Aqueous Extracts of Aaronsohnia Pubescens Subsp. Pubescens Aerial Parts As Green Corrosion Inhibitor for Mild Steel in Hydrochloric Acid Solution

In this study, the two aqueous extracts from the aerial parts of Aaronsohnia pubescens subsp. pubescens (Odorized aqueous extract (OE) and Deodorized aqueous extract (DE)) were used as some novel ecological corrosion inhibitors for mild steel (MS) in 1 M HCl medium. For this reason, the inhibition behavior of the OE and DE were having investigated using weight loss measurements, electrochemical assays, kinetic and thermodynamic parameters, electrochemical methods both stationary (Potentiodynamic polarization (PDP)) and transient (Electrochemical impedance spectroscopy (EIS)). The obtained results showed that EO and DE act as effective corrosion inhibitors and the inhibition efficiency of inhibitors increases for the concentration of 1.5 g/L; reaching some high values of 93.11 and 87.88 % in 1 M HCl solution at 308 K for OE and DE, respectively. Furthermore, PDP measurements exhibited that the studied of each inhibitor performs as a mixed-type inhibitor. The results of the thermodynamic kinetic parameters indicate the adsorption of OE and DE on the MS surface sites obeying the Langmuir adsorption isotherm.