JP2000204383A - Gasoline - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gasoline generating exhaust gas containing little harmful components, i.e., hydrocarbons(HC) and carbon monoxide(CO), having excellent acceleration performance even in the state of cold car engine and causing little deposition in the combustion chamber of the engine. SOLUTION: The objective gasoline has an octane number of >=96, an aromatic hydrocarbon content of <=45 vol.%, a 50% distillation temperature (abbreviated as T50) of 75-99 deg.C, a T70/T50 ratio of 1.2-1.0 (T70 is 70% distillation temperature), a T90/T50 ratio of 1.45-1.0 (T90 is 90% distillation temperature) and a T90/T70 ratio of 1.2-1.0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high octane gasoline which is excellent in acceleration performance and exhaust gas performance when a vehicle is cold and which can reduce deposits in a combustion chamber.

[0002]

2. Description of the Related Art An automobile engine is manufactured using carbon monoxide (C).
O) and hydrocarbons (HC). For this reason, modern automobile engines have a system that precisely controls the ratio of air and gasoline to efficiently remove these harmful components with a catalyst, or to promote combustion by air flow called squish flow. A narrow space called a squish area is provided in the combustion chamber. As a fuel suitable for a recent engine having a system for precisely controlling the ratio of air to gasoline, a gasoline production method as disclosed in JP-A-4-320492 and JP-A-9-95688 has been proposed.

[0003]

However, the conventionally proposed gasoline is not sufficient to exhibit the performance of the new engine. For example, there is a case where low-speed acceleration required especially for the fuel of an automobile is low, or the amount of deposit (CCD) in the combustion chamber is increased. When this deposit increases, the deposit adheres to the above-mentioned squish area to generate abnormal noise, and knocking easily occurs due to the heat insulating effect of the deposit. For this reason, there has been a demand for gasoline that can reduce harmful components in exhaust gas, particularly HC and CO, satisfy acceleration performance required for vehicle cooling when the vehicle is cold, and generate less deposits.

It is an object of the present invention to provide (1) exhaust gas, especially H
It is an object of the present invention to provide gasoline that generates less C and CO, (2) satisfies the acceleration performance when the vehicle is cold, and (3) generates less deposit.

[0005]

Means for Solving the Problems The present inventor has made intensive studies to solve the above problems, and as a result,
When a gasoline composition having a specific composition and properties was used, it was found that the harmful components in the exhaust gas were reduced, the acceleration performance during vehicle cooling was improved, and the generation of deposits was reduced, and the present invention was reached. .

[0006] The gasoline according to the present invention has specific distillation properties and aromatic hydrocarbon content. That is, the gasoline according to the present invention is a gasoline having an octane number of 96 or more and an aromatic hydrocarbon content of 45% by volume or less, and has a 50% distillation temperature (hereinafter, referred to as T50).
Is 75 ° C. to 99 ° C., and the 70% distillation temperature (hereinafter, T7
0) and T50 of T70 / T50 of 1.2 to 1.
0, 90% distillation temperature (hereinafter referred to as T90) and T
The ratio T90 / T50 of 1.50 is 1.45 to 1.0, and the ratio T90 / T70 of T90 to T70 is 1.2 to 1.
0. Further, the gasoline according to the present invention comprises (A) a fluid catalytic cracking gasoline containing at least a fraction having a boiling point in the range of 40 ° C to 70 ° C, and (B) a toluene concentration of 60%.
It is preferable to contain the above-mentioned catalytic reforming gasoline, and further contain (C) alkylate.

The gasoline of the present invention has an octane number of 96 or more,
The gasoline is preferably 98 or more, and is gasoline capable of sufficiently exhibiting the performance of a high-performance engine having a high compression ratio.
This octane number is a value measured by the method specified in “Octane number test method” of “JIS K 2280”.

[0008] The 50% distilling temperature of the gasoline of the present invention is 75 to 9 from the viewpoint of acceleration performance, especially when the vehicle is cold.
It must be 9 ° C. If the 50% distillation temperature exceeds 99 ° C., the acceleration performance when the vehicle is cold deteriorates. Also, 50%
If the distilling temperature is lower than 75 ° C., vapor lock, percolation, and the like may occur, which may adversely affect the heat resistance performance, and may cause the vaporizer to freeze on a vaporizer-specification vehicle. From this viewpoint, the 50% distillation temperature is 77 to 99 ° C,
More preferably, the temperature is set to 80 to 96 ° C.

Further, the distillation properties of the tail fraction such as T70 and T90 are not inferior to T50 and have a great influence on the acceleration performance and exhaust gas performance when the vehicle is cold, and it is preferable to flatten T50, T70 and T90, and to improve the octane number. T70 / T50 = 1.2- after balancing other properties
1.0, T90 / T50 = 1.45 to 1.0, T90 /
T70 = 1.20 to 1.0 is appropriate. Particularly preferably, T70 / T50 = 1.2 to 1.1, T90 / T50
= 1.40-1.20, T90 / T70 = 1.20
It is in the range of 1.05. From the viewpoint of combustion chamber deposit, T90 is particularly important, and T90 / T50 = 1.
Setting the ratio to 45 to 1.0 is effective for reducing the deposit in the combustion chamber. The distillation property referred to in the present invention is "JIS K 2
254 "means the value measured by the method specified in" Fuel oil distillation test method ".

With respect to the content of the aromatic component, the gasoline of the present invention must have an aromatic component content of 45% by volume or less, more preferably 25 to 35% by volume. When the content of the aromatic component exceeds 45% by volume, the components used in the gasoline system of the automobile may be adversely affected or the spark plug may be smoldered. Here, the content of the aromatic component is a value measured by the “fuel hydrocarbon component test method (fluorescent indicator adsorption method)” specified in “JISK 2536”.

In order to produce gasoline having such properties, for example, the following base materials can be mixed. The kind and properties of the substrate suitable for carrying out the present invention will be described. The components of this preferred substrate comprise the following components (A) and (B), and furthermore, component (C).

Component (A): Boiling point at least 40 ° C.
Fluid catalytic cracked gasoline containing a fraction in the range of 70 ° C. Component (B): catalytic reformed gasoline having a toluene concentration of 60% or more Component (C): alkylate (A) The fluid catalytic cracked gasoline used in the present invention includes: Fluid catalytic cracking gasoline obtained by cracking a wide range of petroleum fractions from kerosene gas oil to atmospheric residual oil, preferably heavy gas oil or vacuum gas oil, with a fluid catalytic cracking method using a solid acid catalyst. 89-92, initial boiling point 25-40 ° C, 90% distillation temperature 160-190 ° C
Is preferred.

(A) The fluid catalytic light cracked gasoline includes a wide range of petroleum fractions ranging from kerosene gas oil to atmospheric residual oil,
Preferably, a light fraction of a catalytic cracking gasoline base material obtained by cracking heavy gas oil or vacuum gas oil with a solid acid catalyst by a fluid catalytic cracking method is preferably used. The research octane number of this light distillate is 92-97 and the initial distillate is 25.
It is preferable that the 90% distillation temperature is 70 to 90 ° C. Further, the content of (A) the fluid catalytic cracked gasoline in gasoline is preferably 1 to 50% by volume, more preferably 20 to 40% by volume.

(B) Catalytic reforming gasoline is obtained by conventionally known catalytic reforming method of heavy straight-run naphtha and the like, and is a base material having a toluene concentration of 60% or more. In such a base material, a distillate having a carbon number higher than 8 (a distillate having a boiling point higher than about 140 ° C.) is removed from the normally obtained catalytic reforming gasoline by distillation to adjust the toluene concentration to 60 to 80%. Or the catalytic reforming gasoline from which the distillate heavier than C8 has been removed, further distilling off the forehead (fraction having a boiling point lower than about 100 ° C.) to obtain a toluene concentration of 85% or more, especially Is preferably 87% to 95%. In the present invention, the content of the component (B) is 1 to 50% by volume.
, And particularly preferably 30 to 50% by volume.

(C) Alkylate is obtained by reacting isobutane and a lower olefin (such as butene and propylene) in the presence of an acid catalyst (such as sulfuric acid, hydrofluoric acid and aluminum chloride). . In the present invention, various alkylates can be used,
Those containing 60% by volume or more of isooctane are preferable, and particularly those having a research octane number of 92 or more can be suitably used. The content of the component (C) is 1 to 6
It is preferably 0% by volume, more preferably 10 to 30% by volume, and particularly preferably 15 to 25% by volume.

Of course, as long as the above components have the same properties, they can be used irrespective of the production method. In addition to the above components, 0 to 15% by volume of straight-run naphtha and MTBE (methyl-te
0 to 15% by volume of an oxygen-containing compound such as rt-butyl ether), and 0 to 8% by volume of a fraction having 4 carbon atoms in order to secure the vapor pressure and keep the startability of the engine good. .

Further, one or more fuel oil additives known in the art can be blended with the gasoline of the present invention, if necessary. The amounts of these additives can be appropriately selected, but it is usually preferable to maintain the total amount of additives at 0.1% by weight or less. Examples of fuel oil additives that can be used in the gasoline of the present invention include phenol-based, amine-based antioxidants, Schiff-type compounds, metal deactivators such as thioamide-type compounds, and organic phosphorus-based compounds. 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 flame retardants such as esters, anionic surfactants, cationic surfactants, antistatic agents such as amphoteric surfactants, and coloring agents such as azo dyes.

[0018]

EXAMPLES Hereinafter, the structure and effects of the present invention will be described more specifically with reference to Examples and Comparative Examples, but these do not limit the present invention at all.

[Exhaust Gas Test] Among the test vehicle types shown in Table 1, using a Diamante manufactured by Mitsubishi Motors Corporation, an exhaust gas test was performed in 10.15 mode and 11 mode. The measurement items were carbon monoxide, total hydrocarbons, and nitrogen oxide concentrations.

[0020]

[Table 1]

[Acceleration test] Crowns manufactured by Toyota Motor Corporation shown in Table 1 were used. For the acceleration during cold operation, the test vehicle was placed in a constant temperature room and left at a constant temperature of 25 ° C. for 24 hours. Then, the engine of the test car was started on the chassis dynamo (load condition was set to road load), and 1/4
The time required to accelerate from 0 to 120 km / h at the throttle opening was measured and evaluated. The warm-up acceleration is
After sufficient warm-up, the engine was restarted and tested as described above.

[Deposit (CCD) generation test] The commercially available engines shown in Table 1 were installed on an engine bench, operated continuously at an engine speed of 2200 rpm and a torque of 3.3 kgfm for a total of 50 hours. The accumulated deposit was collected and weighed.

[Production of Gasoline and Test Results] Each gasoline base material shown in Table 2 was mixed at a mixing ratio shown in Tables 3 and 4, and gasoline of each Example and Comparative Example was produced. In Table 2, the catalytic reforming gasoline 70 is a base material containing 70% by volume of toluene, and the catalytic reforming gasoline 90 is a substrate containing 90% by volume of toluene. Catalytic reforming gasoline b
Is a base material obtained by cutting 15% of the fore-run and 80% of the back-run of the catalytic reforming gasoline a by distillation. The catalytic reforming gasoline a is a base material containing 25% by volume of toluene, and the catalytic reforming gasoline b is a base material containing 38% by volume of toluene.

[0024]

[Table 2]

[0025]

[Table 3]

[0026]

[Table 4]

Tables 5 and 6 show the density, distillation properties, research octane number, and proportion of aromatic hydrocarbons of each gasoline.

[0028]

[Table 5]

[0029]

[Table 6]

The gasoline of each of the Examples and Comparative Examples was subjected to the above-described exhaust gas test, acceleration test, and deposit generation test. The test results are shown in Tables 7, 8 and 9.

[0031]

[Table 7]

As is clear from Table 7, the components contained in the exhaust gas include carbon monoxide (CO) and hydrocarbon (HC).
Decreased. When compared with the gasoline of the comparative example, the value was clearly lower.

[0033]

[Table 8]

Table 8 shows the results of the acceleration performance. From the results of using Examples 1 to 5 and Comparative Examples 1 to 4, good acceleration during vehicle cooling can be obtained when the 50% distillation temperature is in the range of 75 to 99 ° C, preferably 86 to 97 ° C. In addition, T7
0 / T50, T90 / T50, T90 / T70
T70 / T50 = 1.20 or less, T90 / T50 = 1.
It can be seen that good acceleration during cold vehicle operation and good exhaust performance can be obtained when T90 / T70 = 1.20 or less.

[0035]

[Table 9]

As can be seen from these results, the gasoline of the present invention has a low generation amount of harmful components in the exhaust gas, and has excellent acceleration performance both at the time of cooling and at the time of warming. Very good. Further, as can be seen from Table 9, the deposit (CCD) has T90 / T50
It can be seen that the deposit amount decreases with decreasing T90 / T70.

[0037]

The present invention provides a gasoline having a specific aromatic content and a specific distillation property.
As a result, as compared with conventional gasoline, the acceleration performance when the vehicle is cold is good, the amount of harmful components generated in the exhaust gas is low, and this is extremely advantageous for pollution control. Therefore, the gasoline of the present invention is expected to be widely and effectively used as a fuel oil for gasoline engines having low pollution and high performance.

Claims (3)

[Claims] 1. A gasoline having an octane number of 96 or more and an aromatic hydrocarbon content of 45% by volume or less, wherein a 50% distillation temperature (hereinafter, referred to as T50) is 75 ° C. to 99 ° C.
° C, and the ratio T of 70% distillation temperature (hereinafter referred to as T70) to T50.
70 / T50 is 1.2 to 1.0, and the ratio T of 90% distillation temperature (hereinafter referred to as T90) to T50
90 / T50 is 1.45 to 1.0, and the ratio T90 / T70 of T90 and T70 is 1.2 to
Gasoline characterized by being 1.0. (A) a boiling point of at least 40 ° C. to 70 ° C.
2. The gasoline according to claim 1, wherein the gasoline contains a fluid catalytic cracking gasoline containing a fraction in the range of ° C and (B) a catalytic reforming gasoline having a toluene concentration of 60% or more. (A) a boiling point of at least 40 ° C. to 70 ° C.
2. A gasoline according to claim 1, wherein the gasoline contains a fluidized catalytic cracking gasoline containing a fraction in the range of ° C, (B) a catalytic reforming gasoline having a toluene concentration of 60% or more, and (C) an alkylate. .