N-methyl-2-(2-nitrobenzylidene) hydrazine carbothioamide-A new corrosion inhibitor for mild steel in 1 mol·L-1 hydrochloric acid

The corrosion inhibition of mild steel in 1 mol·L?1 hydrochloric acid by N-methyl-2-(2-nitrobenzylidene) hydrazine carbothioamide (MNBHC) was studied using weight loss and electrochemical studies. Results obtained indicate that the inhibitor is effective in hydrochloric acid medium and the efficiency decreases with increase in temperature. Added halide additives improve the efficiency of the inhibitor. The AC impedance studies reveal that the process of inhibition is through charge transfer. Polarization studies indicate the mixed nature of the in-hibitor. From the thermodynamic, spectral and surface analyses the nature of adsorption has been found out. The adsorption of the inhibitor on mild steel follows the Langmuir isotherm.     

1-(2-Hydroxyethyl)-2-imidazolidinone as corrosion inhibitor of mild steel in 0.5 M HCl solution: thermodynamic,electrochemical and theoretical studies

The inhibition effect of 1-(2-Hydroxyethyl)-2-imidazolidinone (2-HEI) on mild steel (MS) corrosion in 0.5?M HCl solution was investigated at different inhibitor concentration and temperature by electrochemical experiments, such as linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and quantum chemical calculations. The inhibitor adsorption process on mild steel in 0.5?M HCl system was studied at different temperatures (20?°C–50?°C). Furthermore, the surface morphology of MS was also investigated with SEM in the absence and the presence of inhibitor. The adsorption of 1-(2-Hydroxyethyl)-2-imidazolidinone on MS surface is an exothermic process and this process obeys the Langmuir adsorption isotherm. The Quantum chemical findings are good agreed with the empirical data.