RU2289612C1 - Fuel additive with low sulfur content for diesel engines - Google Patents

Abstract

FIELD: petroleum processing and petrochemistry.

SUBSTANCE: fuel additive for diesel engines containing sulfur in amounts below 500 ppm is a composition of tall oil and propylene pentamers at their weight ratio (3-9):1.

EFFECT: increased antiwear additive in diesel fuels.

2 cl, 5 tbl

Description

The invention relates to oil refining and petrochemistry, particularly to additives for fuels with sulfur content less than 500 million ^-1 for diesel engines.

Environmentally enhanced fuel with low sulfur content - at least 500 million ^-1 characterized by reduced antiwear properties, whereby life of the fuel injection equipment is reduced.

To provide the necessary level of antiwear properties, various types of antiwear additives are added to the fuel.

Known anti-wear additives for fuels containing naphthenic acids as active components (A.M. Danilov. Use of additives in fuels. M: Mir, 2005, 215 p.).

The disadvantage of these additives is the poor compatibility of the fuels containing them with engine oils and water. Such a requirement is mandatory for fuels for diesel engines.

Additives are also known, obtained on the basis of the interaction of mono- or polycarboxylic acids With ₂₄ -C ₆₅ and polyhydric (2-10) alcohols (Pat. Norway No. 169660, 1992), monoesters of dicarboxylic acids (AS USSR 458252, 04/15/1984 ), salts of an alkali or alkaline earth metal and polybasic acid (US Pat. US 4804389, 02/14/1989), esters of vegetable oils or the vegetable oils themselves (DE 4300207 A1, 01/07/1993).

Most of these additives show sufficient lubricity only in very high concentrations, so their use is economically disadvantageous.

The closest to the claimed additive in composition and purpose is an additive to fuel with low sulfur content for diesel engines, which is tall oil (RU 2165447 C2, 04/20/2001).

The disadvantage of this additive is its relatively low anti-wear efficiency, as a result of which its use is recommended in a relatively high concentration: more than 0.06% for fuel.

The present invention is the creation of additives with high anti-wear efficiency in diesel fuels.

To solve this problem, a real additive for low sulfur fuel for diesel engines containing tall oil and propylene pentamers in a mass ratio equal to (3-9): 1 has been proposed.

The additive further comprises a demulsifying additive in an amount of up to 1.0 wt.%.

The novelty of the proposed technical solution is the qualitative and quantitative composition of the additive, the components of which exhibit a synergistic effect. Previously, a similar additive in fuels was not used and was not offered. Its high anti-wear efficiency does not follow explicitly from known theoretical propositions.

In accordance with this invention, the inventive additive may further comprise at least one of the additives typically added to such fuels, for example detergent additives, cetane number improvers, anti-corrosion additives, additives that improve cooling resistance, and odor modifying additives.

The additive according to the invention is obtained by mixing calculated amounts of tall oil and propylene pentamers at 20-50 ° C.

To illustrate the proposed technical solution, additive samples were prepared by mixing the above components with the following characteristics:

Tall oil used the following grades:

1.1. Distilled tall oil, TU 13-00281074-26-95

Indicators Norm according to TU 13-00281074-26-95 Actually Appearance Light yellow to brown homogeneous liquid Acc. Density at 20 ° С, kg / m 850-900 875 Mass fraction of the main substance,% Not less than 95 97 Flash point, ° С Not lower than 200 207 Pour point, ° C - -7 Acid number, mg KOH / g Not lower than 140 164

1.2. Tall fatty acids, GOST 14845-79

Indicators Norm according to GOST 14845-79 Actually Acid number, mg KOH / g Not lower than 192 202 Flash point, ° С Not lower than 194 199 Mass fraction of resin acids,% No more than 2 1.4

Propylene pentamers produced according to TU 2411-020-05766801-94 of OAO Nizhnekamskneftekhim by propylene oligomerization have the following characteristics:

Name of indicator Norm according to TU2411-020-05766801-94 Fractional composition:
- boiling point, ° С, not lower
- end boiling point, ° С, not higher
170
300 Flash point in a closed crucible, ° С, not lower 70 Mass fraction of water,%, no more 0.1 Kinematic viscosity at 20 ° С, cSt, not more than 6.0 Pour point, ° C, not higher minus 60

To illustrate the invention, prepared samples of additives (table 1):

Table 1
Additive Composition Samples Component one 2 3 four 5 6 Tall fatty acids, wt.% one hundred 95 90 - - - Distilled tall oil, wt.% - - - 80 75 60 Pentamers of propylene, wt.% 0 5 10 twenty 25 40 Mass ratio of components: 19: 1 9: 1 4: 1 3: 1 1.5: 1

The effectiveness of additives was tested in diesel fuel containing from 0.005 to 0.05% of the proposed additive according to the method of American standard ASTM D 6079, included in TU 38.401-58-296-2001 "Diesel automotive fuel". According to this method, a steel ball under a load of 20 kPa (0.2 kg / cm) by means of a vibrator performs reciprocating movements with an amplitude of 1 mm and a frequency of 50 Hz along a plate placed in the test medium. Tests are carried out at temperatures of 60 and 25 ° C (it is taken into account that the fuel in the engine is in a heated state). The resulting wear spot is measured in two diameters (in the direction of travel and across) and the average is calculated. Then, the temperature and humidity are corrected, and the final result D obtained is a characteristic of this sample. The accuracy of the method at 60 ° C: repeatability - 80 microns, reproducibility - 130 microns; at 25 ° С: repeatability - 110 microns, reproducibility - 170 microns. The norm of antiwear properties of diesel fuel according to EN-590 and TU 38.401-58-296-2001 is D≤460 microns.

table 2
Diameter of wear spots during fuel tests with additive compositions An example of the table. one Concentration in fuel,% D, μm No additive - 562 1 (prototype) 0.01 512 2 0.01 490 3 0.01 411 four 0.01 358 5 0.01 322 6 0.01 460 1 (prototype) 0.005 515 four 0.005 405 1 (prototype) 0,025 480 four 0,025 315 1 (prototype) 0.05 452 four 0.05 345

Thus, a sufficient efficiency of the additive is manifested in the mass ratio of tall oil and propylene pentamers from 9: 1 to 3: 1. When these relations go beyond the boundaries, the anti-wear efficiency of the additive decreases to unacceptable values. The proposed additive is effective in fuel already at a concentration of 0.005 wt.%. With increasing concentration, its effectiveness increases, but this dependence is non-linear: with each portion of the additive, the increase in effect decreases.

Table 3 presents the physico-chemical and operational characteristics of the additive according to example 4.

Table 3 Indicators Actually The composition of the additive, wt.%: Distilled tall oil 80.0 Propylene Pentamers 20,0 Physico-chemical characteristics: Acid number, g KOH / g 111 Pour point, ° C -twenty Density, kg / m ³ 906 Operational properties of fuel with 0.01% additive: The diameter of the fuel wear spot, microns 358 Emulsifiability Does not form emulsions with water

An additive containing a demulsifying additive was prepared according to the invention.

Table 4 presents the composition of the obtained additives (examples 4, 7).

Table4 Additive Components Example 4 Example 7 Additive containing tall distilled oil - 80 wt.% + Propylene pentamers - 20 wt.%, Wt.% 100.0 99,2 Demulsifying additive - ethoxylated alcohol, wt.% - 0.8

Fuels containing special additives in contact with water may show a tendency to form stable emulsions. At low operating temperatures, these emulsions can complicate the operation of the engine or lead to its complete failure due to clogging of filters and nozzles, so it is important to prevent this phenomenon.

Assessment of the interaction of diesel fuel containing the antiwear additive according to example 4 and example 7 with water was carried out according to the method DGMK 531 (1B) - "Interaction with water (emulsifiability)".

This method allows one to evaluate the propensity of a fuel to form stable fuel-water emulsions.

The evaluation results are given in table.5.

Table 5 Rating Norm Diesel source Starting diesel fuel + additive according to example 4 Starting diesel fuel + additive according to example 7 Final grade (number of cycles / last cycle grade) No more than 5/2 5/2 5/2 5/1 Output compatible compatible compatible

As can be seen from table 5, both samples of diesel fuels (with the additive in example 4 and the additive in example 7) were tested for compatibility with water, however, the sample containing the additive in example 7 showed the best results.

Claims (2)

1. Additive to fuel with a low sulfur content for diesel engines containing tall oil, characterized in that it further comprises propylene pentamers in a weight ratio of tall oil: propylene pentamers equal to (3-9): 1. 2. The fuel additive according to claim 1, characterized in that it further comprises a demulsifying additive in an amount of up to 1.0 wt.%.