Synthesis And Evaluation Of The Imidazoline Corrosion Inhibitior

Currently, a corrosion inhibitor, for its low cost, excellent effectand strong adaptability, was widely used to protect metal in oil, pickling,water treatment and other fields. As corrosion inhibitors, imidazolineand its derivatives is usually applied in the field of corrosion. The CO₂,corrosive gas and acid medium contained in oilfield mineralized water,result seriously in the corrosion of equipment wall. Therefore, it isessential that the inhibitors of friendly environment with goodperformance is continuously researched and developed in the presentbackground. This paper aims at synthesizing several corrosioninhibitors and investigating their corrosion performance.The present study prepared several the imidazoline inhibitorscontained fluorine. Firstly, the imidazoline intermediate was preparedemploying raw material acid （Oleic acid, lauric acid, palmitic acid, etc.）and diethylenetriamine, while its molecular size, interfacial tension andTGA was examined. Secondly, the fluorine inhibitor was fabricated withthe above intermediate and perfluoro-1-octanesulfonyl fluoride and itssynthesis process was optimized using productivity as test level. Whilethe optimal condition is identified as: perfluoro-1-octanesulfonylfluoride: triethylamine:imidazoline intermediate is0.5:1.2:1in molarratio, the reaction temperature is55℃and the reaction time isa rangeof4-5h. In addition, the inhibiting ability of the fluorine inhibitor wasinvestigated by weight-loss method, and compared with theintermediate.The inhibiting effects of oleic acid imidazoline and its derivativecontaining fluorine for Q235steel were investigated via weight loss method in acid solution and oil-water mixture. A quaternized oleicacid imidazoline was prepared with oleic acid imidazoline and benzylchloride. The partition coefficients of the three imidazoline inhibitorsbetween water and oil, were measured. The results show that, inhibitorconcentration, temperature and oil-water ratio have the positive effecton the mass transfer between two phases, while salt concentration has anegative effect. Finally, a gemini imidazoline inhibitor was synthesizedwith imidazolinone, diethylamine and epichloropropane, and its relatedperformance was examined.