JP2007191580A - Internal combustion engine fuel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an internal combustion engine fuel that has no inferiority in engine low temperature startability, is grasped as circulation resources from a macroscopic viewpoint and can contribute to reduction of carbon dioxide in the atmosphere. <P>SOLUTION: This internal combustion engine fuel comprises 1-4C alcohol and a volatile organic material. The volatile organic material of the fuel has vapor pressure of 70-140 kPa at 37.8°C, a boiling point of ≥25°C and a flash point of ≤-30°C. The fuel has the vapor pressure of 30-70 kPa at 37.8°C and a research octane number of ≥90. All components contained in the fuel are derived from a living organism. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel for an internal combustion engine, and more particularly to a fuel for an internal combustion engine that can be generated from biological resources and can be recirculated from a macro viewpoint.

In recent years, alternative fuels have been actively researched as countermeasures against the depletion of petroleum resources. Examples of such alternative fuels include alcohols containing methanol and ethanol mixed with gasoline in addition to alcohols such as methanol and ethanol (alcohol fuels). Is known (see, for example, Patent Document 1).
JP 05-209579 A

However, since the conventional alcohol fuel is inferior in engine startability at a low temperature, in actuality, it is necessary to start the engine by supplying gasoline from a separate tank at a low temperature. In addition to an increase in the number of vehicles, there is a major problem in vehicle design, such as securing installation space.
In addition, when gasoline is not used in this way, the injector, fuel tank, and gallery must be heated before starting a low-temperature start. These heating energy is lost, and the installation cost and installation of the heating device are lost. Ensuring space was also a problem.

On the other hand, even in the case of alcohol-containing gasoline, it cannot be said that the above-mentioned problems at the time of low-temperature start have been sufficiently overcome, and a fuel heating device has to be installed separately, and there is a problem similar to the above.
In addition, since such alcohol-containing gasoline eventually uses gasoline, it cannot be said to be perfect as a countermeasure for depletion of petroleum resources, and the contribution to the reduction of carbon dioxide in the atmosphere is still insufficient.

  The present invention has been made in view of such problems of the prior art, and the object of the present invention is that the low temperature startability of the engine is inferior and is recognized as a circulating resource from a macro perspective, An object of the present invention is to provide a fuel for an internal combustion engine that can contribute to the reduction of carbon dioxide.

  As a result of intensive studies to achieve the above object, the present inventors have found that the above object can be achieved by using a predetermined alcohol and a volatile organic substance in combination, and have completed the present invention.

That is, the fuel for an internal combustion engine of the present invention is characterized by containing an alcohol having 1 to 4 carbon atoms and a volatile organic substance.
In a preferred embodiment of the fuel for an internal combustion engine of the present invention, the volatile organic substance has a vapor pressure of 70 to 140 kPa at 37.8 ° C.

  According to the present invention, since the predetermined alcohols and volatile organic substances are used in combination, the low temperature startability of the engine is not inferior, it is grasped as a circulation resource from a macro viewpoint, and it is also possible to reduce carbon dioxide in the atmosphere. A fuel for an internal combustion engine that can contribute can be provided.

Hereinafter, the fuel for an internal combustion engine of the present invention will be described in detail. In the present specification, “%” represents mass percentage unless otherwise specified.
As described above, the fuel for an internal combustion engine of the present invention contains an alcohol having 1 to 4 carbon atoms (C1 to C4) and a volatile organic substance.

Here, as C1-C4 alcohol, methanol, ethanol, propanol (propyl alcohol), and butanol (butyl alcohol) can be mentioned, These may have a branched chain.
In the present invention, ethanol can be preferably used from the viewpoint of a bioresource that is easily synthesized from alcohol fermentation of plants and can be easily circulated.

  Next, the volatile organic substance is not particularly limited as long as it satisfies the ignitability as a fuel for an internal combustion engine when used in combination with the above alcohol, particularly the ignitability at a low temperature of about -20 to 0 ° C. Examples thereof include alkanes having 3 or more carbon atoms (paraffinic hydrocarbons), alkenes (olefinic hydrocarbons), alkynes and structural isomers thereof, aromatic hydrocarbons, and oxygen-containing compounds of these hydrocarbons.

Examples of C3 or higher alkanes, alkenes or alkynes or structural isomers thereof include butane, isobutane, butene, isobutene, pentane, pentene, isopentene, hexane, isohexane, hexene, isohexene and cyclohexene.
Moreover, as an aromatic hydrocarbon, benzene, toluene, ethylbenzene, and xylene can be illustrated.

  Examples of the oxygen-containing compound of the hydrocarbon include alkyl ethers such as dimethyl ether (DME) and diethyl ether (DEE), tertiary butyl ethers such as methyl tertiary butyl ether (MTBE) and ethyl tertiary butyl ether (ETBE), methyl ethyl ketone ( Examples thereof include ketones such as MEK), dimethyl ketone (DMK) and diethyl ketone (DEK), and aldehydes such as propyl aldehyde and butyraldehyde.

In the present invention, an organic substance having a vapor pressure of 70 to 140 kPa at 37.8 ° C. can be preferably used as the volatile organic substance as described above.
If the vapor pressure at 37.8 ° C. is less than 70, the engine startability at low temperatures, particularly at −20 ° C., may be deteriorated. If it exceeds 140 kPa, the vapor pressure is too high, and the evaporation from the fuel storage device Gas (evaporation) may be generated.

In the present invention, n-pentane, trans-2-pentene, or diethyl ether and a mixture thereof can be given as typical examples of the above volatile organic substances, and these satisfy the above-mentioned physical properties and are particularly favorable. Can be used.
In the fuel for an internal combustion engine of the present invention, it is preferable to use a liquid at room temperature as the alcohol and the volatile organic substance in consideration of the ease of mixing operation at the time of production.

As described above, the fuel for an internal combustion engine of the present invention contains the above-mentioned alcohol and volatile organic substance, but preferably has a vapor pressure at −20 ° C. of 30 kPa or more and a vapor pressure at 40 ° C. of 70 kPa or less.
When the vapor pressure at −20 ° C. is less than 30 kPa, it is difficult to start an internal combustion engine such as an automobile engine in an environment at −20 ° C. or less. When the vapor pressure at 40 ° C. exceeds 70 kPa, fuel storage such as a fuel tank is stored. The amount of evaporation from the container increases.

The fuel for internal combustion engines of the present invention preferably has a research octane number of 90 or more.
If the octane number is less than 90, the engine may knock.

In the fuel for an internal combustion engine of the present invention, the selection of the above-mentioned alcohol and volatile organic substance and the blending ratio thereof can be appropriately changed according to the intended performance, particularly the above-described vapor pressure and octane number.
Typically, 70-85 vol% ethanol and 15-30 vol% volatile organics can be used.
If ethanol is less than 70 vol%, the ratio of ethanol used is low and tends not to contribute significantly to CO ₂ recirculation. If it exceeds 80 vol%, the vapor pressure may be less than 30 kPa, which may be undesirable.
On the other hand, if the volatile organic substance is less than 15 vol%, the vapor pressure may be less than 30 kPa, and if it exceeds 30 vol%, the use ratio of ethanol may be low and may not contribute significantly to CO ₂ recycling. .

Moreover, in the fuel for internal combustion engines of the present invention, it is desirable that all of the components contained therein are of biological origin.
In this way, if all of the contained components are bioresources that can be recycled (reused), carbon dioxide (CO ₂ ) emitted into the atmosphere by the operation of the internal combustion engine may be recycled and increase. Therefore, global warming can be extremely effectively suppressed.

Among the contained components, alcohol, particularly ethanol, can be obtained from plants as described above, but volatile organic substances such as n-pentane and n-hexane can also be produced by Fischer-Trops synthesis from plants. None are possible and do not increase CO ₂ in the atmosphere.

Since the internal combustion engine fuel of the present invention described above can achieve a higher octane number than gasoline, the compression ratio can be improved by about 2 to 3 in an automobile engine or the like, which can contribute to improvement in engine output and fuel consumption. .
Moreover, since it does not contain sulfur (S), SOx does not exist in the exhaust gas, and sulfur deactivation of the exhaust gas purification catalyst can be prevented.

Further, when an aromatic compound is not used as the volatile organic substance, the fuel is friendly to the human body. Furthermore, since alcohol is contained, HC (hydrocarbons) in the exhaust gas can be reduced, and an environmentally friendly fuel can be realized.
In addition, when ethanol or the like is used, the combustion speed becomes faster than that of gasoline, which can contribute to the improvement of the compression ratio.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to these Examples.

(Examples 1-3)
Ethanol, n-pentane, and other substances were mixed in the proportions shown in Table 1 to obtain fuels for internal combustion engines of the respective examples. The properties are also shown in Table 1.

(Performance evaluation)
[Octane number]
The measurement was performed according to JIS K2280. The obtained results are shown in Table 1.

[Vapor pressure]
The measurement was performed according to JIS K2258. The obtained results are shown in Table 1.

Claims (10)

  A fuel for an internal combustion engine comprising an alcohol having 1 to 4 carbon atoms and a volatile organic substance.   The fuel for an internal combustion engine according to claim 1 or 2, wherein the volatile organic substance has a vapor pressure of 70 to 140 kPa at 37.8 ° C.   The internal combustion engine fuel according to claim 1 or 2, wherein the volatile organic substance has a boiling point of 25 ° C or higher.   The internal combustion engine fuel according to any one of claims 1 to 3, wherein a flash point of the volatile organic substance is -30 ° C or lower.   2. The fuel for an internal combustion engine according to claim 1, wherein the volatile organic substance is at least one selected from the group consisting of n-pentane, trans-2-pentene and diethyl ether.   The fuel for an internal combustion engine according to any one of claims 1 to 5, wherein the alcohol is ethanol.   The fuel for an internal combustion engine according to any one of claims 1 to 6, wherein a vapor pressure at 37.8 ° C is 30 to 70 kPa.   The fuel for an internal combustion engine according to any one of claims 1 to 7, wherein a research octane number is 90 or more.   The fuel for an internal combustion engine according to any one of claims 6 to 8, comprising 70 to 85 vol% of ethanol and 15 to 30 vol% of the volatile organic substance.   The fuel for an internal combustion engine according to any one of claims 1 to 9, wherein all of the components are of biological origin.