Ali Yousefi - Department of Chemistry, Faculty of Science, Tabiat Modares University, Tehran, Iran
Soheila Javadian - Department of Chemistry, Faculty of Science, Tabiat Modares University, Tehran, Iran

The corrosion inhibition of sodium dodecyl sulfate (SDS) on stainless steel has been investigated in hydrochloric acid at different temperatures at different concentrations of the inhibitor using mass loss, potentiodynamic polarization and electrochemical spectroscopy measurements. A significant decrease in the corrosion rate was observed in presence of the investigated inhibitor. The galvanostatic polarization curves showed that, the inhibitor behaves as mixed type but the cathodic effect is more pronounced. The surface tension at 298K was measured, the critical micelle concentration (cmc) and some surface active parameter were calculated. The inhibition efficiency (η%) of this surfactant has been studied by both chemical and electrochemical techniques at 25˚C. The observed corrosion data indicate that, the inhibition of mild steel corrosion is due to the adsorption of the inhibitor molecules on the surface. The adsorption mechanism onto steel surface in acid medium in the absence and presence of surfactant was also discussed.

Anionic surfactant, Corrosion, Hydrochloric acid, Inhibitor