新疆油田高盐含氧体系缓蚀剂的性能研究

In order to solve the problem of oxygen corrosion in oilfields, a Schiff base corrosion inhibitor TMCAM with multiple adsorption sites was synthesized using trans-p-methoxycinnamaldehyde and 3-aminobenzoic acid as the main raw materials. Firstly, the corrosion inhibition performance of different concentrations of Schiff base corrosion inhibitor TMCAM on Q235 steel in 60 ℃ oxygen-containing oilfield simulated water was evaluated by the dynamic weight loss method. The results showed that when the concentration of TMCAM was 60 mg/L, the corrosion rate of Q235 steel was 0.062 4 mm/a, meeting the site requirements. When TMCAM concentration was 100 mg/L, the corrosion rate of Q235 steel was only 0.036 8 mm/a, and the corrosion inhibition rate could reach 90%. Secondly, the characterization techniques such as scanning electron microscopy, electrochemical method, and contact angle test were used to evaluate the corrosion inhibition performance and analyze its corrosion inhibition mechanism. The results showed that TMCAM was a mixed type corrosion inhibitor with a bias cathode, and the adsorption ability between TMCAM molecules and Fe was strong. Moreover, TMCAM could form a hydrophobic film on the steel surface, reducing the contact time between oxygen-containing wastewater and pipelines, slowing down corrosion and protecting pipelines. Finally, molecular simulation technology was used to analyze the relationship between the corrosion inhibitor’s corrosion inhibition performance and the molecular configuration of the corrosion inhibitor from a theoretical perspective. The results showed that the molecular structure of TMCAM had a strong adsorption capacity, which was higher than that of Schiff base corrosion inhibitors reported in the literature.