Electrochemical and thermodynamic evaluation on corrosion inhibition of C38 steel in 1 M HCl by Rumex ethanolic extract

Interdisciplinary research groups are interested in corrosion because it combines materials science, chemistry, physics, metallurgy, and chemical engineering. Corrosion is caused by the chemical and electrochemical action of an environment on metals and alloys. The consequences are severe in a variety of fields, particularly industry: production halts, replacement of corroded parts, accidents, and pollution risks are all common occurrences with potentially severe economic consequences. One of the most effective strategies for ensuring the protection of these metal materials in environments characterized by contact with aggressive acid media is the use of plant extracts as inhibitors. Rumex ethanolic extract is a novel green corrosion inhibitor for C38 steel in an acidic medium that is both inexpensive and environmentally friendly. Rumex extracted inhibitor (RNVLE) was used to overcome two major challenges for corrosion inhibitors: poor performance at high temperatures and low biodegradability. The extraction process by maceration produced a yield of 16%. Open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and polarization techniques were used to assess RNVLE' s inhibition performance. It was shown that the inhibition efficiency increased with increasing inhibitor concentration and decreased slightly with temperature increase. The RNVLE adsorption process on the C38 steel surface was found to be spontaneous and obeyed to Langmuir isotherm at all studied temperatures. The associated adsorption thermodynamic parameters led to suggest the occurrence of physical adsorption of the RNVLE compounds on the C38 steel surface.