A non-equilibrium approach to study the corrosion behavior of carbon steel in diethanolamine–H2O–CO2 systems

Abstract The present study aims at investigating the aggressiveness of the major CO 2 -containing species of diethanolamine (DEA)–H 2 O–CO 2 system, namely DEA carbamate and bicarbonate ions towards carbon steel via a non-equilibrium approach which allowed different ratios of carbamate to bicarbonate concentrations to be obtained. EIS and polarization tests were performed on AISI 1018 carbon steel specimens which had been exposed to the designed test systems. The results indicated that bicarbonate ion led to depassivation of steel while on the other hand no significant aggressive nature was detected for DEA carbamate ion.