JP4889095B2 - Eco-friendly gasoline composition and method for producing the same - Google Patents

Description

  The present invention relates to an environmentally friendly gasoline composition that takes into consideration the influence on the environment while ensuring sufficient operating characteristics, and a method for producing the same.

  Increasing the thermal efficiency of vehicle engines and reducing carbon dioxide emissions are being studied against the background of the Kyoto Protocol's carbon dioxide reduction. By increasing the gasoline research octane number (RON) as a measure, the compression ratio of the vehicle engine can be increased accordingly, and it is said that the energy conversion efficiency can be improved and the carbon dioxide emissions can be reduced. ing. On the other hand, the achievement rate of environmental standards such as photochemical oxidants is not always satisfactory, and demands for reducing fuel evaporative gas discharged from automobiles and purifying combustion exhaust gas tend to increase further. Therefore, further improvement in driving performance is desired, such as improving RON while suppressing environmental impact by reducing the lead vapor pressure (RVP) of summer gasoline and reducing sulfur content.

  JIS K 2202 “Automobile Gasoline” defines RON No.1 car gasoline with 96.0 or more and No.2 car gasoline with 89.0 or more. The former is high-performance premium gasoline and the latter is regular. Commercially available as gasoline. Conventionally, premium gasoline is a catalytically reformed gasoline base, a base with more than 100 RON such as methyl tertiary butyl ether (MTBE), an alkylate gasoline base, a light fraction base of catalytic cracked gasoline. It is manufactured by blending various gasoline base materials, mainly base materials having 93 or more RON. Regular gasoline is produced by adding desulfurized straight-run gasoline, aroma fraction, etc. with low RON, mainly on catalytic cracked gasoline base.

In general, cracked gasoline such as fluid catalytic cracked gasoline contains a relatively large amount of olefins and aroma (aromatics), and greatly contributes to improvement of RON. On the other hand, a fraction containing a large amount of paraffins such as desulfurized heavy naphtha (desulfurized straight-run heavy gasoline) is not preferred as a gasoline base material because it has a relatively low RON, and has not been used.
On the other hand, it is not preferable to use many aroma compounds and olefin compounds widely used as compounds having a high RON from the viewpoint of the environment. Specifically, it has been pointed out that the aroma compound has a problem of carcinogenicity and PRTR method, and when used as a fuel for automobiles, it changes into a particulate compound (PM) in the engine. Since the olefin content is photochemically unstable and a solid compound such as a sludge is precipitated, there is a drawback that it has a problem in storage stability.

  Furthermore, although an aroma compound has the advantage that RON is high, since it has a high boiling point and causes deterioration of operability during cold operation and deterioration of exhaust gas properties, it cannot be mixed in a gasoline base material too much. In addition, the olefin component tends to have a high RON for a relatively low molecular weight product, but tends to have a high RVP and cannot be used in a gasoline base material. From these results, it is considered that, in the future, there is a tendency that a distillation property is light, that is, a boiling point is relatively low and a RVP is low while securing a high RON.

  Taking the above situation into consideration and looking at the actual situation of gasoline production, catalytic cracking gasoline base materials produced by cracking heavy petroleum fractions are more economical to manufacture than other gasoline base materials. While there is an advantage that it can be done, it contains a lot of sulfur. As a result, most of the sulfur content in the gasoline produced as described above is derived from the catalytic cracked gasoline base material. The sulfur content contained in the catalytic cracking gasoline base material can be easily reduced using a known technique of hydrotreating in the presence of high-pressure hydrogen and a desulfurization catalyst. However, in that case, a large amount of catalytic cracking gasoline base material is contained, and the olefin component having high RON is hydrogenated to decrease the RON of the base material. There was a problem that it was difficult to obtain gasoline.

  On the other hand, paraffins and isoparaffins are effective as environmentally friendly clean fuels because they are less harmful to the environment than aroma compounds and olefin compounds. In particular, a technique for increasing RON, which is important as a gasoline base material, is known by increasing the proportion of isoparaffins obtained by skeletal isomerization of hydrocarbon oil under specific conditions (Non-Patent Document 1). ). Specifically, normal paraffin having a low RON is generally converted to isoparaffin having a high RON. However, such a skeletal isomerization reaction is not always satisfactory although a considerable effect can be obtained if an appropriate catalyst or process is used, and the isomerized oil produced generally has an increased RVP. In addition, it is difficult to finally obtain a satisfactory gasoline product even if the blend base is carefully selected and properly combined (Patent Document 1).

Moreover, there is an alkylation reaction as a process capable of selectively producing isoparaffin similarly to the isomerization reaction (Non-patent Document 2). The alkylation reaction is a reaction in which isobutane having 4 carbon atoms is mainly reacted with butene using an acid catalyst such as sulfuric acid or hydrofluoric acid to produce isoparaffin having 8 carbon atoms. In the past, it could not be produced in a large amount because of the use of an expensive compound having 4 carbon atoms. In addition, enormous energy is required to treat the acid used as the catalyst. Furthermore, although paraffins having 8 carbon atoms have an advantage of low RVP, the boiling point range is slightly high as 99 to 126 ° C., and a gasoline composition having favorable distillation properties, that is, an optimal compound that maintains good driving performance. It is difficult to say (Patent Document 2).
Japanese Patent Laid-Open No. 09-071788 JP 2000-073074 A The Japan Petroleum Institute, “Petroleum Refining Process 9. Isomerization”, pp. 235-245, Kodansha Scientific (1998) The Japan Petroleum Institute, “Petroleum Refining Process 8. Alkylation and Synthetic Fuel Process”, pages 209-233, Kodansha Scientific (1998)

  An environment-friendly gasoline composition having a sulfur content as low as 10 ppm by mass or less and ensuring sufficient practical performance and a method for producing the same have not yet been established. Under such circumstances, the present invention reduces the sulfur content to 10 ppm by mass or less, preferably 1 ppm by mass or less, and contains a specific gasoline component, so that an aroma component having a relatively large environmental load is contained. An object of the present invention is to provide an environment-friendly gasoline composition that has a density and distillation properties in an appropriate range without using a large amount of olefin, has a high calorific value, and has sufficient operation characteristics, and a method for producing the same. Is.

  As a result of diligent research to solve the above-mentioned problems, the present inventors have found a specific compound having a high RON and a calorific value, a low RVP, and a preferred range of distillation properties. By controlling, it discovered that the gasoline composition which reduced the sulfur content, aroma content, olefin content, etc. with a comparatively large environmental load, maintaining high RON, and arrived at this invention.

That is, the environment-friendly gasoline composition of the present invention has a 2,3-DMP content of 7 or more branching isoparaffins (Multi Branched C7 Iso-Paraffins: hereinafter referred to as MIP7). 0.55 or more (capacity ratio) and 0.25 or more (capacity ratio) with respect to the content of all C 7 paraffins (hereinafter referred to as WP7), and the research method octane number (RON) is 92 or more and 96 or less, the content of 2,3-dimethylpentane (2,3-DMP) is 1.80 vol% or more, the sulfur content is 10 massppm or less, and 50 vol% distillation temperature in distillation properties. Is a gasoline composition having an aromatic content of 40% by volume or less and an olefin content of 30% by volume or less.
Furthermore, environmentally friendly gasoline composition of the present invention, sulfur content of 1.0 mass ppm or less, the total calorific value 34.0kJ / mL or more, and more Reid vapor pressure (RVP) is less than 65kPa preferable.

  Further, the present invention is a method for producing the above-mentioned environment-friendly gasoline composition, wherein a catalytic reformed gasoline obtained by catalytic reforming of desulfurized straight-run heavy gasoline is extracted and aroma is removed. This is a method for producing the environmentally friendly gasoline composition using the obtained raffinate fraction containing a boiling point component of at least 80 to 110 ° C. as a gasoline base material.

The environment-friendly gasoline composition of the present invention has properties that cannot be considered in conventional unleaded gasoline compositions, that is, satisfactory RON and heat generation even when the sulfur content is reduced to 10 ppm by mass or less, and further to 1 ppm by mass or less. It became possible to have a quantity, distillation properties and RVP value. According to the present invention, an environmentally friendly gasoline composition having such special properties can be provided.
Furthermore, since the environmentally friendly gasoline composition obtained by the present invention has a very low sulfur content and a high content of saturated hydrocarbon compounds having a high degree of branching, as a fuel for gasoline engines, In addition, it has high energy efficiency as a fuel for fuel cells, and can be used as a common gasoline.

The inventor has focused on 7 carbon atoms and a multi-branched saturated hydrocarbon, particularly 2,3-dimethylpentane (2,3-DMP), having a relatively high RON of 91 and an RVP of 16 kPa. The boiling point is 90 ° C. and the density correlated with fuel consumption is 0.702 g / cm ³ , which is higher than other paraffin compounds having 7 carbon atoms, and has an ideal performance as a gasoline base material. 2,3-DMP includes other dimethylpentanes (2,2-dimethylpentane (2,2-DMP), 2,4-dimethylpentane (2,4-DMP), 3,3-dimethylpentane (3,2, Compared with 3-DMP)), as shown in Table 1, it is noted that RON is high, and the total heat generation amount per unit volume and the density related to the total heat generation amount are also large.

  Originally, a saturated hydrocarbon having 7 carbon atoms has a boiling point of 80 to 100 ° C. and an RVP of 10 to 25 kPa, and is a particularly desirable fraction for gasoline properties. However, RON is generally low overall, for example, normal hydrocarbon heptane, normal heptane has a RON of 0, and monobranched 2-methylhexane has a RON of 42. Substantially usable as a gasoline base material is multi-branched isoparaffin, that is, isoparaffin (MIP7) having two or more branches such as 2,3-DMP. That is, it is preferable as a gasoline property that the content of multi-branched isoparaffin (MIP7), especially 2,3-DMP, is particularly high relative to all paraffins (WP7) and isoparaffins (IP7) having 7 carbon atoms. However, in a general cracking reaction, it is difficult to obtain a multi-branched saturated hydrocarbon such as 2,3-DMP. Aroma is extracted and separated from catalytic reformed gasoline obtained by catalytic reforming reaction, and raffinate. It is effective to use a fraction containing a boiling point component of at least 80 to 100 ° C. obtained as (a raffinate fraction or simply referred to as raffinate).

[Gasoline composition]
The gasoline composition of the present invention has a sulfur content of 10.0 mass ppm or less. The smaller the amount of sulfur oxide in the exhaust gas, the better the environment. Therefore, it is preferably 5.0 mass ppm or less, more preferably 1.0 mass ppm or less. The sulfur content in gasoline becomes sulfur oxides in the exhaust gas, poisoning the nitrogen oxide removal catalyst and lowering the catalytic activity. The poisoned nitrogen oxide removing catalyst regenerates and recovers its activity in a reducing atmosphere. At this time, however, fuel is usually used to form a reducing atmosphere, which causes a deterioration in fuel consumption. Therefore, the fuel efficiency improves as the sulfur content in gasoline decreases.
Further, benzene is preferably 1% by volume or less, and more preferably 0.6% by volume or less in order to maintain good exhaust gas properties.

  Moreover, the gasoline composition of the present invention contains 1.8% by volume or more of 2,3-DMP as a hydrocarbon component. In order to ensure the effect of improving RON, it is more preferable to contain 2.0% by volume or more, and it is more preferable to contain 2.4% by volume or more. Further, the 2,3-DMP / MIP7 ratio (capacity) is preferably 0.55 or more, more preferably 0.65 or more, and still more preferably 0.80 or more, from the effect of improving RON. Further, the 2,3-DMP / WP7 ratio (capacity) is preferably 0.25 or more, more preferably 0.30 or more, and further preferably 0.35 or more, from the effect of improving RON. A gasoline composition having a 2,3-DMP content of 1.80% by volume or more, or a 2,3-DMP / MIP7 ratio of 0.55 or more, and a 2,3-DMP / WP7 ratio of 0.25 The above gasoline composition has suitable distillation properties and RVP, and exhibits high RON.

  2,3-DMP may be introduced into the gasoline composition in any form, but is obtained when the aroma is extracted and separated from the catalytic reforming reaction product oil (catalytic reforming gasoline). Since a large amount is contained in the catalytically modified raffinate, the catalytically modified raffinate may be blended in such a ratio that 2,3-DMP is contained in the gasoline composition. As other methods, it cannot be said that it is very economical at present, but a method using a single 2,3-DMP, combining one or more olefins having about 3 to 4 carbon atoms and isoparaffins having about the same carbon number. Polymerize appropriately and, if necessary, hydrogenate unsaturated bonds to convert them to stable saturated bonds, or isomerize paraffins centered on carbon number 7 to carbonize with a high 2,3-DMP content Examples thereof include a method for obtaining hydrogen oil, and these may be used. For example, when a fraction mainly composed of propylene and butylene is subjected to an alkylation reaction with a solid phosphoric acid catalyst and then an olefin content is hydrogenated with a nickel-molybdenum catalyst, a hydrocarbon having a high 2,3-DMP content. Since oil can be obtained, this may be used.

  Further, normal paraffins as other paraffin compounds are preferably as low as RON is low, and are preferably 12.0% by volume or less, and more preferably 8.0% by volume or less. The total number of paraffins having 7 carbon atoms (WP7) is preferably 4.0% by volume or more, more preferably 5.0% by volume or more, and the content of isoparaffins having 7 carbons (IP7) is 3.5% by volume or more. More preferably, it is 4.5% by volume or more, and the content of multi-branched isoparaffin (MIP7) having 2 or more carbon atoms and 7 branches is preferably 1.0% by volume or more, particularly 2.0% by volume or more. Is preferred.

Furthermore, the aroma content of the gasoline composition of the present invention is 40% by volume or less. Preferably it contains in the range of 10-40 volume%. From the standpoint of maintaining RON and fuel consumption, it is more preferably 15% by volume or more, and further preferably 20% by volume or more. On the other hand, from the viewpoint of maintaining exhaust gas properties and low-temperature drivability, the amount of aroma is preferably as small as possible, more preferably 38% by volume or less, and particularly preferably 35% by volume or less.
The olefin content is 30% by volume or less. Preferably it contains in the range of 10-30 volume%. From RON maintenance and fuel consumption, it is more preferably 11% by volume or more, and further 12% by volume or more. On the other hand, from the viewpoint of light stability and storage stability, the olefin content is preferably as small as possible, more preferably 25% by volume, particularly preferably 20% by volume or less.
The gasoline composition of the present invention has a high RON in the past by finely adjusting the blending amount of oxygen-containing gasoline base materials and various gasoline base materials in consideration of the content of specific components such as 2,3-DMP. The RON can be ensured even if the aroma content that has been frequently used for obtaining is reduced as much as possible.

  Furthermore, the environment-friendly gasoline composition of the present invention may contain 0 to 2.7% by mass of an oxygen-containing compound as oxygen. More preferably, the content is 0.1 to 2.5% by mass. As the oxygen-containing compound, a biomass-derived compound is preferably used from the viewpoint of dealing with environmental problems of exhaust gas. In the gasoline composition, oxygen is introduced in the form of an oxygen-containing gasoline base material, which is a hydrocarbon compound containing oxygen, or in the form of an additive containing a compound containing another element. However, since the additive content is usually very small, it can be considered that substantially all oxygen content is brought into the oxygenated gasoline base.

  The environmentally friendly gasoline composition of the present invention has a RON of 92 or more and 96 or less, preferably 93 or more, more preferably 95 or more. Further, the total calorific value is preferably 34.0 kJ / mL or more. From the viewpoint of fuel consumption, it is more preferably 34.2 kJ / mL or more.

  This gasoline composition has a distillation property with a 50% distillation temperature of 88 to 100 ° C., preferably 89 ° C. or more, more preferably 90 ° C. or more from the viewpoint of fuel consumption, and 97 ° C. from low temperature drivability. The following is preferable, more preferably 96 ° C or lower. The 90% distillation temperature is preferably 110 to 160 ° C., more preferably 115 ° C. or higher, more preferably 120 ° C. or higher, from the viewpoint of fuel efficiency and maintaining the cleanliness of the direct injection engine, and suppressing an increase in evaporated gas due to an increase in light components. In particular, 125 ° C. or higher is preferable. On the other hand, from a low temperature drivability, 155 ° C. or lower is more preferable, 152 ° C. or lower, particularly 150 ° C. or lower is preferable.

  The environment-friendly gasoline composition according to the present invention preferably has a Reed Vapor Pressure (RVP) at 37.8 ° C. of at least 44 to 93 kPa, and preferably 65 kPa or less. When the RVP is high, problems such as an increase in evaporation loss, a concern about vapor lock, and an increase in danger are likely to occur. On the other hand, when the RVP is low, the low-temperature drivability is impaired.

[Gasoline base material]
The environment-friendly gasoline composition of the present invention can be prepared by carefully selecting conventional so-called gasoline base materials so as to satisfy the above-mentioned properties and compositions, and combining them carefully. Examples of gasoline base materials that can be suitably used in the present invention include catalytic reformed gasoline (RF), C7 aromatic fraction (AC7) and C9 aromatic fraction (AC9) derived from catalytic reformed gasoline, and catalytic reforming. There may be mentioned gasoline substrates such as raffinate fraction (RAF), catalytic cracking gasoline (FCCG), desulfurized straight-run light gasoline (DS-LG), alkylate gasoline (ALKG), oxygenated gasoline substrate and the like.

[Contact reforming gasoline (RF)]
The catalytic reformed gasoline that is the raw material of the environment-friendly gasoline composition of the present invention is a desulfurized straight-run heavy gasoline, for example, a reforming catalyst in which platinum or other noble metal is supported on an alumina carrier, a reaction temperature of 470 to 550 ° C., It is produced by contact under reaction conditions of reaction pressure of 0.3 to 1.1 MPa, liquid hourly space velocity (LHSV) of 0.5 to 2.0 h ⁻¹ , and H ₂ / oil ratio of 0.1 to 10.0 mol / mol. The The catalytic reforming reaction consists of (1) conversion of naphthenic hydrocarbons to aromatic hydrocarbons (dehydrogenation), (2) conversion of paraffinic hydrocarbons to aromatic hydrocarbons by cyclodehydrogenation, (3) It is said that there are four types of reactions: isomerization of naphthenic and paraffinic hydrocarbons, and (4) hydrocracking. Low-octane desulfurized straight-run heavy gasoline is a catalytic reforming of high octane number such as RON 95-100. It is reformed to gasoline. In the production of higher-octane catalytic reformed gasoline, since the catalyst deteriorates quickly, a fluidized bed type capable of continuous regeneration is employed. Industrial processes for naphtha catalytic reforming include platform formers, reni formers, power formers, magna formers, and foody formers.

[Catalytically modified raffinate fraction (RAF)]
The process for producing the catalytic reforming extract fraction and the catalytic reforming raffinate fraction, which are raw materials for the environment-friendly gasoline composition of the present invention, does not particularly limit the extraction apparatus and the operating conditions, and any known arbitrary A manufacturing process can be adopted. For example, a catalytically reformed gasoline that is a feedstock is mixed with a solvent that selectively extracts aroma, for example, sulfolane (tetrahydrothiophene dioxide). Extraction conditions include an extract fraction in which the aroma compound is selectively extracted and separated by sulfolane by treating the temperature at 20 to 100 ° C. and the pressure from normal pressure to 1.0 MPa, and a paraffin type that is not extracted into the solvent. The hydrocarbon is separated into a concentrated raffinate fraction. The raffinate fraction containing a boiling point component of at least 80 to 100 ° C. obtained by this extraction treatment from the catalytic reformed gasoline obtained from the catalytic reformer contains a relatively large amount of 2,3-DMP. It can be particularly preferably used as a gasoline base material for producing the environment-friendly gasoline composition of the present invention. In this case, in order to obtain a raffinate fraction containing a boiling point component of at least 80 to 100 ° C., the obtained catalytic reformed gasoline may be subjected to an extraction treatment. In addition, the extraction treatment is carried out after fractionating the catalytic reformed gasoline. Alternatively, the raffinate fraction from which catalytic reformed gasoline is extracted may be fractionated.

  Furthermore, the aroma content and sulfolane contained in the extract fraction are easily separated by a distillation operation, and the separated sulfolane is reused as an extraction solvent.

[Catalytic cracking gasoline (FCCG)]
The process for producing the catalytic cracking gasoline does not particularly limit the catalytic cracking apparatus, the feed oil, and the operating conditions, and any known one can be adopted. Catalytic cracking equipment uses a catalyst such as amorphous silica alumina, zeolite, etc., and high-boiling fractions higher than kerosene, such as petroleum fractions from light oil to vacuum gas oil, and degassed oil obtained from heavy oil indirect desulfurization equipment Alternatively, it is an apparatus for obtaining catalytic cracking oil (such as catalytic cracking gasoline) having a high octane number by catalytic cracking of directly desorbed heavy oil, atmospheric residue oil obtained from heavy oil direct desulfurization equipment. In catalytic cracking, it is necessary to regenerate the catalyst by burning and removing coke adhering to the catalyst. Currently, fluidized-bed catalytic cracking (FCC) is employed exclusively. For example, UOP catalytic cracking, flexi There are fluid catalytic cracking method such as cracking method, ultra ortho flow method, texaco fluid catalytic cracking method, residual oil fluid catalytic cracking method such as RCC method, HOC method, etc. (Japan Petroleum Institute, “Petroleum Refining Process”, p125 156, Kodansha Scientific (1998)). This catalytic cracking gasoline is about RON 90-93.

[Desulfurization catalytic cracking gasoline (DS-FCCG)]
Catalytic cracking gasoline (FCCG) uses a raw material with a high sulfur content, so it has a higher sulfur content than catalytic reforming gasoline and light desulfurization straight gasoline, which will be described later. Desulfurization catalytic cracking gasoline (DS-FCCG) having a content reduced to 1 mass ppm or less can be obtained. In the desulfurization of FCCG, the desulfurization treatment method is not particularly limited, but a collecting / removing sulfur method capable of performing the desulfurization treatment without lowering the RON is preferable. It is preferable to carry out catalytic cracking gasoline through a fixed bed desulfurization tower filled with a desulfurizing agent because separation of the desulfurizing agent and the resulting desulfurized cracked gasoline can be easily performed. The temperature for the desulfurization treatment can be selected from the range of 0 to 400 ° C, and preferably from the range of 20 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 catalytic cracking gasoline into contact with each other in a fixed bed flow system, the LHSV is preferably selected from the range of 0.01 to 10,000 h ⁻¹ .

[Desulfurized straight-run light gasoline (DS-LG)]
The process for producing desulfurized straight-run light gasoline does not particularly limit the feedstock, distillation apparatus, and operating conditions, and any known one can be employed. For example, a naphtha fraction obtained from a crude oil distillation step is desulfurized using a catalyst containing nickel, cobalt, molybdenum and the like in the presence of hydrogen. By setting the reaction conditions to a reaction temperature of 250 to 400 ° C., a reaction pressure of 1.0 to 8.0 MPa, an LHSV of 0.5 to 10.0 h ⁻¹ , and an H ₂ / oil ratio of 0.1 to 20.0 mol / mol, And sulfides are hydrodesulfurized. Among the above reaction conditions, particularly preferable reaction conditions are, for example, a reaction temperature of 280 to 320 ° C., a reaction pressure of 3.0 to 4.0 MPa, an LHSV of 2.0 to 4.0 h ⁻¹ , and an H ₂ / oil ratio of 1.0. -0.0 mol / mol.

  The desulfurized straight-run light gasoline is a fraction containing a boiling point component of at least 45 to 60 ° C, preferably 35 to 70 ° C. The preferred distillation temperature is 10 vol% distillation temperature of 35 to 45 ° C, 90 vol% distillation temperature of 60 to 68 ° C, and 95 vol% distillation temperature of 70 to 75 ° C. The aroma content of the desulfurized straight run light gasoline is preferably 0 to 1.0% by volume.

[Other gasoline base materials]
In addition to the above-mentioned gasoline bases such as RAF, DS-FCCG, DS-LG, etc., the environmentally friendly gasoline composition of the present invention is blended with an appropriate ratio of gasoline bases that have been used in conventional gasoline production. Can be manufactured by. As such a gasoline base material, specifically, contact of light fraction obtained by distilling alkylate gasoline (ALKG) obtained by alkylating butylene fraction and isobutane fraction and catalytic cracking gasoline (FCCG). Decomposed light gasoline (FL), aroma compound fraction (AC7, AC9, etc.) that is aroma-rich with a specific carbon number obtained by distillation of catalytically reformed gasoline, and gasoline by-produced from various refining processes of crude oil Examples of the fraction include isolated butane and pentane, aroma compounds such as so-called BTX, and oxygen-containing gasoline base materials.

[Oxygen-containing gasoline base material]
As the oxygen-containing gasoline base material, for example, alcohols having 2 to 5 carbon atoms and ethers having 4 to 8 carbon atoms can be suitably used. Specifically, ethanol, normal propyl alcohol, isopropyl alcohol, normal butyl alcohol, secondary butyl alcohol, butyl alcohol such as tertiary butyl alcohol, alcohols such as amyl alcohol, and ethers that are derivatives from alcohols And esters such as ethyl isopropyl ether, methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), ethyl secondary butyl ether (ESBE), diisopropyl ether, tertiary amyl ethyl ether (TAEE), ethyl acetate, propion Examples include ethyl acid.

  As described above, these oxygen-containing compounds can be added to the environment-friendly gasoline composition of the present invention in an amount of 0 to 2.7% by mass as oxygen, and more preferably 0.1 to 2.5% by mass. If the amount is too small, the effect of improving RON is small. If the amount is too large, impurities such as moisture are accompanied, causing troubles such as corrosion of piping and sealing materials. For example, if it is contained in a large amount in the fuel, water may be concentrated in the automobile fuel tank and accumulate, which may have an adverse effect. Furthermore, the air / fuel ratio of the existing engine will deviate from the optimum value, resulting in excess oxygen. There is a drawback in that the amount of nitrogen oxides (NOx) in the exhaust gas increases because it makes a difference. Further, since oxygen-containing compounds generally have a lower total calorific value than other gasoline base materials and may reduce fuel consumption, it is not preferable to use too much.

〔Additive〕
As a preferred embodiment of the environment-friendly gasoline composition of the present invention, a known fuel additive can be blended as necessary. Although these compounding quantities can be chosen suitably, it is usually preferable to set it as 0.1 volume% or less as a total amount of an additive. Examples of additives that can be used in the environment-friendly gasoline composition of the present invention include amine-based, phenol-based, aminophenol-based antioxidants, Schiff-type compounds, metal deactivators such as thioamide-type compounds, Surface ignition inhibitors such as organic phosphorus compounds, detergents and dispersants such as succinimides, polyalkylamines and polyetheramines, anti-icing agents such as polyhydric alcohols and ethers, alkali metal salts and alkaline earths of organic acids Auxiliary agents such as metal salts, higher alcohol sulfates, anionic surfactants, cationic surfactants, amphoteric surfactants, rust inhibitors such as alkenyl succinates, quinizarin, coumarins, etc. Examples thereof include colorants such as discriminating agents and azo dyes.

  Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to these examples.

  In order to evaluate the gasoline compositions of Examples and Comparative Examples, the gasoline base material used for the preparation was procured by the method shown below. Table 2 shows the properties of each gasoline base material procured. Moreover, the gasoline composition of Examples 1-6 and Comparative Examples 1-6 was prepared by mixing each gasoline base material in the blending ratio (volume%) shown in the upper part of Table 3. The properties of the gasoline compositions of Examples and Comparative Examples were measured, and the results are also shown in Table 3.

Butane fraction (C4)
This is a so-called butane fraction. It contains 95% or more of hydrocarbons having 4 carbon atoms by distillation separation of desulfurized liquefied petroleum gas such as desulfurized light naphtha and light fraction of catalytic reformed gasoline, and 73% by volume of normal butane. A fraction containing was obtained.
Desulfurized straight run light gasoline (DS-LG)
The naphtha fraction of Middle Eastern crude oil was hydrodesulfurized and then subjected to distillation treatment to separate it into desulfurized straight-run light gasoline and desulfurized straight-run heavy gasoline.

Alkylate gasoline (ALKG)
A fraction containing butylene as a main component and a fraction containing isobutane as a main component were reacted with a sulfuric acid catalyst or a solid phosphoric acid catalyst to obtain a hydrocarbon having a high isoparaffin content.

Catalytic reforming gasoline (RF)
Desulfurized straight-run heavy gasoline is reacted with a catalytic reforming catalyst in a hydrogen stream at a reaction temperature of 520 ° C., a reaction pressure of 0.34 MPa, an LHSV of 1.2 h ⁻¹ , and an H ₂ / oil ratio of 2.0 mol / mol. Of high catalytic reforming gasoline.

Catalytically modified raffinate fraction (RAF)
An equivalent amount (by weight) of sulfolane as an extraction solvent was mixed with the catalytic reformed gasoline. The extraction temperature is 60 ° C., the normal pressure, the contact time is 10 minutes, and the mixture is stirred and mixed to separate the extract from which the aroma compound has been selectively extracted and the residue from which the aroma compound has been removed (raffinate). The The extract was separated by distillation to obtain an aroma compound extract and an extraction solvent sulfolane. On the other hand, the catalytically modified raffinate fraction (RAF) was obtained by washing the extraction residue with water to remove sulfolane.

Aroma compound fraction (AC7, AC9)
Aroma-rich fraction (AC7) containing 95% by volume of hydrocarbons having 7 carbon atoms and aroma containing 95% by volume or more of hydrocarbons having 9 carbon atoms by distillation separation of the catalytic reformed gasoline (RF) A rich fraction (AC9) was obtained.

Catalytic cracking gasoline (FCCG)
Hydrocarbons with a high olefin content were obtained by hydrotreating a vacuum gas oil fraction of Middle Eastern crude oil as a main feedstock using a fluidized bed reactor with a solid catalyst.

Desulfurization cracking gasoline (DS-FCCG)
Hydrocarbon having a low sulfur content was obtained by collecting and removing the FCCG. After sulfiding a catalyst carrying 20% by mass of nickel on alumina, FCCG was passed through under conditions of reaction temperature 250 ° C., reaction pressure and normal pressure, LHSV4h ⁻¹ , H ₂ / oil ratio 340 NL / L. Diene reduction treatment was performed. Thereafter, reduction treatment of copper zinc aluminum composite oxide (copper content 35% by mass, zinc content 35% by mass, aluminum content 5% by mass) which is a desulfurization agent having a sorption function prepared by a coprecipitation method. The diene-reduced catalytically cracked gasoline was passed through under conditions of a reaction temperature of 100 ° C., a reaction pressure of normal pressure, an LHSV of 2.0 h ⁻¹ , an H ₂ / oil ratio of 0.06 NL / L, and desulfurized. Cracked gasoline (DS-FCCG) was obtained.

  Commercially available fermented ethanol (99 degrees first grade, manufactured by Nippon Alcohol Sales Co., Ltd.) was used.

Ethyl tertiary butyl ether (ETBE)
Ethanol and isobutylene were reacted using an ion exchange resin catalyst (Amberlyst-15), and then purified by distillation to obtain ETBE having a purity of 95% or more.

The density was measured by the vibration type density test method of JIS K 2249, the Reed vapor pressure (RVP) was measured by the Reed method vapor pressure test method of JIS K 2258, and the distillation property was measured by the atmospheric pressure distillation test method of JIS K 2254. The sulfur content was measured by the ultraviolet fluorescence method of JIS K2541-6. The silver plate corrosion is measured according to “14. Silver plate” of JIS K2276 (Petroleum product-aviation fuel oil test method) instead of the copper plate in the cylinder method (jet fuel) of JIS K2513 (Petroleum product-copper plate corrosion test method: corresponding ASTM D130). The silver plate used in the “corrosion test method” was evaluated. The component composition of hydrocarbon is JIS K 2536 gas chromatographic all component test method and fluorescent indicator adsorption method for determination of aroma, olefin content and saturation content by type. RON uses PIONA manufactured by Hured Packard. Measured by gas chromatography. The total calorific value was measured by the calorific value estimation method of JIS K 2279. Note that the total calorific value (Hg: higher calorific value) and the true calorific value (Hn: lower calorific value) are converted by the following equation according to the method described in Appendix 2 of JIS K2276.
Hn = Hg-6 (9h + W)
Here, Hn represents a true calorific value (cal / g), Hg represents a total calorific value (cal / g), h represents a hydrogen content (mass%), and W represents moisture (mass%).

  From Table 3, the environmentally friendly gasolines of Examples 1 and 2 are compared with the conventional gasolines of Comparative Examples 1 and 2, instead of desulfurized straight-run light gasoline (DS-LG), the catalytically modified raffinate fraction. By using (RAF), it can be seen that the 2,3-DMP ratio for the multi-branched isoparaffin having 7 carbon atoms (MIP7) and the 2,3-DMP ratio for the paraffin having 7 carbon atoms (WP7) are high. As a result, the environmentally friendly gasolines of Examples 1 and 2 are suitable as the comparative examples 1 and 2, even though the distillation properties and sulfur concentration are the same, RON and calorific value are high and RVP is low and appropriate. It can be seen that the gasoline has a practical performance and reduces the environmental load.

As in the case of Example 1 described above, the environmentally friendly gasolines of Examples 3 and 4 were compared with the conventional gasolines of Comparative Examples 3 and 4 as well as the 2,3-DMP ratio for MIP7 and 2 for WP7. It can be seen that the 3-DMP ratio is high. In addition, the environment-friendly gasoline (Examples 3 and 4) of the present invention has a high RON, a high calorific value, and a low RVP. Therefore, it can be seen that the environmentally friendly gasolines of Examples 3 and 4 are also gasolines that have an excellent practical performance as in Examples 1 and 2 and reduce the environmental load.
As in the case of Examples 1 to 4, the environmentally friendly gasolines of Examples 5 and 6 were compared with the conventional gasolines of Comparative Examples 5 and 6, and the 2,3-DMP ratio relative to MIP7, and WP7. It can be seen that the 2,3-DMP ratio is high. In addition, the environment-friendly gasoline (Examples 5 and 6) of the present invention has a high RON, a high calorific value, and a low RVP. Therefore, it can be seen that the environment-friendly gasolines of Examples 5 and 6 are also gasolines that have an excellent practical performance as in Examples 1 and 2 and reduce the environmental load.

Claims (5)

The content of 2,3-dimethylpentane is 0.55 or more (volume ratio) with respect to the content of isoparaffin having 7 or more carbon atoms and 2 or more branches, and the content of all paraffins having 7 carbon atoms. 0.25 or more (volume ratio) with respect to the content , the research octane number is 92 or more and 96 or less, the content of 2,3-dimethylpentane is 1.80 vol% or more, the sulfur content is 10 mass ppm or less, distillation An environment-friendly gasoline composition having a 50 vol% distillation temperature of 88 to 100 ° C, aroma content of 40 vol% or less, and an olefin content of 30 vol% or less. The gasoline composition according to claim 1 , wherein the sulfur content is 1.0 mass ppm or less. The gasoline composition according to claim 1 or 2 , wherein the total calorific value is 34.0 kJ / mL or more. The gasoline composition according to any one of claims 1 to 3 , wherein the lead vapor pressure is 65 kPa or less. Extraction treatment of catalytically reformed gasoline obtained by catalytic reforming of desulfurized straight-run heavy gasoline and removal of aroma, and using a raffinate fraction containing a boiling point component of at least 80 to 110 ° C. as a gasoline base material The method for producing an environmentally friendly gasoline composition according to any one of claims 1 to 4 , wherein the method is used.