JP2010215723A - Method of manufacturing base material of gas oil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a base material of gas oil having a cetane index of at least 50 from a gas oil fraction of a synthetic crude oil manufactured from an unconventional crude oil, such as oil sand bitumen, which has been heretofore difficult in effective use as a base material of gas oil. <P>SOLUTION: The method of manufacturing the base material of gas oil includes hydrocracking the gas oil fraction containing at least 50 mass% of an aromatic component and/or an aromatic component at least a part of which is nucleus hydrogenated and having a cetane index of less than 50 to thereby convert a bicyclic naphthene in the gas oil fraction into at least a monocyclic naphthene to manufacture the base material of gas oil having a cetane index of at least 50. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a method for producing a light oil base material having a cetane index of 50 or more from a low-grade light oil fraction obtained from unconventional crude oil such as oil sand bitumen.

The light oil fraction of synthetic crude oil produced from non-conventional crude oil such as oil sand bitumen is mainly composed of polycyclic aromatics and hydrides thereof, so it has a low cetane index and is used as a light oil base. It is difficult to use.
For example, a gas oil fraction obtained from a coker pyrolysis apparatus, such as the above gas oil fraction, is mixed with straight-run gas oil in an amount of 15 to 40% by volume and then hydrotreated to have a sulfur content of 10 mass ppm or less, cetane. A technique for producing a light oil base having an index of 50 or more has been proposed (Patent Document 1). Thus, in the conventional hydrotreating technology, it was difficult to use the light oil fraction from the coker pyrolysis apparatus as a light oil base material unless it was mixed with straight-run gas oil having a high cetane index.

JP 2008-248175 A

Therefore, the mixing ratio with straight-run gas oil is also limited for diesel oil fractions in synthetic crude oil of non-conventional crude oil such as oil sand bitumen produced by a combination of coker pyrolysis equipment and hydrotreating technology. However, there is a problem that it is difficult to utilize as a light oil base material.
The present invention is a low-grade gas oil fraction having a cetane index of less than 50, such as a gas oil fraction of synthetic crude oil produced from unconventional crude oil such as oil sand bitumen, which has been difficult to use as a gas oil base until now, A method for producing a light oil base material having a cetane index of 50 or more is provided.

  The low cetane index of the light oil fraction of synthetic crude oil produced from unconventional crude oil such as oil sand bitumen is due to the fact that the gas oil fraction is a hydrogenated component of two or more polycyclic aromatics. This is because it is mainly composed, and even if the aromatic ring is completely hydrogenated by hydrogenation treatment, the hydrogenation is limited to bicyclic naphthene typified by decalin, so the cetane index only improves to about 40. . Therefore, in order to improve the cetane index to 50 or more, it is necessary to further perform a hydrocracking treatment, open the bicyclic naphthene, and convert it to a monocyclic naphthene having an alkyl group. Conversion to paraffin is preferred.

The present invention
[1] The gas oil is obtained by hydrocracking a gas oil fraction containing 50% by mass or more of an aromatic component and / or a component obtained by hydrogenating at least a part of the aromatic component and having a cetane index of less than 50, A method for producing a light oil base material, wherein a bicyclic naphthene in the fraction is converted into at least one ring naphthene to produce a light oil base material having a cetane index of 50 or more,
[2] The method for producing a light oil base material according to the above [1], comprising a step of converting the monocyclic naphthene into paraffin.
[3] The method for producing a light oil base material according to the above [1] or [2], wherein the light oil fraction is a light oil fraction obtained by distilling synthetic crude oil produced from oil sand bitumen.
[4] The method for producing a light oil base material according to the above [1] or [2], wherein the light oil fraction is a light oil fraction obtained by treating a hydrocarbon with a thermal cracking device,
[5] The catalyst used for hydrocracking of the gas oil fraction contains at least one selected from metals belonging to Group 6 and Groups 8 to 10 of the long-period periodic table, and crystalline aluminosilicate. A method for producing a light oil base material according to any one of the above [1] to [4], which is a hydrocracking catalyst

[6] The method for producing a light oil base according to the above [5], wherein the content of the crystalline aluminosilicate in the hydrocracking catalyst is 10 to 70% by mass,
[7] The method for producing a light oil base material according to the above [5] or [6], wherein the crystalline aluminosilicate is an ultrastabilized Y-type zeolite,
[8] The light oil base according to any one of the above [2] to [7], wherein the ratio of paraffin to monocyclic naphthene in the light oil base (paraffin / 1-ring naphthene) is 1.0 or less by mass ratio. Manufacturing method,
[9] The method for producing a light oil base material according to any one of the above [1] to [8], wherein the hydrocracking is performed after the gas oil fraction is hydrodesulfurized, and [10] an aromatic component. And / or a gas oil fraction having a cetane index of less than 50, containing 50% by mass or more of a component obtained by nuclear hydrogenation of at least a part of the aromatic component, according to any one of [1] to [9] above. A light oil base material having a cetane index of 50 or more obtained by a production method;
About.

According to the present invention, from a low-grade light oil fraction having a cetane index of less than 50, such as a light oil fraction of synthetic crude oil produced from unconventional crude oil such as oil sand bitumen, which has been difficult to use as a light oil base material until now. A method for producing a light oil base material having a cetane index of 50 or more can be provided.
In addition, the production method of the present invention can provide a light oil base material having a cetane index of 50 or more that can be used as a light oil base material without being mixed with straight-run light oil or the like.

[Method for producing light oil base]
The method for producing a gas oil base of the present invention comprises a gas oil fraction having a cetane index of less than 50, containing 50% by mass or more of an aromatic component and / or a component obtained by hydrogenating at least a part of the aromatic component. A gas oil base having a cetane index of 50 or more is produced by hydrocracking to convert at least one ring naphthene in the gas oil fraction into one ring naphthene.

(Diesel oil fraction with a cetane index of less than 50)
In the production method of the present invention, a gas oil fraction having a cetane index of less than 50 and containing 50% by mass or more of an aromatic component and / or a component obtained by hydrogenating at least a part of the aromatic component is used as a raw material. .
The aromatic component and the aromatic component in which at least a part of the aromatic component is nuclear hydrogenated include aromatic compounds having one or more aromatic rings, such as alkylbenzene, bicyclic or tricyclic aromatic compounds Is mentioned.

  The gas oil fraction contains a component obtained by nuclear hydrogenation of at least a part of the aromatic component. Examples of the above include the number of aromatic rings such as one ring, two rings, and three rings. Or a tetralin in which one aromatic ring out of two bicyclic aromatic rings is nuclear hydrogenated, and those containing bicyclic naphthene are effective in the effect of the present invention. It is preferable at the point obtained. The above component is obtained by nuclear hydrogenation of at least a part of the aromatic component, but finally the nuclear water is used so that the light oil fraction as a raw material contains 50% by mass or more of such component and aromatic component. What is necessary is just to be obtained. From this viewpoint and the effect of the present invention, the nuclear hydrogenation is preferably performed for 30 to 100% by volume, more preferably 50 to 100% by volume of the aromatic component. As the hydrogenation treatment method, any of the usual hydrogenation treatments used for hydrogenation of light oil fractions can be employed.

  As described above, the raw gas oil fraction contains 50% by mass or more of an aromatic component and / or a component obtained by nuclear hydrogenation of at least a part of the aromatic component, in order to exert the present invention effectively. Is preferably contained in an amount of 60% by mass or more, and more preferably 70% by mass or more. The upper limit is not particularly limited. Among the above components, the bicyclic naphthene is preferably contained in an amount of 20 to 60% by mass and more preferably 40 to 60% by mass in the light oil fraction from the same viewpoint. The bicyclic naphthene is preferably contained in the saturated content in an amount of 50 to 80% by mass, more preferably 60 to 80% by mass.

The gas oil fraction has a cetane index of less than 50. However, the present invention can sufficiently obtain the effects of the present invention for the gas oil fraction having such a cetane index. Is preferably 20-50, more preferably 35-50.
About the light oil fraction other than the light oil fraction having a cetane index of less than 50, containing 50% by mass or more of the aromatic component and / or the component obtained by nuclear hydrogenation of at least a part of the aromatic component as described above, Although it is optional to apply the production method of the present invention to this, such a light oil fraction is inherently relatively rich in paraffin and monocyclic aromatic components, and the production method of the present invention is applied. On the contrary, the decomposition thereof proceeds, and the production of the light oil base intended by the production method of the present invention may be reduced.

  In the present invention, the “light oil fraction” means a fraction having a 90% distillation temperature exceeding 267 ° C. and not more than 400 ° C. Examples of the light oil fraction that can be preferably used in the present invention include Canadian oil sands. A light oil fraction obtained by distilling synthetic crude oil produced from bitumen; a light oil fraction obtained by treating hydrocarbons with a pyrolyzer (coker) (so-called coker gas oil), especially ultra heavy oil such as Orinoco crude oil Examples include gas oil fractions obtained by pyrolyzing hydrocarbons such as crude oil in a pyrolysis apparatus. From the viewpoint of the problems and effects of the present invention, the production method of the present invention is not suitable for Canadian oil sand bitumen or the like. It can be preferably applied to a light oil fraction of synthetic crude oil produced from conventional crude oil.

The light oil fraction is not particularly limited as long as it has the above-described properties and composition as a raw material of the production method of the present invention, but generally has the following properties. . Hereinafter, the value in parentheses is a preferred range.
Pour point: -30 to -1 ° C (-20 to -10 ° C)
Density: 0.86-0.90 g / cc (0.87-0.89 g / cc)
Sulfur content: 50-1,500 mass ppm (100-1,000 mass ppm)
Distillation properties 10% distillation temperature: 250-300 ° C (270-300 ° C)
50% distillation temperature: 270-330 ° C (300-330 ° C)
90% distillation temperature: 300-400 ° C (330-380 ° C)
Saturation amount: 40 to 70% by volume (50 to 70% by volume)
Aromatic content: 30-60% by volume (30-50% by volume)
1-ring aromatic content: 20 to 40% by volume (20 to 30% by volume)
Polycyclic aromatic content: 3 to 20% by volume (5 to 15% by volume)

(Manufacture of light oil base materials with a cetane index of 50 or more)
In the production method of the present invention, a bicyclic naphthene in the raw gas oil fraction is hydrocracked to be converted into at least one cyclic naphthene to produce a light oil base material having a cetane index of 50 or more. In the present invention, “converting to at least one-ring naphthene” means that it is sufficient to have a step of converting at least two-ring naphthene to one-ring naphthene. Therefore, it may include a case where it has a step of converting 1-ring naphthene to paraffin and a case where it does not have, and can also include 1-part conversion from 1-ring naphthene to paraffin.
That is, the above-mentioned raw gas oil fraction has been sufficiently hydrogenated by hydroprocessing, and the nuclear hydrogenation of the aromatics has almost reached equilibrium, and further nuclear hydrogenation is difficult. Despite being uneconomical, its cetane index is still less than 50, which is not sufficient for use as a light oil base. In the present invention, a gas oil having a cetane index of 50 or more is obtained by further hydrogenating the bicyclic naphthene in such a raw gas oil fraction, opening the ring, converting it to a monocyclic naphthene, and opening the paraffin more preferably. A substrate could be obtained.

Ring opening of the bicyclic naphthene in the light oil fraction is performed, for example, as follows, specifically, by hydrocracking.

  The catalyst used for the ring-opening treatment is at least one selected from metals belonging to Groups 6 and 8-10 of the long-period periodic table from the viewpoint of effectively exhibiting the reactivity and the effects of the present invention. A catalyst having a seed supported on a refractory support is preferred. Of the metals belonging to Group 6 and Groups 8 to 10 of the long-period periodic table, in the present invention, from the above viewpoint, metals such as molybdenum, nickel, cobalt, and tungsten are preferable, and molybdenum, Nickel and cobalt. These can be used singly or in combination of two or more, from the viewpoint of effectively exhibiting the reactivity and the effects of the present invention.

Further, as the refractory support, those containing alumina, silica alumina, boria alumina, silica, crystalline aluminosilicate, etc. can be used. From the point of sufficiently proceeding the ring-opening reaction of bicyclic naphthene, crystalline alumino Silicate, silica alumina, and silica are preferable, and crystalline aluminosilicate is more preferable. These can be used singly or in combination of two or more.
In the present invention, as the catalyst, a hydrocracking catalyst containing at least one selected from metals belonging to Group 6 and Groups 8 to 10 of the long-period periodic table and containing crystalline aluminosilicate is provided. It can be preferably used.

The metals belonging to Groups 6 and 8 to 10 of the long periodic table are preferably contained in the catalyst in an amount of 2 to 25% by mass from the viewpoint of sufficiently proceeding with the ring-opening reaction of the bicyclic naphthene, and more Preferably it contains 5-20 mass%, More preferably, it contains 10-15 mass%.
Moreover, when using crystalline aluminosilicate, it is preferable that the content is 10-70 mass% in a catalyst from the point which advances the ring-opening reaction of bicyclic naphthene fully, More preferably, 30- It is 70 mass%, More preferably, it is 40-70 mass%.

As the crystalline aluminosilicate, Y-type zeolite, β-type zeolite, mordenite zeolite and the like can be used, but it is preferable to use super-stabilized Y-type zeolite from the viewpoint of sufficiently proceeding the ring-opening reaction of bicyclic naphthene. .
The crystalline aluminosilicate preferably has a silica / alumina (SiO ₂ / Al ₂ O ₃ ) mass ratio of 10 to 70, preferably 20 to 55, in order to effectively exhibit the present invention. Is more preferable. Further, the specific surface area, pore volume, respectively, is preferably 700~900m ² /g,0.2~0.7cc/g, respectively 800~850m ² /g,0.3~0.6cc / G is more preferable. The specific surface area can be measured by the BET method, and the pore volume can be measured by the nitrogen adsorption method.

In the present invention, in the presence of the above catalyst, a bicyclic naphthene in the gas oil fraction is opened from a raw gas oil fraction having a cetane index of less than 50 by hydrocracking, and converted into at least one ring naphthene. A light oil base material having a cetane index of 50 or more is produced. The reaction conditions at that time are as follows from the viewpoint of sufficiently proceeding with the ring-opening reaction of the bicyclic naphthene.
The hydrocracking catalyst is preferably used in an amount of 50 to 500 cc, more preferably 63 to 200 cc, based on 100 cc of the raw material oil. Moreover, it is preferable that hydrogen partial pressure is 3-10 Mpa, and it is more preferable that it is 5-7 Mpa. As the molar ratio of hydrogen is preferably 200 to 2000 nm ³ / kl, more preferably 1000 - 2000 nm ³ / kl. Furthermore, as reaction temperature, it is preferable that it is 300-400 degreeC, and it is more preferable that it is 330-380 degreeC. As the liquid hourly space velocity (LHSV), it is preferably 0.2～2.0H ^-1, and more preferably 0.5~1.6h ^-1.

In the present invention, the cetane index can be further improved by converting the monocyclic naphthene obtained in the above reaction into paraffin. However, considering the pour point of the resulting light oil base, it is preferable to moderately control the reaction from the viewpoint of low temperature fluidity. The paraffin obtained may be either n-paraffin or isoparaffin, but isoparaffin is preferred from the viewpoint of improving the cetane index.
The step of converting monocyclic naphthene to paraffin may be performed in one step, but may be performed in two or more steps. For example, by dividing the catalyst packed bed into two zones and changing the reaction conditions of each zone, in one zone (first catalyst layer), mainly two-ring naphthene is changed to one-ring naphthene and the other zone (first The two-catalyst layer can be performed mainly by converting monocyclic naphthene into paraffin.
In this case, the aforementioned hydrocracking catalyst can be used as the catalyst used in each step.

The zone on the upstream side of the feed oil feed is used as the first catalyst layer, and the reaction proceeds in a direction in which the above-mentioned purpose can be achieved by setting the hydrogen partial pressure and temperature lower than those on the downstream zone (second catalyst layer). For example, the first catalyst layer has a reaction temperature of 350 to 360 ° C., a pressure of 5 to 7 MPa, LHSV is ¹ to 5 h ⁻¹ , and the second catalyst layer has a reaction temperature of 330 to 340 ° C. (set to a lower temperature than the previous stage). , Pressure: 5-7 MPa, LHSV: 1-5 h ⁻¹ (set so that the contact time is longer than the previous stage)
The contents of bicyclic naphthene, monocyclic naphthene and paraffin in the light oil base of the present invention are 10 to 40% by mass, 20 to 50% by mass and 10 to 30% by mass, respectively, from the viewpoints of the problems and effects of the present invention. It is preferable that it is 10-30 mass%, 30-40 mass%, and 20-30 mass%, respectively.

From the above points, in the present invention, the total content of monocyclic naphthene and paraffin in the obtained light oil base material is preferably 50 to 70% by mass, and more preferably 55 to 65% by mass. preferable.
Further, the ratio of paraffin to monocyclic naphthene (paraffin / single-ring naphthene) is preferably 1.0 or less, more preferably 0.6 to 0.9, and more preferably 0.6 to 0 in terms of mass ratio. More preferably, it is .8. About the processing conditions at the time of converting 1-ring naphthene into paraffin, it exists in the range of the conditions of the said ring-opening processing of 2-ring naphthene.

The above-mentioned moderate reaction control can be performed by adjusting the conditions such as temperature, hydrogen partial pressure, hydrogen molar ratio, LHSV among the catalyst or reaction conditions. If the amount of paraffin in the oil exceeds 30% by mass and you want to reduce this somewhat, set the conditions such as temperature and hydrogen partial pressure as low as possible within the reaction progress, so It can be adjusted in the direction of reducing the amount of paraffin. If it is desired to increase the amount of paraffin in the oil after hydrocracking, the reverse process can be used.
In the present invention, a light oil base having a cetane index of 50 or more can be obtained by the production method as described above. According to the production method of the present invention, it is also possible to produce a light oil base having a cetane index of 52 or more, and further a light oil base of 54 or more, but the upper limit is about 60 from the viewpoint of maintaining low temperature fluidity. It is preferable that

In the production method of the present invention, the raw gas oil fraction is hydrocracked to convert the 2-ring naphthene in the gas oil fraction into at least 1-ring naphthene to obtain a light oil base material. It is preferable to perform a hydrodesulfurization treatment before the decomposition from the viewpoint that the bicyclic naphthene concentration can be increased.
The hydrodesulfurization treatment uses a hydrodesulfurization catalyst in the presence of hydrogen. For example, the hydrogen partial pressure is 2 to 13 MPa, the hydrogen molar ratio is 100 to 4000 Nm ³ / kl, the reaction temperature is 180 to 480 ° C., and the liquid space velocity (LHSV) It is preferable to carry out under conditions such as 0.1 to 3 h ^−1, etc., with a hydrogen partial pressure of ^{3 to} 8 Mpa, a hydrogen molar ratio of 100 to 3000 Nm ³ / kl, a reaction temperature of 300 to 380 ° C., and LHSV of 0.3 to 2 h ^−1. Is more preferable.

As the catalyst used for the hydrodesulfurization treatment, a general hydrodesulfurization catalyst can be applied. As the active metal, normally, Group 6A and Group 8 metals of the periodic table are preferably used, and examples thereof include Co—Mo, Ni—Mo, Co—W, and Ni—W. As the carrier, a porous inorganic oxide mainly composed of alumina is used. The amount used is preferably 50 to 500 cc with respect to 100 cc of the raw oil.
It is preferable that the sulfur content of the light oil base material after the said hydrodesulfurization process is 10 mass ppm or less.

[Light oil base]
The light oil base material of the present invention comprises the above-described production method, that is, a light oil having a cetane index of less than 50 and containing 50% by mass or more of an aromatic component and / or a component obtained by hydrogenating at least a part of the aromatic component. It is obtained by hydrocracking the fraction and converting the bicyclic naphthene in the gas oil fraction to at least a monocyclic naphthene.
The light oil base of the present invention has a cetane index of 50 or more, preferably 52 or more, more preferably 54 or more. Moreover, each composition is as above-mentioned.

If the light oil base material of this invention can generally be used as a light oil base material, there will be no restriction | limiting in particular in each other property, However, Generally the following properties are preferable.
That is, the pour point is preferably −20 to −7.5 ° C., more preferably −20 to −10 ° C. from the viewpoint of low temperature fluidity. Other properties are as follows. Hereinafter, the value in parentheses is a preferred range.
Density: 0.85-0.89 g / cc (0.86-0.88 g / cc)
Sulfur content: 0-10 mass ppm (0-9 mass ppm)
Distillation properties 10% distillation temperature: 250-300 ° C (270-300 ° C)
50% distillation temperature: 270-330 ° C (280-320 ° C)
90% distillation temperature: 300-360 ° C (330-350 ° C)
Saturated content: 60 to 90% by volume (75 to 90% by volume)
Aromatic content: 10-40% by volume (10-25% by volume)
1-ring aromatic content: 5 to 30% by volume (5 to 15% by volume)
Polycyclic aromatic content: 5 to 10% by volume (5 to 8% by volume)

  The light oil base material of the present invention can be used as a light oil composition by blending a lubricity improver, a cetane number improver, a detergent and the like that are usually used for light oil, if necessary. Further, the light oil base material of the present invention can be used as light oil without mixing with straight-run light oil or the like, but if necessary, other light oil fractions other than the light oil base material of the present invention, kerosene distillate. Mineral, synthetic light oil and synthetic kerosene can also be used in combination. The gas oil base of the present invention is contained in the gas oil composition in an amount of 60% by volume or more, and is preferably used, more preferably 70% by volume or more, and still more preferably 80% by volume or more.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The properties, composition and performance of the light oil fraction and the light oil base were determined according to the following method.

(1) Density Measured according to JIS K 2249.
(2) Sulfur content It measured based on JISK2541-2.
(3) Distillation property Measured according to JIS K 2254.

(4) Cetane index The cetane index was measured according to “Method for calculating cetane index using 8.4 variable equation” in JIS K 2280 “Petroleum products—fuel oil—octane number and cetane number test method and cetane index calculation method”.
(5) Pour point Measured according to JIS K 2269. In JIS, the measurement was made every 2.5 ° C., but the measurement was made every 1 ° C. to improve the test accuracy.

(6) Composition of each component Obtained by measurement according to the Petroleum Institute method JPI-5S-49-97 “Hydrocarbon type test method—high-speed chromatographic method” published by the Japan Petroleum Institute. In particular, the saturation composition was determined by using a GC × GC apparatus, model ZOEX-2006KT, manufactured by GERSTEL, with the first column: HP-5MS (30 m × 0.25 mm, film thickness: 0.25 μm), and the second column: DB-17 (2.0 m × 0.1 mm, film thickness: 0.1 μm), oven temperature: 50 ° C. (0 min) → (temperature rise: 3 ° C./min)→280° C. (10 min hold), inlet And the detector temperature: 280 ° C., injection amount: 0.1 μL, qualitatively performed by MS, and quantified by FID.

[Preparation of catalyst A (hydrodesulfurization catalyst)]
The hydrodesulfurization catalyst was prepared by impregnating and supporting a metal solution containing nickel, molybdenum and phosphorus on an alumina support as follows.
95 g of basic nickel carbonate (FLUKA: NiO ₂ ; 62.3 mass%), 323 g of molybdenum trioxide and 39 g of normal phosphoric acid (purity 80 mass%) are added to 1000 cc of ion-exchanged water, and dissolved at 80 ° C. with stirring. After concentration at 80 ° C., the mixture was cooled to room temperature and adjusted to 500 cc with pure water to prepare a nickel molybdenum phosphorus impregnating solution (S1).
To 100 g of γ-alumina carrier (A1) having a water absorption rate of 0.8 cc / g, 60 cc of hydroxycarboxylatotitanium ammonium solution (T1) was diluted with pure water so as to match the amount of water absorption, and impregnated at normal pressure. After drying in vacuum at 1 ° C. for 1 hour, drying in a dryer at 120 ° C. for 3 hours and firing at 500 ° C. for 4 hours gave a carrier (A2).
50 cc of nickel-molybdenum phosphorus impregnation liquid (S1) was sampled, 6 g of triethylene glycol was added, and 100 g of carrier (A2) having a water absorption rate of 0.75 cc / g was adjusted with pure water to match the water absorption rate. The solution was impregnated under normal pressure and dried at 120 ° C. for 16 hours to prepare Catalyst A (hydrodesulfurization catalyst).

[Preparation of catalyst B (hydrocracking catalyst)]
The naphthene ring-opening catalyst was prepared by impregnating and supporting a metal solution containing nickel / molybdenum on an alumina carrier as follows.
Synthetic Na—Y zeolite (Na ₂ O content: 13.3 mass%, SiO ₂ / Al ₂ O ₃ molar ratio: 5.0) was subjected to ammonium ion exchange, and NH ₄ —Y zeolite Na ₂ O content: 1. 3% by mass) was obtained. This was steamed at 580 ° C. to obtain a steamed zeolite. After 10 kg of steamed zeolite was suspended in 115 liters of pure water, the suspension was heated to 75 ° C. and stirred for 30 minutes. Next, 63.7 kg of 10 mass% sulfuric acid solution was added to this suspension over 35 minutes, and 11.5 kg of ferric sulfate solution having a concentration of 0.57 mol / l was added over 10 minutes. After stirring, filtration and washing were performed to obtain an iron-containing crystalline aluminosilicate slurry I having a solid content concentration of 30.5% by mass. A portion of this iron-containing crystalline aluminosilicate slurry I was taken and dried, and then the pore structure was measured. As the pore structure, the pore volume of 600 Å or less is 0.5393 cc / g, the proportion of the pore volume of 50 to 300 に in the pore volume of 600 Å or less is 22.8%, and the pore volume of 100 to 300 Å The volume ratio was 15.6%.

Next, the alumina slurry was adjusted. 80 kg of sodium aluminate solution (concentration of Al ₂ O ₃ : 5.0% by mass) and 240 g of 50% by mass of gluconic acid solution were placed in a stainless steel container with a steam jacket having an internal volume of 200 liters and heated to 60 ° C. Next, 88 kg of aluminum sulfate solution (concentration of Al ₂ O ₃ : 2.5% by mass) is prepared in a separate container, this diluted aluminum sulfate solution is added so that the pH becomes 7.2 in 15 minutes, and an aluminum hydroxide slurry ( Preparation slurry I) was obtained.
The blended slurry I was further aged for 60 minutes while maintaining the temperature at 60 ° C. Next, the total amount of the prepared slurry was dehydrated with a flat plate filter and washed with 600 liters of 0.3% by mass ammonia water at 60 ° C. to obtain an alumina cake. A part of this alumina cake was used pure water and 15% by mass of ammonia water to obtain a slurry having an alumina concentration of 12.0% by mass and a pH of 0.5. This slurry was placed in a stainless steel aging tank equipped with a refluxer and aged at 95 ° C. for 8 hours with stirring. Next, pure water was added to the aging slurry, diluted to an alumina concentration of 9.0% by mass, transferred to an autoclave equipped with a stirrer, and aged at 145 ° C. for 5 hours. Further, the mixture was heated and concentrated so that the concentration in terms of Al ₂ O ₃ was 20% by mass, and deammoniated at the same time to obtain alumina slurry A.

The catalyst was prepared by adding 3200 g of iron-containing crystalline aluminosilicate slurry I (30.5 mass% concentration) and 2625 g of alumina slurry A (20 mass% concentration) to a kneader and extruding while heating and stirring. And then extruded into a 1 / 16-inch size trilobal pellet. Subsequently, after drying at 110 degreeC for 16 hours, it baked at 550 degreeC for 3 hours, and obtained the support | carrier A3 of 50/50 by iron containing crystalline aluminosilicate / alumina (solid content conversion mass ratio).
Next, a suspension of molybdenum trioxide and nickel carbonate in pure water was heated to 90 ° C., and then malic acid was added and dissolved. The solution A3 was impregnated on the carrier A3 so that the total amount of the catalyst was 10.0% by mass as MoO _{3 and} 4.25% by mass as NiO, dried, calcined at 550 ° C. for 3 hours, and the catalyst B ( Hydrocracking catalyst) was obtained. In the obtained catalyst B, the molybdenum content was 6.7% by mass, the nickel content was 3.3% by mass, and the crystalline aluminosilicate content was 50% by mass. Further, the obtained catalyst B had a specific surface area of 455 m ² / g, a pore volume of 0.62 cc / g, and a pore volume of 1000 mm or more in pore diameter of 0.13 cc / g.
The specific surface area was measured by the BET method, the pore volume, and the pore distribution were measured by the mercury intrusion method.

Comparative Example 1
A catalyst A was used in an amount of 83 cc with respect to 100 cc of raw material oil, and reacted in the presence of 0.83 hours under the following reaction conditions, and a synthetic crude oil produced from an oil sand bitumen having the composition and properties shown in Table 1 below. The gas oil fraction was desulfurized to a sulfur content of 10 mass ppm or less. Table 1 shows the properties and composition of the obtained light oil base.
Hydrogen partial pressure: 7 MPa
Hydrogen molar ratio: 2000 Nm ³ / kl
Reaction temperature: 345 ° C
LHSV: 1.2h ^-1

Example 1
The light oil base material obtained in Comparative Example 1 was reacted for 0.83 hours under the following reaction conditions in the presence of 83 cc of Catalyst B with respect to 100 cc to obtain a light oil base material with improved cetane index. Table 1 shows the properties and composition of the obtained light oil base.
Hydrogen partial pressure: 7 MPa
Hydrogen molar ratio: 2000 Nm ³ / kl
Reaction temperature: 355 ° C
LHSV: 1.2h ^-1

Example 2
A light oil base material having an improved cetane index was obtained by reacting 100 cc of the light oil base material obtained in Comparative Example 1 in the presence of 83 cc of catalyst B under the following reaction conditions for 0.83 hours. Table 1 shows the properties and composition of the obtained light oil base.
Hydrogen partial pressure: 5 MPa
Hydrogen molar ratio: 2000 Nm ³ / kl
Reaction temperature: 355 ° C
LHSV: 1.2h ^-1

  From Table 1, in the hydrogenation treatment of Comparative Example 1, only a slight hydrogenation of the bicyclic aromatic and tricyclic aromatics occurs and the cetane index is hardly improved. On the other hand, in Example 1, naphthene ring opening occurred and the saturation content increased. As a result, the cetane index improved to 56. Further, the pour point maintained a high low temperature fluidity of −13 ° C. Further, in Example 2, the hydrogen partial pressure was set to be close to that of the existing light oil ultra-deep desulfurization apparatus, but the catalyst performance was still sufficiently exhibited and the cetane index was improved to 54. Further, as in Example 1, the pour point maintained a low temperature fluidity of −15 ° C.

  According to the production method of the present invention, the cetane index of a light oil fraction of synthetic crude oil produced from unconventional crude oil such as oil sand bitumen, which has been difficult to use as a light oil base material, is 50 or more. Since it can do, the obtained light oil fraction can be used conveniently as a light oil base material.

Claims (10)

  Hydrocracking a gas oil fraction having a cetane index of less than 50 containing 50% by mass or more of an aromatic component and / or a component obtained by nuclear hydrogenation of at least a part of the aromatic component, in the gas oil fraction A method for producing a light oil base material, wherein the dicyclic naphthene is converted into at least one ring naphthene to produce a light oil base material having a cetane index of 50 or more.   The manufacturing method of the light oil base material of Claim 1 including the process of converting the said 1-ring naphthene into a paraffin.   The method for producing a light oil base material according to claim 1 or 2, wherein the light oil fraction is a light oil fraction obtained by distilling synthetic crude oil produced from oil sand bitumen.   The manufacturing method of the light oil base material of Claim 1 or 2 whose said light oil fraction is a light oil fraction obtained by processing a hydrocarbon with a thermal cracking apparatus.   A hydrogenation in which the catalyst used for hydrocracking of the light oil fraction contains at least one selected from metals belonging to Group 6 and Groups 8 to 10 of the long-period periodic table, and crystalline aluminosilicate The manufacturing method of the light oil base material in any one of Claims 1-4 which is a cracking catalyst.   The manufacturing method of the light oil base material of Claim 5 whose content of the crystalline aluminosilicate in the said hydrocracking catalyst is 10-70 mass%.   The method for producing a light oil base material according to claim 5 or 6, wherein the crystalline aluminosilicate is ultra-stabilized Y-type zeolite.   The manufacturing method of the light oil base material in any one of Claims 2-7 which makes the ratio (paraffin / 1-ring naphthene) with respect to monocyclic naphthene of the paraffin in a light oil base material 1.0 or less by mass ratio.   The method for producing a light oil base material according to any one of claims 1 to 8, wherein the hydrocracking is performed after hydrodesulfurization treatment of the light oil fraction.   A gas oil fraction having a cetane index of less than 50, comprising 50% by mass or more of an aromatic component and / or a component obtained by nuclear hydrogenation of at least a part of the aromatic component, according to any one of claims 1 to 9. A light oil base material having a cetane index of 50 or more obtained by a production method.