The monitoring of the formation and destruction of corrosion inhibitor films using electrochemical noise analysis (ENA)

Electrochemical noise analysis (ENA) was used to monitor continuously the film formation and destruction processes of carbon dioxide (CO2) corrosion inhibitor imidazoline. Imidazoline is an inhibitor base which is most commonly used for protecting oil wells, gas wells and flowlines from CO2 corrosion. Experimental results show that the trends in the electrochemical noise effectively followed the inhibitor film formation and destruction processes. Electrochemical noise data analysis strongly suggests that ENA is a practical technique in the continuous monitoring of inhibitor firm performance and in the evaluation of inhibitor film persistency. Electrochemical noise resistance (R(n)) is confirmed to be strongly correlated to polarization resistance (R(p)) or the sum of charge transfer resistance and inhibitor film resistance (R(c) + R(film)), although the theoretical background and data analysis methods require further investigation. ENA is also shown to be a convenient method for continuous corrosion rate monitoring. Copyright (C) 1996 Published by Elsevier Science Ltd