U.S. patent application number 13/981465 was filed with the patent office on 2013-12-19 for fuel composition.
This patent application is currently assigned to Dupont Nutrition Biosciences APS. The applicant listed for this patent is Jens Mogens Nielsen. Invention is credited to Jens Mogens Nielsen.
Application Number | 20130333277 13/981465 |
Document ID | / |
Family ID | 43881600 |
Filed Date | 2013-12-19 |
United States Patent
Application |
20130333277 |
Kind Code |
A1 |
Nielsen; Jens Mogens |
December 19, 2013 |
FUEL COMPOSITION
Abstract
The present invention provides a fuel composition comprising:
(a) a fuel; (b) polyglycerol polyricinoleic acid (c) a
monoglyceride of a fatty acid.
Inventors: |
Nielsen; Jens Mogens;
(Galten, DK) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Nielsen; Jens Mogens |
Galten |
|
DK |
|
|
Assignee: |
Dupont Nutrition Biosciences
APS
Copenhagen K
DK
|
Family ID: |
43881600 |
Appl. No.: |
13/981465 |
Filed: |
February 23, 2012 |
PCT Filed: |
February 23, 2012 |
PCT NO: |
PCT/IB12/50835 |
371 Date: |
July 24, 2013 |
Current U.S.
Class: |
44/301 ; 44/389;
44/639 |
Current CPC
Class: |
C10L 1/328 20130101;
C10L 2300/20 20130101; C10L 1/191 20130101 |
Class at
Publication: |
44/301 ; 44/389;
44/639 |
International
Class: |
C10L 1/32 20060101
C10L001/32 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 24, 2011 |
GB |
1103181.2 |
Claims
1. A fuel composition comprising: (a) a fuel; (b) polyglycerol
polyricinoleic acid; and (c) a monoglyceride of a fatty acid.
2. A fuel composition according to claim 1 wherein the fuel is
selected from diesel, heavy fuel oil, marine gasoil and
kerosene.
3. A fuel composition according to claim 1 or 2 wherein the fuel is
diesel.
4. A fuel composition according to any one of the preceding claims
wherein the polyglycerol comprises one or a mixture of more than
one of the polyglycerols selected from the group consisting of
diglycerol, triglycerol, tetraglycerol, pentaglycerol,
hexaglycerol, heptaglycerol, octaglycerol, nonaglycerol and
decaglycerol.
5. A fuel composition according to any one of the preceding claims
wherein the fatty acid polymerised chain length of the
polyricinoleic acid is from 1 to 10.
6. A fuel composition according to any one of the preceding claims
wherein the polyglycerol polyricinoleic acid is prepared from
hydroxy fatty acids of hydrogenated or non-hydrogenated castor
oil.
7. A fuel composition according to any one of the preceding claims,
wherein the polyglycerol polyricinoleic acid has a hydroxyl value
of about 20 to about 120 mgKOH.
8. A fuel composition according to any one of the preceding claims,
wherein the monoglyceride of a fatty acid is monoglyceride of a
fatty acid of a C16 to C22 fatty acid.
9. A fuel composition according to claim 8, wherein the
monoglyceride of a fatty acid is monoglyceride of a C16 or C18
fatty acid.
10. A fuel composition according to any one of the preceding
claims, wherein the monoglyceride of a fatty acid is monoglyceride
of unsaturated fatty acid.
11. A fuel composition according to any one of the preceding
claims, wherein the monoglyceride of a fatty acid is monoglyceride
of mono or di unsaturated fatty acid.
12. A fuel composition according to any one of the preceding
claims, wherein the monoglyceride of a fatty acid is a mixture of
1) monoglyceride of saturated C16 fatty acid 2) monoglyceride of
saturated C18 fatty acid 3) monoglyceride of mono unsaturated C18
fatty acid; and 4) monoglyceride of di unsaturated C18 fatty
acid.
13. A fuel composition according to any one of the preceding
claims, wherein the monoglyceride of a fatty acid is a mixture of
1) palmitic acid monoglyceride 2) stearic acid monoglyceride 3)
oleic acid monoglyceride; and 4) linoleic acid monoglyceride.
14. A fuel composition according to any one of the preceding
claims, wherein the ratio of (b) polyglycerol polyricinoleic acid
to (c) a monoglyceride of a fatty acid is from 0.7:0.3 to
0.1:0.9.
15. A fuel composition according to any one of the preceding
claims, wherein the ratio of (b) polyglycerol polyricinoleic acid
to (c) a monoglyceride of a fatty acid is from 0.625:0.375 to
0.125:0.875.
16. A fuel composition according to any one of the preceding
claims, wherein the fuel composition comprises (b) polyglycerol
polyricinoleic acid and (c) a monoglyceride of a fatty acid in a
total combined amount of from 0.1 to 2.0 wt % based on the total
fuel composition.
17. A fuel composition according to any one of the preceding
claims, wherein the fuel composition comprises (b) polyglycerol
polyricinoleic acid and (c) a monoglyceride of a fatty acid in a
total combined amount of from 0.1 to 1.0 wt % based on the total
fuel composition.
18. A fuel composition according to any one of the preceding
claims, wherein the fuel composition comprises (b) polyglycerol
polyricinoleic acid and (c) a monoglyceride of a fatty acid in a
total combined amount of from 0.5 to 1.0 wt % based on the total
fuel composition.
19. A fuel composition according to any one of the preceding
claims, wherein the fuel composition further comprises (d)
water.
20. A fuel composition according to claim 19, wherein the fuel
composition further comprises (d) water in an amount of from 10 to
70 wt % based on the total fuel composition.
21. A fuel composition according to claim 19, wherein the fuel
composition further comprises (d) water in an amount of from 30 to
60 wt % based on the total fuel composition.
22. A fuel composition according to claim 19, wherein the fuel
composition further comprises (d) water in an amount of from 33 to
50 wt % based on the total fuel composition.
23. A fuel composition according to any one of the preceding
claims, wherein the fuel composition comprises glycerol in an
amount of less than 0.1 wt % based on the total fuel
composition.
24. A method for improving the stability of a fuel composition
containing fuel and water, the method comprising mixing with the
fuel and water, (b) polyglycerol polyricinoleic acid; and (c) a
monoglyceride of a fatty acid.
25. A method according to claim 24, characterised by the features
of any one of claims 2 to 19.
26. Use of polyglycerol polyricinoleic acid and a monoglyceride of
a fatty acid for improving the stability of a fuel composition
containing fuel and water.
27. A kit for preparing a fuel composition as defined in any one of
claims 1 to 23, the kit comprising (a) polyglycerol polyricinoleic
acid; and (b) a monoglyceride of a fatty acid, in separate packages
or containers, or combined in a single package or container;
together with instructions for use to prepare the fuel
composition.
28. A fuel composition substantially as hereinbefore described with
reference to any one of the Examples.
29. A method substantially as hereinbefore described with reference
to any one of the Examples.
30. A use substantially as hereinbefore described with reference to
any one of the Examples.
31. A kit substantially as hereinbefore described with reference to
any one of the Examples.
Description
[0001] The present invention relates to a composition. In
particular the present invention relates to fuel compositions
having reduced nitrogen oxide emissions when combusted.
[0002] As discussed in U.S. Pat. No. 7,491,247 environmental
considerations and government regulations have increased the need
to reduce nitrogen oxide (NOx) production. Nitrogen oxides comprise
a major irritant in smog and are believed to contribute to
tropospheric ozone which is a known threat to health. Relatively
high flame temperatures reached in internal combustion engines, for
example diesel-fuelled engines, increase the tendency for the
production of nitrogen oxides (NOx). These are formed from both the
combination of nitrogen and oxygen in the combustion chamber and
from the oxidation of organic nitrogen species in the fuel.
[0003] Various methods for reducing NOx production include the use
of catalytic converters, engine timing changes, exhaust
recirculation, and the burning of "clean" fuels. These methods are
generally too expensive and/or too complicated to be placed in
widespread use. The rates at which NOx are formed is related to the
flame temperature; a small reduction in flame temperature can
result in a large reduction in the production of nitrogen
oxides.
[0004] It has been shown that introducing water into the combustion
zone can lower the flame temperature and thus lower NOx production,
however; the direct injection of water requires costly and
complicated changes in engine design. Further attempts to use water
to reduce flame temperature include the use of aqueous fuels, i.e.,
incorporating both water and fuel into an emulsion. Problems that
may occur from long-term use of aqueous fuels include precipitate
depositions from coalescing ionic species resulting in filter
plugging and inorganic post combustion deposits resulting in turbo
fouling. Another problem related to aqueous fuel compositions is
that they often require substantial engine modifications, such as
the addition of in-line homogenizers, thereby limiting their
commercial utility.
[0005] Another method for introducing water into the combustion
area is to use fuel emulsions in which water is emulsified into a
fuel continuous phase, i.e., invert fuel emulsions. A problem with
these invert fuel emulsions is obtaining and maintaining the
stability of the emulsion under conventional use conditions.
Gravitational phase separation (during storage) and high
temperature high pressure/shear flow rate phase separation (in a
working engine) of these emulsions present the major hurdle
preventing their commercial use.
[0006] The present invention addresses the problems associated with
the use of fuel emulsion compositions by providing a stable fuel
emulsion composition with the beneficial reduction in NOx
emissions.
[0007] The present invention alleviates the problems of the prior
art.
[0008] In one aspect the present invention provides a fuel
composition comprising:
(a) a fuel; (b) polyglycerol polyricinoleic acid and (c) a
monoglyceride of a fatty acid.
[0009] In one aspect the present invention provides a method for
improving the stability of a fuel composition containing fuel and
water, the method comprising mixing with the fuel and water, (a)
polyglycerol polyricinoleic acid; and (b) a monoglyceride of a
fatty acid.
[0010] In one aspect the present invention provides use of
polyglycerol polyricinoleic acid and a monoglyceride of a fatty
acid for improving the stability of a fuel composition containing
fuel and water.
[0011] In one aspect the present invention provides a kit for
preparing a fuel composition as defined herein, the kit comprising
(a) polyglycerol polyricinoleic acid and (b) a monoglyceride of a
fatty acid, in separate packages or containers, or combined in a
single package or container; together with instructions for use to
prepare the fuel composition.
[0012] We have shown that when each a polyglycerol polyricinoleic
acid or a monoglyceride of a fatty acid are used alone as an
emulsifier in a fuel containing water, that single emulsifier fails
to provide a fuel/water emulsion which is stable during storage. In
contrast we have surprisingly found that the specific combination
of these two emulsifiers, namely a polyglycerol polyricinoleic acid
and a monoglyceride of a fatty acid provides fuel and water
emulsions which are stable at least with regard to separation until
the combustion of the fuel.
[0013] For ease of reference these and further aspects of the
present invention are now discussed under appropriate section
headings. However, the teachings under each section are not
necessarily limited to each particular section.
[0014] Composition
[0015] As previously mentioned, in one aspect the present invention
provides a fuel composition comprising: (a) a fuel; (b)
polyglycerol polyricinoleic acid and (c) a monoglyceride of a fatty
acid.
[0016] Polyglycerol Polyricinoleic Acid
[0017] As is understood by one skilled in the art polyglycerol
polyricinoleic acid is an emulsifier comprising a polyglycerol
`backbone` onto which ricinoleic acid side chains are attached.
Ricinoleic acid ((9Z,12R)-12-Hydroxyoctadec-9-enoic acid) has
hydroxy group at the 12 position onto which further ricinoleic side
chains may be attached.
[0018] The polyglycerol may be of any suitable length. In one
aspect the polyglycerol comprises one or a mixture of more than one
of the polyglycerols selected from the group consisting of
diglycerol, triglycerol, tetraglycerol, pentaglycerol,
hexaglycerol, heptaglycerol, octaglycerol, nonaglycerol and
decaglycerol. In one aspect the polyglycerol comprises one or a
mixture of more than one of the polyglycerols selected from the
group consisting of diglycerol, triglycerol and tetraglycerol.
[0019] The ricinoleic acid side chains, namely the polyricinoleic
acid, attached to the polyglycerol may be of any suitable length.
In one aspect the fatty acid polymerised chain length of the
polyricinoleic acid is from 1 to 10. In another aspect the fatty
acid polymerised length of the polyricinoleic acid is from 4 to
6.
[0020] The ricinoleic acid may be provided from any suitable
source. Thus in one aspect, the polyglycerol polyricinoleic acid is
prepared from hydroxy fatty acids of hydrogenated or
non-hydrogenated castor oil.
[0021] In one aspect the polyglycerol polyricinoleic acid has a
hydroxyl value of about 20 to about 120 mgKOH.
[0022] In a further and preferred aspect the polyglycerol
polyricinoleic acid has at least one of the following
characteristics: [0023] i) an acid value of less than or equal to
10.0 mg KOH; [0024] ii) a hydroxyl value of about 80.0 to about
100.0 mgKOH; [0025] iii) an iodine value of about 72 to about 103 g
I.sub.2.
[0026] Preferably the polyglycerol polyricinoleic acid has more
than one of the characteristics i) to iii). More preferably the
polyglycerol polyricinoleic acid has all of the characteristics i)
to iii).
[0027] Monoglyceride of a Fatty Acid
[0028] The monoglyceride of a fatty acid may be a monoglyceride
having any suitable fatty chain lengths. The monoglyceride of a
fatty acid may be a monoglyceride of a single fatty acid, or
monoglycerides of a mixture of fatty acids. The fatty chain lengths
of the monoglycerides in a mixture of monoglycerides need not be of
the same length. Typically the monoglyceride of a fatty acid is
monoglyceride of a fatty acid of a C12 to C22 fatty acid.
Preferably the monoglyceride of a fatty acid is monoglyceride of a
C16 or C22 fatty acid. Preferably the monoglyceride of a fatty acid
is monoglyceride of a C16 or C18 fatty acid.
[0029] The fatty acid of the monoglyceride of a fatty acid may be
saturated fatty acid, unsaturated fatty acid or a mixture of
saturated fatty acid and unsaturated fatty acid. In one aspect the
monoglyceride of a fatty acid is monoglyceride of unsaturated fatty
acid. Preferably the monoglyceride of a fatty acid is a
monoglyceride of mono or di unsaturated fatty acid.
[0030] Preferred monoglycerides of a fatty acid may be selected
from [0031] monoglyceride of saturated C16 fatty acid [0032]
monoglyceride of saturated C18 fatty acid [0033] monoglyceride of
mono unsaturated C18 fatty acid [0034] monoglyceride of di
unsaturated C18 fatty acid [0035] monoglyceride of saturated C16
fatty acid; and monoglyceride of saturated C18 fatty acid [0036]
monoglyceride of saturated C16 fatty acid; and monoglyceride of
mono unsaturated C18 fatty acid [0037] monoglyceride of saturated
C16 fatty acid; and monoglyceride of di unsaturated C18 fatty acid
[0038] monoglyceride of saturated C18 fatty acid; and monoglyceride
of mono unsaturated C18 fatty acid [0039] monoglyceride of
saturated C18 fatty acid; and monoglyceride of di unsaturated C18
fatty acid [0040] monoglyceride of mono unsaturated C18 fatty acid;
and monoglyceride of di unsaturated C18 fatty acid [0041]
monoglyceride of saturated C16 fatty acid; and monoglyceride of
saturated C18 fatty acid; and monoglyceride of mono unsaturated C18
fatty acid [0042] monoglyceride of saturated C16 fatty acid; and
monoglyceride of saturated C18 fatty acid; and monoglyceride of di
unsaturated C18 fatty acid [0043] monoglyceride of saturated C16
fatty acid; and monoglyceride of mono unsaturated C18 fatty acid;
and monoglyceride of di unsaturated C18 fatty acid [0044]
monoglyceride of saturated C18 fatty acid; and monoglyceride of
mono unsaturated C18 fatty acid; and monoglyceride of di
unsaturated C18 fatty acid [0045] monoglyceride of saturated C16
fatty acid; and monoglyceride of saturated C18 fatty acid; and
monoglyceride of mono unsaturated C18 fatty acid; and monoglyceride
of di unsaturated C18 fatty acid
[0046] Preferred monoglycerides of a fatty acid may be selected
from [0047] palmitic acid monoglyceride [0048] stearic acid
monoglyceride [0049] oleic acid monoglyceride [0050] linoleic acid
monoglyceride [0051] palmitic acid monoglyceride; and stearic acid
monoglyceride [0052] palmitic acid monoglyceride; and oleic acid
monoglyceride [0053] palmitic acid monoglyceride; and linoleic acid
monoglyceride [0054] stearic acid monoglyceride; and oleic acid
monoglyceride [0055] stearic acid monoglyceride; and linoleic acid
monoglyceride [0056] oleic acid monoglyceride; and linoleic acid
monoglyceride [0057] palmitic acid monoglyceride; and stearic acid
monoglyceride; and oleic acid monoglyceride [0058] palmitic acid
monoglyceride; and stearic acid monoglyceride; and linoleic acid
monoglyceride [0059] palmitic acid monoglyceride; and oleic acid
monoglyceride; and linoleic acid monoglyceride [0060] stearic acid
monoglyceride; and oleic acid monoglyceride; and linoleic acid
monoglyceride [0061] palmitic acid monoglyceride; and stearic acid
monoglyceride; and oleic acid monoglyceride; and linoleic acid
monoglyceride
[0062] As discussed above, each of the polyglycerol polyricinoleic
acid and the monoglyceride of a fatty acid alone do not provide a
stable fuel and water emulsion. Therefore each of these components
must be present in sufficient amounts, in relative and absolute
terms, to provide a stable emulsion. The emulsion must be stable
such that, in use, the water and the fuel do not separate. In use
the emulsion is typically formed shortly before it is required for
combustion. This is performed by combination of the essential
materials, namely the polyglycerol polyricinoleic acid, the
monoglyceride of a fatty acid, the fuel and the water. The emulsion
is then fed into the fuel delivery system to be combusted. Between
formation of the fuel emulsion and its eventual combustion, the
emulsion should not separate. This period between formation and
combustion may be relatively short if the emulsion is combusted
almost immediately. However, in a number of circumstances the
period may be longer. Examples of such circumstances include fuel
delivery systems in which a proportion of the fuel is combusted and
the remainder of the fuel is recirculated around the fuel delivery
system. This is common in diesel and marine gasoil engines. Further
circumstances are where an engine is shut down either completely or
partially (by shut down of one or more cylinders of a
multi-cylinder engine). During the period of shut down it is a
requirement that the fuel emulsion should not separate. If
separation were to occur, restarting of the engine or of the
inactive cylinder(s) may not be possible. Periods of stability
required by many industries are at least 1 hour, such as at least 2
hours, such as at least 3 hours.
[0063] In one aspect the present invention provides a fuel
composition comprising:
(a) a fuel; (b) polyglycerol polyricinoleic acid; (c) a
monoglyceride of a fatty acid; and (d) water, wherein the fuel
composition is an emulsion and wherein the emulsion is stable with
regard to separation of the emulsion for a period of at least 1
hour after the formation of the emulsion. Preferably the emulsion
is stable with regard to separation of the emulsion for a period of
at least 2 hours after the formation of the emulsion. Preferably
the emulsion is stable with regard to separation of the emulsion
for a period of at least 3 hours after the formation of the
emulsion.
[0064] In one aspect the ratio of (b) polyglycerol polyricinoleic
acid to (c) a monoglyceride of a fatty acid is from 0.9:0.1 to
0.1:0.9. In one aspect the ratio of (b) polyglycerol polyricinoleic
acid to (c) a monoglyceride of a fatty acid is from 0.7:0.3 to
0.1:0.9.
[0065] We have further found that although a broad range of ratios
provides advantages over the prior art systems, at a specific range
of ratios, particularly strong stability is observed. In one
preferred aspect the ratio of (b) polyglycerol polyricinoleic acid
to (c) a monoglyceride of a fatty acid is from 0.625:0375 to
0.125:0.875. In one highly preferred aspect, the monoglyceride of a
fatty acid is monoglyceride of a C16 or C18 fatty acid, the
polyglycerol polyricinoleic acid is prepared from hydroxy fatty
acids of hydrogenated or non-hydrogenated castor oil wherein the
polyglycerol comprises a mixture of polyglycerols selected from the
group consisting of diglycerol, triglycerol and tetraglycerol; and
the ratio of (b) polyglycerol polyricinoleic acid to (c) a
monoglyceride of a fatty acid is from 0.625:0.375 to
0.125:0.875.
[0066] When a mixture of (b) polyglycerol polyricinoleic acid and
(c) a monoglyceride of a fatty acid is provided in accordance with
the present invention, the mixture may be dosed in the water and
fuel composition in any suitable amount to provide an emulsion of
desired stability. In one aspect the fuel composition comprises (b)
polyglycerol polyricinoleic acid and (c) a monoglyceride of a fatty
acid in a total combined amount of from 0.1 to 2.0 wt % based on
the total fuel composition. In a further aspect the fuel
composition comprises (b) polyglycerol polyricinoleic acid and (c)
a monoglyceride of a fatty acid in a total combined amount of from
0.1 to 1.0 wt % based on the total fuel composition. In a further
aspect the fuel composition comprises (b) polyglycerol
polyricinoleic acid and (c) a monoglyceride of a fatty acid in a
total combined amount of from 0.5 to 1.0 wt % based on the total
fuel composition.
[0067] The polyglycerol polyricinoleic acid is dosed in the water
and fuel composition in any suitable amount to provide an emulsion
of desired stability. In one aspect the fuel composition comprises
polyglycerol polyricinoleic acid in an amount of from 0.05 to 2.0
wt % based on the total fuel composition. In a further aspect the
fuel composition comprises polyglycerol polyricinoleic acid in an
amount of from 0.05 to 1.0 wt % based on the total fuel
composition. In a further aspect the fuel composition comprises
polyglycerol polyricinoleic acid in an amount of from 005 to 0.8 wt
% based on the total fuel composition. In a further aspect the fuel
composition comprises polyglycerol polyricinoleic acid in an amount
of from 0.1 to 0.8 wt % based on the total fuel composition. In a
further aspect the fuel composition comprises polyglycerol
polyricinoleic acid in an amount of from 0.1 to 0.7 wt % based on
the total fuel composition. In a further aspect the fuel
composition comprises polyglycerol polyricinoleic acid in an amount
of from 0.125 to 0.625 wt % based on the total fuel
composition.
[0068] The monoglyceride of a fatty acid is dosed in the water and
fuel composition in any suitable amount to provide an emulsion of
desired stability. In one aspect the fuel composition comprises a
monoglyceride of a fatty acid in an amount of from 0.05 to 1.0 wt %
based on the total fuel composition. In a further aspect the fuel
composition comprises a monoglyceride of a fatty acid in an amount
of from 0.1 to 1.0 wt % based on the total fuel composition. In a
further aspect the fuel composition comprises a monoglyceride of a
fatty acid in an amount of from 0.2 to 1.0 wt % based on the total
fuel composition. In a further aspect the fuel composition
comprises a monoglyceride of a fatty acid in an amount of from 0.3
to 1.0 wt % based on the total fuel composition. In a further
aspect the fuel composition comprises a monoglyceride of a fatty
acid in an amount of from 0.375 to 0.875 wt % based on the total
fuel composition.
[0069] It is understood by one skilled in the art that
monoglycerides of fatty acids by the nature of their preparation
are typically supplied as a mixture of monoglycerides of a fatty
acid and diglycerides of a fatty acid. Such mixtures are referred
to by those skilled in the art as a mono-diglyceride of a fatty
acid. In one aspect, the monoglycerides of fatty acids for use in
the present invention are provided in a mixture of monoglyceride of
a fatty acid and diglyceride of a fatty acid, namely as a
mono-diglyceride of a fatty acid. Thus the present invention
provides [0070] a fuel composition comprising: [0071] (a) a fuel;
(b) polyglycerol polyricinoleic acid (c) a mixture of monoglyceride
of a fatty acid and diglyceride of a fatty acid. [0072] a method
for improving the stability of a fuel composition containing fuel
and water, the method comprising mixing with the fuel and water,
(a) polyglycerol polyricinoleic acid; and (b) a mixture of
monoglyceride of a fatty acid and diglyceride of a fatty acid
[0073] use of polyglycerol polyricinoleic acid and a mixture of
monoglyceride of a fatty acid and diglyceride of fatty acid for
improving the stability of a fuel composition containing fuel and
water.
[0074] The mixture of monoglycerides of fatty acids and
diglycerides of fatty acids may be a distilled product or a
non-distilled product, in a preferred aspect, the monoglyceride of
a fatty acid is a distilled monoglyceride of a fatty acid.
[0075] Fuel
[0076] As discussed herein, the emulsifiers described allow for the
preparation of an emulsion of fuel and water. A fuel suitable for
preparing into an emulsion but which has yet to be combined with
water is hereby encompassed within the present invention. However,
in a preferred aspect, the fuel containing the emulsifiers is
combined with water and the fuel composition further comprises (d)
water. It will be appreciated that in this aspect the fuel
composition may be prepared by first dosing the emulsifiers
(polyglycerol polyricinoleic acid and monoglyceride of a fatty
acid) into the fuel, such as marine gasoil (MGO), after which water
is dosed into the fuel/emulsifier blend.
[0077] The amount of water may be selected based on the
requirements of the combustion system, in one aspect the fuel
composition further comprises (d) water in an amount of from 10 to
70 wt % based on the total fuel composition. Preferably the water
is present in an amount of from 30 to 60 wt % based on the total
fuel composition. Preferably the water is present in an amount of
from 33 to 50 wt % based on the total fuel composition.
[0078] The composition according to the present invention may
comprise one or more additives for example, to improve various
aspects of the fuel to which the composition is typically added or
to improve various aspects of the combustion system performance.
Suitable additional additives include detergents, carrier oils,
anti-oxidants, corrosion inhibitors, colour stabilisers, metal
deactivators, cetane number improvers, other combustion improvers,
antifoams, pour point depressants, cold filter plugging
depressants, wax anti-settling additives, dispersants, deodorants,
dyes, smoke suppressants, lubricity agents, and other particulate
filter regeneration additives. However, in one aspect the fuel
composition comprises glycerol in an amount of less than 0.1 wt %
based on the total fuel composition, such as in an amount of less
than 0.05 wt % based on the total fuel composition, such as in an
amount of less than 0.02 wt % based on the total fuel composition,
such as in an amount of less than 0.01 wt % based on the total fuel
composition, such as in an amount of less than 0.005 wt % based on
the total fuel composition, such as in an amount of less than 0.001
wt % based on the total fuel composition.
[0079] The fuel may be any fuel suitable for combustion where
reduction of NOx is desired. In one aspect the fuel is a fuel for
spark ignition engines such as a gasoline engine. Preferably the
fuel is a fuel for a high compression spontaneous ignition engine.
In one aspect the fuel is selected from diesel, heavy fuel oil,
marine gasoil (MGO) and kerosene. The diesel may be biodiesel, low
sulphur diesel and ultra-low sulphur diesel. Preferably the fuel is
marine gasoil. The marine gasoil may be any suitable marine gasoil.
In one aspect it is a fuel having a (i) a density of 0.85-0.89
g/cm.sup.3, a cetane Number of approximately 45; and a flash point
of greater than 55.degree. C.
[0080] Kit
[0081] As discussed herein, in one aspect the present invention
provides a kit for preparing a fuel composition as defined herein,
the kit comprising (a) polyglycerol polyricinoleic acid; and (b) a
monoglyceride of a fatty acid, in separate packages or containers,
or combined in a single package or container; together with
instructions for use to prepare the fuel composition.
[0082] In one aspect (a) polyglycerol polyricinoleic acid and (b) a
monoglyceride of a fatty acid of a fatty acid are provided in
separate packages or containers. In one aspect (a) polyglycerol
polyricinoleic acid and (b) a monoglyceride of a fatty acid of a
fatty acid are provided combined in a single package or
container.
[0083] Aspects of the invention are defined in the appended
claims.
[0084] The present invention will now be described in further
detail in the following examples.
EXAMPLES
[0085] As discussed herein addition of water to fuels such as
diesel can reduce NOx pollution, for example and particularly from
ships. The presence of water reduces the combustion temperature in
the engine resulting in less NOx formation. It is understood that
up to 50% water addition may be required to obey future limits on
maximum NOX emission set for the future.
[0086] Typically on ship use of fuel and water emulsions is
achieved by preparation on board of emulsions. Thus the emulsions
require only 1-3 hours stability
[0087] In the following examples polyglycerol polyricinolate and
distilled monoglycerides were tested as emulsifiers for
water-in-fuel emulsions. As discussed herein, it was surprisingly
found that both emulsifiers when used alone failed in stabilising
the water-in-fuel emulsions, whereas the two emulsifiers in
combination created stable emulsions. The stable emulsion did not
undergo sedimentation of the water droplets during a 3 hour test
period.
[0088] GRINDSTED PGPR 90 a polyglycerol polyricinolate, and
specifically a polyglycerol ester of polycondensed fatty acids from
castor oil. GRINDSTED PGPR 90 is available from Danisco A/S,
Denmark. GRINDSTED PGPR 90 has i) an acid value of less than or
equal to 6 mg KOH; ii) a hydroxyl value of 80 to 100 mgKOH; and
iii) an iodine value of 72 to 103 g I.sub.2.
[0089] DIMODAN U/J a distilled monoglyceride, and specifically a
distilled monoglyceride made from refined sunflower oil. DIMODAN
U/J is available from Danisco A/S.
[0090] GRINDSTED PGPR 90 and DIMODAN U/J were tested at dosages
ranging from 0.6%-1.0% based on the total emulsion. The tests were
performed at water contents of 33% and 50% at temperatures of
40.degree. C. and 55.degree. C.
[0091] Method
[0092] Test conditions: temperature range 40'C-55.degree. C. and
water content 33%-50% based on the emulsion.
[0093] Emulsions were characterised in respect to emulsion
stability (phase separation and sedimentation), water droplet size
distribution (droplet size by NMR and CLSM) and viscosity from flow
curves.
[0094] Preparation of Emulsions:
[0095] The emulsifiers were dissolved in 40/55.degree. C. MSO and
40/55.degree. C. water was added to the Marine Gasoil (MGO) during
high speed mixing with Ultra Turrax at 20500 rpm for 64 sec as
standard.
[0096] The emulsions were investigated according to below described
methods and subsequently stored at 40/55.degree. C.
[0097] Emulsions Stability
[0098] The emulsions were evaluated visually for stability. Two
phenomena were evaluated: water droplet sedimentation due to
gravity force and water separation due to coalescence. The samples
were monitored for 3 hours.
[0099] Microscopy:
[0100] CLSM (Confocal Laser Scanning Microscope--Leica TCS SP2)
using Nile Red and FITC for MGO and water droplets staining,
respectively.
[0101] Water Droplet Size Distribution:
[0102] The water droplet size distribution was measured by NMR
(Bruker Minispec mq20 NMR Analyzer) based on log-normal size
distribution.
[0103] Bulk Rheology
[0104] A flow curve was measured for selected emulsions just after
preparation in the shear rate range 10-2000 l/s using Physica
Rheoplus, measuring system DG26.7-SN12751; d=0 mm,
[0105] Results and Discussion
[0106] The results show that mixing ratios of PGPR90:DIMODAN U/J in
the range 62.5:37.5 to 12.5:87.5 prevented sedimentation and water
phase separation throughout the 3 hours test phase. Ratios outside
above mixing ratios resulted in some sedimentation but less than
compared to each of the emulsifiers used alone.
[0107] Test PGPR 90 and DIMODAN U/J at the ratios shown below and a
total dosage of 1% in MGO Shell containing 33% water. The
emulsifiers were added and dissolved into the MGO at 40.degree. C.
40.degree. C. was maintained during mixing with Ultra Turrax at
20500 rpm for 64 seconds. The results are shown in Table 1.
TABLE-US-00001 TABLE 1 Temp Trial PGPR 90 % U/J % Water % MGO
.degree. C. D50.0 .mu.m 1 1 0 33 Shell 40 10.3 2 0.875 0.125 33
Shell 40 9.9 3 0.750 0.250 33 Shell 40 10.6 4 0.625 0.375 33 Shell
40 11.5 5 0.500 0.500 33 Shell 40 11.5 6 0.375 0.625 33 Shell 40
10.4 7 0.250 0.750 33 Shell 40 9.9 8 0.125 0.875 33 Shell 40 9.9 9
0 1 33 Shell 40 10.7
[0108] The droplet size distribution in table 1 shows a nearly
constant D50.0 independently of the mixing ratio between PGPR 90
and DIMODAN U/J.
[0109] In FIG. 1 the flow curves shows that emulsions with PGPR 90
behave nearly Newtonian in the complete shear rate range in
contrast to emulsions with only distilled monoglycerides added. The
Newtonian viscosity was approx. 7 mPa s
[0110] FIG. 2 shows images of the samples of Table 1. For each
composition, images were recorded at 1, 2 and 3 hours after mixing.
FIG. 3 shows graphically the degree of sedimentation expressed as
amount of free MGO on top of the samples. The graph was constructed
by measuring and calculating the height of the free oil layer in
percentage of the total emulsion height by image analysis. Five
samples in the mid-range perform excellently with no sedimentation
within the first 3 hours Samples with only PGPR 90 or DIMODAN U/J
had severe sedimentation
[0111] FIG. 2 and FIG. 3 clearly show, that PGPR:DIMODAN in the
mixing ratios 62.5:37.5:12.5:87.5 provide superior stability with
sedimentation during the 3 hours seen as free gasoil in top of the
samples.
[0112] The confocal laser scanning microscopy (CLSM) images of FIG.
4 taken just after emulsification did not show any major difference
and confirmed that the water droplets were at the same size as seen
by NMR.
[0113] Test 2--PGPR 90 and DIMODAN U/J at the amounts shown below
and at the total dosage shown below were mixed in MGO Shell
containing 33% or 50% water. The emulsifiers were added and
dissolved into the MGO at 40.degree. C. or 55.degree. C. and this
temperature was maintained during mixing with Ultra Turrax at 20500
rpm for 64 seconds. The results are shown in Table 2.
TABLE-US-00002 TABLE 2 PGPR + Temp Trial PGPR 90 % U/J % U/J %
Water % .degree. C. D50.0 .mu.m 11 0.3 0.3 A 0.6 50 40 5.2 12 0.075
0.525 B 0.6 50 40 4.7 13 0.5 0.5 A 1.0 33 55 11.3 14 0.125 0.875 B
1.0 33 55 9.8 15 0.3 0.3 A 0.6 50 55 5.2 16 0.075 0.525 B 0.6 50 55
4.5
[0114] FIG. 6 shows images of the samples of Table 2. For each
composition, images were recorded at 1, 2 and 3 hours after
mixing.
[0115] The droplet size distribution shows that high water content
results in smaller droplets. The larger droplets for sample 13 and
14 was also reflected in the CLSM images of FIG. 7, where samples
13 and 14 showed less smooth structure as compared to the rest of
the samples.
[0116] The rheology was controlled by temperature and water
content. FIG. 5 demonstrates that shear thinning was only noticed
at 55% water level and only at very low shear rates. Newtonian flow
was obtained already at approx. 100 l/s. There was no difference
between emulsifier mixtures A and B in respect to viscosity.
[0117] All publications mentioned in the above specification are
herein incorporated by reference. Various modifications and
variations of the described methods and system of the invention
will be apparent to those skilled in the art without departing from
the scope and spirit of the invention. Although the invention has
been described in connection with specific preferred embodiments,
it should be understood that the invention as claimed should not be
unduly limited to such specific embodiments. Indeed, various
modifications of the described modes for carrying out the invention
which are obvious to those skilled in chemistry or related fields
are intended to be within the scope of the following claims
* * * * *