JP2013040283A - Kerosene composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a kerosene composition excellent in storage stability that comprises using heavy component decomposition naphtha that has been used as a gasoline base material in the past for a raw base material of kerosene for more detail, relating with the kerosene composition, and to provide a method of manufacturing the same.SOLUTION: The kerosene composition is obtained by mixing the heavy component decomposition naphtha with a kerosene fraction, and performing the mixture by hydrogenation processing, wherein the iodine value is at most 7, and the nitrogen concentration is at most 2 mass ppm. In addition, the method of manufacturing the kerosene composition includes a process in which the heavy component solution naphtha is mixed with the kerosene fraction, and the mixture is performed by the hydrogenation processing.

Description

  The present invention relates to a kerosene composition, and more particularly, to a kerosene composition excellent in storage stability, which uses a heavy cracked naphtha that has been conventionally used as a gasoline base material as a raw material base for kerosene, and a method for producing the same. Is.

  In recent years, due to changes in the demand structure of petroleum products, it has become a challenge to turn heavy fractions in crude oil into light petroleum products. In particular, cracking treatment technology is widely used as a technology for producing light oil from heavy oil. Among them, light oil fraction (LCO fraction) produced by fluid catalytic cracking (FCC) is converted into gasoline, light oil, and heavy oil A. The method of use is widely practiced. However, since the decomposition step is performed at a high temperature process, the hydrocarbon chain of the heavy oil is cleaved to generate an alkyl radical. For this reason, when the decomposition base material is used as a kerosene base material, there is a concern that the generated alkyl radical deteriorates the storage stability of the kerosene. In addition, the cracked base material has many olefins, sulfur, and polycyclic aromatics, and has a low cetane number, so it has been considered difficult to utilize as a kerosene base. Therefore, conventionally, it has not been common to use a decomposition base material for kerosene. However, in recent years, in order to flexibly cope with changes in the demand structure of petroleum products, it is required to apply the decomposition base material to kerosene.

  Patent Document 1 manufactures kerosene by fractionating a kerosene fraction (a fraction whose distillation range is comparable to that of ordinary kerosene) generated from fluid catalytic cracking (FCC) and hydrotreating the kerosene fraction. A method is disclosed. Patent Documents 2 and 3 describe a light fraction obtained by pyrolyzing at least one selected from specific heavy oils obtained from each device of an oil refinery plant, and an LCO fraction obtained from an FCC device. A kerosene composition containing a kerosene fraction obtained from a desulfurized and denitrogenated oil of a mixed base material containing a specific proportion of water is disclosed. Patent Document 4 contains 1 to 20% by volume of a base material composed of a fraction having a boiling point range of 190 ° C. or higher obtained by hydrocracking an LCO fraction obtained from a fluid catalytic cracking (FCC) apparatus. A kerosene composition is disclosed.

JP 2000-212579 A JP 2008-201949 A JP 2008-201950 A JP 2009-292857 A

  An object of this invention is to utilize a decomposition | disassembly type | system | group base material suitably as a kerosene base material. As the cracking base material, there are heavy cracked naphtha and light cracked light oil used as gasoline base materials. However, as described above, there is a concern that the storage stability of kerosene deteriorates when a decomposition base material is added to kerosene. Therefore, the present invention provides a kerosene composition to which a heavy cracked naphtha is added, and has a storage stability equivalent to or higher than that of a kerosene composition to which no heavy cracked naphtha is added. Objective.

  As a result of diligent investigations to solve the above problems, the inventors of the present invention mixed a heavy cracked naphtha and a kerosene fraction and hydrotreated them to achieve storage stability, in particular, color stability and oxidation stability. It has been found that an excellent kerosene composition can be provided.

  That is, the present invention relates to a kerosene composition having an iodine value of 7 or less and a nitrogen concentration of 2 mass ppm or less, obtained by mixing a heavy cracked naphtha and a kerosene fraction, and hydrotreating the mixture, and the kerosene composition. The present invention relates to a method for manufacturing a product.

  The kerosene composition of the present invention has a storage stability equivalent to or higher than that of a kerosene composition to which no heavy cracked naphtha is added. According to the production method of the present invention, a heavy cracking naphtha that is a cracking base material and is usually used as a base material for gasoline or light oil can be suitably used as a kerosene base material, and the heavy cracking is possible. A kerosene composition having a storage stability equivalent to or higher than that of a kerosene composition not containing naphtha can be provided.

Hereinafter, in the present invention,
(1) Iodine value is a value measured based on JIS K 0070 “Testing methods for acid value, saponification value, ester value, iodine value, hydroxyl value and unsaponified product of chemical products”.
(2) Nitrogen content is a value measured based on JIS K 2609 “Crude Oil and Petroleum Products—Nitrogen Content Test Method”.
(3) Sulfur content is a value measured based on JIS K2541 “Crude oil and petroleum products—Sulfur content test method”.
(4) The olefin content is a value measured based on JPI-5S-49-07 “Petroleum products—Hydrocarbon type test method—High performance liquid chromatograph method (HPLC)”.
(5) The aromatic content is a value measured based on JPI-5S-49-07 "Petroleum products-Hydrocarbon type test method-High performance liquid chromatograph method (HPLC)".
(6) Distillation properties are values measured based on JIS K 2254 “Petroleum products—Distillation test method”.
(7) Density is a value measured based on JIS K 2249 “Crude oil and petroleum products—Density test method”.
(8) The flash point is a value measured based on JIS K 2265 “Crude oil and petroleum products—flash point test method”.
(9) The smoke point is a value measured based on JIS K 2537 “Petroleum products—kerosene and aviation turbine fuel oil—smoke point test method”.
(10) Sebolt color is a value measured based on JIS K 2580 "Petroleum products-Color test method".
(11) The peroxide value is a value measured on the basis of the Petroleum Institute method JPI-5S-46-96 “Testing method for kerosene peroxide value”.

  The kerosene composition of the present invention is a kerosene composition obtained by mixing a heavy cracked naphtha and a kerosene fraction and hydrotreating the mixture, and has an iodine value of 7 or less, preferably 5 or less, and a nitrogen content. The content is 2 mass ppm or less, preferably 1 mass ppm or less. If the iodine value is not more than the above upper limit value, it is preferable because deterioration of storage stability due to heat can be prevented. Further, if the nitrogen concentration is not more than the above upper limit value, hue stability can be achieved, and deterioration of color stability due to heat can be reduced. The smaller the nitrogen content, the better, and the most preferable is 0 ppm by mass.

  The conditions for hydrotreating the mixture of the heavy cracked naphtha and the kerosene fraction may be appropriately selected according to the composition of the mixture so that the iodine value and the nitrogen content are within the above ranges. For example, the reaction tower pressure is 4 to 7 MPa, more preferably 4.7 to 6.2 MPa, further preferably 5 to 5.3 MPa, hydrogen partial pressure 4 to 6.5 MPa, more preferably 4.5 to 6 MPa, The pressure is preferably 4.6 to 5 MPa. The hydrotreatment of the mixture differs from the selective hydrodesulfurization of heavy cracked naphtha described in a later paragraph in that the hydrogen partial pressure is high. The reaction tower temperature is 200 ° C. to 400 ° C., more preferably 250 ° C. to 375 ° C., further preferably 270 ° C. to 330 ° C., and the liquid space velocity is 0.1 to 4 V / H / V, more preferably 0. 0.2 to 2 V / H / V, and the feedstock feed rate is 4 to 40 kilobarrels / day (kBD), more preferably 5 to 37 kilobarrels / day (kBD), and even more preferably 7.6 to 33 kilobarrels / day. (KBD).

  As the catalyst used for the above-mentioned hydrogenation treatment, oxides and / or sulfides of Group 6 metals and / or Group 8 to Group 10 metals of the Periodic Table of Elements are preferable. For example, one or a combination of oxides and / or sulfides such as molybdenum, tungsten, cobalt, and nickel can be used. The content of these active ingredients in the catalyst composition is in the range of 5% to 35% by weight, preferably 10% to 25% by weight as oxides and / or sulfides. The catalyst is preferably a supported catalyst, and the method for supporting the active metal component may follow a known method. The support material is preferably an inorganic oxide, such as alumina, silica, silica alumina, titania, calcium oxide, strontium oxide, barium oxide, carbon, zirconia, magnesia, and crystalline aluminosilicate, or a combination of two or more. Can be used. Among these, alumina, silica, and silica alumina are preferable. In particular, a molybdenum-based catalyst using alumina as a carrier is suitable, and cobalt or nickel may be added as a co-catalyst to improve the activity. In particular, a catalyst containing cobalt oxide and molybdenum oxide is preferred.

  Examples of the shape of the catalyst used for the above-mentioned hydrotreating include a spherical granular shape, an irregular granular shape, a cylindrical pellet shape, an extruded shape, a ring shape, and the like, but the type and size of the reaction tower, operating conditions, and economic efficiency. What is necessary is just to select suitably according to etc. The reaction tower can be used in any form such as a fixed bed, a fluidized bed or a boiling bed, but it is preferable to adopt a fixed bed from the viewpoint of the apparatus or operation. Also, a large number of two or more reaction towers can be arranged in parallel and combined for use. The shape and size of the catalyst may be selected so that the packing density in the reaction tower can be controlled. Usually, the average diameter is 0.5 mm to 5 mm, preferably 1 to 3 mm, more preferably 1 to 2 mm, and the average length is 0.5 mm to 20 mm, preferably 1 to 10 mm, more preferably 2 to 6 mm. This is preferable from the viewpoint of increasing density and suppressing pressure loss. The catalyst may be a fine powder.

  Heavy cracking naphtha blended in the kerosene composition of the present invention includes fluid catalytic cracking naphtha (FCC naphtha), coker-treated naphtha, hydrocracked naphtha, and other gasoline mixed components having a boiling range of naphtha. Naphtha and the like. Among them, FCC naphtha and coker-treated naphtha contain more olefins and are therefore preferred as a feedstock for heavy cracked naphtha. The process for producing the cracked naphtha does not particularly limit the apparatus to be used, the operating conditions, and the catalyst to be used, and a known production process may be adopted.

  As raw materials for heavy cracked naphtha, atmospheric distillation residue obtained by atmospheric distillation of crude oil, vacuum gas oil that is a distillate distillate obtained by vacuum distillation of atmospheric distillation residue, and crude oil are usually used. Pyrolysis heavy gas oil fraction obtained by pyrolysis of vacuum distillation residue oil obtained by vacuum distillation of straight distillation gas oil fraction, atmospheric distillation residue oil of distillate oil fraction obtained by pressure distillation Etc. In addition, a light cycle oil having a boiling point higher than that of the gasoline fraction obtained by the catalytic cracking process or a vacuum distillation residue fraction obtained by the hydrocracking process can be used. In particular, those obtained by hydrotreating the above-described fractions are preferable, and one fraction may be hydrotreated by itself, or two or more fractions may be mixed and hydrorefined. There may be. When using a raw material oil having a relatively low content of sulfur, nitrogen, vanadium, and nickel, it can be used without hydrotreating.

  The total olefin concentration of the heavy cracked naphtha is generally 60 wt% or less, more typically 50 wt% or less, and even 5 to 40 wt%. The heavy cracked naphtha can also have a diene concentration of 15 wt% or less, more typically 0.02 to 5 wt%. High diene concentrations are undesirable because they can result in kerosene products with poor stability and color. The sulfur content of the heavy cracked naphtha is generally 0.05 to 0.7 wt%, more typically 0.07 to 0.5 wt%. The nitrogen content of the heavy cracked naphtha is generally 5 to 500 ppm by mass, more typically 20 to 200 ppm by mass.

  In the present invention, the heavy cracked naphtha is preferably hydrodesulfurized in advance. The hydrodesulfurization of heavy cracked naphtha may be carried out by a conventionally known method, and the reaction tower can be of any type of fixed bed, fluidized bed or ebullated bed. It is preferable to adopt. Also, a large number of two or more reaction towers can be arranged in parallel and combined for use. In particular, the heavy cracked naphtha of the present invention is preferably one that has been selectively hydrodesulfurized. Selective hydrodesulfurization is a method for removing sulfur while minimizing olefin hydrogenation and octane reduction by selecting catalysts and process conditions.

For the selective hydrodesulfurization of heavy cracked naphtha, a known method may be used, for example, the SCANfining process of ExxonMobil. SCAN fining is a method that includes a single-stage and two-stage hydrodesulfurization process for hydrodesulfurizing naphtha feedstock, such as US Pat. No. 5,985,136, US Pat. No. 6,013,598. And U.S. Pat. No. 6,126,814 (the contents of the patent are incorporated herein by reference). As an embodiment of the SCAN fined, the catalyst used is from about a total weight of the catalyst based 1 wt% to about 10 wt% of MoO _3, and from about 0.1% to about 5 wt% of CoO And a Co / Mo atomic ratio of about 0.1 to about 1.0, a median pore diameter of about 60 to about 200 and a MoO ₃ surface concentration of about 0.5 × 10 ^{−4 to} 3 × 10 ⁻⁴ gMoO ₃ / m ² and an average particle size diameter of less than about 2.0 mm. For selective hydrodesulfurization, a supported catalyst may be used, and the support materials exemplified for the hydrotreatment of the above mixture can be used.

  The reaction conditions for selective hydrodesulfurization can be appropriately selected according to the desired desulfurization rate, etc., but the reaction tower temperature is usually 200 ° C. to 400 ° C., preferably 200 ° C. to 350 ° C., more preferably 250 ° C. To 330 ° C., reaction tower pressure 1 MPa to 3 MPa, preferably 1.5 to 2.6 MPa, more preferably 1.7 to 2.2 MPa, hydrogen partial pressure 0.8 MPa to 2.8 MPa, preferably 1 0.2 to 2.5 MPa, more preferably 1.35 to 2 MPa, liquid space velocity 0.1 to 4 V / H / V, preferably 0.2 to 2 V / H / V, and feedstock feed rate 5 -15 kilobarrels / day (kBD), preferably 6-14 kilobarrels / day (kBD), more preferably 6.3-13.5 kilobarrels / day (kBD).

  In the present invention, the selective hydrodesulfurized heavy cracked naphtha has an iodine value of 20 to 200, preferably 50 to 100, and a nitrogen content of 5 to 50 ppm by mass, preferably 10 to 40 ppm by mass. Yes, the amount of olefin is 15 to 40% by volume, preferably 20 to 35% by volume, and the amount of aromatic is 15 to 50% by volume, preferably 20 to 40% by volume.

  The heavy cracked naphtha is contained in an amount of 1 to 30% by volume, preferably 5 to 15% by volume, based on the total amount of the kerosene composition. If the content of heavy decomposed naphtha exceeds the upper limit, it is difficult to reduce the iodine value, which is not preferable. If the content of the heavy cracked naphtha is less than the lower limit, it becomes substantially only the kerosene fraction, and the production increase effect due to the transfer of the gasoline base material is lost, which is not preferable.

  In the present invention, the kerosene fraction is a kerosene fraction refined from crude oil and the like, and is not particularly limited. Hydrocracking produced together with straight-run kerosene obtained by atmospheric distillation of crude oil and hydrocracked light oil. Examples include kerosene and hydrorefined kerosene obtained by hydrorefining the kerosene fraction (straight kerosene, hydrocracked kerosene). In particular, it is kerosene obtained by directly distilling crude oil, and is preferably straight-run kerosene that has not been hydrotreated. The kerosene fraction usually has a boiling range of 145 to 300 ° C, a 50 vol% distillation temperature (T50) of 185 to 220 ° C, a sulfur content of 20 mass ppm or less, and particularly a sulfur content. Is preferably 10 ppm by mass or less. The olefin content is 5% by volume or less, preferably 0 to 3% by volume, and the aromatic content is 30% by volume or less, preferably 15 to 30% by volume.

  The kerosene composition of the present invention can be blended with other base materials other than the above base materials within the range not impairing the object of the present invention, but the 95% distillation temperature of kerosene may be 270 ° C. or lower. Since it is prescribed in JIS K2203, it is better that there are few heavy components. Examples of such base materials include hydrocracked light oil, light fluid catalytic cracked light oil, dewaxed desulfurized kerosene, and GTL kerosene. The blending amount of these base materials is usually 30% by volume or less, preferably 15% by volume or less, more preferably 10% by volume or less based on the total amount of the kerosene composition. In the case of a base material having a low sulfur concentration, the heavy naphtha and kerosene fraction are mixed and subjected to a hydrogenation treatment, and then mixed. In the case of a base material having a high sulfur concentration, it is preferable to perform a hydrogenation treatment after mixing the base material with a heavy naphtha and kerosene fraction. Light fluid catalytic cracking light oil corresponds to the base material having a high sulfur concentration. When mixing light fluid catalytic cracking light oil, light fluid catalytic cracking light oil is harder to desulfurize than straight-run kerosene, so it is better to carry out strict hydrotreating conditions.

  In the kerosene composition of the present invention, the olefin content is 5% by volume or less, preferably 0% by volume or more and 3% by volume or less, more preferably 0% by volume or more and 2% by volume or less. If the olefin content is less than or equal to the above upper limit, it is preferable because the deterioration of stability due to heat is small. The smaller the olefin content, the better, and 0% by volume is most preferable.

  In the kerosene composition of the present invention, the aromatic content is 30% by volume or less, preferably 15% by volume or more and 25% by volume or less, more preferably 15% by volume or more and 22% by volume or less. If the aromatic content is not more than the above upper limit value, it is possible to prevent deterioration of combustibility and reduce the risk of blowout.

  The sulfur content contained in the kerosene composition of the present invention is 20 mass ppm or less, preferably 10 mass ppm or less. If the sulfur content is less than the above upper limit, it is preferable because the odor derived from the sulfur content does not become strong. The smaller the sulfur content, the better.

  In the kerosene composition of the present invention, the Selt bolt color is preferably +25 or more, more preferably +27 or more and +30 or less. A Sebolt color of +25 or more is preferred because problems in quality and appearance, such as sludge generation due to storage deterioration, are unlikely to occur.

  In the kerosene composition of the present invention, the distillation properties are as follows: initial boiling point 140-170 ° C., preferably 145-165 ° C., 50% distillation temperature 180-220 ° C., preferably 185-215 ° C., 70% distillation temperature 195 It is -230 degreeC, Preferably it is 200-225 degreeC, 90% distillation temperature 215-260 degreeC, Preferably it is 220-250 degreeC, 95% distillation temperature 220-270 degreeC, Preferably it is 225-260 degreeC. It is preferable that the initial boiling point is lower than the above upper limit value because there is little possibility of problems such as difficulty in ignition. It is preferable that the initial boiling point is higher than the lower limit because the flash point becomes high and the possibility of falling below 40 ° C., which is the flash point standard value of kerosene determined by JISK 2203, is reduced. Further, if the 50% distillation temperature, 70% distillation temperature, 90% distillation temperature, and 95% distillation temperature are lower than the above upper limit values, there is a problem that ignition is difficult and it takes time to reach steady combustion. This is preferable because it is less likely to occur. Also, if the 50% distillation temperature, 70% distillation temperature, 90% distillation temperature, and 95% distillation temperature are higher than the above lower limit values, the flame is placed at the top of the combustion cylinder when using a core type / radial oil stove. It is preferable because it can maintain a stable combustion state in which the combustion cylinder is kept in a red-heated state without being taken out of the cylinder, and the possibility of problems such as difficulty in extinguishing the fire during the fire extinguishing is reduced.

In kerosene compositions of the present invention, the density at 15 ℃ is preferably 0.78~0.81g / cm ^3, more preferably 0.785~0.805g / cm ^3. If the density at 15 ° C. is equal to or higher than the lower limit, it is preferable because fuel efficiency can be kept good.

  In the kerosene composition of the present invention, the flash point is preferably 40 ° C. or higher, more preferably 40 to 60 ° C., still more preferably 41 to 60 ° C. A flash point of 40 ° C. or higher is preferable because flammable vapor is not generated at room temperature and the risk of ignition due to static electricity can be reduced.

  In the kerosene composition of the present invention, the smoke point is preferably 21 to 27 mm, and more preferably 23 to 27 mm. A smoke point of 21 mm or more is preferable because the combustibility is good.

  In the kerosene composition of the present invention, the peroxide value is preferably less than 5 mg / kg, more preferably 2 mg / kg, most preferably 1 mg / kg or less, due to concerns about poor combustion due to the formation of peroxide. preferable.

  A fuel oil additive can be added to the kerosene composition of the present invention as necessary. Fuel oil additives include metal deactivators such as Schiff compounds and thioamide compounds, surface ignition inhibitors such as organophosphorus compounds, detergent dispersants such as succinimides, polyalkylamines, polyetheramines, and many others. Antifreezing agents such as monohydric alcohols and ethers thereof, alkali metals and alkaline earth metal salts of organic acids, auxiliary alcohols such as sulfates of higher alcohols, anionic surfactants, cationic surfactants, amphoteric surfactants, etc. And known fuel oil additives such as rust inhibitors such as alkenyl succinates. Moreover, well-known antioxidants, such as a phenol type and an amine type, can be added to the kerosene composition of this invention to such an extent that the effect of this invention is not inhibited. The above various additives may be added singly or in combination of two or more. The addition amount of the additive can be appropriately set as long as the object of the present invention is not impaired.

  The kerosene composition of the present invention includes, for example, various petroleum stoves, petroleum fan heaters, and consumer heating devices such as petroleum water heaters, direct-fired food drying fuels, industrial fuels, and fuels for oil engines And can be preferably used in various applications such as solvent.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.

Heavy cracked naphtha The heavy cracked naphtha was selectively hydrodesulfurized. The properties of the heavy cracked naphtha were as follows.
Iodine number: 85
Nitrogen concentration: 35 mass ppm
Olefin content: 25% by volume
Aromatic content: 33% by volume
Sulfur concentration: 28 mass ppm

Kerosene fraction The kerosene fraction used straight-run kerosene. The properties of the kerosene fraction were as follows.
Boiling range: 150-270 ° C
50 vol% distillation temperature (T50): 190-210 ° C
Iodine number: 2.5
Nitrogen concentration: 1 mass ppm or less Olefin content: 1 vol% or less Aromatic content: 18 vol%
Sulfur concentration: 3 mass ppm

[Examples 1 to 3]
Manufacture of kerosene composition The heavy cracked naphtha and the kerosene fraction were mixed so that the content of heavy cracked naphtha with respect to the total amount of the kerosene composition would be the volume% shown in Table 1. Each mixture was hydrotreated under the following reaction conditions using a hydrodesulfurization apparatus.
Catalyst supported metal: molybdenum oxide-cobalt oxide / alumina Reaction tower pressure: 5.1 MPa
Hydrogen pressure: 4.8 MPa
Oil flow rate: 18.8 kilobarrels / day Reaction tower temperature: 305 ° C
Liquid space velocity: 0.9V / H / V

The properties of each kerosene composition obtained were measured. The results are shown in Table 1. The HPLC apparatus and analysis conditions used for the measurement are as follows.
Apparatus: HPLC
Model number: LC-20AD system Manufacturer: Shimadzu Corporation Mobile phase: n-hexane Pump flow rate: 1 ml / min
Column: Silver nitrate impregnated silica column, amine-modified silica column Column temperature: 40 ° C
Sample concentration: 5 vol% (diluted n-hexane)
Injection volume: 10 μl
Detector: Differential refractive index detector (RI)

[Comparative Examples 1-3]
The heavy cracked naphtha and the kerosene fraction were mixed so that the content of the heavy cracked naphtha relative to the total amount of the kerosene composition was the volume% shown in Table 1, and the properties of each mixture were measured without hydrotreating. . The results are shown in Table 1.

[Reference Example 1]
The properties of kerosene obtained by hydrotreating the kerosene fraction under the same conditions as in Examples 1 to 3 were measured. The results are shown in Table 1.

[Reference Example 2]
The properties of the kerosene fraction not hydrotreated were measured. The results are shown in Table 1.

[Color stability]
After each kerosene composition was stored at room temperature for 7 days in a light place and after 6 months storage at room temperature in a dark place, the Saybolt color was measured. The Sebolt color was measured according to JIS K2580. Moreover, oxygen was blown into each kerosene composition and heated under the temperature and pressure shown in Table 2, and the Saybolt color after the acceleration test was measured. The acceleration test was conducted using the same container and apparatus as described in JIS K 2287 (gasoline oxidation stability test method). However, the oxygen pressure was kept constant during the test by the check valve. Specifically, 100 ml of each kerosene composition was placed in a SUS container, filled with oxygen up to 500 kPa and sealed, and then immersed in an oil bath heated to each temperature shown in Table 2 for 16 hours. Then, each container was taken out from the oil bath, cooled, a sample was collected, and the Saebold color was measured.

  As shown in Table 2, the kerosene composition of Comparative Examples 1 and 2 obtained by mixing heavy cracked naphtha and kerosene fraction, and Comparative Example 3 consisting only of heavy cracked naphtha are stored for a long time, In addition, color stability decreases after the acceleration test. On the other hand, the kerosene compositions of Examples 1 to 3 that were hydrotreated after mixing the kerosene fraction and the heavy cracked naphtha exhibit excellent color stability even after long-term storage and acceleration tests.

[Peroxide value]
The peroxide value after storing each of the above kerosene compositions for 6 months in a dark place at room temperature was measured according to the Petroleum Institute method JPI-5S-46-96. Moreover, the peroxide value after performing the acceleration test by the same method as the said color stability test at the temperature of Table 3 was measured. Further, the peroxide value after each kerosene composition was stored under the conditions of ASTM D2274 (95 ° C., 16 hr, oxygen bubbling) was measured. The results are shown in Table 3.

  As shown in Table 3, the kerosene composition of the present invention has a peroxide value equivalent to that of a kerosene fraction not mixed with heavy cracked naphtha (Reference Example 1) even after long-term storage and acceleration tests. And has excellent oxidation stability.

  According to the present invention, a cracked base material that can be suitably used as a kerosene base material, which is usually used as a base material for gasoline or light oil, and a heavy cracked naphtha is added. It is possible to provide a kerosene composition having a storage stability equivalent to or higher than that of the non-kerosene composition.

Claims (7)

A kerosene composition having an iodine value of 7 or less and a nitrogen concentration of 2 mass ppm or less, obtained by mixing a heavy cracked naphtha and a kerosene fraction and hydrotreating the mixture. The kerosene composition according to claim 1, wherein the heavy cracked naphtha is preliminarily selectively hydrogenated. The kerosene composition according to claim 1 or 2, wherein the kerosene fraction is kerosene obtained by directly distilling crude oil, and is kerosene that has not been hydrotreated (direct kerosene). The kerosene composition according to any one of claims 1 to 3, comprising heavy cracked naphtha in an amount of 1 to 30% by volume. The kerosene composition according to any one of claims 1 to 4, wherein the olefin content is 5 vol% or less, the aromatic content is 30 vol% or less, and the sulfur content is 20 mass ppm or less. A method for producing a kerosene composition, comprising the steps of mixing a heavy cracked naphtha and a kerosene fraction and hydrotreating the mixture. The method for producing a kerosene composition according to claim 6, comprising a step of selectively hydrogenating the heavy cracked naphtha before mixing the heavy cracked naphtha and the kerosene fraction.