Title : Evaluation of ecofriendly compounds performance as corrosion inhibitors for mild steel in molar hydrochloric acid: Electrochemical study and theoretical approach
Mild steel has been extensively used in several industrial processes due to its distinctive characteristics. However, it can unavoidably be corroded due to the harsh environment around it. Recently, the use of organic corrosion inhibitors is the most effective and economical approach of all anticorrosive methods. The corrosion inhibition performances of two ecofriendly compounds (amino acids) (P1) and (P2) for mild steel in 1.0 M HCl solution were investigated using potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) techniques. Data obtained from EIS studies were analyzed to fit inhibition process through appropriate equivalent circuit model. The results of the electrochemical methods showed that the studied molecules imparted high resistance and behaved as cathodic type inhibitors. The inhibition efficiency for the optimal concentration of 10-3M was 87% and 89% for P1 and P2 respectively. Both thermodynamic and kinetic parameters were calculated and discussed. The adsorption of the inhibiting molecules on mild steel surface was found to be chemisorption and followed the Langmuir isotherm. Surface analyses were also carried out by the mean of SEM-EDX and FTIR to confirm inhibiting process. The reactivity of P1 and P2 was quantum chemically analyzed by the DFT method to investigate the effectiveness of these water soluble Green inhibitors.
Keywords: Amino acids, HCl, Mild steel corrosion, Electrochemical techniques, SEM-EDX, FTIR, DFT.
Audience will understand new corrosion inhibiting mechanism using green compounds.
Audience (mainly industrials) could be interested in identifying and using new corrosion inhibitive molecules and appreciate the way they act in.
International exchange and future collaborations could be beneficial.