JP2000328078A - Gas oil composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the degradation in storage stability of a gas oil composition even when its sulfur content is extremely low by specifying its density, total aromatic content, sulfur content and Saybolt color. SOLUTION: This composition has a density at 15 deg.C of 0.80-0.85 g/cm3, a total aromatic content of 0-15 vol.%, a sulfur content of 0.005 mass % or lower and a Saybolt color of +10 or higher. Preferably, the fluorescent color strength index (provided the fluorescent color strength index of a standard n-hexane solution containing 1 mass ppm perylene is 10) of fluorescence of 435-550 nm developed by using excitation light of 390-470 nm according to the fluorescent color evaluation method for petroleum products described in Japan Kokai 1998-2861 is 10 or lower and/or the fluorescent color strength ratio (FClB/FClG) of a blue-range fluorescent color strength index (FClB) of the same fluorescence to the green-range fluorescent color strength index (FClG) of fluorescence of 490-550 nm is 0.5 or lower.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a gas oil composition,
More specifically, it relates to a gas oil composition having a low sulfur content.

[0002]

2. Description of the Related Art Diesel oil is a refined mineral oil of a suitable quality as a fuel for an internal combustion engine such as a diesel engine conforming to JIS K2204. Generally, gas oil is hydrodesulfurized kerosene. Typical composition and properties: Saturation content 70 to 90% by volume, aromatic content 10 to 30% by volume, sulfur content 0.002 to 0.005% by mass. And the density ($ 15
° C) of about 0.78 to 0.79 g / cm ³ , Saybolt color of about +30 to +35, fluorescent color intensity index value (FCI)
But about 0.3 to 0.5, a fluorescent color intensity ratio (FCI _B / FC
_IG ) is about 0.2 {hydrodesulfurized light gas oil} Typical composition and properties: 70 to 80% by volume of saturated component, 20 to 30% by volume of aromatic component, 0 content of sulfur component .03
0.05% by mass and a density (@ 15 ° C.) of 0.8
³ to 0.85 g / cm ³ , Saybolt color is 0 to +2
About 0, a fluorescent color intensity index value (FCI) is about 20 to 60, a fluorescent color intensity ratio (FCI _B / FCI _G) is from 0.4 to 0.
It is about 5 {direct light gas oil} Typical composition and properties:
Saturation content 60-80% by volume, olefin content 0
-3% by volume, aromatics content 20-40% by volume, sulfur content 0.001-0.005% by weight, and density (@ 15 ° C.) 0.84-0.87 g / cm ³ Degree, Saybolt color is about 0 to +20, fluorescent color intensity index value (FC
I) is about 10 to 30, a fluorescent color intensity ratio (FCI _B / FCI
_G ) is about 0.3 to 0.5, and the like is mixed.

In recent years, technologies of an exhaust gas recirculation system (EGR) and an oxidation catalyst have been adopted as a part of measures to reduce the exhaust gas of diesel vehicles. However, in these devices, when the sulfur content of light oil, which is the fuel, is high, the valve system of the engine is corroded due to the effect of sulfate ions generated by combustion, and the oxidation catalyst is poisoned and the purification rate is reduced. Have been reported to be caused. Therefore, when introducing these devices, the sulfur content in light oil is controlled worldwide, and even in Japan,
Regulations to reduce the sulfur content to 0.05% by mass or less have been strengthened since October, but further reduction of sulfur is under study.

[0004] Further reduction in the sulfur content of such gas oils involves increasing the severity of the reaction, such as an increase in the reaction temperature of hydrodesulfurization in which hydrotreatment is carried out in the presence of a catalyst. It can be achieved by desulfurizing a fraction having a low content of a sulfur compound (such as 4-methyldibenzothiophene or 4,6-dimethyldibenzothiophene) which is difficult to desulfurize under relatively low-severity conditions. However, if a light distillate such as kerosene is mixed in a large amount as a gas oil base material, the fuel density of diesel engines will deteriorate due to the decrease in the density of product gas oil, and the product balance will worsen, leading to an increase in manufacturing costs. Not a target. On the other hand, when hydrotreating under severe conditions such as deep desulfurization, there is a problem that unstable polycyclic aromatic compounds and the like are generated as the severity increases, and the storage stability of the product gas oil deteriorates. there were.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has been made in view of the above-mentioned problems, and is intended to provide a gas oil composition which does not deteriorate storage stability even when the sulfur content is significantly reduced. The purpose is to provide things.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, have found that the sulfur content is reduced and the density, the total aromatic content and the Saybolt color are specified. By satisfying the conditions, it has been found that a gas oil composition which does not deteriorate storage stability even when the sulfur content is significantly reduced can be obtained, and the present invention has been completed.

That is, the light oil composition of the present invention has a temperature of 15 ° C.
Is 0.80 to 0.85 g / cm ³ , the total aromatic content is 0 to 15% by volume, and the sulfur content is 0.1%.
005% by mass or less and the Saybolt color is +10
The above is the feature.

Further, in the light oil composition of the present invention, the light oil composition is developed using excitation light in the range of 390 to 470 nm, which is obtained in accordance with the method for evaluating the fluorescent color of petroleum products described in JP-A-10-2861. Fluorescence color intensity index value (FCI) for the fluorescence in the range of 435 to 550 nm (provided that
An n-hexane solution containing 1 mass ppm of perylene is used as a reference solution, and the fluorescent color intensity index value of the reference solution is set to 10).

Further, in the light oil composition of the present invention, the light oil composition is developed using excitation light in the range of 390 to 470 nm, which is obtained in accordance with the method for evaluating the fluorescent color of petroleum products described in JP-A-10-2861. The fluorescence color intensity ratio (FCI _B ) of the blue region fluorescent color intensity index value (FCIB) for the fluorescence range of 435 to 490 nm to the green region fluorescent color intensity index value (FCIG _G ) for the fluorescence range of 490 to 550 nm. _B
/ FCI _G) is preferably not more than 0.5.

[0010] Furthermore, in gas oil composition of the present invention, the above fluorescent color intensity index value (FCI) is 10 or less, and fluorescent color intensity ratio of the (FCI _B / FCI _G) 0.5 It is more preferred that:

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail.

The gas oil composition of the present invention must have a sulfur content of 0.005% by mass or less. If the sulfur content exceeds 0.005% by mass, the sulfur content will affect the latest diesel vehicle exhaust gas purification system, and the emission of environmental pollutants such as exhaust gas and PM (particulate matter) will increase. Becomes For the same reason, the sulfur content is preferably 0.003% by mass or less, more preferably 0.001% by mass or less. In addition, the sulfur content here means JISK
2541 means the sulfur content measured by the "Sulfur Content Test Method".

[0013] In the light oil composition of the present invention, 1
It is necessary that the density at 5 ° C. is 0.80 to 0.85 g / cm ³ . If the density is less than the above lower limit, the fuel consumption rate and the accelerating property are deteriorated due to the decrease in the density of the product gas oil (gas oil composition), and the product balance is deteriorated, leading to an increase in manufacturing cost. on the other hand,
If the density exceeds the above upper limit, the PM concentration in the exhaust gas increases, it becomes difficult to keep the total aromatic content at 0 to 15% by volume, and the Saybolt color and the fluorescent color intensity fall within a desired range. It is not preferable because it is difficult to obtain a product light oil having an index value and a fluorescent color intensity ratio, and even if the above-mentioned properties are within desired ranges, storage stability may be reduced. In addition, the density referred to here is JIS
K 2249 means the density measured according to “Density Test Method for Crude Oil and Petroleum Products and Conversion Table for Density / Mass / Volume”.

Further, in the light oil composition of the present invention, the content of the total aromatic component contained therein must be 0 to 15% by volume, preferably 0 to 12% by volume.
More preferably, it is 0 to 10% by volume. If the total aromatic content exceeds 15% by volume, the N
As the respective concentrations of Ox and PM increase, the storage stability of the product gas oil decreases.

Further, the content of the bicyclic aromatic component and the tricyclic aromatic component in the gas oil composition of the present invention is preferably 0.5% by volume or less and 0.1% by volume or less, respectively.
When the content of the bicyclic aromatic component and the tricyclic aromatic component exceeds the above upper limit, the coloring of the product gas oil tends to become strong, the storage stability tends to decrease, and the particulates in automobile exhaust gas ( (Particulate matter) tends to increase. Also,
From the same viewpoint, the content of the aromatic component having four or more rings is 0.1%.
% By volume or less, more preferably 0.04% by volume or less. In particular, a pentacyclic aromatic compound represented by perylene has a strong fluorescent color development property, and therefore it is desirable that the compound be as small as possible.

Further, the content of the saturated component in the gas oil composition of the present invention is preferably at least 85% by volume, more preferably at least 90% by volume, from the viewpoint of reducing the concentrations of NOx and PM in the exhaust gas. .

Further, the olefin content of the gas oil composition of the present invention is preferably 5% by volume or less, more preferably 3% by volume or less, from the viewpoint of the stability of the gas oil composition.
It is even more preferably 1% by volume or less.

Here, the total aromatic content is defined as
Japan Petroleum Institute Standard JPI-5S-49-97 "Petroleum products-
Hydrocarbon Type Test Method-High Performance Liquid Chromatography "
Means the volume percentage (% by volume) of the total aromatic component measured according to The saturated content and the olefin content are defined as the volume percentage (volume) of the saturated component and the olefin component measured in accordance with the fluorescent indicator adsorption method of “Petroleum products-component test method” specified in JIS K 2536. %)
Respectively.

Further, the content of each aromatic component as referred to herein means:
Aromatic Content Mass Analysis in Gas Oil (ASTM D32
39-76), and such an aromatic component is a partial aromatic component (alkylbenzene,
Naphthenebenzene, dinaphthenebenzene, etc.), bicyclic aromatics (naphthalene, acenaphthene, dibenzofuran, fluorene, etc.), tricyclic aromatics (phenanthrene, naphthenephenanthrene, etc.), tetracyclic aromatics (pyrene, chrysene, etc.) ), Pentacyclic aromatic components (perylene, dibenzoanthracene, etc.), and aromatic sulfur components (benzothiophene, dibenzothiophene, naphthodibenzothiophene, etc.).

In the light oil composition of the present invention, the Saybolt color needs to be +10 or more, and more preferably +15 or more. If the Saybolt color exceeds +10, the storage stability of the product gas oil decreases when the sulfur content is significantly reduced. Here, the Saybolt color means a value measured according to JIS K-2580.

Further, in the light oil composition of the present invention, the light oil composition is developed using excitation light in the range of 390 to 470 nm, which is obtained in accordance with the method for evaluating the fluorescent color of petroleum products described in JP-A-10-2861. Fluorescence color intensity index value (FCI) for the fluorescence in the range of 435 to 550 nm (provided that
The n-hexane solution containing 1 mass ppm of perylene is used as a reference solution, and the fluorescent color intensity index value of the reference solution is set to 10), preferably 10 or less, more preferably 5 or less. If the fluorescent color intensity index value exceeds 10, the storage stability of the product gas oil tends to decrease when the sulfur content is significantly reduced.

Further, in the light oil composition of the present invention,
Blue band fluorescent color intensity index values for the fluorescence in the range of 435~490nm obtained in the same manner 490～ of (FCI _B)
Fluorescent color intensity ratio green zone fluorescent color intensity index values for the fluorescence in the range of _{550nm (FCI G) (FCI B} / FCI
_G ) is preferably 0.5 or less, more preferably 0.2 or less. When the fluorescent color intensity ratio is 0.5
Also, when the sulfur content is significantly reduced, the storage stability of the product gas oil tends to decrease.

The fluorescent color intensity index values (FCI, FCI)
CI _B , FCI _G ) are specifically determined as follows. That is, 390～ as described in JP-A-10-2861 "fluorescent color evaluation method for petroleum products", from a light source (e.g., illuminant D ₆₅₎ using a spectrofluorimeter the sample (gas oil composition) Excitation light in the range of 470 nm is sequentially incident at predetermined intervals (for example, at 20 nm intervals), and the fluorescence spectrum (F (λ)) for each of the expressed excitation lights is measured. Then, from the measured fluorescence spectrum (F (λ)), the following formula: FCI = K × fci = K × Σ [I (a) × [∫ [F (λ) × y ₁₀ (λ)] dλ] ], A fluorescent color intensity index value is obtained.

In the above equation, F (λ) is the wavelength of the excitation light.
The fluorescence spectrum for each (λ), y ₁₀ (λ) is a color matching function of the X ₁₀ Y ₁₀ Z ₁₀ color system based on a 10-degree visual field (JIS Z8701).
−1995), I (a) is the wavelength of each excitation light (λ)
Relative spectral distribution value of the light source corresponding to (JIS Z8720
Fci is the integrated value of the fluorescent color intensity before correction, the integration range for the fluorescent color intensity index value (FCI) is 435 to 550 nm, and the blue color fluorescent color intensity index value (FCIB _B). ) Is 435-490n
m, the integration range of the green region fluorescent color intensity index value (FCI _G) is 490～550Nm. Also, K is the following equation: K = X / fci is a correction coefficient expressed by _st, perylene 1 mass p here
The a and 10 correction coefficient (K): containing pm n-hexane solution as a reference solution, of the reference solution fluorescence color intensity integral value fluorescent color intensity index value corresponding to the (fci _st) (X reference value) Used.

The distillation properties of the gas oil composition of the present invention are not particularly limited, but the following distillation properties: Initial boiling point: 135 to 200 ° C, 10% by volume Distillation temperature (T ₁₀ ): 155 to 240 ° C 30% by volume distillation temperature (T ₃₀ ): 175 to 270 ° C. 50% by volume distillation temperature (T ₅₀ ): 190 to 300 ° C. 70% by volume distillation temperature (T ₇₀ ): 220 to 330 ° C. 90% by volume distillation Temperature (T ₉₀ ): 250 to 350 ° C. 95% by volume Distillation temperature (T ₉₅ ): 270 to 360 ° C. Distillation end point: 280 to 370 ° C. is more preferable.

When the initial boiling point of the gas oil composition is too low,
The initial boiling point is preferably at least 135 ° C., more preferably, because some light fractions evaporate and the spray range becomes too wide, and the amount of hydrocarbons entrained in the exhaust gas tends to increase as unburned matter. 140 ° C. or higher, even more preferably 14 ° C.
5 ° C. or higher. On the other hand, if the initial boiling point is too high, there is a possibility of causing a problem in low-temperature startability and low-temperature operability, so the initial boiling point is preferably 200 ° C. or lower.

When T _{10 of the} gas oil composition is too low, there is a concern that the amount of hydrocarbons entrained in the exhaust gas may increase for the same reason as when the initial boiling point is too low. Therefore, T ₁₀ is preferably 155. C. or higher, more preferably 165.degree. C. or higher.
On the other hand, if T ₁₀ is too high, since it can cause trouble in the cold startability and low temperature operability, T ₁₀ 24
It is preferably 0 ° C. or lower.

The case T ₃₀ of the gas oil composition is too low, for the same reason as initial boiling point is too low, since the increase in the amount of hydrocarbons entrained in the exhaust gas is concerned, T ₃₀ is preferably 175 C. or higher, more preferably 180 ° C. or higher, even more preferably 185 ° C. or higher. On the other hand, if T ₃₀ is too high, since it can cause trouble in the cold startability and low temperature operation, it is preferable T ₃₀ is 270 ° C. or less.

The T _{50 of the} gas oil composition is preferably 190 ° C. or higher, more preferably 195 ° C. or higher, and even more preferably 200 ° C., from the viewpoint of fuel consumption rate and engine output.
That is all. On the other hand, it is preferable from the viewpoint of not increasing the PM concentration in the exhaust gas, T ₅₀ is 300 ° C. or less.

The T _{70 of the} gas oil composition, like the T ₅₀ , tends to affect the fuel consumption rate and the engine output. Therefore, T ₇₀ is preferably 220 ° C. or higher, more preferably 225 ° C. or higher, and even more preferably 230 ° C., in order to further improve the fuel consumption rate and the engine output.
° C or higher. On the other hand, it is preferable from the viewpoint of not increasing the PM concentration in the exhaust gas, T ₇₀ is 330 ° C. or less.

T _{90 of the} light oil composition is preferably 250 ° C. or higher, more preferably 270 ° C. or higher, from the viewpoint of lubricity in the fuel injection pump. On the other hand, P in exhaust gas
From the viewpoint of not increasing the M concentration, T ₉₀ is preferably 350 ° C. or less.

[0032] T ₉₅ of the gas oil composition, from the viewpoint of lubricity in fuel injection pump, is preferably 270 ° C. or higher. On the other hand, if _T95 is too high, the exhaust gas and PM emission tend to increase, so that _T95 is preferably 360 ° C or lower.

The distillation end point of the gas oil composition is preferably at least 280 ° C. from the viewpoint of lubricity in the fuel injection pump. On the other hand, from the viewpoint of not increasing the PM concentration in the exhaust gas, the distillation end point is preferably 370 ° C. or lower.

The distillation properties (the initial boiling point,
_{T 10, T 30, T 50} , T 70, T 90, T 95, and the distillation end point), all JIS K 2254 - refers to a value measured according to "Petroleum products distillation test method".

The kinematic viscosity of the light oil composition of the present invention is not particularly limited. However, from the viewpoint of control of the fuel injection timing and lubricity of the distribution type fuel injection pump attached to the engine, the kinematic viscosity at 30 ° C. is preferably 1.7 mm ² / s or more, and 1.9 mm ² / s. It is more preferably at least 2.0 mm ² / s. On the other hand, from the viewpoint of not increasing the PM concentration in the exhaust gas and reducing the influence on the starting performance at low temperatures, the kinematic viscosity at 30 ° C. is 6.0 mm ² /
s or less, more preferably 5.0 mm ² / s or less, and even more preferably 4.5 mm ² / s or less. Here, the kinematic viscosity means a kinematic viscosity measured in accordance with JIS K 2283 "Crude oil and petroleum products-Kinematic viscosity test method and viscosity index calculation method".

The cetane number and cetane index of the gas oil composition of the present invention are not particularly limited. However, from the viewpoint that each concentration of NOx, PM and aldehyde in the exhaust gas can be further reduced, the cetane number is preferably 45 or more,
More preferably 48 or more, even more preferably 50 or more, and the cetane index is preferably 45 or more, more preferably 48 or more, and even more preferably 50 or more. In addition, the cetane number mentioned here is JIS K22
80 means the cetane number measured according to "7. Cetane number test method" of "Petroleum products-Fuel oil-Octane number and cetane number test method and cetane index calculation method". The cetane index is calculated in accordance with JIS K 2280 “Method for calculating cetane index using 8.4 variable equation” in “Petroleum products-Fuel oil-Test method for octane number and cetane number and calculation method for cetane index”. Mean value.

The gas oil composition of the present invention has a pour point (P
There is no particular limitation on P). However, the pour point is preferably 0 from the viewpoint of low temperature startability or low temperature operation.
° C or lower, more preferably -5 ° C or lower, and even more preferably -10 ° C or lower. Here, the pour point means a pour point measured in accordance with JIS K 2269 "Testing methods for pour point of crude oil and petroleum products and cloud point of petroleum products".

Similarly, the gas oil composition of the present invention has no particular restriction on the clogging point (CFPP). However, in general, the clogging point is preferably 0 ° C or less, more preferably -5 ° C or less, and even more preferably -10 ° C.
° C or lower, particularly preferably -20 ° C or lower. The term "clogging point" as used herein means a clogging point measured in accordance with JIS K 2288 "Light Oil-Clogging Point Test Method".

Similarly, there is no particular limitation on the cloud point (CP) of the gas oil composition of the present invention. But,
Generally, the cloud point is preferably 0 ° C. or less. Here, the cloud point means a pour point measured according to JIS K 2269 "Pour point of crude oil and petroleum products and cloud point test method of petroleum products".

Further, the light oil composition of the present invention is preferably HF from the viewpoint of sufficiently maintaining the effect of adding a lubricity improver described below.
The wear scar diameter in the RR test is preferably 550 μm or less, more preferably 500 μm or less. In addition, the wear scar diameter in the HFRR test here means a wear scar diameter measured based on the Japan Petroleum Institute method JPI-5S-50-98 "light oil-lubricity test method".

The light oil composition of the present invention can be obtained by blending additives and the like as necessary with light oil (base light oil). The base gas oil according to the present invention is not particularly limited as long as the obtained gas oil composition satisfies the above conditions, and its production method and the like are not particularly limited, and one or more of the following gas oil base materials are appropriately selected and mixed. It is possible to get. Specific examples of the gas oil base material that can be used in the present invention include, for example, a straight-run gas oil obtained from an atmospheric distillation apparatus for crude oil;
Vacuum gas oil obtained by subjecting a straight-run heavy oil or residue obtained from an atmospheric distillation unit to a vacuum distillation unit; hydrorefined gas oil obtained by hydrorefining a vacuum gas oil obtained from a vacuum distillation unit; straight-run gas oil Hydrodesulfurized gas oil obtained by hydrodesulfurization in one or more stages under severer conditions than ordinary hydrorefining; obtained by catalytic cracking of desulfurized or undesulfurized vacuum gas oil, vacuum heavy gas oil or desulfurized heavy oil Catalytic cracked gas oil; straight kerosene obtained by atmospheric distillation of crude oil; hydrorefined kerosene obtained by hydrorefining straight kerosene; obtained by cracking a gas oil fraction obtained by atmospheric distillation of crude oil Decomposed kerosene and the like.

For example, the base gas oil according to the present invention may be a hydrodesulfurized kerosene obtained by hydrodesulfurizing a straight-run kerosene obtained from an atmospheric distillation column, and a ultra-deep hydrogen gas having a sulfur content of 0.005% by mass or less. Hydrodesulfurized light gas oil obtained by hydro-desulfurization is mainly used, and if necessary, light cycle oil obtained from fluid catalytic cracking unit and / or residual oil fluid catalytic cracking unit is hydrodesulfurized. It can be produced by mixing direct desulfurized gas oil obtained from a heavy oil desulfurization unit.

More specifically, a straight-run hydrogenated light having a sulfur content of 0.005% by mass or less and a density (＠ 15 ° C.) of 0.82 to 0.84 g / cm ³ , which has been subjected to ultra-deep desulfurization treatment. Light oil,
Hydrogenated kerosene having a density (＠ 15 ° C.) of 0.78 to 0.79 g / cm ³ , a sulfur content of 0.001 to 0.005% by mass, and a density (＠ 15 ° C.) of 0.84 to 0 0.87 g / cm ³ of directly removed light oil with a density (＠ 15 ° C.) of 0.80 to 0.85 g / c
It is manufactured by adjusting and mixing m ³ and the total content of aromatic hydrocarbon components to 15% by volume or less of the gas oil composition. The gas oil composition of the present invention thus obtained is particularly useful as a gas oil composition as a diesel fuel.

It should be noted that the ultra-deep hydrodesulfurization light gas oil may be prepared, for example, at a reaction temperature of 320-380 ° C. and a pressure of 4-7
MPa, LHSV 0.5-3h- ¹ , hydrogen / oil ratio 500-
2000 scfb, and the second step is performed at a reaction temperature of 320 to
380 ° C, pressure 10-15MPa, LHSV 0.5-2
The sulfur content of the DC light gas oil is reduced to 0.005 mass% or less by the hydrodesulfurization method with h ^-1 and a hydrogen oil ratio of 1000 to 5000 scfb, but these conditions are not particularly limited.

The additives which can be used in the light oil composition of the present invention include lubricity improvers, cetane improvers, detergents and the like. Such additives are used alone or in combination of several kinds for the purpose of further enhancing the expected performance, and among them, it is preferable to contain at least a lubricity improver.

As the lubricity improver according to the present invention, for example, one or more of carboxylic acid type, ester type, alcohol type and phenol type lubricity improvers can be arbitrarily used. Among these, carboxylic acid-based and ester-based lubricity improvers are preferred.

Examples of the carboxylic acid-based lubricity improver include linoleic acid, oleic acid, salicylic acid, palmitic acid, myristic acid, hexadecenoic acid and a mixture of two or more of the above carboxylic acids. Examples of the ester-based lubricity improver include carboxylate of glycerin. The carboxylic acid constituting the carboxylic acid ester may be one kind or two or more kinds, and specific examples thereof include linoleic acid, oleic acid,
Salicylic acid, palmitic acid, myristic acid, hexadecenoic acid and the like.

The content of such a lubricity improver is not particularly limited. However, in order to bring out the effect of the lubricity improver, specifically, in a diesel engine equipped with a distribution type injection pump, in order to suppress the increase in the driving torque of the running pump and reduce the wear of the pump, Is 35 mass ppm based on the total amount of the composition.
Or more, more preferably 50 mass ppm or more. On the other hand, the compounding amount of the lubricity improver is
Since an effect commensurate with the amount of addition cannot be obtained even if it is added more than 150 mass ppm or less is preferable.
More preferably, it is not more than 00 mass ppm.

Commercially available products called lubricity improvers are generally obtained in a state where active ingredients contributing to the improvement of lubricity are diluted with an appropriate solvent. When such a commercially available product is blended with the light oil composition of the present invention, the blending amount described above for the lubricity improver means the blending amount as an active ingredient.

Further, as the cetane number improver according to the present invention, various compounds known in the art as cetane number improvers can be arbitrarily used. For example, nitrate esters and organic peroxides can be used. It is possible, and among them, it is preferable to use a nitrate ester. For nitrate ester, 2-
Chloroethyl nitrate, 2-ethoxyethyl nitrate, isopropyl nitrate, butyl nitrate, primary amyl nitrate, secondary amyl nitrate, isoamyl nitrate, primary hexyl nitrate, secondary hexyl nitrate, n- Various nitrates such as heptyl nitrate, n-octyl nitrate, 2-ethylhexyl nitrate, cyclohexyl nitrate and ethylene glycol dinitrate are included. Among these, alkyl nitrates having 6 to 8 carbon atoms are preferable. As the cetane number improver, one kind of a single compound may be used, or two or more kinds of compounds may be used in combination.

The content of the cetane number improver in the gas oil composition of the present invention is 500 ppm by mass based on the total amount of the composition since the NOx concentration, the PM concentration, the aldehyde concentration and the like of the diesel engine exhaust gas can be further reduced.
It is preferably at least 600 ppm by mass, more preferably at least 600 ppm by mass, still more preferably at least 700 ppm by mass, particularly preferably at least 800 ppm by mass, most preferably at least 900 ppm by mass. preferable.

The upper limit of the content of the cetane number improver is not particularly limited, but generally, the content of the cetane number improver is preferably 1400 ppm by mass or less based on the total amount of the gas oil composition, and is preferably 1250 ppm or less. It is more preferably at most 1 ppm by mass, more preferably at most 1100 ppm by mass, most preferably at most 1000 ppm by mass.

Commercially available products called cetane improvers are usually obtained in the form of an active ingredient contributing to cetane improve, that is, diluted with an appropriate solvent. is there. When the gas oil composition of the present invention is prepared using such commercially available products, the content described above with respect to the cetane number improver means the content as an active ingredient.

Examples of the detergent according to the present invention include:
Imide compounds; alkenyl succinimides such as polybutenyl succinimide synthesized from polybutenyl succinic anhydride and ethylene polyamines; synthesized from polyhydric alcohols such as pentaerythritol and polybutenyl succinic anhydride Succinates such as polybutenyl succinates; copolymers such as dialkylaminoethyl methacrylate, polyethylene glycol methacrylate, copolymers of vinylpyrrolidone and the like with alkyl methacrylates, and succinates such as reaction products of carboxylic acids and amines. Ash detergents. Such detergents can be used alone or in combination of two or more. Among them, the use of a reaction product of an alkenyl succinimide and a carboxylic acid with an amine is preferable.

Examples of the use of alkenyl succinimide include the case where alkenyl succinimide having a molecular weight of about 1,000 to 3,000 is used alone and the case where the molecular weight is about 700 to 2,000.
Alkenyl succinimide of about 000 and molecular weight of 100
Alkenyl succinimides of about 00 to 20000 may be mixed and used.

The carboxylic acid constituting the reaction product of the carboxylic acid and the amine may be one kind or two or more kinds, and specific examples thereof include a fatty acid having 12 to 24 carbon atoms and a fatty acid having 7 carbon atoms. To 24 aromatic carboxylic acids.
Examples of the fatty acid having 12 to 24 carbon atoms include, but are not limited to, linoleic acid, oleic acid, palmitic acid, and myristic acid. In addition, carbon number 7
Examples of the aromatic carboxylic acids (1) to (24) include, but are not limited to, benzoic acid and salicylic acid. The amine constituting the reaction product of the carboxylic acid and the amine may be one type or two or more types.
As the amine used here, oleylamine is typical, but not limited thereto, and various amines can be used.

The blending amount of the detergent in the light oil composition of the present invention is not particularly limited. However, in order to bring out the effect of blending the detergent, specifically, the effect of suppressing the clogging of the fuel injection nozzle, the blending amount of the detergent should be 30% based on the total amount of the composition.
Mass ppm or more, preferably 60 mass ppm
More preferably, it is more preferably 80 mass ppm or more. Even if an amount less than 30 ppm by mass is added, the effect may not be exhibited. On the other hand, if the blending amount is too large, a corresponding effect cannot be expected. Conversely, NOx, P
Because it may increase M, aldehyde, etc.
The amount of the detergent is preferably 300 mass ppm or less, more preferably 180 mass ppm or less.

As in the case of the cetane number improver,
Commercially available products called detergents are generally obtained in a state where active ingredients contributing to cleaning are diluted with an appropriate solvent. When such a commercially available product is blended with the light oil composition of the present invention, the blending amount described above for the detergent means the blending amount as an active ingredient.

Further, in the light oil composition of the present invention,
For the purpose of further enhancing other performances, other known fuel oil additives can be added alone or in combination of several kinds. Examples of such additives include low-temperature fluidity improvers such as ethylene-vinyl acetate copolymer and alkenyl succinamide; phenol-based and amine-based antioxidants; and metal deactivators such as salicylidene derivatives. Anti-icing agents such as polyglycol ether; corrosion inhibitors such as aliphatic amines and alkenyl succinates;
Antistatic agents such as cationic and amphoteric surfactants; coloring agents such as azo dyes; defoaming agents such as silicones;
The amount of these other additives is not particularly limited,
The amount of each additive is 0.5% by mass based on the total amount of the gas oil composition.
Or less, more preferably 0.2% by mass or less.

[0060]

EXAMPLES Hereinafter, the content of the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

Examples 1 to 5 and Comparative Examples 1 to 3 Light oil base materials shown in Table 1 were mixed at a mixing ratio shown in Table 2, and
A gas oil composition having the composition, distillation properties and various properties shown in Table 1 was prepared. Each of the obtained light oil compositions was subjected to the following storage stability test and lubricity test. In Examples 1 to 5, a fatty acid ester-based compound (100 ppm) was further added as a lubricity improver to each of the above light oil compositions, and a lubricity test was also performed on the light oil composition containing the lubricity improver. Was. Table 2 shows the obtained results.

The fluorescent color intensity index value and the fluorescent color intensity ratio are as follows: Spectrophotometer: F-4010 type light source manufactured by Hitachi, Ltd. Light source: D ₆₅ Excitation wavelength interval: 20 nm Color matching function: Appendix of JIS Z8701-1995 Value shown in 2 Relative spectral distribution value of light source: Value shown in Appendix Table 1 of JIS Z8720-1983 Reference solution: n-hexane solution containing 1 mass ppm of perylene Fluorescent color intensity index value of reference solution (reference value: X): 10 Correction coefficient: measured under 0.00042 in accordance with “Method for evaluating fluorescent color of petroleum products” described in JP-A-10-2861.

The conditions for hydrodesulfurization of the ultra-deep hydrodesulfurized light gas oil used are as follows: (Ultra deep hydrodesulfurized light gas oil-1) Reaction temperature: 340 ° C., reaction pressure: 12.2 MPa, Liquid hourly space velocity: 0.98 h ^-1 , Hydrogen oil ratio: 2050 SCF / b
bl (Ultra deep hydrodesulfurization light gas oil-2) Reaction temperature: 340 ° C, Reaction pressure: 12.2 MPa, Liquid hourly space velocity: 1.01 h ^-1 , Hydrogen oil ratio: 2050 SCF / b
bl (Ultra deep hydrodesulfurization light gas oil-3) Reaction temperature: 380 ° C, Reaction pressure: 5.0 MPa, Liquid hourly space velocity: 2.47 h ^-1 , Hydrogen oil ratio: 1993 SCF / bb
l.

[0064] (1) lubricity test Petroleum Institute Method JPI-5S-50-98 - in compliance with the "diesel lubricity test method", was measured the wear scar diameter in HFRR test.

(2) Storage stability test Each sample was dried at 80 ° C. for 1 week with a dryer, and the Saybolt color and the gum content were measured. The measurement of the gum content was performed by the following method. That is, 100 ml of the dried sample is taken out, cooled to room temperature, and then suction-filtered through a crucible containing two glass fiber filter papers. Further, while washing the sample solution with isooctane, the washing solution is subjected to suction filtration. Next, after newly replacing the suction bottle, the amount of gum adhering to the sample container is reduced by 5%.
Wash and dissolve with a mixed solvent of equal to or less than 0 ml of methanol / acetone / toluene (hereinafter referred to as "gum solvent"), and suction-filter the washing liquid. Then, the liquid in the suction bottle is taken into a real gum measuring container, and the air injection method (JIS K2
261 "according to gasoline and aviation fuel oil real gum test method") to evaporate the gum solvent and weigh the remaining gum.

[0066]

[Table 1]

[0067]

[Table 2]

As is clear from the results shown in Table 2, the light oil composition according to the present invention has excellent storage stability even when the sulfur content is reduced to 0.005% by mass or less. Was something.

[0069]

As described above, according to the light oil composition of the present invention, it is possible to sufficiently prevent storage stability from being deteriorated even when the sulfur content is significantly reduced.
Therefore, according to the present invention, it is possible to obtain an optimal light oil composition corresponding to high performance and electronic control of a diesel vehicle.

Claims (4)

[Claims] A density at 15 ° C. of 0.80 to 0.8
5 g / cm ³ , the total aromatic content is 0 to 15% by volume
Wherein the sulfur content is 0.005% by mass or less, and the Saybolt color is +10 or more. 2. 390-400 obtained according to the method for evaluating the fluorescent color of petroleum products described in JP-A-10-2861.
435-expressed using excitation light in the range of 470 nm
Fluorescence color intensity index value (FCI) for fluorescence in the range of 550 nm (however, n containing 1 mass ppm of perylene)
The light oil composition according to claim 1, wherein the hexane solution is used as a reference solution, and the fluorescent color intensity index value of the reference solution is 10 or less. 3. A stone described in JP-A-10-2861.
390-obtained in accordance with the fluorescent color evaluation method for oil products
435-expressed using excitation light in the range of 470 nm
Blue region fluorescent color intensity index for fluorescence in the 490 nm range
Value (FCI_B) In the range of 490 to 550 nm.
Green color intensity index value (FCI _GFluorescence for
Color intensity ratio (FCI_B/ FCI_G) Is 0.5 or less
The gas oil composition according to claim 1, characterized in that: 4. 390-400 obtained according to the fluorescent color evaluation method for petroleum products described in JP-A-10-2861.
435-expressed using excitation light in the range of 470 nm
Fluorescence color intensity index value (FCI) for fluorescence in the range of 550 nm (however, n containing 1 mass ppm of perylene)
Hexane solution as a reference solution, and the fluorescent color intensity index value of the reference solution is 10) or less, and 43
Blue band fluorescent color intensity index values for the fluorescence in the range of 5~490nm green zone fluorescent color intensity index values for the fluorescence in the range of 490~550nm of (FCI _B) fluorescent color intensity ratio (FCI _G) (FCI _B / The gas oil composition according to claim 1, wherein FCI _G ) is 0.5 or less.