LAUSR

Abstract This work investigated the biofilm formation and microbiologically influenced corrosion (MIC) of a pipeline steel under cathodic protection (CP) in an extracted soil in solution with addition of sulfate reducing bacteria (SRB), Desulfovibrio desulfuricans . It was found that the application of CP did not affect the planktonic bacterial growth in the solution. The CP facilitated the bacterial attachment to the steel in this system, and a layer of biofilm formed on the cathodically protected steel, decreasing the CP effectiveness for corrosion protection. The CP potential of −850 mV vs. copper sulfate electrode (CSE) was not sufficient to protect the steel from corrosion in SRB containing media. Despite a further negative shift of the CP potential to −1000 mV vs. CSE was effective to control uniform corrosion of the steel, pitting corrosion still occurred under biofilm on the steel.