Acta Chimica Sinica ›› 2008, Vol. 66 ›› Issue (22): 2469-2475. Previous Articles     Next Articles

Original Articles

1-(2-羟乙基)-2-烷基-咪唑啉缓蚀剂缓蚀机理的理论研究

张 军a 胡松青a 王 勇*,b 郭文跃*,a 刘金祥a 尤 龙a

  

  1. (a中国石油大学物理科学与技术学院 东营 257061)
    (b中国石油大学机电工程学院 东营 257061)

  • 收稿日期:2008-04-24 修回日期:2008-06-26 出版日期:2008-11-28 发布日期:2008-11-28
  • 通讯作者: 郭文跃

Theoretical Investigation on Inhibition Mechanism of 1-(2-Hydroxyethyl)- 2-alkyl-imidazoline Corrosion Inhibitors

ZHANG, Jun a HU, Song-Qing a WANG, Yong *,b
GUO, Wen-Yue *,a LIU, Jin-Xiang a YOU, Long a
  

  1. (a College of Physics Science and Technology, China University of Petroleum, Dongying 257061)
    (b College of Mechanical and Electronic Engineering, China University of Petroleum, Dongying 257061)
  • Received:2008-04-24 Revised:2008-06-26 Online:2008-11-28 Published:2008-11-28
  • Contact: GUO, Wen-Yue

The inhibition mechanism of six corrosion inhibitors against H2S corrosions has been theoretically studied using quantum chemistry calculations, molecular dynamics simulations and molecular mechanics, and the inhibition performance was also evaluated. Front orbital distributions and Fukui indexes indicate that active reaction zones of the molecules are located in the imidazoline ring, which possesses three reactive sites of N(4), N(7) and C(8), enabling the ring to be multicenteredly adsorbed on metal surface. The calculated mono-molecular adsorption energies, membrane cohesive energies, distance of alkyl chains, and adsorption angles suggest that the stability and binding ability of the inhibiting membrane be enhanced with the increase of the alkyl length. When the number of carbon atoms in the alkyl chain is more than 13, the inhibitors can form a dense and high coverage hydrophobic membrane on metal surface, which can prevent efficiently the corrosive media in solutions from diffusing to the surface so as to slow down or even check the corrosion processes.

Key words: imidazoline, inhibition mechanism, quantum chemistry calculation, molecular dynamics simulation, molecular mechanics