Hydroxyethyl Imidazoline Research Articles

SYNTHESIS HYDROXYETHYL IMIDAZOLINES OF NATURE PETROLEUM ACIDS UNDER THE INFLUENCE OF CAVITATION EFFECT

The synthesis hydroxyethyl imidazolines of NPA under the influence of ultrasound took place under the influence of the cavitation effect created by ultrasound. It became clear from the results that by applying the cavitation effect of ultrasound to the classical method of synthesis of imidazolines, it is possible to reduce the synthesis time by 2–5 times compared to other synthesis methods, obtaining imidazolines with a yield of 92–97%. The synthesis time for this synthesis was 4 hours, the molar ratio of acid and amine was 1:1, the amplitude of the ultrasonic processor was 55% and the final temperature was 200oC

THE APPLICATION OF AMINO – AND HYDROXYETHYL IMIDAZOLINES OF PETROLEUM ACIDS AS MULTIFUNCTIONAL ADDITIVES FOR DIESEL FUEL

In this research, the influence of amino- and hydroxyethyl imidazolines of petroleum acids on the antistatic property and lubricity of diesel fuel has been studied. The researches illustrated that when the boiling point of petroleum acid fractions increases, the influence of imidazolines on the antistatic property and lubricity of diesel fuel decreases. Besides, it has been known that, the influence of aminoethyl imidazolines of petroleum acids on the antistatic property and lubricity of diesel fuel is better than the influence of hydroxyethyl imidazolines, On the other hand, it has been revealed that, when imidazolines of petroleum acids are added to the diesel fuel, the antistatic effect increases over time.

Corrosion Inhibition of 2-Undecyl-N-Carboxymethyl-N- Hydroxyethyl Imidazoline on Carbon Steel in Simulated Seawater Reverse Osmosis Product Water

Corrosion inhibition of 2-undecyl-N-carboxymethyl-N-hydroxyethyl imidazoline (UH- CI) on carbon steel in an artificial water, which simulated the water produced by seawater reverse osmosis (RO) process, was investigated by mass loss test, electrochemical methods, and X-ray pho- toelectron spectroscopy (XPS). Results show that UHCI could inhibit the corrosion of carbon steel, and the inhibition efficiency increases with the increasing concentration of UHCI. The UHCI acts as an anodic type inhibitor responsible for reducing the anodic current density. XPS results suggest that UHCI was adsorbed on the mild steel surface, which can effectively protect carbon steel from corrosion in the artificial water. Quantum chemical calculation results reveal that carboxymethyl and the ring of UHCI play the important role when UHCI adsorbed on carbon steel surface, which leads to the enhancement in the corrosion resistance of carbon steel and thereby a reduction in the

Synthesis, Corrosion Inhibition Performance and Biodegradability of Novel Alkyl Hydroxyethyl Imidazoline Salts

AbstractNew alkyl hydroxyethyl imidazoline salts were synthesized via a high pressure process with imidazoline and dimethyl carbonate, and their chemical structure were confirmed using mass spectral fragmentation and FTIR spectroscopic analysis. In addition, several quaternary ammonium salts with new counterions (formic acid, acetic acid and lactic acid) were also synthesized by ion exchange reaction of methyl carbonate quaternary ammoniums with the corresponding acids. These new compounds reduced the surface tension of water to a minimum value of approximately 27 mN m−1 at a concentration of 8.72 × 10−5 mol L−1. They also show efficient corrosion inhibition performances and could significantly inhibit the corrosion of mild steel in acid solutions. It was also found that the biological degradation of these imidazoline surfactants was greater than 98 % after 7 days.

The CO 2 corrosion inhibition of a high strength pipeline steel by hydroxyethyl imidazoline

The corrosion inhibition of a X-80 pipeline steel in saltwater saturated with CO 2 at 50 °C with hydroxyethyl imidazoline has been evaluated by using electrochemical techniques. Techniques included polarization curves, linear polarization curves, electrochemical impedance and electrochemical noise measurements with inhibitor concentrations of 0, 5, 10, 25, 50 and 100 ppm. Results showed that this inhibitor was an anodic-type inhibitor and the best inhibitor efficiency was reached with 25 ppm, and it increased as time elapsed. The corrosion process was different for inhibitor depending of its concentration; for doses lower than 25 ppm the process was under intermediate species adsorption control, whereas for 25 ppm of inhibitor concentration, the corrosion mechanism was under a mixed charge transfer and diffusion control. The monitoring of the film formation could be followed by using electrochemical noise measurements.

A study of hydroxyethyl imidazoline as H2S corrosion inhibitor using electrochemical noise and electrochemical impedance spectroscopy

A study of H2S corrosion inhibition of pipeline steel by hydroxyethyl imidazoline has been carried out by using electrochemical techniques. Inhibitor concentration included 5, 10, 25, 50, and 100 ppm in a H2S-containing 3% NaCl solution at 50 °C. Techniques included linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS), and electrochemical noise (EN) measurements. In addition to the traditional noise in voltage and current, noise resistance (R n) measurements were used. All techniques showed that the most efficient inhibitor concentration was between 5 and 10 ppm, but inhibitor efficiency decreased after 8 h of testing. Furthermore, EN measurements showed that steel was highly susceptible to localized corrosion at inhibitor doses lower than 10 ppm due to the establishment of a porous inhibitor film. However, with 50 or 100 ppm of inhibitor, the steel was susceptible to a mixture of uniform and localized corrosion. Hurst exponent was higher in presence of inhibitor for times shorter than 8 h, indicating a short residence time of the inhibitor. The data could not be fitted to any adsorption isotherm model, indicating a lack of strong adsorption of the inhibitor to the metal surface.

Carbon dioxide corrosion inhibition of N80 carbon steel in single liquid phase and liquid/particle two‐phase flow by hydroxyethyl imidazoline derivatives

AbstractCO2 corrosion inhibition of N80 steel in liquid single‐phase and liquid/particle two‐phase flow by 2‐undecyl‐1‐hydroxyethyl imidazoline (HEI‐11) and 2‐undecyl‐1‐hydroxyethyl‐1‐hydroxyethyl quaternary imidazoline (HQI‐11) was investigated using weight loss, potentiodynamic polarization, EIS, and scanning electron microscope (SEM) techniques. The results show that the corrosion rate in the absence and presence of the imidazolines is strongly dependent on the flow condition and presence of entrained sand particles. The imidazolines function via a mixed‐type corrosion inhibition mechanism. The inhibition efficiencies of the imidazolines followed the trend HQI‐11 > HEI‐11 in all the systems studied. Inhibition mechanism has been discussed in relation to the polycentric adsorption sites on the imidazoline molecules.

Inhibition Behavior of Two Imidazoline-Based Inhibitors with Different Hydrophilic Groups in Single Liquid Phase and Liquid/Particle Two-Phase Flow

Two kinds of imidazoline inhibitors with different hydrophilic groups, i.e. hydroxyethyl imidazoline (HEI-11) and aminoethyl imidazoline (AEI-11), were used for resisting CO, corrosion of N80 steel in single liquid phase and liquid/particle two-phase flow. Inhibition performance of these imidazoline inhibitors for CO, corrosion of N80 in 3% (omega) NaCl solution was investigated using polarization curve and electrochemical impedance spectroscopy under static and flow conditions. The results showed that the inhibition efficiency under both static and flow conditions increased according to the following: HEI-11>AEI-11. The inhibition performance of both inhibitors was severely degraded by single liquid phase and liquid/particle two-phase flow at 5 m . s(-1). Additionally, quantum chemical calculation was carried out to correlate the inhibition performance of both inhibitors with their chemical structures and to explain the inhibition mechanism. The theoretical calculation was in good agreement with experimental results.

Effect of hydrophilic group on inhibition behaviour of imidazoline for CO2 corrosion of N80 in 3%NaCl solution

Four kinds of imidazoline inhibitors with different hydrophilic group, i.e. carboxymertyl imidazoline (CMI-11), hydroxyethyl imidazoline (HEI-11), aminoethyl imidazoline (AEI-11) and imidazoline (IM-11) had been synthesised and characterised by infrared and ultraviolet spectra. The inhibition performance of these imidazoline inhibitors for CO2 corrosion of N80 in 3%NaCl solution was investigated through linear polarisation resistance, polarisation curve and electrochemical impedance spectroscopy. In order to study the relationship between the molecular structure and inhibition properties of these imidazoline inhibitors, quantum chemical calculations have been also applied. The results showed that the presence of a hydrophilic group was beneficial to the corrosion inhibition properties of these imidazoline inhibitors, and the inhibition efficiency follows the order: CMI-11>HEI-11>AEI-11>IM-11. The calculated quantum chemical parameters supported that the lower the lowest unoccupied and highest occupied molecular orbital energy gap, the higher the inhibition efficiency. The theoretical calculation was in good agreement with experimental results.

Effect of chemical structure of hydroxyethyl imidazolines inhibitors on the CO2 corrosion in water–oil mixtures

The corrosion inhibition of oleic, coconut, and stearic acid modified hydroxyethyl imidazolines on 1018 carbon steel was evaluated by using potenthiodynamic polarization curves, linear polarization resistance, and electrochemical impedance spectroscopy techniques. Solutions included deaerated CO2 saturated 3% NaCl with and without Diesel at 50 °C. Regardless of the presence of diesel, the corrosion rate was decreased with the addition of the inhibitors, but the time to reach a steady state was longer than when the oily part, i.e., diesel, was present. This was because the inhibitors are oil soluble, and with diesel, they are more easily transported towards the metal surface. With diesel, the formed film seems to be more stable and protective, not allowing the electrolyte to corrode the sample increasing the efficiency values up to 87 and 94%. The most efficient inhibitors were the coconut type fatty acid hidroxyethyl imidazoline because the formed film was much more stable from the beginning of the test, whereas the least efficient was the stearic acid modified hydroxyethyl imidazoline.

CO2 corrosion inhibition by hydroxyethyl, aminoethyl, and amidoethyl imidazolines in water–oil mixtures

The corrosion behavior of hydroxyethyl, amino ethyl and amid ethyl imidazolines corrosion inhibitors was evaluated by using potenthiodynamic polarization curves, linear polarization resistance, and electrochemical impedance spectroscopy techniques. Solutions included deaerated 3% NaCl, 3% NaCl+diesel saturated with CO2 at 50 °C with and without inhibitors. Regardless of the presence of diesel, the corrosion rate was decreased with the addition of the inhibitors, but the time to reach a steady state was longer than when the oily part, i.e., diesel, was present. In the absence of the oily part, the impedance results showed that the film formed was porous, allowing the electrolyte to diffuse through it and corrode the metal. When the oily part was present, the film formed was much more stable, not porous, and did not allow the electrolyte to corrode the sample. The most efficient inhibitor was the amid ethyl imidazoline, whereas the least efficient was the hydroxyethyl imidazoline, because the film formed by the former was much more stable from the beginning of the test.

Computational simulations of the molecular structure and corrosion properties of amidoethyl, aminoethyl and hydroxyethyl imidazolines inhibitors

To proof the corrosion efficiency of hydroxyethyl, aminoethyl and amidoethyl imidazolines, they were evaluated by linear polarization resistance and polarization curves in deaerated 3% NaCl + Diesel + inhibitors saturated with CO 2 at 50 °C. The most efficient inhibitor was the amido ethyl imidazoline, with an efficiency of 97.88% whereas the least efficient was the hydroxyethyl imidazoline, with an efficiency of 88.8%. A theoretical study of the corrosion inhibition efficiency of these imidazoline derivatives, was carried out using density functional theory (DFT). The computational calculations were used to obtain information about their molecular structure and those properties related with the inhibition efficiency of these inhibitors. The obtained correlations and theoretical conclusions agree well with the experimental results.