Corrosion inhibition of carbon steel in cooling water systems by new organic polymers as green inhibitors

Abstract

Using the microwaves energy new organic polymers were synthesized by radicalic polymerization. These new organic compounds have anti-corrosive and anti-scale properties and for this reason, were used for cooling water systems protection. We presume that, these new organic polymers inhibit corrosion of carbon steel by a protective mechanism, forming insoluble iron complexes and repairing the porous oxide layers. The methods employed were potentiodynamic polarization, electrochemical impedance spectroscopy, and metallurgical microscopy techniques. The inhibition efficiency was high in all the studied cases. The corrosion parameters obtained from polarization curves and from EIS spectra are in good concordance and point out the inhibitory action of these new organic polymers. The adsorptions of the organic compounds on the carbon steels surface obeyed Langmuir's isotherm. Using FT-IR it was proved the adsorption of organic inhibitors and the formation of corrosion products on the carbon steels surface. The inhibition process was attributed to the formation of the adsorbed film on the metal surface that protects the metal against corrosive agents. The EIS measurements have confirmed this protection and pointed out the formation of adsorption layers on the electrode surface.