Inhibition of Carbon Dioxide Corrosion of Mild Steel by Imidazolines and Their Precursors

Abstract

Corrosion inhibition of mild steel by imidazolines and their precursors in a carbon dioxide (CO 2 )-containing environment was studied using rotating cylinder electrode (RCE) and linear polarization resistance (LPR) techniques. Corrosion rate-time/concentration profiles and minimum effective concentrations obtained for a series of imidazolines and amides were evaluated in terms of the respective contributions of their constituent parts (imidazoline ring, amide/amine group, and hydrocarbon chain) to overall corrosion inhibition. Formation of the inhibitor film was studied in terms of the bilayer/multilayer film model. FIGURE 9. Corrosion rate/potential-inhibitor concentration dependence for stearic amide/imidazoline constant concentration treatments.FIGURE 10. Corrosion rate/potential-time response for lauric imidazoline constant concentration treatment at 0 rpm and 6,000 rpm.

Effectiveness of Imidazoline in Mitigating Transport Pipeline Corrosion

“…These include the pedant chain structure, alkyl chain length and tilt, solubility, concentration, permeability, presence of impurities, natural gas velocity and operating temperature [11,[13][14][15][16]. Tan et al [13] provided an hypothesis that imidazoline compounds did not adhere to established adsorption models; this was however disproved by Mazumber et al [11] using the Langmuir isotherm adsorption mechanism under certain conditions.…”

“…Further, the attachment of a polar group to the pendant chain will increase the hydrophilic nature due to the polar nature of water [20]. Jovancicevic et al [14] concluded that at a critical micelles concentration (CMC), imidazoline is highly dispersible. This suggests the imidazoline will be rapidly transported to the metal surface where they will form a stable boundary layer; however, concentrations higher than the CMC will be superfluous.…”

“…Jovancicevic et al [14] suggests in his research that Imidazoline molecules will also hydrolyse and form their amide precursor under high temperature conditions. The Imidazoline ring is also thought to become increasingly unstable with a temperature rise [28].…”

A Review of CO2Corrosion Inhibition by Imidazoline-based Inhibitor

“…The pronounced effect of the hydrocarbon chain R1 is the formation of protective film at the [14] stated that the length of R1 in the range of C12 to C20 has significant importance in the corrosion inhibition of IMs. In addition, no evident inhibition was observed with the application of C8 imidazoline.…”

Imidazoline Corrosion Inhibitor in Metal Acid-Phase Reactors in Anaerobic Digestion

“…Therefore, many research works has been focus on the formation of inhibition film on the metal surface to protect it from corrosion [9]. The inhibition efficiency of organic compounds has relevance with their adsorption properties to the metal surface, which includes many factors, such as metal surface property, active group chemical structure of inhibitor [10]. Many imidazoline derivatives have been used as metal corrosion inhibitors and especially primarily applied in the petrochemical plants and wells and corrosion mechanism of it was also widely research and analysis recently to know how it works [11,12].…”