Electrochemical Studies of the Inhibition Effectudof 2-Dimethylaminoethanol on the Corrosion of AusteniticudStainless Steel Type 304 in Dilute Hydrochloric Acid

摘要

The electrochemical behaviour of 2-dimethylaminoethanolud(DMA) on the corrosion of Type 304udaustenitic stainless steel in dilute hydrochloric solution wasudinvestigated through a weight-loss technique, open circuitudpotential measurement and potentiodynamic polarizationudtests at specific concentrations of DMA. Results show theudcompound to be highly effective with a maximum inhibitionudefficiency of 79 % from weight loss analyses andud80.9 % from polarization tests at 12.5 % DMA. The meanudcorrosion potential of −321 mV, obtained from open circuitudpotential measurement is within passivation potentials.udDMA inhibition protection was determined to occur throughuda physicochemical reaction mechanism on the steel surface,udconfirmed from calculated thermodynamic values.udDMA obeyed the Langmuir isotherm model. Data obtainedudfor inhibition efficiency from the three test techniquesudare in reasonably good agreement. The potentiodynamicudtest showed that the compounds acted as a cathodic typeudinhibitor.