Carbon steel is the principal material used in oil and gas production pipelines. However, carbon steel is vulnerable to corrosion by corrosive media it contacts, and this causes economic losses. The corrosion rate of carbon steel is inhibited by imidazoline, an organic corrosion inhibitor. In this study, oleic-imidazoline was successfully synthesized from triethylenetetramine and oleic acid under reflux at 100–140°C for 12 h. The synthesized compound was characterized for its structure by using FTIR, UV-Vis, NMR (1H and13 C), and LC-MS/MS spectral data. Oleic-imidazoline showed a maximum absorption peak at a wavelength of 203.8 nm (UV-Vis), absorption peaks at 1656.51 cm–1 belonging to C=N bond (FTIR), a peak at a chemical shift of 2.17 and 3.30–3.48 ppm indicating H–C–C=N and imidazoline ring proton, respectively (1 H NMR), and a peak at the chemical shift of 164.6 ppm fitting C=N (13 C NMR). LC-MS/MS showed that oleic-imidazoline was a major component in the synthesized compound with [M+H]+ 393.37 m/z at rt 10.87 min. The oleic-imidazoline’s performance as a corrosion inhibitor toward low carbon steel in a 1% NaCl solution was measured using two methods, which are Tafel polarization and weight loss. The highest inhibition efficiency percentage (%IE) resulted from the two methods are 83.26% and 83.33%, respectively. Oleic-imidazoline reveals good performance to inhibit the corrosion since this compound undergoes physisorption with slight chemisorption on low carbon steel in chloride environment.
|Number of pages||12|
|Journal||International Journal of Corrosion and Scale Inhibition|
|Publication status||Published - 2021|
- Chloride environment
- Corrosion inhibitor
- Low carbon steel