Characterizations of the biomineralization film caused by marine Pseudomonas stutzeri and its mechanistic effects on X80 pipeline steel corrosion

Microbiologically influenced corrosion (MIC) of steel generates a corrosion product film, which can also be called biomineralization film. It is critical to understand the structure of biomineralization film since it dominates the corrosion behavior of metal. In this work, Pseudomonas stutzeri (P. stutzeri) was isolated from seawater, and the biomineralization film caused by marine P. stutzeri was characterized by Transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), etc. The mechanistic effects of the biomineralization film on X80 pipeline steel corrosion were also investigated. The results indicate that the minerals are mainly composed of nano Fe3O4 and FeOOH, according to TEM and XRD results. The particle sizes of biominerals are below 10 nm. This work also provides an insight strategy to prepare nanomaterials by MIC caused by P. stutzeri. In addition, P. stutzeri can grow well with CO2 as a carbon source and iron as an electron donor. The corrosion rates (CRs) of specimens are closely related to the structure of biomineralization film. The CRs increase with the decrease of initial cell concentration. P. stutzeri with an initial concentration of 10(7) cells/mL can promote the formation of a compact biomineralization film with a thickness of 145.8 +/- 4.8 mu m, leading to corrosion inhibition with a CR of 0.058 +/- 0.008 mm/y. But some corrosion pits can be observed due to the formation of small anodes. Electrochemical impedance spectroscopy (EIS) data show higher impedance values and two time-constants, which imply the formation of a compact biomineralization film. (C) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

This study investigates the effects of biomineralization film caused by marine P. stutzeri on the corrosion of X80 pipeline steel. The results show that the film is mainly composed of nano Fe3O4 and FeOOH, with particle sizes below 10 nm. The research provides insights into preparing nanomaterials through MIC caused by P. stutzeri.