COMPOSITION OF ADDITIVES AND HIGH-PERFORMANCE FUEL
COMPRISING SUCH A COMPOSITION
5 PRIOR ART
The present invention relates to compositions of additives and fuels containing
such compositions of additives. The present invention relates in particular to
compositions of additives for diesel and/or bio diesel fuel. The present invention
10 further relates to the use of such fuels in diesel engines to improve their
performance, in particular in diesel engines with a fuel injection system of type
Euro 3 to Euro 6.
Fuels that are marketed must comply with national or supranational specifications
15 (for example standard EN 590 for diesel fuels in the EU). For commercial fuels,
there is no legal obligation concerning the incorporation of additives. From the
commercial point of view, in the area of fuel distribution, a distinction is made
between "base price" fuels, with few or no additives, and higher-grade fuels in
which one or more additives are incorporated to improve their performance
20 (beyond the regulatory performance).
In many countries the sulphur content of diesel fuels has been subject to a very
significant reduction for environmental reasons, in particular in order to reduce SO2
emissions. For example, in Europe, the maximum sulphur content of fuels of the
25 diesel type for road vehicles is currently 10 ppm by mass. To compensate for the
loss of compounds providing the lubricating character of these fuels, numerous
lubricity and/or anti-wear and/or friction-modifying additives have been introduced
into the fuels That are marketed.
30 Their characteristics are broadly described in patents EP915944, EP839174 and
EP680506.
2
DRAWINGS
- Figure 1 is a photograph of a high-pressure, direct-injection diesel engine
injector
5 - Figure 2 is a photograph of a needle of a direct-injection diesel engine
injector, fouled with deposits of the soap and/or lacquer type ("lacquering")
- Figure 3 is a photograph of a nozzle of an indirect-injection diesel engine
injector, fouled with deposits of the coke type ("coking")
- Figure 4 is a photograph of a needle of a direct-injection diesel engine
10 injector, fouled with deposits of the soap and/or lacquer type ("lacquering")
As shown in Figures 1 and 2, it was found that when using certain higher-grade
diesel fuels, deposits 1 appeared on the needles 2 of injector 3 of the injection
systems of diesel engines, in particular those of type Euro 3 to Euro 6. Thus, the
15 use of anti-wear and/or friction-modifying additives and/or additives against
deposits of the coking type have sometimes displayed resistance to lacquering that
is unsatisfactory, or even very inadequate. This is reflected in the formation of
deposit 1 generally covered by the term lacquering, which will be used hereinafter,
or using the acronym IDID (Internal Diesel Injector Deposits).
20 Within the meaning of the present invention, the phenomenon of lacquering does
not relate to the deposits that are present outside the injection system 5 or 5'
(Figures 1 and 3) and are associated with coking, which is the cause of fouling and
partial or complete clogging of the injection nozzles 4 or 4' (nozzle "coking" or
"fouling").
25 Lacquering and coking are two quite distinct phenomena both with respect to the
causes of these deposits, the conditions of appearance of these deposits and the
place where these deposits occur. Coking is a phenomenon that only appears
downstream of a diesel injection system.
As shown in Figure 3, the deposits 5' formed are characterized in that they result
30 from pyrolysis of the hydrocarbons entering the combustion chamber and have the
appearance of carbonaceous deposits. In the case of high-pressure, directinjection
diesel engines, it was found that the tendency to coking is far less
3
pronounced. This coking is simulated conventionally by the standard engine test
CEC F098-08 DW10B, especially when the fuel tested is contaminated with
metallic zinc.
In the case of engines with indirect injection, combustion of the fuel does not take
5 place directly in the combustion chamber as for engines with direct injection. As
described for example in document US4604102, there is a prechamber before the
combustion chamber in which fuel injection takes place. The pressure and
temperature in a prechamber are lower than in the combustion chamber of directinjection
engines.
10 Under these conditions, pyrolysis of the fuel produces carbon, which is deposited
on the surface of the nozzles 4' of the injectors ("throttling diesel nozzle") and clogs
the orifices 6 of the nozzles 4' (Figure 3). Only the surfaces of the nozzle 4'
exposed to the combustion gases display a risk of deposition of carbon (coking). In
terms of performance, the phenomenon of coking causes a loss of engine power.
15 Lacquering is a phenomenon that only arises in direct-injection diesel engines and
only occurs in the injection system.
As shown in Figures 1 and 2, the injectors 3 of direct-injection diesel engines
comprise a needle 2, the lift of which allows precise control of the quantity of fuel
20 injected at high pressure directly into the combustion chamber. Lacquering causes
the appearance of deposits 1, which appear specifically at the level of the needles
2 of the injectors 3 (Figures 1 and 2). The phenomenon of lacquering is associated
with the formation of soap and/or lacquer in the internal components of the
injection systems of engines for fuels of the diesel and/or bio diesel type. The
25 lacquering deposit 1 may be located on the end 4 of the needles 2 of injectors 3,
both on the head and on the body of the needles 2 of the fuel injection system but
also throughout the whole system for controlling needle lift (valves not shown) of
the injection system. This phenomenon is particularly marked for engines using
higher-grade diesel fuels. When these deposits are present in large quantities, the
30 mobility of the needle 2 of the injector 3 fouled by these deposits 1 is
compromised. Moreover, in contrast to coking, lacquering may also cause an
4
increase in engine noise and sometimes problems when starting. In fact, the parts
of the needles 2 fouled by the deposits of soap and/or of lacquer 1 may stick to the
inside walls of the injector 3. The needles 2 are then blocked and the fuel no longer
passes through.
5 Deposits of the lacquering type are generally divided into 2 types:
1. deposits that are rather whitish and pulverulent; on analysis, it is found that
these deposits consist essentially of soaps of sodium (sodium carboxylates, for
example) and/or of calcium (type 1 deposits);
2. organic deposits like coloured lacquers located on the body of the needle
10 (type 2 deposits)
Regarding the type 1 deposits, there may be several sources of sodium in
bio diesel fuels of type Bx:
• the catalysts for transesterification of vegetable oils for producing esters of
the type of (m)ethyl fatty acid esters such as sodium formate;
15 • sodium may also originate 'from the corrosion inhibitors used when
conveying petroleum products in certain pipes, such as sodium nitrite;
• finally, accidental exogenous contamination, via water or air for example,
may contribute to the introduction of sodium into fuels (sodium being a very
common element).
20 There are several possible sources of acids in fuels containing bio diesels, for
example:
o the residual acids of the biofuels (see standard EN14214, which stipulates a
maximum permitted level of acids)
o the corrosion inhibitors used when conveying petroleum products in certain
25 pipes, such as DDSA (dodecenylsuccinic anhydride) or HDSA
(hexadecenylsuccinic anhydride) or certain of their functional derivatives such as
acids.
Regarding the type 2 organic deposits, certain publications state that they may in
particular originate from reactions between deposit reducing agents/dispersants
30 used for preventing coking (for example detergents of the PIBSI type derived from
5
polyamines) and acids (which would be present among other things as impurities
of the fatty acid esters of the bio diesel).
In the publication SAE 880493, Reduced Injection Needle Mobility Caused by
Lacquer Deposits from Sunflower Oil, the authors M. Ziejewski and H.J. Goettler
5 describe the phenomenon of lacquering and its harmful consequences for the
operation of engines using sunflower oils as fuel.
In the publication SAE 2008-01-0926, Investigation into the Formation and
Prevention of Internal Diesel Injector Deposits, the authors J. Ullmann, M.
Geduldig, H. Stutzenberger (Robert Bosch GmbH) and R. Caprotti, G. Balfour
10 (Infineum) also describe the reactions between acids and deposit reducing
agents/dispersants to explain the type 2 deposits.
Moreover, in the publication SAE International, 2010-01-2242, Internal Injector
Deposits in High-Pressure Common Rail Diesel Engines, the authors S. Schwab, J.
Bennett, S. Dell, J. Galante-Fox, A. Kulinowski and Keith T. Miller explain that the
15 internal parts of the injectors are generally coated with a slightly coloured deposit
that is visible to the naked eye. Their analyses enabled them to determine that this
was predominantly sodium salts of alkenyl- (hexadecenyl- or dodecenyl-)-succinic
acids; the sodium originating from_ drying agents, from caustic liquor used in the
refinery, from tank bottom water or from seawater, and the succinic diacids being
20 used as corrosion inhibitors or present in multifunctional additive packages. Once
formed, these salts are
insoluble in low-sulphur diesel fuels and, as they are in the form of fine particles,
they pass through the diesel filters and are deposited inside the injectors. In this
publication, the development of an engine test is described and allows the deposits
25 to be reproduced.
In the publication SAE International, 2010-01-2250, Deposit Control in Modern
Diesel Fuel Injection System, the authors, R. Caprotti, N. Bhatti and G. Balfour,
also investigate the same type of internal deposits in the injectors and assert that
the appearance of deposits is not connected specifically with a type of fuel (diesel
30 or containing bio diesels) nor with' a type of vehicle (light vehicles or lorries)
equipped with modern engines (common rail). They show the performance of a
6
new deposit reducing agent/dispersant, effective on all types of deposits (coking
and lacquering).
Accumulation of deposits of the lacquering type as described above may lead to
5 the following problems:
- a slowing of the response of the fuel injector,
- sticking of the internal components, which may lead to a loss of control of
the injection time as well as of the quantity of fuel supplied per injection,
- a deterioration in the driving pleasure of the vehicle,
10 - variations of power,
- an increase in fuel consumption,
- an increase in pollutants,
- disturbance of combustion, since the quantity of fuel injected will not be
what is envisaged theoretically and the injection profile will be different,
15 - unstable idling of the vehicle,
- an increase in noise produced by the engine,
- a decline in the quality of combustion in the long term,
- a decline in the quality of atomization.
In the case when there would be a heavy deposit of the lacquering type, the
20 vehicle could have great difficulty starting, or even may no longer start at all, since
the needle allowing injection would be blocked.
SUBJECT OF THE INVENTION
The present invention makes it possible to overcome the drawbacks indicated
25 above.
In the context of his research, the applicant showed that the combination of two
particular additives allowed a surprising synergistic effect to be obtained in
particular for controlling deposits on the injectors.
30 The present invention proposes compositions of additives capable of tangibly
improving the control of deposits, in particular of the lacquering type of diesel
R2 R3
N (I)
R1
7
and/or bio diesel fuels. The present invention also relates to compositions of
additives that also improve the control of deposits of the coking type and/or the
lubricating properties of diesel and/or bio diesel fuel.
5 The present invention relates to a composition of fuel additives comprising at least:
- a first additive comprising a triazole derivative of the following formula (I):
10
in which:
. R1 is selected from the group consisting of a hydrogen atom, a linear or
branched C1 to C8 aliphatic hydrocarbon group, a carboxyl group (—CO2H),
. R2 and R5 are identical or different and represent, independently of one
15 another, a group selected from the group consisting of a hydrogen atom and a
linear or branched, saturated or unsaturated C1 to C33 aliphatic hydrocarbon
group, optionally comprising one or more oxygen atoms in the form of a
carbonyl function (-CO-) and/or carboxyl function (-CO2H), said R2 and R5
groups optionally forming together a ring with 5 to 8 atoms comprising nitrogen,
20 to which R2 is bound, it being understood that in this case R2 and R5 then
constitute one and the same linear or branched, saturated or unsaturated C1 to
C33 aliphatic hydrocarbon group, optionally substituted with one or more
oxygen atoms in the form of a carbonyl function (-CO-) and/or carboxyl function
(-CO2H),
25 . R3 and R4 are identical or different and represent, independently of one
another, a group selected from the group consisting of a hydrogen atom and a
linear or branched, saturated or unsaturated, cyclic or acyclic, aliphatic
hydrocarbon group, having from 2 to 200 carbon atoms,
25
H
/
O
8
- a second additive comprising a quaternary ammonium salt obtained by reaction
of a nitrogen-containing compound comprising a tertiary amine function with a
quaternizing agent, said nitrogen-containing compound being selected from:
a) the product of reaction of an acylating agent substituted with a hydrocarbon
5 group and a compound comprising at least one tertiary amine group and a group
selected from the primary and secondary amines and the alcohols,
b) a product of the Mannich reaction comprising a tertiary amine group; and
c) amines substituted with a polyalkene group having at least one tertiary amine
group.
10
According to a particular embodiment, the mass ratio of the first to the second
additive (first : second) is comprised between 1:100 and 100:1, preferably between
1:10 and 10:1, even more preferably between 1:2 and 2:1.
15
Advantageously, the triazole derivative has the formula (I) in which R3 and R4 are
identical or different and represent, independently of one another, a group selected
from the group consisting of a hydrogen atom and an aliphatic hydrocarbon group
having a number-average molecular weight (Mn) comprised between 200 and
20 3000.
According to a particular embodiment, the triazole derivative is represented by the
following formula (II) and/or (III):
30
in which R1, R3 and R4 are as defined above.
9
According to a further embodiment, the triazole derivative is obtained by reaction of
an aminotriazole of the following formula (IV) with a diacid of the following formula
(V) and/or a succinic anhydride of the following formula (VI):
0 R4
O
O
R3 OH
O
(IV) (V)
(VI)
in which R1, R3 and R4 are as defined above.
10
According to a particular embodiment, the quaternizing agent is selected from the
group constituted by the dialkyl sulphates, the carboxylic acid esters, the alkyl
halides, the benzyl halides, the hydrocarbon carbonates and the hydrocarbon
epoxides optionally mixed with an acid, alone or in a mixture.
15
According to another particular embodiment, the nitrogen-containing compound
comprises a product of reaction of an acylating agent substituted with a
hydrocarbon group and an amine of the following formula (VII) or (VIII):
R6 R6
\ /
R8
N — X —NH N —x —[0(CH2)m]n0H
R7
/ R7
/
20 (VII)
in which:
R6 and R7 are identical or different and represent, independently of one another, an
alkyl group having from 1 to 22 carbon atoms;
X is an alkylene group having from 1 to 20 carbon atoms;
25 m is an integer comprised between 1 and 5;
n is an integer comprised between 0 and 20; and
R8 is a hydrogen atom or an alkyl group having from 1 to 22 carbon atoms.
10
According to another particular embodiment, the composition of additives further
comprises a third additive comprising at least 50% by mass of a compound A
selected from the partial esters of polyols and of saturated or unsaturated, linear or
branched, cyclic or acyclic C4 to C36 monocarboxylic aliphatic hydrocarbons, said
5 partial esters being able to be used alone or in a mixture.
In particular, said compound A comprises x ester unit(s), y hydroxyl unit(s) and z
ether unit(s), x, y and z being integers such that x varies from 1 to 10, y varies from
1 to 10, and z varies from 0 to 6.
10
According to a further embodiment, the distribution of ester, hydroxyl and ether
units in said compound A is such that x varies from 1 to 4, y varies from 1 to 7 and
z varies from 1 to 3.
15 According to a particular embodiment, compound A is obtained by esterification
between:
- one or more C4 to C36 fatty acid(s) optionally comprising one or more ethylenic
bonds; and
- a linear or branched, cyclic or acyclic polyol optionally comprising a
20 heterocycle with 5 to 6 atoms, preferably a heterocycle with 4 to 5 carbon atoms
and one oxygen atom, substituted with hydroxyl groups.
According to a further embodiment, the fatty acids are selected from the group
constituted by stearic, isostearic, linolenic, oleic, linoleic, behenic, arachidonic,
ricinoleic, palmitic, myristic, lauric, and capric acids, used alone or in a mixture.
25
According to a particular embodiment, the polyol is selected from the polyols
comprising more than three hydroxyl functions and the polyols comprising at least
one heterocycle with 5 or 6 atoms, preferably heterocycles with 4 to 5 carbon
atoms and one oxygen atom, optionally substituted with hydroxyl groups.
30
11
According to another particular embodiment, the polyol is selected from the polyols
comprising at least two heterocycles with 4 or 5 carbon atoms and one oxygen
atom, linked by the formation of an acetal bond between a hydroxyl function of
each ring, said heterocycles optionally being substituted with hydroxyl groups.
5
According to a further embodiment, the polyol is selected from the group consisting
of erythritol, xylitol, arabitol, ribitol, sorbitol, maltitol, isomaltitol, lactitol, volemitol,
mannitol, pentaerythritol, 2-hydroxymethy1-1,3-propanediol, 1,1,1-
tri(hydroxymethyl)ethane, trimethylolpropane, sorbitan and the carbohydrates such
10 as sucrose, fructose, maltose, glucose and saccharose.
According to a particular embodiment, compound A is selected from the sorbitan
partial esters, preferably the sorbitan mono-, di- and triesters, used alone or in a
mixture, more preferably the sorbitan partial esters comprising more than 40% by
15 mass of sorbitan triesters.
According to another particular embodiment, compound A is selected from the
monoester(s) and/or diester(s) of polyglycerols having from 2 to 5 glycerol units per
molecule. In particular, compound A is selected from the monoester(s) and/or
20 diester(s) of polyglycerols derived from fatty acid(s), having more than 50% by
number of fatty chains comprising between 12 and 24 carbon atoms, preferably
compound A is selected from the monoester(s) and/or diester(s) of diglycerol
and/or of triglycerol, more preferably from the partial esters of diglycerol and/or of
triglycerol comprising at least 50% by mass of monoester(s) and/or of diester(s) of
25 oleic acid and of diglycerol.
The present invention also relates to the use of a composition of additives
according to the present invention, in a diesel fuel having a sulphur content less
than or equal to 500 ppm by mass, preferably comprising a bio diesel.
30
12
The present invention also relates to a diesel fuel having a sulphur content less
than or equal to 500 ppm by mass comprising at least 5 ppm by mass of a
composition of additives according to the present invention, preferably a fuel
comprising up to 30% by volume of bio diesel.
5
According to a particular embodiment, the fuel additionally comprises at least one
or more other additives selected from the antioxidants, combustion improvers,
corrosion inhibitors, low temperature performance additives, dyes, demulsifiers,
metal deactivators, antifoaming agents, cetane number improvers, lubricity
10 additives, co-solvents and compatibilizing agents.
In particular, the concentration by mass of each first and second additive and
optionally third additive varies from 5 to 5000 ppm.
15 The present invention also relates to the use of a diesel fuel according to the
present invention in a diesel engine, for improving the performance of said engine,
in particular for:
- limiting the deposits in said diesel engine,
- reducing the fuel consumption of said engine ("Fuel Eco" effect),
20 - minimizing the loss of power of said engine, maintaining the cleanliness of said
engine ("keep-clean" effect) by limiting the deposits of soap and/or lacquer in the
internal components of the injection systems of said engine, and/or
- cleaning the fouled internal parts of the injection system of said engine, by
removing, at least partly, the deposits of soap and/or lacquer in said internal parts
25 (curative "clean-up" effect).
According to a particular embodiment, the engine is a direct-injection engine,
preferably with a high-pressure injection system ("common-rail").
13
DETAILED DESCRIPTION
Other advantages and features will become clearer from the following description.
The particular embodiments of the invention are given by way of non-limitative
examples.
5
The present invention relates to a composition of additives comprising at least a
first and a second additive, and optionally a third additive. The present invention
also relates to the use of such a composition of additives in a diesel fuel having a
sulphur content less than or equal to 500 ppm by mass, preferably comprising a
10 bio diesel.
First additive
The first additive comprises a triazole derivative of the following formula (I):
R1
(I)
15 in which:
R1 is selected from the group consisting of a hydrogen atom, a linear or
branched C1 to C8, preferably C1 to C4, more preferably C1 to C2, aliphatic
hydrocarbon group and a carboxyl group (—CO2H). Preferably, R1 is a hydrogen
atom.
20 . R2 and R5 are identical or different and represent, independently of one
another, a group selected from the group consisting of a hydrogen atom and a
linear or branched, saturated or unsaturated C1 to C33, preferably C1 to C21
aliphatic hydrocarbon group, optionally comprising one or more oxygen atoms in
the form of a carbonyl function (-CO-) and/or carboxyl function (-CO2H), said R2
25 and R5 groups optionally forming together a ring with 5 to 8 atoms comprising
nitrogen, to which R2 is bound, it being understood that in this case R2 and R5
then constitute one and the same linear or branched, saturated or unsaturated,
C1 to C33, preferably C1 to C21 aliphatic hydrocarbon group, optionally
14
substituted with one or more oxygen atoms in the form of a carbonyl function
(-CO-) and/or carboxyl function (-CO2H).
. R3 and R4 are identical or different and represent, independently of one
another, a group selected from the group consisting of a hydrogen atom and a
5 linear or branched, saturated or unsaturated, cyclic or acyclic, aliphatic
hydrocarbon group, having from 2 to 200 carbon atoms, preferably from 14 to
200 carbon atoms, more preferably from 50 to 170 carbon atoms, even more
preferably between 60 and 120 carbon atoms.
10 It should be noted that the conventional rules of representation (bond with dashed
line and labile bond) are applied to indicate that the position of the hydrogen atom
and of the double bond of the triazole ring can change, said formula thus covering
the two possible positions.
15 According to a particular embodiment, the triazole derivative has the formula (I) in
which R3 and R4 are identical or different and represent, independently of one
another, a group selected from the group consisting of a hydrogen atom and an
aliphatic hydrocarbon group having a number-average molecular weight (Me)
comprised between 200 and 3000, preferably between 400 and 3000, more
20 preferably between 400 and 2500, even more preferably between 400 and 1500 or
between 500 and 1500. Said aliphatic hydrocarbon group is preferably a
polyisobutylene group (also called polyisobutene, denoted FIB) having a numberaverage
molecular weight (Mr) comprised between 200 and 3000, preferably
between 400 and 3000, more preferably between 400 and 2500, even more
25 preferably between 400 and 1500 or between 500 and 1500.
R3 and R4 preferably represent, respectively, a hydrogen atom and a PIB group as
described above or vice versa.
According to another particular embodiment, the triazole derivative is represented
30 by the following formula (II):
0 R4
15
in which R1, R3 and R4 are as defined above.
According to another particular embodiment, the triazole derivative is represented
5 by the following formula (III):
R1
R3 OH
in which R1, R3 and R4 are as defined above.
According to another particular embodiment, the first additive is a mixture of
10 triazole derivatives of formulae (II) and (111) as defined above. The triazole
derivative may be in the form of a mixture of derivatives in the closed form (II) and
open form (111). The mass ratio (11):(III) in said mixture of the triazole derivatives in
the closed and open form respectively may be comprised between 1:100 and
100:1, preferably between 50:10 and 90:10, more preferably between 91:9 and
15 99:1. A first additive comprising less than 10% by mass of triazole derivatives of
formula (11I) in the open form will be preferred.
A triazole derivative or mixture of formula (II) and/or (III) will be preferred, where R1
is a hydrogen atom and R3 and R4 represent respectively a hydrogen atom and a
20 PIB group as described above or vice versa (R3=PIB and R4 = H).
The triazole derivative may be obtained by any known process, in particular by
reaction of an aminotriazole of the following formula (IV) with a diacid of the
following formula (V) and/or a succinic anhydride of the following formula (VI):
16
0 R4
R1
H
N
N
0
NH2 '
R3 OH
(IV)
in which R1, R3 and R4 are as defined above.
5
Second additive
The second additive comprises a quaternary ammonium salt obtained by reaction
of a nitrogen-containing compound comprising a tertiary amine function with a
quaternizing agent. Examples of quaternary ammonium salts and the process for
10 the preparation thereof are described in patents US4253980, US3778371,
US4171959, US4326973, US4338206, US5254138 and W02010/132259 cited by
way of examples and/or incorporated by reference in the present application.
According to a first particular embodiment of the invention, the nitrogen-containing
15 compound (a) is selected from the product of reaction of an acylating agent
substituted with a hydrocarbon group, with a compound comprising at least one
tertiary amine group and a group selected from the primary and secondary amines
or the alcohols.
20 The nitrogen-containing compound (a) is preferably the product of reaction of an
acylating agent substituted with a hydrocarbon group, with a compound comprising
both an oxygen atom or a nitrogen atom capable of condensing with said acylating
agent, and a tertiary amine group.
25 The acylating agent is, advantageously, selected from the mono- or polycarboxylic
acids substituted with a hydrocarbon group and their derivatives, alone or in a
mixture. The acylating agent is, for example, selected from the succinic, phthalic
and propionic acids substituted with a hydrocarbon group.
17
The hydrocarbon substituent of the acylating agent preferably comprises at least 8,
preferably at least 12 carbon atoms, for example between 30 or 50 carbon atoms.
Said hydrocarbon substituent may comprise up to approximately 200 carbon atoms.
5 The hydrocarbon substituent of the acylating agent preferably has a numberaverage
molecular weight (Mn) comprised between 170 and 2800, for example
between 250 and 1500, more preferably between 500 and 1500, and even more
preferably between 500 and 1100. A range of values of Mn comprised between 700
and 1300 is particularly preferred, for example from 700 to 1000.
10
As examples of hydrocarbon groups substituting the acylating agent, we may
mention the n-octyl, n-decyl, n-dodecyl, tetrapropenyl, n-octadecyl, oleyl, octadecyl
or triacontyl groups.
15 The hydrocarbon substituent of the acylating agent may be obtained from homo- or
inter-polymers (for example copolymers, terpolymers) of mono- and diolefins
having from 2 to 10 carbon atoms, for example from ethylene, propylene, 1-butene,
isobutene, butadiene, isoprene, 1-hexene or 1-octene. Preferably, these olefins are
1-mono-olefins.
20
The hydrocarbon substituent of the acylating agent may also be derivatives of
halogenated analogues (for example chlorinated or brominated) of these homo- or
inter-polymers.
25 According to a variant, the hydrocarbon substituent of the acylating agent may be
obtained from other sources, for example starting from monomers of alkenes of
high molecular weight (for example, 1-tetracontene) and their chlorinated or
hydrochlorinated analogues, from aliphatic petroleum fractions, for example the
paraffin waxes, their cracked, chlorinated and/or hydrochlorinated analogues, from
30 white oils, from synthetic alkenes, for example produced by a Ziegler-Natta
18
process (for example the polyethylene greases) and from other sources known to a
person skilled in the art.
Any unsaturation in the hydrocarbon group of the acylating agent may also be
reduced or removed by hydrogenation by any known process.
5
By "hydrocarbon" group is meant any group having a carbon atom attached directly
to the rest of the molecule and mainly having an aliphatic hydrocarbon character.
Hydrocarbon groups according to the invention may also contain non-hydrocarbon
10 groups. For example, they may contain up to one non-hydrocarbon group per ten
carbon atoms provided that the non-hydrocarbon group does not significantly alter
the mainly hydrocarbon character of the group. We may mention, as examples of
such groups that are well known to a person skilled in the art, the hydroxyl groups,
the halogens (in particular the chloro and fluoro groups), the alkoxy, alkylmercapto,
15 and alkylsulphoxy groups.
Nevertheless, the hydrocarbon substituents not containing such non-hydrocarbon
groups, and having a purely aliphatic hydrocarbon character, will be preferred.
20 The hydrocarbon substituent of the acylating agent is preferably essentially
saturated, i.e. it does not contain more than one unsaturated carbon-carbon bond
for each section of ten carbon-carbon single bonds present.
The hydrocarbon substituent of the acylating agent advantageously contains not
25 more than one non-aromatic unsaturated carbon-carbon bond to every 50 carboncarbon
bonds present.
According to a preferred particular embodiment, the hydrocarbon substituent of the
acylating agent is preferably selected from the polyisobutenes known in the prior
art. Advantageously, the acylating agent substituted with a hydrocarbyl group is a
30 polyisobutenyl succinic anhydride (PIBSA).
19
The preparation of polyisobutenyl succinic anhydrides (PIBSA) is widely described
in the literature. The methods comprising the reaction between polyisobutenes
(PIB) and maleic anhydride described in documents US3361673 and US3018250
or the process comprising the reaction of a halogenated, in particular chlorinated,
5 polyisobutene (PIB) with maleic anhydride (US3172892) may be mentioned by way
of example.
According to a variant, the polyisobutenyl succinic anhydride may be prepared by
mixing a polyolefin with maleic anhydride and then passing chlorine through the
10 mixture (GB949 981).
In particular, the polyisobutenes (PIBs) referred to as highly reactive will be used.
By "highly reactive polyisobutenes (PIBs)" is meant polyisobutenes (PIB) in which
at least 50%, preferably at least 70% or more, of the terminal olefinic double bonds
15 are of the vinylidene type as described in document EP0565285. In particular, the
preferred PIBs are those having more than 80 mol% and up to 100 mol% of
terminal vinylidene groups as described in document EP1344785.
Other hydrocarbon groups comprising an internal olefin, for example such as those
20 described in application W02007/015080, may also be used.
Internal olefin means any olefin mainly containing a non-alpha double bond, which
is a beta olefin or with a higher position.
Preferably, these materials are essentially beta-olefins or olefins of higher position,
25 for example containing less than 10% by mass of alpha-olefin, advantageously less
than 5% by mass or less than 2% by mass.
The internal olefins may be prepared by isomerization of alpha-olefins by any
known process.
30
20
The compound comprising both an oxygen atom or a nitrogen atom capable of
condensing with the acylating agent and a tertiary amine group may, for example,
be selected from the group consisting of: N,N-dimethylaminopropylamine, N,Ndiethylaminopropylamine,
N,N-dimethylaminoethylamine. Said compound may
5 moreover be selected from the heterocyclic compounds substituted with
alkylamines such as 1-(3-aminopropyl)imidazole and 4-(3-aminopropyl)morpholine,
1-(2-aminoethyl)piperidine, 3,3-diamino-N-methyldipropylamine, and 3'3-
bisamino(N, N-dimethylpropylamine).
10 The compound comprising both an oxygen atom or a nitrogen atom capable of
condensing with the acylating agent and a tertiary amine group may also be
selected from the alkanolamines, including, but not limited to, triethanolamine,
trimethanolamine, N,N-dimethylaminopropanol, N,N-dimethylaminoethanol, N,Ndiethylaminopropanol,
N,N-diethylaminoethanol, N,N-diethylaminobutanol, N,N,N-
15 tris(hydroxyethyl)amine, N,N,N-tris(hydroxymethyl)amine, N,N,Ntris(
aminoethyl)amine, N, N-dibutylaminopropylamine and N,N,N'-trimethyl-N'-
hydroxyethyl-bisaminoethyl ether, N,N-bis(3-dimethylamino-propY1)-Nisopropanolamine,
N-(3-dimethylamino-propyI)-N,N-diisopropanolamine, N'-(3-
(dimethylamino)propy1)-N,N-dimethyl-1,3-propanediamine; 2-(2-
20 dimethylaminoethoxy)ethanol and N,N,N'-trimethylaminoethylethanolamine.
According to a particular embodiment, the nitrogen-containing compound (a)
comprises a product of reaction of an acylating agent substituted with a
hydrocarbon group and an amine of the following formula (VII) or (VIII):
R6 R6
\ /
R8
N — X--NH N — X —[0(CH2)m1n0H
/ R7 / R7
25
(VII) (VIII)
in which:
R6 and R7 are identical or different and represent, independently of one another,
an alkyl group having from 1 to 22 carbon atoms;
21
X is an alkylene group having from 1 to 20 carbon atoms;
m is an integer between 1 and 5;
n is an integer between 0 and 20; and
R8 is a hydrogen atom or a C1 to C22 alkyl group.
5
When the nitrogen-containing compound (a) comprises an amine of formula (VII),
R8 is advantageously a hydrogen atom or a C1 to C16 alkyl group, preferably a C1 to
'Clo alkyl group, even more preferably a C1 to C6 alkyl group. R8 may, for example,
be selected from the group consisting of hydrogen, methyl, ethyl, propyl, butyl and
10 isomers thereof. Preferably R8 is a hydrogen atom.
When the nitrogen-containing compound (a) comprises an amine of formula (VIII),
m is preferably equal to 2 or 3, more preferably equal to 2; n is preferably an
integer between 0 and 15, more preferably between 0 and 10, even more
15 preferably between 0 and 5. Advantageously, n is 0 and the compound of formula
(VIII) is an alcohol.
According to a preferred embodiment, the nitrogen-containing compound (a) is the
product of reaction of the acylating agent substituted with a hydrocarbon group with
20 the diamine of formula (VII).
R6 and R7 may represent, independently of one another, a C1 to C16 alkyl group,
preferably a C1 to C10 alkyl group to form an alkyl group. R6 and R7 may represent,
independently of one another, a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl,
octyl group or isomers thereof. Advantageously, R6 and R7 represent,
25 independently of one another, a C1 to C4 group, preferably a methyl group.
X preferably represents an alkylene group having 1 to 16 carbon atoms, preferably
from 1 to 12 carbon atoms, more preferably from 1 to 8 carbon atoms, for example
from 2 to 6 carbon atoms or from 2 to 5 carbon atoms. X advantageously
30 represents an ethylene, propylene or butylene group, in particular a propylene
group.
22
The quaternary ammonium salt of the second additive may for example be
obtained by the preparation process described in international application
W02006/135881.
5
According to a preferred variant, the nitrogen-containing compound (a) is the
product of reaction of a derivative of succinic acid substituted with a hydrocarbon
group, preferably a polyisobutenyl succinic anhydride, and an alcohol or an amine
also comprising a tertiary amine group.
10
Under certain conditions, the succinic acid derivative substituted with a
hydrocarbon group reacts with the amine also comprising a tertiary amine group to
form a succinimide (closed form).
15 According to a variant, reaction of the succinic acid derivative and the amine may
lead under certain conditions to a succinamide, i.e. a compound comprising an
amide group and a carboxylic acid group (open form).
According to another variant, an alcohol also comprising a tertiary amine group
20 reacts with the succinic acid derivative to form an ester. This ester molecule also
comprises a free carboxyl group -CO2H (open form).
Thus, in certain embodiments the nitrogen-containing compound (a) may be the
product of reaction of a succinic acid derivative and an amine or an alcohol which
25 is an ester or an amide and which further also comprises an unreacted carboxyl
group -CO2H (open form).
According to a second particular embodiment of the invention, the
nitrogen-containing compound (b) is selected from a product of the Mannich
reaction comprising a tertiary amine group.
30
23
The preparation of quaternary ammonium salts formed from a nitrogen-containing
compound, in particular from nitrogen-containing compound (b), is described for
example in document US2008/0052985.
5 The product of the Mannich reaction comprising a tertiary amine group is prepared
by reaction of a phenol substituted with a hydrocarbon group, an aldehyde and an
amine. The hydrocarbon substituent of said phenol may contain from 6 to 400
carbon atoms, advantageously from 30 to 180 carbon atoms, for example from 10
to 110, or from 40 to 110 carbon atoms.
10 The hydrocarbon substituent of said phenol may be derived from an olefin or a
polyolefin. By way of example, the alpha-olefins such as n-1-decene may be
mentioned.
The polyolefins forming the hydrocarbon substituent of the phenol may be
15 prepared by polymerization of monomers of olefins by any known process of
polymerization. Advantageously, the polyolefins are selected from the
polyisobutylenes having a number-average molecular weight (Mn) between 400
and 3000, preferably between 400 and 2500, more preferably between 400 and
1500 or between 500 and 1500.
20
The phenol substituted with a hydrocarbon group may be prepared by alkylation of
phenol with an olefin or polyolefin described above, such as a polyisobutylene or
polypropylene, using conventional methods of alkylation.
25 According to a variant, the phenol may be substituted with one or more alkyl
groups of low molecular weight, for example a phenol bearing one or more alkyl
chains with fewer than 28 carbon atoms, preferably with fewer than 24 carbon
atoms, more preferably with fewer than 20 carbon atoms, even more preferably
with fewer than 18 carbon atoms, even more preferably with 16 carbon atoms and
30 even more preferably with 14 carbon atoms.
24
A monoalkyl phenol preferably having from 4 to 20 carbon atoms, preferably from 6
to 18, more preferably from 8 to 16, even more preferably from 10 to 14 carbon
atoms, for example a phenol substituted with a C12 alkyl group, will be preferred.
5 The aldehyde used for forming the product of the Mannich reaction may comprise
from 1 to 10 carbon atoms, and is generally formaldehyde or its reactive
equivalents such as Formalin (methanol and formaldehyde) or para-formaldehyde.
The amine used for forming the product of the Mannich reaction may be a
10 monoamine or a polyamine.
As non-limitative examples, ethylamine, dimethylamine, diethylamine, n-butylamine,
dibutylamine, allylamine, isobutylamine, cocoamine, stearylamine, laurylamine,
methyllaurylamine, oleylamine, N-methyloctylamine, dodecylamine, diethanolamine,
morpholine and octadecylamine may be mentioned as monoamines.
15
The polyamines are selected from the compounds comprising two or more amine
groups. As non-limitative examples, the polyalkylene polyamines in which the
alkylene group has for example from 1 to 6, preferably from 1 to 4, more preferably
from 2 to 3 carbon atoms, may be mentioned as polyamines. The preferred
20 polyamines are the polyethylene-polyamines.
The polyamine may comprise from 2 to 15 nitrogen atoms, preferably from 2 to 10
nitrogen atoms, preferably 2 to 8 nitrogen atoms.
25 According to a preferred variant, the amine used for forming the product of the
Mannich reaction comprises a diamine, which preferably comprises a primary or
secondary amine function taking part in the Mannich reaction and a tertiary amine.
In a particular embodiment, the nitrogen-containing compound (b) comprises the
30 product obtained directly by the Mannich reaction, and comprising a tertiary amine.
25
For example, the amine comprises a single primary or secondary amine function
that is involved in the Mannich reaction and a quaternizable tertiary amine.
According to a variant, the amine comprises a primary or secondary amine capable
5 of taking part in the Mannich reaction, and a quaternizable tertiary amine.
According to another variant, the nitrogen-containing compound (b) may be
obtained by a Mannich reaction and then subjected to a reaction for obtaining a
tertiary amine, for example a process using an intermediate comprising a
10 secondary amine and obtained by the Mannich reaction, which is then modified, for
example by alkylation, to give a secondary amine.
According to a third particular embodiment of the invention, the nitrogen-containing
compound (c) is selected from the amines substituted with a polyalkene group
15 (also called polyalkylene) having at least one tertiary amine group.
Preparation of quaternary ammonium salts formed from a nitrogen-containing
compound (c) is described for example in document US2008/0113890.
20 The amines substituted with a polyalkene group having at least one tertiary amine
group may be derived from polyolefin and amine, for example ammonia, the
monoamines, the polyamines, alone or in combination. Said amines may be
prepared by any known process, for example those described in document
US2008/0113890.
25
By way of non-limitative examples, reaction of a halogenated olefinic polymer with
an amine; reaction of a hydroformylated olefin with a polyamine followed by
hydrogenation of the reaction product; conversion of a polyalkene to the
corresponding epoxide followed by conversion of the epoxide to aminated
30 polyalkene by reductive amination; hydrogenation of a f3-aminonitrile; and
26
hydroformylation of a polybutene or polyisobutylene in the presence of a cataly.st,
CO and H2 at high pressure and temperature may be mentioned.
The olefinic monomers from which the olefinic polymers are derived comprise the
5 polymerizable olefinic monomers characterized by the presence of one or more
ethylenic unsaturations, for example ethylene, propylene, 1-butene, isobutene, 1-
octene, 1,3-butadiene and isoprene. The olefinic monomers are generally
polymerizable terminal olefins. However, polymerizable internal olefinic monomers
may also be used for forming the polyalkenes.
10
As non-limitative examples, the terminal and internal olefinic monomers that may
be used for preparing the polyalkenes by any known process are: ethylene;
propylene; the butenes, including 1-butene, 2-butene and isobutylene; 1-pentene;
1-hexene; 1-heptene; 1-octene; 1-nonene; 1-decene; 2-pentene; propylene
15 tetramer; diisobutylene; isobutylene timer; 1,2-butadiene; 1,3-butadiene; 1,2-
pentadiene; 1,3-pentadiene; 1,4-pentadiene; isoprene; 5-hexadiene; 2-methyl-5-
propyl-1-hexene; 3-pentene; 4-octene and 3,3-dimethy1-1-pentene.
Amines substituted with derivatives of polyisobutylene will preferably be selected.
20
The amines used for preparing the amines substituted with a polyalkene group
may be selected from ammonia, the monoamines, the polyamines alone or in
mixtures, including mixtures of different monoamines, mixtures of different
polyamines, and mixtures of monoamines and polyamines (including the diamines).
25 Said amines comprise aliphatic, aromatic, and heterocyclic hydrocarbons and the
carbocyclic amines.
The monomers and the polyamines advantageously comprise at least one primary
or secondary amine.
30 The monoamines are generally substituted with a hydrocarbon group having from 1
to approximately 50 carbon atoms, preferably from 1 to 30 carbon atoms. The
27
saturated aliphatic hydrocarbon substituents are particularly preferred. As
examples, methylamine, ethylamine, diethylamine, 2-ethylhexylamine, di(2-
ethylhexyl)amine, n-butylamine, di-n-butylamine, allylamine, isobutylamine,
cocoamine, stearylamine, laurylamine, methyllaurylamine and oleylamine may be
5 mentioned.
The aromatic monoamines comprise the monoamines in which a carbon atom
having an aromatic cyclic structure is attached directly to the amine nitrogen.
Examples of aromatic monoamines comprise aniline, di(para-methylphenyl)amine,
10 naphthylamine and N-(n-butyl)aniline.
Examples of aromatic monoamines substituted with aliphatic, cycloaliphatic and
heterocyclic hydrocarbon groups comprise para-dodecylaniline, cyclohexylnaphthylamine
and thienylaniline, respectively.
15 The monoamines according to the present invention also comprise the
hydroxyamines. By way of example, ethanolamine, di-3-propanolamine, 4-
hydroxybutylamine, diethanolamine and N-methyl-2-hydroxypropylamine may be
mentioned.
20 The polyamines may also be selected from the amines substituted with polyalkene
groups. The polyamine may be aliphatic, cycloaliphatic, heterocyclic or aromatic.
By way of example, the alkylene polyamines, the polyamines with hydroxy
substitution, the arylpolyamines and the heterocyclic polyamines may be
mentioned. The ethylenic polyamines are preferred for reasons of cost and
25 efficiency.
The polyamines with hydroxy substitution comprise the hydroxyalkylated alkene
polyamines having one or more hydroxyalkyl substituents on the nitrogen atoms
and that may be prepared by reaction of the alkene polyamines with one or more
30 alkene oxides. By way of example, N-(2-hydroxyethyl)ethylenediamine, N,N-bis(2-
hydroxyethyl)ethylenediamine, 1-(2-hydroxyethyl)piperazine, monohydroxypropyl28
diethylenetriamine, dihydroxypropyl-tetraethylenepentamine and N-(3-
hyd roxybutyl)-tetramethylenediamine may be mentioned.
The arylpolyamines are analogues of the aromatic monoamines described above
5 except for the presence in their structure of another amino nitrogen. By way of
example, N,N'-di-n-butyl-para-phenylenediamine and bis(paraaminophenyl)
methane may be mentioned.
The mono- and heterocyclic polyamines will be known to a person skilled in the art.
10 By way of example, N-aminopropylmorpholine, N-aminoethylpiperazine, and N,N'-
diaminoethylpiperazine may be mentioned. The hydroxy-heterocyclic polyamines
may also be used, for example N-(2-hydroxyethyl)cyclohexylamine, 3-
hydroxycyclopentylamine, parahydroxy-aniline and N-hydroxyethylpiperazine.
15 Examples of amines substituted with polyalkene groups may comprise:
polypropylene amine, polybutene amine, N,N-dimethyl-polyisobutylene-amine, Npolybutene-
morpholine, N-polybutene-ethylenediamine, N-polypropylene
trimethylenediamine, N-polybutene-diethylenetriamine, N',N'-polybutenetetraethylenepentamine
and N,N-dimethyl-N'-polypropylene-1,3-propylenediamine.
20
The number-average molecular weight (Me) of the amines with polyalkene
substitution may range from 500. to 5000, preferably from 500 to 3000, for example
from 1000 to 1500.
25 All the amines with polyalkene substitution described above that are primary or
secondary amines may be alkylated to form tertiary amine functions using
alkylating agents by any known process.
The quaternary ammonium salt of the second additive according to the present
30 invention is obtained directly by reaction between the nitrogen-containing
29
compound described above comprising a tertiary amine function and a
quaternizing agent.
According to a particular embodiment, the quaternizing agent is selected from the
5 group constituted by the dialkyl sulphates, the carboxylic acid esters; the alkyl
halides, the benzyl halides, the hydrocarbon carbonates, and the hydrocarbon
epoxides optionally mixed with an acid, alone or in a mixture.
For fuel applications, it is often desirable to reduce the content of halogen, sulphur
10 and the phosphorus-containing compounds.
Thus, if a quaternizing agent containing such an element is used, it may be
advantageous to carry out a subsequent reaction for exchange of the counter-ion.
For example, a quaternary ammonium salt formed by reaction with an alkyl halide
15 may then be reacted with sodium hydroxide and the sodium halide salt may be
removed by filtration.
The quaternizing agent may comprise halides such as chloride, iodide or bromide;
hydroxides; sulphonates; bisulphites; alkyl sulphates such as dimethyl sulphate;
20 sulphones; phosphates; C1-C12 alkyl phosphates; C1-C12 dialkyl phosphates;
borates; C1-C12 alkyl borates; nitrites; nitrates; carbonates; bicarbonates;
alkanoates; C1-C12 0,0-dialkyldithiophosphates, alone or in a mixture.
According to a particular embodiment, the quaternizing agent may be derived from
25 dialkyl sulphates such as dimethyl sulphate, from N-oxides, from sulphones such
as propane- and butane-sulphone, from alkyl halides, from acyl or from aralkyl
such as methyl and ethyl chloride, benzyl bromide, iodide or chloride, and the
hydrocarbon carbonates (or alkyl carbonates). If the acyl halide is benzyl chloride,
the aromatic ring is optionally substituted with one or more alkyl or alkenyl groups.
30 The hydrocarbon groups (alkyls) of the hydrocarbon carbonates may contain from
1 to 50, from 1 to 20, from 1 to 10 or 1 to 5 carbon atoms per group.
30
According to a particular embodiment, the hydrocarbon carbonates contain two
hydrocarbon groups, which may be identical or different. As an example of
hydrocarbon carbonates, dimethyl or diethyl carbonate may be mentioned.
According to a particular embodiment, the quaternizing agent is selected from the
hydrocarbon epoxides represented by the following formula (IX):
R9
R11
5
10 R1 12
(IX)
in which R9, R10, R11 and R12 may be identical or different and represent,
independently, a hydrogen atom or a C1-050 hydrocarbon group. By way of nonlimitative
example, styrene oxide, ethylene oxide, propylene oxide, butylene oxide,
15 stilbene oxide and the C1-050 epoxides may be mentioned. Styrene oxide is
particularly preferred.
Typically, hydrocarbon epoxides of this kind are used as quaternizing agent in
combination with an acid, for example with acetic acid.
20
Nevertheless, in the particular embodiment described above involving the
nitrogen-containing compound (a) constituted by a substituted succinamide
comprising both an amide or ester function and a carboxylic acid function (open
form), the hydrocarbon epoxide may be used alone as quaternizing agent without
25 additional acid. Without being bound by this hypothesis, it would seem that the
presence of the carboxylic acid function in the molecule promotes formation of the
quaternary ammonium salt.
In such a particular embodiment, not using additional acid, a protic solvent is used
30 for preparing the quaternary ammonium salt. By way of example, the protic
solvents such as water, the alcohols (including the polyhydric alcohols) may be
31
used alone or in a mixture. The preferred protic solvents have a dielectric constant
greater than 9. The appropriate quaternary ammonium salts prepared from amides
or esters and derivatives of succinic acid are described in W02010/132259.
5 According to a particular embodiment, the quaternizing agent comprises a
compound of formula (X):
0
R14
(X)
R1 o
10 in which R13 is an alkyl, alkenyl, aryl and aralkyl group, optionally substituted, and
R14 is a C1 to C22 alkyl, aryl or alkylaryl group.
The compound of formula (X) is a carboxylic acid ester capable of reacting with a
tertiary amine to form a quaternary ammonium salt. Compounds of formula (X) are
15 selected, for example, from the esters of carboxylic acids having a pKa of 3.5 or
less. The compound of formula (X) is preferably selected from the esters of
substituted aromatic carboxylic acid, of a-hydroxycarboxylic acid and of
polycarboxylic acid.
20 According to a particular embodiment, the ester is an ester of substituted aromatic
carboxylic acid of formula (X) in which R13 is a substituted aryl group. Preferably,
R13 is a substituted aryl group having 6 to 10 carbon atoms, preferably a phenyl or
naphthyl group, more preferably a phenyl group. R13 is advantageously substituted
with one or more groups selected from the carboalkoxy, nitro, cyano, hydroxy, SR15
25 and NR15 R16 radicals. Each of the R15 and R16 groups may be a hydrogen atom or
an alkyl, alkenyl, aryl or carboalkoxy group, optionally substituted. Each of the R15
and R16 groups represents, advantageously, a hydrogen atom or a C1 to C22 alkyl
group, optionally substituted, preferably a hydrogen atom or a C1 to C16 alkyl group,
more preferably a hydrogen atom or a C1 to C10 alkyl group, even more preferably
30 a hydrogen atom or a C1 to C4 alkyl group. R15 is preferably a hydrogen atom and
32
R16 a hydrogen atom or a C1 to C4 group. Advantageously, R15 and R16 are both a
hydrogen atom.
According to a particular embodiment, R13 is an aryl group substituted with one or
5 more groups selected from the hydroxyl, carboalkoxy, nitro, cyano and NH2
radicals. R13 may be a polysubstituted aryl group, for example trihydroxyphenyl.
Advantageously, R13 is a monosubstituted aryl group, preferably ortho-substituted.
R13 is, for example, substituted with a group selected from the OH, NH2, NO2 or
COOMe radicals, preferably OH or NH2. R13 is preferably a hydroxy-aryl group, in
10 particular 2-hydroxyphenyl.
According to a particular embodiment, R14 is an alkyl or alkylaryl group. R14 may be
a C1 to C16, preferably C1 to C10, advantageously C1 to C8 alkyl group. R14 may be
a C1 to C16, preferably C1 to C10, advantageously C1 to C8 alkylaryl group. R14 may
15 for example be selected from the methyl, ethyl, propyl, butyl, pentyl, benzyl groups
or isomers thereof. Preferably, R14 is a benzyl or methyl group, more preferably
methyl.
A particularly preferred compound of formula (X) is methyl salicylate.
20
According to a particular embodiment, the compound of formula (X) is an ester of
an a-hydroxycarboxylic acid of the following formula:
R17
R1 OR14
OH
25 in which R1.7 and R18, are identical or different, and are selected independently from
the group consisting of the hydrogen atom, the alkyl, alkenyl, aryl or aralkyl groups.
Such compounds are described for example in document EP 1254889.
33
Examples of compounds of formula (X) in which R13C00 is the residue of an ahydroxycarboxylic
acid comprise the methyl, ethyl, propyl, butyl, pentyl, hexyl,
phenyl, benzyl or ally! esters of 2-hydroxy-isobutyric acid; the methyl, ethyl, propyl,
butyl, pentyl, hexyl, benzyl, phenyl or ally! esters of 2-hydroxy-2-methylbutyric acid;
5 the methyl, ethyl, propyl, butyl, pentyl, hexyl, benzyl, phenyl or ally' esters of 2-
hydroxy-2-ethylbutyric acid; the methyl, ethyl, propyl, butyl, pentyl, hexyl, benzyl,
phenyl or allyl esters of lactic acid and the methyl, ethyl, propyl, butyl, pentyl, hexyl,
allyl, benzyl or phenyl esters of glycolic acid. From the above, the preferred
compound is methyl-2-hydroxyisobutyrate.
10
According to a particular embodiment, the compound of formula (X) is an ester of a
polycarboxylic acid comprising the dicarboxylic acids and the carboxylic acids
having more than two acid functions. The carboxyl functions are preferably all in
the esterified form. The preferred esters are the C1 to C4 alkyl esters.
15
The compound of formula (X) may be selected from the oxalic acid diesters, the
phthalic acid diesters, the maleic acid diesters, the malonic acid diesters or the
citric acid diesters. Preferably, the compound of formula (X) is dimethyl oxalate.
According to a preferred variant, the compound of formula (X) is a carboxylic acid
20 ester having a pKa below 3.5. For the cases where the compound comprises more
than one acid group, reference will be made to the first dissociation constant.
The compound of formula (X) may be selected from one or more carboxylic acid
esters selected from oxalic acid, phthalic acid, salicylic acid, maleic acid, malonic
25 acid, citric acid, nitrobenzoic acid, aminobenzoic acid and 2,4,6-trihydroxybenzoic
acid. The preferred compounds of formula (X) are dimethyl oxalate, 2-methyl
nitrobenzoate and methyl salicylate.
According to an especially preferred embodiment, the quaternary ammonium salt
30 according to the invention is formed by reaction of 2-methylhydroxybenzoate or
styrene oxide with the reaction product of a polyisobutenyl succinic anhydride the
34
polyisobutylene group (P113) of which has a number-average molecular weight (Mn)
between 700 and 1000 and dimethyl-aminopropylamine.
According to a preferred particular embodiment, the composition of additives
5 comprises the first additive as described above preferably comprising a triazole
derivative of formula (II) and/or (III) and the second additive comprising a
quaternary ammonium salt obtained from the nitrogen-containing compound (a)
described above.
10 Third additive
According to a particular embodiment, the composition of additives described
above may further comprise a third additive. The third additive comprises at least
50% by mass of a compound A selected from the partial esters of polyols and of
saturated or unsaturated, linear or branched, cyclic or acyclic, C4 to C36, preferably
15 C12-C24, more preferably C16-C20, monocarboxylic aliphatic hydrocarbons, said
partial esters being able to be used alone or in a mixture.
Compound A preferably comprises x ester units, y hydroxyl units and z ether units,
x, y and z being integers such that x varies from 1 to 10, y varies from 1 to 10, and
20 z varies from 0 to 6.
According to a particular embodiment, x varies from 1 to 10, y varies from 3 to 10,
and z varies from 0 to 6.
25 According to another particular embodiment x varies from 1 to 4, y varies from 1 to
7 and z varies from 1 to 3. Advantageously, x varies from 2 to 4.
The synthesis of partial esters of polyols is known per se; they may for example be
prepared by esterification of fatty acid(s) and of linear and/or branched polyols
30 optionally comprising (hetero)cycles with 5 to 6 atoms bearing hydroxyl functions.
35
Generally this type of synthesis leads to a mixture of mono-, di-, tri- and optionally
of tetra-esters as well as small quantities of fatty acid(s) and unreacted polyols.
According to a particular embodiment, compound A is obtained by esterification of
5 one or more C4 to C36 fatty acid(s), preferably C10-C24, more preferably C12-C24,
optionally comprising one or more ethylenic bonds, and of a linear or branched,
cyclic or acyclic polyol, optionally comprising a heterocycle with 5 to 6 atoms,
preferably a heterocycle with 4 to 5 carbon atoms and one oxygen atom,
substituted with hydroxyl groups.
10
The fatty acids are selected advantageously from the group constituted by stearic,
isostearic, linolenic, oleic, linoleic, behenic, arachidonic, ricinoleic, palmitic,
myristic, lauric, and capric acids, used alone or in a mixture.
15 The fatty acids may originate from transesterification or saponification of vegetable
oils and/or of animal fats. The preferred vegetable oils and/or animal fats will be
selected as a function of their concentration of oleic acid. Reference may be made
for example to Table 6.21 of chapter 6 of the work Carburants & Moteurs [Fuels &
Engines] by J.C. Guibet and E. Faure, 2007 edition, which gives the compositions
20 of several vegetable oils and animal fats.
The fatty acids may also originate from fatty acids derived from tall oil (Tall Oil
Fatty Acids), which comprise a majority quantity of fatty acids, typically greater than
or equal to 90% by mass, as well as smaller quantities of resin acids and
25 unsaponifiables, i.e. in quantities generally below 10%.
The polyol will preferably be selected from the linear or branched polyols
comprising more than three hydroxyl functions and the polyols comprising at least
one ring of 5 or 6 atoms, preferably a heterocycle with 4 to 5 carbon atoms and
30 one oxygen atom, optionally substituted with hydroxyl groups, used alone or in a
mixture.
36
According to a preferred variant, the polyol is selected from the polyols comprising
at least one ring of 5 or 6 atoms, preferably a heterocycle with 4 to 5 carbon atoms
and one oxygen atom, optionally substituted with hydroxyl groups, used alone or in
5 a mixture.
According to another variant, the polyol is selected from the polyols comprising at
least two heterocycles with 4 or 5 carbon atoms and one oxygen atom, linked by
the formation of an acetal bond between a hydroxyl function of each ring, said
10 heterocycles optionally being substituted with hydroxyl groups.
The polyol is, in particular, selected from the group consisting of erythritol, xylitol,
arabitol, ribitol, sorbitol, maltitol, isomaltitol, lactitol, volemitol, mannitol,
pentaerythritol, 2-hydroxymethy1-1,3-propandediol, 1,1,1-tri(hydroxymethyl)ethane,
15 trimethylolpropane, sorbitan and the carbohydrates such as sucrose, fructose,
maltose, glucose and saccharose, preferably sorbitan*.
According to a particular embodiment, compound A is selected from the sorbitan
partial esters, preferably the sorbitan di-, mono- and triesters, used alone or in a
20 mixture.
According to a variant, compound A is selected from the sorbitan partial esters
comprising more than 40% by mass of sorbitan triesters, preferably more than 50%
by mass.
25
According to another variant, compound. A is selected from the sorbitan partial
esters comprising more than 20% by mass of sorbitan monoesters and/or more
than 20% by mass of sorbitan diesters, preferably more than 20% by mass of
sorbitan monoesters and/or more than 30% by mass of sorbitan diesters, more
30 preferably more than 25% by mass of sorbitan monoesters and/or more than 35%
by mass of sorbitan diesters.
37
According to another particular embodiment, compound A is selected from the
monoester(s) and/or diester(s) of polyglycerols derived from fatty acid(s), having
more than 50% by number of fatty chains comprising between 12 and 24 carbon
5 atoms. Such polyglycerols, described in document W02013/120985, are cited by
way of example and/or incorporated by reference in the present application.
Compound A is preferably selected from the monoester(s) and/or diester(s) of
diglycerol and/or of triglycerol.
10
In particular, the partial esters of diglycerol and/or of triglycerol comprise at least 50%
by mass of monoester(s) and/or of diester(s) of oleic acid and of diglycerol, thus of
diglycerol mono-oleate(s) (DGMO) and/or of diglycerol dioleate(s) (DGDO), either
at least 50% by mass of mono- and/or diester(s) of oleic acid and of triglycerol, or
15 at least 50% by mass of mono- and/or diester(s)
of oleic acid and of diglycerol and/or of triglycerol.
According to a particular embodiment, each of the first, second and third additives
are constituted solely by their respective active ingredient, namely the triazole
20 derivative in the case of the first additive, the quaternary ammonium salt in the
case of the second additive and compound A in the case of the third additive.
According to a particular embodiment, the composition of additives comprises the
first additive, the quaternary ammonium salt obtained from the nitrogen-containing
25 compound (a) and a compound A selected from the sorbitan partial esters
described above, preferably a sorbitan triester.
According to a variant, the composition of additives comprises the first additive, the
quaternary ammonium salt obtained from the nitrogen-containing compound (a)
30 and a compound A selected from the monoesters and/or diesters of polyglycerols
derived from fatty acid as described above.
38
According to another particular embodiment, the composition of additives
comprises the first additive, the quaternary ammonium salt obtained from the
nitrogen-containing compound (b) and a compound A selected from the sorbitan
5 partial esters described above, preferably a sorbitan triester.
According to a variant, the composition of additives comprises the first additive, the
quaternary ammonium salt obtained from the nitrogen-containing compound (b)
and a compound A selected from the monoesters and/or diesters of polyglycerols
10 derived from fatty acid as described above.
According to another particular embodiment, the composition of additives
comprises the first additive, the quaternary ammonium salt obtained from the
nitrogen-containing compound (c) and a compound A selected from the sorbitan
15 partial esters described above, preferably a sorbitan triester.
According to a variant, the composition of additives comprises the first additive, the
quaternary ammonium salt obtained from the nitrogen-containing compound (c)
and a compound A selected from the monoesters and/or diesters of polyglycerols
20 derived from fatty acid as described above.
The composition of additives described above may also comprise one or more
other conventional additives. As examples, we may mention antioxidants,
combustion improvers, corrosion inhibitors, low temperature performance additives,
25 dyes, demulsifiers, metal deactivators, antifoaming agents, cetane number
improvers, lubricity additives, co-solvents and compatibilizing agents.
Non-exhaustively, the other functional additive or additives may be selected from:
- combustion improvers; the cetane number improvers may be mentioned, in
30 particular (but non-limitatively) selected from the alkyl nitrates, preferably 2-
39
ethylhexyl nitrate, the aryl peroxides, preferably benzyl peroxide, and the alkyl
peroxides, preferably ditert-butyl peroxide;
- antioxidant additives, such as aliphatic and aromatic amines, the hindered
phenols, such as BHT, BHQ;
5 - demulsifiers;
- antistatic additives or conductivity improvers;
- dyes;
- antifoaming additives, in particular (but non-limitatively) selected for example
from the polysiloxanes, the alkoxylated polysiloxanes, and the amides of fatty acids
10 derived from vegetable or animal oils; examples of such additives are given in
EP861182, EP663000, EP736590;
- anticorrosion additives such as the ammonium salts of carboxylic acids;
- metal chelating and/or sequestering agents, such as the triazoles, the
disalicylidene alkylene diamines, and in particular N,N'-bis(salicylidene)-1,3-
15 propanediamine;
- low temperature performance additives and in particular cloud point improvers,
in particular (but non-limitatively) selected from the group constituted by the longchain
olefin/(meth)acrylic ester/maleimide terpolymers, and the polymers of esters
of fumaric/maleic acids. Examples of such additives are given in EP71513,
20 EP100248, FR2528051, FR2528051, FR2528423, EP112195, EP172758,
EP271385, EP291367; the antisedimentation additives and/or paraffin dispersants
in particular (but non-limitatively) selected from the group constituted by the
copolymers of (meth)acrylic acid/alkyl (meth)acrylate amidated by a polyamine, the
alkenyl succinimides derived from polyamines, the derivatives of phthalamic acid
25 and double-chain fatty amine; alkylphenol/aldehyde resins; examples of such
additives are given in EP261959, EP593331, EP674689, EP327423, EP512889,
EP832172; US2005/0223631; US5998530; W093/14178; the multifunctional
additives for low-temperature operation in particular selected from the group
constituted by the polymers based on olefin and alkenyl nitrate as described in
30 EP573490;
40
- other additives improving low temperature performance and filterability (CFI),
such as the EVA and/or EVP copolymers;
acidity neutralizers such as the cyclic alkylamines;
- markers, in particular the markers imposed by the regulations, for example dyes
5 specific to each type of fuel;
- perfuming or odour-masking agents, such as those described in EP1 591514;
- lubricity additives, anti-wear agents and/or friction modifiers other than those
described above, in particular (but non-limitatively) selected from the derivatives of
mono- and polycyclic carboxylic acids.
10
The composition of additives according to the present invention may be
incorporated in the fuel by any known process. By way of example, the
composition of additives may be incorporated in the form of a concentrate
comprising said composition and a solvent, compatible with the fuel, the
15 composition being dispersed or dissolved in the solvent. Concentrates of this kind
generally contain from 1 to 95%, preferably from 20 to 95% by mass of solvents.
The composition of additives typically comprises between 5 and 99%, preferably
between 5 and 80% by mass of additives.
20
The solvents are organic solvents, which generally contain hydrocarbon solvents.
By way of examples of solvents, petroleum fractions, such as naphtha, kerosene,
heating oil; aliphatic and/or aromatic hydrocarbons such as hexane, pentane,
decane, pentadecane, toluene, xylene, and/or ethylbenzene and the
25 alkoxyalkanols such as 2-butoxyethanol and/or mixtures of hydrocarbons and
optionally of co-solvents or compatibilizing agents, such as 2-ethylhexanol, decanol,
isodecanol and/or isotridecanol may be mentioned.
The composition of additives as described above may be used as a fuel additive. In
30 particular, the composition of additives according to the invention is particularly
41
suitable for use in a diesel fuel having a sulphur content less than or equal to 500
ppm by mass, preferably comprising a bio diesel.
The diesel fuels are liquid fuels for compression engines. By diesel fuel is meant
5 fuels comprising middle distillates with a boiling point between 100 and 500°C;
their wax appearance temperature WAT is often greater than or equal to -20°C,
and generally comprised between -15°C and +10°C. These distillates are mixtures
of bases that may be selected for example from distillates obtained by direct
distillation of petroleum or of crude hydrocarbons, vacuum distillates, hydrotreated
10 distillates, distillates originating from catalytic cracking and/or hydrocracking of
vacuum distillates, distillates resulting from conversion processes of the ARDS
type (by desulphurization of atmospheric residue) and/or from visbreaking.
The diesel fuels according to the invention may also contain light cuts such as the
gasolines originating from distillation, from catalytic or thermal cracking units,
15 alkylation, isomerization, desulphurization units, steam cracking units.
Moreover, the diesel fuels may contain new sources of distillates, among which the
following may in particular be mentioned:
- the heaviest cuts originating from processes of cracking and visbreaking with high
concentrations of heavy paraffins, comprising more than 18 carbon atoms,
20 - the synthetic distillates resulting from gas conversion such as those resulting from
the Fischer-Tropsch process,
- the synthetic distillates resulting from treatment of biomass of vegetable and/or
animal origin, such as in particular NexBTL, used alone or in a mixture,
- the coker diesels.
25 The diesel fuel according to the invention may also comprise or be solely
constituted by one or more biofuels. By biofuel is meant the fuels obtained from
organic matter (biomass), in contrast to the fuels originating from fossil resources.
By way of examples of known biofuels, bio diesels (also called biodiesels) and
alcohols may be mentioned.
42
The alcohols, such as methanol, ethanol, butanols, ethers (MTBE, ETBE, etc.) are
generally used in a mixture with gasoline fuels, but sometimes with heavier fuels of
the diesel type.
5 Biodiesel or bio gas oil is an alternative to the standard fuel for diesel engines. This
biofuel is obtained from vegetable or animal oil (including used cooking oils)
transformed by a chemical process called transesterification, causing this oil to
react with an alcohol in order to obtain fatty acid esters. With methanol and ethanol,
fatty acid methyl esters (FAME) and fatty acid ethyl esters (FAEE) are obtained
10 respectively.
By way of examples of vegetable and/or animal oils and/or their esters, the
Vegetable Oil or Fatty Acid Methyl or Ethyl Esters (VOME, VOEE, FAME, FAEE)
may be mentioned; for the vegetable and/or animal oils, the hydrotreated and/or
hydrocracked and/or hydrodeoxygenated (HDO) vegetable and/or animal oils may
15 be mentioned.
Mixtures of middle distillates of fossil origin and of bio diesel are generally denoted
by the letter "B" followed by a number indicating the percentage of bio diesel
contained in the diesel. Thus, a B99 contains 99% of bio diesel and 1% of middle
20 distillates of fossil origin; B20, 20% of bio diesel and 80% of middle distillates of
fossil origin etc.
A distinction is therefore made between the diesel fuels of type BO, which do not
contain oxygenated compounds, and the bio diesel of type Bx, which contain x%
(v/v) of vegetable oil or fatty acid esters, most often methyl esters (VOME or
25 FAME). When bio diesel is used .alone in engines, the fuel is denoted by the term
B100.
In the remainder of the present application, the term "diesel fuel" will be used in the
broad sense to cover all the fuels described above.
30 Diesel fuel preferably has a sulphur content less than or equal to 500 ppm by mass,
advantageously less than or equal to 100 ppm by mass, and may reach a content
43
less than or equal to 50 ppm by mass, or even less than or equal to 10 ppm by
mass (this is case for current diesel fuels for vehicles, the sulphur content of which
according to European standard EN 590 currently in force must be less than or
equal to 10 ppm by mass).
5
The diesel fuel advantageously comprises up to 30% by volume of bio diesel,
preferably up to 20% by volume, more preferably up to 10% by volume.
The composition of additives is preferably incorporated in the fuel so as to obtain a
10 concentration by mass of each additive contained in said composition in the range
from 5 to 5000 ppm, preferably from 20 to 500 ppm, more preferably from 30 to
250 ppm in the fuel. The concentration by mass is calculated relative to the total
mass of the fuel.
15 In particular, the concentration by mass of each first and second additive and
optionally third additive varies from 5 to 5000 ppm, and preferably between 20 and
500 ppm, more preferably between 30 and 250 ppm.
A person skilled in the art will easily adapt the concentration of the composition of
20 additives according to the invention as a function of optional dilution of the
additives in a solvent, to obtain the desired concentration of each functional
additive in the final fuel.
The fuel preferably comprises at least 5 ppm by mass, preferably at least 100 ppm
25 by mass of the composition of additives according to the invention. It will be
possible for up to 10% by mass, preferably up to 1% by mass, more preferably up
to 0.5% by mass of additives, including the composition of additives, to be
incorporated in a fuel.
44
The mass ratio of the first to the second additive (first : second) is between 1:100
and 100:1, preferably between 1:10 and 10:1, even more preferably between 1:2
and 2:1.
5 The mass ratio of the second to the third additive (second : third) is between 1:100
and 1:1, preferably between 1:10 and 1:1, even more preferably between 1:5 and
1:1.
The diesel fuel described above may be used in a diesel engine, to improve the
10 performance of said engine, in particular to limit the deposits in said engine,
preferably in a direct-injection engine, more preferably when the engine is
equipped with a high-pressure injection system ("common-rail").
Use of such a fuel incorporating the composition of additives according to the
15 present invention makes it possible to reduce the fuel consumption of the diesel
engine ("Fuel Eco" effect), and in particular makes it possible to minimize the loss
of power of said engine.
The present invention also relates to a process for maintaining the cleanliness of a
20 diesel engine ("keep-clean" effect) by limiting the deposits of soap and/or lacquer
in the internal components of the injection systems of said engine and/or for
cleaning the fouled internal parts of the injection system of said engine, by
removing, at least partly, the deposits of soap and/or lacquer in said internal parts
(curative "clean-up" effect).
25
Said process comprises the combustion of a composition of additives according to
the present invention in a diesel engine, in particular in a direct-injection engine,
preferably with a high-pressure injection system ("common-rail").
EXAMPLES
30 Reagents
- N,N-bis(2-ethylhexyl)-1,2,4-triazole-1-methanamine (CAS 91273-04-0)
45
- Polyisobutenyl succinic anhydride (PIBSA) with number-average molecular
weight Mn of 1100 (GPC) marketed by the company BASF under the trade name
"Glissopal*SAO"
- 3-amino-1,2,4-triazole (CAS 61-82-5).
5
Table 1: Composition by mass of sorbitan partial esters SPE1 and SPE2,
determined by gel permeation chromatography (GPC)
Component SPE1 SPE2
(%) (%)
Sorbitol 1.4 0.3
Free fatty acids 1.2 5.9
Sorbitan monooleate 24.7 7.1
Sorbitan dioleate 41.3 30.4
Sorbitan trioleate 28.7 54.3
Unidentified compounds 2.7 1.9
Example 1 - Synthesis of diglycerol partial ester additives: DGM01 and DGMO2
10
In the presence of a catalyst of the Me0Na type, 90 g of diglycerol is reacted at
170°C with 500 g of oleic sunflower oil (concentration of oleic acid equivalent under
reduced pressure of 300 mbar (0.03 MPa) for 6 hours).
The procedure is shown below once again for preparing a second sample of
product.
15
Table 2: Composition by mass of the products obtained DGMO1 and DGMO2
determined by gel permeation chromatography (GPC)
46
Component DGMO 1 DGMO 2
Diglycerol monoester 24.7 31.4
Diglycerol diester 41.2 30.2
Diglycerol triester 18.6 14.4
Diglycerol tetraester 6.6 6.4
Monoglyceride 2.4 nd
Dig lyceride 1 2.1
Diglycerol nd 3.3
Oleic sunflower methyl ester 5.3 6.4
nd = not determined
Example 2: Synthesis of 3-polyisobutene succinimide-1,2,4-triazole
A 500 mL flask is loaded with 100g of polyisobutenyl succinic anhydride (PIBSA)
5 with 84% of active ingredient (76.64 mmol), and 26.3g of an aromatic solvent of the
brand "Solvesso 150ND" is added. After the assembly is equipped with a Dean
Stark and placed under a nitrogen atmosphere, the reaction medium is heated to
140°C, under vigorous stirring, and then 5.15 g (0.8eq./61.31 mmol) of 3-amino-
1,2,4-triazole is introduced. It is then heated under reflux for 4h in order to remove
10 1.10 mL of water in the Dean Stark. It is cooled to ambient temperature and then
additional solvent Solvesso 150ND is added, to obtain a product with 50% of active
ingredient. 202.4g of a clear brown liquid with 50% of active ingredient (50.8%
measured) is obtained.
15 The product obtained is a mixture of triazole derivatives in the open form (formula II
with R1 and R3=H and R4=PIB) and in the closed form (formula III with R1 and
R3=H and R4=PIB or R1 and R3= PIB and R4 =H).
The ratio of the percentages by mass, open form/closed form, determined by GPC
analysis is 95:5.
20
Example 3: Synthesis of a quaternary ammonium salt QAS
. Preparation of a nitrogen-containing compound (a)
47
500g (0.38 mol) of polyisobutenyl succinic anhydride (PIBSA) is heated to 70°C,
introduced into a reactor equipped with a Dean Stark and placed under a nitrogen
atmosphere. 76.9g of heptane and then 52.3g (0.51 mol/1.34eq.) of
dimethylaminopropylamine (DMAP) are added to the reactor, maintaining the
5 reaction temperature at 70°C during introduction. The reaction medium is kept at
70°C for 1h. The reaction medium is cooled to ambient temperature. The
intermediate is recovered.
. Quaternization of the tertiary amine of the nitrogen-containing compound (a)
470g of the intermediate is placed in a new 2L reactor equipped with a condenser.
10 Then 180.6g of 2-ethylhexanol is introduced and the reaction medium is stirred and
heated to 55°C under a nitrogen atmosphere. 40.2g (0.69 mol) of propylene oxide
is then introduced gradually into the mixture by means of a syringe pump over a
period of 4 hours, maintaining the reaction temperature at 55°C. The mixture is
maintained at this temperature for 16h. After the medium has cooled, the reaction
15 product, mainly comprising the derivative of quaternary ammonium salt QAS, is
recovered.
Samples of said reaction product QAS were analysed qualitatively by infrared
absorption spectroscopy (IR), mass spectrometry and NMR. This qualitative
20 analysis made it possible to determine the main components present in the
reaction product by comparison with reference spectra and taking into account the
degrees of dilution.
A quantitative analysis was also performed on dry residue by 13C NMR, using an
internal standard.
25
The composition by mass of the product QAS measured using the techniques
described above is shown in Table 3 below.
48
Table 3
Components % by mass
Quaternary ammonium salt - succinamide form 69.5
Quaternary ammonium salt - succinimide form 6.8
PIBSA 1.7
residual reagents (DMAP-propylene oxide etc.) 8.4
PIB 10.2
Other functionalized PIBs 3.4
TEST PROTOCOLS
Protocol 1: Evaluation of the "lacquering" resistance for the deposits of the
5 IDID type
In order to test the performance of these additives according to the invention, the
inventors also developed a new method that is reliable and robust for evaluating
the susceptibility of diesel fuels, in particular those of higher grade, to
lacquering. This method, in contrast to the methods described in the publications
10 cited above, is not a laboratory method but is based on engine tests and is
therefore of technical interest and makes it possible to quantify the effectiveness of
the additives or compositions of additives against lacquering. The method for
measuring lacquering developed by the inventors is detailed below:
- The engine used is a Renault K9K702, four-cylinder 16-valve,
15 high-pressure injection, common rail diesel engine with a cylinder capacity of
1500 cm3 and a power of 65kW: regulation of the fuel injection pressure takes
place in the high-pressure part of the pump.
- The power point is used over a period of 40 h at 4000 rpm; the position of the
injector in the chamber is lowered by 1 mm relative to its nominal position, which
20 on the one hand promotes the release of thermal energy from combustion, and on
the other hand brings the injector closer to the combustion chamber.
- The flow rate of fuel injected is adjusted so as to obtain an exhaust
temperature of 750°C at the start of the test.
49
- The injection advance was increased by 1.5° crankshaft relative to the nominal
setting (increasing from + 12.5° to + 14° crankshaft) always with the aim of
increasing the thermal stresses acting on the injector nozzle.
- Finally, to increase the stresses on the fuel, the injection pressure was
5 increased by 10 MPa relative to the nominal pressure (i.e. increase from 140 MPa
to 150 MPa) and the temperature is set at 65°C at high-pressure pump inlet.
The technology used for the injectors requires a high fuel return, which promotes
degradation of the fuel since it may be subjected to several cycles in the pump and
high-pressure chamber before being injected into the combustion chamber.
10 A variant of the method for testing the clean-up effect (i.e. cleaning of the type 1
and/or type 2 deposits) has also been developed. It is based on the preceding
method but is separated into two parts of 40h and then 30h:
• The first 40 hours are carried out with a higher-grade B7 diesel containing
330 ppm by mass of a detergent of the PIBSI type and 200 ppm by mass of a
15 mixture of fatty acid, predominantly oleic acid with an acid number of 180 mg of
KOH/g, this mixture being known to have a tendency to generate deposits of the
"lacquering" type. After 40h, two of the four injectors are dismantled and assessed
in order to validate the quantity of deposits present and then replaced by two new
injectors.
20 • The last 30 hours of the test are carried out with the product to be
evaluated. At the end of the test (70h in total), the injectors are dismantled and
assessed.
At the end of the test, three batches of two injectors are available:
• Batch 1: 2 injectors after 40h of higher-grade fuel known for its tendency to
25 generate the "lacquering" described above.
• Batch 2: 2 injectors after 40h of higher-grade fuel known for its tendency to
generate the "lacquering" described above + 30h of product to be evaluated.
• Batch 3: 2 injectors after 30h of product to be evaluated.
50
Expression of the results
To ensure that the result is valid, various parameters are monitored during the test:
power, torque and fuel consumption indicate if there is fouling of the injector or if its
operation has deteriorated through formation of deposits since the operating point
5 is the same throughout the test.
The characteristic temperatures of the different fluids (liquid coolant, fuel, oil) allow
the validity of the tests to be monitored. The fuel is set at 65°C at pump inlet, the
liquid coolant is set at 90°C at engine outlet.
10 The smoke values make it possible to monitor combustion timing at the start of the
test (target value of 3FSN) and to ensure that it is properly repeatable from one
test to another.
The injectors are dismantled at the end of the test to examine and assess the
15 deposits formed along the needles. The procedure adopted for assessing the
needles is as follows:
The surface of the needle is divided into 100 points. The deposit of soap (type 1)
and of lacquer (type 2) is assessed for each point. The cylinder zone (directly after
the conical part) represents 68% of the overall score for the needle and the cone
20 zone represents 32% of the overall score for the needle. To facilitate assessment,
each of these two zones is divided into 4. In Figure 4, the percentages shown
correspond to a quarter of the surface of the needles: the overall surface weighting
is therefore 17x4 = 68%.
25 For the soaps (type 1 deposits), the scale of the scores varies from -1 (in the case
of a very fine soap) to -10 (in the case of a very thick, strongly coloured soap). A
value of the effect of the soap is determined by calculating the arithmetic mean of
the scores obtained on the population of points of the needle assessed.
30 For the lacquers (type 2 deposits), the scale of the scores varies from 1 (in the
case of a black lacquer equivalent to significant deposition of lacquer) to 10 (in the
51
case of a very clear lacquer equivalent to a new needle). A value of the effect of
the lacquer is calculated by finding the sum of the number of points belonging to
the score (1 to 10) divided by the value of the score. An overall score (N) out of 10
is then determined by weighting the effect of the lacquers and soaps.
5
Thus, for the properties of maintenance of engine cleanliness ("keep-clean" effect),
a product performance threshold was determined relative to this assessment
procedure: N < 7.5 = Unsatisfactory, N 7.5 = Satisfactory. For the properties of
cleaning the internal parts of the injection system of fouled engines (curative
10 "clean-up" effect), a product performance threshold was determined with respect to
this assessment procedure: A(Nbatch 2_ Nbatch 1)
< 1.55 = Unsatisfactory, A(Nbatch 2_
NGbatch 1) .2. 1.55 = Satisfactory.
Protocol 2: Measurement of loss of power in a diesel engine with a high-
15 pressure injection system (DW10+Zn)
The fuel is tested in a Peugeot DW10 engine using injectors complying with the
Euro 5 standards according to the process CEC F-98-8 DW1OBTED4 developed
and published by the Coordinating European Council (CEC).
20 In order to reproduce the real conditions of a modern diesel engine, a small
quantity of zinc neodecanoate (1 ppm) is added to the test fuel.
This test was developed for distinguishing between fuels based on their capacity
for producing or avoiding external deposits of the injection system relating to
coking or clogging of the injection nozzles (nozzle coking or fouling).
25
This test allows fuels to be differentiated on the basis of the loss of power caused
by the deposits of the coking type (comparison between the percentage loss of
power). This test in particular makes it possible to differentiate a fuel that produces
little deposition of the coking type (loss of power < 2%) from those that produce
30 sufficient coking to cause a loss of power of 2% or more, regarded as
unacceptable for the engine manufacturers.
52
The test according to the protocol CEC F-98-8 DW 10 is summarized below:
Engine Euro 4 Peugeot DW1OBTED4 2.0L, HDi, turbodiesel, 4 cylinders in
line with variable geometry turbocompressor and system for exhaust-gas
recirculation (EGR)
5 Cubic capacity: 1998 cm3
Combustion chamber: 4 valves, direct injection
Power: 100 kW at a speed of 4000 rpm
Torque: 320 N.m at a speed of 2000 rpm
Injection system: Common rail with 6-hole injectors controlled by piezoelectric
10 system (EURO IV)
Max. pressure: 1600 bar
Emission control: Complying with the Euro 4 limits taking into account the
system for post-treatment of the exhaust gases.
The test is divided into the following steps:
15 0- Step of running-in of the injectors: 16 cycles of 1 hour using a non-fouling
reference fuel constituted by a diesel representative of the French market (B7 =
diesel manufactured in France containing 7% of FAME (fatty acid methyl ester) and
complying with EN 590)
The test on the fuel to be evaluated then takes a total of 44 hours, not
20 counting the periods for preparation and cooling. The time of 44 hours is divided
into 32 hours of engine operation and 12 hours with the engine stopped.
1- Engine warm-up step:
1 cycle of 12 minutes under the following conditions:
Step
Time
(min)
Speed (rpm) Torque (Nm)
1 2 Stopped <5
2 3 2000 50
3 4 3500 75
4 3 4000 100
The engine power is then increased up to a maximum load of 4000 rpm for
25 minutes and then the average power is measured for 30s.
53
2- Operation step: 8 cycles of 1 hour as follows:
Step
Time
(min)
Speed
(rpm)
Load
(%)
Torque
(Nm)
Air temperature
after exchanger
(°C)
1 2 1750 20 62 45
2 7 3000 60 173 50
3 2 1750 20 62 45
4 7 3000 80 212 50
5 2 1750 20 62 45
6 10 4000 100 50
7 2 1250 (10) 20 43
8 7 3000 100 50
9 2 1250 (10) 20 43
10 10 2000 100 50
11 2 1250 (10) 20 43
12 7 4000 100 50
. . _ __
rpm Nm in s
and is maintained at this speed for 300s.
5
3- Cooling step: 60 seconds of cooling while stopped followed by 10 seconds while
stopped.
4- Maceration step: engine stopped for 4 hours.
10 The overall cycle 1 to 4 is repeated 4 times. The loss of power is measured in each
operating cycle, i.e. 32 in total.
At the end of the cycle, the engine speed is adjusted to
TEST
Test 1 according to protocol 1: resistance to "lacquering"
15 According to the procedure for evaluating the properties of maintenance of engine
cleanliness (preventive "keep-clean" effect) and cleaning of the internal parts of the
injection system of fouled engines (curative "clean-up" effect), described above
(Protocol 1), performance is evaluated for several compositions of additives
introduced in a diesel matrix representative of the French market (B7 = diesel
20 manufactured in France containing 7% of FAME (fatty acid methyl ester) and
complying with EN 590).
54
The details for each fuel tested, and the results obtained, are shown in Table 4.
Note that tests G, G' and G" correspond to the same test, G corresponding to the
result for the batch of injectors 1, G' corresponding to the result for the batch of
injectors 2 and G" corresponding to the result for the batch of injectors 3. Test G
5
corresponds to the fouling phase ("Dirty-up"), test G' to the cleaning phase ("Cleanup")
and test G" to the phase of maintenance of cleanliness ("keep-clean").
The quantities shown in Table 4 are quantities by mass (mg/kg)
co
C)
C
0
in 0N3-
a
0
0
N
1 0
LO In
N
LO
Oi
Ccoo
d
d-
U)
>,
0- i 0 0
o
N
. In cd
O U) CO a)
0 . I I a a CID
6
•,:r
=
0
B7
Lr)
0 o
I 0
N
o
U0)
1
NI- o
oi
CO
IN:
t.•
u)
0
>.
u)
cu
>.
o
LC) I o
0
N
0
Ln i
N
M
00
7„
k..)
CD i I . . .
-cr
Ls.)
cci
M
I
0
B7
LO
N-...
CT;
r..
N
c;
U) >a),
0 I I 0 C u-)
0)
N''''
6 : ....
(.:..)
i I I a i
N
6)
(.9 Nt:
N
a
B7
I
0
0
N
I I
CO
d-
CT;
C0T)
5.0
U) a>), .
oc
0
0
N cd
I
0)
6)
. i i
O
cs)
cci
e—
=
0
B7
a
a
(-.1
I I .
U)
Lo
oi
03 c,
Ci;
u)
a)
>,
0 LD
0
c)
N
, , , ,
N
L.r)
6
CD I i . I 1 co
6
B7
I I I I I CO
Oi
4,
.
K
Fuel No.
Diesel matrix
3-polyisobutene succinimide-
1,2,4-triazole (ppm)
E
0_
0_
s-
Ill
0L
w
SPE2 (ppm)
QAS (ppm)
N,N-bis(2-ethylhexyl)-1,2,4-
triazole-1-methanamine (ppm)
Overall score (N)
(9-
z
i.9. Z
4.ti
I
"Keep-clean" effect (yes/no)
"Clean-up" effect (yes/no)
56
These tests demonstrate the curative effectiveness (clean-up effect) of the
compositions of additives according to the present invention, i.e. their ability to
remove deposits of the lacquer or soap type already formed on the needles since
the score for the set of injectors G' is greater than that of the batch of injectors G
5 (there was commencement of significant cleaning of the needle), and also confirms
their preventive effectiveness (keep-clean effect) since the score for the set of
injectors G" is greatly increased.
No curative effect (clean-up effect) is observed when fuels 1, 2 or 3 are used.
10 Thus, it is deduced from this that the first, second and third additives used alone in
fuel B7 do not provide a curative effect for said fuel, with respect to deposits of the
soap and/or lacquer type.
However, it is noted that fuel 4 containing a combination of the first, second and
15 third additives has both a preventive (Keep-clean) and curative (Clean-up) effect.
Moreover, it can be seen that comparatively, fuel 5 containing a triazole derivative
not covered by the present invention does not have a significant curative effect
(Clean-up).
20 Test 2 according to protocol 2: resistance to coking
The loss of power is evaluated for several compositions of additives introduced in
the diesel matrix representative of the French market (B7 = diesel manufactured in
France containing 7% of FAME (fatty acid methyl ester) and complying with EN
590), according to protocol 2 (DW10 + Zn) described above. The details of each
25 fuel tested, and the results obtained, are shown in Table 5.
The quantities shown in Table 5 are quantities by mass (mg/kg).
57
Table 5
Fuel No 6 7 8 9 10 11
Diesel matrix B7 B7 B7 B7 B7 B7
3-polyisobutene succinimide-1,2,4-
triazole (ppm)
50 - - - 50 50
SPE2 (ppm) - - - - 200
QAS (ppm) - 50 50 50 50 50
N,N-bis(2-ethylhexyl)-1,2,4-triazole-
1-methanamine (ppm)
- - 5 8 - -
Loss of power (%) -0.1 -6.7 -5.05 -4.51 0.1 0.12
It can be seen that the fuels containing the composition of additives according to
the present invention are particularly remarkable in that they do not generate
5 deposits of the coking type compared with a fuel containing a quaternary
ammonium salt alone (fuel 7) or a combination of a quaternary ammonium salt and
a triazole derivative different from those covered by the present invention (fuels 8
and 9).
10 The specific choice of a triazole derivative according to the invention in
combination with a quaternary ammonium salt and optionally a compound A as
described above (fuels 10 and 11) confers upon the fuel both control of deposits of
the lacquering type (IDID deposit) and/or resistance to deposits of the coking type.
15 The composition of additives according to the present invention is remarkable in
that it makes it possible to obtain fuels having improved performance, in particular
in the case of diesel fuels with a low sulphur content, optionally containing a bio
diesel. The particular combination of additives described above in particular makes
it possible to reduce the fuel consumption of diesel engines, by combining a clean-
20 up effect and. keep-clean effect, minimizing the loss of power and improving the
wear resistance of said fuel.
58
CLAIMS
1. Composition of fuel additives comprising at least:
- a first additive comprising a triazole derivative of the following formula (I):
5
R2
R3
(I)
In which:
10
Ri is selected from the group consisting of a hydrogen atom, a linear or
branched C1 to C8 aliphatic hydrocarbon group, a carboxyl group (—CO2H),
. R2 and R5 are identical or different and represent, independently of one
another, a group selected from the group consisting of a hydrogen atom and
a linear or branched, saturated or unsaturated C1 to C33 aliphatic
15
hydrocarbon group, optionally comprising one or more oxygen atoms in the
form of a carbonyl function (-CO-) and/or carboxyl function (-CO2H), said R2
and R5 groups optionally forming together a ring with 5 to 8 atoms
comprising nitrogen, to which R2 is bound, it being understood that in this
case R2 and R5 then constitute one and the same linear or branched,
20
saturated or unsaturated C1 to C33 aliphatic hydrocarbon group, optionally
substituted with one or more oxygen atoms in the form of a carbonyl function
(-CO-) and/or carboxyl function (-CO2H),
. R3 and R4 are identical or different and represent, independently of one
another, a group selected from the group consisting of a hydrogen atom and
25
a linear or branched, saturated or unsaturated, cyclic or acyclic aliphatic
hydrocarbon group, having from 2 to 200 carbon atoms,
- a second additive comprising a quaternary ammonium salt obtained by ,
reaction of a nitrogen-containing compound comprising a tertiary amine function
with a quaternizing agent, said nitrogen-containing compound being selected
30 from:
(II)
in which R1, R3 and R4 are as defined in one of claims 1 and 3.
59
a) the product of reaction of an acylating agent substituted with a
hydrocarbon group and of a compound comprising at least one tertiary
amine group and a group selected from the primary and secondary amines
and the alcohols,
5
b) a product of the Mannich reaction comprising a tertiary amine group; and
c) amines substituted with a polyalkene group having at least one tertiary
amine group.
2. Composition according to claim 1, characterized in that the mass ratio of the
10 first to the second additive (first : second) is between 1:100 and 100:1,
preferably between 1:10 and 10:1, even more preferably between 1:2 and 2:1.
3. Composition according to one of claims 1 and 2, characterized in that the
triazole derivative has the formula (I) in which R3 and R4 are identical or
15 different and represent, independently of one another, a group selected from
the group consisting of a hydrogen atom and an aliphatic hydrocarbon group
having a number-average molecular weight (Mn) between 200 and 3000.
4. Composition according to any one of claims 1 to 3, characterized in that the
20 triazole derivative is represented by the following formula (II):
5. Composition according to any one of claims 1 to 3, characterized in that the
25 triazole derivative is represented by the following formula (III):
0 R4
o
R3 OH
NH2
R1
N._---,N
H
N
__N
O
(3
0 R4
R3 OH
R1
60
(III)
in which R1, R3 and R4 are as defined in one of claims 1 and 3.
6. Composition according to any one of claims 1 to 3, characterized in that the
5 first additive comprises a mixture of triazole derivatives of formulae (II) and (III)
as defined in claims 4 and 5 respectively.
7. Composition according to any one of claims 1 to 6, characterized in that the
triazole derivative is obtained by reaction of an aminotriazole of the following
10 formula (IV) with a diacid of the following formula (V) and/or a succinic
anhydride of the following formula (VI):
(IV)
15 in which R1, R3 and R4 are as defined in one of claims 1 and 3.
8. Composition according to any one of claims 1 to 7, characterized in that the
quaternizing agent is selected from the group constituted by the dialkyl
sulphates, the carboxylic acid esters, the alkyl halides, the benzyl halides, the
20 hydrocarbon carbonates and the hydrocarbon epoxides optionally mixed with
an acid, alone or in a mixture.
9. Composition according to any one of claims 1 to 8, characterized in that the
nitrogen-containing compound comprises a product of reaction of an acylating
61
agent substituted with a hydrocarbon group and an amine of the following
formula (VII) or (VIII):
R6
R6
N X--NH
/R8
N —X —[0(CH2)min0H
R7
R7
(VII) (VIII)
5
in which:
R6 and R7 are identical or different and represent, independently of one
another, an alkyl group having from 1 to 22 carbon atoms;
X is an alkylene group having from 1 to 20 carbon atoms;
10 m is an integer comprised between 1 and 5;
n is an integer comprised between 0 and 20; and
R8 is a hydrogen atom or an alkyl group having from 1 to 22 carbon atoms.
10.Composition according to any one of claims 1 to 9, characterized in that it
15 further comprises a third additive comprising at least 50% by mass of a
compound A selected from the partial esters of polyols and of saturated or
unsaturated, linear or branched, cyclic or acyclic C4 to C36 monocarboxylic
aliphatic hydrocarbons, said partial esters being able to be used alone or in a
mixture.
20
11.Composition according to claim 10, characterized in that said compound A
comprises x ester unit(s), y hydroxyl unit(s) and z ether unit(s), x, y and z being
integers such that x varies from 1 to 10, y varies from 1 to 10, and z varies
from 0 to 6.
25
12.Composition according to one of claims 10 and• 11, characterized in that the
distribution of ester, hydroxyl and ether units in said compound A is such that x
varies from 1 to 4, y varies from 1 to 7 and z varies from 1 to 3.
62
13.Composition according to any one of claims 10 to 12, characterized in that
compound A is obtained by esterification between:
- one or more C4 to C36 fatty acid(s) optionally comprising one or more
ethylenic bonds; and
5 - a linear or branched, cyclic or acyclic polyol, optionally comprising a
heterocycle with 5 to 6 atoms, preferably a heterocycle with 4 to 5
carbon atoms and one oxygen atom, substituted with hydroxyl groups.
14.Composition according to claim 13, characterized in that the fatty acids are
10 selected from the group constituted by stearic, isostearic, linolenic, oleic,
linoleic, behenic, arachidonic, ricinoleic, palmitic, myristic, lauric, and capric
acids, used alone or in a mixture.
15.Composition according to one of claims 13 and 14, characterized in that the
15 polyol is selected from the polyols comprising more than three hydroxyl
functions and the polyols comprising at least one heterocycle with 5 or 6 atoms,
preferably heterocycles with 4 to 5 carbon atoms and one oxygen atom,
optionally substituted with hydroxyl groups.
20 16. Composition according to any one of claims 13 to 15, characterized in that the
polyol is selected from the polyols comprising at least two heterocycles with 4
or 5 carbon atoms and one oxygen atom, linked by the formation of an acetal
bond between a hydroxyl function of each ring, said heterocycles optionally
being substituted with hydroxyl groups.
25
17.Composition according to any one of claims 10 to 16, characterized in that the
polyol is selected from the group consisting of erythritol, xylitol, arabitol, ribitol,
sorbitol, maltitol, isomaltitol, lactitol, volemitol, mannitol, pentaerythritol, 2-
hydroxymethy1-1,3-propandediol, 1,1,1-tri(hydroxymethyl)ethane,
30 trimethylolpropane, sorbitan and the carbohydrates such as sucrose, fructose,
maltose, glucose and saccharose.
63
18. Composition according to any one of claims 10 to 17, characterized in that
compound A is selected from the sorbitan partial esters, preferably the sorbitan
mono-, di- and triesters, used alone or in a mixture, more preferably the
5 sorbitan partial esters comprising more than 40% by mass of sorbitan triesters.
19.Composition according to any one of claims 10 to 15, characterized in that
compound A is selected from the monoester(s) and/or diester(s) of
polyglycerols having from 2 to 5 glycerol units per molecule.
10
20.Composition according to claim 19, characterized in that compound A is
selected from the monoester(s) and/or diester(s) of polyglycerols derived from
fatty. acid(s), having more than 50% by number of fatty chains comprising
between 12 and 24 carbon atoms.
15
21.Composition according to one of claims 19 and 20, characterized in that
compound A is selected from the diglycerol and/or triglycerol monoester(s)
and/or diester(s).
20 22. Use of a composition of additives as defined in any one of claims 1 to 21, in
a diesel fuel having a sulphur content less than or equal to 500 ppm by mass,
preferably comprising a bio diesel.
23. Diesel fuel having a sulphur content less than or equal to 500 ppm by mass
25 comprising at least 5 ppm by mass of a composition of additives as defined in any
one of claims 1 to 21.
24. Diesel fuel according to claim 23, characterized in that it comprises up to 30%
by volume of bio diesel.
30
25. Fuel according to one of claims 23 and 24, characterized in that it
additionally comprises at least one or more other additives selected from the
64
antioxidants, combustion improvers, corrosion inhibitors, low temperature
performance additives, dyes, demulsifiers, metal deactivators, antifoaming agents,
cetane number improvers, lubricity additives, co-solvents and compatibilizing
agents.
5
26. Fuel according to any one of claims 23 to 25, characterized in that the
concentration by mass of each first and second additive and optionally third
additive varies from 5 to 5000 ppm.
10 27. Use of a diesel fuel as defined in any one of claims 23 to 26, in a diesel
engine, for improving the performance of said engine.
28. Use according to claim 27, for limiting the deposits in said diesel engine.
15 29. Use according to one of claims 27 and 28, characterized in that the engine
is a direct-injection engine, preferably with a high-pressure injection system
("common-rail").
30. Use according to any one of claims 27 to 29, for reducing the fuel
20 consumption of said engine ("Fuel Eco" effect).
31. Use according to any one of claims 27 to 30, for minimizing the loss of
power of said engine.
25 32. Use according to any one of claims 27 to 31, for maintaining the cleanliness
of said engine ("keep-clean" effect) by limiting the deposits of soap and/or lacquer
in the internal components of the injection systems of said engine.
33. Use according to any one of claims 27 to 32, for cleaning the fouled internal
30 parts of the injection system of said engine, by removing, at least partly, the
deposits of soap and/or lacquer in said internal parts (curative "clean-up" effect).