GREEN INHIBITORS AQUEOUS EXTRACT OF Rumex vesicarius ON THE CORROSION OF CARBON STEEL IN ACID MEDIA 1M HCl

Green corrosion inhibitors are of interest because there has been an increase in environmental awareness and a change in regulations that restrict regular corrosion inhibitors due to their toxicity. Natural products are a good source of green corrosion inhibitors. In this study, the inhibition and adsorption properties of aqueous extract of flower from Rumex vesicarius (Rvaq) as corrosion inhibitors of XC70 carbon steel in 1M HCl were investigated using the gravimeter method and electrochemical techniques (potentiodynamic polarization and electrochemical impedance spectroscopy (EIS)) to monitor corrosion. The corrosion rate was found to decrease with increasing inhibitor concentration and the inhibition efficiency increases with increasing concentration of the (Rvaq) extract, with the maximum percentage corrosion inhibition efficiency more than 92% at 12.5%(v/v). There was also a positive correlation between temperature and corrosion rate; the thermodynamic results confirmed that the process of adsorption of the plant extract particles on the surface of the steel was of the physical type and endothermic; the adsorption mechanism between the extract and the carbon steel substrate is shown to obey the Langmuir and Temkin isotherms.