Synthesis and Performance of Mannich Base Quaternary Ammonium Salt Acidizing Corrosion Inhibitor

A new type of Mannich base quaternary ammonium salt was synthesized as an acidification corrosion inhibitor. The inhibition performance of this corrosion inhibitor was evaluated in hydrochloric acid with different concentrations by static weight loss method. The results showed that with 0.1% inhibitor in 15% hydrochloric acid, 0.2% inhibitor in 18% hydrochloric acid and 0.5% inhibitor in 28% hydrochloric acid, the corrosion rates of steel N80 were all lower than 4 g·m-2·h-1 at 90℃. Polarization curves indicate that the corrosion inhibitor is a mixed inhibitor but mainly prohibits the anodic corrosion process, obeys the Langmuir adsorption isothermal equation and can spontaneously absorb on the steel surface by chemisorption.