In this work, the effect of Henna extract as an inhibitor on the corrosion behavior of API 5L Gr.B steel in H2S-containing solution at 25 ˚C was investigated. The electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests were used for determination of corrosion parameters in the blank sample and samples with different concentrations of the extract. The obtained results indicated that with increasing Henna extract concentration, the corrosion current density decreased and the inhibition efficiency increased.
