JP4658990B2 - Method for producing fuel oil for gasoline engine - Google Patents

Description

  The present invention relates to a novel method for producing fuel oil for gasoline engines. More specifically, the present invention relates to a method for producing a fuel oil for a lead-free high-octane gasoline engine that has excellent driving performance and low pollution.

Since the addition of lead compounds such as tetraethyl lead as an octane improver has been regulated, unleaded high octane gasoline has been actively developed, and various unleaded high octane gasolines have been proposed and marketed. Furthermore, recently, unleaded high-octane gasoline to which oxygen-containing compounds such as alcohols and ethers are added has been proposed as a high-octane base.
As such a high octane gasoline, for example, gasoline obtained by adding methyl tertiary butyl ether (MTBE) to catalytically reformed gasoline and catalytically cracked gasoline, or to those blended with alkylate (JP-A-3-93894). No.), gasoline obtained by blending MTBE with a gasoline base material having a specific distillation property and component composition (Japanese Patent Laid-Open No. 3-263493), butane-butene fraction, aliphatic hydrocarbon component and aromatic carbonization A fuel oil composition (JP-A-3-229796) having a research octane number of 105 or more obtained by adding MTBE to a base oil in which a hydrogen component is blended at a certain ratio is known.
However, increasing the amount of MTBE in order to increase the octane number of gasoline, NO _x reduction and exhaust gas mileage by density reduction is increased. In addition, catalytic cracked gasoline, which is one of the main base materials of gasoline, has a higher sulfur content than other base materials, which leads to an increase in SO _x in the exhaust gas. In addition, when the sulfur content in gasoline is large, the activity of the three-way catalyst decreases due to poisoning of the catalyst, and as a result, NO _x in the exhaust gas increases.
In this way, all of the unleaded high octane gasoline blended with MTBE that has been proposed so far aims to improve the octane number and operability, and the amount of NO _x and SO _{x in} the exhaust gas can be reduced. It was inadequate and not always satisfactory from the viewpoint of pollution prevention.
In addition, when gasoline contains a large amount of benzene, the gasoline itself adversely affects the human body, and the exhaust gas contains a large amount of benzene, resulting in environmental pollution.

Under such circumstances, the present invention is excellent in driving performance of automobiles such as high-speed knock resistance, acceleration, combustion, startability, and drivability, as well as benzene content in exhaust gas, NO _x , SO _x. It is an object of the present invention to provide a method for producing a fuel oil for gasoline engines with low pollution and low lead and high octane number.

As a result of intensive research to develop a fuel oil for a lead-free high-octane gasoline engine that has excellent driving performance and low pollution, the present inventors have a specific distillation property and the research method octane number of each fraction. Is a gasoline engine fuel oil having an exhaust gas index, a benzene content, and a sulfur content of not more than specific values, and having a research octane number in the range of 97 to 102. And found that it can be adapted to the purpose. The present invention has been completed based on such findings. That is, the present invention
A gasoline engine characterized by blending fuel oil for a gasoline engine that satisfies the following conditions using at least the remaining fraction obtained by removing the benzene fraction from the reformed gasoline, cracked gasoline, alkylate and isomerate It is a manufacturing method of the fuel oil.
(1) A fraction having a boiling point of 25 ° C. or more and less than 75 ° C. is 35 to 50% by volume, a fraction having a boiling point of 75 ° C. or more and less than 125 ° C. is 25 to 40% by volume, and a fraction having a boiling point of 125 ° C. or more and less than 175 ° C. 30% by volume, (2) the research octane number of each fraction is 80 or more, and (3) formula (I)
Y = 1.07BZ + 0.12TO + 0.11EB + 0.05XY + 0.03C 9 + A + 0.005 [100- (BZ + TO + EB + XY + C 9 + A) ]
... (I)
[In the formula, BZ is benzene content, TO is toluene content, EB is ethylbenzene content, XY is xylene content, C ₉ ⁺ A is aromatic content with 9 or more carbon atoms (both fuel oil The content is the volume%). ]
Exhaust gas index Y represented by the formula (5) is 5 or less, (4) benzene content is 1% by volume or less, and sulfur content is 40 ppm or less, and (5) research octane number is 97 to 102 There is

The fuel oil for gasoline engine of the present invention is excellent in driving performance of automobiles such as high-speed knock resistance, acceleration, combustion, startability, drivability and the like, benzene content in exhaust gas, NO _x , SO _x, etc. This is a low-pollution, low-lead, high-octane gasoline production method.

The fuel oil in the production method of the present invention is (1) as a distillation property, a fraction having a boiling point of less than 25 ° C is 3 to 10% by volume, a fraction having a boiling point of 25 ° C to less than 75 ° C is 35 to 50% by volume, and a boiling point is 75. The fraction having a boiling point of 125 ° C. or more and 25 ° C. or less is 25 to 40% by volume, the fraction having a boiling point of 125 ° C. or more and less than 175 ° C. is 10 to 30% by volume, and the fraction having a boiling point of 175 ° C. or more is 5% by volume or less.
When the fraction having a boiling point of less than 25 ° C. is less than 3% by volume, the startability is inferior. In addition, when the fraction having a boiling point of 25 ° C. or more and less than 75 ° C., the fraction having a boiling point of 75 ° C. or more and less than 125 ° C., and a fraction having a boiling point of 125 ° C. or more and less than 175 ° C. are within the above ranges, respectively, drivability and acceleration are achieved. It will be excellent. If any one of the values deviates from the above range, the drivability is lowered or the acceleration is lowered. Further, if the fraction having a boiling point of 175 ° C. or higher exceeds 5% by volume, the engine becomes dirty or the problem of oil dilution occurs.

In the fuel oil in the production method of the present invention, (2) the research method octane number (sometimes abbreviated as RON) of each fraction is 80 or more, preferably 85 or more. If this value is less than 80, a well-balanced anti-knock property cannot be obtained.
The distillation properties were determined by gas chromatography as described later, and the RON of each fraction was determined from the results of this gas chromatography method as described later.
Furthermore, (3) Formula (I)
Y = 1.07BZ + 0.12TO + 0.11EB + 0.05XY + 0.03C 9 + A
+0.005 [100- (BZ + TO + EB + XY + C 9 + A) ]
... (I)
[In the formula, BZ is benzene content, TO is toluene content, EB is ethylbenzene content, XY is xylene content, C ₉ ⁺ A is aromatic content with 9 or more carbon atoms (both fuel oil The content is the volume%). ]
The exhaust gas index Y represented by is 5 or less, preferably 4 or less, more preferably 3.5 or less. The index Y indicates the ratio of benzene contained in the exhaust hydrocarbon produced when the fuel oil is burned in the engine, and each coefficient is the benzene content (wt%) in the exhaust hydrocarbon / fuel oil. It is a value of content (volume%) of each component in the inside. That is, this value is the largest for benzene, and then decreases as the number of substituents on the benzene ring increases, such as monoalkylbenzene, dialkylbenzene, and trialkylbenzene. Paraffin and olefin are very small, 0.005, respectively. [100− (BZ + TO + EB + XY + C ₉ ⁺ A)] represents a component other than the aromatic component in the fuel oil. When the exhaust gas index Y represented by the above formula (I) exceeds 5, the exhaust gas cannot be sufficiently reduced in pollution.
In addition, content of each aromatic content is the value computed from the total composition analysis (based on Petroleum Institute method JPI-5S-90) by the gas chromatograph method.

In the fuel oil in the production method of the present invention, (4) the benzene content is 1.0% by volume, preferably 0.5% by volume or less, and the sulfur content is 40 ppm or less, preferably 30 ppm or less. If the benzene content exceeds 1.0% by volume, the fuel oil itself may adversely affect the human body, or the benzene content in the exhaust gas may increase, causing environmental pollution. When the sulfur content is more than 40 ppm, with SO _X in the exhaust gas increases, decreases the activity of the three-way catalyst by poisoning of the catalyst, it is possible to increase NO _X resulting exhaust gases. The sulfur content is a value measured by a microcoulometric titration method according to JIS K-2541.
Further, in the fuel oil in the production method of the present invention, (5) the research method octane number is in the range of 97 to 102, preferably 98 to 101.

  The fuel oil in the production method of the present invention is not particularly limited as long as it satisfies the above conditions (1) to (5), and the origin thereof is not particularly limited. It can prepare by mix | blending suitably so that conditions of this (1)-(5) may be satisfy | filled. Examples of the gasoline base material include light naphtha obtained by fractionating a naphtha fraction obtained by atmospheric distillation of crude oil, cracked gasoline obtained by catalytic cracking or hydrocracking, catalytic reforming, and the like. The remaining fraction obtained by removing the benzene fraction from the reformed gasoline by the method described later, polymerized gasoline obtained by olefin polymerization, alkylate obtained by adding (alkylating) a lower olefin to a hydrocarbon such as isobutane, Examples include isomerates obtained by isomerization of straight-chain lower paraffin hydrocarbons, de-n-paraffin oils, fractions of these specific ranges, and aromatic hydrocarbons.

Examples of the method for reducing the amount of benzene in the reformed gasoline (benzene 4 to 10% by volume) include, for example, [1] Changing the operating conditions of the catalytic reformer, [2] C _{6 in} the desulfurized heavy naphtha of the raw material. Removal method by distillation of the fraction, [3] Method of removing the benzene fraction from the reformed gasoline by distillation, [4] By catalytic reaction, the benzene content in the reformed gasoline is hydrotreated and converted to cyclohexane, Further, this is introduced into an isomerization apparatus to isomerize it into a high octane isomer, [5] A method in which the benzene content in the reformed gasoline is alkylated by a catalytic reaction and converted to a high octane alkyl aromatic content. And [6] The benzene content removed and separated by the method of [2] above is alkylated with FCC (fluidized catalytic cracker) off-gas containing a large amount of ethylene or the like to obtain a high-octane alkyl. And a method for converting the aromatics.
The method [1] is a method of lowering the reaction temperature, but the dehydrogenation reaction of C ₆ naphthene in the raw desulfurized heavy naphtha is rate-limiting, and the benzene content in the reformed gasoline is reduced to 4% by volume. In the method [2], even if the light fraction (mainly C ₆ ) in the raw desulfurized heavy naphtha is cut by about 45% by volume, The limit of benzene content is about 1.5% by volume. This is because benzene is produced from hydrocarbons having 7 or more carbon atoms. Therefore, the method [3] is suitable as a method for reducing the amount of benzene in reformed gasoline. This method is usually a method of removing the benzene fraction from the reformed gasoline using the first splitter and the second splitter, and the benzene content in the resulting debenzene reformed gasoline is about 0 to 0.5% by volume. Drop to. Further, the benzene content can be refined and used for petrochemical raw materials such as benzene products and raw materials such as cyclohexane and styrene monomers. Furthermore, if this benzene is alkylated, it can be converted to alkylbenzene such as toluene and xylene. Further, if cyclohexane is isomerized, it can be converted to methylcyclopentane.
The above methods [4] and [5] require the installation of a new treatment apparatus for the catalytic reaction, but there is no method for utilizing the extracted benzene content and the new fraction obtained from the apparatus. However, when it can be used as a gasoline production base or petrochemical raw material, it can be a more efficient benzene reduction method than the method [3].
In addition, there are hydrotreatment method of benzene fraction and benzene extraction method. Here, in the hydrotreating method of a benzene fraction, first, a fraction containing a benzene precursor is separated by distillation, the remaining fraction is subjected to a catalytic reformer, and the resulting reformate is introduced into a splitter and introduced into a splitter. And is saturated with hydrogen. Furthermore, the three components are blended again to make a mixed reformate. On the other hand, the benzene extraction method, by distillation hydrodesulfurization naphtha, separating the i-C ₅ ~n-C ₆ fraction is subjected to catalytic reforming apparatus 70 ° C. ⁺ fraction, C ₅ fraction with splitter, Separated into benzene toluene fraction (BT fraction) and reformate fraction. Of these, the BT fraction is introduced into an extractor and separated into benzene (B), toluene (T) and raffinate. Benzene is used in petrochemical feedstock, reformate high-boiling fraction as C ₅ fraction in a mixed reformate mixed with toluene and raffinate.

Next, the method [4] will be described in more detail. In this method, the reformed gasoline (reformate) is distilled to cut a light reformate fraction containing C ₅ and C ₆ fractions, and then hydrogenated to convert benzene in the fraction to cyclohexane. Further, this cyclohexane is introduced into an isomerization apparatus to ring-open to methylcyclopentane and n-hexane, and n-hexane is further converted to a higher octane isomer. This method can be broadly divided into two processes in which these reactions are carried out in a two-column system or a single-column system.
Among these, the outline of the two-column process is as follows. First, after the raw material oil and hydrogen are preheated by a heat exchanger, the temperature is raised in a heating furnace and introduced into a hydrogenation reaction tower (first reaction tower). Since the hydrogenation reaction tower is an exothermic reaction, the catalyst layer is cooled by hydrogen gas, and the reaction temperature is controlled. Since hydrogenolysis is suppressed by suppressing the temperature rise, the liquid yield can be increased. The treated oil exiting from the hydrogenation reaction tower is introduced into an isomerization reaction tower (second reaction tower) packed with a zeolite-based isomerization catalyst. Since the second reaction column is operated at substantially the same temperature as the first reaction column, no heat exchanger is required. The reaction product leaving the isomerization reaction tower is sent to the separation tower for gas-liquid separation. Hydrogen is recycled to the reaction tower, the liquid phase is sent to the stabilizer, and the off-gas is separated.
Next, in the one-column process, since the hydrogenation reaction and the isomerization reaction are carried out in the same reaction column, the temperature control is performed with great care. Cooled hydrogen is supplied to each stage of the reaction tower. The downstream portion has almost the same configuration as the above-described two-column process. In either method, the reaction conditions (temperature, pressure) applied to the normal isomerization reaction are performed under mild conditions, and both use hydrogen generated in catalytic reforming.
In the method [4] above, the hydrogenation reaction catalyst used therefor is a platinum / alumina system, regardless of whether it is a two-column or single-column process, and is highly active and stable. The yield is high. The isomerization reaction catalyst is a zeolite-based catalyst and is passed through oil at almost the same temperature as the hydrogenation reaction. Therefore, the heat exchange and cooling system are simplified, the construction cost is low, and it is economical. In addition, it is possible to extend the life of the catalyst under mild operating conditions. One example of this operating condition, the pressure 29.6Atm (absolute pressure) the hydrogenation reaction, an inlet temperature of 180 to 250 ° C., carried out at a liquid hourly space velocity (LHSV) 4~6h ^r-1, pressure isomerization It can be carried out at 29.6 atm (absolute pressure), an inlet temperature of 240 to 270 ° C, and a liquid hourly space velocity (LHSV) of ¹ to 3 hr ^-1 .
If the benzene content is simply reduced, it can be efficiently converted to cyclohexane by hydrotreating a C _{5 to} C ₆ fraction having a benzene concentration of 30% by volume or less using various noble metal catalysts. , Side reactions can be suppressed as much as possible.

Next, the method [6] will be described in more detail. This method is roughly divided into the following two methods, Method I and Method II.
First, in Method I, a reformate fraction of C ₅ or higher is first separated by distillation into a C ₅ fraction, a benzene-containing fraction, and a C ₇ ⁺ heavy reformate three fraction. The FCC off gas is washed with an amine to remove hydrogen sulfide, and then immediately introduced into a benzene reduction device (for example, MBR device manufactured by Mobil Corporation). The FCC offgas is mostly ethylene but contains about 5-10% propylene. Note that a ZSM-5 catalyst is used for the benzene reduction apparatus, and a fluidized bed type reaction tower and a slip stream type regenerator are combined. Half of the diluted benzene introduced is alkylated to produce a high octane alkylbenzene. Alkylation of diluted benzene is suitable for the use of ethylene, and there is no problem even if C _{5 to} C ₇ olefins coexist. Due to alkylation of benzene, an increase in octane number is observed with respect to the decrease in benzene.
Next, in Method II, when a cyclic C ₆ compound that is a benzene precursor is supplied to the catalytic reformer, benzene is synthesized from cyclohexane or methylcyclopentane. Therefore, it is necessary to place a naphtha splitter in advance and side-cut the benzene precursor. In Method II, the side-cut cyclic C ₆ compound bypasses the catalytic reformer and is introduced into the benzene reduction unit. Since most of the cyclic C ₆ fraction is removed from the reforming feed, the low octane number light reformate is slightly reduced and the C ₅ ⁺ reformate benzene is increased to about 10% by volume. The light reformate is also separated by a stripper and introduced into a benzene reduction apparatus. This method reduces the amount of hydrogen produced from the catalytic reformer, but this reduction is less than the amount of hydrogen used in the process of saturating benzene. By bypassing the annular C ₆ fraction, reformate benzene consists 1/2 3/4 less, residual benzene is alkylated by FCC olefin gas with benzene reduction device. At the same time, the benzene reduction apparatus decomposes C ₆ ⁺ straight-chain paraffin having an extremely low octane number and distills it together with cyclic C ₆ fraction and reformate benzene. Linear C ₆ fraction is decomposed propane, butane and light olefins. Most of the light olefin produced is converted to gasoline. The conversion of FCC offgas ethylene and propylene to ethylbenzene and cumene is high, and alkylation of benzene and decomposition of C ₆ ⁺ paraffins greatly increases research and motor octane numbers. According to this method, it is possible to relax constraints such as excessive generation of FCC off-gas fuel or insufficient propylene content in the FCC gas plant. By adopting this, the operating conditions of the FCC are made more severe. It is possible.
Furthermore, as a modification of these, a benzene alkylation process in which a light olefin (for example, propylene) is mixed and reacted with a benzene-rich fraction is reacted between a separator and a stabilizer of an existing fixed bed reformer. Benzene can be reduced.

Also, FCC (fluidized cracking cracker) gasoline (benzene 0.9-1.6 vol%), light FCC gasoline (benzene 1-2 vol%) and desulfurized heavy naphtha (benzene 0.9-1.3 vol%) %) Is usually used without debenzene treatment from the viewpoint of economy, but of course, it may be used after debenzene treatment. In this case, the amount of benzene in FCC gasoline can be reduced by, for example, controlling the feedstock and operating conditions, and the amount of benzene in light FCC gasoline can be reduced by reducing the cut temperature during FCC gasoline fractionation. Can be done by control.
In addition, the benzene content of desulfurized heavy naphtha can be reduced by reducing the amount of naphthenic crude oil mixed.

Next, in order to suppress the sulfur content in the fuel oil in the production method of the present invention to 40 ppm or less, it is important to reduce the sulfur content in the catalytic cracked gasoline having a particularly high sulfur content in the gasoline base material. . For this purpose, the catalytic cracking feedstock is desulfurized by hydrogenation treatment, passed through a catalytic cracking device, and the produced catalytic cracked gasoline is introduced into a desulfurization device such as a Marrox device for desulfurization. preferable.
The fuel oil in the production method of the present invention satisfies the conditions (1) to (5) and usually has the following composition and properties. That is, the content of oxygenated compounds such as MTBE, methyl tertiary amyl ether (MTAE), ethyl tertiary butyl ether (ETBE), ethyl tertiary amyl ether (ETAE) is usually 0 to 15% by volume, preferably 2 to 15% by volume. %, More preferably 4 to 10% by volume, and the aromatic content is 15 to 45% by volume, preferably 21 to 39% by volume, and the aromatic content having 9 or more carbon atoms is 10% by volume or less, Preferably, it is 8 volume% or less, the olefin content is 2 to 25 volume%, preferably 5 to 19 volume%, and the value of [Research Octane Number (RON) + Motor Method Octane Number (MON)] / 2 is 93 or more. , Preferably 94 or more, and the Reed vapor pressure is 0.4 to 0.8 kg / cm ² .

The oxygen-containing compound has an effect of improving the octane number. When the content exceeds 15% by volume, there is a tendency that NO _x in the engine exhaust gas increases. Further, when the aromatic content is less than 15% by volume, the octane number of the obtained fuel oil is not sufficiently improved, and when the oxygen-containing compound is added in a large amount in order to improve the octane number, the exhaust gas as described above. resulting in undesirable situations such as NO _X in is increased. Conversely, if it exceeds 45% by volume, the rubber of various devices used in the fuel system tends to deteriorate or harmful components in the exhaust gas tend to increase. Furthermore, when the content of aromatics having 9 or more carbon atoms in this aromatic content exceeds 10% by volume, the operability at an intermediate temperature (15 to 25 ° C.), particularly the acceleration responsiveness tends to decrease. It is done. The aromatic content is a value measured according to JIS K-2536, and the aromatic content with 9 or more carbon atoms is analyzed by gas chromatograph total composition analysis of gasoline (Japan Petroleum Institute method JPI-5S). -Based on -90).

Next, if the olefin content exceeds the above range, a problem arises in terms of the stability of the fuel oil. In addition, an olefin content here has a C4-C11 olefin as a main component normally. The olefin content is a value measured according to JIS K-2536.
If the value of (RON + MON) / 2 is less than 93, the high running knock resistance may be insufficient.
In addition, in order to suppress the aromatic content of 9 or more carbon atoms in fuel oil to 10% by volume or less, each gasoline base material is analyzed by gas chromatograph, and the aromatic content of 9 or more carbon atoms is determined. What is necessary is just to make it become 10 volume% or less. In this case, naturally, the above total composition analysis is performed so that the component composition and properties other than the aromatic component having 9 or more carbon atoms (for example, RON, distillation property, aromatic component, olefin component, etc.) are also in an appropriate range. Should be judged from Here, various specific methods for adjusting the aromatic content of 9 or more carbon atoms to 10% by volume or less can be considered, but the following methods (a) to (e) are preferable. Can be mentioned.

(A) Decreasing the content of aromatics having 9 or more carbon atoms in catalytically modified gasoline. For this purpose, (i) the raw material heavy naphtha is lightened by removing the heavy components, (ii) the heavy components are removed from the reformed gasoline, (iii) the operating conditions of the catalytic reformer are adjusted. There are methods such as.
(B) In preparing the fuel oil, the mixing ratio of the catalytic reforming gasoline is lowered.
(C) Lightening by removing heavy components from catalytic cracked gasoline.
(D) Do not use aromatics having 9 or more carbon atoms after extracting BTX (benzene, toluene, xylene) as petrochemical raw material from reformed gasoline.
(E) Use toluene instead of reformed gasoline.

Various additives can be appropriately blended in the fuel oil in the production method of the present invention as necessary.
Examples of such additives include phenolic and amine antioxidants, metal deactivators such as Schiff compounds and thioamide compounds, surface ignition inhibitors such as organophosphorus compounds, succinimides, poly Detergents such as alkylamines and polyetheramines, anti-icing agents such as polyhydric alcohols and ethers, organic acid alkali metal and alkaline earth metal salts, auxiliary alcohols such as higher alcohol sulfates, anionic surfactants Antistatic agents such as cationic surfactants and amphoteric surfactants, rust inhibitors such as esters of alkenyl succinic acid, discriminating agents such as kilyzanine and coumarin, odorants such as natural essential oils and synthetic fragrances, azo dyes, etc. Known fuel oil additives such as colorants can be mentioned, and one or more of these can be added. Further, the addition amount of these additives may be appropriately selected according to the situation, but it is usually desirable that the total amount of the additive is 0.1% by weight or less of the fuel oil. Moreover, it is also possible to mix and use an engine oil for a two-cycle engine by a commonly practiced method.

Furthermore, although an Example demonstrates this invention in detail, this invention is not restrict | limited at all by these examples.
The properties and performance of the fuel oil were determined according to the following method.
[Properties of fuel oil]
(1) Octane number Measured according to JIS K-2280.
(2) Sulfur content Measured by a microcoulometric titration method according to JIS K-2541.
(3) Distillation properties (1)
Obtained in accordance with JIS K-2254.
(4) Total composition gas chromatograph method According to the Petroleum Institute method JPI-5S-90, each hydrocarbon content in fuel oil is calculated | required. Since the value is close to% by weight, it is converted from each hydrocarbon density to volume%. Each component by this analysis method comes out in order of boiling point.
(I) Distillation properties (2)
The amount (volume%) of each component corresponding to a boiling point less than 25 ° C. is integrated and calculated. Similarly, the amount of each component corresponding to each temperature range is integrated and calculated to obtain the distillation property (2).
(B) RON of each fraction
The product of RON and the amount (volume%) of each component corresponding to a boiling point of less than 25 ° C. is integrated, and this is divided by the integrated amount (volume%) to obtain the RON of the fraction having a boiling point of less than 25 ° C. Similarly, the RON of the fraction in each temperature range is obtained.
In general, the RON of the mixture is higher than the simple integration RON. This difference is called a blend bonus (or octane bonus), but was ignored here.
(C) Benzene, toluene, ethylbenzene, xylene, aromatic content of 9 or more carbon atoms The gas chromatographic analysis value is used.
(5) Composition Measured according to JIS K-2536.

[Performance of fuel oil]
(1) Driving performance at intermediate temperature Using an EFI specification automobile engine, the engine was accelerated from 700 rpm at room temperature (20 ° C.) and evaluated in terms of time (seconds) until reaching 2500 rpm. The shorter this time, the better the acceleration response of the fuel. Here, the arrival time is expressed in% based on the result of Example 1.
(2) Benzene Concentration in Exhaust Gas Benzene in exhaust gas was analyzed according to the method described in SAE Paper 920320 according to “Gasoline automobile idling, 11-mode exhaust gas test method” of TRIAS 23-1991.

Examples 1 and 2 and Comparative Examples 1 to 4
A gasoline base material having the properties shown in Table 1 and MTBE were mixed at a ratio shown in Table 2 to prepare a fuel oil, and its properties and performance were determined. The results are shown in Table 2.

Claims (8)

A gasoline engine characterized by blending fuel oil for a gasoline engine that satisfies the following conditions using at least the remaining fraction obtained by removing the benzene fraction from the reformed gasoline, cracked gasoline, alkylate and isomerate Method for manufacturing fuel oil.
(1) A fraction having a boiling point of 25 ° C. or more and less than 75 ° C. is 35 to 50% by volume, a fraction having a boiling point of 75 ° C. or more and less than 125 ° C. is 25 to 40% by volume, and a fraction having a boiling point of 125 ° C. or more and less than 175 ° C. 30% by volume, (2) the research octane number of each fraction is 80 or more, and (3) formula (I)
Y = 1.07BZ + 0.12TO + 0.11EB + 0.05XY + 0.03C 9 + A + 0.005 [100- (BZ + TO + EB + XY + C 9 + A) ] · · · (I)
[In the formula, BZ is benzene content, TO is toluene content, EB is ethylbenzene content, XY is xylene content, C ₉ ⁺ A is aromatic content with 9 or more carbon atoms (both fuel oil The content is the volume%). ]
Exhaust gas index Y represented by the formula (5) is 5 or less, (4) benzene content is 1% by volume or less, and sulfur content is 40 ppm or less, and (5) research octane number is 97 to 102 There is   The method for producing fuel oil for gasoline engine according to claim 1, wherein the aromatic content of the fuel oil for gasoline engine is 15 to 45% by volume.   The method for producing fuel oil for gasoline engines according to claim 1 or 2, wherein the content of aromatics having 9 or more carbon atoms in the fuel oil for gasoline engines is 10% by volume or less.   The manufacturing method of the fuel oil for gasoline engines in any one of Claims 1-3 which makes the sulfur content of the fuel oil for gasoline engines 30 ppm or less.   The method for producing a fuel oil for a gasoline engine according to any one of claims 1 to 4, wherein the olefin content in the fuel oil for a gasoline engine is 2 to 25% by volume.   The method for producing a fuel oil for a gasoline engine according to any one of claims 1 to 5, wherein the oxygen-containing compound content of the fuel oil for a gasoline engine is 0 to 15% by volume. Method for manufacturing a fuel oil for gasoline engines according to any one of claims 1 to 6 the Reid vapor pressure of the fuel oil for gasoline engines 0.4~0.8kg / cm ^2.   The method for producing a fuel oil for a gasoline engine according to any one of claims 1 to 7, wherein the benzene content of the fuel oil for a gasoline engine is 0.5 vol% or less.