Synthesis and Inhibition of Imidazoline Derivatives as Corrosion Inhibitor

Corrosion inhibitors of imidazoline derivatives were synthesized using lauric acid, tetraethylenepentamine, and sebacic acid as raw materials. In simulated formation water environment saturated with CO₂, the inhibition performance of corrosion inhibitors on L360 steel was evaluated by weight loss mothed and electrochemical measurement. Scanning electron microscopy and energy spectrometer were used to analyze the corrosion products on the steel surface. The results show that the inhibition effect of four-ring lauric acid imidazoline inhibitor (LAI) was better than that of double-ring lauric acid imidazoline inhibitor (SAI), and the concentration of corrosion inhibitor that reached the highest corrosion inhibition rate was 400 mg/L. Both the two inhibitors followed Langmuir isothermal adsorption, which belonged to chemical adsorption. Combined with SEM and EDS analysis, it could be seen that SAI and LAI could form a layer of adsorption film on the surface of steel to inhibit metal corrosion.