Corrosion inhibition of 316 stainless steel in 2M HCl by 4-{[4-(dimethylamino)benzylidene]amino}-5-methyl-4H-1,2,4-triazole-3-thiol

Abstract

Abstract The corrosion inhibitory action of a Schiff base, 4-{[4-(dimethylamino)benzylidene]amino}-5-methyl-4H-1,2,4-triazole-3-thiol (DBAMTT), on 316 stainless steel (316 SS) in 2M HCl was studied using potentiodynamic polarisation technique, electrochemical impedance spectroscopy(EIS) and weight-loss measurements. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to analyse the surface morphology of the alloy. The effect of inhibitor concentration from 25 to 2000 ppm was investigated in the temperature range 30–50 °C. Results showed that DBAMTT was an efficient mixed-type inhibitor. The inhibition efficiency was found to increase with the increase in inhibitor concentration and increase in temperature. The adsorption of DBAMMT on 316 SS obeyed Langmuir isotherm. Evaluation of various thermodynamic parameters suggested that, the adsorption is by physical as well as chemical adsorption.