Corrosion Inhibition Performance of 2-Mercaptobenzimidazole in Sweet Oilfield Conditions

2-mercaptobenzimidazole (MBI) has been shown to be an effective inhibitor of carbon-steel corrosion in aqueous solutions of both hydrochloric and sulfuric acid. Here, we extend such studies to examine its performance in conditions mimicking a sweet oilfield environment. Linear polarization resistance is employed to determine corrosion rates in the presence or absence of MBI as a function of both solution temperature and CO2 partial pressure. Results demonstrate that MBI effectively inhibits corrosion within the parameter space explored i.e. solution temperatures of 30°C and 55°C and total applied pressures of 1 bar and 20 bar. Potentiodynamic polarisation measurements are presented to further characterize interfacial corrosion chemistry. X-ray diffraction and scanning electron microscopy are applied for post-immersion substrate characterization.