Liquid chromatography/electrospray ionisation mass spectrometric investigations of imidazoline corrosion inhibitors in crude oils

Abstract

The so-called imidazolines (2-alkyl-1-[ethylalkylamide]-2-imidazolines and 2-alkyl-1-ethylamine-2-imidazolines) are a group of surface-active compounds, complex mixtures of which are used by various industries as surfactants and corrosion inhibitors. Although their industrial synthesis was reported over 100 years ago, few methods for the determination of individual imidazolines in mixtures, including industrial matrices such as crude oils, have been reported. Here we demonstrate that spiking of crude oils with synthetic imidazolines followed by solid-phase extraction and liquid chromatography/electrospray ionisation multistage mass spectrometry (LC/ESI - MS(n)) allows an estimation of low (<10) parts per million concentrations of individual imidazolines in crude oils. Whilst non-optimised at present, the method is a significant advance and may prove useful not only for improving an understanding of the mechanisms of industrial imidazoline synthesis and for monitoring downhole and topside oilfield operations, but also for the determination of the fate of imidazoline-based oilfield corrosion inhibitors and surfactants in the environment.

Engineering Surface Functional Groups on Silica Aerogel for Enhanced Cleanup of Organics from Produced Water

“…Fatty acids that have been reported in produced water range from C 1 to C 9 , and reported concentrations are also shown in Table 1. Although there are methods for measuring production additives, [8][9][10][11] little data is available about specific compounds and concentrations of corrosion and scale inhibitors, demulsifiers and defoamers, and biocides in produced water. Thus, engineering treatment methods to remove these components can only be done in collaboration with industrial partners.…”

Physicochemical Study of some Imidazoline Derivatives in Solutions

“…Using these equations, the (MRD) 2 and refractive index of compounds in 0.1 M solutions were calculated and are given in Table 3. It is observed that both (MRD) 2 and refractive index of compounds are different in each solvent. This again proves that in different solvents, intermolecular interactions are different which affects these parameters.…”

“…The synthesis of imidazoline derivatives continues to attract much interest in organic chemistry due to its various therapeutic properties [1][2][3][4][5][6][7][8]. This class of compounds is known to have applications in various fields [9,10].…”

Development of UV/VIS spectrometric methodology for corrosion inhibitor residuals monitoring in oilfield brine

“…In CE, amines are generally separated as cationic species, and detected indirectly using low-pH electrolyte systems containing UV-absorbing additives [29 -34]. Sophisticated techniques, such as liquid chromatography/electrospray ionisation multistage mass spectrometry [35] and particle induced X-Ray emission spectroscopy [36], were applied as well. Different components of the corrosion inhibitor can be analytically determined; ester peak was used to quantify the concentration of the residual inhibitor in inhibitor/diesel solution by using carbon-13 NMR and Fourier Transform infrared spectroscopy [37].…”