At 01:47 PM 3/16/2010, Jed Rothwell wrote:
Abd ul-Rahman Lomax wrote:
As Mr. Swartz pointed out, the concentration of oxygen at the
cathode is zero. So we have to imagine an oxygen bubble somehow
making it from the anode to the cathode, contrary to two flows, the
flow of deuterium gas is away from the cathode, but the flow could
carry oxygen from below the cathode to the cathode -- how would it
get down there? --
I know four ways to do this:
Yeah, they are pretty obvious. But as you implied, "Why do that?"
1. With intense mixing some oxygen may reach the cathode.
2. Pump the electrolyte through the cell, like the Patterson cell. I
believe the oxygen damaged the cathode beads in this configuration.
3. Put the cathode above the anode. The bubbles rise and attach to
it. I have seen people make cells with this configuration. Why they
did that, I cannot imagine.
4. With glow discharge electrolysis at intense heat some of the
water decomposes at the cathode. A mixture of hydrogen and oxygen
leaves the cell from cathode. Mizuno confirmed this by separating
the cathode and anode with a glass hood: a funnel placed with the
large end down over the cathode, with the anode on the outside. I
expect some of the oxygen reaches the cathode.
I can say that I thought of lining the bottom of the cell with part
of the anode, hoping that palladium that falls off the cathode might
end up redissolving. Probably wouldn't. This would have, of course,
caused oxygen to bubble past the cathode. I don't think it would have
done much of anything, though. I suspect that the bubbles would not
actually reach the cathode, they would merely get very close, and if
they did touch the cathode, I would expect immediate reaction, steam,
that would self-limit, the bubble would have to be actually trapped
in some way to totally react. I don't think it would get hot enough
to ignite what little mixture was formed of deuterium and oxygen; but
I suppose some bubbles of oxygen might merge with bubbles of
deuterium and form an explosive mixture. Small pop, that's all. The
deuterium trapped in the cathode is effectively deuterium at very
high pressure, and there is nothing there to oxidize it, it would
tend to repel any rapidly oxidizing material at the surface. It can't
explode from oxidation. And unless you get a lot of oxygen going to
the cathode, perhaps a cell could be designed to cause this, it would
slowly burn depending on the rate at which oxygen was being
generated, which isn't high. To melt palladium, the issue here, you'd
have to somehow accumulate this oxygen and keep it mixed with
deuterium without oxidizing (i.e., at below ignition temperature and
away from palladium as a catalyst, right?), or arrange for it to mix
later somehow, again without igniting but then it ignites all at once.
I don't get it, any way that this could happen if the cell is a
normal one where there is horizontal separation between the
electrodes, and nothing specially causing "intense mixing."
