Fuel composition with a low impact on co2 emissions, and use thereof in particular in new vehicles

Abstract

One object of the present invention is a fuel composition comprising:(i) from 85 to 98% by weight of a mixture of hydrocarbons comprising:a) from 8 to 40% by weight of aromatic compounds;b) from 50 to 90% by weight of non-cyclic paraffins containing at least 4 carbon atoms; andc) from 2 to 15% by weight of naphthenes; and(ii) from 2 to 15% by weight of ethanol,this composition having a density at 15° C., measured according to standard EN ISO 12185, in the range from 720 to 745 kg / m3.This composition is useful for powering a spark-ignition engine, and especially as a so-called “first fill fuel” for vehicles equipped with new engines.

Description

[0001] One object of the present invention is a fuel composition for vehicles including a spark-ignition engine (or gasoline engine), which has particular properties.

[0002] Another object of the invention is the use of such a composition for powering a spark-ignition engine, both in a conventional, especially automotive, vehicle and in a racing vehicle. The invention is more particularly directed to the use of this composition as a first fuel in a new engine.

[0003] Gasoline-type fuels marketed in Europe for use in spark-ignition engines, especially those used in automotive vehicles, have to meet the specifications of standard EN 228, which defines a number of criteria, such as a Motor Octane Number (MON) greater than 85 and a Research Octane Number (RON) of at least 95. In a manner well known per se, the octane number measures the resistance to auto-ignition of a fuel used in a spark-ignition engine.

[0004] These fuels are suitable for the majority of automotive engines.

[0005] However, special requirements apply when the gasoline fuel is a so-called “first fill fuel”, i.e. a fuel for powering a new engine, such as typically an engine equipping a new vehicle.

[0006] A new engine designates an engine that has not yet been used after manufacture.

[0007] In particular, at the end of automotive vehicle assembly lines, tanks in new vehicles are filled in whole or in part with a first fill fuel, which corresponds to the very first fuel which powers the engine at the time of the vehicle entry into service.

[0008] These first fill fuels have to meet very specific technical requirements.

[0009] A first set of requirements is imposed by the many starts and stops of vehicles without the vehicle rolling off the assembly line, and which should be carried out without generating any engine fouling. Under these conditions, first fill fuels have to protect new engines, guaranteeing their cleanliness and proper working until the vehicle is delivered to the first customer.

[0010] Furthermore, after they have been manufactured, automotive vehicles are often stored and shipped around the world before their first entry into service. The first fill fuel is thus stored for long periods, often several months, in the vehicle before being consumed by the end user of the vehicle. The first fill fuel should therefore have excellent long-term storage stability, especially oxidation stability.

[0011] Additionally, the vehicle is often put into service in a marketing location very far away from its place of manufacture: this may be on different continents, with fundamentally different weather conditions. However, starting the vehicle by the end user should pose no difficulty. For this, the first fill fuel should enable the vehicle to start immediately and run smoothly regardless of its marketing location, both in hot regions and in very cold countries.

[0012] Finally, as the engines are started and stopped several times on assembly lines right up to their final sale, operators working on assembly lines are particularly exposed to emissions generated by the combustion of fuel. For this reason, it is also important that the first fill fuel has a high level of safety. In particular, health, safety and environmental restrictions imposed by some auto manufacturers can be stringent in order to avoid any toxicity of the fuel for operators who have to handle it on a regular basis.

[0013] Thus, first fill fuels are subject to much higher technical, logistical and environmental requirements than conventional fuels sold at service stations.

[0014] Additionally, for all vehicles, especially those intended for consumer applications, there is a growing trend towards the use of fuels formulated from plant-based bases, and especially so-called “bio-sourced” bases, in order to meet environmental concerns and limit the use of fossil resources. Thus, current environmental concerns are driving consumers to search for more environmentally-friendly fuels.

[0015] However, the use of fuel compositions from biosourced bases must not be to the detriment of fuel performance.

[0016] There is therefore a need to develop new fuel compositions for powering spark-ignition engines that meet the requirements of modern vehicles, while being formulated from bases and / or compounds of renewable origin, also referred to as biosourced compounds.

[0017] There is also a need to formulate fuels that meet the specific requirements of first fill fuels, which can also be formulated from biosourced bases.

[0018] As is well known in prior art, octane improver additives (or octane boosters) are typically added to gasoline-type fuel compositions. Organometallic compounds in particular comprising iron, lead or manganese are well known octane improvers.

[0019] Thus, tetraethyl lead (TEL) has been widely used as a highly effective octane improver. However, in most parts of the world, TEL and other organometallic compounds can now only be used in fuel in very small quantities, if at all, because they can be toxic, damage the engine and are harmful to the environment.

[0020] Non-metal based octane improvers comprise oxygen compounds (e.g. ethers and alcohols) and aromatic amines. However, these additives also suffer from a number of drawbacks. For example, N-methylaniline (NMA), an aromatic amine, has to be used at a relatively high treatment rate (1.5 to 2% additive mass / fuel base mass) to have a significant effect on the octane number of the fuel. NMA can also be toxic.

[0021] By way of example, document U.S. Pat. No. 4,812,146 describes unleaded gasoline fuel compositions for racing engines which comprise at least four components selected from butane, isopentane, toluene, MTBE (methyl tert-butyl ether) and an alkylate.

[0022] Document WO2010 / 014501 describes unleaded gasoline fuel compositions comprising at least 45% by volume of branched paraffins, at most 34% by volume of one or more mono- and di-alkylated benzenes, from 5 to 6% by volume of at least one linear paraffin having from 3 to 5 carbon atoms (denoted C3-C5), one or more alkanols having from 2 to 4 carbon atoms (denoted C2-C4), in a sufficient amount to increase AKI (i.e. Anti Knock Index) i.e. (RON+MON) / 2 of at least 93. These compositions are claimed to have high torque and maximum power.

[0023] Thus, fuel compositions with good intrinsic properties, i.e. without the need necessarily to add octane improver additives such as those described hereinbefore, are sought.

[0024] Continuing its research into the development of fuel formulations for gasoline engines, the Applicant has now discovered a composition which makes it possible to meet the hereinbefore objectives.

[0025] One object of the present invention is therefore a fuel composition comprising:

[0026] (i) from 85 to 98% by weight of a mixture of hydrocarbons comprising:

[0027] a) from 8 to 40% by weight of aromatic compounds;

[0028] b) from 50 to 90% by weight of non-cyclic paraffins containing at least 4 carbon atoms; and

[0029] c) from 2 to 15% by weight of naphthenes; and

[0030] (ii) from 2 to 15% by weight of ethanol,

[0031] this composition having a density at 15° C., measured according to standard EN ISO 12185, in the range from 720 to 745 kg / m3.

[0032] These compositions are intended to be used for powering spark-ignition engines (or gasoline engines). These engines can be found in any vehicle equipped with an internal combustion engine, including conventional vehicles as well as rechargeable and non-rechargeable hybrid electric vehicles and dual fuel vehicles. The compositions according to the invention are also useful for powering a dual fuel compression ignition engine.

[0033] The fuel compositions according to the invention are in accordance with specification of standard EN 228. In particular, they have high RON and MON octane numbers.

[0034] The compositions according to the invention are particularly suitable for uses in which restrictions and requirements are extremely high, for example in vehicles equipped with new engines. Thus, the compositions according to the invention constitute particularly high-performance so-called first fill fuels.

[0035] They are extremely storage-stable and can withstand very wide temperature variations. They can be used in a wide range of weather conditions, from hot to very cold regions. They do not foul engines and have good safety properties.

[0036] The composition according to the invention also offers significant advantages for uses other than in vehicles equipped with new engines, such as, for example, so-called consumer uses, especially for light duty vehicles (or LDVs). If necessary, it should comply with the specifications of standard EN 228.

[0037] According to a particularly advantageous embodiment, the composition according to the invention can be prepared, in whole or in part, from biomass and especially from bases and / or compounds of plant origin(s). In particular, the composition according to the invention can contain at least 30% by weight of one or more biosourced bases, preferably at least 50% by weight, more preferably at least 80% by weight and still better at least 90% by weight of one or more biosourced bases. According to one particular embodiment, the composition according to the invention is entirely comprised of biosourced compounds (content greater than 99.9% by weight).

[0038] Thus, it offers a very substantial gain in carbon dioxide (CO2) equivalent compared with a fossil base, in the order of at least 20% compared with a conventional fuel that does not contain hydrocarbons derived from biomass, such as a hydrocarbon-based fuel of fossil (petroleum) origin.

[0039] This gain in CO2 equivalent is calculated over the entire life cycle of the fuel composition, from manufacture to use. It corresponds to a reduction in greenhouse gas emissions and can be determined by life cycle analysis, in accordance with standard ISO 14040-44.

[0040] Another object of the invention is the use of the fuel composition defined hereinbefore to power a spark-ignition engine.

[0041] According to one particularly advantageous embodiment, the composition according to the invention is used as a fuel for the first fill of a new engine, i.e. as a “first fill” fuel. In other words, the composition is used to power a new engine in an automotive vehicle.

[0042] Other objects, characteristics, aspects and advantages of the invention will appear more clearly upon reading the following description and examples.

[0043] In what follows, and unless otherwise indicated, the bounds of a range of values are included in this range, especially in the expressions: “between . . . and . . . , “in the range from . . . to . . . ”, and “ranging from . . . to . . . ”.

[0044] Moreover, the expressions “at least one” and “at least” used in the present description are respectively equivalent to the expressions “one or more” and “higher than or equal to”.

[0045] Finally, in a manner known per se, a CN compound designates a compound containing N carbon atoms in its chemical structure.The Fuel Composition

[0046] The composition according to the invention contains a mixture (i) of hydrocarbons containing:

[0047] a) from 8 to 40% by weight of aromatic compounds;

[0048] b) from 50 to 90% by weight of non-cyclic paraffins containing at least 4 carbon atoms; and

[0049] c) from 2 to 15% by weight of naphthenes.

[0050] These contents are expressed by weight, relative to the weight of the mixture (i) of hydrocarbons.

[0051] The mixture (i) of hydrocarbons represents from 85 to 98% by weight, relative to the total weight of the fuel composition, preferably from 88 to 95% by weight, relative to the total weight of the fuel composition.

[0052] The aromatic compound(s) (i)a) is (are) preferably chosen from alkyl benzenes comprising from 7 to 12 carbon atoms. Alkyl benzenes designate, in a manner known per se, benzene derivatives in which one or more hydrogen atoms are replaced with one or more alkyl groups.

[0053] The aromatic compound(s) may in particular be selected from toluene, ethylbenzene, xylenes (and especially 1,2-dimethylbenzene or ortho-xylene, 1,3-dimethylbenzene or meta-xylene and 1,4-dimethylbenzene or para-xylene), 1-ethyl-3-methylbenzene, mesitylene (1,3,5-trimethylbenzene), 1-ethyl-3,5-dimethylbenzene, and mixtures thereof.

[0054] Mixtures of aromatic compounds are particularly preferred, and more particularly mixtures of alkyl benzenes comprising from 8 to 10 carbon atoms, such as ethyl benzene, xylenes (and especially 1,2-dimethylbenzene or ortho-xylene, 1,3-dimethylbenzene or meta-xylene and 1,4-dimethylbenzene or para-xylene), 1-ethyl-3-methylbenzene, mesitylene (1,3,5-trimethylbenzene) and 1-ethyl-3,5-dimethylbenzene.

[0055] The content of aromatic compounds (i)a) represents from 8 to 40% by weight, preferably from 10 to 30% by weight, and better from 12 to 25% by weight, relative to the weight of the mixture of hydrocarbons (i).

[0056] The composition according to the invention further contains non cyclic paraffins (i)b) containing at least 4 carbon atoms.

[0057] “Paraffins” designate in a manner known per se branched alkanes (also called iso-paraffins or iso-alkanes) and unbranched alkanes (also called n-paraffins or n-alkanes).

[0058] Paraffins are preferably selected from those comprising from 5 to 12 carbon atoms, more preferably from 5 to 9 carbon atoms.

[0059] Paraffins can be selected from n-paraffins (or normal-paraffins, i.e. linear alkanes) and iso-paraffins (i.e. branched alkanes).

[0060] Mixtures of n-paraffins and iso-paraffins selected from those described hereinbefore are particularly preferred, preferably comprising a major proportion of iso-paraffins, with a ratio by weight of the amount of iso-paraffins to the amount of n-paraffins greater than or equal to 6, preferably greater than or equal to 8 and still better greater than or equal to 10. According to one preferred embodiment, this ratio is in the range from 8 to 20, preferably from 10 to 18, and still better from 12 to 15.

[0061] The mixture of hydrocarbons (i) advantageously contains from 3 to 10% by weight of n-paraffins and from 40 to 87% by weight of iso-paraffins.

[0062] Preferably, the content of paraffins (i)b) ranges from 60 to 90% by mass, more preferably from 70 to 85% by weight, relative to the weight of the mixture of hydrocarbons (i).

[0063] The composition according to the invention further contains naphthenes (i)c).

[0064] “Naphthenes” designate in a manner known per se cyclic alkanes (or cycloalkanes) containing from 5 to 12 carbon atoms. Preferably, naphthenes are selected from cyclic alkanes containing from 5 to 12 carbon atoms, and more preferably from 6 to 9 carbon atoms.

[0065] Preferably, the content of naphthenes (i)c) ranges from 2 to 10% by weight, more preferably from 3 to 6% by weight, relative to the weight of the mixture of hydrocarbons (i).

[0066] According to one preferred embodiment, the mixture (i) of hydrocarbons is at least 20% by weight derived from the processing of plant raw materials. Thus, the mixture (i) advantageously consists in whole or in part of biosourced hydrocarbons, and preferably entirely of biosourced hydrocarbons. Plant based raw materials can be for example selected from cereals (wheat, maize), rapeseed, sunflower, soya, palm oil, sugar cane, beet, plant waste such as for example wood waste, straw, bagasse, grape marc, used cooking vegetable oils, algae and lignocellulosic materials.

[0067] The composition according to the invention also contains ethanol.

[0068] According to one preferred embodiment, ethanol of plant origin, also called bioethanol, is used.

[0069] Bioethanol can be produced, for example, from the fermentation of sugars, mainly glucose, using conventional or genetically modified yeast strains. Different plant raw materials can be used to produce bioethanol, including sugar cane, maize, barley, potato waste, sugar beet and wine residues such as grape marc.

[0070] The composition has an ethanol content ranging from 2 to 15% by weight, preferably from 5 to 12% by weight, relative to the total weight of the fuel composition.

[0071] According to one advantageous embodiment, the composition according to the invention comprises at most 2% by weight of olefins, preferably at most 1.5% by weight of olefins, more preferably at most 1% by weight of olefins, even more preferably at most 0.5% by weight of olefins, relative to the total weight of the fuel composition.

[0072] According to one preferred embodiment, the composition according to the invention comprises at most 0.1% by weight of benzene. In other words, its benzene content is less than or equal to 0.1% by weight, relative to the total weight of the composition.

[0073] The composition according to the invention may further comprise one or more ethers. Ethers, also called ether oxides or alkoxy alkyls, are compounds of the formula R—O—R′, wherein R and R′, which may be identical or different, represent an alkyl radical, typically a C1 to C5 radical.

[0074] Mention will be made in particular of the following ethers, which are often incorporated into fuel compositions: methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), tert-amyl ethyl ether (TAEE), and mixtures thereof.

[0075] The composition has a density at 15° C., measured according to standard EN ISO 12185, in the range from 720 to 745 kg / m3. Preferably, the density is in the range from 720 to 730 kg / m3.

[0076] According to one preferred embodiment, the composition according to the invention has a final distillation point, measured according to the standard EN ISO 3405, of greater than 190° C., preferably greater than or equal to 195° C.

[0077] The composition as described hereinbefore generally has a research octane number (RON) greater than or equal to 95, preferably greater than or equal to 99, and more preferably greater than or equal to 100, the RON being measured according to standard EN ISO 5164.

[0078] It generally has a motor octane number (MON) greater than or equal to 85, preferably greater than or equal to 88, and more preferably greater than or equal to 90, the MON being measured according to standard EN ISO 5163.

[0079] The hereinbefore values concern the intrinsic octane number of the composition, i.e. without the addition of supplementary compounds such as especially octane boosting additives.

[0080] In addition to the base compounds described hereinbefore, the fuel composition according to the invention may also comprise one or more additives selected from those normally used in gasoline fuels.

[0081] In particular, the composition according to the invention can comprise at least one detergent additive ensuring cleanliness of the intake circuit. Such an additive may, for example, be selected from the group consisting of succinimides optionally substituted with a polyisobutylene group, polyetheramines, betaines, Mannich bases and quaternary ammonium salts, for example those described in documents U.S. Pat. No. 4,171,959 and WO2006135881.

[0082] The composition may also comprise at least one lubricity additive or anti-wear agent, especially (but not limited to) selected from the group consisting of fatty acids and their ester or amide derivatives, especially glycerol monooleate, and mono- and polycyclic carboxylic acid derivatives. Examples of such additives are given in the following documents: EP680506, EP860494, WO98 / 04656, EP915944, FR2772783, FR2772784.

[0083] Other additives may also be incorporated into the fuel composition according to the invention, such as anti-valve recession additives and antioxidant additives, octane number-improving additives if necessary.

[0084] The additives described hereinbefore can be added in amounts ranging, for each of them, from 10 to 5000 ppm by weight, preferably from 50 to 1000 ppm by weight in the fuel composition.

[0085] According to a preferred embodiment, the composition comprises an additive package, i.e. a combination of at least two different additives, advantageously selected from detergent additives, lubricity additives, valve anti-recession additives and antioxidant additives. These additives are advantageously selected from those listed hereinbefore.

[0086] The fuel compositions according to the invention have a lead content generally less than or equal to 5 mg / L (present, for example, in the form of tetraethyl lead) and, preferably, are unleaded, i.e. they do not contain lead or lead-containing compounds.Preparation of the Fuel Composition

[0087] The composition according to the invention can be prepared by simply mixing its constituents.

[0088] A non-limiting embodiment comprises the following steps:

[0089] 1) preparing a mixture of hydrocarbons (i) comprising from 8 to 40% by weight of aromatic compounds, from 50 to 90% by weight of non-cyclic paraffins containing at least 4 carbon atoms and from 2 to 15% by weight of naphthenes; and then

[0090] 2) mixing from 85 to 98% by weight of said mixture (i) with from 2 to 15% by weight of ethanol.

[0091] The mixture of hydrocarbons (i) preferably comprises one or more biosourced bases by at least 20% by weight, i.e. at least 20% by weight of the hydrocarbons have been obtained from plant raw materials. More preferably, the mixture of hydrocarbons (i) comprises one or more biosourced bases by at least 30% by weight, more preferably at least 50% by weight and still better at least 70% by weight. These amounts are expressed relative to the total weight of the mixture of hydrocarbons (i).

[0092] The mixture of hydrocarbons (i) may further comprise non-biosourced hydrocarbons, such as hydrocarbons of fossil (petroleum) origin, preferably in a minor amount, typically less than 80% by weight, preferably less than 70% by weight, more preferably less than 50% by weight, better less than 30% by weight. These amounts are expressed relative to the total weight of the mixture of hydrocarbons (i).

[0093] According to one particularly preferred embodiment, the mixture of hydrocarbons (i) entirely consists of one or more biosourced bases.

[0094] As preferred biosourced bases, those produced from biomass, converted into bio-hydrocarbons by known catalytic conversion processes, can especially be used.

[0095] Likewise, ethanol is preferably bioethanol.

[0096] Thus, the composition according to the invention can be entirely prepared from plant raw materials.The Uses

[0097] Another object of the invention is the use of the composition as described hereinbefore to power a spark-ignition engine. The engine may be of the direct injection or indirect injection type.

[0098] The fuel composition can advantageously be used both to power a conventional automotive vehicle engine (so-called “consumer”) and a high-power spark-ignition engine, such as an automotive racing vehicle engine. This could especially be a naturally-aspirated or turbocharged engine used in a racing vehicle (circuits or rallies), or a hybrid engine, i.e. an internal combustion engine coupled to an electric motor, either rechargeable (or PHEV for “Plug-in Hybrid Electric Vehicle”) or non-rechargeable (or HEV for “Hybrid Electric Vehicle”).

[0099] According to one preferred embodiment, the composition according to the invention is used as a “first fill” fuel, i.e. as a fuel for the first fill in a vehicle comprising a new engine. In other words, the composition is used to power a new engine of a vehicle, especially an automotive or other vehicle (heavy goods vehicle, public transport vehicle or other), preferably an automotive vehicle.

[0100] Another object of the invention is the use of the composition as described hereinbefore to reduce equivalent carbon dioxide emissions, measured by life cycle analysis in accordance with standard ISO 14040-44. This reduction is typically determined relative to a fossil reference, especially an equivalent petroleum-based fuel composition.

[0101] The examples hereinafter are intended solely to illustrate the invention and should not be construed as limiting the scope thereof.EXAMPLE

[0102] The example hereinafter has been carried out using a base B comprising 22% by weight of biosourced hydrocarbons derived from the processing of bio-alcohol which is derived from the processing of biomass.

[0103] Base B has the following composition:TABLE 1CompoundsContent (% by weight)Olefins0.40C6-C11 aromatic compounds15.2C5-C9 N-paraffins5.2C5-C11 Isoparaffins75.5Naphthenes3.7

[0104] A fuel composition C has been prepared by mixing:

[0105] 89.58% by weight of base B, and

[0106] 10.42% by weight of bioethanol.

[0107] This composition has a density at 15° C., measured according to standard EN ISO 12185, of 722 kg / m3.

[0108] Its final distillation point, measured according to standard EN ISO 3405, is 195° C.

[0109] It has a Research Octane Number (RON, measured according to standard EN ISO 5164) of 100.4 and a Motor Octane Number (MON, measured according to standard EN ISO 5163) of 91.5.

[0110] Compared to an equivalent fuel composition of petroleum origin (i.e. comprising 89.58% by weight of fossil hydrocarbons and 10.42% by weight of bioethanol), the composition C described above resulted in a gain of 21% in CO2 equivalents. This gain has been calculated by life cycle analysis, in accordance with standard ISO 14040-44.

Claims

1. A fuel composition comprising:(i) from 85 to 98% by weight of a mixture of hydrocarbons comprising:a) from 8 to 40% by weight of aromatic compounds;b) from 50 to 90% by weight of non-cyclic paraffins containing at least 4 carbon atoms; andc) from 2 to 15% by weight of naphthenes; and(ii) from 2 to 15% by weight of ethanol,this composition having a density at 15° C., measured according to standard EN ISO 12185, in the range from 720 to 745 kg / m3.

2. The composition according to claim 1 wherein the mixture of hydrocarbons (i) represents from 88 to 95% by weight, relative to the total mass of the fuel composition.

3. The composition according to claim 1 wherein the aromatic compounds (i)a) are selected from alkyl benzenes comprising from 7 to 12 carbon atoms.

4. The composition according to claim 1 wherein the content of aromatic compounds (i)a) is from 10 to 30% by weight, relative to the mass of the mixture of hydrocarbons (i).

5. The composition according to claim 1 wherein the non-cyclic paraffins (i)b) consist of a mixture of n-paraffins and iso-paraffins with a mass ratio of the amount of iso-paraffins to the amount of n-paraffins greater than or equal to 6.

6. The composition according to claim 1 wherein the mass ratio of the amount of isoparaffins to the amount of n-paraffins is from 8 to 20.

7. The composition according to claim 1 wherein the content of paraffins (i)b) is from 60 to 90% by weight, relative to the mass of the mixture of hydrocarbons (i).

8. The composition according to claim 1 wherein the naphthenes (i)c) are selected from cyclic alkanes containing from 5 to 12 carbon atoms.

9. The composition according to claim 1 wherein the content of naphthenes (i)c) is from 2 to 10% by weight, relative to the mass of the mixture of hydrocarbons (i).

10. The composition according to claim 1 wherein the composition ethanol content is from 5 to 12% by weight, relative to the total mass of the fuel composition.

11. The composition according to claim 1 wherein the composition comprises at most 2% by weight of olefins, relative to the total mass of the fuel composition.

12. The composition according to claim 1 wherein the composition benzene content is less than or equal to 0.1% by weight, relative to the total mass of the fuel composition.

13. The composition according to claim 1 wherein the mixture of hydrocarbons (i) is derived from at least 20% by weight from the processing of plant raw materials.

14. The composition according to claim 1 wherein the composition is in contact with a spark ignition engine.

15. The composition according to claim 1 wherein the composition is a first fill fuel in a vehicle comprising a new engine.

16. The composition according to claim 1 wherein the composition has a decrease in equivalent carbon dioxide emissions compared to an equivalent fuel composition of petroleum origin comprising 89.58% by weight of fossil hydrocarbons and 10.42% by weight of bioethanol, measured by life cycle analysis in accordance with standard ISO 14040-44.