JP2009293047A - Method for producing unleaded gasoline composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an unleaded gasoline composition with reduced sulfur content and assuring satisfactory driving performance. <P>SOLUTION: The gasoline composition has an octane value of 96.0 or more according to the research method, 50 vol.% distillation temperatures at 105°C or lower, olefin content of 10 vol.% or more, a total sulfur content of 1 ppm by mass or less, thiophene as sulfur of 0.1-1.0 ppm by mass, and thiophene in total sulfur content as sulfur of 65-100 mass%. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an unleaded gasoline composition with reduced environmental impact and a method for producing the same. In particular, the present invention relates to an unleaded gasoline composition that secures sufficient operating characteristics while reducing the influence on the environment by reducing the sulfur content and ensuring a high octane number, and a method for producing the same.

  In recent years, the demand for high-performance gasoline having high driving performance has increased with the improvement in performance of automobiles. On the other hand, environmental pollution due to automobile fuel and its combustion exhaust gas has become a social problem. Therefore, an automobile fuel that maintains high driving performance and has a low environmental impact is desired. In particular, further reduction of sulfur content is desired from the viewpoint of exhaust gas purification and fuel efficiency improvement.

  JIS K 2202 stipulates No. 1 automobile gasoline with a research octane number (RON) of 96.0 or more and No. 2 automobile gasoline with 89.0 or more. The former is a high-performance premium gasoline and the latter is regular. Commercially available as gasoline. Conventionally, premium gasoline has more than 93 such as catalytically modified gasoline base, base with more than 100 RON such as methyl-t-butyl ether (MTBE), alkylate gasoline base, catalytic cracked gasoline base Manufactured by blending various base materials, mainly base materials with RON.

  The catalytic cracking gasoline base produced by catalytic cracking of a heavy petroleum fraction has an advantage that it can be produced economically compared with other premium gasoline bases, but contains a large amount of sulfur. As a result, most of the sulfur content in the premium gasoline produced as described above is derived from the catalytic cracked gasoline base material.

  The sulfur content of the catalytic cracking gasoline base can be easily reduced by a known technique of hydrotreating in the presence of high-pressure hydrogen and a catalyst. However, in that case, a large amount of catalytic cracking gasoline base material is contained, and the olefin content having high RON is hydrogenated to lower the base material RON. There was a problem that it could not be obtained. An environment-friendly gasoline having a sulfur content as low as 1 mass ppm or less and sufficient practical performance, and a method for producing the same have not yet been established.

  An object of the present invention is to provide an unleaded gasoline composition and a method for producing the same, in which the sulfur content is reduced and sufficient operating characteristics are ensured under such circumstances.

  As a result of diligent research to solve the above problems, the present inventors use only a specific fraction of catalytic cracking gasoline base material, and use a base material that has been subjected to desulfurization treatment of the fraction. The inventors have conceived an unleaded gasoline composition and a method for producing the same that maintain RON while reducing sulfur content and ensuring sufficient operation characteristics.

That is, the method for producing an unleaded gasoline composition having a sulfur content of 1 mass ppm or less and a research octane number of 96.0 or more according to the present invention is as follows:
(1) a first step of fractionating the catalytic cracking oil to obtain a catalytic cracking light fraction having a 5% by volume distillation temperature of 25-43 ° C and a 95% by volume distillation temperature of 55-100 ° C;
(2) a second step for obtaining a desulfurized light fraction by desulfurizing the catalytic cracking light fraction obtained in the first step; and (3) a desulfurized light fraction obtained in the second step and another gasoline group. A third step of mixing the material, preferably another gasoline base with a sulfur content of 0.5 ppm or less.

  In the third step, it is preferable to mix 10 to 45% by volume of the desulfurized light fraction and 90 to 55% by volume of another gasoline base. In the second step, it is preferable to perform a desulfurization treatment by contacting a porous desulfurization agent containing at least one selected from copper, zinc, nickel and iron with a catalytically cracked light fraction, or an extraction solvent is used. It is preferable to desulfurize the catalytic cracking light fraction by an extraction treatment. Furthermore, the thiophene content of the catalytically cracked light fraction obtained in the first step is preferably 2.5 ppm by mass or less as the sulfur content, and before performing the fractional distillation in the first step, the catalytically cracked oil is previously obtained. On the other hand, it is preferable to perform a pretreatment for increasing the molecular weight of the contained sulfur compound.

  The lead-free gasoline composition according to the present invention has a research octane number of 96.0 or more, a 50% by volume distillation temperature of 105 ° C. or less, an olefin content of 10% by volume or more, and a thiophene ratio in the total sulfur content of sulfur. The amount is 50% by mass or more.

  In the unleaded gasoline composition of the present invention, the total sulfur content is preferably 1 mass ppm or less, and the olefin content in the boiling range of 35 to 80 ° C. in the total olefin content is preferably 90% by volume or more. Further, the benzene content is preferably 0.3% by volume or less.

  The present invention is particularly a method for producing an unleaded gasoline composition using a desulfurized light fraction of catalytic cracked oil that has been desulfurized while leaving the high-octane olefin content as it is, and therefore has a very low sulfur content and sufficient operating characteristics. An unleaded gasoline composition having the following can be obtained. Therefore, according to the present invention, an unleaded gasoline composition that has a sufficient driving characteristic and is environmentally friendly is provided, since it is a lead-free gasoline composition that has a particularly high sulfur content in the total sulfur content and a very low sulfur content. Is done.

[First step]
In the first step in the method for producing an unleaded gasoline composition of the present invention, the catalytically cracked oil is fractionally distilled to give a 5% by volume distillation temperature of 25.0 to 43.0 ° C, preferably 35.0 to 43.0 ° C. And a catalytically cracked light fraction having a 95% by volume distillation temperature of 55.0 to 100.0 ° C, preferably 55.0 to 80.0 ° C. When the 5% by volume distillation temperature is less than 25.0 ° C, the vapor pressure of the unleaded gasoline composition increases. On the other hand, when the 95% by volume distillation temperature exceeds 100.0 ° C. in particular, the sulfur content of the desulfurized light fraction increases or the RON of the gasoline base material decreases to prepare a desired unleaded gasoline composition. Becomes difficult. If the 5% by volume distillation temperature exceeds 43.0 ° C. or the 95% by volume distillation temperature is less than 55.0 ° C., it is difficult to adjust the distillation properties of the unleaded gasoline composition. The yield of the catalytically cracked light fraction obtained is lowered and the cost of the unleaded gasoline composition is increased.

  The thiophene content of the catalytically cracked light fraction obtained in the first step is preferably 0.1 to 2.5 ppm by mass as the sulfur content. It is still more preferable that it is 0.1-2.0 mass ppm, Furthermore, it is 0.1-1.0 mass ppm. Since thiophene is one of the sulfur compounds most likely to remain in the desulfurized light fraction obtained by the desulfurization treatment in the second step, the catalytically cracked light fraction obtained in the first step has a sulfur content of 2. If thiophene exceeding 5 ppm by mass is contained, the sulfur content is not removed by the desulfurization treatment in the second step, and the flexibility to be mixed with another gasoline base in the next third step is not preferable. In addition, it is preferable that the catalytic cracking light fraction obtained in the first step contains only thiophene having a sulfur content of less than 0.1 ppm by mass because the yield of the catalytic cracking light fraction is reduced. Absent.

  It is preferable that 2-methylthiophene and 3-methylthiophene contained in the catalytically cracked light fraction obtained in the first step have a total sulfur content of 0.5 mass ppm or less. Similarly to thiophene, 2-methylthiophene and 3-methylthiophene are sulfur compounds that are most likely to remain in the desulfurized light fraction obtained by the desulfurization treatment in the second step. Therefore, in the first step, it is preferable to reduce 2-methylthiophene and 3-methylthiophene, and it is more preferable that the total sulfur content is 0.1 mass ppm or less. For this purpose, the 95% distillation temperature during fractional distillation is preferably 75.0 ° C. or lower, particularly preferably 70.0 ° C. or lower.

[Catalytic cracked oil]
The process for producing the catalytic cracking oil used in the first step does not particularly limit the catalytic cracking apparatus, the raw material oil, and the operating conditions, and any known production process can be adopted. The catalytic cracking unit uses a catalyst such as amorphous silica alumina, zeolite, etc., in addition to petroleum fractions from light oil to vacuum gas oil, while being obtained from heavy oil indirect desulfurization unit, it can be obtained directly from degassing oil or heavy oil direct desulfurization unit. This is a device that mainly obtains a high octane gasoline base by catalytically cracking degassed oil and atmospheric residue oil. Examples of the catalytic cracking process include fluid catalytic cracking methods such as UOP catalytic cracking method, flexi cracking method, ultra ortho flow method, texaco fluid catalytic cracking method, RCC method, etc. Examples thereof include a residual oil fluid catalytic cracking method such as the HOC method.

  In order to reduce thiophene in the catalytic cracking light fraction, it is preferable to use the above petroleum fraction from light oil to vacuum gas oil as the feedstock of the catalytic cracking device, particularly those having a sulfur content of 2,000 ppm or less, Further, it is preferable to use a fraction reduced to 1,000 ppm or less, particularly 500 ppm or less by hydrorefining or the like.

[Pretreatment to increase the molecular weight of sulfur compounds]
About the catalytic cracking oil provided to a 1st process, it is preferable to perform the pretreatment which enlarges the molecular weight of the sulfur compound contained, and to use for a 1st process. By selectively increasing the molecular weight of the sulfur compound such as thiols, the boiling point of the sulfur-containing compound is increased. Therefore, in the first step, the sulfur-containing compound is unevenly distributed in the heavy fraction and removed. And the sulfur content of the catalytically cracked light fraction obtained in the first step can be reduced. Specifically, it is more preferable that the total content of thiols and thiols in the catalytically cracked light fraction is 0.1 mass ppm or less as a sulfur content by the method described later.

  Conventionally, in petroleum refining, sweetening for treating thiols to make the product non-brominated is performed, but a known method for converting thiols to disulfides by an oxidation method or an oxidation extraction method is the present invention. Can be applied as a method of increasing the molecular weight of the sulfur compound. Specifically, the Marlox method, the doctor method, and the like disclosed in publicly known documents (Sangyo Tosho Co., Ltd., Petroleum Refining Technology Handbook 3rd Edition, 1981) are preferably used.

  In the present invention, as a method of increasing the molecular weight of the sulfur compound, a method of reacting the sulfur compound contained in the naphtha fraction with olefins is also preferably used. Specifically, a method of reacting a thiol with an olefin disclosed in a published patent publication (Japanese Patent Laid-Open No. 2001-55584) or a known document ("Production of Low Sulfur Gasoline and Diesel Fuels: Tier 2 and Beyond" , Petroleum Refining Technology Seminar August 2001, 11-18), and a method of reacting thiols and thiophenes with olefins.

[Second step]
In the second step in the method for producing an unleaded gasoline composition of the present invention, the catalytic cracking light fraction obtained in the first step is desulfurized to obtain a desulfurized light fraction to be used in the third step. The sulfur content of the desulfurized light fraction obtained in the second step is preferably desulfurized to 3 ppm by mass or less, more preferably 2 ppm by mass or less, and even more preferably 1 ppm by mass or less. The olefin content of the desulfurized light fraction is preferably 20 to 50% by volume, particularly 25 to 45% by volume.

  The method of the desulfurization treatment in the second step is not particularly limited, but the sulfur compound is selected from the catalytic cracking light fraction by the method of contacting the desulfurizing agent having adsorption or sorption function with the sulfur compound and the catalytic cracking light fraction. The method of removing it automatically is mentioned as a preferable method. There is also a method of hydrodesulfurizing catalytic cracking light fractions in the presence of a desulfurization catalyst and hydrogen, but in the presence of high-pressure hydrogen, olefins are likely to be hydrogenated and the resulting gasoline base RON is reduced. It's easy to do. Therefore, the desulfurization treatment is preferably performed in a state where hydrogen is not substantially present or in a hydrogen partial pressure of less than 1 MPa.

The desulfurizing agent in the case of using the method of contacting the catalytically cracked light fraction with the desulfurizing agent having an adsorption or sorption function is not particularly limited as long as it has an adsorption or sorption function for sulfur compounds. For example, a porous desulfurization agent containing at least one metal component selected from copper, zinc, nickel and iron is preferably used. A preferable desulfurizing agent contains 0.5 to 85% by weight, particularly 1 to 80% by weight of the metal component such as copper. The method for producing the desulfurizing agent is not particularly limited, but a metal component such as copper and a component such as aluminum by a production method or a coprecipitation method in which a porous carrier such as alumina is impregnated with a metal component such as copper and supported. A preferable method is a production method in which the above is precipitated and subjected to steps such as molding and baking. Alternatively, the molded and fired desulfurizing agent may be further impregnated and supported with a metal component and fired. As the desulfurization agent, the fired one may be used as it is, or it may be used after being reduced in a hydrogen atmosphere. The specific surface area of the desulfurizing agent, ^{50 m} 2 / g or more, and particularly preferably is 100 m ² / g, even at 200~600m ² / g. The composition and production method of the desulfurizing agent are not particularly limited, but specific examples include desulfurizing agents as disclosed in Japanese Patent No. 3324746, Japanese Patent No. 3230864, and JP-A-11-61154.

The desulfurization treatment may be performed batchwise or flow-through, but the desulfurization obtained with the desulfurization agent is performed by circulating the catalytically cracked light fraction through a fixed-bed desulfurization tower filled with a desulfurization agent. This is preferable because the light fraction can be easily separated. The temperature for the desulfurization treatment can be selected from the range of 15 to 400 ° C, preferably 80 to 380 ° C. In order to promote desulfurization of thiophenes that are not easily desulfurized only by contacting with a desulfurizing agent, desulfurization treatment may be performed in the presence of hydrogen. However, the hydrogen partial pressure is preferably less than 1 MPa, and more preferably less than 0.6 MPa in order to avoid hydrogenation of the olefin and a decrease in RON of the resulting gasoline base material. When the desulfurization treatment is performed by bringing the desulfurizing agent and the catalytic cracking light fraction into contact with each other in a fixed bed flow type, the LHSV is preferably selected from the range of 0.01 to 10,000 h ⁻¹ .

  As a method for selectively removing sulfur compounds from a catalytically cracked light fraction by extraction, Japanese Patent Laid-Open No. 2003-531922 and 21st JPI Petroleum Refining Conference “Recent Progress in Petroleum Process Technology”, 159 (2002) have been proposed. A typical UOP Sulfur-X (registered trademark) process or the like can be used as a solvent extraction process or a solvent extraction process. Examples of solvents used in these processes include sulfolane, 3-methyl sulfolane, 2,4-dimethyl sulfolane, 3-ethyl sulfolane, diethylene glycol, triethylene glycol, tetraethylene glycol, N-methyl-2-pyrrolidone. N-ethyl-2-pyrrolidone, N-propyl-2-pyrrolidone, N-formylmorpholine, dimethyl sulfoxide, diethyl sulfoxide, methyl ethyl sulfoxide, dipropyl sulfoxide, ethylene carbonate, propylene carbonate and the like. These solvents may be used by mixing with water for easy handling. Especially for solvents that can extract thiophene sulfur compounds, benzene having a molecular structure similar to the thiophene ring can be extracted at the same time, so the catalytically cracked light fraction obtained by extraction is a fraction with a low benzene content. It becomes. Therefore, an unleaded gasoline composition containing a catalytically cracked light fraction in which the amount of sulfur compounds is reduced by solvent extraction can also reduce the benzene content as compared with the prior art.

[Other gasoline base materials used in the third step]
Other gasoline base materials mixed in the third step include catalytic reformed gasoline base materials, alkylate gasoline base materials, base materials obtained by desulfurizing straight-run naphtha, and MTBE, ethyl-t-butyl ether (ETBE), Known gasoline base materials such as oxygen-containing gasoline base materials such as t-amyl ethyl ether (TAEE), ethanol, and methanol can be used. If the sulfur content of the unleaded gasoline composition obtained by mixing with the gasoline base material obtained from the second step is 1 mass ppm or less, the sulfur content of the other gasoline base material mixed in the third step It is not limited. Preferably, the sulfur content is 0.5 mass ppm or less, and further 0.1 mass ppm or less. If the sulfur content of the other gasoline base exceeds 0.5 ppm by mass, the blending amount of the gasoline base obtained from the second step is restricted, which is not preferable.

  Preferred blending amounts include, for example, 10 to 45% by volume of desulfurized light fraction, especially 25 to 40% by volume, 25 to 50% by volume of catalytic reformed gasoline base, particularly 30 to 45% by volume, alkylate gasoline. The substrate may be blended in an amount of 10 to 40% by volume, particularly 15 to 30% by volume.

[Unleaded gasoline composition]
The unleaded gasoline composition of the present invention has a research octane number of 96.0 or more, preferably 98 to 102, 50 volume% distillation temperature of 105 ° C. or less, preferably 80 to 100 ° C., olefin content of 10 volume% or more, Preferably, 10 to 20% by volume, and the proportion of thiophene in the total sulfur content is 65 to 100% by mass as the sulfur content. Further, the total sulfur content is preferably 1 ppm by mass or less, and the ratio of the olefin content in the boiling range of 25 to 100 ° C. in the total olefin content is preferably 90% by volume or more. If the proportion of olefins in the boiling point range 25-100 ° C., especially 35-80 ° C., is less than 90% by volume, the proportion of light olefins having a high octane number will decrease and satisfactory performance will be obtained. It becomes impossible. It is preferable to contain 0.1-1.0 mass ppm of thiophene in an unleaded gasoline composition as a sulfur content. Since thiophene is one of the sulfur compounds most likely to remain in the base material, it is not preferable to make thiophene less than 0.1 ppm by mass because the cost of the unleaded gasoline composition of the present invention increases.

[Other ingredients]
Furthermore, the gasoline composition of the present invention may contain one or more fuel oil additives known in the art as needed. Although these compounding quantities can be selected suitably, it is preferable to maintain the total compounding quantity of an additive to 0.1 weight% or less normally. Examples of fuel oil additives that can be used in the gasoline of the present invention include phenolic, amine-based antioxidants, Schiff-type compounds, metal deactivators such as thioamide-type compounds, and organic phosphorus-based surfaces. Anti-ignition agent, detergent / dispersant such as succinimide, polyalkylamine, polyetheramine, anti-icing agent such as polyhydric alcohol or its ether, alkali metal salt or alkaline earth metal salt of organic acid, sulfuric acid of higher alcohol Examples include an auxiliary combustor such as an ester, an anionic surfactant, a cationic surfactant, an antistatic agent such as an amphoteric surfactant, and a colorant such as an azo dye.

  The present invention will be described in more detail based on the following examples, but the present invention is not limited to the following examples.

Preparation of desulfurized light fraction 1
Catalytic cracked oil A1 obtained by fluidized bed catalytic cracking using a hydrorefined gas oil fraction of Middle Eastern crude oil as the main feed oil is oxidized and extracted (sweetened) to obtain catalytic cracked oil B1. It was. The catalytic cracking oil B1 was fractionated to remove light and heavy components to obtain a catalytic cracking light fraction C1. Table 1 shows the properties of the catalytic cracking oil A1, the catalytic cracking oil B1, and the catalytic cracking light fraction C1.

  The density was measured according to JIS K 2249, the vapor pressure was measured according to JIS K 2258, and the distillation property was measured according to JIS K 2254. The sulfur content was measured by the microcoulometric titration method of JIS K2541. The content of sulfur compounds (in terms of sulfur) was measured by gas chromatography using a Shimadzu gas chromatograph equipped with an ANTEK sulfur chemiluminescence detector that selectively detects and quantifies sulfur compounds by chemiluminescence. . The hydrocarbon component composition, benzene content, and RON were measured by a gas chromatograph method using a PIONA apparatus manufactured by Hured Packard.

  30 mL of this catalytic cracking light fraction C1 was stirred and mixed in a flask at room temperature for 24 hours with 10 g of a copper oxide-alumina-based desulfurization agent (containing 7.6 mass% of copper as a metal atom). The desulfurizing agent was filtered off to obtain a desulfurized light fraction D1. The light thiols contained in the catalytic cracking oil A1 were converted to higher molecular weight disulfides by oxidative extraction treatment. Although the catalytic cracking light fraction C1 contained a sulfur content of 5.6 mass ppm, a desulfurized light fraction D1 having a sulfur content of 0.8 mass ppm was obtained by treatment with a desulfurizing agent. The obtained desulfurized light fraction D1 contained 0.8 mass ppm of thiophene, but did not contain 2-methylthiophene and 3-methylthiophene.

Preparation of desulfurized light fraction 2
A catalytic cracking light fraction C2 having a property different from that of the catalytic cracking light fraction C1 is treated in the same manner as in Preparation 1 of the desulfurized light fraction except that a vacuum gas oil fraction of Middle East crude oil in another lot is used. Got. 200 mL of this catalytic cracking light fraction C2 was stirred and mixed in a flask for 2 hours at room temperature with 15 g of a copper oxide-alumina desulfurization agent (containing 7.6% by mass of copper as a metal atom). The desulfurization agent was filtered off to obtain a desulfurized light fraction D2. Properties of the catalytic cracking light fraction C2 and the desulfurized light fraction D2 are shown in Table 2. The catalytic cracking light fraction C2 contained 6.4 ppm by mass of sulfur, but by treating with a desulfurizing agent, a desulfurized light fraction D2 having a sulfur content of 1.6 ppm by mass was obtained. The obtained desulfurized light fraction D1 contained 1.6 ppm by mass of thiophene, but did not contain 2-methylthiophene and 3-methylthiophene.

Preparation of desulfurized light fraction 3
Further, using a hydrorefined portion of the vacuum gas oil fraction of a Middle Eastern crude oil in another lot, the same process as in the preparation 1 of the desulfurized light fraction was performed by fluidized bed catalytic cracking to obtain a catalytic cracked oil A3. Subsequently, it was oxidized and extracted (sweetened) to obtain catalytic cracking oil B3, which was further fractionated to obtain catalytic cracking light fraction C3. The catalytic cracking light fraction C3 (150 mL) was stirred and mixed in a flask for 1 hour at room temperature with 600 mL of sulfolane containing 5% by weight of water for extraction treatment. 100 mL of raffinate (not extracted with sulfolane) was washed with 100 mL of water to obtain a desulfurized light fraction D3. Table 3 shows properties of the catalytic cracking oil A3, the catalytic cracking oil B3, the catalytic cracking light fraction C3, and the desulfurized light fraction D3.

  The catalytic cracking light fraction C3 contained 7.6 ppm by mass of sulfur, but a desulfurized light fraction D3 having a sulfur content of 1.3 mass ppm was obtained by extraction treatment. The obtained desulfurized light fraction D3 contained 1.3 mass ppm of thiophene, but did not contain 2-methylthiophene and 3-methylthiophene. Further, the catalytic cracking light fraction C3 contained 1.4% by volume of benzene, but it was reduced to 0.3% by volume or less in the desulfurized light fraction D3 by the extraction treatment.

Preparation of unleaded gasoline composition An unleaded gasoline composition was prepared by mixing the desulfurized light fraction obtained as described above with another gasoline base. As other gasoline base materials, desulfurized naphtha G obtained by a known technique other than catalytic cracking, catalytic reforming medium oil H, catalytic reforming heavy oil I, and alkylate gasoline J were used. Their properties are as shown in Table 4. The catalytically modified medium oil H is obtained by distilling and separating a fraction rich in toluene from catalytically reformed gasoline. The catalytically modified heavy oil I is obtained by distilling and separating aromatics having 9 or more carbon atoms and less than 11 from catalytically modified gasoline.

  39.5% by volume of the desulfurized light fraction D2 obtained in Preparation 2 of the above-mentioned desulfurized light fraction, 3.5% by volume of desulfurized naphtha G as another gasoline base material, 0.05% by volume, 15.0% by volume of catalytically modified heavy oil I and 23.0% by volume of alkylate gasoline J are blended, and as an additive, a colorant (CL-53 manufactured by Shirad Chemical) is used. ) 2 mg / L, antioxidant (Sumitizer 4ML manufactured by Sumitomo Chemical Co., Ltd.) 20 mg / L, detergent dispersant (Keropur AP-95 manufactured by BSF) 100 mg / L were added, and unleaded gasoline composition K1 (Example 1) Was prepared. Further, an unleaded gasoline composition L1 (Comparative Example 1) was prepared in the same manner as the preparation of the unleaded gasoline composition K1 except that the catalytic cracking light fraction C2 was used instead of using the desulfurized light fraction D2.

  Similarly to the preparation of the unleaded gasoline composition K1, the desulfurized light fraction D3 is 40% by volume, the desulfurized naphtha G is 2% by volume, the catalytic reforming medium oil H is 11% by volume, and the catalytic reforming weight It contains 21% by volume of refined oil I and 26% by volume of alkylate gasoline J. As additives, 2mg / L of colorant (CL-53 made by Shirad Chemical), antioxidant (Sumilyzer 4ML made by Sumitomo Chemical) ) 20 mg / L, 100 mg / L of a detergent dispersant (Keropur AP-95 manufactured by BASF) was added to prepare an unleaded gasoline composition K2 (Example 2). Further, an unleaded gasoline composition L2 (Comparative Example 2) was prepared in the same manner as the preparation of the unleaded gasoline composition K2 except that the catalytic cracking light fraction C3 was used instead of using the desulfurized light fraction D3. .

  Table 5 shows the properties of the unleaded gasoline compositions K1, K2, L1, and L2 prepared as Examples and Comparative Examples, respectively. The olefin content in the boiling range of 25 to 100 ° C. in the total olefin content was 100% by volume for all of K1, K2, L1, and L2.

  From Table 5, the unleaded gasoline compositions provided by the present invention (K1 and K2) have almost no other changes compared to the unleaded gasoline compositions provided by the prior art (L1 and L2) It is clear that the sulfur content can be reduced to 1 ppm by mass or less, and the benzene content can be reduced to 0.3% by volume or less.

Claims (3)

  Research octane number is 96.0 or more, 50 volume% distillation temperature is 105 ° C. or less, olefin content is 10 volume% or more, total sulfur content is 1 mass ppm or less, and thiophene is 0.1 to 1.0 mass as sulfur content. The unleaded gasoline composition characterized by the ratio of the thiophene which occupies ppm and a total sulfur content being 65-100 mass% as a sulfur content.   The unleaded gasoline composition according to claim 1, wherein the olefin content in the boiling range of 25 to 100 ° C in the total olefin content is 90% by volume or more.   The unleaded gasoline composition according to claim 1 or 2, wherein the benzene content is 0.3 vol% or less.