The synergistic inhibitive effect of polymer and gemini surfactant on the hydrochloric acid corrosion of mild steel

摘要

The corrosion inhibition behavior of the polymer-surfactant in mixed solution of the synthesized green cationic i.e., ethane-1,2-diylbis(N,N-dimethyl-N-dodecylammoniumacetoxy)dichloride, gemini surfactant referred as (12-E2-12) and a polymer sodium carboxymethylcellulose (NaCMC) in HQ solution was studied by electrochemical technique, computational and MD simulation study. The studied system (12-E2-12/CMC) inhibited the corrosion of mild steel in 1M HQ solution and the extent of inhibition was dependent on concentration. 12-E2-12/CMC is mixed-type inhibitor, according to results of corrosion potential obtained from potentiodynamic polarization. The decreasing values of C_(dl) and increasing values of R_(ct), obtained during EIS measurements, suggests formation of protective layer over the mild steel surface. SEM micrographs displayed clearly different morphology in presence of studied inhibitory system confirmed the existence of an adsorbed protective film on the mild steel surface. Quantum chemical calculations and MD simulation were applied to elucidate the adsorption behaviour and inhibition mechanism of studied system.