CC BY
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Vafaev Oybek Shukurlaevich, Doctor of Philosophy (PhD), Senior Research Associate, LLC Tashkent Scientific Research Institute of Chemical Technology
E-mail: vafaev.oybek@mail.ru Tadjikhodzhaev Zokirkhodzha Abdusattorovich, Doctor of Technical Sciences, Professor, leading research associate, LLC Tashkent Scientific Research Institute of Chemical Technology
Djalilov Abdulahat Turapovich, Director, Academician of ANRUZ, Dr. Chem. Sciences, Professor, LLC Tashkent Scientific Research Institute of Chemical Technology
E-mail: a. t.djalilov@mail.ru
INFLUENCES OF DEPRESSOR ADDITIVE ON QUALITY INDICATORS OF DIESEL FUEL
Abstract. The possibility of decrease in temperature of hardening of diesel fuel by means of the depressor additives synthesized on the basis of secondary polymeric waste is shown in article. Depressor efficiency of additives depending on a ratio of their components is studied. It is shown that for decrease in temperature of freezing of diesel fuels by the most effective are introduction of depressor additives.
Keywords: depressor additiv, temperature of hardening, diesel fuel, efficiency of additives.
In the works on development of depressor ad- fuel hardening temperature on average on 12-180 °C
ditives, various by the nature, which are carried out depending on its hydrocarbonic structure.
by us earlier the factors influencing efficiency of Often diesel fuels differ on hydrocarbonic struc-
their action on low-temperature properties, such as ture, i.e. in different consignments of run diesel fuel
compatibility of a depressor with diesel fuel, size of paraffin of a normal structure (N paraffin), isoparaf-
its concentration, temperature of introduction of a fin, aromatics and others therefore the research of
depressor to fuel, presence of water and some other hydrocarbonic composition of fuels and his influ-
indicators have been investigated. ence on efficiency of the depressor additive DP3 is
From the depressors synthesized by us for fur- of a certain interest can prevail. For this purpose we
ther experiments the most effective additive DP3 into three samples of fuel in equal concentration en-
capable at concentration of 0.2% is defined to lower tered a depressor of DP3 (tab. 1).
Table 1.- Influence of concentration of a depressor on temperature hardenings of fuel, °C
Fuel Concentration of a depressor,%
0 0.05 0.1 0.2
sample 1 -14 -23 -25 -26
sample 2 -11 - -25 -27
sample 3 -7 -7 -9 -9
From (tab. 1) it is visible that efficiency of action of ous. It can be explained, from our point of view, with a depressor on temperature ofhardening of fuel is vari- various hydrocarbonic composition of fuel (tab. 2).
Table 2.- Hydrocarbonic structure of the studied samples diesel fuels,%
Group structure Diesel fuel
sample 1 sample 2 sample 3
N paraffin, from them 25 30 40
C -C C5 C14 12 15.5 19.5
C -C C15 C18 7 8 13
C -C C]Q C25 6 6.5 7.5
Isoparaffin 47 49 30
aromatic hydrocarbons, from them 10 10 8
monocyclic 5 5.8 5.8
Naftena 14 9.5 12
unsaturated hydrocarbons 4 1.5 10
Apparently from the (tab.) the 2nd samples of diesel fuels 1 and 2 considerably differ from a sample 3 on the group hydrocarbonic structure. The obtained data on dependence of efficiency of a depressor on hydrocarbonic composition of fuel well will be coordinated with references from which follows that generally hydrocarbons can be located in the following row on decrease of a susceptibility to depressors:
N paraffin & gt; aromatic hydrocarbons & gt; isoparaffin and naftena.
The good susceptibility of N paraffin to depressors is caused by the mechanism of effect of these additives which interact with the crystallizing paraffin. However N paraffin have high temperatures ofhardening, their presence sharply worsens low-temperature properties of fuels. At optimum concentration of N paraffin in fuel action of depressors is shown best of all.
Figure 1. Influence of concentration of additives on coefficient of filterability of diesel fuel
From aromatic hydrocarbons those which contain side paraffin chains are more susceptible. With increase in number of rings and reduction of length of side chains their susceptibility to depressors decreases [2].
From literature it is known that in some cases presence of depressor additives can negatively influence certain indicators of quality of fuel. So, at introduction of 0.2% of the additive VES-238 the coefficient of filterability of fuel of a summer grade increases to 30, then at a hrakneniye goes down a little, but all the same remains rather high concerning the normalized value equal 3, and sostavklyat 4-5. Increase in coefficient offilterability is observed also
Table 3.- Influence of a depressor
when using a depressor of Keroflux-5486. At test of the depressor of DP3 synthesized by us his insignificant influence, in comparison with the known analogs, on this indicator (fig. 1) is established.
Introduction of 0.2% of the additive VES-238 affects also increase in an indicator "the actual pitches" [3].
Tests by definition of influence of the developed additive DP3 on initial indicators of diesel fuel are carried out according to GOST 305-82 on a fuel sample 2 (tab. 3). At researches depressor additive with the concentration equal of 0.2% has been used.
on quality indicators diesel fuel
Normalized in Actual for fuel be- Actual for fuel
Name of an indicator accordance with fore introduction from 0.2% of a
GOST 305-82 of a depressor depressor
1 2 3 4
Cetane number, not less 45 47 47
Fractional structure:
50% are overtaken at a temperature, °C, not above 280 265 265
96% are overtaken at a temperature (the end of distillation), °C, not above 360 342 342
Kinematic viscosity at 20 °C, mm2/ with, (cSt) 3.0-6.0 4.2 4.2
The flash temperature for diesels of general purpose determined in the closed crucible, °C, not below 40 52 52
Mass fraction of sulfur,%, no more 0.20 0.17 0.17
Mass fraction of merkaptanovy sul-fur,%, no more 0.01 be absent
hydrogen sulfide content be absent
Test on a copper plate Stand
Content of water-soluble acids and be absent
alkalis
Concentration of the actual pitches, mg on 100 cm3 of fuel, no more 40 3 3
Acidity, mg the GAME on 100 cm3 of fuel, no more 5 1.26 1.26
Iodic number, of iodine on 100 g of fuel, no more 6 0.5 0.5
1 2 3 4
Ash-content,%, no more 0.01 be absent
Koksuyemost of the 10% rest,%, no more 0.20 0.028 0.028
Filterability coefficient, no more 3 1.5 1.5
Density at 20 °C, kg/m3, no more 860 810 810
From (tab. 3) it is visible that additive Dp3v introduction diesel fuel doesn't affect filterability coefficient, content of the actual pitches and other indicators.
Thus, the conducted researches have shown that efficiency of the additive DP3 considerably depends on hydrocarbonic composition of fuel and doesn't
worsen his quality indicators. Considering depressor efficiency and climatic conditions of the Republic of Uzbekistan, the developed additive, at rational selection of hydrocarbonic structure of a summer grade of diesel fuel, can be quite used for improvement of its low-temperature properties at operation of automotive vehicles during the winter period.
References:
1. Vafayev O. Sh., Tadzjikhodzjayev Z. A., Djalilov A. T. Republican scientific and practical conference "Urgent Problems of Chemical Science and Innovative Technologies of Her Training". 2016.- Tashkent.-P. 88-89.
2. Englin B. A. Use of motor fuels at low temperatures.- M.: Chemistry. 1980.- 208 p.
3. Danilov A. M. Use of additives in fuels.- M.: World. 2005.- 189 p.
