[thaumasiotes]

Well, in a similar way to how you can't generate a negative ion without simultaneously generating a positive ion... how do you use the negative ion in a reaction without simultaneously using the associated positive ion in the same reaction?

[gsf_emergency_2]

Here's one way

https://en.wikipedia.org/wiki/Ion-exchange_membrane

Another, that you might be interested in, but it's more confusing

https://en.wikipedia.org/wiki/Proton-exchange_membrane

[gsf_emergency_2]

See the figure

https://www.fuelcellstore.com/introduction-ion-exchange-memb...

Each ion of salt participates in a different reaction