Title:
Electrochemical Chloride Extraction: Mechanisms & Long-Term Impact
Author(s):
David Whitmore
Publication:
Symposium Paper
Volume:
366
Issue:
Appears on pages(s):
132-140
Keywords:
cathodic protection, chloride-induced corrosion, concrete rehabilitation, corrosion mitigation electrochemical chloride extraction (ECE), electrochemical reactions, linear polarization resistance (LPR), steelreinforced concrete, structural durability
DOI:
10.14359/51749238
Date:
10/1/2025
Abstract:
Reinforced concrete is prevalent in construction for its strength and longevity. However, it can be susceptible to corrosion when exposed to chloride ions, particularly in areas affected by de-icing salts and marine environments. The technique known as Electrochemical Chloride Extraction (ECE) helps combat this corrosion by pulling chlorides away from the reinforcing steel and raising the concrete's pH around the steel. This paper examines the technique's development, the electrochemical reactions, and its effects on corrosion rates. Although ECE can dramatically lower chloride-induced corrosion, immediate post-treatment measurements often reveal increased corrosion rates as the passive oxide layer is re-established. A comparison of Linear Polarization Resistance (LPR) measurements before and after ECE illustrates the technique's effectiveness.
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