Understanding Different Inhibition Actions of Surfactants for Mild Steel Corrosion in Acid Solution

摘要

The inhibition actions of different surfactants for corrosion of mild steel were studied byelectrochemical impedance spectroscopy and polarization measurements and weight loss. Cationicsurfactant: cetylpyridinium bromide (CPBr), non-ionic surfactant: triton (TX-100) and anionicsurfactant: dodecyl benzene sulphonate (DBS)in 1 M H2SO4.The order of the determined protectionefficiency was found to be CPBr > TX-100 > DBS, due to the differences in the molecular structuresof the three surfactants. The adsorption extent of CPBr was found to be higher than both TX-100 andDBS. A positive shift in the value of Epzc in presence of the CPBr was attributed to the specific+ adsorption of the halide ion Br- which facilitates the physical adsorption of the CP which iscommenced by chemisorption of the pyridinium ring via its -electrons with the surface Fe atom.Polarization curves and Weight loss measurements confirm the protection efficiency trends for thethree surfactants.