Improved Pitting Corrosion Resistance of Stainless Steel 304 by Lupine extract in Hydrochloric Acid

Improving pitting corrosion resistance of stainless steel 304 by Lupine investigated in 0.5 M HCl solution using Weight loss measurements, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The polarization results showed that Lupine extract act as anodic -type inhibitor with a high protection efficiency of 92% at extract addition of 15 ppm. EIS measurements showed that the dissolution process of stainless steel occurs under diffusion control. The adsorption behavior of the main Lupine extract constituents on stainless steel surface was well described following Flory-Huggins isotherm and Kinetic-Thermodynamic model. Surface studies using SEM-EDX techniques supported the obtained chemical and electrochemical results.

Automated summary

In this study, the improvement of pitting corrosion resistance of stainless steel 304 by Lupine in HCl solution was investigated. Various techniques including weight loss measurements, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization were used. The results showed that Lupine extract can act as an anodic inhibitor with a high protection efficiency. Surface studies using SEM-EDX techniques supported the obtained results.