The inhibiting impact of three molecules of ethoxylated dodecyl alcohols (EDA) with different ethylene
oxide units against the corrosion of 316 stainless steel (316SS) in 2M HCl solutions was examined.
Electrochemical tests such as galvanostatic, potentiodynamic anodic polarization and electrochemical
impedance spectroscopy were applied to assign the electrochemical parameters. All the tests used
confirm the inhibitory action of EDA molecules. The inhibition efficacy increasing with increasing the
concentrations of EDA molecules, increase of ethylene oxide units and reducing at elevated temperature.
The inhibition was expounded by the forming of adsorbed film on the surface 316SS through the EO
unit while the hydrocarbon parts protrude brush –like into the solution. This adsorption obeyed Temkin's
isotherm. Galvanostatic polarization demonstrates that the EDA molecules act as mixed inhibitors. The
thermodynamic kinetics parameters for activation processes were determined and expounded. EDA
molecules reduces the pitting attack of 316SS in NaCl solution from the transmitting of the pitting
potential to the noble trend. |
