JPH07197039A - Method for hydrodesulfurizing gas oil - Google Patents

Abstract

PURPOSE:To obtain a liq. fuel with a low sulfur content at a low cost by the depth hydrodesulfurization of a gas oil. CONSTITUTION:A liq. fuel is obtd. by the depth hydrodesulfurization of at least one gas oil in the presence of a catalyst. The gas oil is selected from the group consisting of a catalytic cracking gas oil, a thermal cracking gas oil, a straight-run gas oil, a coker gas oil, a hydrogenated gas oil, and a desulfurized gas oil and has a b.p. range of 250-400 deg.C) and a sulfur content of 3wt.% or lower. The catalyst is obtd. by impregnating a carrier comprising 80-99wt.% inorg. oxide and 1-20wt.% zeolite with a group VI metal component in an amt. of 10-30wt.% (in terms of the oxide) and a group VIII metal component in an amt. of 1-10wt.% (in terms of the oxide). The catalytic reaction is conducted under a pressure of 30-80kg/cm<2> at 320-360 deg.C at a liq. space velocity of 0.5-5.0hr<-1> in a hydrogen/oil ratio of 100-400l/l and in such a manner that the resulting liq. fuel contains 0.005-0.10wt.% sulfur.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for hydrodesulfurizing light oil, and more particularly to a method for deeply desulfurizing light oil under a specific condition using a specific catalyst.

[0002]

The gas oil fraction obtained by distillation or cracking of crude oil generally contains sulfur compounds, and when these oils are used as fuel, they are present in the sulfur compounds. Sulfur is converted into sulfur compounds such as oxides and released into the atmosphere. Further, when used in a diesel engine, there is also an adverse effect on a device for removing NOx and the like, so it is desirable that the above-mentioned fraction has as low a sulfur content as possible. A gas oil fraction having a low sulfur content can be obtained by catalytic hydrodesulfurization of a gas oil fraction.

By the way, catalysts conventionally used for hydrodesulfurization of hydrocarbon oils are usually metals of Group VI of the periodic table (hereinafter, simply referred to as "Group VI metal") and Group VIII of the periodic table. A group metal (hereinafter, simply referred to as "Group VIII metal") is supported as an active metal on an oxide carrier such as alumina, magnesia or silica. At this time, generally, Mo or W is used as the Group VI metal, and Co or Ni is used as the Group VIII metal.

In order to improve the activity of this catalyst, phosphorus,
A technique of adding boron or the like has been reported (Japanese Patent Laid-Open No. Sho 5)
No. 2-1503). Further, a technique of mixing zeolite into an inorganic oxide used as a carrier has also been reported (see JP-A-56-20087). Moreover, techniques using both of them have been reported (Japanese Patent Laid-Open No. 61-126196, Japanese Laid-Open Patent Publication No. 2-21454).
(See Japanese Patent Publication No. 4).

However, these prior proposed techniques are mainly aimed at hydrodesulfurization or hydrocracking of heavy oil fractions of hydrocarbon oils, and mainly focus on deep hydrodesulfurization of light oil fractions. It's not the technology I used.

Further, in recent years, as the regulation of sulfur content in commercial gas oil has become stricter due to environmental problems (0.5 wt% → 0.05 wt%), deeper desulfurization is required, and difficult desulfurization in this area is required. 4M, which is regarded as a sexual substance
-DBT (4 methyldibenzothiophene) and 4,6DM
-Treatment of non-desulfurizable substances centered on DBT (4,6 dimethyldibenzothiophene) has become necessary.

The present invention has been made in view of such circumstances of the prior art, and uses a catalyst that exhibits excellent desulfurization activity in the deep desulfurization region and can sufficiently cope with difficult desulfurization substances. An object of the present invention is to provide a method for hydrodesulfurizing light oil.

[0008]

As a result of repeated studies to achieve the above object, the inventors of the present invention surprisingly include an inorganic oxide, a zeolite, a Group VI metal and a Group VIII metal. Under certain reaction conditions, the catalyst should contain 0.10 wt% or less of sulfur contained in light oil, and even 0.05 wt.
The inventors have found that they exhibit excellent performance in a hydrodesulfurization reaction in which they are desulfurized to less than 100%, and can sufficiently cope with substances that are said to be difficult to desulfurize, and have completed the present invention.

That is, the present invention is at least one of catalytically cracked gas oil, thermally cracked gas oil, straight-run gas oil, coker gas oil, hydrotreated gas oil and desulfurized gas oil, and has a boiling point range of 150 to 400 ° C. and sulfur. A raw material oil having a content of 3% by weight or less, and a carrier containing 80 to 99% by weight of an inorganic oxide and 1 to 20% by weight of a zeolite, and a Group VI metal component of the periodic table of 10 to 30 in terms of oxide. Weight% and Periodic Table VI
Using a catalyst containing a Group II metal in an amount of 1 to 10% by weight in terms of oxide, the pressure (hydrogen partial pressure) is 30 to 80 kg / c.
m ² , temperature 320 to 360 ° C., liquid hourly space velocity 0.5 to
5.0 hr ⁻¹ , hydrogen / oil ratio of 100 to 400 liters / liter (hereinafter, liter is referred to as “L”), and sulfur content of produced oil is 0.005 to 0.1% by weight.
A method for hydrodesulfurizing gas oil is characterized by carrying out a catalytic reaction so that

The present invention will be described in detail below. The catalyst carrier used in the present invention contains an inorganic oxide and zeolite. Among these, as the inorganic oxide,
Various substances can be used, for example, silica, alumina, boria, magnesia, titania, silica-alumina, silica-magnesia, silica-zirconia, silica-tria, silica-berrillia, silica-titania, silica-boria, alumina-zirconia. , Alumina-titania, alumina-boria, alumina-chromia, titania-zirconia, silica-alumina-tria, silica-alumina-zirconia, silica-alumina-magnesia, silica-magnesia-zirconia, among others, among them,
Alumina, silica-alumina, alumina-boria, alumina-titania and alumina-zirconia are preferable, and γ-alumina among alumina is particularly preferable. These inorganic oxides can be used alone or in combination of two or more kinds.

On the other hand, various kinds of zeolite can be used, for example, A-type zeolite, X-type zeolite,
Examples thereof include Y-type zeolite, stabilized Y-type zeolite, ultra-stable Y-type zeolite, L-type zeolite, and ZSM-type zeolite. Among them, HY-type zeolite and stabilized Y-type zeolite are preferable. These crystalline zeolites can be used alone or in combination of two or more kinds.

The content ratio of the inorganic oxide in the carrier is
It is 80 to 99% by weight, preferably 85 to 98% by weight, and the content ratio of the zeolite is 1 to 20% by weight, preferably 2 to 15% by weight.

When the content of the inorganic oxide is less than 80% by weight, the surface of the catalyst becomes small and the meaning as a carrier is lost, and when it exceeds 99% by weight, the content of zeolite is relatively less than 1% by weight. Therefore, the technical significance of containing zeolite does not appear, and when the amount of zeolite exceeds 20% by weight, the dispersibility of the active metal deteriorates.

The carrier containing the above-mentioned inorganic oxide and zeolite includes montmorillonite, kaolin, halosite,
Clay minerals such as bentonite, adaval guide, bauxite, kaolinite, nacrite and anoxite may be contained alone or in combination of two or more.

The specific surface area, pore volume, and average pore diameter of the carrier composed of the above components are not particularly limited, but in order to make it a catalyst for removing even difficult-to-desulfurize substances, The specific surface area is preferably 250 m ² / g or more, the pore volume is preferably 0.3 to 1.2 cc / g, and the average pore diameter is preferably 50 to 130 Å.

As the Group VI metal component contained in the above carrier, various compounds can be used, but compounds of chromium, molybdenum and tungsten are preferable, and compounds of molybdenum and tungsten are particularly preferable. Specific examples of these compounds include (NH ₄ ) ₆ Mo ₇ O ₂₄ · 4H ₂
Ammonium molybdate represented by O, _(NH 4)
₁₀ W ammonium tungstate represented by ₁₂ O ₄₁ · 5H ₂ O, molybdenum oxide represented by MoO _3, H
_{3 (PMo 12 O 40) ·} 30H molybdophosphoric acid represented by _{2 O,} etc. tungstophosphoric acid represented by _{H 3 (PW 12 O 40)} · 30H 2 O and the like. These compounds can be used alone or in combination of two or more kinds.

As the Group VIII metal component to be contained together with the Group VI metal component, various compounds can be used, but compounds such as iron, cobalt, nickel, rhodium, palladium, osmium, iridium and platinum are preferable. Particularly, carbonates, acetates and phosphates of cobalt and nickel are preferable. These compounds may be used alone or
Combinations of more than one species can be used.

The content ratio of these Group VI and Group VIII metal components is 10 to 30% by weight, preferably 15% by weight, based on the weight of the catalyst, in terms of oxide.
Is about 23 to 23% by weight, and the Group VIII metal component is about 1 to 1
It is 0% by weight, preferably 3 to 7% by weight.

When the amount of the Group VI metal component is less than 10% by weight, even the hardly desulfurizable substance cannot be efficiently removed, and when it exceeds 30% by weight, the dispersibility of the active metal is deteriorated. In addition, this effect is saturated and becomes uneconomical. When the content of the Group VIII metal component is less than 1% by weight, the technical significance of containing the Group VIII metal component does not appear, and thus even the hardly desulfurizable substance cannot be efficiently removed. Even if it exceeds%, this effect is saturated and becomes uneconomical.

The method of incorporating the above-mentioned Group VI metal component and Group VIII metal component into the carrier, that is, the method of preparing the catalyst used in the present invention, can be carried out by using some known techniques. it can. As one method thereof, a solution obtained by dissolving the above-mentioned Group VI metal compound and the above-mentioned Group VIII metal compound in the above-mentioned carrier in a solvent such as water, alcohols, ethers, ketones, An impregnation method in which one or more steps of impregnation are used for supporting is mentioned. In this impregnation method, when the number of impregnation treatments is plural, drying and firing may be performed between each impregnation treatment.

As another method, a spraying method in which a solution in which the above-mentioned Group VI metal compound and the above-mentioned Group VIII metal compound are dissolved is sprayed on the above carrier, or a Group VI metal component and Group VIII are sprayed. A chemical vapor deposition method of chemically vapor depositing a group metal component can be mentioned.

As still another method, a kneading method or a coprecipitation method in which the above-mentioned carrier component before molding contains a part or all of the above-mentioned Group VI metal component and Group VIII metal component, and is molded. The alkoxide method can be mentioned.

The specific surface area, pore volume and average pore diameter of the catalyst of the present invention prepared by the above various production methods are
Although not particularly limited, as in the case of the above-mentioned carrier, in order to efficiently remove even the hardly desulfurizable substance, the specific surface area is 200 m ² / g or more and the pore volume is 0.3.
˜1.2 cc / g and average pore size 60 to 120Å are preferred.

The shape of the catalyst is not particularly limited, and various shapes usually used for this kind of catalyst,
For example, a columnar shape, a four-leaf type, or the like can be adopted.
As for the size, usually, the diameter is preferably 1/10 to 1/22 inch and the length is preferably 3.2 to 3.6 inch.

When the above catalyst is used in the actual process to which the present invention is applied, it may be used alone, or may be used as a mixture with a known catalyst or a known inorganic oxide carrier. Further, the above catalyst, montmorillonite, kaolin, halosite, bentonite, adaval guide, bauxite, kaolinite, nacrite,
Clay minerals such as anoxite, alone or 2
It is also possible to include a combination of two or more species.

In the present invention using the above catalyst, as the feedstock oil, catalytically cracked gas oil, thermally cracked gas oil, straight run gas oil,
Examples include coker gas oil, hydrotreated gas oil, and desulfurized gas oil, which can be used alone or in combination of two or more, and have a boiling point range of 150 to
The temperature is 400 ° C, preferably 200 to 380 ° C, more preferably 220 to 340 ° C, and the sulfur content is 3% by weight or less, preferably 2.5% by weight or less, more preferably 2.0% by weight or less.

In the present invention, the conditions for the hydrodesulfurization reaction of the feed oil are a pressure (hydrogen partial pressure) of 30 to 8
0 kg / cm ² , preferably 50-60 kg / cm ² ,
The temperature is 320 to 360 ° C., preferably 330 to 360
C., liquid hourly space velocity is 0.5 to 5.0 hr ⁻¹ , preferably 1.0 to 2.0 hr ⁻¹ , hydrogen / oil ratio is 100 to 4
00 L / L, preferably 200 to 300 L / L can be mentioned.

If the pressure (hydrogen partial pressure) is less than 30 kg / cm ² , even the hardly desulfurizable substance cannot be removed, and even if it exceeds 80 kg / cm ² , the removal efficiency of the hardly desulfurized substance is high. Not only is it saturated, but expensive equipment that can withstand such high pressures is required, which is uneconomical. Temperature is 320 ℃
If it is less than this, even the hardly desulfurizable substance cannot be removed, and even if it exceeds 360 ° C, the removal efficiency of the hardly desulfurizable substance is saturated, which is uneconomical. If the liquid hourly space velocity exceeds 5.0 hr ^-1 , the contact time between the catalyst and the feedstock becomes too short, and even the hardly desulfurizable substance cannot be removed.
Even if it is less than r ^-1 , not only the contact effect is saturated, but also the treatment efficiency is lowered.

The reaction conditions are such that the sulfur content in the produced oil is 0.005 to 0.1% by weight, preferably 0.01 to 0.
The conditions are selected such that the content is 08% by weight, more preferably 0.03 to 0.07% by weight. Under such conditions, the life of the above catalyst becomes equal to or longer than the life of a typical conventional catalyst, and it becomes possible to use the above catalyst for one year or more in an actual apparatus.

In carrying out the present invention in which the above feed oil is hydrodesulfurized under the above conditions on a commercial scale, the above catalyst is used in a suitable reactor as a fixed bed, moving bed or fluidized bed, The feedstock oil may be introduced into the reactor and treated under predetermined conditions.

Most commonly, the catalyst described above is maintained as a fixed bed with the feedstock passing downwardly through the fixed bed. The catalyst can be used in a single reactor,
It is also possible to use several reactors in series.

[0032]

【Example】

Example 1 A carrier having a specific surface area of 372 m ² / g and a pore volume of 0.6
5 cc / g, average pore size 62Å, HY-type zeolite [SiO ₂ / Al ₂ O ₃ molar ratio 6, Na ₂ O content 0.
3% by weight or less, surface area 900 to 1100 (Langmu
ir, m ² / g) and 600-700 (BET, m ²
/ G), crystal size 0.7-1.0 μm] 5 wt% γ-alumina is used, and Mo is used as a Group VI metal.
A desulfurization reaction was performed under the conditions shown in Table 1 using a catalyst containing 5 wt% (oxide) and 5 wt% Co (oxide) as a Group VIII metal. The results are shown in Table 4.

[0033]

[Table 1]

Example 2 As a carrier, a specific surface area of 387 m ² / g and a pore volume of 0.6
5 cc / g, average pore diameter 61Å, 10% by weight of HY-type zeolite (the same HY-type zeolite as in Example 1) γ
-The desulfurization reaction was performed in the same manner as in Example 1 except that alumina was used. The results are also shown in Table 4.

Example 3 As a carrier, a specific surface area of 405 m ² / g and a pore volume of 0.6
5 cc / g, average pore diameter 67Å, and 20% by weight of HY-type zeolite (HY-type zeolite same as in Example 1) γ
-The desulfurization reaction was performed in the same manner as in Example 1 except that alumina was used. The results are also shown in Table 4.

Example 4 A carrier having a specific surface area of 350 m ² / g and a pore volume of 0.6
1cc / g, average pore diameter 60Å, 1% by weight of HY-type zeolite (the same HY-type zeolite as in Example 1) γ-
The desulfurization reaction was performed in the same manner as in Example 1 except that alumina was used. The results are also shown in Table 4.

Example 5 A desulfurization reaction was carried out in the same manner as in Example 1 except that the Mo content was 15% by weight and the Co content was 3% by weight. The results are also shown in Table 4.

Example 6 The desulfurization reaction was performed in the same manner as in Example 1 except that the Mo content was 15% by weight and the Co content was 8% by weight. The results are also shown in Table 4.

Example 7 The desulfurization reaction was carried out in the same manner as in Example 1 except that the Mo content was 25% by weight and the Co content was 3% by weight. The results are also shown in Table 4.

Example 8 The desulfurization reaction was carried out in the same manner as in Example 1 except that the Mo content was 25% by weight and the Co content was 8% by weight. The results are also shown in Table 4.

Example 9 The desulfurization reaction was carried out in the same manner as in Example 1 except that W was used instead of Mo. The results are also shown in Table 4.

Example 10 A desulfurization reaction was performed in the same manner as in Example 1 except that Ni was used instead of Co. The results are also shown in Table 4.

Example 11 A desulfurization reaction was carried out in the same manner as in Example 1 except that W was used instead of Mo and Ni was used instead of Co. The results are also shown in Table 4.

Comparative Example 1 As a carrier, a specific surface area of 336 m ² / g and a pore volume of 0.7
The desulfurization reaction was performed in the same manner as in Example 1 except that γ-alumina having 1 cc / g and an average pore size of 68Å was used.
The results are shown in Table 5.

Comparative Example 2 A carrier having a specific surface area of 412 m ² / g and a pore volume of 0.6
Γ with 5 cc / g, average pore diameter of 60Å and containing 30% by weight of HY-type zeolite (HY-type zeolite same as in Example 1)
-The desulfurization reaction was performed in the same manner as in Example 1 except that alumina was used. D The results are also shown in Table 5.

Comparative Example 3 The desulfurization reaction was carried out in the same manner as in Example 1 except that the Group VI metal was not supported. The results are also shown in Table 5.

Comparative Example 4 The desulfurization reaction was carried out in the same manner as in Example 1 except that the Mo content was 15% by weight (oxide). This result
It is also shown in Table 5.

Comparative Example 5 A desulfurization reaction was carried out in the same manner as in Example 1 except that the Co content was 8% by weight (oxide). The results are also shown in Table 5.

Comparative Example 6 The desulfurization reaction was carried out in the same manner as in Example 1 except that the Co content was 35% by weight (oxide). This result
It is also shown in Table 5.

The compositions and properties of the catalysts used in the above Examples and Comparative Examples are shown in Tables 2 and 3, respectively.

[0051]

[Table 2]

[0052]

[Table 3]

[0053]

[Table 4]

[0054]

[Table 5]

Further, the produced oils obtained in the above Examples and Comparative Examples were put into a GC-AED analyzer to analyze a specific residual sulfur content. The results are shown in Tables 6 and 7. Table 6 shows the results of deep desulfurization at LHSV1.5, and Table 7 shows the results of deep desulfurization at LHSV3.0.

[0056]

[Table 6]

[0057]

[Table 7]

[0058]

As described in detail above, according to the present invention,
A fuel oil having a low sulfur content, which can sufficiently cope with desulfurization of 4M-DBT or 4,6DM-DBT, which is a problematic desulfurization substance having a sulfur content of 0.05% by weight,
It can be provided at low cost.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuo Ide 1134-2, Gongendo, Satte City, Saitama Prefecture Inside the Research and Development Center, Cosmo Research Institute Co., Ltd. (72) Osamu Chiyoda, 11342-2, Gongendo, Satte City, Saitama Prefecture Cosmo Research Institute Co., Ltd. R & D Center (72) Inventor Hatsutarou Yamazaki 1134-2 Gongendo, Satte City, Saitama Cosmo Research Institute R & D Center

Claims (1)

[Claims] 1. A catalytically cracked gas oil, a thermally cracked gas oil, a straight-run gas oil,
At least one of coker gas oil, hydrotreated gas oil, and desulfurized gas oil, having a boiling point range of 150 to 400
A raw material oil having a sulfur content of 3% by weight or less at a temperature of 0 ° C., a carrier containing 80 to 99% by weight of an inorganic oxide and 1 to 20% by weight of a zeolite, and a Group VI metal component of the periodic table in terms of oxide. Using a catalyst containing 10 to 30% by weight and Group VIII metal of the periodic table in an amount of 1 to 10% by weight in terms of oxide, pressure is 30 to 80 kg / cm ² and temperature is 320 to 360.
C, liquid hourly space velocity is 0.5 to 5.0 hr ^-1 , hydrogen / oil ratio is 100 to 400 liters / liter, and the sulfur content of the produced oil is 0.005 to 0.1% by weight. A method for hydrodesulfurizing light oil, which comprises carrying out a catalytic reaction.