Chemical Composition and Inhibition Effect of Eucalyptus Botryoides on the Corrosion of C38 Steel in Hydrochloric Acid Solution

In this paper research, the inhibition effect of Eucalyptus Botryoides essential oil (EO) on the corrosion of C38 steel in hydrochloric acid solution was investigated. Gravimetric method and electrochemical measurements, SEM morphology, and EDS analysis were used to verify this effect. The gravimetric results were showed that the concentration effect decreases the corrosion rate of C38 steel, which was confirmed by the electrochemical measurements. The potentiodynamic polarization results were exhibited that the EO inhibits the anodic and cathodic sites on the metal surface, and the EIS results were showed that the EO decreases the charge transfer at the interface metal/solution, without change the mechanism. The inhibition efficiency was found in order of 90 % at a maximum concentration of 2.4 g/L. SEM morphology and EDS analysis were proved the effective inhibition of EO by forming a protective film. The temperature effect was also realized, and the results show that the EO is also an effective inhibitor at high temperatures. These findings will have significant results in regard to industrial applications.