STM Article Repository

Corrosion is one of the serious problems in industry, specially acidic corrosion which is caused by
acidic solutions which are widely used in acid cleaning, acid pickling and acid descaling. Mild steel
(MS) is widely used in the industrial field is vulnerable to be corroded by the acidic solution. In the
industrial media, corrosion processes are responsible for the loss of metals. There are various
methods to mitigation the degradation or destruction of metal surface. Using inhibitors is one of the
most potent methods in control of corrosion is due to its low cost and eases of application and
practice. Corrosion inhibition is favoured to prevent metal dissolution and acid consumption; which is
due to its low cost and simplicity of application. As the concern is focused on the safety of any
industrial process in health and environment, the use of organic plants as corrosion inhibitors is in the
forefront in the current trend of corrosion inhibition studies. In the last decades the need of novel
corrosion inhibitor compounds has become more and more stringent. Natural organic inhibitors could
be either synthesized or extracted from aromatic herb species or medicinal plants. In this study, the
efficiency of the bark of Olea europaea subsp. Cuspidata as corrosion inhibitor for mild steel in 1.0 M
sulphuric acid was studied by electrochemical measurements [potentiodynamic polarization (PDP)
and electrochemical impedance spectroscopy (EIS)]. The results showed that Olea europaea subsp.
Cuspidate wood tar oil acts as a potent corrosion inhibitor and the performance of the inhibitor varied
with concentrations for mild steel in 1.0 M H2SO4 + 10% EtOH. The maximum inhibition (%) was
94.97%, the results were supported by different techniques used. Electrochemical analysis indicated
that Olea europaea subsp. Cuspidata wood oil tar extract acts as mixed mainly cathodic inhibitor.
Also, surface analysis the scanning electron microscope (SEM) was carried out to determine the
corrosion inhibition property of Olea europaea subsp. Cuspidata wood tar oil in (1.0 M H2SO4 + 10%
EtOH) solution. The advantages of Olea europaea subsp. Cuspidata wood tar oil are several. The
adsorption of the wood tar extract on mild steel surface followed Langmuir isotherm.