JP2011202000A - Method for hydrorefining kerosene fraction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a kerosene base material having a high smoke point in a good yield from a kerosene fraction having a low smoke point by hydrorefining.SOLUTION: This method for hydrorefining the kerosene fraction is provided by using the kerosene fraction containing ≥90 mass% fraction of a 140 to 280°C boiling point range, a ≥8 mass% naphthene-based hydrocarbon having ≥2 rings and a ≥18 mass% aromatic hydrocarbon, and hydrorefining at a fixed bed reaction device filled with a solid acid catalyst without containing a zeolite loaded with a metal of the group 6 of the periodic table and a catalyst containing a USY zeolite loaded with the metal of the group 6 of the periodic table and having a ≤0.5 μm mean particle diameter.

Description

  The present invention relates to a hydrorefining method for improving the smoke point of a produced oil while removing sulfur in a kerosene fraction in the presence of hydrogen and obtaining a kerosene base material with high yield.

  In recent years, the demand for environmentally friendly clean liquid fuels has increased rapidly. For example, when focusing on the quality of kerosene, it is necessary to make the sulfur content 80 ppm or less (JIS No. 1 kerosene) and the smoke point 23 mm or more. For this reason, oil companies have taken a system to produce clean fuel by improving the catalyst and adding equipment.

Kerosene fuel supplied to consumers is mainly made of hydrodesulfurized straight-run kerosene.
In general, the hydrorefining of kerosene and light oil is carried out under high-temperature and high-pressure reaction conditions in a hydrogen stream by filling a fixed-bed reaction tower with a desulfurization catalyst. As the desulfurization catalyst, a catalyst in which alumina is used as a carrier and active metals such as molybdenum and cobalt are supported thereon is often used. The desulfurization activity at this time is greatly influenced by the type or preparation method of the support, the type of active metal, and the amount supported. For example, Non-Patent Document 1 discloses the effect on the desulfurization activity of a support other than alumina. There is also a report that hydrogenation activity is greatly improved by using an amorphous solid acid as a carrier (Non-patent Document 2).

The above-mentioned hydrorefining is a treatment method centering on middle distillate obtained by fractionating from petroleum, but considering future oil depletion, bitumen reformed oil derived from oil sands, synthetic crude oil, etc. Hydrorefining of the kerosene fraction corresponding to the treatment is important.
Compared with the kerosene fraction from petroleum, the kerosene fraction derived from oil sand has a very low smoke point due to the presence of two or more naphthenic hydrocarbons and aromatic hydrocarbons. Therefore, in the hydrorefining of the kerosene fraction derived from the oil sand, it is necessary not only to desulfurize but also to improve the smoke point.

Applied Catalysis A: General 257 (2004) 157-164 (Elsevier) Journal of Catalysis 252 (2007) 321-334 (Elsevier)

Conventional kerosene hydrorefining catalysts have been developed to treat kerosene fractions fractionated from crude oil, so two or more naphthenic hydrocarbons fractionated from synthetic oils derived from oil sands, etc. It cannot cope with a kerosene fraction with a low smoke point that contains a large amount of aromatic hydrocarbons.
In order to improve the smoke point of such a kerosene fraction, naphthene ring opening is indispensable. For this purpose, an amorphous solid acid or zeolite having acid properties can be used as a catalyst.
However, although the zeolite catalyst opens naphthene, the kerosene fraction is lightened to produce a naphtha fraction because of its high cracking activity, resulting in a decrease in the yield of the resulting kerosene base material. It has been avoided.
The object of the present invention is not limited to crude oil, but has a low smoke point for kerosene fractions having a low smoke point containing a large amount of two or more naphthenic hydrocarbons and aromatic hydrocarbons, such as synthetic crude oil derived from oil sands. An object of the present invention is to provide a hydrorefining method for obtaining an improved kerosene base material with high yield.

As a result of intensive studies, the inventors of the present invention have a zeolite-free catalyst and an average particle size of 0.5 μm for a raw kerosene fraction having a low smoke point and containing a large amount of two or more naphthenic hydrocarbons and aromatic hydrocarbons. It has been found that lightening can be suppressed and the smoke point of the product oil can be improved by hydrorefining in combination with a catalyst containing the following microcrystalline USY zeolite, and the present invention has been completed.
That is, the present invention is a kerosene fraction containing 90% by mass or more of a fraction having a boiling range of 140 to 280 ° C., containing 8% by mass or more of bicyclic or more naphthenic hydrocarbons and 18% by mass or more of aromatic hydrocarbons. And a solid acid catalyst containing no zeolite carrying a metal of group 6 of the periodic table and a catalyst containing USY zeolite having an average particle diameter of 0.5 μm or less and carrying a metal of group 6 of the periodic table The present invention relates to a hydrorefining method for a kerosene fraction, characterized by hydrotreating in a packed fixed bed reactor.

  By the hydrorefining method of the present invention, the smoke point is improved with respect to a kerosene fraction having a low smoke point containing a large amount of two or more naphthenic hydrocarbons and aromatic hydrocarbons such as synthetic crude oil derived from oil sand. A kerosene base material can be obtained with good yield.

The present invention is described in detail below.
The kerosene fraction used as a raw material in the present invention includes a fraction having a boiling point of 140 to 280 ° C. containing 8% by mass or more of two or more naphthene hydrocarbons and 18% by mass or more of aromatic hydrocarbons. A fraction containing 90% by mass or more. The origin of this kerosene fraction is not particularly limited, and examples thereof include petroleum-based crude oil, synthetic crude oil derived from oil sand, bitumen reformed oil, and coal liquefied oil. Moreover, these 2 types or more can also be mixed and used.

When the proportion of naphthenic hydrocarbons of two or more rings in the kerosene fraction is less than 8% by mass and the proportion of aromatic hydrocarbons is less than 18% by mass, the fraction having a boiling point in the range of 140 to 280 ° C. is 90% by mass. If it is less than 1, lightening due to the reaction is likely to occur, and the yield of the kerosene base material is remarkably lowered. For this reason, the kerosene fraction preferably contains 90% by mass or more, more preferably 95% by mass or more of a fraction having a boiling point in the range of 140 to 280 ° C.
The boiling point means that measured in accordance with “Petroleum products—distillation test method—atmospheric pressure distillation test method” defined in JIS K 2254.

A kerosene fraction containing 12% by mass or more of naphthenic hydrocarbons having two or more rings is preferable because it can greatly improve the smoke point, and a kerosene fraction containing 15% by mass or more is more preferred. On the other hand, the upper limit of the content of two or more naphthenic hydrocarbons in the kerosene fraction is preferably 40% by mass or less, more preferably 35% by mass or less from the viewpoint of preventing an increase in hydrogen consumption in the hydrotreating apparatus. 30% by mass or less is more preferable.
Furthermore, the lower limit of the content of aromatic hydrocarbons in the kerosene fraction needs to be 18% by mass or more, more preferably 20% by mass or more, and more preferably 22% by mass or more from the viewpoint of suppressing the yield reduction of the kerosene base material. Further preferred. On the other hand, the upper limit of the content of aromatic hydrocarbons in the kerosene fraction is preferably 30% by mass or less, more preferably 27% by mass or less, and more preferably 25% by mass from the viewpoint of preventing an increase in hydrogen consumption in the hydrotreating apparatus. The following is more preferable.

The boiling point means that measured in accordance with “Petroleum products—distillation test method—atmospheric pressure distillation test method” defined in JIS K 2254.
Moreover, the method of calculating | requiring content of an aromatic hydrocarbon and a 2 or more ring naphthenic hydrocarbon is shown below. First, aromatic hydrocarbons and saturated hydrocarbons are fractionated by a method according to ASTM D 2549 “Standard Test Method for Separation of Representative Aromatics and Nonaromatics Fractions of High-Boiling Oils by Elution Chromatography”, and the contents of each are determined. To do. Further, the saturated hydrocarbon is analyzed by GC-TOFMS, and the content of two or more naphthenic hydrocarbons is determined.

The hydrorefining of the kerosene fraction in the present invention is carried out under a high-temperature and high-pressure condition in a hydrogen atmosphere by charging a catalyst in a fixed bed reactor.
The reaction pressure (hydrogen partial pressure) is preferably 2 to 6 MPa, more preferably 3 to 5 MPa. If the reaction pressure is less than 2 MPa, the desulfurization activity tends to decrease, and if it exceeds 6 MPa, the hydrogen consumption increases, the operating cost increases, and the production of naphtha increases.
The reaction temperature is preferably in the range of 260 to 340 ° C, more preferably 300 to 330 ° C. If the reaction temperature is less than 260 ° C., desulfurization activity and smoke point improvement tend to decrease, which is not practical. Moreover, when it exceeds 340 degreeC, since the production | generation of naphtha will become remarkable and a hue will deteriorate, it is unpreferable.
The liquid space velocity is not particularly limited, but is preferably 0.5 to 5 h ⁻¹ . If the liquid space velocity is less than 0.5 h ⁻¹ , the throughput is low and the productivity is low, which is not practical. On the other hand, if it exceeds 5 h ⁻¹ , the reaction temperature tends to be high, and lightening and hue deterioration tend to be observed.
The hydrogen / oil ratio is preferably in the range of 20 to 150 Nm ³ / kl, more preferably 50 to 120 Nm ³ / kl. A hydrogen / oil ratio of less than 20 Nm ³ / kl is not preferable because the desulfurization activity tends to be greatly reduced. Moreover, even if it exceeds 150 Nm ³ / kl, there is no significant change in the smoke point improvement, which is not preferable because it only increases the operating cost.

The hydrorefining in the present invention is performed using a fixed bed reactor, and this reaction tower is filled with a catalyst containing no zeolite and a catalyst containing USY zeolite.
The support of the catalyst not containing zeolite is not particularly limited, and metal oxides such as alumina, silica, titania and the like often used in desulfurization catalysts can be used.
In addition, the catalyst containing no zeolite is used with at least one metal selected from Group 6 of the periodic table supported on the carrier. Particularly preferred are molybdenum and tungsten. The amount of the metal supported on the entire catalyst is preferably 5 to 30% by mass. If it is less than 5% by mass or more than 30% by mass, the desulfurization activity is greatly reduced, which is not preferable. There are no particular restrictions on the loading method, but the easy and economical Incipient Wetness method is the best.
Further, it is preferable to support cobalt, nickel, or both together with a Group 6 metal of the periodic table as a co-catalyst because the smoke point is improved. There is no particular limitation on the amount of the cocatalyst supported with respect to the entire catalyst, but it can be supported and used usually in the range of 0.2 to 8% by mass.

The support of the catalyst containing USY zeolite consists of USY zeolite and a binder. The USY zeolite used here has an average particle size of 0.5 μm or less, more preferably 0.3 μm or less. When this average particle diameter exceeds 0.5 μm, the smoke point of kerosene is lowered and naphtha tends to be generated, which is not preferable.
Although there is no restriction | limiting in particular in the cayban ratio (silica / alumina molar ratio) of USY zeolite, 30-100 are preferable, More preferably, it is 40-70. When the Keiban ratio is less than 30, lightening is likely to proceed, and as a result, the cetane number tends to decrease, such being undesirable. On the other hand, if the Kayban ratio exceeds 100, it is difficult to cause ring opening of naphthene, and as a result, there is a tendency that improvement in smoke point is not observed. Although there is no restriction | limiting in the mass ratio of the USY zeolite with respect to a support | carrier, Usually, it can use in 5-70 mass%. If it is less than 5% by mass, ring opening of naphthene tends to be insufficient, and if it exceeds 70% by mass, the catalyst strength tends to be weak, which is not preferable.
The binder is not particularly limited, and alumina, silica, titania, silica alumina, silica zirconia, silica titania, alumina boria and the like can be used.

The catalyst containing USY zeolite is used by supporting at least one metal selected from Group 6 of the periodic table on the carrier. Particularly preferred as supported metals are molybdenum and tungsten. The amount of the metal supported on the whole catalyst is preferably 5 to 25% by mass. If it is less than 5% by mass or more than 25% by mass, the desulfurization activity is greatly reduced, which is not preferable. The supporting method is not particularly limited, but the easy and economical Incipient Wetness method is the best.
In addition, it is preferable to support cobalt, nickel, or both together with a Group 6 metal of the periodic table as a cocatalyst because desulfurization activity and smoke point are improved. There is no particular limitation on the amount of the cocatalyst supported with respect to the entire catalyst, but it can be supported and used usually in the range of 0.2 to 8% by mass.

  The filling ratio of the catalyst not containing zeolite and the catalyst containing USY zeolite is not particularly limited, but the latter ratio to the total catalyst amount is preferably 5 to 50% by volume. If it is less than 5% by volume, ring opening of naphthene does not occur easily, and the improvement in smoke point tends to decrease, such being undesirable. On the other hand, if it exceeds 50% by volume, naphtha is produced and the kerosene yield tends to decrease, which is not preferable.

  There are no particular restrictions on the method of filling the catalyst containing no zeolite and the catalyst containing USY zeolite, but a method of filling both the materials by uniformly physically mixing them and a catalyst whose catalyst layer does not contain zeolite from the inlet of the fixed bed reactor, USY A method of laminating and filling a catalyst containing zeolite and a catalyst not containing zeolite is preferable because they are effective in improving the smoke point.

  EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these.

Example 1
Kerosene fraction obtained by distillation from Middle Eastern crude oil (boiling point range: 160 to 260 ° C., bicyclic or higher naphthene content: 3.3% by mass, aromatic content: 18.6% by mass, smoke point: 24.0 mm ) And kerosene fraction obtained by distillation from oil sand synthetic crude oil produced by Sinclude (Canada) (boiling point range: 171 to 267 ° C., naphthene content of 2 or more rings: 28.6% by mass, aromatic content: 21.%). 5 mass%, smoke point: 16.5 mm) are mixed at a ratio of 50:50 (mass ratio), and the raw kerosene fraction for hydrorefining (boiling point range: 160 to 267 ° C., naphthene content of 2 or more rings: 16.0% by mass, aromatic content: 20.1% by mass, smoke point: 20.0 mm).

The solid acid catalyst containing no zeolite was prepared by supporting cobalt and molybdenum by the Incipient Wetness method on alumina as a support and calcining at 550 ° C. for 3 hours. At this time, the ratios of cobalt and molybdenum to the catalyst were 4.6% by mass and 19.8% by mass, respectively, in terms of oxide.
The catalyst containing USY zeolite carries nickel and tungsten on a carrier consisting of 50% by mass of alumina and 50% by mass of USY zeolite having an average particle size of 0.3 μm and a cayvan ratio of 30 by the Incipient Wetness method and calcining at 550 ° C. for 3 hours Prepared. At this time, the ratio of nickel and tungsten to the catalyst was 3.2% by mass and 18.7% by mass, respectively, in terms of oxide.

The fixed bed reactor was filled with three layers of a solid acid catalyst containing no zeolite, a catalyst containing USY zeolite, and a solid acid catalyst containing no zeolite from the inlet to the outlet of the reaction tower. Each catalyst ratio at this time is 70:10:20 (volume ratio).
Prior to hydrorefining, the charged catalyst was subjected to sulfidation treatment at 350 ° C. for 24 hours using a mixed gas of hydrogen (95% by volume) and hydrogen sulfide (5% by volume) and activated.
The hydrorefining was carried out under the conditions of a reaction temperature of 315 ° C., a pressure of 3.5 MPa, a hydrogen oil ratio of 85 Nm ³ / kl, and a liquid space velocity of 2.0 h ⁻¹ .
Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

For kerosene fraction, raw kerosene fraction, product oil and naphtha, boiling point means that measured according to “Petroleum products-Distillation test method-Atmospheric pressure distillation test method” prescribed in JIS K 2254. The content of aromatic hydrocarbons and naphthenic hydrocarbons having two or more rings is first determined by ASTM D 2549 “Standard Test Method for Separation of Representative Aromatics and Nonaromatics Fractions of High-Boiling Oils by Elution Chromatography "is fractionated by the method, each content is determined, further saturated hydrocarbons are analyzed by GC-TOFMS, the content of naphthenic hydrocarbons of two or more rings is obtained, The smoke point was measured in accordance with “Petroleum products—kerosene and aviation turbine fuel oil—smoke point test method” defined in JIS K2537.
The naphtha yield of the product oil is determined from the amount of distillate from 40 ° C. to 145 ° C. in accordance with “Petroleum products—distillation test method—gas chromatographic method distillation test method” defined in JIS K 2254.

(Example 2)
Hydrorefining was carried out using the same catalyst and packing method as in Example 1 except that the USY zeolite had a cayban ratio of 50. Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

(Example 3)
Hydrorefining was carried out using the same catalyst as in Example 2 except that the catalyst lamination ratio was 50:30:20 (volume ratio). Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

Example 4
Example 3 except that cobalt and molybdenum (supported in terms of oxides, 3.9% by mass and 20.1% by mass, respectively) were supported on a support having a cayban ratio of USY zeolite of 30. Hydrogenation purification was performed using Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

(Example 5)
Hydrogenation purification was performed using the same catalyst as in Example 2 except that the solid acid catalyst not containing zeolite and the catalyst containing USY zeolite were uniformly physically mixed and packed. Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

(Example 6)
Hydrorefining was performed using the same catalyst and filling method as in Example 2 except that the pressure was 5.0 MPa, the hydrogen oil ratio was 120 Nm ³ / kl, and the liquid space velocity was 3.0 h ^−1. It was. Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

(Example 7)
Mixed kerosene fraction (boiling point range: 160 to 267 ° C., bicyclic or higher naphthene fraction: 21) in which the mixing ratio of the Middle East kerosene fraction and the oil sand synthetic crude oil kerosene fraction was 30:70 (mass ratio) 0.0 wt%, aromatic content: 20.6 wt%, smoke point: 18.5 mm), and hydrorefining was performed using the same catalyst and packing method as in Example 1. It was. Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

(Comparative Example 1)
Hydrorefining was performed using the same packing method as in Example 1 except that USY zeolite having an average particle size of 1.1 μm (Kayban ratio 30) was used. Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

(Comparative Example 2)
Hydrorefining was performed using the same packing method as in Example 2 except that USY zeolite having an average particle size of 1.1 μm (Kayban ratio 50) was used. Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

(Comparative Example 3)
Hydrorefining was carried out using the same catalyst and filling method as in Example 1 except that Y-type zeolite having an average particle size of 0.3 μm (Kayban ratio 7) was used instead of USY zeolite. Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

(Comparative Example 4)
Mixed kerosene fraction (boiling point range: 160-267 ° C., bicyclic or higher naphthene fraction: 4) in which the mixing ratio of the Middle East kerosene fraction and the oil sand synthetic crude oil kerosene fraction was 95: 5 (mass ratio) .5 mass%, aromatic content: 18.7 mass%, smoke point: 23.5 mm), and hydrorefining was performed using the same catalyst and filling method as in Example 1. It was. Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

(Comparative Example 5)
A fraction obtained by distillation from Middle Eastern crude oil (boiling point range: 190 to 295 ° C., bicyclic or higher naphthene content: 8.2 mass%, aromatic content: 22.5 mass%, smoke point: 19.5 mm) And a fraction obtained by distillation from oil sand synthetic crude oil produced by Cincrude (Canada) (boiling range: 200 to 300 ° C., bicyclic or higher naphthene content: 39.1% by mass, aromatic content: 23.6% by mass) , Smoke point: 14.0 mm) are mixed at a ratio of 50:50 (mass ratio), and hydrorefining raw material gas oil fraction (boiling range: 190 to 300 ° C. (boiling point 280 ° C. + fraction: 25 mass%) 2) or more naphthene content: 23.7% by mass, aromatic content: 23.1% by mass, smoke point: 16.5 mm) Used for hydrorefining. Table 1 shows the naphtha (boiling point: 40 to 145 ° C.) yield and smoke point of the product oil.

  As described above, a kerosene fraction containing 8% by mass or more of two or more naphthenic hydrocarbons and 18% by mass or more of aromatic hydrocarbons and 90% by mass or more of a fraction having a boiling range of 140 to 280 ° C. And a solid acid catalyst containing no zeolite carrying a metal of group 6 of the periodic table and a catalyst containing USY zeolite having an average particle diameter of 0.5 μm or less and carrying a metal of group 6 of the periodic table By filling the fixed bed reactor and carrying out hydrorefining, the smoke point of the raw kerosene fraction can be improved and the kerosene substrate can be produced with good yield.

  By the method of the present invention, a kerosene base material having an improved smoke point can be obtained with a high yield, and thus the industrial value is great.

Claims (8)

  A kerosene fraction containing 90% by mass or more of a fraction having a boiling range of 140 to 280 ° C., containing 8% by mass or more of naphthenic hydrocarbons of 2 or more rings and 18% by mass or more of aromatic hydrocarbons as a raw material, A fixed bed reactor packed with a solid acid catalyst containing no zeolite carrying a Group 6 metal and a catalyst containing USY zeolite with a mean particle size of 0.5 μm or less carrying a Group 6 metal of the periodic table The hydrorefining method of a kerosene fraction characterized by carrying out the hydrorefining process in the.   The method for hydrorefining a kerosene fraction according to claim 1, wherein a ratio of two or more naphthenic hydrocarbons in the kerosene fraction is 12% by mass or more.   The catalyst is stacked and packed in the order of a solid acid catalyst containing no zeolite, a catalyst containing USY zeolite, and a solid acid catalyst containing no zeolite from the inlet of the fixed bed reactor. 3. A method for hydrorefining a kerosene fraction according to 2.   The kerosene fraction according to any one of claims 1 to 3, wherein a solid acid catalyst not containing zeolite and a catalyst containing USY zeolite are uniformly physically mixed and packed in a fixed bed reactor. Hydrorefining method.   Hydrogenation of kerosene fraction according to any one of claims 1 to 4, characterized in that the proportion of the catalyst comprising USY zeolite relative to the total catalyst capacity charged in the fixed bed reactor is 5 to 50% by volume. Purification method.   The method for hydrotreating kerosene fraction according to any one of claims 1 to 5, wherein the silica / alumina ratio of USY zeolite is 30 to 100 (mol / mol). The reaction temperature is 260 to 340 ° C, the pressure is 2 to 6 MPa, the hydrogen oil ratio is 20 to 150 Nm ³ / kl, and the liquid space velocity is 0.5 to 5.0 h ^-1. The method for hydrorefining a kerosene fraction according to any one of the above.   The method for hydrorefining a kerosene fraction according to any one of claims 1 to 7, wherein the kerosene fraction contains a kerosene fraction derived from an oil sand.