Adsorption and inhibition effect of 2,4-diamino-6-hydroxypyrimidine for mild steel corrosion in HCl medium: experimental and theoretical investigation

Abstract

2,4-Diamino-6-hydroxypyrimidine (2D6H) was examined as corrosion inhibitor of mild steel (MS) in 0.1M HCl using potentiodynamic measurements, linear polarization resistance (LPR), scanning electron microscopy, electrochemical experiments, and quantum chemical calculations. All measurements show that the corrosion inhibition effectiveness is forthright compared to the concentration of 2D6H ranging from 0.5 to 10.0mM. Adsorption of 2D6H on the MS surface in the presence of HCl is determined to obey Langmuir adsorption isotherm. The electronic features elucidated by quantum chemical calculations were associated with the experimental inhibition productivities. The mechanism of inhibition was revealed by E-pzc measurements.