新型高效双子咪唑啉缓蚀剂的研制

Development of a new high-efficient corrosion inhibitor based on gemini imidazoline

常规咪唑啉缓蚀剂在腐蚀防护方面有很多应用,但缓蚀效果不佳,且存在使用浓度高,形成缓蚀膜持久性差等问题,为此研发了一种新型高效环保的双子咪唑啉缓蚀剂。双子咪唑啉由两个烃链与两个头基通过刚性基团相连形成。采用电化学线性极化测试对缓蚀剂抑制CO_2腐蚀的性能进行了分析,并通过腐蚀失重实验评价了缓蚀剂形成膜的稳定性。实验结果表明:新型双子咪唑啉缓蚀剂在较低浓度下效果更好,双子型咪唑啉与脂肪酸混合比常规缓蚀剂的成膜性更好,乳化倾向也低于常规的缓蚀剂;新型双子咪唑啉比常规咪唑啉的表面活性高很多,临界胶束浓度比常规咪唑啉低数倍;新型双子咪唑啉缓蚀剂及其复配产品用量小、效果好、对环境污染小。

Conventional imidazoline corrosion inhibitors are widely used for corrosion prevention, but their corrosion inhibition effect is not good. And furthermore, they are used at a high concentration and the formed inhibition film is poor in persistency. In this paper, therefore, a new type of high-efficient and environment-friendly corrosion inhibitor, i.e., gemini imidazoline corrosion inhibitor was developed. It is composed of two hydrocarbon chains and two headgroups which are linked by a rigid spacer. Its CO2 corrosion inhibition performance was analyzed by using electrochemical linear polarization test, and the persistency of its inhibition film was evaluated by means of corrosion weight loss test. Test results show that gemini imidazoline corrosion inhibitor is more effective at a low concentration. The mixture of gemini imidazoline with fatty acid is better in film persistency and less in emulsifying tendency than conventional inhibitors. Compared with conventional imidazoline, gemini imidazoline is much higher in surface activity and several times lower in critical micelle concentration. Hence, the new type of gemini imidazoline corrosion inhibitor and its mixture are not only more effective in corrosion inhibition at a low concentration, but also more friendly to the environment.