Can you make an electrophoresis battery?

[michaelm700]

Can you immerse an electrolyte in an external electric field such that the ions are separated to a point that you could introduce electrodes and produce current in a load solely by virtue of the established charge distribution without electrode chemical interaction or galvanic potential as shown in the picture below?

That is, electrons on the anions will travel through the load and reduce the cations on the other side of the container. For instance, say the electrolyte was salt water. Would the Cl- ions oxidize to chlorine gas at the anode and furnish electrons to reduce H+ producing hydrogen gas at the cathode. The process would continue by virtue of the applied electric field and continued Na, Cl dissociation to replace the lost Chlorine? The potential for current flow is caused by the charge distribution from the field rather than a galvanic potential.

 

[Borek]

Many ways to skin that cat ;)

Try to think this way: where would the energy to light the bulb come from?

 

[michaelm700]

I'm thinking from heat of the fluid perpetuating the dissociation as ions are netrualized.

 

[Borek]

Are you suggesting it is a perpetuum mobile?

If so, thermodynamics tells us it won't work and you don't have to waste time analyzing it any further.

 

[michaelm700]

This is where I can't connect the dots. How does it violate the 2nd law? If the electrolyte is heated, the increase in entropy will provide an increase in available Gibbs energy for work after paying the enthalpy price for dissociation for NaCl. I would assume this would be added to the kinetic energy of the ions which on average would tend to be influenced by the field.

I was thinking one the ions made contact with the electrode, current would flow like discharging a capacitor. Is there some way to show chemically that electrons could not do this?

 

[Borek]

If the electrolyte is heated

By what?

You have an external, static electric field. Battery it is connected to is the only source of energy. You can't modify this field, nor use energy it has, from the inside, being isolated from the external electrodes.