JP2006233087A - Kerosene composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-sulfur kerosene composition exhibiting improved oxidation stability in itself without requiring addition of an antioxidant. <P>SOLUTION: The kerosene composition has distillation properties of an initial boiling point of 135-170°C, a 50% distillation point of 165-220°C, a 70% distillation point of 170-240°C, a 90% distillation point of 215-265°C and a 95% distillation point of 230-270°C, and a composition of a sulfur content of at most 50 mass ppm, an aromatic content of at most 25 vol% with a bicyclic aromatic content of at most 2.5 vol% and a tricyclic or higher cyclic aromatic content of at most 0.5 vol%, and has an oxidation stability index Y represented by a certain formula of at most 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a kerosene composition, particularly a kerosene composition used for petroleum stoves, and more particularly to a low-sulfur kerosene composition having excellent oxidation stability.

  The types and standards of kerosene currently used in oil stoves are shown in the Japanese Industrial Standard (JIS K2203), and among these, No. 1 kerosene is widely used for household heating equipment and the like. The kerosene fraction is mainly obtained by fractionating crude oil by atmospheric distillation so as to have a predetermined distillation property. In general, the hydrodesulfurization unit is then hydrorefined so that the sulfur content becomes a predetermined amount or less, and further, in the kerosene production process, the light component is evaporated by a stripper so that the flash point becomes 40 ° C. or higher. Adjusted.

The quality of kerosene obtained in this way is managed based on the standard shown in JIS K2203 as described above. However, in practical use, oxidation stability is stable without deterioration for a long time as quality outside the standard. It is important from the viewpoint of storing (stocking). And the technique of adding antioxidant is known as a method of improving the oxidation stability of kerosene (for example, refer to patent documents 1 and patent documents 2). However, this technique relies on the action of the antioxidant, and it is desired to improve the oxidation stability of the kerosene itself. There are also proposals regarding techniques for improving the odor and combustibility of kerosene (see, for example, Patent Document 3 and Patent Document 4), but this proposal has not improved the oxidation stability of kerosene itself.
In recent years, low sulfur kerosene with low environmental impact has been demanded from the viewpoint of environmental conservation.

JP 2004-182744 A JP 2004-182745 A Japanese Patent Publication No.7-103384 Japanese Patent Laid-Open No. 3-182594

  An object of the present invention is to provide a low-sulfur kerosene composition in which the oxidation stability of the kerosene composition itself is improved in view of the above-described conventional situation.

As a result of intensive studies to achieve the above object, the present inventor has found that a specific component contained in kerosene greatly affects the oxidation stability of kerosene, and made kerosene by optimizing the composition. The present invention has been completed by obtaining the knowledge that the oxidation stability of itself can be improved.
That is, in order to achieve the above object, the present invention has an initial boiling point of 135 to 170 ° C, a 50% distillation temperature of 165 to 220 ° C, a 70% distillation temperature of 170 to 240 ° C, and a 90% distillation temperature of 215 to 265. C., 95% distillation temperature of 230 to 270.degree. C., sulfur content is 50 mass ppm or less, aromatic content is 25 volume% or less, of which bicyclic aromatic content Has a composition in which the content of aromatics in three or more rings is 0.5% by volume or less, and the oxidation stability index Y represented by the following formula (I) is 10 or less. The kerosene composition characterized by the above is provided.
Y = 1.63 × [Naphthenebenzene content (volume%)] + 0.30 × [Bicyclic naphthenes content (volume%)]
-0.57 x [Naphthalene content (% by volume)] Formula (I)

  The kerosene composition of the present invention has excellent oxidation stability, for example, when it is stored in a plastic tank for one year, it does not generate peroxide, can be stored stably without deterioration for a long time, and has low sulfur. And practically useful.

Hereinafter, the present invention will be described in detail.
The distillation properties of the kerosene composition in the present invention are as follows: initial boiling point 135-170 ° C., 50% distillation temperature 165-220 ° C., 70% distillation temperature 170-240 ° C., 90% distillation temperature 215-265 ° C., 95 % Distillation temperature of 230 to 270 ° C., preferably initial distillation point of 140 to 165 ° C., 50% distillation temperature of 170 to 220 ° C., 70% distillation temperature of 175 to 240 ° C., 90% distillation temperature of 215 to 260 And a 95% distillation temperature of 235 to 270 ° C. When the initial boiling point is within 170 ° C., the ignitability is excellent. When the initial boiling point is 135 ° C. or higher, the flash point can be kept high, and there is little possibility of falling below 40 ° C., which is the flash point standard value of kerosene defined in JIS K2203. Also, if the 50% distillation temperature is within 220 ° C, the 70% distillation temperature is within 240 ° C, the 90% distillation temperature is within 265 ° C, and the 95% distillation temperature is within 270 ° C, it is easy to ignite, so that it is steady. It takes no time to reach combustion. If the 50% distillation temperature is 165 ° C or higher, the 70% distillation temperature is 170 ° C or higher, the 90% distillation temperature is 215 ° C or higher, and the 95% distillation temperature is 230 ° C or higher, the core type / radial type When using an oil stove, it is possible to maintain a stable combustion state in which the combustion cylinder is kept in a red-heated state without emitting a flame from the upper part of the combustion cylinder, and it is easy to extinguish the fire.
In the present invention, the distillation property is measured by the atmospheric pressure distillation test of JIS K2254.

The sulfur content contained in the kerosene composition in the present invention is 50 mass ppm or less, preferably 10 mass ppm or less. By setting the sulfur content to 50 mass ppm or less, the odor or the like derived from the sulfur content can be reduced.
In the present invention, the sulfur content is measured by a microcoulometric titration method according to JIS K2541.

The composition of the kerosene composition in the present invention has an aromatic content of 25% by volume or less, preferably 20% by volume or less. By setting the aromatic content within 25% by volume, there is little possibility of causing poor flammability due to high smoke point and generation of soot.
In addition, in this invention, the content rate (composition rate) of aromatic content is calculated | required based on JPI-5S-49-97 "petroleum product-hydrocarbon type test method-high performance liquid chromatograph method (HPLC)".

The kerosene composition of the present invention has a bicyclic aromatic content of 2.5% by volume or less, preferably 2.3% by volume or less, and a tricyclic or higher aromatic content of 25% by volume of the aromatic content. Is 0.5 volume% or less, preferably 0.3 volume% or less. If the bicyclic aromatic content is 2.5 vol% or less, and the tricyclic or higher aromatic content is less than 0.5 vol%, the odor is weak and the flammability is good. Is less likely to lead to
In addition, in this invention, the content rate of a 2 ring aromatic component and a 3 or more ring aromatic content is calculated | required based on JPI-5S-49-97.

  Furthermore, the kerosene composition in the present invention has an oxidation stability index Y represented by the above formula (I) of 10 or less, preferably 5 or less. This oxidation stability index Y indicates the degree of oxygen consumption in the oxidation reaction of the kerosene composition, and each coefficient in the above formula (I) represents each of naphthenebenzenes, bicyclic naphthenes, and naphthalenes. It is a value calculated from oxidation stability. The values of these coefficients show that naphthenebenzenes greatly affect the oxidative stability of kerosene compositions, and bicyclic naphthenes have a lesser effect on the oxidative stability of kerosene compositions than naphthenebenzenes. Naphthalenes have been shown to contribute to improving the oxidation stability of kerosene compositions. By preventing the oxidation stability index Y from exceeding 10, the oxidation stability is excellent and, for example, generation of peroxide can be suppressed even when stored in a polytank for one year.

In the present invention, the content ratio of the bicyclic naphthenes is determined by gas chromatographic method-mass after the fuel oil composition is fractionated into an aromatic component and a saturated component by high performance liquid chromatography (HPLC). Analyzed by analysis method (GC-MS), analyzed according to ASTM D 2786, and calculated the ratio of bicyclic naphthenes in the saturated content, and the ratio obtained here was calculated according to JPI-5S-49-97 “Petroleum products—Carbonization”. It is determined by multiplying the saturation fraction determined by “Hydrogen Type Test Method—High Performance Liquid Chromatograph Method”.
The content of naphthenebenzenes and naphthalenes is analyzed according to ASTM D 3239 by analyzing the aromatic fraction fractionated by high performance liquid chromatography (HPLC) by gas chromatography-mass spectrometry (GC-MS). The ratio of naphthenebenzenes and the ratio of naphthalenes in the aromatic content is calculated, and the ratio obtained here is calculated by multiplying the aromatic content ratio determined by JPI-5S-49-97.
The bicyclic naphthenes referred to here are decalin and alkyl substituent derivatives of decalin. In addition, naphthenebenzenes indicate tetralin and its alkyl substituent derivatives, indane and its alkyl substituent derivatives, and the like, and naphthalenes indicate naphthalene and its alkyl substituent derivatives and the like.

  The method for producing the kerosene composition in the present invention is not particularly limited and can be carried out by various production methods. Various raw materials can be mixed, or various raw materials can be purified so as to have the properties defined in the present invention. Can be obtained. For example, a kerosene fraction obtained by atmospheric distillation of crude oil or a desulfurized kerosene obtained by desulfurizing them can be used for the production of the kerosene composition of the present invention. Furthermore, a direct desulfurized kerosene fraction obtained from a direct desulfurization apparatus, a kerosene fraction obtained by hydrocracking heavy oil or residual oil, and the like can be used, and production raw materials are not particularly limited.

  Moreover, in the kerosene composition of this invention, various fuel oil additives can be added suitably as needed. Examples of the fuel oil additive include metal deactivators such as Schiff type compounds and thioamide type compounds, surface ignition preventives such as organophosphorus compounds, detergent dispersants such as succinimide, polyalkylamine, and polyetheramine. Anti-icing 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, cationic surfactants, amphoteric surfactants And known fuel oil additives such as antistatic agents such as alkenyl succinate and the like. 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 can be added singly or in combination. Moreover, the addition amount of these additives can be suitably set as needed.

  The kerosene composition of the present invention can be preferably used for so-called consumer heaters, such as various petroleum stoves, petroleum fan heaters, or oil-type water heaters. It can be preferably used in various applications such as fuel for fuel, fuel for oil engines, and solvent.

  Next, the present invention will be described more specifically with reference to examples and comparative examples. In addition, this invention is not restrict | limited at all by these examples.

In the following examples and comparative examples, the flash point, distillation properties, sulfur content, and smoke point were measured according to the method defined in JIS K2203.
In the storage test, a 3 L sample was placed in a 10 L red plastic tank and stored indoors at room temperature for one year. Moreover, the peroxide measurement after a storage test was performed based on JPI-5S-46-96.
The ratio of the saturated component, the aromatic component, and the aromatic component according to the number of rings were measured based on JPI-5S-49-97. The apparatus configuration and analysis conditions of HPLC are shown below.
Equipment: Agilent 1100 Series (ALS: G1329A, Bin Pump: G1312A, Degasser: G1379A, Rid: G1362A, Colcom: G1316A)
Mobile phase: n-hexane Flow rate: 1.0 ml / min
Column: Silver nitrate impregnated silica column (4.6mml.D. * 70mmL. Senshu Scientific AgNO3-1071-Y): Amine modified column (4.0mml.D. * 250mmL. 2 Senshu Scientific LICHROSORB-NH2)
Column temperature: 35 ° C
Sample concentration: 10 vol%
Injection volume: 5 μl

Moreover, the type analysis of the saturated content and the aromatic content was performed by the following method.
First, after fractionating the sample into a saturated component and an aromatic component by HPLC, type analysis was performed on each of the saturated component and the aromatic component by GC-MS. Based on the analysis results obtained here, the saturation content was analyzed according to ASTM D 2786, the aromatic content was analyzed according to ASTM D 3239, the naphthene ratio in the saturation content and the naphthene ratio by number of rings, and the aromatic content. The ratio of naphthenebenzenes and naphthalenes was determined. The analysis conditions are shown below.
Apparatus: HP-6890 HP5973 Quadrupole mass spectrometer Column: DB-1: 30 m × 0.25 mm I.D. D. × 0.25μm
Oven temperature: 40 ° C. (1 min) → 10 ° C./min→280° C. (5 min)
Inlet temperature: 43 ° C
Interface temperature: 300 ° C
Carrier gas: He: 55KPa Constant flow mode ON
Solvent Delay: 4.5min
Mass range: 50-500 Threshold = 100 Sampling # 3
Ionization voltage: 70 eV
Injection method: On-column injection 3.0 μl (aromatic content), 1.0 μl (saturated content)

<Example 1>
A boiling kerosene fraction having a boiling range of 149 to 271 ° C. and a sulfur content of 0.19% by mass obtained by atmospheric distillation of crude oil, a reaction temperature (WABT) of 320 ° C., a hydrogen partial pressure of 4.5 MPa, a liquid space A kerosene composition having a boiling point range of 149 to 269 ° C. and a sulfur content of 9 mass ppm was obtained by desulfurization treatment under conditions of a speed (LHSV) of 5.2 h ⁻¹ . Table 1 shows the properties of the obtained kerosene composition and the storage test results.

<Example 2>
A boiling kerosene fraction having a boiling point range of 149 to 271 ° C. and a sulfur content of 0.19% by mass obtained by subjecting crude oil to atmospheric distillation was reacted at a reaction temperature (WABT) of 328 ° C., a hydrogen partial pressure of 4.5 MPa, and a liquid space. A kerosene composition having a boiling point range of 145 to 265 ° C. and a sulfur content of 4 mass ppm was obtained by desulfurization treatment under conditions of a speed (LHSV) of 5.2 h ⁻¹ . Table 1 shows the properties of the obtained kerosene composition and the storage test results.

<Example 3>
A straight-run kerosene fraction having a boiling point range of 140 to 278 ° C. and a sulfur content of 0.23% by mass obtained by atmospheric distillation of crude oil is converted to a reaction temperature (WABT) of 295 ° C., a hydrogen partial pressure of 4.3 MPa, and a liquid space. A kerosene composition having a boiling point range of 149 to 274 ° C. and a sulfur content of 4 mass ppm was obtained by desulfurization treatment under conditions of a speed (LHSV) of 1.3 h ⁻¹ . Table 1 shows the properties of the obtained kerosene composition and the storage test results.

<Example 4>
1. 15% by volume of n-paraffin solvent adjusted to have a boiling range of 145 to 258 ° C. using a commercially available n-paraffin solvent (n-C8 to n-C15) having a purity of 98.0% by volume or more; 1. 11.5% by volume of a commercially available isoparaffin solvent having a boiling point range of 166 to 219 ° C. and a purity of 98.0% by volume or more; 3. 3.5% by volume of a commercially available isoparaffin solvent having a boiling point range of 202 to 262 ° C. and a purity of 98.0% by volume or more; 4. 35.0% by volume of a commercially available naphthenic solvent having a boiling point range of 157 to 179 ° C. and a purity of 99.0% by volume or more; 5. 5.0% by volume of a commercially available naphthenic solvent having a boiling point range of 201 to 217 ° C. and a purity of 99.0% by volume or more; 6. 10.0% by volume of a commercially available naphthenic solvent having a boiling point range of 221 to 240 ° C. and a purity of 99.0% by volume or more; 7. 17.5% by volume of a commercially available aromatic solvent having a boiling point range of 160 to 180 ° C. and a purity of 99.0% by volume or more; A kerosene composition having a boiling range of 162 to 253 ° C. and a sulfur content of 1 mass ppm was obtained by mixing 2.5 vol% of commercially available special grade naphthalene. Table 1 shows the properties and storage test results of the kerosene composition obtained.

Comparative Example 1
A straight-run kerosene fraction having a boiling point range of 139 to 289 ° C. and a sulfur content of 0.29% by mass obtained by atmospheric distillation of crude oil, reaction temperature (WABT) 315 ° C., hydrogen partial pressure 5.5 MPa, liquid space A kerosene composition having a boiling point range of 146 to 291 ° C. and a sulfur content of 5 mass ppm was obtained by desulfurization treatment under conditions of a rate (LHSV) of 3.0 h ⁻¹ . Table 2 shows the properties of the obtained kerosene composition and the storage test results.

Comparative Example 2
1. 15% by volume of n-paraffin solvent adjusted to have a boiling range of 145 to 258 ° C. using a commercially available n-paraffin solvent (n-C8 to n-C15) having a purity of 98.0% by volume or more; 1. 11.5% by volume of a commercially available isoparaffin solvent having a boiling point range of 166 to 219 ° C. and a purity of 98.0% by volume or more; 3. 3.5% by volume of a commercially available isoparaffin solvent having a boiling point range of 202 to 262 ° C. and a purity of 98.0% by volume or more; 4. 35.0% by volume of a commercially available naphthenic solvent having a boiling point range of 157 to 179 ° C. and a purity of 99.0% by volume or more; 5. 5.0% by volume of a commercially available naphthenic solvent having a boiling point range of 201 to 217 ° C. and a purity of 99.0% by volume or more; 6. 10.0% by volume of a commercially available naphthenic solvent having a boiling point range of 221 to 240 ° C. and a purity of 99.0% by volume or more; 7. 12.0% by volume of a commercially available aromatic solvent having a boiling point range of 180 to 209 ° C. and a purity of 99.0% by volume or more; A kerosene composition having a boiling point range of 164 to 245 ° C. and a sulfur content of 1 mass ppm was obtained by mixing 8.0 vol% of commercially available special grade tetralin. Table 2 shows the properties of the obtained kerosene composition and the storage test results.

  As shown in Tables 1 and 2 above, Comparative Example 1 having a relatively high content of naphthenes, particularly bicyclic naphthene, and Comparative Example 2 having a relatively high content of naphthenebenzenes each have an oxidation stability index Y. It was beyond the range specified in the present invention, and peroxide was generated when stored in a plastic tank for 1 year. On the other hand, Examples 1 to 4 in which the oxidation stability index Y falls within the range defined by the present invention are all excellent in oxidation stability, and no peroxide was generated when stored in a plastic tank for 1 year.

Claims (1)

Distillation properties of initial boiling point 135-170 ° C, 50% distillation temperature 165-220 ° C, 70% distillation temperature 170-240 ° C, 90% distillation temperature 215-265 ° C, 95% distillation temperature 230-270 ° C The sulfur content is 50 mass ppm or less, the aromatic content is 25% by volume or less, of which the bicyclic aromatic content is 2.5% by volume or less, the tricyclic or higher aromatic content A kerosene composition having a composition having a content of 0.5% by volume or less and an oxidation stability index Y represented by the following formula (I) of 10 or less.
Y = 1.63 × [Naphthenebenzene content (volume%)] + 0.30 × [Bicyclic naphthenes content (volume%)]
-0.57 x [Naphthalene content (% by volume)] Formula (I)