Insights into corrosion inhibition behavior of multi-active compounds for X65 pipeline steel in acidic oilfield formation water

Inhibition behavior of new designed inhibitors for X65 steel in CO2 saturated oilfield formation water containing acetic acid has been investigated by electrochemical measurements, surface characterization, scanning vibrating electrode technique, rotating electrochemical quartz crystal microbalance, and X-ray photoelectron spectroscopy. It is found the inhibition efficiency can exceed 95% for each inhibitor at a concentration of 3 × 10−4 mol/L. The inhibitor film exhibits a compact and uniform structure, which is more effective for the corroded rather than freshly prepared steel surface due to the facilitation of chemisorption. The active centers of inhibitor adsorption mainly focus on N, S atoms, and conjugation system.