How does the current flow in an electrolytic system?

In an electrolytic system, the flow of current is best described as moving from active to noble through the electrolyte. This principle is rooted in the electrochemical behavior of metals in which the more reactive (active) metal will corrode preferentially when connected to a less reactive (noble) metal, leading to current flow through the electrolyte solution where ions can migrate.

During the process of corrosion, electrons flow through the metallic path from the active metal to the noble metal. Concurrently, in the electrolyte, positively charged ions are produced from the anode (the active metal) and move towards the cathode (the noble metal). This dual movement of electrons in the metallic circuit and ions in the electrolyte collectively constitutes a complete electrical circuit, which is essential for electrochemical reactions to occur.

Understanding this behavior is critical in corrosion control and mitigation strategies, especially when designing cathodic protection systems.