(19)
(11)EP 3 502 216 A1

(12)EUROPEAN PATENT APPLICATION

(43)Date of publication:
26.06.2019 Bulletin 2019/26

(21)Application number: 17306886.7

(22)Date of filing:  21.12.2017
(51)International Patent Classification (IPC): 
C10L 1/16(2006.01)
(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME
Designated Validation States:
MA MD TN

(71)Applicants:
  • Global Bioenergies
    91000 Evry (FR)
  • Global Bioenergies GmbH
    06237 Leuna (DE)

(72)Inventors:
  • ROCLE, Ronan
    94700 MAISONS ALFORT (FR)
  • BULC, Ales
    04229 LEIPZIG (DE)

(74)Representative: Lavoix 
2, place d'Estienne d'Orves
75441 Paris Cedex 09
75441 Paris Cedex 09 (FR)

  


(54)GASOLINE COMPOSITION ENABLING REDUCED PARTICULATE EMISSIONS


(57) The present invention relates to the use of isooctane optionally in combination with oxygenate in gasoline composition to reduce the particulate emissions. The present invention also relates to the gasoline composition comprising isooctane and optionally oxygenates.




Description


[0001] The present invention relates to gasoline composition especially to gasoline composition suitable as automobile fuels and associated with low particulate emissions, the present invention also relates to the use of isooctane in gasoline composition to reduce particulate emissions.

[0002] On-road vehicles are an important source of particulate matter emissions. Especially, particulate matter emissions from motor vehicles are of particular importance in urban areas where emissions occur in close proximity to populations. Once inhaled, these particles can affect the heart and lungs and cause serious health effects.

[0003] Particulates are generated in the combustion chamber and then emitted through the exhaust system. Norm Euro6C of the European Union requires that gasoline engines emit less than 4.5 mg/km of particulate matter in mass and less than 6.1011 per km in number. Reducing particulate emissions is thus of great interest.

[0004] The reduction of the particulate emission can be addressed by the engine-fuel system or through the exhaust system. Three ways of reducing particulate matter emissions are available:
  1. (i) Engine design;
  2. (ii) Fuel composition;
  3. (iii) Exhaust system (depollution).


[0005] Up to now, developments have been mainly concentrated on engine design and depollution at the exhaust system (catalytic conversion, particulate filters, etc).

[0006] There is thus a need to develop new fuel composition enabling to reduce particulate emissions.

[0007] It is known, especially from EP2568033 and Westphal et al, Toxicology, 2010, 268, 198-203, that oxygenate compounds (for example ethyl tertiary butyl ether (ETBE)) can be used in gasoline compositions to reduce particulate emissions. However, the addition of oxygenates in gasoline is limited due to the oxygen limit of 3.7% in mass fixed by EN228 norm. Moreover, the conventional spark-ignited cars are not compatible with high amounts of oxygen. Therefore, the maximum reduction in particulate matter emissions in mass and in number which can be achieved by this method is limited.

[0008] There is thus a need to find alternative solutions to the use of oxygenates and to find new compounds enabling to reduce particulate emissions when added in gasoline composition.

[0009] A second challenge is also to obtain the maximum reduction of particulate emissions while achieving the highest greenhouse gases emissions reduction in terms of CO2 equivalents through the incorporation of a maximum amount of biobased gasoline components.

[0010] An object of the invention is thus to provide gasoline composition enabling to reduce particulate emissions.

[0011] Another objective of the invention is to provide such gasoline composition comprising a maximum amount of biobased components.

[0012] Another objective of the invention is also to provide gasoline composition in conformation with norm Euro6C (2009) and EN228 (2008).

[0013] Other objectives will be disclosed in the description of the invention which follows.

[0014] These objectives are obtained by the present invention which relates to a gasoline composition comprising hydrocarbons mixture with 6 to 100%, preferably 6 to 99.5%, by volume of isooctane and from 0 to 94% by volume of compound comprising oxygen.

[0015] Preferably, the gasoline composition of the invention comprises from 6 to 40%, preferably from 6 to 35%, and more preferably from 6 to 30% by volume of isooctane.

[0016] Preferably, the isooctane is biobased. A biobased isooctane can be obtained by dimerization of a biobased isobutene followed by hydrogenation. Dimerization of isobutene followed by hydrogenation is a well-known process, described for example by Treese at al., "Handbook of Petroleum Processing", Springer, 2015. The biobased isobutene can be produced by direct fermentation for example according to the process disclosed in WO2017085167 or WO2016042012, or even in the following documents: WO2016042011, WO2017162738, WO2010001078, WO2012052427, WO2014064198, WO2015082447, WO2011032934, WO2015101493, WO2014001517, WO2015004211, WO2017017124.

[0017] According to the present invention, "biobased compounds" refers to compounds obtained from bioresources for example by use of renewable resources (such as agricultural resources). A compound is considered fully biobased when it is produced using only renewable resources. A compound is considered partially biobased when it is produced from compounds issued from renewables resources and compounds which are not issued from renewable resources. The biobased content can be tested using ASTM D6866 - 16 (Standard test methods for determining the biobased content of solid, liquid, and gaseous samples using radiocarbon analysis).

[0018] The compounds comprising oxygen can also be named oxygenates, there are organic compounds (i.e. compounds comprising carbon and hydrogen) comprising at least one oxygen atom. In the present invention, any oxygenate that increases the weight percentage of oxygen in the gasoline composition can be used. Oxygenates are generally combustible liquids comprising carbon, hydrogen and oxygen. Preferably, oxygenates are chosen among alcohol or ether compounds. Preferably, oxygenates are chosen among lower alcohols such as ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, isoamyl alcohol, isoprenol, prenol or among tertiary alkyl ether such as ethyl tertiary butyl ether (ETBE), methyl tertiary butyl ether (MTBE), ethanol, tertiary-amyl methyl ether (TAME) or mixtures thereof. Preferably, the oxygenate is ETBE.

[0019] The composition of the invention can comprise combination of different oxygenates.

[0020] Preferably, in the composition according to the invention, the oxygenate, or the combination of oxygenates, is present in an amount comprised between 0 and 94% by volume, preferably between 0 and 30% by volume, more preferably between 10 and 30% by volume.

[0021] Preferably, oxygenates used in the compound according to the invention are totally or partially biobased oxygenates, for example ethanol from bioressources (also called bioethanol), ether obtained by etherification between an alcohol from bioressources and alkanes from bioressources. For example, ETBE can be obtained by etherification of ethanol obtained from bioressources and isobutene obtained from bioressources for example according to the process disclosed above.

[0022] In the present invention, the following expressions have the following definitions:

"Particulate matter", or "particulate" or "particle": a complex mixture of extremely small particles and liquid droplets that get into the air. These particles are composed of a carbon core upon which high-molecular weight organic chemical components and heavy metals deposit.

"Research Octane Number" (RON) : the octane number of a fuel determined by running the fuel through a specific test engine with a variable compression ratio under controlled conditions, and comparing these results with those for mixtures of isooctane and n-heptane. RON can be measured according to ASTM D 2699.

"Motor Octane Number" (MON) : the octane number of a fuel determined by running the fuel through a similar test engine to the one used in RON but with a preheated fuel mixture, a higher engine speed and variable ignition timing to further stress the fuel's knock resistance. Depending on the composition of the fuel, the MON of a modern gasoline is generally about 8 to 10 points lower than the RON. MON can be measured according to ASTM D2700.

"Vapor pressure" or "Reid vapor pressure" of a gasoline is a measure of the vapor pressure of the gasoline in pounds per square inch at 1000 °F (537,8°C). It is an indication of the volatility of the gasoline. Reid vapor pressure of a gasoline can be measured according to ASTM D5191.

"Petroleum based fuel" means a fuel that includes a fractional distillate of petroleum.

"Fuel additive" refers to chemical components added to fuels to alter the properties of the fuel, e.g. to improve engine performance, fuel handling, fuel stability or for contaminant control. Types of additives include, but are not limited to, antioxidants, thermal stability improvers, cetane improvers, stabilizers, cold flow improvers, combustion improvers, antifoams, anti-haze additives, corrosion inhibitors, lubricity improvers, icing inhibitors, injector cleanliness additives, smoke suppressants, drag reducing additives, metal deactivators, dispersants, detergents, demulsifiers, dyes, markers, static dissipaters, biocides and combinations thereof.



[0023] In the description, all numbers disclosed herein are approximate values, regardless whether the word "about" or "approximate" is used in connection therewith.
In the description, the range from xxx to yyy, without any other information, includes the values xxx and xxx.

[0024] The gasoline composition according to the invention is any petroleum-derived composition comprising organic compounds generally obtained by the fractional distillation of petroleum. The gasoline composition of the invention can be a conventional mix of alkanes straight chain, branched and cyclic, comprising from 5 to 12 carbon atoms, with 6 to 100%, preferably 6 to 99.5%, by volume of isooctane, preferably from 6 to 40%, more preferably from 6 to 35% by volume of isooctane, along with some aromatic compounds. Preferably, the maximum concentration of aromatics in the gasoline composition is 35% by volume. Preferably, the gasoline composition has properties complying to EN228 norm or can be blended with an additional component, such as an oxygenate, and the resulting blend is compliant to the EN228 norm.

[0025] The present invention also relates to the use of isooctane as a gasoline composition or in a gasoline composition to reduce particulate emissions.

[0026] The present invention also relates to the use of 6 to 100 vol%, preferably 6 to 99.5 vol%, preferably 6 to 40 vol%, more preferably 6 to 35 vol%, of isooctane together with 0 to 96 vol%, preferably 0 to 30 vol%, of oxygenates, in a gasoline composition to reduce the particulate emissions.

[0027] The gasoline composition, the isooctane and the oxygenates are as disclosed above.

[0028] The present invention also relates to a method for reducing the particulate emissions of an engine car comprising the use of isooctanol as gasoline composition or in a gasoline composition. Preferably, the isooctane is used in a proportion from 6 to 100% by volume, preferably from 6 to 99.5% by volume, for example from 6 to 40% by volume, more preferably from 6 to 35% by volume.

[0029] The present invention also relates to a method for reducing the particulate emissions of an engine car comprising the use of a gasoline composition comprising from 6 to 100% by volume, preferably from 6 to 99.5% by volume, for example from 6 to 40% by volume, more preferably from 6 to 35% by volume, of isooctane and from 0 to 96%, preferably 0 to 30 %, by volume of oxygenates.

[0030] The present invention also relates to a method for reducing the particulate emissions of an engine car comprising the use of a gasoline composition according to the invention and as disclosed above.

[0031] The use of isooctane or of a combination of isooctane and oxygenates enables a huge reduction of the particulate emissions, especially a reduction up to 99% in mass, preferably up to 83% in mass, compared with a gasoline composition without such additives, of the particulate emissions.

[0032] The use of isooctane or of a combination of isooctane and oxygenates enables a huge reduction of the particulate emissions, especially a reduction up to 80%, preferably up to 45%, in number compared with a gasoline composition without such additives, of the particulate emissions.

Figure 1 represents the particle number in function to the particle size emitted by the use of different gasoline composition.

Figure 2 represents the particle mass in function to the particle size emitted by the use of different gasoline composition.

Figure 3 represents the number and mass of particles emitted by the use of different gasoline composition.

Figure 4 represents the particle number in function to the particle size emitted by the use of different gasoline composition.

Figure 5 represents the particle mass in function to the particle size emitted by the use of different gasoline composition.

Figure 6 represents the number and mass of particles emitted by the use of different gasoline composition.



[0033] The present invention will now be described thanks to the following non-limiting examples.

[0034] Tests were carried out in a one-cylinder engine such as descried above. All equipment used for the measures meets the specification of the DIN EN 228 norm.

1. Description of the gasoline composition used in the tests



[0035] The tests have been carried out on:
  • a base fuel composition from a refinery having a RON of 91 and no ethanol (named "Base fuel RON91E0");
  • a reference fuel composition sold at the pump in the European Union having a RON of 95 and 10 vol% of ethanol (named "reference fuel RON95E10). This composition complies with EN228;
  • a blend A comprising RON91E0 and 19,4 vol% of ETBE;
  • a blend B comprising RON91E0, 19.5 vol% of ETBE and 14.6 vol% isooctane;
  • a blend C comprising RON91E0 and 9.6 vol% isooctane; and
  • a blend D comprising RON91E0 and 29.1 vol% isooctane.


[0036] The compositions of the different fuel composition are given in table 1 below.
Table 1
 Composition in vol%
BlendIsooctaneETBERON91E0
Blend A 0 19.4 80.6
Blend B 14.6 19.5 65.9
Blend C 9.6   90.4
Blend D 29.1   70.9


[0037] The base fuel RON91E0 comprises 4.7 vol% of isooctane.

[0038] The different composition were analyzed with respect to DIN EN 228, the results are given in table 2 below.
Table 2
Fuel properties (unit)Base fuel RON91E0RON95E10Blend ABlend BBlend CBlend D
Density at 15°c (kg/m3) 730.2 748.4 734.1 729.1 727.6 727.2
% vaporized at 70°C (vol%) 34.1 48.7 32.4 22.2 38.2 13.9
% vaporized at 70°C (vol%) 62.2 58.6 70.6 69.8 64.9 59.7
Final boiling point (°C) 189 195.5 184.8 182.2 188.9 182.9
Vapor pressure DVPE, 37.8°C (KPa) 47.4 56.4 48.8 44.2 44.9 38.8
Oxygen content (% m/m) 0.0 3.63 3.15 3.28 <0.01 <0.01
Ethanol (about 1.6% in ETBE) (% vol/vol) 0.0 9.8 0.2 0.4 0 0
ETBE (% vol/vol) 0.0 0.1 19.4 19.5 0 0
Isooctane (% vol/vol) about 4.7 about 4.7 about 4.7 about 18.3 about 14.8 about 33.1
RON/MON 91/84 96.2/85.1 97.5/88.7 98.9/90.5 92.8/85.7 94.1/88.4

2. Engine tests



[0039] The tests were carried out on a single cylinder engine. The configuration parameters are given in table 3 below. A pre-optimization of engine parameters in proposed engine load points was performed with the RON95E10composition. The composition ratio was chosen to be 10.8, at upper level of series production engines, which enables a good evaluation of knock tendency.
Table 3 - engine configuration
 UnitValue
Bore mm 75
Stroke mm 90.5
Displacement cm3 400
Max. cylinder peak pressure bar 170
Compression ratio 1 10.8
Inlet and exhaust CVVT °CA 55
Intake/exhaust event length (1 mm) °CA 186
Direct injection (central, solenoid)   6-hole
bar 200
cm3/s 13.5


[0040] The engine tests performed were catalyst heating. Intention of catalyst heating load point is to increase exhaust temperature/heat flow at cold engine operation: fast light-off of three-way-catalyst (TWC). Catalyst heating load point was selected for fuel comparison due to its challenging boundary conditions for mixture formation, combustion and particulate emissions. Double injection (2nd ignition coupled injection) was investigated. For ignition coupled injection (5°CA after spark timing) is initiated. 2nd injection results in a stabilizing diffusive combustion allowing for later combustion at same combustion facility.

[0041] Table 4 below gives the parameters for catalyst heating tests.
Table 4
 UnitValue
nENG min-1 1200
IMEP bar 3
Compression ratio   10.76
EVC ° CA BTDC 10
IVO ° CA ATDC 10
PFuel bar 200
SOI Main ° CA BTDC 250
SOI Ignition ° CA ST+5
Air compression ratio   1.05
Toil °C 30
Tcoolant °C 30
Tintake °C 25
Spark Timing (ST) ° CA BTDC -15
nENG refers to the engine speed expressed in rotations per minute.
IMEP, indicated mean effective pressure, is the mean effective pressure calculated with indicated power. The mean effective pressure can be regarded as an average pressure in the cylinder for a complete engine cycle.
EVC refers to exhaust valve closing.
IVO refers to inlet valve opening.
SOI refers to start of injection.
°CA refers to the Crank angle.


[0042] The top dead centre (TDC) is the position of a piston in which it is farthest from the crankshaft. °CA BTDC refers to Crank angle before top dead center. °CA ATDC refers to Crank angle after top dead center.

[0043] The results of these tests are presented in figures 1 to 6.

[0044] Figures 4 to 6 enables to show the particle emissions reduction in mass and number depending on isooctane incorporation. Blend C show a reduction of particle emissions of 21% in mass and 13% in number compared to the base fuel RON91E0. Blend D (higher amount of isooctane) show a reduction of particle emissions of 83% in mass and 45% in number compared to the base fuel RON91E0.
These figures thus show that the addition of isooctane in a fuel composition enables a reduction of the particulate emissions.
Figures 1 to 3 enables to show the particle emissions reduction in mass and number of gasoline composition in which oxygenates (ETBE) and isooctane are added. The addition of both isooctane and oxygenate (ETBE) enables to reduce the particulate emissions by 83% in mass and 45% in number.

[0045] The results thus show that isooctane enables to reduce particulate emissions which thus enables to go beyond the restriction of oxygenates compounds in the gasoline composition.


Claims

1. Gasoline composition comprising hydrocarbons mixture with from 6 to 100% by volume of isooctane and from 0 to 94% by volume of compound comprising oxygen.
 
2. Gasoline composition according to claim 1 comprising from 6 to 99.5 % by volume of isooctane.
 
3. Gasoline composition according to claim 1 comprising from 6 to 40% by volume of isooctane.
 
4. Gasoline composition according to claim 1 comprising from 6 to 30% by volume of isooctane.
 
5. Gasoline composition according to anyone of claims 1 to 4, wherein the compound comprising oxygen can be chosen among alcohol or ether.
 
6. Gasoline composition according to anyone of claims 1 to 5, wherein the oxygenate comes from renewable ressources.
 
7. Gasoline composition according to anyone of claims 1 to 6 wherein the compound comprising oxygen is chosen among ethanol, isopropanol, n-butanol, isobutanol, tert-butanol, isoamyl alcohol, isoprenol, prenol, ETBE, MTBE, TAME.
 
8. Gasoline composition according to anyone of claims 1 to 7, wherein the isooctane comes from renewable ressources, especially from isobutene produced by direct fermentation.
 
9. Use of isooctane as a gasoline composition or in a gasoline composition to reduce particulate emission.
 
10. Use according to claim 8 wherein the amount of isooctane is from of 6 to 100 vol%, preferably from 6 to 99.5 vol%, more preferably from 6 to 40 vol%, for example from 6 to 35 vol%.
 
11. Use of a combination of isooctane and oxygenates in a gasoline composition to reduce particulate emission.
 
12. Use according to claim 11, wherein the amount of isooctane is from 6 to 100%, preferably from 6 to 99.5%, more preferably from 6 to 40%, for example from 6 to 35%, by volume and the amount of oxygenates is from 0 to 94%, preferably from 0 to 30%, by volume based on the volume of the gasoline composition.
 
13. A method for reducing the particulate emissions of an engine car comprising the use of isooctanol as gasoline composition or in the gasoline composition used in the engine.
 
14. A method for reducing the particulate emissions of an engine car comprising the use of a gasoline composition according to anyone of claims 1 to 7.
 




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Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description




Non-patent literature cited in the description