Inhibition study of mild steel corrosion in 1 M hydrochloric acid solution by 2-chloro 3-formyl quinoline

The corrosion inhibition study of 2-chloro 3-formyl quinoline was conducted for mild steel corrosion in 1 M hydrochloric acid solution at a temperature range of 303–333 K by chemical and electrochemical measurements. Inhibition efficiency increases with the increase of inhibitor concentration but decreases with increasing temperature. The polarization measurement reveals that the inhibitor acts as the mixed type and this inhibition effect is attributed to the adsorption of the inhibitor on the surface of mild steel from the bulk of the solution. The adsorption of 2-chloro 3-formyl quinoline on mild steel surface is exothermic and obeys the Freundlich adsorption isotherm. Thermodynamic parameters and activation parameters were calculated and discussed in depth. Scanning electron microscopy (SEM) micrographs were used to investigate the surface morphology of the steel sample in presence and absence of inhibitor.