Mitigating Sulfate-Reducing Bacteria-Induced Corrosion of Pure Copper in Simulated Oilfield-Produced Water Using Cetylpyridinium Chloride

This study explores the corrosion behavior of pure copper in simulated oilfield-produced water and evaluates the inhibitory effect of cetylpyridinium chloride (CPC) on microbiologically influenced corrosion (MIC). Weight loss tests, potentiodynamic polarization, and pitting analyses revealed that sulfate-reducing bacteria (SRB) activity significantly accelerated corrosion, with the maximum pit depth reaching 7.54 µm in the absence of CPC—approximately 1.83 times greater than under abiotic conditions. The introduction of CPC substantially reduced corrosion rates and pit depths, with maximum pit depths decreasing to 2.97 µm, 1.11 µm, and 1.02 µm at 10, 50, and 80 mg/L CPC, respectively. CPC inhibited SRB biofilm formation, metabolic activity, and corrosion product accumulation, achieving an inhibition efficiency of up to 89% at 80 mg/L. These findings highlight CPC’s dual role as a biocide and a corrosion inhibitor, offering a promising approach to controlling MIC in oilfields and similar industrial environments.