Note: Descriptions are shown in the official language in which they were submitted.
CA 031894 2023-04-17
WO 2022/084281
PCT/EP2021/078885
- I -
USE OF A DIESEL FUEL COMPOSITION
Field of the Invention
The present invention relates to the use of a diesel
fuel composition comprising a biodiesel component for
providing certain benefits in an Exhaust Gas
Recirculation (EGR) system in a compression ignition
engine. In particular, the present invention relates to
the use of said diesel fuel composition for reducing the
build-up of deposits in an Exhaust Gas Recirculation
system in a compression ignition engine.
Background of the Invention
Exhaust Gas Recirculation (EGR) is a NOx emission
control technique applicable to a wide range of diesel
engines from light-, medium- and heavy-duty diesel
engines systems right up to two-stroke low-speed marine
engines. The configuration of an EGR system depends on
the required EGR rate and other demands of the particular
application. Most EGR systems include the following main
hardware components: one or more EGR control valves, one
or more EGR coolers, piping, flanges and gaskets.
It has been found that EGR systems have a tendency
to become fouled by deposits that build up on the various
EGR hardware components. This is a particular problem
with high pressure EGR systems. Deposits forming in the
system can cause increased NOx emissions and fuel
consumption and can cause the system to fail by jamming
the EGR valve or completing blocking the system in severe
cases. Oxidation catalysts and/or particulate filters
can be fitted before the EGR system to reduce
hydrocarbons and particulates from the exhaust gas which
cause EGR fouling, but this adds cost and complexity and
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 2 -
therefore isn't widely employed by manufacturers. In the
case of low pressure EGR, the DPF is situated between the
engine and the low pressure EGR system, therefore
deposits are not such a problem in these configurations.
It would therefore be desirable to provide a fuel
based solution that prevents the formation of deposits in
the first instance, and is applicable to all EGR systems,
irrespective of the equipment that the manufacturer has
employed.
Biodiesel in the form of fatty acid methyl esters
(FAME) is the most commonly used renewable fuel source in
compression ignition (diesel) engines. FAMEs are
typically derivable from biological sources and are
typically included to reduce the environmental impact of
the fuel production and consumption process or to improve
lubricity. Globally, there is a trend towards increasing
levels of FAME in diesel fuel, though this is capped in
some markets due to concerns around sustainability of
FAME feedstocks and for reasons of engine/vehicle
compatibility.
It has now been found that by using a diesel fuel
composition comprising a certain amount of biodiesel
component such as FAME, a surprising and hitherto
unrecognised reduction in the build-up of EGR deposits
can be achieved.
Summary of the Invention
According to the present invention there is provided
the use of a diesel fuel composition comprising 5 vol% or
greater of biodiesel for reducing the build-up of
deposits in an Exhaust Gas Recirculation (EGR) system of
a compression ignition internal combustion engine.
According to another aspect of the present invention
there is provided a method for reducing the build-up of
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 3 -
deposits in an Exhaust Gas Recirculation (EGR) system of
a compression ignition internal combustion engine, which
method comprises a step of introducing into said engine a
diesel fuel composition which comprises 5 vol% or greater
of biodiesel.
It has been found that use of a diesel fuel
composition comprising a certain amount of biodiesel
component can provide reduced build-up of deposits in the
EGR system of a compression ignition internal combustion
engine.
It has also been found that use of a diesel fuel
composition comprising a certain amount of biodiesel
component can prevent the formation of deposits in the
EGR system in the first place and is applicable to all
EGR systems, irrespective of the equipment that the
manufacturer has employed.
Brief Description of the Drawings
Figure 1 is a graphical representation of the EGR
deposit mass results set out in Table 2 below with
circular markers denoting individual test results and
diamond markers denoting mean results for each FAME fuel
content level tested in Example 1.
Figure 2 is a graphical representation of the mean
EGR deposit mass results set out in Table 2 below for
each FAME fuel content level tested in Example 1.
Figure 3 is a graphical representation of the mean
percentage reduction in EGR deposit mass set out in Table
2 below for each FAME level tested in Example 1 versus
BO.
Detailed Description of the Invention
As used herein there is provided the use of a diesel
fuel composition comprising 5 vol% or greater of
biodiesel for reducing the build-up of deposits in an
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 4 -
Exhaust Gas Recirculation (EGR) system of a compression
ignition internal combustion engine.
In the context of this aspect of the invention, the
term "reducing the build-up of deposits" embraces any
degree of reduction in the build-up of deposits. The
reduction in the build-up of deposits may be of the order
of 5% or more, preferably 10% or more, more preferably
20% or more, even more preferably 50% or more, and
especially 70% or more compared to the build-up of
deposits in an EGR system caused by an analogous fuel
formulation which does not contain a biodiesel component.
As used herein, the term "reducing the build-up" also
encompasses the prevention of EGR deposit formation in
the first place.
It has been found that the present invention is
particularly useful in the case of high pressure EGR
systems because these systems are more susceptible to
deposit build up than low pressure EGR systems.
It is also envisaged that the present invention may
be used for the purpose of clean-up of existing EGR
deposits formed with conventional diesel fuel.
A first essential component herein is a biodiesel
component. Biodiesel fuels are fuels which derive from
biological materials.
The biodiesel component is present in the diesel fuel
composition herein at a level of 5 %v/v or greater,
preferably 10% v/v or greater, more preferably in the
range from 10% v/v to 50% v/v, even more preferably in the
range from 10% v/v to 40% v/v, and especially from 20% v/v
to 40% v/v. In an especially preferred embodiment of the
present invention, the biodiesel component is present at a
level in the range from 20% v/v to 30% v/v, based on the
total diesel fuel composition.
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 5 -
Suitable biodiesel fuels for use herein include any
bio-derived oxygenate. Processing routes exist to derive
a variety of classes of oxygenates from biomaterial, these
include alcohols, ketones, phenols, ethers and esters,
such as alkyl esters, including, but not limited to methyl
and ethyl esters.
A preferred biodiesel component for use herein is a
fatty acid alkyl ester (FAAE). It is known to include
fatty acid alkyl esters (FAAEs), in particular fatty acid
methyl esters (FAMEs), in diesel fuel compositions,
although not in the context of reducing build-up of
deposits in EGR systems. Examples of suitable FAAEs
include rapeseed methyl ester (RME), palm oil methyl ester
(POME), soy methyl ester, sunflower oil methyl ester,
tallow methyl ester (TME), used cooking oil methyl ester
(UCOME), and the like. F.AAEs are typically derivable from
biological sources and are typically included to reduce
the environmental impact of the fuel production and
consumption process or to improve lubricity.
FAAEs, of which the most commonly used in the context
of diesel fuels are the methyl esters, are already known
as renewable diesel fuels (so-called 'biodiesel' fuels).
They contain long chain carboxylic acid molecules
(generally from 10 to 22 carbon atoms long), each having
an alcohol molecule attached to one end. Organically
derived oils such as vegetable oils (including recycled
vegetable oils) and animal fats (including fish oils) can
be subjected to a transesterification process with an
alcohol (typically a Ci to C5 alcohol) to form the
corresponding fatty esters, typically mono-alkylated.
This process, which is suitably either acid- or base-
catalysed, such as with the base KOH, converts the
triglycerides contained in the oils into fatty acid
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 6 -
components of the oils from their glycerol backbone.
FAAEs can also be prepared from used cooking oils, and can
be prepared by standard esterification from fatty acids.
In the present invention, the FAAE may be any
alkylated fatty acid or mixture of fatty acids. Its fatty
acid component(s) are preferably derived from a biological
source, more preferably a vegetable source. They may be
saturated or unsaturated. They may be linear or branched,
cyclic or polycyclic. Suitably, they will have from 6 to
30, preferably 10 to 30, more suitably from 10 to 22 or
from 12 to 24 or from 16 to 18, carbon atoms including the
acid group(s) A PAAE will typically comprise a
mixture of different fatty acid esters of different fatty
acid esters of different chain lengths, depending on its
source.
The FAAE used in the present invention is preferably
derived from a natural fatty oil, for instance tall oil,
rapeseed oil, palm oil or soy oil.
The FAAE is preferably a C1 to C5 alkyl ester, more
preferably a methyl, ethyl, propyl, (suitably iso-propyl)
or butyl ester, yet more preferably a methyl or ethyl
ester and in particular a methyl ester. In one embodiment
herein, the FAAE is selected from methyl ester of palm oil
(POME) and methyl ester of rapeseed oil (RME, and mixtures
thereof.
In general, it may be either natural or synthetic,
refined or unrefined ('crude').
The FAAE may contain impurities or by-products as a
result of the manufacturing process.
The FAAE suitably complies with specifications
applying to the rest of the fuel composition, and/or to
the base fuel to which it is added, bearing in mind the
intended use to which the composition is to be put (for
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 7 -
example, in which geographical area and at what time of
year). In particular, the FAAE preferably has a flash
point (IP 34) of greater than 101 C; a kinematic viscosity
at 40 C (IP 71) of 1.9 to 6.0 mm2/s, preferably 3.5 to 5.0
m2/s; a density of 845 to 910 kg/m3, preferably from 860
to 900 kg/m3, at 15 C (IP 365, EN ISO 12185 or EN ISO
3675); a water content (IP 386) of less than 500 ppm; a
195 (the temperature at which 95% of the fuel has
evaporated, measured according to IP 123) of less than
360 C; an acid number (IP 139) of less than 0.8mgKOH/g,
preferably less than 0.5mgKOH/g; and an iodine number (IP
84) of less than 125, preferably less than 120 or less
than 115, grams of iodine (12) per 110g of fuel. It also
preferably contains (e.g. by gas chromatography (GC)) less
than 0.2% w/w of free methanol, less than 0.02% w/w of
free glycerol and greater than 96.5% w/w esters. In
general it may be preferred for the FAAE to conform to the
European specification EN14214 for fatty methyl esters for
use as diesel fuels.
Two or more FAAEs may be added to the diesel fuel
composition in accordance with the present invention,
either separately or as a pre-prepared blend.
The FAAE is incorporated into the diesel fuel
composition typically as a blend (i.e. a physical mixture)
and optionally with one or more other fuel components
(such as diesel base fuels) and optionally with one or
more fuel additives. The FAAE is conveniently
incorporated into the diesel fuel composition before the
composition is introduced into the diesel engine which is
to be run on the fuel composition.
A preferred fuel component for use in the diesel fuel
composition herein, in addition to the FAAE, is a
paraffinic gasoil. The paraffinic gasoil suitable for use
CA 031894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 8 -
in the present invention can be derived from any suitable
source as long as it is suitable for use in a diesel fuel
composition.
Suitable paraffinic gasoils include, for example,
Fischer-Tropsch derived gasoils, and gasoils derived from
hydrotreated vegetable oil (HVO), and mixtures thereof.
A preferred paraffinic gasoil for use herein is a
Fischer-Tropsch derived gasoil fuel. The paraffinic
nature of Fischer-Tropsch derived gasoil means that
diesel fuel compositions containing it will have high
cetane numbers compared to conventional diesel.
While Fischer-Tropsch derived gasoil is a preferred
paraffinic gasoil for use herein, the term "paraffinic
gasoil" as used herein also includes those paraffinic
gasoils derived from the hydrotreating of vegetable oils
(HVO). The HVO process is based on an oil refining
technology. In the process, hydrogen is used to remove
oxygen from the triglyceride vegetable oil molecules and
to split the triglyceride into three separate chains thus
creating paraffinic hydrocarbons.
When present, the paraffinic gasoil (i.e. the
Fischer-Tropsch derived gasoil, the hydrogenated vegetable
oil derived gasoil) will preferably consist of at least
95% w/w, more preferably at least 98% w/w, even more
preferably at least 99.5% w/w, and most preferably up to
100% w/w of paraffinic components, preferably iso- and
normal paraffins.
By "Fischer-Tropsch derived" is meant that a fuel or
base oil is, or derives from, a synthesis product of a
Fischer-Tropsch condensation process. The term "non-
Fischer-Tropsch derived" may be interpreted accordingly.
A Fischer-Tropsch derived fuel may also be referred to as
a GTL (gas-to-liquid) fuel.
CA 03198894 2023-04-17
WO 2022/084281
PCT/EP2021/078885
- 9 -
The Fischer-Tropsch reaction converts carbon
monoxide and hydrogen into longer chain, usually
paraffinic, hydrocarbons:
n(CO + 2H2) = (-CH2-), + nH20 + heat, in the presence of
an appropriate catalyst and typically at elevated
temperatures (e.g. 125 to 300 C, preferably 175 to 250 C)
and/or pressures (e.g. 5 to 100 bar, preferably 12 to 50
bar). Hydrogen: carbon monoxide ratios other than 2:1
may be employed if desired.
The carbon monoxide and hydrogen may themselves be
derived from organic or inorganic, natural or synthetic
sources, typically either from natural gas or from
organically derived methane. More recently routes to
derive this syngas carbon monoxide from carbon dioxide
are being tried in order to obtain greenhouse gas
benefits.
Gas oil, kerosene fuel and base oil products may be
obtained directly from the Fischer-Tropsch reaction, or
indirectly for instance by fractionation of Fischer-
Tropsch synthesis products or from hydrotreated Fischer-
Tropsch synthesis products. Hydrotreatment can involve
hydrocracking to adjust the boiling range (see, e. g.
GB2077289 and EP0147873) and/or hydroisomerisation which
can improve cold flow properties by increasing the
proportion of branched paraffins. EP0583836 describes a
two-step hydrotreatment process in which a Fischer-
Tropsch synthesis product is firstly subjected to
hydroconversion under conditions such that it undergoes
substantially no isomerisation or hydrocracking (this
hydrogenates the olefinic and oxygen-containing
components), and then at least part of the resultant
product is hydroconverted under conditions such that
hydrocracking and isomerisation occur to yield a
CA 031894 2023-04-17
WO 2022/084281
PCT/EP2021/078885
- 10 -
substantially paraffinic hydrocarbon fuel or oil.
Desired diesel fuel fraction(s) may subsequently be
isolated for instance by distillation.
Other post-synthesis treatments, such as
polymerisation, alkylation, distillation, cracking-
decarboxylation, isomerisation and hydroreforming, may be
employed to modify the properties of Fischer-Tropsch
condensation products, as described for instance in US-A-
4125566 and US-A-4478955.
Typical catalysts for the Fischer-Tropsch synthesis
of paraffinic hydrocarbons comprise, as the catalytically
active component, a metal from Group VIII of the periodic
table, in particular ruthenium, iron, cobalt or nickel.
Suitable such catalysts are described for instance in
EP0583836.
An example of a Fischer-Tropsch based process is the
SMDS (Shell Middle Distillate Synthesis) described in
The Shell Middle Distillate Synthesis Process", van der
Burgt et al (vide supra). This process (also sometimes
referred to as the Shell "Gas-to-Liquids" or "GTL"
technology) produces diesel range products by conversion
of a natural gas (primarily methane) derived synthesis
gas into a heavy long-chain hydrocarbon (paraffin) wax
which can then be hydroconverted and fractionated to
produce liquid transport fuels such as gasoils and
kerosene. Versions of the SMDS process, utilising fixed-
bed reactors for the catalytic conversion step, are
currently in use in Bintulu, Malaysia, and in Pearl GTL,
Ras Laffan, Qatar. Kerosenes and (gas)oils prepared by
the SMDS process are commercially available for instance
from the Royal Dutch/Shell Group of Companies.
By virtue of the Fischer-Tropsch process, a Fischer-
Tropsch derived gasoil has essentially no, or
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 11 -
undetectable levels of, sulphur and nitrogen. Compounds
containing these heteroatoms tend to act as poisons for
Fischer-Tropsch catalysts and are therefore removed from
the synthesis gas feed. Further, the process as usually
operated produces no or virtually no aromatic components.
For example, the aromatics content of a Fischer-
Tropsch gasoil, as determined for instance by ASTM D4629,
will typically be below 1% w/w, preferably below 0.5% w/w
and more preferably below 0.1% w/w.
Generally speaking, Fischer-Tropsch derived fuels
have relatively low levels of polar components, in
particular polar surfactants, for instance compared to
petroleum derived fuels. It is believed that this can
contribute to improved antifoaming and dehazing
performance. Such polar components may include for
example oxygenates, and sulphur and nitrogen containing
compounds. A low level of sulphur in a Fischer-Tropsch
derived fuel is generally indicative of low levels of
both oxygenates and nitrogen-containing compounds, since
all are removed by the same treatment processes.
A preferred Fischer-Tropsch derived gasoil fuel for
use herein is a liquid hydrocarbon middle distillate fuel
with a distillation range similar to that of a petroleum
derived diesel, that is typically within the 160 C to
400 C range, preferably with a 195 of 360 C or less.
Again, Fischer-Tropsch derived fuels tend to be low in
undesirable fuel components such as sulphur, nitrogen and
aromatics.
A preferred Fischer-Tropsch derived gasoil fuel will
typically have a density (as measured by EN ISO 12185) of
from 0.76 to 0.80, preferably from 0.77 to 0.79, more
preferably from 0.775 to 0.785 g/cm3 at 15 C.
A preferred Fischer-Tropsch derived gasoil fuel for
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 12 -
use herein has a cetane number (ASTM D613) of greater
than 70, suitably from 70 to 85, most suitably from 70 to
77.
A preferred Fischer-Tropsch derived gasoil fuel for
use herein has a kinematic viscosity at 40 C (as measured
according to ASTM D445) in the range from 2.0 mm2/s to 5.0
mm2/s, preferably from 2.5 mm2/s to 4.0 mm2/s.
A preferred Fischer-Tropsch derived gasoil for use
herein has a sulphur content (ASTM D2622) of 5 ppmw (parts
per million by weight) or less, preferably of 2 ppmw or
less.
A preferred Fischer-Tropsch derived gasoil fuel for
use in the present invention is that produced as a
distinct finished product, that is suitable for sale and
used in applications that require the particular
characteristics of a gasoil fuel. In particular, it
exhibits a distillation range falling within the range
normally relating to Fischer-Tropsch derived gasoil
fuels, as set out above.
A fuel composition used in the present invention may
include a mixture of two or more Fisher-Tropsch derived
gasoil fuels.
When present, the Fischer-Tropsch derived components
used herein (i.e. the Fischer-Tropsch derived gasoil) will
preferably comprise no more than 3% w/w, more preferably
no more than 2% w/w, even more preferably no more than 1%
w/w of cycloparaffins (naphthenes), by weight of the
Fischer-Tropsch derived component.
When present, the Fischer-Tropsch derived components
used herein (i.e. the Fischer-Tropsch derived gasoil)
preferably comprise no more than 1% w/w, more preferably
no more than 0.5% w/w, of olefins, by weight of the
Fischer-Tropsch derived component.
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 13 -
The diesel fuel compositions described herein for
use in the present invention are particularly suitable
for use as a diesel fuel, and can be used for arctic
applications, as winter grade diesel fuel due to the
excellent cold flow properties.
For example, a cloud point of -10 C or lower (EN
23015) or a cold filter plugging point (CFPP) of -20 C or
lower (as measured by EN 116) may be possible with fuel
compositions herein.
The diesel fuel compositions described herein may
comprise a diesel base fuel in addition to a biodiesel
fuel component.
The diesel base fuel may be any petroleum derived
diesel suitable for use in an internal combustion engine,
such as a petroleum derived low sulphur diesel comprising
<50 ppm of sulphur, for example, an ultra-low sulphur
diesel (ULSD) or a zero sulphur diesel (ZSD).
Preferably, the low sulphur diesel comprises <10 ppm of
sulphur.
The petroleum derived low sulphur diesel preferred
for use in the present invention will typically have a
density from 0.78 to 0.865, preferably from 0.80 to 0.845
g/cm3, at 15 C; a cetane number (ASTM D613) at least 51;
and a kinematic viscosity (ASTM D445) from 1.5 to 4.5,
preferably 2.0 to 4.0, more preferably from 2.2 to 3.7
mm2/s at 40 C.
In one embodiment, the diesel base fuel is a
conventional petroleum-derived diesel.
Generally speaking, in the context of the present
invention the fuel composition may be additivated with
fuel additives.
It has been found by the present inventors that it
is particularly advantageous to include a deposit control
CA 031894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 14 -
additive (DCA) package in the diesel fuel composition in
addition to the biodiesel component from the viewpoint of
reducing build-up of deposits in the EGR system.
Unless otherwise stated, the (active matter)
concentration of each such additive in a fuel composition
is preferably up to 10000 ppmw, more preferably in the
range from 5 to 1000 ppmw, advantageously from 75 to 300
ppmw, such as from 95 to 150 ppmw. Such additives may be
added at various stages during the production of a fuel
composition; those added to a base fuel at the refinery
for example might be selected from anti-static agents,
pipeline drag reducers, middle distillate flow improvers
(MDFI) (e.g., ethylene/vinyl acetate copolymers or
acrylate/maleic anhydride copolymers), lubricity
enhancers, anti-oxidants and wax anti-settling agents.
The fuel composition may include a DCA, by which is
meant an agent (suitably a surfactant) which can act to
remove, and/or to prevent the build-up of, combustion
related deposits within an engine, in particular in the
fuel injection system such as in the injector nozzles.
Such materials are sometimes referred to as dispersant
additives. Where the fuel composition includes a DCA,
preferred concentrations are in the range 20 to 500 ppmw
active matter detergent based on the overall fuel
composition, more preferably 40 to 500 ppmw, most
preferably 40 to 300 ppmw or 100 to 300 ppmw or 150 to
300 ppmw. DCAs for diesel fuel are known and
commercially available. Examples of suitable DCA
additives include polyolefin substituted succinimides or
succinamides of polyamines, for instance polyisobutylene
succinimides or polyisobutylene amine succinamides,
aliphatic amines, Mannich bases or amines and polyolefin
(e.g. polyisobutylene) maleic anhydrides. Particularly
CA 031894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 15 -
preferred are polyolefin substituted succinimides such as
polyisobutylene succinimides.
Other components which may be incorporated as fuel
additives, for instance in combination with a detergent,
include lubricity enhancers; dehazers, e.g. alkoxylated
phenol formaldehyde polymers; anti-foaming agents (e.g.
commercially available polyether-modified polysiloxanes);
ignition improvers (cetane improvers) (e.g. 2-ethylhexyl
nitrate (EHN), cyclohexyl nitrate, di-tert-butyl peroxide
and those disclosed in US4208190 at column 2, line 27 to
column 3, line 21); anti-rust agents (e.g. a propane-1,2-
diol semi-ester of tetrapropenyl succinic acid, or
polyhydric alcohol esters of a succinic acid derivative,
the succinic acid derivative having on at least one of
its alpha-carbon atoms an unsubstituted or substituted
aliphatic hydrocarbon group containing from 20 to 500
carbon atoms, e.g. the pentaerythritol diester of
polyisobutylene-substituted succinic acid); corrosion
inhibitors; reodorants; anti-wear additives; anti-
oxidants (e.g. phenolics such as 2,6-di-tert-butylphenol,
or phenylenediamines such as N,N'-di-sec-butyl-p-
phenylenediamine); metal deactivators; static dissipator
additives; and mixtures thereof.
It is preferred that the additive contain an anti-
foaming agent, more preferably in combination with an
anti-rust agent and/or a corrosion inhibitor and/or a
lubricity additive.
It is particularly preferred that a lubricity
enhancer be included in the fuel composition, especially
when it has a low (e.g. 500 ppmw or less) sulfur content.
The lubricity enhancer is conveniently present at a
concentration from 50 to 1000 ppmw, preferably from 100
to 1000 ppmw, based on the overall fuel composition.
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 16 -
The (active matter) concentration of any dehazer in
the fuel composition will preferably be in the range from
1 to 20 ppmw, more preferably from 1 to 15 ppmw, still
more preferably from 1 to 10 ppmw and advantageously from
1 to 5 ppmw. The (active matter) concentration of any
ignition improver present will preferably be 600 ppmw or
less, more preferably 500 ppmw or less, conveniently from
300 to 500 ppmw.
The present invention may in particular be
applicable where the fuel composition is used or intended
to be used in a direct injection diesel engine, for
example of the rotary pump, in-line pump, unit pump,
electronic unit injector or common rail type, or in an
indirect injection diesel engine. The fuel composition
may be suitable for use in heavy-and/or light-duty diesel
engines, and in engines designed for on-road use or off-
road use.
In order to be suitable for at least the above uses,
the diesel fuel composition of the present invention
preferably has one or more of the following
characteristics:
-a kinematic viscosity at 40 C of 1.9 mm2/s or greater,
more preferably in the range from 1.9 to 4.5 mm2/s;
-a density of 800 kg/m3 or greater, more preferably in
the range from 800 to 860, even more preferably 800 to
845 kg/m3;
-a T95 of 360 C or less;
-a cloud point in the range from 0 C to -13 C, more
preferably from -5 C to -8 C;
-a CFPP in the range of from -8 C to -30 C, more
preferably from -15 C to -20 C.
The invention is illustrated by the following non-
limiting examples.
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 17 -
Examples
Example 1
Four different fuels were used in the examples
herein.
One fuel was a conventional diesel fuel, CEC RF79-07
(Diesel BO). The physical characteristics of the
conventional diesel fuel (Diesel BO) used in the examples
is shown in Table 1 below. As used herein "Diesel BO"
means diesel base fuel containing zero biofuel
components. The biofuel component was Palm Oil Methyl
Ester - POME.
The second, third and fourth test fuels were diesel
fuel compositions designed to contain 10, 20, or 30%
biofuel component. In fact, with normal experimental
errors, the actual bio-contents of the fuels were 10.5,
20.6 and 29.9%, respectively. The base diesel fuel to
which the biofuel was added was diesel fuel complying
with the EN590 diesel fuel specification and is a
reference fuel designated CEC RF79-07. Again, the
biofuel component was a POME FAME component. The
analysed properties of the diesel and FAME blends B10,
B20, B30 fuel used in the examples is shown in Table 1
below.
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
Table 1: Test Fuel Parameter Measurements and Test Methods
Test Parameter Test Method Unit Result -
Result - Result - Result
BO B10 B20 -
B30
Appearance Visual C&B C&B C&B C&B
Cetane Number EN ISO 5165 53.1 53.6 54.1 55.8
Cetane Index EN I 4264 55.1 54.9 54.8
Density @ 15 C EN IT 1-185 Kg/L 835.1 839.0 842.8
846.9
Cloud Point EN I 3015 C -12 -4 0
CFPP EN 11= C -22 -16 -6 -1
Carbon Residue (10% EN Thu 10370 % <0.10
Dis. Res.) m/m
Flash Point EN ISO 2719 C 88.0 88.0 90.0 93.0
Lubricity, wear scar EN ISO 12156-1 pm 324 191 184 191
I diameter @ 60 C
Sulfur EN ISO 20846 mg/kg <1.0 <5 <5 <5
1-
m
Viscosity @ 40 C EN ISO 3104 mp2/s 2.875 2.991 3.098 3.237
1
Water Content EN ISO 12937 n /kg 30 113 117 111
FAME Content EN 14078 'v 0 10.5 20.6 29.9
Mono Aromatics IP 391 mod a/m 18.1 16.2 14.1 12.2
Content
Polycyclic Aromatics IP 391 mod %m/m 4.2 3.9 3.4
3.0
Content
Total Aromatics IP 391 mod %m/m 22.3 20.1 17.5 15.2
Oxidation Stability EN 15751 h 48.0 36.5 30.0
Oxidation Stability EN ISO 12205 g/m3 <1 1 1 1
(1= -1)
A--1 (---i'ent EN ISO 6245 %m/m <0.001 <0.001 <0.001
<0.001
corrosion (3h EN ISO 2160 Rating 1A 1A 1A 1A
at 50 C)
Total Contamination EN 12662 Mg/kg 3 2 2
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
Carn ASTM D3343 mod %m/m 86.36
H 11 gen ASTM D3343 mod %m/m 13.64
EN 14078 %m/m 0
G _ Calorific Value ASTM D3338 mod MJ/kg
t Calorific Value ASTM D3338 MJ/kg 43.18
Distillation
(Evaporated)
E250 EN L 3405 %v/v 26.8 21.8 17.9
E350 EN I 3405 %v/v 97.5
IBP EN I 3405 C 203.2 206.0 201.1 206.0
95%v EN I 3405 C 347.8 345.1 336.5 339.7
FBP EN Thu 3405 C 362.8 352.5 347.0 345.5
1
1-
w
1
CA 03198894 2023-04-17
WO 2022/084281
PCT/EP2021/078885
- 20 -
Test Method
The engine used in the examples was a standard
configuration PSA DV6 1.6L Euro 5 engine of a type
installed in several light-duty passenger car models in
Europe. A clean EGR system was weighed, then fitted to
the engine.
The test was run for 24 hours continuously, at 2500
rpm and 5kW (19Nm) test condition. The engine coolant
temperature was controlled to 37 C for the entire test
duration. When the test was completed, the engine was
dismantled, and all EGR components weighed. All EGR
components were then photographed, before the entire EGR
system was cleaned using solvents and a sonic bath, to
remove the deposits. The clean EGR system was then
reweighed before being fitted to the engine to run the
next test. A sequence of tests was run which was
designed to avoid back to back repeats on any fuel,
except for two tests on BO at the start of the sequence
which were run to ensure an acceptable level of
repeatability. The remaining repeats on each fuel were
distributed throughout the test sequence to result in a
balanced test order. Four tests were run with BO fuel
and two tests on each of B10, B20 and B30. The test
sequence and EGR deposit mass results are given in Table
2 below and the results are displayed in Figures 1-3.
Table 2: Fuel Testing Sequence and EGR Deposit Mass
Results
Test * Test Fuel EGR Deposit Mass
(grams)
1 BO 18.53
2 BO 19.03
3 B20 13.56
4 B30 13.01
5 B10 14.12
6 BO 18.36
7 B10 15.32
CA 03198894 2023-04-17
WO 2022/084281 PCT/EP2021/078885
- 21 -
8 B20 13.91
9 B30 13.84
BO 19.55
Mean result BO 18.87
Mean result B10 14.72
Mean result B20 13.73
Mean result B30 13.42
Mean reduction
relative to BO
/0 )
Mean reduction B10 22.0
Mean reduction B20 27.2
Mean reduction B30 28.8
Discussion
As can be seen from the results in Table 2 and the
graphs in Figures 1-3, there is a significant reduction
in the amount of deposits formed on the EGR components in
5 the case of the FAME-containing fuels compared with the
conventional diesel BO fuel and the reduction increases
with increasing FAME level. A 22.0% lower deposit mass
formed on the EGR components in the case of B10 diesel
fuel compared with the BO diesel fuel. In the case of
10 the B20 fuel the difference from BO was 27.2% and in the
case of the B30 fuel the difference from BO was 28.8%.
