Quantum chemical and experimental evaluation of the inhibitory action of two imidazole derivatives on mild steel corrosion in sulphuric acid medium
M. Ouakki,
M. Galai,
M. Rbaa,
A.S. Abousalem,
B. Lakhrissi,
E.H. Rifi,
M. Cherkaoui
Affiliations
M. Ouakki
Laboratory of Materials, Electrochemistry and Environment (LMEE), Faculty of Sciences, Ibn Tofail University, PB. 133-14000, Kenitra, Morocco
M. Galai
Laboratory of Materials Engineering and Environment: Modelling and Application (LMEEMA), Faculty of Sciences, Ibn Tofail University, PB. 133-14000, Kenitra, Morocco; Corresponding author.
M. Rbaa
Laboratory Agro-Resources, Polymers and Process Engineering, Faculty of Sciences, Ibn Tofail University, PB. 133-14000, Kenitra, Morocco
A.S. Abousalem
Chemistry Department, Faculty of Science, Mansoura University, El-Mansoura, 35516, Egypt; Quality Control Lab, Operation Department, Jotun, Egypt
B. Lakhrissi
Laboratory of Materials Engineering and Environment: Modelling and Application (LMEEMA), Faculty of Sciences, Ibn Tofail University, PB. 133-14000, Kenitra, Morocco
E.H. Rifi
Laboratory of Organic Synthesis and Extraction Processes (LOSEP), Faculty of Sciences, Ibn Tofail University, PB. 133-14000, Kenitra, Morocco
M. Cherkaoui
Laboratory of Materials, Electrochemistry and Environment (LMEE), Faculty of Sciences, Ibn Tofail University, PB. 133-14000, Kenitra, Morocco
The adsorption and corrosion inhibition properties of two imidazole derivatives namely, 2-(4-chlorophenyl)-1,4,5-triphenyl-1H-imidazole (IM-Cl) and 1,4,5-triphenyl-2-(p-tolyl)-1H-imidazole (IM-CH3) for mild steel in 0.5 M H2SO4 solution are studiedby electrochemical and computational calculations. The results obtained from the electrochemical methods show that IM-Cl and IM-CH3imparted high resistance and behave as mixed type inhibitors. Inhibition efficiency (IE %) increases with the increase of inhibitors concentration to attain 96 % and 91% at 10−3 M of IM-Cl and IM-CH3 respectively. EISdatais analyzed to model the inhibition process through appropriate equivalent circuit model. Thermodynamic and kinetic parameters controlling the adsorption process are calculated and discussed. DFT calculations are carried out at the B3LYP levels of theory with 6-31G (d,p) basis stein gas and aqueous phase for neutral and protonated forms. Quantum chemical calculations section of the study provides enough calculation and discussion on the relationship between corrosion inhibition and global reactivity descriptors.
