Inhibitive effect of some phosphonate derivatives on the corrosion of carbon steel in 2 M H3PO4

Abstract

Corrosion inhibition performance of some phosphonate derivatives, namely, dodecylphosphonic

acid (YM1),  sodium methyl dodecylphosphonate (YM2) and methyl hydrogen dodecylphosphonate (YM3)  on carbon steel in 2 M H₃PO₄ solution was investigated by means of weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. These compounds inhibit the corrosion rate even at very low concentrations and the order of increasing inhibition efficiency was correlated with the modification of the molecular structure of the inhibitors. Polarization curves indicated that these compounds acted primarily as mixed-type inhibitors. The adsorption of these compounds on carbon steel surface has been found to obey Langmuir’s adsorption isotherm. E% values obtained from weight-loss and electrochemical methods were in good agreement.

size:12.0pt;line-height:200%;font-family:"Times New Roman","serif"; color:black'>.