The corrosion behavior and mechanism of carbon steel induced by extracellular polymeric substances of iron-oxidizing bacteria

• DOI: 10.1016/j.corsci.2016.10.025
• Publication Date: 2016-10-24T06:00:17Z
• Authors: Hongwei Liu; Tingyue Gu; Muhammad Asif; Guoan Zhang; Hongfang Liu
• Keywords: 13. Climate action; 0103 physical sciences; 01 natural sciences

Abstract In this work, the corrosion behavior and mechanism of carbon steel induced by extracellular polymeric substances (EPS) extracted from an iron-oxidizing bacterium culture were studied using surface analysis and electrochemical measurements in 3.5 wt% NaCl solutions. Results of electrochemical measurements showed that 7 day-old EPS at 240 mg L −1 inhibited the corrosion of carbon steel, especially after the EPS solution was heat treated to deactivate the enzymes in the EPS. However, 7 day-old EPS at much higher and much lower concentrations accelerated corrosion. Furthermore, 14 day-old EPS and 28 day-old EPS at 240 mg L −1 also accelerated corrosion.