JP2007246766A - Unleaded gasoline - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an unleaded gasoline excellent in startability and operability of automobiles in consideration of the air environment. <P>SOLUTION: The unleaded gasoline contains 1-15 vol% of ethanol (EtOH) and has (1) a research octane number of at least 89 and less than 97, (2) a motor octane number of at least 79 and less than 87, (3) a Reid vapor pressure of 45-93 kPa, (4) a 50% distillation temperature of 75-110°C, (5) a 70°C distillation amount of 18-40 vol%, (6) a 130°C distillation amount of 68-92 vol%, (7) an aromatics content of at most 40 vol%, (8) an olefin content of at most 30 vol%, (9) a benzene content of at most 1 vol%, and (10) a sulfur content of at most 10 mass ppm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ethanol blended gasoline, and more particularly to an unleaded gasoline having an identified distillation property and an identified component composition, environmentally friendly as an automobile fuel, and excellent in startability and drivability.

In recent years, fuel oils for gasoline engines have been demanded that have a high octane number and excellent driving performance as well as excellent environmental performance.
In general, as a high-octane gasoline, a high octane number base material having a heavy and high aromatic content and a specific distillation property and component composition are known (see, for example, Patent Document 1).

In the case of this high-octane gasoline, the octane number of the high-boiling fraction is improved because a high-octane base material with a heavy aromatic content is added. However, the gasoline becomes heavier and produces deposits in the engine. In particular, there are concerns about deposits on the intake valves and influence on drivability.
In order to improve the heaviness of gasoline and the adhesion of deposits to the intake valve, it is considered important to add a light and high octane base material.

In addition, gasoline that contains methyl tertiary butyl ether (MTBE), which is an oxygen-containing compound, is known for reducing carbon monoxide (CO), total hydrocarbons (THC), and the like in automobile exhaust gases (for example, Patent Document 2).
However, there is concern about the environmental impact of MTBE, and now production and sales of gasoline containing MTBE are restrained in Japan. Since MTBE is a base material having a high octane number, when the mixing of MTBE is stopped, a high octane number base material is required instead. Among them, oxygen-containing organic compounds other than MTBE, which compensate for the decrease in octane number of gasoline and are considered to have a low environmental load, are attracting attention as new gasoline base materials. Among these, ethanol has a high octane number, does not contain aromatics and olefins, and has an advantage that it can be regarded as a renewable fuel when considered as biomass (see, for example, Non-Patent Document 1).
As a blend of ethanol with gasoline, it contains 1 to 10% by volume of ethanol and 90 to 99% by volume of base gasoline, and based on the total amount of base gasoline, normal paraffin hydrocarbons, isoparaffin hydrocarbons, There exists what represented the relationship between an olefinic hydrocarbon and an aromatic hydrocarbon in the type | formula (for example, refer patent document 3 and patent document 4). However, these inventions were born from the problem that the motor octane number of ethanol blended gasoline could not be accurately predicted because the apparent motor octane number of blended ethanol differs depending on the base gasoline blended. It is necessary to improve the startability and acceleration of automobiles using gasoline.

Japanese Unexamined Patent Publication No. 7-207286 Japanese Patent Publication No. 5-53197 JP 2005-29760 JP 2005-29761 A "Automotive Fuels Reference Book" Second Edition, Owen, K.M. and Coley, T .; , P268 (1995)

  SUMMARY OF THE INVENTION An object of the present invention is to provide an ethanol blended gasoline that is excellent in startability and acceleration of an automobile in consideration of the atmospheric environment.

As a result of intensive studies to achieve the above object, the present inventors have selected ethanol (EtOH), which is a light high octane base, and selected a specific amount of EtOH, a specific component composition, and a specific distillation property. It has been found that gasoline having various performances can be obtained by constituting gasoline so as to have the above, and the above object can be achieved, and the present invention has been completed.
That is, the present invention provides an unleaded gasoline characterized by containing 1 to 15% by volume of ethanol (EtOH) and satisfying the following properties.
(1) Research method octane number (RON) is 89 or more and less than 97 (2) Motor method octane number (MON) is 79 or more and less than 87 (3) Reed vapor pressure (RVP) is 45 to 93kPa
(4) 50% distillation temperature (T50) is 75-110 ° C
(5) Distillation at 70 ° C (E70) is 18-40% by volume
(6) Distillation amount at 130 ° C. (E130) is 68 to 92% by volume
(7) Aromatic content 40% or less (8) Olefin content 30% or less (9) Benzene content 1% or less (10) Sulfur content 10 mass ppm or less

  The unleaded gasoline of the present invention contains a specific amount of ethanol and is used in a gasoline engine for automobiles. It is excellent in air environment conservation, startability and drivability, and maintains practical performance while maintaining atmospheric performance. The environment will be preserved.

Hereinafter, the contents of the present invention will be described in more detail.
Ethanol (EtOH) used in the unleaded gasoline of the present invention has a purity of 92.0% by volume or more, preferably 95.0% by volume or more, more preferably 99.5% by volume or more.
The method for producing ethanol is not particularly limited, and all generally produced ethanol can be used.
The content of ethanol is in the range of 1% by volume to 15% by volume, and preferably 3% by volume to 15% by volume with respect to the total amount of ethanol-blended gasoline. If it is 1% by volume or more, the advantage of improving the octane number by blending with ethanol can be obtained, and if it is 15% by volume or less, the evaporation characteristics do not change significantly due to the azeotropic phenomenon with other gasoline base materials. The proper drivability can be secured.

  (A) Research method octane number (RON) of the unleaded gasoline of the present invention is 89 or more and less than 97, preferably 89 to 95, and (b) Motor method octane number (MON) is 79 or more and less than 87, preferably 79 to 85. If RON is 89 or more, it is possible to maintain high driving performance, and if MON is 79 or more, it is possible to prevent a decrease in anti-knock property at high speed. Note that RON and MON are values measured in accordance with JIS K 2280.

  The lead vapor pressure (RVP) of the unleaded gasoline of the present invention is 45 to 93 kPa, preferably 50 to 90 kPa. By setting the RVP to 93 kPa or less, the amount of evaporative gas can be reduced, and by setting it to 45 kPa or more, it is possible to prevent the low temperature startability and warming performance from being deteriorated. This Reid vapor pressure (RVP) is a value measured according to JIS K 2258.

  The distillation properties of the unleaded gasoline of the present invention are as follows: (a) 50% distillation temperature (T50) is 75 to 110 ° C, preferably 75 to 105 ° C, (b) 70 ° C distillation amount (E70) is 18 to 40% by volume, preferably 20 to 40% by volume, (c) the 130 ° C. distillate (E130) is 68 to 92% by volume, preferably 70 to 90% by volume, and T50, E70 and E130 are in the above range. If it is inside, the case where a malfunction arises in startability, drivability, and acceleration can be prevented. These distillation properties are values measured in accordance with JIS K 2254.

  The aromatic content of the unleaded gasoline of the present invention is 40% by volume or less, preferably 5 to 35% by volume. If the aromatic content is within 40% by volume, an increase in harmful components in the exhaust gas can be prevented. The aromatic content is a value measured in accordance with the Petroleum Institute Method JPI-5S-33-90 (gas chromatographic method).

The olefin content of the unleaded gasoline of the present invention is 30% by volume or less, preferably 5 to 27% by volume. When the olefin content is within 30% by volume, it is possible to prevent a decrease in oxidation stability. The olefin content is a value measured in accordance with the Petroleum Institute method JPI-5S-33-90 (gas chromatographic method).

The benzene content of the unleaded gasoline of the present invention is 1% by volume or less, preferably 0.8% by volume or less. If the benzene content is within 1% by volume, there is a possibility that the increase in benzene concentration in the atmosphere can be prevented and environmental pollution can be reduced. The benzene content is a value measured according to the Petroleum Institute method JPI-5S-33-90 (gas chromatographic method).

  The sulfur content of the unleaded gasoline of the present invention is 10 mass ppm or less, preferably 8 mass ppm or less. If the sulfur content is within 10 ppm by mass, there is a possibility that the exhaust gas purification catalyst capacity can be prevented from being lowered and the concentration of NOx, CO and THC in the exhaust gas can be prevented from increasing. The sulfur content is a value measured according to JIS K 2541.

  In the unleaded gasoline of the present invention, the ratio of aromatics having 9 or more carbon atoms to the total aromatics (hereinafter also referred to as (C9 + A) / TA) is 0.80 or less, preferably 0.10 to 0.80. . It is preferable that the ratio of the aromatic component having 9 or more carbon atoms and the total aromatic component is 0.80 or less because it is possible to prevent the smoldering property of the plug from being lowered. The aromatic content is a value measured in accordance with the Petroleum Institute Method JPI-5S-33-90 (gas chromatographic method).

The base material other than EtOH for producing unleaded gasoline having the above properties is not particularly limited, and for example, the following various fractions can be used as the base material.
(B) Hydrogen stream by contact reforming method (Platforming method, Magnaforming method, Aromaizing method, Reforming method, Food reforming method, Ultraforming method, Powerforming method, etc.) for heavy straight-run naphtha, etc. In which the benzene fraction is removed by distillation from a reformed gasoline obtained by contact treatment with a catalyst (for example, platinum, rhodium and chlorine supported on an alumina carrier) at high temperature and pressure. Quality gasoline.
(B) The reformed gasoline obtained by contact treatment by the above catalytic reforming method is separated into light fraction, benzene fraction, and heavy fraction by distillation. Gasoline) and heavy fractions (debenzene heavy catalytic reforming gasoline).
(C) Petroleum fraction ranging from kerosene / light oil to atmospheric residual oil, preferably heavy gas oil or vacuum gas oil, is conventionally known catalytic cracking method, especially fluid catalytic cracking method (UOP method, shell two-stage type) Decomposition with a solid acid catalyst (eg, silica / alumina blended with zeolite) by the method, flexi cracking method, ultra ortho flow method, texaco method, Gulf method, ultra cat cracking method, RCC method, HOC method, etc. Catalytic cracking gasoline.
(D) Desulfurized light naphtha, which is a light fraction obtained by distilling a straight-run naphtha obtained by desulfurizing straight-run naphtha obtained by atmospheric distillation of crude oil into a light fraction and a heavy fraction by distillation.
(E) An alkylate obtained by reacting isobutane with a lower olefin (butene, propylene, etc.) in the presence of an acid catalyst (sulfuric acid, hydrogen fluoride, aluminum chloride, etc.).
(F) C4 fraction mainly composed of butane and butenes obtained by distillation during the atmospheric distillation of crude oil or crude oil, during the production of reformed gasoline, or during the production of cracked gasoline.
(G) Isomerate obtained by isomerization of straight-chain lower paraffin hydrocarbons, isopentane obtained by precision distillation of isomerate, toluene, xylene obtained from catalytically reformed gasoline, or aroma having 9 or more carbon atoms Ingredients mainly composed of tribes.

  The unleaded gasoline of the present invention is produced by appropriately selecting the blending amount of the above various fractions according to the properties of the various fractions so as to satisfy the above properties and appropriately blending with EtOH. be able to. For example, (I) EtOH 1-15% by volume, (II) RON 93 or more, MON 83 or more, RVP 30kPa or more, boiling point range 28-200 ° C debenzene catalytic reforming gasoline 2-20 capacity %, Or (III) RON is 78 or more, MON is 70 or more, RVP is 85 kPa or more, debenzene light catalytic reforming gasoline having a boiling point range of 26-80 ° C, 2-10% by volume, RON is 101 or more, MON 89 or more, RVP of 3 kPa or more, 2 to 15% by volume of debenzene heavy catalytic reformed gasoline having a boiling range of 90 to 200 ° C, and (IV) RON of 88 or more, MON of 77 or more, RVP of 40 kPa or more, 30 to 70% by volume of catalytic cracking gasoline with a boiling range of 30 to 210 ° C, 5 to 30% by volume of desulfurized light naphtha with RON of 65 or more, MON of 62 or more, RVP of 75kPa or more, and boiling range of 25 to 100 ° C The unleaded gasoline of the present invention can be produced by blending so as to satisfy the above properties. In addition, the composition of each substrate as described above has (V) RON of 93 or more, MON of 90 or more, RVP of 40 kPa or more, boiling range of 30 to 210 ° C., and C8 fraction of 65% by volume or more. The lead-free gasoline of the present invention can be produced by blending 3 to 20% by volume of an alkylate or 1 to 10% by volume of a C4 fraction mainly composed of butane and butenes so as to satisfy the above properties. .

  Furthermore, various additives can be appropriately blended in the unleaded gasoline of the present invention as necessary. Such additives include phenolic and amine antioxidants, metal deactivators such as thioamide compounds, surface ignition inhibitors such as organophosphorus compounds, succinimides, polyalkylamines, polyetheramines. Detergents such as polyisobutylene amine, anti-freezing agents such as polyhydric alcohols and ethers thereof, organic metal alkali metal and alkaline earth metal salts, auxiliary alcohols such as higher alcohol sulfates, anionic surfactants, Known fuel additives include antistatic agents such as cationic surfactants and amphoteric surfactants, rust inhibitors such as alkenyl succinates, and colorants such as azo dyes. These can be added singly or in combination. The addition amount of these fuel additives is arbitrary, but usually the total addition amount is preferably 0.1% by mass or less.

  The content of the present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Examples 1 and 2
C4 fraction (butane, butenes) produced from catalytic cracking equipment, catalytic reforming equipment or atmospheric distillation equipment, debenzene catalytic reforming gasoline, debenzene light catalytic reforming gasoline, debenzene heavy weight with properties shown in Table 2 Gasoline reforming gasoline, catalytic cracking gasoline, alkylate, desulfurized light naphtha, and EtOH were blended at the blending ratios shown in Table 3 to obtain gasoline having the properties shown in Table 3.

Comparative Examples 1-3
C4 fraction (butane, butenes) described in Examples 1 and 2, debenzene catalytic reformed gasoline, debenzene light catalytic reformed gasoline, debenzene heavy catalytic reformed gasoline, catalytic cracked gasoline, alkylate, and By blending desulfurized light naphtha with the blending ratio shown in Table 3, gasoline having the properties shown in Table 3 was obtained.

  Various performance evaluation tests described below were performed using the gasoline obtained in the above Examples and Comparative Examples.

Startability, drivability, and demerit scores were evaluated using a 2L displacement, direct injection (DI), automatic transmission (AT) vehicle at a test temperature of 20 ° C and humidity of 50%.
These evaluations and test methods are described below, and the results are shown in Table 3.

(Startability)
The time from cranking start to complete explosion (time until the engine can continue to rotate by itself) was evaluated.
(Acceleration)
The engine was idled for 10 seconds after the engine was started, and the time until the vehicle speed reached 40 km / h with an accelerator opening of 50% was evaluated.
(Demerit points)
Evaluation was performed according to the CRC (Coordinating Research Council) Report No. 483 evaluation method.
The evaluation method was determined by the demerit score given by the degree of the phenomenon that occurred (Σ = demerit score × defect coefficient).
Note that stalls during idling and running were not calculated, and the respective coefficients were added. The smaller the score, the better the performance.

(Plug smoldering test)
Using a vehicle with a total displacement of 2L, MPI method, automatic transmission (AT), and a test temperature condition of -10 ° C, about 30 minutes per cycle (engine start ⇒ 10-20 km / h acceleration / deceleration repeated 10 times ⇒ 28 The degree of fouling of the plug was measured by measuring the insulation resistance of the plug. It was determined that plug smoldering occurred when the plug insulation resistance value was 100 MΩ or less.

  From the above results, it is clear that the unleaded gasoline of the present invention contains a specific amount of ethanol, is excellent in startability and operation performance, and can maintain the atmospheric environment while maintaining practical performance.

Claims (1)

Lead-free gasoline containing 1 to 15% by volume of ethanol (EtOH) and satisfying the following properties.
(1) Research method octane number (RON) is 89 or more and less than 97 (2) Motor method octane number (MON) is 79 or more and less than 87 (3) Reed vapor pressure (RVP) is 45 to 93kPa
(4) 50% distillation temperature (T50) is 75-110 ° C
(5) Distillation at 70 ° C (E70) is 18-40% by volume
(6) Distillation amount at 130 ° C. (E130) is 68 to 92% by volume
(7) Aromatic content 40% or less (8) Olefin content 30% or less (9) Benzene content 1% or less (10) Sulfur content 10 mass ppm or less