Effects of cathodic polarization on X65 steel inhibition behavior and mechanism of mixed microorganisms induced corrosion in seawater. (November 2022)

• Record Type: Journal Article
• Authors: Wang, Jian; Lv, Meiying; Du, Min; Li, Zhenxin; Xu, Ting; Li, Guannan
• Is Part Of: Corrosion science. Volume 208(2022)
• Publication Date: 2022-11
• Subjects: Microbiologically influenced corrosion -- Cathodic polarization -- Sulfate-reducing bacteria -- Iron-oxidizing bacteria -- Biofilm -- X65 pipeline steel; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2022.110670
• Languages: English
• ISSNs: 0010-938X

Abstract

Abstract: The laws of cathodic polarization on bacterial growth, biofilm formation and effects on the corrosion process of X65 steel were investigated when sulfate-reducing bacteria (SRB) and iron-oxidizing bacteria (IOB) are mixed using surface analysis and electrochemical measurements. Results indicate that insufficient potentials could not inhibit the localized corrosion, but increased the metabolic activities of bacteria. Effective protection could be achieved when the potential was negatively shifted to − 1050 mV vs. SCE. The effects of cathodic polarization on the precess of biofilms formation were also investigated. The − 1050 mV vs. SCE polarization potential could inhibit the biological activity of sessile bacteria, destroy the biofilm structure and inhibit the corrosion process induced by each biofilm. Highlights: Electrostatic repulsion from strong polarization inhibited bacterial adhesion and biofilm formation in SRB and IOB mixed bacterial system. Generation of OH - and deposition of Ca 2+ further inhibiting bacterial activity and adhesion. Strong polarization can lead to structural disruption of mature biofilms.