2009/9/14 Abd ul-Rahman Lomax <a...@lomaxdesign.com>: > At 06:38 AM 9/14/2009, you wrote: > >> I'll wait for the detail of your ideas regarding the electronics, but >> it seems to me a few dollars worth of components would be sufficient >> for the computing and electrical "equipment", which could boil down to >> a tiny "USB key" with some relatively simple microcontroller and power >> electronics design work. A full blown computer plus a programmable >> power supply are certainly not necessary. > > "Programmable power supply" means that the electrolysis protocol can be > automatically followed. That's pretty simple. It's not different from the > "power electronics design work" you mention. By the way, I was primarily a > printed circuit designer for years, I still have the business, but the > design work is now being done in Brazil, I'm really rusty, but I have the > Altium software.
That's good. The design work could be simplified by starting from a reference design, what do you think of this one: http://ww1.microchip.com/downloads/en/DeviceDoc/51798a.pdf > >> Regarding current reversal: >> >> a/ no it's not stupid I don't think, indeed I seem to recall platinum >> works as a cathode substrate in those experiments (i.e. pits are >> produced). But you'll have to verify that the plating on the cathode >> does redissolve when it becomes an anode, things are not exactly >> symmetrical as Cl2 will have evolved from the solution in the first >> run I think. Anyone knows? >> >> b/ if it does redissolve, the electrode on the bottom doesn't have to >> be a permanent anode as you proposed, it could be an extension of one >> of only two electrodes (rather than three), which would thus occupy >> one side and the bottom, agreed? > > No, it should be separate, very simple to do, and it allows the "bottom" > anode to function with either polarity. Otherwise we would have to do the > de-plating run as a separate run. Good point. You're right, three electrodes is better. > The cathode doesn't care whether the > palladium in the electrolyte was added as a chemical at the beginning or was > dissolved from the anode. The bottom anode can be silver, it's just there to > scavenge palladium. > So we'd have two platinum wire electrodes which do alternate duty as > cathode/anode, and a bottom electrode which is probably silver foil, or some > other metal with silver plating, or maybe silver plating on the bottom of > the cell? Silver would be eaten away and would plate out onto the cathode, so this anode too would have to be Pt or Pt plated I guess. Which makes me wonder, Pd is close to Pt chemically, so why would it anodically dissolve in this particular electrolyte if Pt doesn't ? I know Pd does anodically dissolve in (at last some) acidic electrolytes, but in LiCl, I have no idea. And if it does, will it dissolve at a sufficiently high rate? Help, is there an electrochemist on the plane? Michel > Ideas about the chlorine would be useful. Could that be recycled? Or would > it limit the number of runs that could be done?