INHIBITION OF CARBON DIOXIDE CORROSION OF MILD STEEL VIA BIS-IMIDAZOLINE COMPOUNDS

Bis-imidazoline ammonium salt was synthesized via oleic acid with polyethylenepolyamine followed by the interaction of acetic acid at molar ratio 1:1. Anti-corrosion effect of obtained complex salt was studied on the mild steel of C1018 mark in the saline solution, saturated by CO2. It was found that ammonium salt of imidazoline inhibits carbon dioxide corrosion of mild steel of C1018 mark effectively. The test inhibitor relates to corrosion inhibitors of mixed action, i.e. decreases the speed of both cathodic and anodic reactions. The adsorption of the bis-imidazoline compound on the mild steel surface obeys the isothermal Langmuir equation and refers to chemical adsorption. Scanning electron microscopy (SEM) analyzes the state of the corroded surface of protected electrodes made of C1018 steel. The mechanism for inhibition is suggested on the basis of all these results