Method For Preparing Imidazoline Corrosion Inhibitors From Food Waste Oil And Evaluation Of Its Properties

Hydrochloric acid and soil acid has been used in acid fracturing process widely, but this kind of acid fluid in a certain environment that will cause the metal materials corrosion of the shaft and the ground pipe. With the development of oil and gas exploitation and transportation technology, the corrosion protection workers are committed to research and use many kinds of protection methods to slow down the corrosion of metals, and the use of corrosion inhibitors is an effective method. As a kind of inhibitor, Imidazoline Corrosion inhibitor molecules containing some polar groups, which easy to be adsorbed on the metal surface, and has a good corrosion inhibition performance on carbon steel of oil and gas conveying pipe.Swill-cooked dirty oil, commonly known as waste oil, refers to the presence in the life of all kinds of low-quality oil, such as recycled cooking oil, the repeated use of frying oil, etc. It's largest source is oil separating tank of large hotel in the city. The long-term consumption of such oil may lead to a series of serious illnesses such as cancer, and cause great harm to people's health. As a serious threat to the environment, swill-cooked dirty oil, but contains a lot of good fatty acids, can synthesis a kind of imidazoline inhibitor. In this paper, will-cooked dirty oil as raw materials, through pretreatment and quaternary amine reaction formula modulation process, synthesized the imidazoline corrosion inhibitor successfully. The product was characterized by infrared spectrometer, results show that was imidazoline products. Analysis of physical, chemical and toxicological studies have shown that the imidazoline inhibitor was a stable and green environmental protection product, complianced with relevant standards.The corrosion inhibition performance of the corrosion inhibitor on L360 steel was evaluated by static and dynamic weight loss method, filming test and electrochemical method. The results shown that the corrosion inhibitor for cationic type corrosion inhibitor, corrosion inhibition efficiency increased with the increase of the inhibitor concentration gradually, when the concentration reached 500 mg/L in hydrochloric acid system of L360 pipe steel corrosion inhibition efficiency reached 87.97%. The surface morphology of L360 steel was observed by the SEM, and the obtained results were further verified from the microscopic view. To explore the inhibition mechanism of imidazoline inhibitor by using the adsorption model,and found the adsorption happended on the surface of L360 steel follow the Langmuir adsorption isotherm, and through the calculation of the system in the metal anode dissolution, corrosion inhibitor in this paper is a chemical adsorption.The application effect of the corrosion inhibitor was evaluated in the oilfield and the results show that the corrosion inhibition efficiency of corrosion inhibitor in the selected oil well high to 90.2%, which meets the requirements of the field to the corrosion inhibitor.