Controlling C-steel dissolution in 1 M HCl solution using newly synthesized ρ-substituted imine derivatives: Theoretical (DFT and MCs) and experimental investigations

Abstract

• ρ- substituted imines as C-steel corrosion inhibitor. • Δ N of SB-OCH 3 is higher than SB-CH 3 . • SB-OCH 3 enhances the R ct of C-steel to 374.9 Ω.cm 2 . • Adsorption type of tested imine compounds was physicosorption. • SB-OCH 3 resisted C-steel corrosion under severe conditions. Corrosion is an inevitable process, but its control is the goal of the researchers using organic inhibitors. So, newly successfully prepared ρ-substituted imine compounds namely;( E )- N,N -dimethyl1-4-((tolylimino)methyl)aniline (SB-CH 3 ) and ( E )-4 (((4methoxyphenyl)imino)methyl)- N,N -dimethylaniline (SB-OCH 3 ) have been fabricated to control the C-steel dissolution in 1M HCl. Hammett concept and theoretical calculated parameters were applied to predict the adsorption affinity of the prepared imine derivatives and the laboratory gravimetric and electrochemical tests accompanied with surface analysis tools were conducted to confirm these predictions. The fabricated imine compounds suppressed the C-steel reaction with efficacy of more than 90 %. The SB-OCH 3 exhibited higher adsorption affinity than SB-CH 3 and they acted as hydride C-steel corrosion inhibitors and followed Langmuir isotherm. The Δ G a d s * values of C-steel reactions in presence of these compounds were around -37 kJmol −1 . The inhibition performance of SB-CH 3 and SB-OCH 3 was function in their concentrations, molecular weight, and solution temperature. SB-CH 3 and SB-OCH 3 suppressed C-steel reaction at high temperature and the SB-OCH 3 showed highest efficiency (76.8%) at 60 °C. The activated thermodynamic parameters of C-steel reaction in existence and nonexistence of 1 × 10 −3 M imine compounds were calculated and discussed. The comparison findings with the previously published compounds confirmed the superiority of the understudied imine derivatives.