The Inhibitive Effect of Vitamin-C on the Corrosive Performance of Steel in HCl Solutions - Part II
The inhibitive behaviour of Vitamin C, as a type of green inhibitor, on the corrosive behaviour of stainless-steel (SS) X4Cr13 within an aqueous solution of hydrochloric acid (HCl) was studied at concentration of c= (0.01, 0.1 and 1.0) mol L-1. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), was used for the measurements at 25 °C. To observe the morphology and microstructures of sample surfaces, after the electrochemical measurements a Scanning electron microscopy (SEM) was used. On the basis of the EDAX analysis within the solution of hydrochloric acid (0.01 mol L-1) with addition of Vitamin-C (0.005 mol L-1)the presence of the feri-chelates on the metal surface could be confirmed. The polarization curves revealed that the studied mixtures of the chosen inhibitor represented mixed-type of the inhibitor. The results show that the inhibition efficiency increases with the increase of the inhibitor concentration. This valid especially in the case of the lowest concentration of HCl (c=0.01 mol L-1). In addition to this at higher HCl concentration (c=1.0 mol L-1) the immersion time has a noticeable influence on the inhibitive response. Furthermore, the results obtained in this study showed that the inhibitory effect of Vitamin-C to a great extent on electrode potential.
green inhibitor, acid corrosion, steel, adsorption