Abstract:

In this paper, the corrosion inhibition performance of a newly synthesized oleic acid imidazoline amide (EYP) which was intended to be used in the overhead circulating reflux system of fractionating tower was investigated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests. The surface morphologies of mild steel specimens were observed by scanning electron microscope (SEM) and the kinetic parameters were calculated from experimental weight loss results. Weight loss and SEM results demonstrated that EYP can effectively protect A3 mild steel from corrosion in simulative top cycle oil. The inhibition efficiency of EYP increased firstly and then decreased mildly with the increase of EYP concentration and the inhibition efficiency decreased mildly as the experimental temperature increased. Electrochemistry results showed that EYP was a mixed-type inhibitor retarding mild steel corrosion without changing the mechanism of anodic or cathodic reaction. The calculated kinetic parameters revealed that EYP was absorbed onto mild steel by both chemisorption and physisorption.

Key words: oleic acid imidazoline amide, corrosion inhibition property, A3 mild steel, fractionation tower, overhead circulating reflux system