Adsorption, Thermodynamic and Quantum Chemical Studies of 1-hexyl-3-methylimidazolium Based Ionic Liquids as Corrosion Inhibitors for Mild Steel in HCl

Materials

Motsie E. Mashuga¹  Lukman O. Olasunkanmi¹  Abolanle S. Adekunle¹  Sasikumar Yesudass¹  Mwadham M. Kabanda¹  Eno E. Ebenso¹ 

[1] Department of Chemistry, School of Mathematics and Physical Sciences, Faculty of Agriculture, Science and Technology, North-West University (Mafikeng Campus) Private Bag X2046, Mmabatho 2735, South Africa; E-Mails:

关键词: corrosion inhibition;    mild steel;    ionic liquid;    adsorption;    quantum chemical calculations;   

DOI  :  10.3390/ma8063607

来源: mdpi

【 摘 要 】

The inhibition of mild steel corrosion in 1 M HCl solution by some ionic liquids (ILs) namely, 1-hexyl-3-methylimidazolium trifluoromethanesulfonate [HMIM][TfO], 1-hexyl-3-methylimidazolium tetrafluoroborate [HMIM][BF₄], 1-hexyl-3-methylimidazolium hexafluorophosphate [HMIM][PF₆], and 1-hexyl-3-methylimidazolium iodide [HMIM][I] was investigated using electrochemical measurements, spectroscopic analyses and quantum chemical calculations. All the ILs showed appreciably high inhibition efficiency. At 303 K, the results of electrochemical measurements indicated that the studied ILs are mixed-type inhibitors. The adsorption studies showed that all the four ILs adsorb spontaneously on steel surface with [HMIM][TfO], [HMIM][BF₄] and [HMIM][I] obeying Langmuir adsorption isotherm, while [HMIM][PF₆] conformed better with Temkin adsorption isotherm. Spectroscopic analyses suggested the formation of Fe/ILs complexes. Some quantum chemical parameters were calculated to corroborate experimental results.

【 授权许可】

CC BY   
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