Corrosion Inhibition Behavior of Synthesized Imidazolium Ionic Liquids for Carbon Steel in Deep Oil Wells Formation Water

Abstract: 1-(2-Aminoethyl)-1-dodecyl-2-hexadecyl-4,5-dihydro-1H-imidazol-1-ium (PQI) and 1-(2-aminoethyl)-1-dodecyl-2-heptadecyl-4,5-dihydro-1H-imidazol-1-ium (SQI) are two ionic liquids compounds. FTIR, 1HNMR spectroscopic techniques were used to confirm PQI and SQI chemical structures. Quantum chemical calculations (QCC), potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) are various techniques which were utilized to evaluate PQI and SQI compounds as corrosion inhibitors for X-65 carbon steel in oil well formation water. The outcome experimental results showed that as the concentration of PQI and SQI compounds had increased, the inhibition efficiency increased gradually till reaching maximum value (94.68%) at 500 ppm of SQI compound. Surface morphology techniques (SEM, EDX) confirmed the formation of protective film on the carbon steel surface. PQI and SQI compounds were adsorbed on the carbon steel surface according to Langmuir adsorption isotherm model. Graphical Abstract: [Figure not available: see fulltext.]. © 2017, Springer International Publishing Switzerland.