JPH07179868A - Fuel oil composition for internal combustion engine - Google Patents

Abstract

PURPOSE:To obtain a fuel oil composition excellent in the prevention of smoldering and also in the capability of accelerating, starting and running an internal combustion engine. CONSTITUTION:This composition comprises a hydrocarbon oil having an aromatic content of 20-50vol.% based on the whole hydrocarbon, a content of 8 C and 9 C aromatic of 40-100vol.% based on the whole aromatics, a research octane number of 96 or above, a boiling point in the range of the boiling point of gasoline and a distillation behavior in which a 50% evaporation temperature is 105 deg.C or below.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel oil composition for an internal combustion engine, and more specifically, in a spark ignition engine, it is possible to suppress the contamination of a spark plug with carbon, which is excellent in acceleration, startability and drivability. And a fuel oil composition for an internal combustion engine.

[0002]

2. Description of the Related Art In an internal combustion engine such as a gasoline engine,
Smoldering of the spark plug may occur. This phenomenon is caused by the glass insulation of the spark plug due to the carbon-like substance generated by the incomplete combustion of the fuel especially during short-distance driving in cold weather (for example, during delivery from factory shipment to dealer delivery) or during traffic congestion in the city. It is a phenomenon that causes a so-called misfire, in which the leakage current increases and the spark does not fly due to the accumulation on the body. As a result, the internal combustion engine becomes unstartable or causes problems such as an increase in unburned hydrocarbons in exhaust gas and deterioration of drivability even if the phenomenon is slight. As a method for suppressing this smoldering property, a phthalic acid diester as a smoldering property suppressing additive is currently used (Japanese Patent Laid-Open No. 61-1766).
94), alkaline earth metal phenates (JP-A-6-6
No. 1-174298), barium compounds (Japanese Patent Application Laid-Open No. Sho 6-62)
1-111396 gazette) and methyl tertiary butyl ether (MTBE), and a method of reducing the aromatic content in gasoline.

However, as a method of preventing smoldering of the spark plug, the conventional method of adding a smoldering suppressing additive or the like has a problem of increasing gasoline production cost. On the other hand, the smoldering property is more likely to occur as the aromatic content in the fuel is higher, so a method of reducing the aromatic content can be considered. However, with this method, the octane number of the gasoline itself is lowered, and the quality of the gasoline is degraded, and if the octane number is increased by newly adding an octane booster base material, there is a problem that the gasoline production cost is increased.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the situation of the above-mentioned prior art, and can suppress the smolder property without using a special anti-smolder property additive. It is an object of the present invention to provide a high octane fuel oil composition for internal combustion engines, which is excellent in acceleration, startability and drivability.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have set the composition and content of aromatic components in fuel oil within a specific range, and have a distillation property. By making it a specific one and setting the research method octane number to 96 or more, the smoldering property can be suppressed without the administration of the conventional smoldering property suppressing additive for spark plugs and without reducing the aromatic content. They have found that they exhibit acceleration, startability, and drivability, and have completed the present invention based on this finding.

That is, according to the present invention, the total aromatic content is 2%.
0 to 50% by volume, the content of aromatics having 8 and 9 carbon atoms with respect to the total aromatics is 40 to 100% by volume, the research octane number is 96 or more, and the boiling point is the gasoline boiling temperature range. The present invention provides a fuel oil composition for an internal combustion engine, which comprises a hydrocarbon oil having a distillation property at a distillation temperature of 105 ° C. or less at a 50% distillation amount. Hereinafter, the present invention will be described in detail.

The fuel oil composition for an internal combustion engine of the present invention comprises a hydrocarbon oil having a specific distillation property. The boiling point of this hydrocarbon oil may be in the boiling point temperature range of gasoline, specifically in the temperature range of 20 to 210 ° C, and preferably in the temperature range of 30 to 190 ° C. Further, this hydrocarbon oil needs to have a distillation temperature of 105 ° C or lower at a 50% distillation amount, preferably 85 to 105 ° C. If the distillation temperature at a 50% distillation amount exceeds 105 ° C, the acceleration, startability, and drivability will be poor. Further, since the fuel oil composition becomes heavy and the startability is poor at low temperatures, smoldering of the spark plug is likely to occur.

In the fuel oil composition for an internal combustion engine of the present invention, the hydrocarbon oil must have an aromatic content of 20 to 50% by volume, preferably 30 to 50% by volume, and particularly preferably. Is 30 to 45% by volume. When the content of the aromatic component exceeds 50% by volume, the smoldering property is deteriorated, the effect of suppressing the smoldering property is deteriorated, the fuel oil composition becomes heavy, and the evaporation property of the fuel is inferior. Problems such as deterioration of used rubber and increase of harmful substances in exhaust gas occur. When the content of the aromatic component is less than 20% by volume, the octane number is lowered, and a fuel oil composition having a research octane number of 96 or more cannot be obtained.

In the fuel oil composition for an internal combustion engine of the present invention, the content ratio of the aromatic components having 8 and 9 carbon atoms to the total aromatic components is required to be 40 to 100% by volume, preferably. 50 to 100% by volume, more preferably 65 to 100% by volume, and particularly preferably 80 to
It is 100% by volume. If the content of the aromatic component having 8 or 9 carbon atoms is less than 40% by volume, the smoldering property is poor.

The aromatic component having 8 and 9 carbon atoms has 8 carbon atoms.
The aromatic hydrocarbons having 8 and 9 carbon atoms represented by the following general formula (1) are not particularly limited as long as they are various aromatic hydrocarbons having 9 and 9; Can be mentioned.

[0011]

[Chemical 1]

(In the formula, R represents an alkyl group having 1 to 3 carbon atoms, and n represents an integer of 1 to 3) In the general formula (1), R is an alkyl group having 4 or more carbon atoms, and When n is an integer of 4 or more, the boiling point becomes high, which is not preferable as a fuel oil base material for an internal combustion engine. Examples of the aromatic hydrocarbon having 8 and 9 carbon atoms represented by the general formula (1) include aromatic hydrocarbons having a boiling point of about 130 to 180 ° C., and specific examples thereof include o-xylene and m.
-Each of xylene such as xylene and p-xylene, each of ethylbenzene, isopropylbenzene, n-propylbenzene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, etc. Examples include trimethylbenzene and methylethylbenzene. Among these aromatic hydrocarbons, those in which a large amount of alkyl groups are substituted and those in which the alkyl group has a long carbon chain and whose boiling point is in the range of about 130 to 160 ° C. are particularly preferable. Specifically, xylene, ethylbenzene, isopropylbenzene, and n-propylbenzene are preferable.

In the fuel oil composition for an internal combustion engine of the present invention, the hydrocarbon has a research octane number of 96 or more, preferably 98 or more.

Examples of the base material that can be used in the fuel oil composition for an internal combustion engine of the present invention include catalytic reforming gasoline, catalytic cracking gasoline, alkylate, and the like. If necessary, naphtha or light naphtha, isopentane, Isooctane, xylene, ethylbenzene, aromatic compounds having 9 carbon atoms,
Other substrates such as oxygenates can be used.
Contact reformed gasoline (hereinafter simply referred to as reformed gasoline)
In general, heavy straight run naphtha and the like are widely known by catalytic reforming methods (plating method, magnaforming method, aromatizing method, reniforming method, hood reforming method, ultraforming method, power And a catalyst (for example, an alumina carrier on which platinum or rhodium and chlorine are supported) under a high temperature and high pressure in a hydrogen stream by a forming process). Octane number of about 95 or more, preferably 98 or more, and boiling range of about 28.
~ 200 ° C, or benzene, which is an aromatic distillate,
Reformed gasoline obtained by removing at least a part of toluene or the like by extraction or distillation, or those obtained by various catalytic reforming methods to which xylene, ethylbenzene, and aromatic compounds having 9 carbon atoms are added can be preferably used. .

Catalytic cracking gasoline is a wide range of petroleum fractions ranging from kerosene and light oil to atmospheric residual oil, preferably heavy gas oil and vacuum gas oil, which have been widely known in the past, and particularly fluid catalytic cracking method. (UOP method, shell two-stage method, flexi cracking method, ultra orthoflow method, Texaco method,
Gulf method, Ultracat cracking method, RCC
Method, HOC method, etc.) is a catalytically cracked gasoline obtained by cracking with a solid acid catalyst (for example, silica, alumina, or silica-alumina mixed with zeolite). In the present invention, the research octane number is about 90.
The above, for example, about 90 to 96.5, preferably about 93 or more, for example, about 93 to 96.5 can be suitably used,
Further, a light component having a boiling point range of 20 to 150 ° C. is also used. Of course, a combination of a fraction having a distillation property in a full range of about 20 to 200 ° C. and a light fraction is also possible.

The alkylate is obtained by reacting isobutane with a lower olefin (butene, propylene, etc.) as a raw material in the presence of an acid catalyst (sulfuric acid, hydrogen fluoride, aluminum chloride, etc.). In the present invention, various alkylates can be used as components,
Isooctane fraction such as 4-trimethylpentane is 40
Those having a volume% or more and a research octane number of about 93 or more are preferably used. Light naphtha is a fraction having a boiling point range of about 30 to 80 ° C. obtained from an atmospheric distillation device.

The fuel oil composition for an internal combustion engine of the present invention can be produced by appropriately selecting the base material. Suitable examples of the fuel oil composition for an internal combustion engine of the present invention include reformed gasoline, alkylate, catalytically cracked gasoline, and light naphtha, if necessary, and other base materials such as xylene, ethylbenzene, and carbon. What is produced by blending the aromatic component of number 9, butane, butenes, isooctane, isopentane, etc., particularly preferably reformed gasoline, alkylate, catalytic cracking gasoline, light naphtha, xylene, ethylbenzene, carbon The thing manufactured by mix | blending the aromatic etc. of several 9 is mentioned. For example, reformed gasoline,
When the fuel oil composition for an internal combustion engine according to the present invention is produced using alkylate and catalytically cracked gasoline, the reformed gasoline is approximately 40 to 65% by volume, the alkylate is 5 to 35% by volume, and the catalytically cracked gasoline. Alternatively, light catalytic cracking gasoline may be appropriately blended in the range of about 5 to 30% by volume.

For the purpose of improving the octane number of the fuel oil composition for internal combustion engine of the present invention, methyl-t-butyl ether (MTBE), t-aminomethyl ether (TA
ME), ethers such as ethyl-t-butyl ether (ETBE) and alcohols such as methanol, ethanol, isopropanol and t-butanol may be added. Furthermore, an antioxidant and a detergent-dispersant can be added to the fuel oil composition for an internal combustion engine of the present invention, if necessary. Examples of the antioxidant include 2,6-di-ter
t-butyl-4-methylphenol, 2,4-dimethyl-6-tert-butylphenol, 2,6-di-te
rt-butylphenol, 75% or more of 2,6-di-t
A mixture of ert-butylphenol and 25% or less of tert-butylphenol, 72% or more of 2,4-dimethyl-1,6-tert-butylphenol and 28% or more of phenolic antioxidants such as monomethyl and dimethyl-tert-butylphenol. , N, N'-diisopropyl-p-phenylenediamine, N, N'-di-se
Examples thereof include amine-based antioxidants such as c-butyl-p-phenylenediamine, and preferred examples include N,
N'-diisopropyl-p-phenylenediamine, N,
Amine antioxidants such as N'-di-sec-butyl-p-phenylenediamine may be mentioned. Examples of the detergent dispersant include succinimide, polyalkylamine,
Examples include polyether amines. Furthermore, the fuel oil composition for an internal combustion engine of the present invention includes an antifreezing agent such as a polyhydric alcohol or an ether of a polyhydric alcohol such as ethylene glycol monomethyl ether, an alkali metal or an alkaline earth metal of an organic acid, if necessary. Salts, combustion improvers such as sulfates of higher alcohols, anionic surfactants, cationic surfactants, nonionic surfactants, antistatic agents such as amphoteric surfactants, and colorants such as azo dyes, etc.
Various fuel oil additives may be added alone or in combination of two or more. The amount of these fuel oil additives added is arbitrary, but it is generally preferable to add them so that the total amount added is 0.1% by weight or less.

[0019]

EXAMPLES Next, the present invention will be described more specifically by way of examples. The present invention is not limited to these examples. The properties of the reformed gasoline, light catalytic cracking gasoline, alkylate, and light naphtha used in the examples are shown in Table 1. The distillation property is JIS22.
54. The composition analysis is based on JIS253.
6 was measured.

[0020]

[Table 1]

Example 1 A mixture of butane-butenes produced from a catalytic cracking unit, a catalytic reforming unit and an atmospheric distillation unit with xylene, ethylbenzene, reformed gasoline, light catalytic cracking gasoline and alkylate as a base material is shown in Table 2. A gasoline of the stated composition was obtained.

Example 2 Gasoline shown in Table 2 was obtained by blending the butane-butenes described in Example 1 with xylene, light naphtha, isopentane and alkylate.

Example 3 Butane-butenes described in Example 1 and ethylbenzene,
Gasoline shown in Table 2 was obtained by blending light naphtha and alkylate.

Example 4 By blending the butane-butenes described in Example 1, 1,2,4-trimethylbenzene, light naphtha and alkylate, gasoline shown in Table 2 was obtained.

Example 5 The gasoline shown in Table 2 was obtained by blending the butane-butenes described in Example 1 with reformed gasoline, light cracked gasoline and alkylate.

Comparative Example 1 Gasoline shown in Table 3 was obtained by blending the butane-butenes described in Example 1 with toluene, isopentane and alkylate.

Comparative Example 2 By blending the butane-butenes described in Example 1 with toluene, light naphtha and alkylate, gasoline shown in Table 3 was obtained.

Comparative Example 3 By blending the butane-butenes described in Example 1 with reformed gasoline, toluene, benzene, light cracked gasoline, and alkylate, gasoline shown in Table 3 was obtained. Using the gasolines of these Examples and Comparative Examples, the following smoldering performance evaluation test was conducted. The method is shown below, and the results are shown in Tables 2 and 3.

Smoldering performance evaluation test The following smoldering performance evaluation test was conducted using the above gasoline composition as a fuel using an engine equipped with an engine displacement of 2000 cc, an electronically controlled fuel injection system, and an automatic transmission. A new spark plug was attached to the test at the beginning of the test. The engine cooling temperature was adjusted to 0 to 2 ° C. using a constant temperature bath, and the test was conducted on a bench stand. The acceleration / deceleration mode for one pattern of about 2 minutes is repeated 10 times, and then stopped for 28 minutes. The test is repeated by setting this as one cycle.
To determine the smoldering stain of the spark plug, at the end of each cycle, measure the insulation resistance value between the electrodes of the plug, and the resistance value is 1
The test was terminated when it became 0 M ohms or less, and the number of test cycles required so far was taken as the number of cycles for evaluating the smoldering property. The larger the number of cycles showing smolderability, the greater the effect of suppressing smolderability.

[0030]

[Table 2]

[0031]

[Table 3]

In Tables 2 and 3, the unit of composition and composition of aromatics is% by volume. As is clear from the results of Tables 2 and 3, the fuel compositions in which xylene, ethylbenzene, trimethylbenzene and the like account for 40 to 100% by volume of the aromatic content in gasoline have excellent results in suppressing smoldering. showed that.

[0033]

INDUSTRIAL APPLICABILITY The fuel oil composition for an internal combustion engine of the present invention can be easily prepared, is excellent in the effect of suppressing smoldering, and is also excellent in acceleration, startability and drivability. Therefore, the fuel oil composition for an internal combustion engine of the present invention is extremely useful in practice.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Akira Hoizumi 1134-2 Gongendo, Satte City, Saitama Cosmo Research Institute Co., Ltd.

Claims (1)

[Claims] 1. The aromatic content is 20 to 50% by volume of the whole, the content ratio of the aromatic content having 8 and 9 carbon atoms is 40 to 100% by volume, and the research octane number is 96. Above, the boiling point is in the gasoline boiling temperature range, and the distillation temperature at a 50% distillation amount is 105 ° C.
A fuel oil composition for an internal combustion engine, comprising a hydrocarbon oil having the following distillation properties.