Mitigation of sulfate reducing Desulfovibrio ferrophilus microbiologically influenced corrosion of X80 using THPS biocide enhanced by Peptide A

Tetrakis hydroxymethyl phosphonium sulfate (THPS) was enhanced by a 14-mer Peptide A, with its core 12-mer sequence mimicking part of Equinatoxin II protein, in the mitigation of sulfate reducing Desulfovibrio ferrophilus MIC (microbiologically influenced corrosion) of X80 carbon steel. Results proved that 50 ppm (w/w) THPS was sufficient to mitigate the D. ferrophilus biofilm, and its very agressive MIC (19.7 mg/cm(2) in 7 days or 1.31 mm/a), but not 20 ppm THPS. To achieve effective mitigation at a low dosage of THPS, biofilm-dispersing Peptide A was added to 20 ppm THPS in the culture medium. Sessile cell counts were reduced by 2-log and 4-log after enhancement by 10 ppb and 100 ppb Peptide A, respectively. Enhancement efficiency (further reduction in corrosion rate) reached 69% for 10 ppb Peptide A and 83% for 100 ppb Peptide A compared with 20 ppm THPS alone treatment, indicating that Peptide A was a good biocide enhancer for THPS. (C) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

In this study, Tetrakis hydroxymethyl phosphonium sulfate (THPS) was enhanced to mitigate microbiologically influenced corrosion (MIC) of carbon steel. The results showed that the addition of Peptide A can effectively enhance the mitigation effect of THPS at a low dosage.