Study on the Synergistic Inhibition Effect of Imidazoline and Mercaptoethanol on the Corrosion of Carbon Steel in Tarim Oilfield

The inhibition effect of oleic-based imidazoline (OIM) and mercaptoethanol (ME) on the corrosion of carbon steel in carbon dioxide saturated 3.5% sodium chloride solution was investigated by weight-loss method, electrochemical techniques and scanning electron microscopy (SEM) analysis. Results indicate that compared with individual addition of OIM or ME, better corrosion inhibition effect can be obtained when OIM-ME mixture is added. The OIM-ME mixture can inhibit both anodic and cathodic reactions, significantly alleviating the corrosion of carbon steel. Morphologies analysis also confirms the excellent inhibition effect of OIM-ME mixture. Thus, a conclusion can be drawn that there is notable synergistic inhibition effect between OIM and ME, and the optimal molar ratio of OIM and ME is 1:3.