U.S. patent application number 13/991949 was filed with the patent office on 2013-10-31 for additives for fuels and lubricants.
This patent application is currently assigned to INNOSPEC LIMITED. The applicant listed for this patent is Vince Burgess, Anthony Cooney, Alan Ross. Invention is credited to Vince Burgess, Anthony Cooney, Alan Ross.
Application Number | 20130288937 13/991949 |
Document ID | / |
Family ID | 43566926 |
Filed Date | 2013-10-31 |
United States Patent
Application |
20130288937 |
Kind Code |
A1 |
Cooney; Anthony ; et
al. |
October 31, 2013 |
ADDITIVES FOR FUELS AND LUBRICANTS
Abstract
An additive compound comprising a derivative of particular fatty
acids and polyamines has been found to be friction reducing, and
particularly readily miscible in fuels and lubricants. The fatty
acid has more than 12 carbon atoms and at least one carboxylic
group. The polyamine residue has more than two nitrogen atoms. The
mole ratio of the carboxylic groups to nitrogen atoms used to form
the compound is greater than 0.8 carboxylic groups per 1 nitrogen
atom.
Inventors: |
Cooney; Anthony; (Ellesmere
Port, GB) ; Ross; Alan; (Ellesmere Port, GB) ;
Burgess; Vince; (Ellesmere Port, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Cooney; Anthony
Ross; Alan
Burgess; Vince |
Ellesmere Port
Ellesmere Port
Ellesmere Port |
|
GB
GB
GB |
|
|
Assignee: |
INNOSPEC LIMITED
Ellesmere Port, Cheshire
GB
|
Family ID: |
43566926 |
Appl. No.: |
13/991949 |
Filed: |
December 8, 2011 |
PCT Filed: |
December 8, 2011 |
PCT NO: |
PCT/GB2011/052438 |
371 Date: |
June 21, 2013 |
Current U.S.
Class: |
508/449 ; 44/306;
44/385; 44/386; 44/387; 508/513; 554/104 |
Current CPC
Class: |
C10M 2215/08 20130101;
C10N 2030/70 20200501; C10N 2040/25 20130101; C10L 1/221 20130101;
C10M 133/04 20130101; C10N 2030/06 20130101; C10L 1/224 20130101;
C10L 1/2222 20130101; C10M 2215/04 20130101; C10M 2207/18 20130101;
C10L 10/08 20130101; C10M 133/02 20130101; C10N 2040/255 20200501;
C10N 2040/252 20200501; C10M 133/06 20130101; C10M 133/16 20130101;
C10M 2207/18 20130101; C10M 2215/04 20130101 |
Class at
Publication: |
508/449 ; 44/385;
44/387; 44/306; 44/386; 508/513; 554/104 |
International
Class: |
C10L 10/08 20060101
C10L010/08; C10M 133/02 20060101 C10M133/02 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 9, 2010 |
GB |
1020891.6 |
Claims
1. A method of reducing friction in an engine, by adding an
additive compound to a fuel and/or lubricant which is employed by
the engine, the additive compound comprising: (1) a fatty acid
residue having more than 12 carbon atoms and at least one
carboxylic group; and (2) a polyamine residue having more than two
nitrogen atoms; wherein the mole ratio of the carboxylic groups to
nitrogen atoms used to form the compound is greater than 0.8
carboxylic groups per 1 nitrogen atom.
2. The method as claimed in claim 1, wherein the additive compound
is a fatty acid amide or a salt of a fatty acid and a polyamine, or
a mixture thereof.
3. The method as claimed in claim 1, wherein the fatty acid is
represented by the formula: R(COOH).sub.n wherein n is 1, 2, 3 or
4, and R represents a hydrocarbyl group having at least (13 minus
n) carbon atoms.
4. The method as claimed in claim 3 wherein the fatty acid is a
monocarboxylic acid having from 8 to 30 carbon atoms.
5. The method as claimed in claim 4 wherein the fatty acid is
selected from tall oil fatty acid, oleic acid and isostearic
acid.
6. The method as claimed in claim 1, wherein the polyamine is an
aliphatic polyamine having a hydrocarbyl group of 4 to 50 carbon
atoms.
7. The method as claimed in claim 1, wherein the additive compound
is selected from the group consisting of: the reaction product of a
monocarboxylic acid having more than 12 carbon atoms and at least
one carboxylic group, and diethylene triamine, in a molar ratio
(expressed as the reactant compounds) of at least 2.5 to 1; the
reaction product of a monocarboxylic acid having more than 12
carbon atoms and at least one carboxylic group, and triethylene
tetramine, in a molar ratio (expressed as the reactant compounds)
of at least 3.5 to 1; and the reaction product of a monocarboxylic
acid having more than 12 carbon atoms and at least one carboxylic
group, and tetraethylene pentamine, in a molar ratio (expressed as
the reactant compounds) of at least 4.5 to 1.
8-11. (canceled)
12. A compound which comprises: (1) a fatty acid residue having
more than 12 carbon atoms and at least one carboxylic group; and
(2) a polyamine residue having more than two nitrogen atoms;
wherein the mole ratio of the carboxylic groups to nitrogen atoms
used to form the compound is greater than 0.8 carboxylic groups per
1 nitrogen atom.
13. A method of preparing a compound as claimed in claim 12,
comprising reacting: (1) a fatty acid having more than 12 carbon
atoms and at least one carboxylic group, and (2) a polyamine having
more than two nitrogen atoms; at a mole ratio of greater than 0.8
carboxylic groups per 1 nitrogen atom.
14. A fuel composition comprising a fuel and a compound as claimed
in claim 12.
15. An additive composition containing a solvent and a compound as
claimed in claim 12, the additive composition being adapted for
addition into a fuel, with dilution therein of said compound.
16. A method of increasing the efficiency of an engine utilising a
fuel and/or lubricant, by adding an additive compound to the fuel
and/or lubricant which is employed by the engine, the additive
compound comprising: (1) a fatty acid residue having more than 12
carbon atoms and at least one carboxylic group; and (2) a polyamine
residue having more than two nitrogen atoms; wherein the mole ratio
of the carboxylic groups to nitrogen atoms used to form the
compound is greater than 0.8 carboxylic groups per 1 nitrogen
atom.
17. A method of improving the friction performance of an engine
lubricant, by adding an additive compound to the lubricant which is
employed by the engine, the additive compound comprising: (1) a
fatty acid residue having more than 12 carbon atoms and at least
one carboxylic group; and (2) a polyamine residue having more than
two nitrogen atoms; wherein the mole ratio of the carboxylic groups
to nitrogen atoms used to form the compound is greater than 0.8
carboxylic groups per 1 nitrogen atom.
18. The method as claimed in claim 6, wherein the aliphatic
polyamine has a hydrocarbyl group of 4 to 20 carbon atoms.
19. The method as claimed in claim 7, wherein the monocarboxylic
acid is TOFA.
Description
[0001] The present invention relates to additives for fuels and
lubricants, to improvements in stability of additives in fuels and
lubricants, and to improvements in the operation of internal
combustion engines.
[0002] Over the years the price of fuel has undergone fluctuations,
but the trend has been for it to become more expensive. This is to
be expected fundamentally because of limitations in the supply, but
also because of the taxation policy of Governments. The trend is
expected to continue.
[0003] The present invention is concerned with additives which
enable internal combustion engines to use fuel more efficiently;
that is, with additives which increase the useful energy derived
from an internal combustion engine and reduce the non-useful, or
"lost", energy.
[0004] There is a vast body of published information, patents and
literature, concerning fuels and lubricants, and friction reducing
additives for lubricants and for fuels. However there is no causal
relationship between the addition of an additive to a fuel or
lubricant, and the achievement of higher efficiency or greater
useful output. For example a lubricating additive for a fuel may be
added in order to achieve lubrication, and hence maintain good
operation, of a fuel pump, and not be directly associated with
improvement in useful output.
[0005] A very widely used test to assess the lubricity of a fuel is
the HFRR test. In the HFRR a wear scar is produced by a ball moved
in reciprocation over the surface of an object, both immersed in a
sample fuel. The size of the wear scar is taken as a measure of
lubricity, and the test is very apt for situations in which one
surface bears under load on another, and the aim is to assess
wear.
[0006] The sliding of a plurality of pistons within their
corresponding cylinders gives rise to a substantial energy loss
when operating an engine.
[0007] Another test is the TE77 reciprocating sliding wear test.
From measurements taken using a high frequency reciprocating
tribometer, the percentage change in Coefficient of Friction (.mu.)
due to the presence of a friction modifier additive can be
calculated.
[0008] In an article entitled "Simulated fuel dilution and
friction-modifier effects on piston ring friction" by 0. Smith et
al, published in Proceedings of the Institution of Mechanical
Engineers, Part J: Journal of Engineering Tribology, Mechanical
Engineering Publications, vol. 220, no. 3, pp. 181-189, published
on 1 Jan. 2006, the authors describe how 40-60% of mechanical
friction can be attributed to the piston/ring/cylinder wall
interface. The authors go on to describe how much of this is a
result of the compression ring whose lubrication is kept purposely
minimal to control exhaust emissions. A series of tests using a
TE-77 reciprocating tribometer was used to investigate the friction
coefficient reduction effects of fatty acids on a base oil.
Implicit in this teaching is the idea that the fuel and the
lubricant are not isolated from one another; there is a feed of
fuel into the lubricant, particularly in the cylinder liner oil
film. The authors postulate that the fuel may be used to administer
friction modifier additives directly to the top ring zone of the
engine where its effects are most beneficial.
[0009] It is an object of the present invention primarily to
achieve improved performance of friction reducing additives in
fuels and/or lubricants.
[0010] It is a further object of the present invention to provide
friction reducing additives which have excellent compatibility
(including miscibility) in fuels and/or lubricants.
[0011] In accordance with a first aspect of the present invention
there is provided a method of reducing friction in an engine, by
use of an additive compound present in the fuel and/or lubricant
which is employed, the additive compound comprising:
(1) a fatty acid residue having more than 12 carbon atoms and at
least one carboxylic group; and (2) a polyamine residue having more
than two nitrogen atoms; wherein the mole ratio of the carboxylic
groups to nitrogen atoms used to form the compound is greater than
0.8 carboxylic groups per 1 nitrogen atom.
[0012] In accordance with the method we have found that certain
additives gave excellent results in reducing friction, as revealed
by slide tests which reflected the sliding action of a piston
within a cylinder. We found also that a sub-group of such additives
also had particularly high levels of compatibility (which may be
expressed as stability and/or miscibility) in fuels or lubricants.
As noted in the 0. Smith et al article referenced above, even when
additives are dosed into fuels there is likely to be carry over
into the lubricant region of an engine, particularly in the upper
cylinder area. This may be regarded as something the lubricant must
be able to cope with, without instability or immiscibility arising;
or it may be regarded as something the formulator may exploit; for
example by using the fuel to deliver a friction-reducing additive
which may act locally, for example in the cylinder liner oil film,
or elsewhere in the lubricant in the cylinders, or in the bulk
lubricant; or in more than one such location. Any such approach
represents a preferred feature of the present invention.
[0013] The improvement may be as defined in the second aspect,
below.
[0014] The improvement may be as defined in the third aspect,
below.
[0015] The improvement may be as defined in the fourth aspect,
below.
[0016] In accordance with a second aspect of the present invention
there is provided the use of an additive compound in a fuel and/or
lubricant for the purpose of increasing the efficiency of an engine
utilising said fuel and/or lubricant, wherein the additive compound
comprises:
(1) a fatty acid residue having more than 12 carbon atoms and at
least one carboxylic group; and (2) a polyamine residue having more
than two nitrogen atoms; wherein the mole ratio of the carboxylic
groups to nitrogen atoms used to form the compound is greater than
0.8 carboxylic groups per 1 nitrogen atoms.
[0017] In accordance with a third aspect of the present invention
there is provided the use of an additive compound in a fuel and/or
lubricant for the purpose of reducing friction in an engine
utilising said fuel and/or lubricant, wherein the additive compound
comprises:
(1) a fatty acid residue having more than 12 carbon atoms and at
least one carboxylic group; and (2) a polyamine residue having more
than two nitrogen atoms; wherein the mole ratio of the carboxylic
groups to nitrogen atoms used to form the compound is greater than
0.8 carboxylic groups per 1 nitrogen atoms.
[0018] In accordance with a fourth aspect of the present invention
there is provided the use of an additive compound in a fuel, for
the purpose of improving the friction performance of an engine
lubricant, wherein the additive compound comprises:
(1) a fatty acid residue having more than 12 carbon atoms and at
least one carboxylic group; and (2) a polyamine residue having more
than two nitrogen atoms; wherein the mole ratio of the carboxylic
groups to nitrogen atoms used to form the compound is greater than
0.8 carboxylic groups per 1 nitrogen atom.
[0019] The lubricant may be improved adjacent to the piston rings,
where the concentration of the transferred additive may be high;
and/or it may be improved by dispersion of said additive into the
bulk fuel. In either such case excellent miscibility is
required.
[0020] Equally, excellent miscibility is required in the fuel in
which the additive was delivered, in this aspect.
[0021] In accordance with a fifth aspect of the present invention
there is provided the use of fatty acid-polyamine derivative in a
fuel and/or lubricant for a first purpose of reducing friction in
an engine, and for a second purpose of achieving stability of the
derivative in the fuel and/or lubricant, wherein the derivative
comprises:
(1) a fatty acid residue having more than 12 carbon atoms and at
least one carboxylic group; and (2) a polyamine residue having more
than two nitrogen atoms; wherein the mole ratio of the carboxylic
groups to nitrogen atoms used to form the compound is greater than
0.8 carboxylic groups per 1 nitrogen atom.
[0022] The improvement described in the first to fifth aspects may
suitably be improvement indicated by HFRR testing, as described
herein; for example, for diesel, with reference to standard test
method IP 450: "Diesel fuel--Assessment of lubricity using the
high-frequency reciprocating rig (HFRR)", or for gasoline, using
the modified HFRR method described in the examples in this
specification.
[0023] The improvement described in the first to fifth aspects may
suitably be improvement indicated by TE77 testing, as described
herein.
[0024] Reducing friction in an engine in this specification is
preferably reducing friction in cylinders of the engine.
[0025] The improvement described in the first to fifth aspects may
suitably be improvement indicated by testing for compatibility as
between the additive compound (i.e. the acid-amine derivative) and
the fuel and/or lubricant, as described herein; preferably to
assess miscibility therebetween, on mixing at ambient
temperature.
[0026] The additive compound could be supplied in a solvent, used
to deliver the additive compound into a fuel and/or lubricant.
[0027] Preferably, in accordance with this invention, an additive
compound is added to a fuel and/or lubricant directly or via a said
solvent. The additive compound may be added into a lubricant by
direct addition thereto or from a fuel, by passing piston rings, in
use. Thus, compatibility in all such liquids is sought.
[0028] The following statements of preferred features of the
present invention apply to any of the first, second, third, fourth
and fifth aspects, and to the fifth, sixth, seventh, eighth and
ninth aspects set forth later.
[0029] A derivative of a fatty acid and a polyamine useful in the
present invention may be a fatty acid amide. Some unreacted fatty
acid and/or unreacted polyamine may be present, though it is
preferred that at least one of the acid and nitrogen functions
undergo substantially complete reaction; and preferably both do,
when they are present as molar equivalents (by functional
groups).
[0030] A derivative of a fatty acid and a polyamine useful in the
present invention may be a salt of a fatty acid and a polyamine.
Some unreacted fatty acid and/or unreacted polyamine may be
present, though it is preferred that both the acid and nitrogen
functions undergo substantially complete reaction; and preferably
both do, when they are present as molar equivalents (by functional
groups).
[0031] A derivative used in the present invention may comprise a
fatty acid amide and a salt of a fatty acid and a polyamine. This
may be produced by admixture but is preferably produced by a
reaction between a fatty acid and a polyamine, which yields a mixed
reaction product. Some unreacted fatty acid and/or unreacted
polyamine may be present, though it is preferred that both the acid
and nitrogen functions undergo substantially completely reaction;
and preferably both do, when they are present as molar equivalents
(by functional groups).
[0032] In this specification when we talk about the amount or ratio
of this additive we mean, when there is more than one of the said
compounds, the summated amount. In particular, carboxylic acids,
such as TOFA, are usually blends of homologous compounds.
[0033] In this specification when we talk about the number of
carbon atoms, nitrogen atoms or carboxylic acid groups we are
referring, as is conventional, to the mean number of such atoms or
groups, per molecule.
[0034] In a fatty acid having a stated number of carbon atoms and
at least one carboxylic group, the carbon atom(s) present in the
carboxylic group(s) are included in that stated number.
[0035] Thus, the incorporation of the defined fatty acid-polyamine
derivative into fuel can provide wear benefits--for example
improving the sliding action of the pistons in their cylinders and
thereby improve the fuel economy--whilst providing a high degree of
assurance that the additive compound will remain solvated in the
fuel; preferably also a high degree of assurance that the additive
compound will remain solvated in the solvent (e.g. hydrocarbon)
used for an additive composition; and preferably also a high degree
of assurance that the additive compound will remain solvated in an
engine lubricant hydrocarbon, when passage past the piston rings of
an engine occurs.
[0036] Preferably the carboxylic groups referred to herein are
carboxylic acid groups --COOH before reaction.
[0037] Preferably, the fatty acid is represented by the
formula:
R(COOH).sub.n
wherein R represents a hydrocarbyl group having at least (13 minus
n) carbon atoms, preferably at least (15 minus n) carbon atoms.
[0038] Suitably n may be 1, 2, 3 or 4, more preferably 1 or 2.
[0039] When n is 1 (one), as is most preferred, R is preferably a
hydrocarbyl group having at least 12 carbon atoms, preferably at
least 14 carbon atoms.
[0040] Preferably R is a hydrocarbyl group having up to 50 carbon
atoms, preferably up to 32 carbon atoms, most preferably up to 24
carbon atoms.
[0041] R may include aromatic and heterocyclic groups. The
preferred hydrocarbyl groups are aliphatic groups such as an alkyl
group and an alkenyl group, which may have a straight chain or a
branched chain, of suitable length to meet the definition given
herein. Examples of preferred fatty acids are aliphatic acids
having 12 to 30 carbon atoms, preferably 14 to 30 carbon atoms, and
include myristic acid, stearic acid, isostearic acid, arachic acid,
behenic acid, lignoceric acid, cerotic acid, montanic acid,
melissic acid, palmitic acid, oleic acid, eraidic acid, linolic
acid, linoleic acid, fatty acid of coconut oil, fatty acid of
hardened fish oil, fatty acid of hardened rapeseed oil, fatty acid
of hardened tallow oil, soy fatty acid, and fatty acid of hardened
palm oil. The examples further include dodecenyl succinic acid and
its anhydride.
[0042] Most preferably, the fatty acid is a monocarboxylic acid (n
is 1), whose group R has from 12 to 30 carbon atoms; for example
oleic acid, isostearic acid, stearic acid or tall oil fatty
acid.
[0043] Preferred fatty acids are those derived from vegetable oils
and animal oils and fats.
[0044] In some preferred embodiments, mixtures of fatty acids are
preferred; for example mixtures of fatty acids derived from
vegetable oils and animal oils and fats.
[0045] Preferably nitrogen atoms in the polyamine are present as
amine groups, suitably unsubstituted amine groups.
[0046] Primary, secondary or tertiary amine groups may be present
in the polyamine, as appropriate. Preferably --NH.sub.2 groups are
present at the termini of molecules and --NH-- groups at
intermediate positions of the molecules.
[0047] The nitrogen atoms referred to in the definitions and claims
of this invention are of groups which can react with the carboxylic
groups.
[0048] A salt of a fatty acid and a polyamine may be obtained by
mixing a said acid and the amine, for example at a temperature of
20 to 100.degree. C.
[0049] A fatty acid amide may be prepared by a
dehydration-condensation reaction between a said fatty acid and a
polyamine, for example at a temperature of 20 to 200.degree. C.
under atmospheric or reduced pressure.
[0050] Preferred features of a polyamine which can be used for the
formation of a salt or an amide are as follows.
[0051] Preferably the polyamine is an aliphatic polyamine, suitably
having a hydrocarbyl group(s) of 4 to 50 carbon atoms, preferably 4
to 20 carbon atoms.
[0052] Preferably the polyamine has 3 to 10 nitrogen atoms,
preferably 3 to 6 nitrogen atoms. Especially preferred polyamines
include diethylene triamine (DETA), triethylene tetramine (TETA),
tetraethylene pentamine (TEPA), and pentaethylene hexamine
(PEHA).
[0053] Preferably the mole ratio of the carboxylic groups to
nitrogen atoms used to form the derivative in the invention is at
least 0.9 carboxylic groups per 1 nitrogen atom, more. Preferably
at least 0.95 carboxylic groups per 1 nitrogen atom, and most
preferably at least 0.98 carboxylic groups per 1 nitrogen atom.
[0054] Preferably the mole ratio of the carboxylic groups to
nitrogen atoms used to form the derivative in the invention is up
to 3 carboxylic groups per 1 nitrogen atom, more preferably up to 2
carboxylic groups per 1 nitrogen atom, and preferably up to 1.5
carboxylic groups per 1 nitrogen atom. More preferably the mole
ratio of the carboxylic groups to nitrogen atoms used to form the
derivative in the invention is up to 1.2 carboxylic groups per 1
amino group, more preferably up to 1.1 carboxylic groups per 1
amino group, and most preferably at least 1.02 carboxylic groups
per 1 nitrogen atom.
[0055] One preferred embodiment uses a reaction product of a
monocarboxylic acid as defined herein, preferably selected from
TOFA, oleic acid and isostearic acid (preferably TOFA) and
diethylene triamine, in a molar ratio (expressed as the reactant
compounds rather that as reactive groups) of at least 2.5 to 1,
preferably at least 2.8 to 1, more preferably at least 2.95 to 1,
acid to amine. Suitably the molar ratio (also expressed in such
terms) is up to 6 to 1, preferably up to 4 to 1, preferably up to
3.5 to 1, preferably up to 3.2 to 1, more preferably up to 3.05 to
1, acid to amine.
[0056] One preferred embodiment uses a reaction product of a
monocarboxylic acid as defined herein, preferably selected from
TOFA, oleic acid and isostearic acid (preferably TOFA) and
triethylene tetramine, in a molar ratio (expressed as the reactant
compounds rather that as reactive groups) of at least 3.5 to 1,
preferably at least 3.8 to 1, more preferably at least 3.95 to 1,
acid to amine. Suitably the molar ratio (also expressed in such
terms) is up to 7 to 1, preferably up to 5 to 1, preferably up to
4.5 to 1, preferably up to 4.2 to 1, more preferably up to 4.05 to
1, acid to polyamine compound.
[0057] One preferred embodiment uses a reaction product of a
monocarboxylic acid as defined herein, preferably selected from
TOFA, oleic acid and isostearic acid (preferably TOFA) and
tetraethylene pentamine, in a molar ratio (expressed as the
reactant compounds rather that as reactive groups) of at least 4.5
to 1, preferably at least 4.8 to 1, more preferably at least 4.95
to 1, acid to amine. Suitably the molar ratio (also expressed in
such terms) is up to 8 to 1, preferably up to 6 to 1, preferably up
to 5.5 to 1, preferably up to 5.2 to 1, more preferably up to 5.05
to 1, acid to polyamine compound.
[0058] Preferred aspects of the present invention do not employ a
salt of (1) a molybdenum oxide, sulfide or oxysulfide and (2) an
amide reaction product of a carboxylic acid component and a
polyamine component wherein the charge mass ratio (CMR) of the
carboxylic acid component to the polyamine component is about 2:1
to 1:1.
[0059] Especially preferred aspects of the present invention do not
employ any molybdenum compound.
[0060] The derivative of a fatty acid and a polyamine, namely a
fatty acid amide or a salt of a fatty acid and a polyamine; or any
mixture thereof, are incorporated into the selected fuel, as an
additive; or into a solvent, to form an additive composition which
can be added to a fuel and/or lubricant. Two or more such additives
can be added to a fuel, lubricant or solvent separately or in
admixture. The additive can be previously diluted with a small
amount of a diluent oil such as kerosene or an aromatic solvent to
give a concentrated additive solution and the concentrated additive
solution can be incorporated into the fuel to be treated. For
instance, an additive of the invention can be mixed with a diluent
to give a concentrated additive solution containing 1 to 70 weight
percent of the additive, and the thus obtained concentrated
solution can then be diluted with the fuel and/or lubricant to be
treated.
[0061] Commercial fuels may include a number of additives which
perform a variety of different functions. Depending on the fuel,
additives may be used to improve engine performance, fuel handling,
fuel stability and contaminant control. Typical additives include
antioxidants to prevent oxidation and thus gum forming reactions;
stability improvers to prevent sediment formation; metal
deactivators to chelate to metal ions and prevent the catalysis
thereby of oxidation reactions; cetane improvers to promote
oxidation at higher temperatures by the generation of free
radicals; octane improvers which prevent pre-ignition or knock in
spark ignition engines; dispersants or detergents to prevent
deposit formation in the injection system or remove existing
deposits; valve seat recession additives; further lubricity
improvers if wished, particularly to prevent wear; as well as
corrosion inhibitors, anti-static additives, dehazers and
demulsifiers, cold-flow improvers, anti-icing additives; pour-point
improvers, CFPP improvers, wax anti-settling additives, anti-foams,
dyes, markers, odour masks and drag reducers. For reasons of
convenience and accurate dosing these are preferably provided in an
additive composition with a fatty acid amide or fatty acid amine
salt but could if wished be added separately.
[0062] There are no specific limitations with respect to the fuel
for which the invention is employable. The fuel may, for example,
be diesel, gasoline, with or without oxygenates, including ethers
and alcohols; or may itself be an alcohol, for example methanol or
ethanol. Suitably the fuel is any fuel which may be used in
compression ignition engines and spark ignition engines.
[0063] A gasoline fuel which may be used in the present invention
is a liquid fuel for use with spark ignition engines (typically or
preferably containing primarily or only C4-C12 hydrocarbons) and
satisfying international gasoline specifications, such as ASTM
D-439 and EN228. The term includes blends of distillate hydrocarbon
fuels with oxygenated components such as ethanol, as well as the
distillate fuels themselves.
[0064] A diesel fuel which may be used in the present invention may
comprise a petroleum-based fuel oil, especially a middle distillate
fuel oil. Such distillate fuel oils generally boil within the range
of from 110.degree. C. to 500.degree. C., e.g. 150.degree. C. to
400.degree. C. The diesel fuel may comprise atmospheric distillate
or vacuum distillate, cracked gas oil, or a blend in any proportion
of straight run and refinery streams such as thermally and/or
catalytically cracked and hydro-cracked distillates.
[0065] A diesel fuel which may be used in the present invention may
comprise non-renewable Fischer-Tropsch fuels such as those
described as GTL (gas-to-liquid) fuels, CTL (coal-to-liquid) fuels
and OTL (oil sands-to-liquid).
[0066] A diesel fuel which may be used in the present invention may
comprise a renewable fuel such as a biofuel or biodiesel.
[0067] A diesel fuel which may be used in the present invention may
comprise 1st generation biodiesel. First generation biodiesel
contains esters of, for example, vegetable oils, animal fats and
used cooking fats. This form of biodiesel may be obtained by
transesterification of oils, for example rapeseed oil, soybean oil,
safflower oil, palm 25 oil, corn oil, peanut oil, cotton seed oil,
tallow, coconut oil, physic nut oil (Jatropha), sunflower seed oil,
used cooking oils, hydrogenated vegetable oils or any mixture
thereof, with an alcohol, usually a monoalcohol, in the presence of
a catalyst.
[0068] A diesel fuel which may be used in the present invention may
comprise second generation biodiesel. Second generation biodiesel
is derived from renewable resources such as vegetable oils and
animal fats and processed, often in the refinery, often using
hydroprocessing such as the H-Bio process developed by Petrobras.
Second generation biodiesel may be similar in properties and
quality to petroleum based fuel oil streams, for example renewable
diesel produced from vegetable oils, animal fats etc. and marketed
by ConocoPhillips as Renewable Diesel and by Neste as NExBTL.
[0069] A diesel fuel which may be used in the present invention may
comprise third generation biodiesel. Third generation biodiesel
utilises gasification and Fischer-Tropsch technology including
those described as BTL (biomass-to-liquid) fuels. Third generation
biodiesel does not differ widely from some second generation
biodiesel, but aims to exploit the whole plant (biomass) and
thereby widens the feedstock base. A diesel fuel which may be used
in the present invention may contain blends of any or all of the
above diesel fuels.
[0070] In some embodiments a diesel fuel which may be used in the
present invention may be a blended diesel fuel comprising
bio-diesel. In such blends the bio-diesel may be present in an
amount of, for example up to 0.5%, up to 1%, up to 2%, up to 3%, up
to 4%, up to 5%, up to 10%, up to 20%, up to 30%, up to 40%, up to
50%, up to 60%, up to 70%, up to 80%, up to 90%, up to 95% or up to
99%.
[0071] In some embodiments a diesel fuel which may be used in the
present invention may comprise a secondary fuel, for example
ethanol and/or an alcohol and/or ether as an oxygenate. Preferably
however the diesel fuel does not contain ethanol.
[0072] Preferably, a diesel fuel which may be used in the present
invention has a sulphur content of at most 0.05% by weight, more
preferably of at most 0.035% by weight, especially of at most
0.015%. Fuels with even lower levels of sulphur are also suitable
such as, fuels with less than 50 ppm sulphur by weight, preferably
less than 20 ppm, for example 10 ppm or less.
[0073] Examples of diesel fuels to which the invention is
applicable are diesel fuels which have been treated to reduce the
sulphur content to have the above content. Preferred diesel fuels
are those which are as defined in BS EN 590 or ASTM D975
[0074] A suitable lubricant may be a mineral base oil and/or a
synthesized base oil that are commonly used in lubricants.
[0075] The mineral base oil may be, for example, a lubricant base
oil prepared by atmospheric distilling crude oil, further
distilling the atmospheric residue under reduced pressure, and
refining the resulting lubricant fraction by at least one of
solvent deasphalting, solvent extraction, hydrocracking, solvent
dewaxing, and hydrorefining; or a wax-isomerized mineral oil or a
lubricant base oil prepared by isomerization of GTL WAX
(gas-to-liquid wax).
[0076] The sulphur content of the mineral base oil is usually not
higher than 1% wt/wt, preferably not higher than 0.2% wt/wt, more
preferably not higher than 0.1% wt/wt, still more preferably not
higher than 0.005% wt/wt.
[0077] Examples of the synthetic base oil may include polybutene or
hydrides thereof; poly-alpha-olefins, such as 1-octene oligomer or
1-decene oligomer, or hydrides thereof; diesters, such as
ditridecyl glutarate, di-2-ethylhexyl adipate, diisodecyl adipate,
ditridecyl adipate, or di-2-ethylhexyl sebacate; polyol esters,
such as neopentyl glycol esters, trimethylolpropane caprylate,
trimethylolpropane pelargonate, pentaerythritol-2-ethylhexanoate,
or pentaerythritol pelargonate; aromatic synthetic oils, such as
alkylnaphthalene, alkylbenzene, or aromatic esters; and mixtures of
two or more of these.
[0078] A lubricant used in the present invention may be the
above-mentioned mineral base oil, above-mentioned synthetic base
oil, or a mixture of two or more oils selected from these. For
example, one or more mineral base oils, one or more synthetic base
oils, or a mixed oil of one or more mineral base oils and one or
more synthetic oils, may be used.
[0079] A lubricant used in the present invention may include one or
more lubricant additives, in addition to the carboxylic-polyamine
compound of the present invention, Further lubricant additives may
for example be selected from antioxidants, detergents, anti-wear
agents, metal deactivators, rust inhibitors, friction modifiers,
anti-foam agents, viscosity index improvers, and
demulsifying/emulsifying agents.
[0080] In addition to the additive mentioned above, which is a
derivative of a fatty acid and a polyamine, the invention may
employ one or more additional friction modifiers, that is, one or
more additional friction modifiers which are not derivatives of
fatty acids and polyamines. Such additional friction modifiers are
called hereinafter AFMs for brevity and clarity.
[0081] AFMs known in the art include the following: [0082] Fatty
acids, for example aliphatic fatty acids having 12 to 30 carbon
atoms, preferably 14 to 30 carbon atoms; especially such fatty
acids which are named above [0083] Esters of fatty acids [0084]
Aliphatic amines [0085] Aliphatic esters [0086] Aromatic esters
[0087] Aliphatic ethers [0088] Polyethers [0089] Polyetheramines
[0090] Polyhydric aliphatic alcohols [0091] Hydrocarbyl succinic
acids and derivatives [0092] Reaction products of acylating agents
and amines, for example poly(isobutenylsuccinimides) (PIBSIs)
[0093] N,N-bis(hydroxyalkyl)-alkylamine [0094] Hydroxyl containing
esters of mono carboxylic acid and polyols [0095] Alkylalkoxy
amides [0096] Polyalkylene amines [0097] Mannich bases based on
tertiary alky substituted phenol and C1-20 primary amines or
polyalkylene amines [0098] Polyisobutylene amines [0099] Mixtures
of esters (e.g. as defined herein) and polyisobutylene amines
[0100] Mixtures of esters (e.g. as defined herein) and
polyetheramines.
[0101] Examples of sources of information about AFMs which are
believed to be of use in the present invention are as follows. Any
of these may be regarded as a preferred feature of the present
invention and so may be claimed, in conjunction with any of the
first, second and third aspects given above. The patent
specifications mentioned may be consulted if more information is
required.
[0102] U.S. Pat. No. 4,396,517: the AFMs in this disclosure of
interest in the present invention are Mannich bases based on C4-20
tertiary alkyl substituted phenol, aldehyde and C1-20 primary
amines. An example includes the di(mono-cocoamine) mannich base of
p-tert-butylphenol, paraformaldehyde and cocoamine. [0103] the
phenol may suitably be of the formula
##STR00001##
[0103] wherein R is preferably hydrogen, but can be a C1 to C30
hydrocarbyl group, which may be an alkyl, alkenyl, aryl, alkaryl or
aralkyl group and R.sup.1 is preferably a tertiary hydrocarbyl
group, preferably alkyl or alkenyl containing 4 to 20 carbon atoms.
Representative phenols that may be used are p-tert-butylphenols,
p-tert-octylphenol, p-tert-dodecyl-phenol, p-tert-hexadecylphenol.
[0104] the aldehyde contemplated may be an aliphatic aldehydes,
typified by formaldehyde or paraformaldehyde, acetaldehyde, and
aldol (beta-hydroxy butyraldehyde); aromatic aldehydes, such as
benzaldehyde and heterocyclic aldehydes, such as furfural. The
aldehyde may contain a substituent group such as hydroxyl, halogen,
nitro and the like. In short, any substituent can be used which
does not take a major part in the reaction. Preference, however, is
given to the aliphatic aldehydes, formaldehyde being particularly
preferred. [0105] the amine may contain a primary amino group.
Preferably, these include saturated and unsaturated aliphatic
amines containing 1 to 20 carbon atoms, for example
polyalkylenepolyamines of the formula
NH.sub.n(R.sup.2NH).sub.nH.
[0106] U.S. Pat. No. 4,427,562: the AFMs in this disclosure of
interest in the present invention are N-alkoxyalkyl amides
represented by the following formula:
##STR00002##
wherein R is a hydrocarbyl group or a mixture of hydrocarbyl groups
containing from about 5-30 carbon atoms; R.sup.1 is a hydrocarbyl
group containing from about 2-10 carbon atoms; and R.sup.2 is
hydrogen. The N-alkoxyalkyl amides may be formed by the reaction of
primary alkoxyalkylamines with carboxylic acids such as formic
acid, or alternatively by ammonolysis of the appropriate formate
ester.
[0107] U.S. Pat. No. 4,617,026: the AFMs in this disclosure of
interest in the present invention are hydroxyl-containing esters of
a monocarboxylic acid and a glycol or trihydric alcohol, said ester
additive having at least one free hydroxyl group. More
particularly, the AFM may be an ester of a monocarboxylic acid and
a glycol or trihydric alcohol, said acid having about 12 to about
30 carbon atoms, said glycol being an alkane diol or oxa-alkane
diol wherein said alkane is a straight chain hydrocarbon of about 2
to about 5 carbon atoms and said trihydric alcohol has a straight
chain hydrocarbon structure of about 3 to about 6 carbon atoms,
said ester additive having at least one free hydroxyl group.
Examples include glycerol monooleate and glycerol dioleate.
[0108] WO9835000: the AFMs in this disclosure of interest in the
present invention are C7+ primary, linear alcohols, preferably
C12-C24. The alcohol may be added in an amount of at least about
0.05 to 0.5 wt % fuel.
[0109] U.S. Pat. No. 6,203,584: the AFMs in this disclosure of
interest in the present invention are (1) a fuel-soluble aliphatic
hydrocarbyl-substituted amine having at least one basic nitrogen
atom where the hydrocarbyl group has a number average molecular
weight of about 700 to 3,000, and (2) a poly(oxyalkylene) amine
having at least one basic nitrogen atom and a sufficient number of
oxyalkylene units to render the poly(oxyalkylene) amine soluble in
hydrocarbons boiling in the gasoline range; and (b) an ester of a
carboxylic acid and a polyhydric alcohol, wherein the carboxylic
acid has from one to about four carboxylic acid groups and from
about 8 to about 50 carbon atoms and the polyhydric alcohol has
from about 2 to about 50 carbon atoms and from about 2 to about 6
hydroxy groups.
[0110] Examples comprise combinations of pibamine or polyetheramine
with glycerol monooleate or pentaerythritol mono oleate
[0111] WO 01/72930: the AFMs in this disclosure of interest in the
present invention are the reaction products of a natural or
synthetic oil, for example a C6-C22 fatty acid ester, for example
an oil is selected from the group consisting of beef tallow oil,
lard oil, palm oil, castor oil, cottonseed oil, corn oil, peanut
oil, soybean oil, sunflower oil, olive oil, whale oil, menhaden
oil, sardine oil, coconut oil, palm kernel oil, babassu oil, rape
oil and soya oil: and at least one alkanolamine preferably selected
from the group consisting of monoethanolamine, diethanolamine,
propanolamine, isopropanolamine, dipropanolamine,
di-isopropanolamine, butanolamines, aminoethylaminoethanol and
mixtures thereof. For example the reaction product of coconut oil
and diethanolamine.
[0112] US2004/0154218: the AFMs in this disclosure of interest in
the present invention include polyalkylene oxides, preferably
derived from an alkylene oxide wherein the alkylene group has from
about 2 to 5 carbon atoms. Preferably, the polyalkylene-oxide is an
oligomer or polymer of an alkylene oxide selected from the group
consisting of ethylene oxide, propylene oxide, butylene oxide, and
pentylene oxide. Ethylene oxide and propylene oxide are
particularly preferred. In addition, mixtures of alkylene oxides
are desirable in which, for example, a mixture of ethylene oxide
and propylene oxide may be used. A respective molar ratio of from
about 1:5 to 5:1 may be used in the case of a mixture of ethylene
oxide and propylene oxide. The polyalkylene-oxide may also be
end-capped with an ether or ester function to give, for example, a
mono-alkoxy polyalkylene-oxide, such as n-butoxy polypropylene
glycol. A desirable number of moles of the polyalkylene-oxide will
be in the range of from about 3 to 50 moles of alkylene oxide per 1
mole of hydrocarbyl amide. More preferably, the range of from about
3 to 20 moles is particularly desirable. Most preferably, the range
of from about 4 to 15 moles is most preferable.
[0113] EP0020037: the AFMs in this disclosure of interest in the
present invention are oil-soluble aliphatic hydrocarbyl-substituted
succinimide or succinamide materials, wherein the hydrocarbyl group
contains about 12 to 36 carbon atoms and is preferably derived from
an isomerized straight chain alpha-olefin.
[0114] Alternatively: we may define suitable and related AFMs as
being the reaction product of a carboxylic acid-derived acylating
agent and an amine; for example PIBSA, suitably having a
hydrocarbyl substituent with a number average molecular weight (Mn)
of between 250 to 1500, a polyalkylene polyamine, preferably with 1
to 6 carbon atoms and preferably with 2 to 8 nitrogen atoms, for
example ethylenediamine, diethylenetriamine, triethylenetetramine,
tetraethylenepentamine, tri(tri-methylene)tetramine,
pentaethylenehexamine, aminoethylethanolamine,
hexaethyleneheptamine or 1,2-propylenediamine. Preferably the molar
ratio of acylating agent:amino compound is preferably from 2:1 to
1:1.
[0115] Alternatively: a number of suitable acylated,
nitrogen-containing compounds having a hydrocarbyl substituent of
at least 8 carbon atoms and made by reacting a carboxylic acid
acylating agent with an amino compound are known to those skilled
in the art. In such compositions the acylating agent is linked to
the amino compound through an imido, amido, amidine or acyloxy
ammonium linkage. The hydrocarbyl substituent of at least 8 carbon
atoms may be in either the carboxylic acid acylating agent derived
portion of the molecule or in the amino compound derived portion of
the molecule, or both. Preferably, however, it is in the acylating
agent portion. The acylating agent can vary from formic acid and
its acylating derivatives to acylating agents having high molecular
weight aliphatic substituents of up to 5,000, 10,000 or 20,000
carbon atoms. The amino compounds can vary from ammonia itself to
amines typically having aliphatic substituents of up to about 30
carbon atoms, and up to 11 nitrogen atoms.
[0116] A preferred class of acylated amino compounds suitable for
use in the present invention are those formed by the reaction of an
acylating agent having a hydrocarbyl substituent of at least 8
carbon atoms and a compound comprising at least one primary or
secondary amine group. The acylating agent may be a mono- or
polycarboxylic acid (or reactive equivalent thereof) for example a
substituted succinic, phthalic or propionic acid and the amino
compound may be a polyamine or a mixture of polyamines, for example
a mixture of ethylene polyamines. Alternatively the amine may be a
hydroxyalkyl-substituted polyamine. The hydrocarbyl substituent in
such acylating agents preferably comprises at least 10, more
preferably at least 12, for example 30 or 50 carbon atoms. It may
comprise up to about 200 carbon atoms. Preferably the hydrocarbyl
substituent of the acylating agent has a number average molecular
weight (Mn) of from 160 to 5000, preferably from 170 to 2800, for
example from 250 to 1500, preferably from 500 to 1500 and more
preferably 500 to 1100. An Mn of 700 to 1300 is especially
preferred. In a particularly preferred embodiment, the hydrocarbyl
substituent has a number average molecular weight of 700-1000.
[0117] Illustrative of hydrocarbyl substituent based groups
containing at least eight carbon atoms are n-octyl, n-decyl,
n-dodecyl, tetrapropenyl, n-octadecyl, oleyl, chloroctadecyl,
triicontanyl, etc. The hydrocarbyl based substituents may be made
from homo- or interpolymers (e.g. copolymers, terpolymers) of mono-
and di-olefins having 2 to 10 carbon atoms, for example ethylene,
propylene, butane-1, isobutene, butadiene, isoprene, 1-hexene,
1-octene, etc. Preferably these olefins are 1-monoolefins. The
hydrocarbyl substituent may also be derived from the halogenated
(e.g. chlorinated or brominated) analogs of such homo- or
interpolymers. Alternatively the substituent may be made from other
sources, for example monomeric high molecular weight alkenes (e.g.
1-tetra-contene) and chlorinated analogs and hydrochlorinated
analogs thereof, aliphatic petroleum fractions, for example
paraffin waxes and cracked and chlorinated analogs and
hydrochlorinated analogs thereof, white oils, synthetic alkenes for
example produced by the Ziegler-Natta process (e.g. poly(ethylene)
greases) and other sources known to those skilled in the art. Any
unsaturation in the substituent may if desired be reduced or
eliminated by hydrogenation according to procedures known in the
art.
[0118] The term "hydrocarbyl" as used within this specification
denotes a group having a carbon atom directly attached to the
remainder of the molecule and having a predominantly aliphatic
hydrocarbon character. Suitable hydrocarbyl based groups may
contain non-hydrocarbon moieties. For example they may contain up
to one non-hydrocarbyl group for every ten carbon atoms provided
this non-hydrocarbyl group does not significantly alter the
predominantly hydrocarbon character of the group. Those skilled in
the art will be aware of such groups, which include for example
hydroxyl, halo (especially chloro and fluoro), alkoxyl, alkyl
mercapto, alkyl sulphoxy, etc. Preferred hydrocarbyl based
substituents are purely aliphatic hydrocarbon in character and do
not contain such groups.
[0119] The hydrocarbyl-based substituents are preferably
predominantly saturated, that is, they contain no more than one
carbon-to-carbon unsaturated bond for every ten carbon-to-carbon
single bonds present. Most preferably they contain no more than one
carbon-to-carbon non-aromatic unsaturated bond for every 50
carbon-to-carbon bonds present.
[0120] Preferred hydrocarbyl-based substituents are
poly-(isobutene)s known in the art.
[0121] Conventional polyisobutenes and so-called "highly-reactive"
polyisobutenes are suitable for use in the invention. Highly
reactive polyisobutenes in this context are defined as
polyisobutenes wherein at least 50%, preferably 70% or more, of the
terminal olefinic double bonds are of the vinylidene type as
described in EP0565285. Particularly preferred polyisobutenes are
those having more than 80 mol % and up to 100 mol % of terminal
vinylidene groups such as those described in EP1344785.
[0122] Amino compounds useful for reaction with these acylating
agents include the following:
(1) polyalkylene polyamines of the general formula:
(R.sup.3).sub.2N[U--N(R.sup.3)].sub.nR.sup.3
wherein each R.sup.3 is independently selected from a hydrogen
atom, a hydrocarbyl group or a hydroxy-substituted hydrocarbyl
group containing up to about 30 carbon atoms, with proviso that at
least one R.sup.3 is a hydrogen atom, n is a whole number from 1 to
10 and U is a C1-18 alkylene group. Preferably each R.sup.3 is
independently selected from hydrogen, methyl, ethyl, propyl,
isopropyl, butyl and isomers thereof. Most preferably each R.sup.3
is ethyl or hydrogen. U is preferably a C1-4 alkylene group, most
preferably ethylene.
[0123] Specific examples of polyalkylene polyamines (1) include
ethylenediamine, diethylenetriamine, triethylenetetramine,
tetraethylenepentamine, tri(tri-methylene)tetramine,
pentaethylenehexamine, hexaethylene-heptamine,
1,2-propylenediamine, and other commercially available materials
which comprise complex mixtures of polyamines. For example, higher
ethylene polyamines optionally containing all or some of the above
in addition to higher boiling fractions containing 8 or more
nitrogen atoms etc.
[0124] Specific examples of polyalkylene polyamines (1) which are
hydroxyalkyl-substituted polyamines include
N-(2-hydroxyethyl)ethylene diamine, N,N'-bis(2-hydroxyethyl)
ethylene diamine, N-(3-hydroxybutyl) tetramethylene diamine,
etc.
(2) heterocyclic-substituted polyamines including
hydroxyalkyl-substituted polyamines wherein the polyamines are as
described above and the heterocyclic substituent is selected from
nitrogen-containing aliphatic and aromatic heterocycles, for
example piperazines, imidazolines, pyrimidines, morpholines,
etc.
[0125] Specific examples of the heterocyclic-substituted polyamines
(2) are N-2-aminoethyl piperazine, N-2 and N-3 amino propyl
morpholine, N-3(dimethyl amino) propyl piperazine,
2-heptyl-3-(2-aminopropyl) imidazoline, 1,4-bis(2-aminoethyl)
piperazine, 1-(2-hydroxy ethyl) piperazine, and
2-heptadecyl-1-(2-hydroxyethyl)-imidazoline, etc.
(3) aromatic polyamines of the general formula:
Ar(NR.sup.3.sub.2).sub.y
wherein Ar is an aromatic nucleus of 6 to 20 carbon atoms, each
R.sup.3 is as defined above and y is from 2 to 8.
[0126] Specific examples of the aromatic polyamines (3) are the
various isomeric phenylene diamines, the various isomeric
naphthalene diamines, etc.
4) The amine reactant may alternatively be a compound of general
formula R.sup.2R.sup.3NH where each of R.sup.2 and R.sup.3
independent represents a hydrocarbyl group (as defined herein),
preferably a hydrocarbon group (as defined herein), or a hydrogen
atom.
[0127] Preferably at least one of R.sup.2 and R.sup.3 represents a
hydrocarbyl group.
[0128] Preferably both R.sup.2 and R.sup.3 represent a hydrocarbyl
group.
[0129] Suitable terminal groups of a hydrocarbyl group R.sup.2
and/or R.sup.3 may include --CH.sub.3, .dbd.CH.sub.2, --OH,
--C(O)OH and derivatives thereof. Suitable derivatives include
esters and ethers. Preferably a hydrocarbyl group R.sup.2 and/or
R.sup.3 does not contain a terminal amine.
[0130] A preferred hydrocarbyl group for each of R.sup.2 and
R.sup.3 is a group of the formula
--[R.sup.4NH].sub.pR.sup.5X
wherein R.sup.4 is an alkylene group having from 1 to 10 carbons,
preferably from 1 to 5, preferably 1 to 3 carbons, preferably 2
carbons; wherein R.sup.5 is an alkylene group having from 1 to 10
carbons, preferably from 1 to 5, preferably 1 to 3 carbons,
preferably 2 carbons; wherein p is an integer from 0 to 10; wherein
X is selected from --CH.sub.3, --CH.sub.2.dbd.CH.sub.2, --OH, and
--C(O)OH.
[0131] A preferred hydrocarbyl group for each of R.sup.2 and
R.sup.3 is a group of the formula
--[(CH.sub.2).sub.qNH].sub.p(CH.sub.2).sub.rX
wherein p is an integer from 0 to 10, preferably 1 to 10,
preferably from 1 to 5, preferably from 1 to 3, preferably 1 or 2;
wherein q is an integer from 1 to 10, preferably 1 to 10,
preferably from 1 to 5, preferably from 1 to 3, preferably 1 or 2;
wherein r is an integer from 1 to 10, preferably 1 to 10,
preferably from 1 to 5, preferably from 1 to 3, preferably 1 or 2;
and wherein X is selected from --CH.sub.3, --CH.sub.2.dbd.CH.sub.2,
--OH, and --C(O)OH.
[0132] Preferably X is --CH.sub.3, or --OH.
[0133] Further amines which may be used in this invention include
compounds derived from amines selected from ammonia, butylamine,
aminoethylethanolamine, aminopropan-2-ol, 5-aminopentan-1-ol,
2-(2-aminoethoxy)ethanol, monoethanolamine, 3-aminopropan-1-ol,
2-((3-aminopropyl)amino)ethanol, dimethylaminopropylamine, and
N-(alkoxyalkyl)-alkanediamines including
N-(octyloxyethyl)-1,2-diaminoethane and
N-(decyloxypropyl)-N-methyl-1,3-diaminopropane.
[0134] Specific examples of amines which may be used in this
invention and having a tertiary amino group can include but are not
limited to: N,N-dimethyl-aminopropylamine,
N,N-diethyl-aminopropylamine, N,N-dimethyl-amino ethylamine. The
nitrogen or oxygen containing compounds capable of condensing with
the acylating agent and further having a tertiary amino group can
further include amino alkyl substituted heterocyclic compounds such
as 1-(3-aminopropyl)imidazole and 4-(3-aminopropyl)morpholine,
1-(2-aminoethyl)piperidine, 3,3-diamino-N-methyldi-propylamine, and
3'3-aminobis(N,N-dimethylpropylamine). Other types of compounds
capable of condensing with the acylating agent and having a
tertiary amino group include alkanolamines including but not
limited to triethanolamine, trimethanolamine,
N,N-dimethylaminopropanol, N,N-diethylaminopropanol,
N,N-diethylaminobutanol, N,N,N-tris(hydroxyethyl)amine and
N,N,N-tris(hydroxymethyl)amine.
[0135] Many patents have described useful acylated nitrogen
compounds including U.S. Pat. Nos. 3,172,892; 3,219,666; 3,272,746;
3,310,492; 3,341,542; 3,444,170; 3,455,831; 3,455,832; 3,576,743;
3,630,904; 3,632,511; 3,804,763, 4,234,435 and U.S. Pat. No.
6,821,307. A preferred acylated nitrogen-containing compound of
this class is that made by reacting a poly(isobutene)-substituted
succinic acid-derived acylating agent (e.g., anhydride, acid,
ester, etc.) wherein the poly(isobutene) substituent has between
about 12 to about 200 carbon atoms and the acylating agent has from
1 to 5, preferably from 1 to 3, preferably 1 or 2, succinic-derived
acylating groups; with a mixture of ethylene polyamines having 3 to
about 9 amino nitrogen atoms, preferably about 3 to about 8
nitrogen atoms, per ethylene polyamine and about 1 to about 8
ethylene groups. These acylated nitrogen compounds are formed by
the reaction of a molar ratio of acylating agent:amino compound of
from 10:1 to 1:10, preferably from 5:1 to 1:5, more preferably from
2:1 to 1:2 and most preferably from 2:1 to 1:1. In especially
preferred embodiments, the acylated nitrogen compounds are formed
by the reaction of acylating agent to amino compound in a molar
ratio of from 1.8:1 to 1:1.2, preferably from 1.6:1 to 1:1.2, more
preferably from 1.4:1 to 1:1.1 and most preferably from 1.2:1 to
1:1. This type of acylated amino compound and the preparation
thereof is well known to those skilled in the art and are described
in the above-referenced US patents.
[0136] Another type of acylated nitrogen compound belonging to this
class is that made by reacting the afore-described alkylene amines
with the afore-described substituted succinic acids or anhydrides
and aliphatic mono-carboxylic acids having from 2 to about 22
carbon atoms. In these types of acylated nitrogen compounds, the
mole ratio of succinic acid to mono-carboxylic acid ranges from
about 1:0.1 to about 1:1. Typical of the monocarboxylic acid are
formic acid, acetic acid, dodecanoic acid, butanoic acid, oleic
acid, stearic acid, the commercial mixture of stearic acid isomers
known as isostearic acid, tolyl acid, etc. Such materials are more
fully described in U.S. Pat. Nos. 3,216,936 and 3,250,715.
[0137] A further type of acylated nitrogen compound suitable for
use in the present invention is the product of the reaction of a
fatty monocarboxylic acid of about 12-30 carbon atoms and the
afore-described alkylene amines, typically, ethylene, propylene or
trimethylene polyamines containing 2 to 8 amino groups and mixtures
thereof. The fatty mono-carboxylic acids are generally mixtures of
straight and branched chain fatty carboxylic acids containing 12-30
carbon atoms. Fatty dicarboxylic acids could also be used. A widely
used type of acylated nitrogen compound is made by reacting the
afore-described alkylene polyamines with a mixture of fatty acids
having from 5 to about 30 mole percent straight chain acid and
about 70 to about 95 percent mole branched chain fatty acids. Among
the commercially available mixtures are those known widely in the
trade as isostearic acid. These mixtures are produced as a
by-product from the dimerization of unsaturated fatty acids as
described in U.S. Pat. Nos. 2,812,342 and 3,260,671.
[0138] The branched chain fatty acids can also include those in
which the branch may not be alkyl in nature, for example phenyl and
cyclohexyl stearic acid and the chloro-stearic acids. Branched
chain fatty carboxylic acid/alkylene polyamine products have been
described extensively in the art. See for example, U.S. Pat. Nos.
3,110,673; 3,251,853; 3,326,801; 3,337,459; 3,405,064; 3,429,674;
3,468,639; 3,857,791. These patents are referenced for their
disclosure of fatty acid/polyamine condensates for their use in
lubricating oil formulations.
[0139] Suitably the molar ratio of the acylating group of an
acylating agent defined above and the reacting amine group of said
amine is in the range 0.5-5:1, preferably 0.8-2.2:1. At a ratio of
1:1 the reaction product is called mono-PIBSI, and at a ratio of
2:1 it is called bis-PIBSI and requires a polyamine as
reactant.
[0140] US2005/223630: the AFMS in this disclosure of interest in
the present invention are the reaction products of a carboxylic
acid-derived acylating agent and an amine; for example a
polyisobutenyl succinimide.
[0141] An alternative or additional AFM of interest in the present
invention may additionally comprise additional components selected
from: [0142] a) carrier oils comprising an optionally esterified
polyether, [0143] b) polyetheramines, [0144] c)
hydrocarbyl-substituted amines wherein the hydrocarbyl substituent
is substantially aliphatic and contains at least 8 carbon atoms,
[0145] d) nitrogen-containing condensates of a phenol, aldehyde and
primary or secondary amine, [0146] e) aromatic esters of a
polyalkylphenoxyalkanol.
[0147] Compounds a) to e) may be described further as follows:
a) Carrier Oil
[0148] A carrier oil may have any suitable molecular weight. A
preferred molecular weight is in the range 500 to 5000.
[0149] In a preferred aspect the polyether carrier oil is a mono
end-capped polypropylene glycol. Preferably the end cap is a group
consisting of or containing a hydrocarbyl group having up to 30
carbon atoms. More preferably the end cap is or comprises an alkyl
group having from 4 to 20 carbon atoms or from 12 to 18 carbon
atoms.
[0150] The alkyl group may be branched or straight chain.
Preferably it is a straight chain group.
[0151] Further hydrocarbyl end capping groups include
alkyl-substituted phenyl, especially where the alkyl substituent(s)
is or are alkyl groups of 4 to 20 carbon atoms, preferably 8 to 12,
preferably straight chain.
[0152] The hydrocarbyl end capping group may be attached to the
polyether via a linker group. Suitable end cap linker groups
include an ether oxygen atom (--O--), an amine group (--NH--), an
amide group (--CONH--), or a carbonyl group --(C.dbd.O)--.
[0153] In a preferred embodiment the carrier oil is a
polypropyleneglycol monoether of the formula:
##STR00003##
where R.sup.6 is straight chain C.sub.1-C.sub.30 alkyl, preferably
C.sub.4-C.sub.20 alkyl, preferably C.sub.12-C.sub.18 alkyl; and n
is an integer of from 10 to 50, preferably 10 to 30, more
preferably 12 to 20.
[0154] Such alkyl polypropyleneglycol monoethers are obtainable by
the polymerisation of propylene oxide using an aliphatic alcohol,
preferably a straight chain primary alcohol of to 20 carbon atoms,
as an initiator. If desired a proportion of the propyleneoxy units
may be replaced by units derived from other C.sub.2-C.sub.6
alkylene oxides, e.g. ethylene oxide or isobutylene oxide, and are
to be included within the term "polypropyleneglycol". The initiator
may also be a phenol or alkyl phenol of the formula R.sup.7OH, a
hydrocarbyl amine or amide of the formula R.sup.7NH.sub.2 or
R.sup.7CONH, respectively, where R.sup.7 is C.sub.1-C.sub.30
hydrocarbyl group, preferably a saturated aliphatic or aromatic
hydrocarbyl group such as alkyl, phenyl or phenalkyl etc. Preferred
initiators include long chain alkanols giving rise to the long
chain polypropyleneglycol monoalkyl ethers.
[0155] In a further aspect the polypropyleneglycol may be an ester
(R.sup.6COO) group where R.sup.6 is defined above. In this aspect
the carrier oil may be a polypropyleneglycol monoester of the
formula
##STR00004##
where R.sup.6 and n are as defined above and R.sup.8 is a
C.sub.1-C.sub.30 hydrocarbyl group, preferably an aliphatic
hydrocarbyl group, and more preferably C.sub.1-C.sub.10 alkyl.
b) Polyetheramines
[0156] Suitable hydrocarbyl-substituted polyoxyalkylene amines or
polyetheramines are described in the literature (for example U.S.
Pat. No. 6,217,624 and U.S. Pat. No. 4,288,612) and have the
general formula:
##STR00005##
or a fuel-soluble salt thereof; wherein R is a hydrocarbyl group
having from about 1 to about 30 carbon atoms; R1 and R2 are each
independently hydrogen or lower alkyl having from about 1 to about
6 carbon atoms and each R1 and R2 is independently selected in each
--O--CHR1-CHR2- unit; A is amino, N-alkyl amino having about 1 to
about 20 carbon atoms in the alkyl group, N,N-dialkyl amino having
about 1 to about 20 carbon atoms in each alkyl group, or a
polyamine moiety having about 2 to about 12 amine nitrogen atoms
and about 2 to about 40 carbon atoms; x is an integer from about 5
to about 100; and y is 0 or 1. In the formula, above, R is suitably
a hydrocarbyl group having from about 1 to about 30 carbon atoms.
Preferably, R is an alkyl or alkylphenyl group. More preferably, R
is an alkylphenyl group, wherein the alkyl moiety is a straight or
branched chain alkyl of from about 1 to about 24 carbon atoms.
[0157] Preferably, one of R1 and R2 is lower alkyl of 1 to 4 carbon
atoms, and the other is hydrogen. More preferably, one of R1 and R2
is methyl or ethyl, and the other is hydrogen.
[0158] In general, A is amino, N-alkyl amino having from about 1 to
about 20 carbon atoms in the alkyl group, preferably about 1 to
about 6 carbon atoms, more preferably about 1 to about 4 carbon
atoms; N,N-dialkyl amino having from about 1 to about 20 carbon
atoms in each alkyl group, preferably about 1 to about 6 carbon
atoms, more preferably about 1 to about 4 carbon atoms; or a
polyamine moiety having from about 2 to about 12 amine nitrogen
atoms and from about 2 to about 40 carbon atoms, preferably about 2
to 12 amine nitrogen atoms and about 2 to 24 carbon atoms. More
preferably, A is amino or a polyamine moiety derived from a
polyalkylene polyamine, including alkylene diamine. Most
preferably, A is amino or a polyamine moiety derived from ethylene
diamine or diethylene triamine.
[0159] Preferably, x is an integer from about 5 to about 50, more
preferably from about 8 to about 30, and most preferably from about
10 to about 25.
[0160] The polyetheramines will generally have a molecular weight
in the range from about 600 to about 10,000.
[0161] Fuel-soluble salts of the compounds of formula I can be
readily prepared for those compounds containing an amino or
substituted amino group and such salts are contemplated to be
useful for preventing or controlling engine deposits. Suitable
salts include, for example, those obtained by protonating the amino
moiety with a strong organic acid, such as an alkyl- or
arylsulfonic acid. Preferred salts are derived from toluenesulfonic
acid and methanesulfonic acid.
[0162] Other suitable polyetheramines are those taught in U.S. Pat.
No. 5,089,029 and U.S. Pat. No. 5,112,364.
c) Hydrocarbyl-Substituted Amines
[0163] Hydrocarbyl-substituted amines suitable for use in the
present invention are well known to those skilled in the art and
are described in a number of patents. Among these are U.S. Pat.
Nos. 3,275,554; 3,438,757; 3,454,555; 3,565,804; 3,755,433 and
3,822,209. These patents describe suitable hydrocarbyl amines for
use in the present invention including their method of
preparation.
d) Nitrogen-Containing Condensates of Phenols, Aldehydes, and Amino
Compounds
[0164] Phenol/aldehyde/amine condensates useful as AFMs in the
present invention include those generically referred to as Mannich
condensates. Such compounds can be made by reacting simultaneously
or sequentially at least one active hydrogen compound for example a
hydrocarbon-substituted phenol (e.g., an alkyl phenol wherein the
alkyl group has at least an average of about 8 to 200; preferably
at least 12 up to about 200 carbon atoms), having at least one
hydrogen atom bonded to an aromatic carbon, with at least one
aldehyde or aldehyde-producing material (typically formaldehyde or
a precursor thereof) and at least one amino or polyamino compound
having at least one NH group. The amino compounds include primary
or secondary monoamines having hydrocarbon substituents of 1 to 30
carbon atoms or hydroxyl-substituted hydrocarbon substituents of 1
to about 30 carbon atoms. Another type of typical amino compound
are the polyamines described above in relation to acylated
nitrogen-containing compounds.
[0165] One class of preferred nitrogen containing detergent for use
as an AFM in the present invention are those formed by a Mannich
reaction between:
(a) an aldehyde; (b) a polyamine; and (c) an optionally substituted
phenol.
[0166] Any aldehyde may be used as aldehyde component (a) but
preferred are aliphatic aldehydes. Preferably the aldehyde has 1 to
10 carbon atoms, preferably 1 to 6 carbon atoms, more preferably 1
to 3 carbon atoms. Most preferably the aldehyde is
formaldehyde.
[0167] Polyamine component (b) may be selected from any compound
including two or more amine groups. Preferably the polyamine is a
polyalkylene polyamine. Suitable polyalkylene polyamines are as
previously defined herein.
[0168] Preferably the polyamine has 1 to 15 nitrogen atoms,
preferably 1 to 10 nitrogen atoms, more preferably 3 to 8 nitrogen
atoms.
[0169] Preferably the polyamine is selected from ethylenediamine,
diethylenetriamine, triethylenetetramine, tetraethylenepentamine,
pentaethylenehexamine, hexaethyleneheptamine, and
heptaethyleneoctamine. Most preferably it is tetraethylenepentamine
or ethylene diamine.
[0170] Commercially available sources of polyamines typically
contain mixtures of isomers and/or oligomers, and products prepared
from these commercially available mixtures fall within the scope of
the present invention.
[0171] Optionally substituted phenol component (c) may be
substituted with 0 to 4 groups on the aromatic ring (in addition to
the phenol OH). For example it may be a tri- or di-substituted
phenol. Most preferably component (c) is a mono-substituted phenol.
Substitution may be at the ortho, and/or meta, and/or para
position(s).
[0172] Preferably the phenol component (c) carries one or more
optionally substituted alkyl substituents. Preferably the component
(c) is a monoalkyl phenol, especially a para-substituted monoalkyl
phenol.
[0173] In some preferred embodiments component (c) comprises an
alkyl substituted phenol in which the phenol carries one or more
alkyl chains having a total of less than 28 carbon atoms,
preferably less than 24 carbon atoms, preferably less than 20
carbon atoms, more preferably less than 18 carbon atoms, preferably
less than 16 carbon atoms and most preferably less than 14 carbon
atoms.
[0174] For example component (c) may have alkyl substituents having
from 4 to 20 carbons atoms, preferably 6 to 18, more preferably 8
to 16, especially 10 to 14 carbon atoms. In some particularly
preferred embodiments, component (c) is a phenol having a C12 alkyl
substituent.
[0175] In other preferred embodiments component (c) is substituted
with a larger alkyl chain, for example those having in excess of 20
carbon atoms. Particularly preferred compounds are those in which
the phenol is substituted with a hydrocarbyl residue made from homo
or interpolymers (e.g. copolymers, terpolymers) of mono- and
di-olefins having 2 to 10 carbon atoms, for example ethylene,
propylene, butane-1, isobutene, butadiene, isoprene, 1-hexene,
1-octene, etc. Preferably these olefins are 1-monoolefins. The
hydrocarbyl substituent may also be derived from the halogenated
(e.g. chlorinated or brominated) analogs of such homo- or
interpolymers. Alternatively the substituent may be made from other
sources which are well known to those skilled in the art.
[0176] Especially preferred are phenols substituted with a
polyisobutene residue of molecular weight of between 250 and 5000,
for example between 500 and 1500, preferably between 650 and 1200,
most preferably between 700 and 1000.
[0177] Suitable compounds include the reaction product obtained by
reacting components (a), (b) and (c) in a ratio of from 5:1:5 to
0.1:1:0.1, more preferably from 3:1:3 to 0.5:1:0.5.
[0178] Components (a) and (b) are preferably reacted in a ratio of
from 4:1 to 1:1 (aldehyde:polyamine), preferably from 2:1 to 1:1.
Components (a) and (c) are preferably reacted in a ratio of from
4:1 to 1:1 (aldehyde:phenol), more preferably from 2:1 to 1:1.
[0179] Especially preferred compounds d) are those formed by
reacting components (a), (b) and (c) in a ratio of 1:1:1 or 2:1:2.
Mixtures of these compounds may also be used. Typically component
(b) comprises a mixture of isomers and/or oligomers. Component (c)
may also comprise a mixture of isomers and/or homologues.
e) Aromatic Esters of a Polyalkylphenoxyalkanol
[0180] The aromatic ester component which may be employed additive
composition is an aromatic ester of a polyalkylphenoxyalkanol and
has the following general formula:
##STR00006##
or a fuel-soluble salt thereof wherein R is hydroxy, nitro or
--(CH2)x-NR5R6, wherein R5 and R6 are independently hydrogen or
lower alkyl having 1 to 6 carbon atoms and x is 0 or 1; R1 is
hydrogen, hydroxy, nitro or --NR7R8 wherein R7 and R8 are
independently hydrogen or lower alkyl having 1 to 6 carbon atoms;
R2 and R3 are independently hydrogen or lower alkyl having 1 to 6
carbon atoms; and R4 is a polyalkyl group having an average
molecular weight in the range of about 450 to 5,000.
[0181] The preferred aromatic ester compounds employed in the
present invention are those wherein R is nitro, amino,
N-alkylamino, or --CH2NH2 (aminomethyl). More preferably, R is a
nitro, amino or --CH2NH2 group. Most preferably, R is an amino or
--CH2NH2 group, especially amino. Preferably, R1 is hydrogen,
hydroxy, nitro or amino. More preferably, R1 is hydrogen or
hydroxy. Most preferably, R1 is hydrogen. Preferably, R4 is a
polyalkyl group having an average molecular weight in the range of
about 500 to 3,000, more preferably about 700 to 3,000, and most
preferably about 900 to 2,500. Preferably, the compound has a
combination of preferred substituents.
[0182] Preferably, one of R2 and R3 is hydrogen or lower alkyl of 1
to 4 carbon atoms, and the other is hydrogen. More preferably, one
of R2 and R3 is hydrogen, methyl or ethyl, and the other is
hydrogen. Most preferably, R2 is hydrogen, methyl or ethyl, and R3
is hydrogen.
[0183] When R and/or R1 is an N-alkylamino group, the alkyl group
of the N-alkylamino moiety preferably contains 1 to 4 carbon atoms.
More preferably, the N-alkylamino is N-methylamino or
N-ethylamino.
[0184] Similarly, when R and/or R1 is an NN-dialkylamino group,
each alkyl group of the N,N-dialkylamino moiety preferably contains
1 to 4 carbon atoms. More preferably, each alkyl group is either
methyl or ethyl. For example, particularly preferred
N,N-dialkylamino groups are N,N-dimethylamino,
N-ethyl-N-methylamino and N,N-diethylamino groups.
[0185] A further preferred group of compounds are those wherein R
is amino, nitro, or --CH2NH2 and R1 is hydrogen or hydroxy. A
particularly preferred group of compounds are those wherein R is
amino, R1, R2 and R3 are hydrogen, and R4 is a polyalkyl group
derived from polyisobutene.
[0186] It is preferred that the R substituent is located at the
meta or, more preferably, the para position of the benzoic acid
moiety, i.e., para or meta relative to the carbonyloxy group. When
R1 is a substituent other than hydrogen, it is particularly
preferred that this R1 group be in a meta or para position relative
to the carbonyloxy group and in an ortho position relative to the R
substituent. Further, in general, when R1 is other than hydrogen,
it is preferred that one of R or R1 is located para to the
carbonyloxy group and the other is located meta to the carbonyloxy
group. Similarly, it is preferred that the R4 substituent on the
other phenyl ring is located para or meta, more preferably para,
relative to the ether linking group.
[0187] The aromatic esters e) will generally have a molecular
weight in the range from about 700 to about 3,500, preferably from
about 700 to about 2,500.
[0188] Fuel-soluble salts of the compounds e) can be readily
prepared for those compounds containing an amino or substituted
amino group and such salts are contemplated to be useful for
preventing or controlling engine deposits. Suitable salts include,
for example, those obtained by protonating the amino moiety with a
strong organic acid, such as an alkyl- or arylsulfonic acid.
Preferred salts are derived from toluenesulfonic acid and
methanesulfonic acid.
[0189] When the R or R1 substituent is a hydroxy group, suitable
salts can be obtained by deprotonation of the hydroxy group with a
base. Such salts include salts of alkali metals, alkaline earth
metals, ammonium and substituted ammonium salts. Preferred salts of
hydroxy-substituted compounds include alkali metal, alkaline earth
metal and substituted ammonium salts.
[0190] Preferred additional friction modifiers are esters and or
amides, having hydroxyl functionality such as those derived from
mono or poly carboxylic acids and a poly alcohol or alkanolamine.
Examples of such AFM's include: glycerol mono oleate;
pentaerythritol mono oleate; the reaction product of an animal or
vegetable oil or fatty acid or synthetic fatty acid and an
alkanolamine such as ethanolamine, diethanolamine or propanolamine;
the reaction product of a polyalkylene substituted succinic acid or
anhydride and a glycol such as ethylene glycol, propylene glycol or
polyalkylene glycol.
[0191] A derivative of a fatty acid and a polyamine is an essential
element in the use of the invention, whilst an AFM is not, but may
often be important in obtaining excellent performance. When an AFM
is present the weight ratio of a) a derivative of a fatty acid and
a polyamine (total weight when more than one such is present) and
b) an AFM (total weight when more than one such is present) is in
the proportion 1 to 10000 parts a) to 100 parts b), preferably 10
to 1000 parts a) to 100 parts b), preferably 30 to 500 parts a) to
100 parts b), preferably 50 to 3000 parts a) to 100 parts b).
[0192] The amount of the fuel additive of the invention, namely a
derivative of a fatty acid and a polyamine, and an AFM when an AFM
is present (total amounts of each class) is preferably up to 10,000
ppm in the fuel, preferably up to 1,000 ppm, preferably from 1 to
500 ppm, preferably 10 to 200 ppm, and preferably 15 to 100
ppm.
[0193] An important additive which may present in certain preferred
embodiments is a dispersant or detergent. This is preferably a
nitrogen containing compound. This may suitably be present in the
fuel at a treat rate in the range 0.1 to 250 ppm, preferably 1 to
100 ppm (total amount when more then one is present). Some of the
AFMs mentioned above also have dispersant or detergency properties,
namely: [0194] Polyethers [0195] Polyetheramines [0196] Reaction
products of acylating agents and amines, for example
poly(isobutenylsuccinimides) (PIBSIs) [0197] Polyalkylene amines
[0198] Mannich bases based on tertiary alky substituted phenol and
C1-20 primary amines or polyalkylene amines [0199] Mixtures
containing any of these.
[0200] Preferred dispersants or detergents include dispersants or
detergents of the following categories: [0201] 1. Reaction products
of acylating agents and amines, for example
poly(isobutenylsuccinimides and poly(isobutenylsuccinamides),
[0202] 2. polyetheramines, [0203] 3. hydrocarbyl-substituted amines
wherein the hydrocarbyl substituent is substantially aliphatic and
contains at least 8 carbon atoms, [0204] 4. nitrogen-containing
condensates of a phenol, aldehyde and primary or secondary amine;
and [0205] 5. quaternary ammonium salts.
[0206] A carrier oil (as defined above under the heading "a)
carrier oil") above may advantageously be used with a dispersant or
detergent, including those of class 1-5 mentioned above.
[0207] Preferred dispersants or detergents of preceding numbered
categories 2, 3 or 4 are as described above in relation to such
compounds as AFMS.
[0208] A reaction product of acylating agents and amines, for
example poly(isobutenyl succinimides) and
poly(isobutenylsuccinamides), is suitably a reaction product of
poly(isobutenyl)succinic acid anhydride in which the
poly(isobutenyl) moiety is of MW from 650 to 1400; and a polyamine
preferably having from 4 to 50 carbon atoms preferably 4 to 20
carbon atoms, and preferably from 2 to 10 nitrogen atoms,
preferably 3 to 6 nitrogen atoms. Especially preferred polyamines
include ethylene diamine (EDA), diethylene triamine (DETA),
triethylene tetramine (TETA), tetraethylene pentamine (TEPA),
pentaethylene hexamine (PEHA) and dimethylaminopropylamine
(DMAPA).
[0209] Suitable quaternary ammonium salts are the reaction products
of compounds as described in immediately preceding sections 1, 3
and 4, which further comprise a tertiary amine group; and a
quaternizing agent. The quaternizing agent may suitably be selected
from the group consisting of dialkyl sulphates; an ester of a
carboxylic acid; alkyl halides; benzyl halides; hydrocarbyl
substituted carbonates; and hydrocarbyl epoxides in combination
with an acid or mixtures thereof.
[0210] Preferred quaternising agents for use herein include
dimethyl oxalate, methyl 2-nitrobenzoate, methyl salicylate and
styrene oxide or propylene oxide optionally in combination with an
additional acid.
[0211] When a compound is a dispersant or detergent and an AFM
herein, it may count as part of the defined complement of each.
[0212] In accordance with a sixth aspect of the present invention
there is provided a compound which comprises:
(1) a fatty acid residue having more than 12 carbon atoms and at
least one carboxylic group; and (2) a polyamine residue having more
than two nitrogen atoms; wherein the mole ratio of the carboxylic
groups to nitrogen atoms used to form the compound is greater than
0.8 carboxylic groups per 1 nitrogen atom.
[0213] In accordance with a seventh aspect of the present invention
there is provided a method of preparing a compound of the fifth
aspect, comprising reacting
(1) a fatty acid having more than 12 carbon atoms and at least one
carboxylic group and (2) a polyamine having more than two nitrogen
atoms; at a mole ratio of the reactant compounds greater than 0.8
carboxylic groups per 1 nitrogen atom.
[0214] In one embodiment the fatty acid and the polyamine are mixed
at a temperature of, for example, 20 to 100.degree. C. to make a
salt of the fatty acid and the polyamine.
[0215] In one embodiment a fatty acid amide is prepared by a
dehydration-condensation reaction between the fatty acid and the
polyamine, for example at a temperature of 20 to 200.degree. C.
under atmospheric or reduced pressure.
[0216] In accordance with an eighth aspect of the present invention
there is provided a fuel composition, lubricant composition, or
additive composition; each comprising a compound in accordance with
the fifth aspect.
[0217] The compound is preferably present in the composition of the
seventh aspect in an amount up to 10,000 ppm, preferably up to
1,000 ppm, preferably from 1 to 500 ppm, preferably 10 to 200 ppm,
and preferably 15 to 100 ppm.
[0218] In accordance with a ninth aspect of the present invention
there is provided an additive composition containing a solvent and
a compound in accordance with the fifth aspect, the additive
composition being adapted for addition into a fuel and/or
lubricant, with dilution therein of said compound.
[0219] Preferred aspects of any of the sixth, seventh, eighth or
ninth aspects are the features expressed above as the first,
second, third, fourth or fifth aspects, including preferred
features thereof.
[0220] The invention will now be further described with reference
to the following examples. Reference or comparative examples, not
intended to be covered by the claims defining our invention, are
denoted by the prefix "C".
EXAMPLES
A. Methodologies
[0221] A1. Compounds as defined above were prepared. A2. Suitable
hydrocarbons were identified for friction testing and compatability
studies. A3. Compatability in hydrocarbon liquids functional as a
fuel or lubricant was assessed. A4. Friction reducing properties of
the friction modifier compounds prepared by methods A1 were
assessed using the HFRR wear scar test and/or the TE77 sliding
friction test.
[0222] In greater detail:
A1. Compound Preparations
Example 1
Preparation of TOFA Diethylenetriamine Amide, Molar Ratio 3/1
[0223] Tall Oil Fatty Acid (TOFA), (20 g 0.07 mol) was dissolved in
toluene (22 g) in a round bottom flask fitted with a Dean and Stark
attachment. Diethylenetriamine (DETA), (2.4 g 0.023 M) was added to
the flask and the reaction mixture stirred under nitrogen and
refluxed at 115.degree. C. for 5 hours The water produced in the
reaction is removed by azeotropic distillation.
[0224] Further amides were prepared in a similar manner with the
acids, amines and ratios used identified in Table 2 below.
Example 5
Preparation of TOFA Diethylenetriamine Salt, Molar Ratio 3/1
[0225] TOFA (20 g 0.07 mol) was dissolved in toluene (22 g) in a
round bottom flask. DETA (2.4 g 0.023 M) was added to the flask and
the reaction mixture stirred under nitrogen for 1 hour until the
exothermic reaction subsided. The salt product was then
discharged.
[0226] Further amine salts were prepared in a similar manner with
the acids, amines and ratios used identified in Tables 3 and 4
below.
A2. Hydrocarbons
[0227] Typical properties for hydrocarbon A used in compatibility
testing and TE77 testing are as set out below.
TABLE-US-00001 TABLE 1 Property Unit Method Typical Results
Appearance Visual Clear and Bright Colour ASTM D1500 L0.5 Kinematic
Viscosity mm.sup.2/s ASTM D445 4.23 @100.degree. C. Kinematic
Viscosity mm.sup.2/s ASTM D445 18.9 @40.degree. C. Viscosity Index
ASTM D2270 131 Density at 15.degree. C. g/ml ASTL D4052 0.830 Pour
Point .degree. C. ASTM D97 -21 Flash Point .degree. C. ASTM D92 230
Noack Volatility % wt ASTM D5800B 11.4 Saturates % HPLC >99
Sulphur ppm ASTM D2622 3 Nitrogen ppm ASTM D4629 <1 Cold
Cranking -30.degree. C. mPa s ASTM D5293 1310 Polycyclic aromatics
% wt IP346 <0.5
[0228] The hydrocarbon used for HFRR testing was different, being a
unadditised unleaded gasoline, having a Research Octane Number of
95.
A3. Compatability Testing
[0229] Compatibility with a Hydrocarbon at 5% Concentration:
[0230] The solution of friction modifier in toluene was mixed with
hydrocarbon A to give a concentration of 5% wt/wt active friction
modifier. The evaluation was performed at room temperature. Fully
miscible mixtures were recorded as Pass (P), and
immiscible/separated mixtures recorded as Did Not Pass (DNP).
Compatibility with a Hydrocarbon at 10% Concentration:
[0231] The solution of friction modifier in toluene was mixed with
hydrocarbon A to give a concentration of 10% active friction
modifier. The evaluation was performed at room temperature. Fully
miscible mixtures were recorded as Pass (P), and
immiscible/separated mixtures recorded as Did Not Pass (DNP).
A4. Friction Reducing Testing
TE 77 Test:
[0232] The TE77 reciprocating sliding test was used. This employed
a Cameron-Plint TE77 High Frequency Reciprocating Tribometer. The
piston stroke was set at .+-.12.4 mm, and the frequency at 25
Hz.
[0233] The TE77 Tribometer was fitted with a section of Ford
F6173038 liner and a section of the corresponding Ford F6165200
compression piston ring.
[0234] The liner sample was situated in the sample bath fixed on a
heated bed to enable the temperature of the sample to be adjusted
according to demand.
[0235] The sample bath was filled with 10 mls of pure hydrocarbon
A.
[0236] Before each experiment the machine was run for a period of
time at a reduce load (10N) to ensure the system had achieved
thermal equilibrium before testing began. Once thermal equilibrium
was achieved, the load was increased to 75N and run for 40 minutes
to establish a baseline. The data acquisition sampling occurred
every second throughout the test.
[0237] After approximately 40 minutes had passed, 0.1 mls of
hydrocarbon containing 100000 ppm (10% active) additive was added
to the oil, providing the test hydrocarbon with 1000 ppm of the
active.
[0238] Following the addition of the additive the test continued to
run for a further 50 minutes.
[0239] At 30 minutes (prior to the additive addition) the friction
force was logged at 50,000 Hz.
[0240] At 75 minutes (after 35 minutes post the addition of the
additive) the friction force was logged at 50,000 Hz.
[0241] From this the maximum range (minimum to maximum) was
calculated for each set of data.
[0242] From this the percentage reduction with the use of the
additive was determined.
[0243] From the data acquired an average for the Coefficient of
Friction (.mu.) prior to the introduction of the additive was
determined by taking the averages of the values recorded between 26
to 39 minutes. The percentage change in Coefficient of Friction
(.mu.) was then calculated from the acquired Coefficient of
Friction (.mu.) against the average of the Coefficient of Friction
(.mu.) prior to the introduction of the additive.
[0244] A temperature of 125.degree. C. and a load of 75 N was
chosen to screen the compounds. The additives were ranked for
performance in terms of the percentage change in Coefficient of
Friction.
HFRR Test
[0245] The standard test for diesel is IP 450: "Diesel
fuel--Assessment of lubricity using the high-frequency
reciprocating rig (HFRR)", measuring wear scar diameter (WSD). As
mentioned above, the hydrocarbon used for the tests undertaken in
the context of this invention was gasoline. The test used was
similar to the IP 450 test, except the test was performed at
25.degree. C. instead of 60.degree. C. and used a modified sample
holder which holds 6 ml of sample and has a closed lid, instead of
a 2 ml sample.
B. Compounds Tested and Test Results of Same
B1. Amides
Per Method of Example 1 Given Above
TABLE-US-00002 [0246] TABLE 2 Molar Compat. Compat. TE77 Poly-
Ratio with HC with HC HFRR max. % Example Acid amine Acid/Polyamine
5% 10% WSD change .mu. Base HC 797 .mu.m 1 TOFA DETA 3/1 P P 268
.mu.m 54% 2C TOFA DETA 2/1 DNP DNP 3C n-hexanoic DETA 3/1 541 .mu.m
22% acid 4 isostearic DETA 3/1 P 389 .mu.m 48% acid
B2. Salts
Per Method of Example 5 Given Above
TABLE-US-00003 [0247] TABLE 3 Molar Compat. Compat. TE77 Poly-
Ratio with HC with HC HFRR max. % Example Acid amine Acid/Polyamine
5% 10% WSD change .mu. Base HC 797 .mu.m 5 TOFA DETA 3/1 P P 226
.mu.m 41% 6C TOFA DETA 2/1 DNP DNP 7C n hexanoic DETA 3/1 DNP 511
.mu.m 20% acid
[0248] A further series of amine salts were prepared. In this case,
the required amount of polyamine was added to a 50% solution of
TOFA in toluene and the reaction mixture stirred under nitrogen for
1 hour until the exothermic reaction subsided.
TABLE-US-00004 TABLE 4 Compatibility Acid Polyamine Ratio
Acid/amine with HC 5% 8C TOFA EDA 2/1 DNP 9 TOFA DETA 3/1 P 10C
TOFA TETA 2/1 DNP 11C TOFA TETA 3/1 DNP 12 TOFA TETA 4/1 P 13C TOFA
TEPA 2/1 DNP 14C TOFA TEPA 3/1 DNP 15C TOFA TEPA 4/1 DNP 16 TOFA
TEPA 5/1 P 17C n octanoic acid DETA 2/1 DNP 18C n octanoic acid
DETA 3/1 DNP 19C n decanoic acid DETA 2/1 DNP 20C n decanoic acid
DETA 3/1 DNP 21C n dodecanoic DETA 2/1 DNP acid 22C n dodecanoic
DETA 3/1 DNP acid 23C n octanoic acid TETA 4/1 DNP 24C n octanoic
acid TEPA 5/1 DNP 25C n decanoic acid TETA 4/1 DNP 26C n decanoic
acid TEPA 5/1 DNP 27C n dodecanoic TETA 4/1 DNP acid 28C n
dodecanoic TEPA 5/1 DNP acid EDA = ethylene diamine. DETA =
diethylene triamine TETA = triethylene tetramine. TEPA =
tetraethylene pentamine
Example 29
[0249] A second sample of the amide used in Example 4 was prepared
as follows:
Preparation of Isostearic Acid Diethylenetriamine Amide, Molar
Ratio 3/1
[0250] Isostearic acid (sourced from Croda with trade name Priosine
3501) (4115 g, 13.95 mol) was dissolved in toluene (4343 g) in an
oil jacketed reaction vessel fitted with an overhead stirrer and a
Dean and Stark attachment. DETA (479 g, 4.65 mol) was added to the
reactor over a 10 minute period and at such a rate that the
temperature in the flask was maintained below 30.degree. C. The
reaction mixture was stirred under nitrogen and refluxed at
117.degree. C. for 5 hours. Water produced in the reaction was
removed by azeotropic distillation.
Example 30
[0251] The amide of Example 29 was added to a CEC RF02 reference
fuel at a treat rate of 150 mg/litre active. The RF02 reference
fuel characteristics are given in Table 5
TABLE-US-00005 TABLE 5 Specification and Properties of RF02
Basefuel Specification limits Test Description Min Max Results
Units Method Density at 15.degree. C. 0.740 0.754 0.7490 g/mL ASTM
D4052 Distillation ASTM D86 I.B.Pt. 33.3 .degree. C. Evaporated at
70.degree. C. 24 40 31.4 % Evaporated at 100.degree. C. 50 58 52.5
% Evaporated at 150.degree. C. 83 89 84.5 % F.B.Pt. 190 210 208.7
.degree. C. Residue 2 0.9 % vol R.O.N. 95 96.4 Units ASTM D2699
M.O.N. 85 87.1 Units ASTM D2700 Aromatics 29 35 29.6 % vol ASTM
D1319 Olefins 10 0.7 % vol ASTM D1319 Saturates 69.7 % vol ASTM
D1319 Reid Vapour Pressure 56 60 56.3 kPa ASTM D323 Benzene 1
<0.1 % v/v EN 238 Oxidation Stability 480 >480 minutes ASTM
D525 Gum, - washed 4 <1 mg/100 mL ASTM D381 Copper Corrosion, 3
hrs at 1B ASTM D130 50.degree. C. Lead 5 <2.5 mg/L EN 237
Phosphorous 1.3 <0.2 mg/L ASTM D3231 Sulphur 10 2.8 mg/kg ASTM
D5453 Oxygen Content 1 0.77 % mass IP 466
Example 31
Vehicle Testing Procedure
[0252] Testing was undertaken using a 2008 Year 1.6 litre Proton
GEN-2 Persona car.
[0253] The vehicle was fitted to a standard emission/fuel economy
measurement system incorporating: [0254] 48'' single roll DC
electric dynamometer [0255] Speed tracking cooling fan [0256] Raw
engine out & tailpipe real time modal analysis, CO.sub.2
tracer, % EGR (Exhaust Gas Recirculation) and bag
[0257] A fuel change rig was used to allow changes between basefuel
and test fuel to be made without stopping the engine.
[0258] The test cycle used was as follows:
Warm Up Phase
TABLE-US-00006 [0259] Vehicle warm-up, 4 EUDC (Extra Urban Driving
Cycles) Basefuel stabilisation 30 minutes
Testing Phase
TABLE-US-00007 [0260] Basefuel 7.5 minutes Basefuel + Additive of
Example 29 30 minutes Basefuel 7.5 minutes Basefuel
re-stabilisation 30 minutes
[0261] During the basefuel stabilisation and 45 minute testing
period the vehicle was operated at 1863 rpm in 4.sup.th gear giving
a vehicle speed equivalent under level road conditions of 53 kph.
Modal CO.sub.2 measurements were used to measure vehicle fuel
consumption.
[0262] The results are shown in Table 6 and FIG. 1.
TABLE-US-00008 TABLE 6 Results of Fuel Economy Testing Average
CO.sub.2 Treat Rate Measurement % Improvement Fuel Additive mg/l
active g/s in Fuel Economy RF02 None 1.533 RF02 Example 29 150
1.518 0.98
[0263] The additive of Example 29 (isostearic DETA amide at 150
mg/l) gave a rapid reduction of CO2 emissions and fuel consumption
of 1.0%.
[0264] It can be seen that good results were consistently achieved
using compounds formed from fatty acids of the longer carbon chain
lengths and polyamines having 3 or more amine groups/nitrogen
atoms, at the molar ratios of carboxylic acids to polyamine
reactants which provided carboxylic acid groups commensurate with
amine groups.
* * * * *