Action characteristics and mechanism of corrosion inhibitors in high temperature and high pressure complex aqueous environment

The corrosion problem of metal materials in high temperature and high pressure complex aqueous environment is the key to restrict the development of advanced technology and equipment in the field of energy, chemical industry and environmental protection. In high temperature and high pressure, especially in sub / supercritical water environment, the corrosion risk of materials is further increased. In order to effectively deal with this problem, as one of the important corrosion protection technologies, the application of corrosion inhibitors in the extreme environment of high temperature and high-pressure water phase has gradually become the focus. In this paper, the application status of inorganic and organic corrosion inhibitors in high temperature and high pressure and even sub / supercritical water environment is reviewed. The action characteristics and corrosion inhibition mechanism of common corrosion inhibitors (such as silicate, nitrite, imidazoline, quaternary ammonium salt, etc.) are discussed, especially the stability and efficiency of corrosion inhibitors in high temperature, high pressure and oxidizing media. The evaluation methods of corrosion inhibitors in different corrosive environments were analyzed, and the relationship between corrosion inhibitor performance and environmental conditions was proposed. It is pointed out that the stability of corrosion inhibitor, environmental adaptability and synergistic effect of compound use are the key factors affecting its performance. Although existing studies have revealed the good performance of corrosion inhibitors under normal temperature and pressure conditions, in the sub / supercritical water environment, the existing research on the high temperature stability and optimal use of corrosion inhibitors is still insufficient. In the future, the durability and environmental friendliness of corrosion inhibitors under high temperature and high pressure should be further explored to promote the development and application of new corrosion inhibitors. This review provides theoretical support for metal corrosion protection technology in high temperature and high-pressure water environment, and provides an important reference for technological development in the field of clean energy production and resource optimization.