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STUDY AND DEVELOPMENT OF TECHNOLOGY OF TRIBOLOGICAL
PROPERTIES OF DIESEL COMBUSTION
Karimova S.A.
sadoqat_karimova37@bsmi.uz
Abstract.
In this article, the results of studying C9-C17 carbon fatty acid amides as
lubricating-dispersing additives for diesel fuel are presented. Additionally, the determination
of lubricating-dispersing properties was carried out by sedimentation of the prepared
stabilizing agent system based on colloidal graphite of the C-1 grade at a concentration of
1.0% by mass, resulting in a change in optical density. The determination of antioxidant
efficiency was based on the photometric method, where, under experimental conditions, a
change in optical density in the oxidation process was detected.
Keywords:
diesel fuel, carbon fatty acid amides, lubricating-dispersing additives, optical
density, sedimentation, antioxidant efficiency, oxidation.
Аннотация.
В работе представлены результаты исследования амидов карбоновых
кислот С9-С17 в качестве моющие-диспергирующих присадок для дизельных топлив.
А также изучены моющие-диспергирующих свойств топлива на основе определения
изменения оптической плотности при седиментации модульных загрязнителей на базе
коллоидного графита марки С-1, взятого в концетрации 1,0 % масс. Определены
антиокислительной эффективности присадок к топливам и маслам, в основе которого
лежит измерение оптической плотности образца в ходе его окисления в заданных
условиях опыта.
Ключовые слова:
дизельные топлива, амидов карбоновых кислот, моющие-
диспергирующие присадки, оптической плотност, седиментация, антиокислительной
эффективность, окисления.
Аннотация
. Ушбу мақолада дизель ёқилғиси учун ювувчи – диспергирловчи
присадка сифатида С9-С17 карбон кислоталар амидларини ўрганиш натижалари
келтирилган. Шунингдек, ювиш-диспергирлаш хоссасини аниқлаш 1,0% масс
концентрациядаги
С-1
маркали
коллоид
графит
асосида
тайёрланган
ифлослантирувчи модул тизимни седиментацияланишида оптик зичликни ўзгариши
натижасида аниқланди. Антиоксидланиш самарадорлигини аниқлаш асосий усули
сифатида фотометрик усул танланди, у тажриба шароитида оксидланиш жараёнида
намуна оптик зичлигини ўзгаришига асосланган ҳолда топилди
Калит сўзлар:
дизель ёқилғиси, карбон кислоталар амидлари, ювувчи-
диспергирловчи присадкалар, оптик зичлик, седиментациялаш, антиоксидлаш
самарадорлиги, оксидланиш.
In our republic, diesel fuel is considered an important traditional fuel used in freight vehicles,
automobiles, and passenger buses, which are operated with diesel engines. According to
current forecasts, in the coming years (730.1 thousand tons in 2018, 701.2 thousand tons in
2019), the volume of diesel fuel consumption is expected to increase. Consequently,
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improving the quality and accelerating the combustion of diesel fuel and enhancing its
characteristics become significant issues.
The use of special additives is considered one of the directions for improving the quality of
diesel fuel [1, 86-97 p., 2; 64 p., 4; 228 p., 4; 250 p.]. Lubricating-dispersing additives are
widely used for extending the service life of diesel engines, ensuring the cleanliness of
engine parts, and fulfilling their function, which involves removing soot particles from the
"combustion" chamber.
In recent years, the use of composite additives containing cyclic amines and their derivatives
has been widely suggested as lubricating-dispersing additives for diesel fuel. Cyclic amines
and their derivatives have one important characteristic, thermal stability, which allows them
to be used in the composition of lubricating-dispersing additives for diesel fuel.
The following requirements are set for lubricating-dispersing additives: they should have
weak or low acidity, good solubility in diesel fuel, possess properties of surface-active
substances, and not decompose at temperatures of 220-250 °C. A "synergistic" lubricating-
dispersing additive is known to improve certain characteristics of engine and fuel system
lubricants at concentrations of 0.01-0.05% by mass. However, excessively high
concentrations may adversely affect fuel prices.
To produce multifunctional lubricating-dispersing additives that improve the operational
performance of diesel fuel, a variety of additives synthesized at low concentrations are
developed according to the purpose.
Multifunctional lubricating-dispersing additives synthesized based on higher fatty acids
(caprylic, lauric, myristic, palmitic, stearic), benzoic, m-toluic, nicotinic acids,
hydrazalondione-2,4, and morpholine, diethylamine, acrylamide were produced (3.1.). These
additives were tested on diesel fuel BNKI-2 (TDZ-1, TDZ-2, TDU) at a concentration of
0.0001% by mass.
The synthesized lubricating-dispersing additives include morpholine stearic acid (MSA),
morpholine benzoic acid (MBA), morpholine m-toluic acid (MTA), morpholine nicotinic
acid (MNA), diethylamine stearic acid (DEASA), and hydrazalondione-acrylamide (HAA).
The main physicochemical characteristics of HAA additive are as follows:
Appearance: yellow-brownish viscous liquid. Density, kg/m3 – not less than 920, 3. Amine
number, mg НС1 - not less than 33, 4. Solubility in diesel fuel - 50.0% mass fraction - clear
homogeneous liquid.
As for the standard additive composition: synergistic and LAG-01 lubricating-dispersing
additives, Agidol antioxidant additive were used. The additives were added to the diesel fuel
up to 0.001-0.5% mass concentration for DYO testing and up to 0.5% mass for I-20
industrial engine testing.
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Fractures, 2. Valve, 3. Gravity Source, 4. Light Receiver, 5. Main Channel, 6. Funnel, 7.
Sediment, 8. Start Channel, 9. Photometer, 10. Thermometer AZ8852, 11. Computer, 12.
Adapter.
The rapid laboratory method was used to evaluate the sedimentation of diesel fuel for
assessing its dispersing and antioxidant properties [1; 86-97 p.].
The rapid method for evaluating the sedimentation of the diesel fuel dispersing properties is
based on determining the change in optical density during sedimentation of the stabilizing
agent system prepared with 1.0% mass concentration of colloidal graphite of grade C-1.
The photosedimentometer consists of two layers, including a special burette. The upper layer
contains an standard suspension, while the lower layer contains the diesel fuel under
evaluation, in which the sedimentation of the fuel particles occurs. These layers produce
various sized particles, resulting in changes in optical density. These changes are detected by
a photodetector and converted into corresponding signals on the computer.
The region where the colloidal graphite particles of the diesel fuel dispersing properties are
stored is the sedimentation zone.The quantity and size of the particles were determined using
electron microscopy. The obtained results were further processed using computer software.
As seen in the second diagram, the hydrazalondione-acrylamide additive (HAA) increases
the settling time of the particles in suspension in the diesel fuel, prevents their coagulation,
and increases the optical density. The HAA additive (0.001-0.1)% mass concentration
significantly improved the dispersing properties of diesel fuel, especially at 0.1% mass
concentration where the optical density was equal to 375 mV. Below is the diagram showing
the effect of the concentration of the HAA additive on the dispersing properties of diesel
fuel:
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As shown in the diagram, the concentration of the HAA additive (% mass) has a significant
impact on the dispersing properties of diesel fuel. At concentrations of 0.001% and 0.01%,
the effect is considered nominal. However, at a concentration of 0.1% mass, the optical
density reaches 375 mV, indicating a substantial improvement in the dispersing properties.
Here's the requested diagram illustrating the evaluation of the antioxidant properties based
on the chosen method: The chosen method for evaluating the antioxidant properties is the
photometric method. It relies on changes in optical density during the oxidation process,
which serves as the basis for assessing the sample's antioxidant activity.
Image 3. Device for determining the thermal stability of diesel fuel samples (left - a steam or
water bath for heating samples, right - "Unifot" photometer for determining the optical
density of combustion).
To evaluate the thermal stability of the fuel, a specially designed cylindrical vessel with a
capacity of 3-5 ml was used, and the fuel was heated for 3-5 hours at temperatures up to
180°C. Oxidation was carried out simultaneously in 4 test tubes with 2 ml of sample each in
a thermostat-controlled water bath (see Image 3). The optical densities of the tested samples
were measured at wavelengths of 470 nm (blue filter) and 525 nm (green filter). The optical
density values at OD470 and OD525 were plotted against the oxidation time to create a
graph showing their dependence on the oxidation time [5,6].
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Image 1.
Dependence of the optical density at OD470 at 180°C on the oxidation time for
base diesel and diesel with 0.5% mass additives. 1 - Base diesel (BD); 2 - Biodiesel (BD); 3
- Synergistic; 4 - Diesel with additives.
The optical density at OD470 for the base diesel with additives is higher than that for the
base diesel alone, indicating that the thermal oxidation rate of the base diesel is highest,
resulting in more droplet formation during oxidation. The curve of the base diesel with the
MST additive lies below, suggesting that its oxidation tendency is lower, meaning that the
efficiency of the MST additive relative to synergistic and MBT additives is higher, i.e., its
inhibitory effect on oxidation is relatively stronger.
At the Bukhara Research Institute of Standardization, base diesel fuel with a concentration
of 0.2% mass additives LAG-03, synergistic, agidol, and HAA, was investigated for thermal
stability in the fifth figure at 180°C.
Emage 2
. (From Image 8) Effect of synergistic concentration on the oxidation of Bukhara
NQIZ diesel fuel at 160°C.
Image 9 depicts that at 160°C, the concentration of synergistic additive at both 0.1% and
0.2% mass significantly reduces the oxidation rate of Bukhara NQIZ diesel fuel, while at a
concentration of 0.001% mass, it accelerates oxidation. The synergistic additive
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demonstrates effective action at 180°C, where the oxidation of the base diesel fuel
accelerates sharply.
Image 3
shows the change in particle size after four hours of oxidation at 180°C for
diesel fuel. (a) represents fuel without additives (particle size 1.0-25.0 μm); (b) represents
fuel with a high-acidic additive (particle size 1.0-2.5 μm).
Microscopic examination results were obtained after diesel fuel samples in Figure 10 were
oxidized for four hours at 180°C. When diesel fuel without additives (Figure 12, a) was
oxidized, solid residue with particle sizes up to 25 μm was formed. When a high-acidic
additive (Figure 12, b) was added to the diesel fuel at a mass concentration of 0.001%, the
resulting particles had an average size of 2.5 μm.
Thus, when lubricating-dispersing additives based on carbon acids and amines (0.001-0.1%
by mass) were added to diesel fuel, the tribological properties of the fuel (lubrication,
dispersion, antioxidation) significantly improved.
LIST OF USED LITERATURE
1.
Spirkin V.G., Tatur I.R., Lazarev V.A., Shishkin Yu.L., Leontiev A.V. "Cleaning-
dispersing additive for diesel fuel." Proceedings of the Gubkin Russian State University of
Oil and Gas. 2014. No. 1(274). pp. 86-97.
2.
Mitusova T.N., Polina E.V., Kalinina M.V. "Modern diesel fuels and additives."
Moscow: Tekhnika, LLC "Tuma Group", 2002. 64 p.
3.
Danilov A.M. "Application of additives in fuels." Moscow: Mir, 2005. 288 p.
4.
Grishina I.N. "Physico-chemical principles and regularities of synthesis, production,
and application of additives improving the quality of diesel fuels." Moscow: Oil and Gas,
2007.
5.
Karimova S.A., Fozilov S.F., Mavlanov B.A., Fozilov Kh.S. "Methods for obtaining
lubricating-dispersing additives and their use in improving the characteristics of diesel fuel."
Journal "Advancement of Science and Technologies". 2023. No. 6. pp. 125-130.
6.
Karimova S.A., Mavlanov B.A., Fozilov S.F. "Synthesis of copolymers based on
quinazolinedione-2,4-methoxy-acrylate and acrylic monomers and their effect on the
physico-chemical properties of diesel fuel." Journal "Advancement of Science and
Technologies". 2022. No. 6. pp. 70-75.
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:7
,8
9
7.
Karimova S.A., Fozilov S.F., Mavlanov B.A. "Influence of lubricating-dispersing
additives on the characteristics of diesel fuels." Materials of the International Scientific and
Technical Conference "Actual Problems of Creating and Using High Technologies for
Processing Mineral and Raw Material Resources of Uzbekistan." Tashkent, November 16-
17, 2023. pp. 149-150.
8.
Karimova S.A., Fozilov S.F., Mavlanov B.A. "Synthesis of lubricating-dispersing
additives and their use in cleaning diesel engines." Proceedings of the International
Scientific and Practical Conference "Fundamental and Applied Issues of Physical and
Colloid Chemistry and Their Innovative Solutions." Namangan. 2024. pp. 160-163.
9.
Jumayev К., Zaripov G., Akhadova D., Amonova T., Khotamov К. Impact of
absorbents and changes of parameters of absorber operation on the level of absorption
drying of natural gas. VII international conference AGRITECH -2022. Advanced agrarian
technologies, Environmental Engineering and sustainable Development. Krasnoyarsk,
Russia, June 16-18, 2022.
10.
Jumayev К., Zaripov G., Akhadova D., Amonova T., Khotamov К. Impact of
absorbents and changes of parameters of absorber operation on the level of absorption
drying of natural gas. The Electrochemical Society. 243
rd
ECS Meeting SOFC- XVIII,
Boston, MA. May 28- June 2, 2023.
