 150 watts for one hour. That
gives a very rough idea of the amount of chemistry needed to move that many
electrons. By the same token, if you have that many electrons pumped into
the generator, it should give you an idea of the amount of chemistry you
could alter. If this things works well, 150 watts is going to eat carbon
electrodes voraciously. I would guess at least several pencil size pieces a