Influence of Polyethylene Glycols on the Corrosion Inhibition of Carbon Steel in Butyric Acid Solution: Weight Loss, EIS and Theoretical Studies

摘要

The effect of polyethylene glycols (PEG) of various average molecular weights (MW =1200, 4000 and6000) as inhibitors for the corrosion of carbon steel in 1.0 M butyric acid was investigated usingweight loss and electrochemical impedance spectroscopy (EIS) methods. Quantum chemicalparameters were calculated and discussed for theoretical study. The corrosion rate of carbon steel inbutyric acid decreased with increasing PEG concentration and molecular weight and increased withincreasing temperature. PEG inhibits the corrosion of carbon steel by an adsorption mechanism, whichfollows Temkin adsorption isotherm. Phenomenon of physical adsorption is proposed from the values0 of Ea and ads obtained.