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

3828 | P a g e A u g u s t 2 9 , 2 0 1 5 THE APPLICATION OF AMINO – AND HYDROXYETHYL IMIDAZOLINES OF PETROLEUM ACIDS AS MULTIFUNCTIONAL ADDITIVES FOR DIESEL FUEL Vagif Maharram Abbasov, Tarana Aslan Mammadova, Khayyam Rahim Valiyev, Anar Amil Namazov, Khayala Hamlet Kasamanli 1 Institute of Petrochemical Processes named after AcademicianYu.G.Mamedaliyev, Baku AZ1025,Azerbaijan 2 Ganja State University, Ganja AZ2000, Azerbaijan ABSTRACT In this research, the influence of aminoand hydroxyethylimidazolines 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 aminoethylimidazolines of petroleum acids on the antistatic property and lubricity of diesel fuel is better than the influence of hydroxyethylimidazolines, 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. Indexing terms/


INTRODUCTION
Nowadays there are miscellaneous complex procedures for obtaining environmentally friendly diesel fuels and the most widespread procedure is to decrease the compounds which contain sulfur, nitrogen and polycyclic aromatic hydrocarbons as a result of hydrogenation process of diesel fuels [1][2][3].
Despite this, reducing the amount of the heterocyclic compounds decreases the lubricity and antistatic effect of the fuel, therefore the details of the engine decay early and an instant spark causes ignition during the high-speed transference of fuel [4.5].
Nonetheless, it is clear that petroleum acids (PA) and their derivatives are applied to diesel fuel as additives for resource saving and improving some quality properties (lubrication, antistatic, anticorrosion and etc.) [11][12][13][14]. In this work, the influence of amino-and hydroxyethylimidazolines which were synthesized on the basis of natural PA fractions boiling in the range 140 -160ºC, 160 -180ºC and 180 -200ºC to the lubricity and antistatic property of diesel fuel is studied (Table 1).

Materials and methods
The petroleum acid fractions which were used for the research process have been obtained from HeydarAliyev Baku Oil Refinery of Azerbaijan; diethyltryamine (DETA) and N-Hydroxyethylendiamine (HEEDA) have been obtained from the "Sigma-Aldrich" company of Germany.
Imidazolines [17] were synthesized by the methods shown in the research. The influence of imidazolines on the lubricity of diesel fuel has been investigated in the HFRR apparatus according to CEC F-06-A-96 method. In the tests, the temperature was 60˚C and the volume of used fuel samples were 2 ml. The efficiency of the fuel lubricity was evaluated with photomicroscope by measurement of wear scar diameter (WSD) of balls.
The specific electrical conductivity (SEC) which characterizes the antistatic property of diesel fuel has been determined by the apparatus EL -4M according to GOST 25950.
The physical and chemical properties of diesel fuel which was used during the research are given in Table 2. As can be seen from Table 2, the diesel fuel does not meet the requirements for lubricity (WCD ≤ 460 µm) and for specific electrical conductivity (SEC ≥ 150 pS/m). For investigating the influence of imidazolines on the lubricity and antistatic property of diesel fuel, they have been added to diesel fuel at the interval of certain concentration. A u g u s t 2 9 , 2 0 1 5

The analysis of antistatic property
The influence of aminoethylimidazolines of PA on the antistatic property of diesel fuel is shown in Fig. 1. According to Fig. 1, it is revealed that, addition of aminoethylimidazolines of PA causes an increase in the antistatic property of diesel fuel. As can be seen from results, SEC was 81, 78 and 70 pS/m if the concentration of the aminoethylimidazolines of I, II and III fractions of PA was 50ppm, however, when the concentration was increased to 150ppm, SEC was also increased to 432, 413 and 370 pS/m respectively.
Besides, the value of SEC was changed between the interval of 171-184 pS/m of all fractions at the 75 ppm concentration of aminoethylimidazolines in the diesel fuel and it was above the minimum requirement (SEC > 150 pS/m) for antistatic effect. On the other hand, it was observed that, when the boiling point of imidazoline fractions increases, the antistatic effect decreases.
The influence of hydroxyethylimidazolines of PA on the diesel fuel is shown in Fig. 2.

Fig.2. The influence of hydroxyethylimidazolines of PA on antistatic property of diesel fuel.
The results (Fig. 2) illustrate that, like aminoethylimidazolines of PA, the influence of hydroxyethylimidazolines on SEC of diesel fuel is directly proportional to the concentration of them in diesel fuel. As can be seen from the curves, I fraction has the highest antistatic effect (394 pS/m), while III fraction of hydroxyethylimidazoline has the lowest antistatic effect (337 pS/m). Antistatic effect is decreasing from I fraction to III fraction of hydroxyethylimidazolines like aminoethylimidazolines. Furthermore, the results show that, the minimum concentration limit of I and II fractions was 75 ppm for meeting the requirements for antistatic effect of diesel fuel, however, this concentration limit for III fraction of hydroxyethylimidazolines was 100ppm.
During the researches, it was discovered that, the effect of imidazolines of PA on the antistatic property of diesel fuel is dependent on the storage life of diesel fuel as well. It was observed that, the antistatic effect of imidazoline containing diesel fuel increases over time. Taking into account of this, the SEC of amino-and hydroxyethylimidazolines of natural PA containing diesel fuels were measured at the first day of the addition of additive and after 30, 45, 60, 75 and 90 days. The results are shown in Table 3.

Table 2.The influence of storage life of diesel fuel on the SEC of amino-and hydroxyethylimidazolines of PA.
According to the researches, when 50 ppm aminoethyl and hydroxyethylimidazolines of PA are added to diesel fuel, it does not meet the requirements for the antistatic effect at the first day, however over time its antistatic effect increases. As can be seen from Table 3  HydroxyEIm A u g u s t 2 9 , 2 0 1 5

The analysis of lubricity
The influence of aminoethylimidazolines of PA on the lubricity of diesel fuel is illustrated in Fig. 3.

Fig.3.The influence of aminoethylimidazolines of different PA fractions on the lubrication quality of diesel fuel.
As can be seen from Fig. 3, while the concentration of imidazolines in diesel fuel increases, the lubricity of it increases as well. So, when the concentration of PA I frAminoEIm, PA II frAminoEIm and PA III frAminoEIm in the diesel fuel is 50 ppm, the WCD is 575, 584 and 589 µm respectively. When the concentration of imidazolines is increased to 250 ppm, WCD decreases to 436 µm for PA I frAminoEIm, 448 µm for PA II frAminoEIm and 460 for PA III frAminoEIm. As can be seen from the results, the value of WCD is below 460 µm when the concentration of PA I frAminoEIm is 200 ppm and the concentration of PA II frAminoEIm and PA III frAminoEIm is 250 ppm in diesel fuel.
In Fig. 4, the influence of hydroxyethylimidazolines of PA fractions on lubrication quality of diesel fuel is illustrated. As can be seen from Fig. 4, while the concentration of hydroxyethylimidazolines in diesel fuel increases, the lubrication quality of it increases like aminoethylimidazolines of natural PA.
So, when the concentration of PA I frHydroxyEIm, PA II frHydroxyEIm and PA III frHydroxyEIm in the diesel fuel is increased from 50 ppm to 300 ppm, WCD is decreased from 581 µm to 419 µm for PA I frHydroxyEIm, from 589 µm to 424 µm for PA II frHydroxyEIm and from 594 µm to 432µm for PA III frHydroxyEIm.
As can be seen from the results, the normal concentration is 200 ppm for PA I frHydroxyEIm, however, it is 250 ppm for PA II frHydroxyEIm and PA III frHydroxyEIm. Normal concentration of imidazoline is a concentration at which the lubricity meets the requirements. Besides, as can be seen from the graph, the maximum concentration limit, at which the imidazolines affect the lubricity of diesel fuel is 300 ppm. Above this concentration limit, a broad change is not observed in the lubrication property of diesel fuel.