Influence on corrosion behavior of copper in marine iron-oxidizing bacteria

Abstract:

[Objective] Influence on corrosion behavior of copper in marine iron-oxidizing bacteria. [Methods] The effects of salinity and microbe on the corrosion behavior of copper were investigated by using open-circuit potential of electrode, polarization curves and electrochemical impedance spectroscopy (EIS). [Results] Results show that the analysis of scanning electron microscopy (SEM) indicated that the iron-oxidizing bacteria on the copper were rod. Electrochemical measurement results show that the control step for corrosion of copper in the culture medium for bacteria (IOB) in seawater is activation polarization process. The resistivity of seawater with bacteria is less 6 000 Ω·cm2 than that of without bacteria. It indicated that the retardation of the copper dissolution reaction in seawater with iron-oxidizing bacteria is small. [Conclusion] The presence of micro-organism (IOB) decrease the open circuit potential and activation polarizability of copper, thus speed up the corrosion process of pure copper.

Key words:Pure copper, Seawater, Iron-oxidizing bacteria, Electrochemical impedance spectroscopy