Carbon steel corrosion inhibition in H2SO4 0.5 M medium by thiazole-based molecules: Weight loss, electrochemical, XPS and molecular modeling approaches

Carbon steel (CS) corrosion prevention is a significant problem in the industry. The development of an effective protection strategy is a popular research area. In this work, three thiazole derivatives (3-(2-methoxyphenyl)-4-methylthiazol-2(3H)-thione (P1), 3-phenyl-4-methylthiazol-2(3H)-thione (P2) and 3-(2-methyl-phenyl)-4methylthiazol-2(3H)-thione (P3)) were used in 0.5 M H2SO4 solution for CS corrosion mitigation. Weigh loss and electrochemical tests were used to assess their corrosion prevention effectiveness, while X-ray photoelectron spectroscopy was used to examine the steel surface (XPS). Electrochemical tests showed an inhibition efficiency between 90.1% and 98.4% for CS exposed to acidic solution containing 2 x 10(-4) M of the three thiazole derivatives. The three inhibitors were categorized as mixed type inhibitors since they inhibited both cathodic and anodic corrosion and they follow the Langmuir isotherm. XPS showed that inhibitor molecules formed a stable layer on steel surface through chemical and physical interactions. Furthermore, these experimental outcomes are well complemented from results analyzed by quantum chemistry calculations. Additionally, MD simulation outcomes helped in visualization of the adsorbed configuration of these compounds on the metal surface.

Automated summary

The study explored the corrosion mitigation of carbon steel using three thiazole derivatives in acidic solution, which exhibited high inhibition efficiency and the ability to form a stable protective layer on the steel surface. These inhibitors were classified as mixed type inhibitors and showed both cathodic and anodic corrosion inhibition.