The use of electrochemical techniques for the investigation and monitoring of microbiologically influenced corrosion and its inhibition – a review

Abstract

The background of several electrochemical techniques -recording of the corrosion potential E corr , electrochemical impedance spectroscopy (EIS), electrochemical noise analysis (ENA) and recording of potentiodynamic polarization curves -has been discussed and examples of the use of these techniques in studies of microbiologically influenced corrosion (MIC) and MIC inhibition have been presented. These examples range from the use of the polarization resistance R p and the noise resistance R n in corrosion monitoring in a sewer environment and a gas production field, respectively, to the application of EIS and ENA in the evaluation of the interaction of bacteria with protective coatings on steel exposed to natural seawater (NS). A more detailed analysis based on EIS and ENA of Corrosion protection of Al 2024, mild steel and brass in artificial seawater (AS) by bacteria such as B. subtilis, B. licheniformis, E. coli and Shewanella has been presented. Determination of the changes of R p and R n as well as E corr allows to propose appropriate mechanisms of MIC inhibition. These mechanisms have been confirmed in the case of S. algae by recording of anodic and cathodic potentiodynamic polarization curves after exposure to AS containing the bacteria for extended time periods.

Streptococcus Sanguis Biofilm Architecture and Its Influence on Titanium Corrosion in Enriched Artificial Saliva

“…Figure 4 a shows the Nyquist plots of titanium immersed in enriched artificial saliva with S. sanguis , it is clearly found that all of the diagrams are a part of the imperfect semicircles and this can be attributed to the frequency dispersion [ 28 , 29 ]. The fact that diagrams have a depressed semicircular appearance shows that the corrosion of titanium is mainly controlled by a charge transfer process.…”

Bactericidal and Anticorrosion Properties in PVK/MWNT Nanocomposite Coatings on Stainless Steel

“…EIS was employed to evaluate the corrosion behavior of the PVK–CPN coated films (PVK and PVK/MWNT) on SS coupons. EIS is considered to be a powerful tool in probing charge transfer phenomena and interfacial ion transfer on films 31, 32. The corrosion resistance of the bare SS, PVK coated SS, and PVK/MWNT‐modified SS were analyzed after immersion of the films in 0.5 M NaCl for 7 d. All samples show capacitive behavior as presented in the semi‐circle plot (Figure 6).…”

Use of an Electrochemical Split Cell Technique to Evaluate the Influence of Shewanella oneidensis Activities on Corrosion of Carbon Steel

“…These activities exert considerable control on the chemistry of fluids immediately adjacent to the metal surface [ 10 , 14 , 16 , 17 ]. Microbial activities can also limit the contact between O 2 or other corrosive compounds and the metal surface, inhibiting corrosion processes [ 18 – 24 ]; however, heterogeneous biofilms may induce corrosion through formation of differential aeration and concentration cells on the surface of the metal [ 25 – 29 ]. Given the diversity of mechanisms by which microbial activities may enhance and/or inhibit corrosion, it is necessary to develop a clear mechanistic understanding of the factors involved in MIC.…”