impressed current (1 Viewer)

[Halo189]

What is it in terms of redox reactions
I know that the inert acts as the anode and the protecting metal is cathode
I don't understand the reaction between them...

 

[Axio]

This is my understanding of it:

So for the corrosion of an iron pipe for instance the following occurs: 2Fe(s) -> 2Fe2+(aq) + 4e-

These electrons are forming iron hydroxides: O2 + 2H2O +4e- -> 4OH-

Applying a voltage causes the water to lose electrons at the inert anode: 2H2O -> O2 + 4H+ +4e-

and these electrons are used to convert the iron ions back into iron: 2Fe2(aq) + 4e- -> 2Fe(s)