Study on the Corrosion Inhibition Performance and Mechanism of N-Oleyl-1,3-Propanediamine on 20 Steel in HCl Environment

Abstract

In order to improve the protective performance of organic amine corrosion inhibitor on metals, an environment-friendly corrosion inhibitor FFA based on N-oleyl-1,3-propanediamine and diethylaminoethanol was developed. The corrosion inhibition effect of such FFA on 20 steel in 1 mol/L HCl was explored by static weight loss method. Moreover, the corrosion inhibition performance of FFA as well as the surface hydrophobicity, microstructure and roughness of 20 steel specimen took out from FFA in HCl solution were analyzed by static weight loss experiment, contact angle test, scanning electron microscopy(SEM), atomic force microscopy(AFM) and electrochemical workstation. Results showed that the corrosion inhibition efficiency reached the highest value of 94.5% when the FFA dosage was 5 g/L and the temperature was 343 K. The adsorption process of FFA on the surface of 20 steel was endothermic and conformed to the Langmuir isotherm model. Besides, a uniform hydrophobic film was formed on the surface of 20 steel after an immersion in FFA solution. FFA had excellent corrosion inhibition performance on 20 steel, and the inhibition mechanism was the combination of physical and chemical adsorptions.

Keywords

• fatty amine|corrosion inhibitor|adsorption|eis