Preparation and Properties of a New High-Temperature Acidified Corrosion Inhibitor

In order to improve the high temperature resistance of acidified corrosion inhibitor and meet the requirements of high temperature construction, a new type of high-temperature acidified corrosion inhibitor SJ-1 was obtained by using bis-Mannich base quaternary ammonium salts as the main agent, which were synthesized by adopting ethylenediamine, formaldehyde, acetophenone and benzyl chloride as reaction monomers, adding synergists such as propynyl alcohol derivative and antimony oxide, and optimizing by weight loss method. The corrosion inhibition performance of the inhibitor was tested at high temperature and high pressure. The results show that the inhibitor SJ-1 could achieve good corrosion inhibition effect when the dosage was only 2% (mass fraction) at 160 ℃. The corrosion rates of N80 steel sheet in 20% (mass fraction) HCl and soil acid were 30.84 and 28.33 g/(m²·h), respectively, which were far less than the primary level indexes in SY/T 5405-2019 standard. High-temperature acidified corrosion inhibitor SJ-1 could form a layer of dense hydrophobic film on the surface of N80 steel sheet to effectively inhibit the anodic corrosion process.