烷基咪唑离子液体缓蚀剂缓蚀机理的理论研究  

Theoretical Studies of Mechanism of Alkylimidazolium Ionic Liquids as Corrosion Inhibitors

作　　者：周维中 田国才[1] 

机构地区：[1]昆明理工大学省部共建复杂有色金属资源清洁利用国家重点实验室,云南昆明650093

出　　处：《昆明理工大学学报（自然科学版）》2017年第3期1-9,共9页Journal of Kunming University of Science and Technology(Natural Science)

基　　金：国家自然科学基金项目(51264021;50904031);云南省中青年学术技术带头人后备人才培养项目(2011HR013)

摘　　要：采用量子化学计算与分子动力学模拟相结合的方法研究了氯化1-丁基-3-甲基咪唑(A)、氯化1-己基-3-甲基咪唑(B)、氯化1-辛基-3-甲基咪唑(C)、1-辛基-3-甲基咪唑硫酸氢盐(D)、1-辛基-3-甲基咪唑乙酸盐(E)、1-辛基-3-甲基咪唑三氟甲磺酸盐(F)六种离子液体对盐酸溶液中铁腐蚀抑制的微观机理,并对缓蚀性能进行了评价.量子化学计算发现,这六种离子液体分子的反应活性区域主要集中在阳离子的咪唑环和阴离子的Cl、O原子上,而且缓蚀效率随烷基链长的增加而增加,离子液体F的缓蚀效率最高.分子动力学模拟发现离子液体的阳离子主要以咪唑环、阴离子主要以含氧基团吸附且覆盖在金属铁的表面,形成一层保护膜阻碍腐蚀介质与铁表面相互作用而起到缓蚀作用.六种离子液体的缓蚀效率顺序为F>E>D>C>B>A,与实验研究结果相一致.The corrosion inhibition mechanisms and performances of six ionic methy - limidazolium chloride （A）, 1 - hexyl - 3 - methylimidazolium chloride liquids including 1 - butyl - 3 - （B）, 1 - octyl - 3 - methyl - imi- dazolium chloride （ C）, 1 - octyl - 3 - methylimidazolium hydrogen sulfate （ D）, 1 - octyl - 3 - methylimidazolium acetate （E）, and 1 -octyl -3 -methylimidazolium trifluoromethanesulfonate （F）at iron surface in hydrochloric acid are analyzed and evaluated. It shows that the reactive regions of these six ionic liquids molecules are concen- trated on the imidazole of cations and the C1, O atoms of the anions from quantum chemical calculations. The inhi- bition efficiency is increasing with the increase of alkyl chain length of ionic liquids. The best corrosion inhibitor in present study is ionic liquid F. From molecular dynamics simulations, it is found that imidazole rings of the cations and oxygen - containing groups of the anions in ionic liquids are covering iron surface as a protective film, which hinders contact between the iron surface with corrosion media. The order of inhibition efficiency of six ionic liquids follows as F 〉 E 〉 D 〉 C 〉 B 〉 A, which is consistent with experimental results.

关 键 词：缓蚀剂 离子液体 缓蚀机理 量子化学计算 分子动力学模拟 

分 类 号：TG174.42[金属学及工艺—金属表面处理]