JP2001179105A - Catalyst for hydrodesulfurization and isomerization of light hydrocarbon oil and method of producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catalyst capable of simultaneously facilitating both of desulfurization being an inevitable process as pre-treatment process for isomerization and the isomerization, which is useful in the technology for obtaining isomerized gasoline low in sulfur content by desulfurizing and isomerizing light hydrocarbon oil containing sulfur and to simplify necessary equipments and to suppress the running cost by using the same. SOLUTION: The catalyst is obtained by adding a sulfate group of 1 to 3 mass %, expressed in terms of sulfur, to a carrier of an oxide of or a hydroxide of zirconium, then incorporating 0.5 to 10 mass % platinum to the mixture and firing the resultant material at 550 to 800 deg.C to stabilize, and the catalyst has a specific surface area of 50 to 150 m2/g. The method of producing the catalyst comprises treating zirconium hydroxide with a treating agent capable of imparting the sulfate group, then impregnating a platinum compound and firing the resultant material at 550 to 800 deg.C, or before impregnating the platinum compound, firing at 550 to 800 deg.C, then impregnating the platinum compound and firing at 300 to 700 deg.C. The platinum compound can be supported by kneading.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention is capable of simultaneously achieving hydrodesulfurization and isomerization of a light hydrocarbon oil containing an organic sulfur compound, and can be used with a simpler facility than the prior art. A possible and economical catalyst for hydrodesulfurization isomerization of light hydrocarbon oils, and extends to a process for producing the catalyst.

[0002]

2. Description of the Prior Art Isomerization of light hydrocarbon oil is a technique which has been widely used in the petroleum refining industry and petrochemical industry. In particular, in recent years, with higher performance of engines of automobiles and aircraft, gasoline used as fuel has been required to have a high octane number, and isomerization has become important to meet the demand. Until now, as one of the light base materials of gasoline, a so-called isomerized gasoline obtained by isomerizing light naphtha, which is a light hydrocarbon oil, to improve the octane number has been used.

[0003] Many studies have been made on the method of isomerizing light hydrocarbon oils, and various catalysts used for the isomerization reaction are known. Examples of the catalyst include a solid acid catalyst. A method for producing a solid acid catalyst and an isomerization method using the same are described in, for example, Japanese Patent Publication No. 5-29503,
It is disclosed in Japanese Patent Publication No. 6-29199.

[0004] However, light hydrocarbon oils such as light naphtha, which are still fractions obtained by distilling crude oil, usually contain about 500 to 700 ppm of organic sulfur compounds, which become catalyst poisons for solid acid catalysts. Therefore, direct isomerization of light naphtha was not a process suitable for industrial implementation in terms of catalyst life. In the process currently being performed, first, it converts the light naphtha was treated with hydrodesulfurization catalyst such as Co-Mo / Al ₂ O ₃ and organic sulfur compounds to hydrogen sulfide, to separate the hydrogen sulfide from the product oil Thus, a two-stage operation of obtaining desulfurized light naphtha whose sulfur content has been reduced to several ppm or less and then using it as an isomerized feedstock oil is performed. That is, in the existing light hydrocarbon oil isomerization process, the hydrodesulfurization step is indispensable before the isomerization step.

[0005] If the catalyst used for isomerization of light hydrocarbon oils can be replaced with a catalyst capable of simultaneously achieving hydrodesulfurization and isomerization, hydrogenation which is indispensable for the isomerization process is required. The desulfurization step can be omitted, and the isomerization can be carried out economically with simpler equipment than in the prior art. Specifically, an existing light hydrocarbon oil isomerization reaction tower is charged with a sulfur-resistant isomerization catalyst, and a light hydrocarbon oil containing an organic sulfur compound is supplied as a raw material oil for isomerization, It is desirable to be able to perform hydrodesulfurization and isomerization reactions simultaneously.

[0006] The inventors of the present invention have conducted studies with the intention of responding to such a demand. As a result, certain solid acid catalysts have not only an isomerization activity for hydrocarbons but also a desulfurization activity for organic sulfur compounds. It was found to be useful as an isomerization catalyst having excellent sulfur resistance.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to utilize the above-mentioned new knowledge obtained by the present inventors to economically desulfurize and isomerize light sulfur-containing hydrocarbon oils with simple equipment. And a suitable production method thereof.

[0008]

The catalyst for hydrodesulfurization and isomerization of a light hydrocarbon oil according to the present invention is obtained by converting a sulfuric acid group into a sulfuric acid on a carrier comprising zirconium oxide or hydroxide. %, And 0.5 to 10% platinum.
It is characterized by having a specific surface area of 50 to 150 m < ² > / g.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

[0010] As described above, the catalyst of the present invention uses zirconium oxide or hydroxide as a carrier, and contains 1 to 3% by mass of sulfate as sulfur content, and platinum of 0.5 to 0.5%. 10% by weight, preferably 0.6 to 7% by weight,
More preferably, 0.7 to 5% by mass is supported. When the amount of platinum supported is less than 0.5% by mass, the active sites are too small to simultaneously perform isomerization and desulfurization. On the other hand, when the amount is more than 10% by mass, platinum has an acid site having super-strong acidity. In some cases, the activity is reduced due to the covering.

The amount of sulfate (SO ₄ ) given to the carrier is 1 to 3% by mass as sulfur (S), preferably 1.5 to 2%.
% By mass. If the amount of the sulfate group does not reach 1% by mass in terms of sulfur content, the acidity of the catalyst is low, so that the solid superacidity is weak and the activity as an isomerization catalyst is insufficient. When the amount is more than 3%, the surface of zirconia is excessively covered with sulfate groups and piled up, thereby crushing the active sites, and consequently the activity is reduced.

[0012] The sulfur content in the catalyst is measured by burning a sample in an oxygen stream and oxidizing S contained in the sample.
After removing the water and dust to O ₂ , detection and measurement are performed with an infrared absorption detector, for example, a solid state type detector. According to this analysis method, the amount of sulfur in the sample can be determined in a concentration range of 0.001 to 99.99%.

According to X-ray diffraction analysis, when the carrier is zirconium oxide (ZrO ₂ ), its crystal structure includes tetragonal and monoclinic. Those useful as catalyst carriers are tetragonal, and a high proportion of monoclinic structure results in low catalytic activity. The abundance ratio of the monoclinic structure and the tetragonal structure in zirconium oxide was determined by measuring the X-ray diffraction peak of the catalyst, and the peak of 2θ = 28.2 (the main peak of the monoclinic structure) and 2θ = The X-ray diffraction peak integrated intensity ratio with the peak of 30.2 (the main peak of the tetragonal structure) is determined. When the abundance ratio between the monoclinic structure and the tetragonal structure in zirconium oxide is calculated in this manner, the value is preferably in the range of monoclinic / tetragonal = 20/80 to 0/100. . A more preferred range is 10/90
０0/100.

After the catalyst of the present invention is calcined at 550 to 800 ° C. and has a specific surface area of 5
It must be in the range of 0 to 150 m ² / g. When the specific surface area is less than 50 m ² / g, the dispersibility of the supported metal is poor, and the number of active sites for hydroisomerization is small. In addition, the crystal structure of zirconium oxide also tends to have a monoclinic / tetragonal ratio greater than 20/80,
Not preferred. On the other hand, when the specific surface area exceeds 150 m ² / g, the crystallization of the zirconium oxide does not proceed by firing, and the ratio of the zirconium oxide tetragonal structure therein is low, so that the activity of hydrodesulfurization isomerization is low. It stays low.

The method for producing the catalyst of the present invention is not particularly limited, and the method of providing a sulfate group and supporting platinum and the order thereof are arbitrary, but the following production methods are preferred.

The first production method comprises treating zirconium hydroxide with a treating agent that gives a sulfate group thereto, impregnating with a platinum compound, and firing at a temperature of 550 ° C. to 800 ° C.

In the second production method, zirconium hydroxide is treated with a treating agent that gives a sulfate group to the zirconium hydroxide.
After firing at a temperature of 50 ° C. to 800 ° C., impregnation with a platinum compound is performed, followed by 300 ° C. to 700 ° C., preferably 50 ° C.
Baking again at a temperature of 0 ° C to 600 ° C.

A third production method is to knead zirconium hydroxide and a substance which gives a sulfate group thereto, and
After calcination at a temperature of 800 ° C., impregnation with a platinum compound is performed, and then 300 ° C. to 700 ° C., preferably 5 ° C.
Baking again at a temperature of 00 ° C to 600 ° C.

In a fourth production method, zirconium hydroxide is kneaded with a substance providing a sulfate group and a platinum compound,
Baking at a temperature of 550 ° C to 800 ° C.

As a treating agent for giving a sulfate group to a carrier which is an oxide or hydroxide of zirconium, 0.1 to 5 N
Of sulfuric acid, and an aqueous solution of ammonium sulfate having a concentration of 0.1 to 10 mol are representative. These treatment agents are used in an amount of 1 to 10 times the amount of the carrier. In addition, a similar effect can be obtained by using a treating agent such as hydrogen sulfide or sulfurous acid gas to give a sulfate group after the firing stabilization treatment.

The sulfate group may be provided by kneading not only the above-mentioned liquid or gaseous state as a sulfuric acid treating agent but also a solid state with a carrier. By stabilizing, a similar effect can be obtained. As a kneading means, any kneading machine generally used for catalyst preparation can be used. In kneading, an appropriate liquid, for example, water, ethanol, isopropanol, acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, or the like is added. There are no particular restrictions on the order of addition of the carrier, the sulfate treatment agent, the solvent, and the like, and the kneading temperature and time are not particularly limited as long as the performance of the catalyst is not affected.

A typical method of supporting platinum on a catalyst is an impregnation method in which a carrier is immersed in an aqueous solution of a platinum compound such as chloroplatinic acid or a tetraammineplatinum complex, pulled up and dried. It is also possible to carry platinum by mixing chloroplatinic acid, tetraammineplatinum complex or the like at the time of kneading with the above-mentioned sulfate group treating agent instead of impregnation with an aqueous solution.

The firing stabilization treatment is performed under an oxidizing atmosphere.
550-800 ° C, preferably 600-750 ° C
By heating to a temperature in the range of 0.5 to 10 hours. When the firing temperature is lower than 550 ° C., the ratio of zirconium hydroxide contained in the zirconium compound is large,
Since the proportion of the tetragonal zirconium oxide is small, the properties of the solid acid are not exhibited, and the catalyst does not have hydrodesulfurization isomerization activity. On the other hand, when heated at a high temperature, the amount of hydroxide decreases, but when the temperature exceeds 800 ° C., the proportion of monoclinic zirconium oxide increases, which is not preferable for the catalytic activity. In addition, since the sulfate is also eliminated, the amount of sulfur in the catalyst becomes less than 1% by mass, and the solid acid strength decreases. Furthermore, sintering of platinum also occurs, and the active sites of hydrodesulfurization isomerization decrease. If the catalyst is stabilized in a calcination stabilizing treatment in a reducing atmosphere, the activity of the sulfate groups on the platinum or platinum compound changes, and the catalytic activity decreases due to the reduction of the sulfate groups, which is considered to be caused by reductive decomposition. .

The firing stabilization treatment may be performed before or after carrying platinum. Even when firing is stabilized before supporting platinum, the firing is stabilized at a temperature at which zirconium oxide having a tetragonal crystal structure can be obtained. A preferable range of the firing temperature is 550 to 800 ° C, and a more preferable range is 600 to 750 ° C. The preferred firing time is 0.5 to 10 hours. After the sintering is stabilized, platinum is contained, and the temperature is further increased to 300 to 700 ° C, preferably 50 to 700 ° C.
The catalyst may be activated by firing at 0 ° C. to 600 ° C.

The catalyst of the present invention can be used by the above stabilization treatment. However, in order to stabilize the catalytic activity, it is preferable to carry out a pretreatment before use in the desulfurization isomerization reaction. The pretreatment consists of drying the catalyst at a temperature of 100-500 ° C. for 1-5 hours, followed by a reduction treatment at a temperature of 100-400 ° C.

The obtained catalyst of the present invention may contain, if necessary, alumina, silica alumina, silica, boria, titania,
Activated carbon and the like can be mixed and used.

The shape of the catalyst is not particularly limited, and various shapes usually used for this type of catalyst, for example, a columnar shape obtained by tableting and extrusion, a four-leaf type, and the like can be adopted.

As the feedstock to be isomerized simultaneously with desulfurization using the catalyst of the present invention, light naphtha distilled from an atmospheric distillation unit for crude oil and hole naphtha distilled from an atmospheric distillation unit for crude oil are also used. Light hydrocarbon oil containing organic sulfur, such as light naphtha, or marlox naphtha obtained by applying marlox treatment to light naphtha, is suitable. Particularly preferred feedstocks have an ASTM distillation temperature of 2
Light naphtha at 5 to 130 ° C, preferably 25 to 110 ° C. Speaking of the content of organic sulfur, light naphtha of 700 ppm by mass or less, preferably 10 to 500 ppm by mass, more preferably about 10 to 200 ppm by mass can be suitably used. It goes without saying that a light hydrocarbon oil having a sulfur content of several ppm or less can be used as a raw material.

Typical examples of the organic sulfur compounds contained in light naphtha include 2-propanethiol (CH ₃ ) ₂ CH-SH, ethanethiol C ₂ H ₅ -SH as thiol compounds (R-SH). The sulfide compound (RS-
R) as methyl ethyl sulfide CH ₃ -SC
₂ H ₅ , ethyl isopropyl disulfide C ₂ H ₅ -SS-CH (C
H ₃ ) ₂ and the like. By using the catalyst of the present invention, desulfurization can be carried out by hydrocracking these sulfur compounds simultaneously with isomerization of the feedstock oil.

In order to maintain the catalytic activity for a longer period of time, the amount of aromatic, unsaturated hydrocarbon and higher hydrocarbon in light naphtha used should be smaller. The benzene content is 5 vol.% Or less, preferably 3 vol.% Or less, the naphthene content is 12 vol.% Or less, preferably 9 vol.% Or less, and the C ₇ compound is 15 vol.% Or less, preferably 10 vol.% Or less.

The reaction conditions for the desulfurization isomerization are as follows: reaction temperature: 140 to 400 ° C., preferably 160 to 30 ° C.
0 ° C, more preferably 180 ° C to 220 ° C Reaction pressure: 1.0 to 4.5MPa, preferably 1.4 to
3.5 MPa LHSV: 1.0 to 10 h ^-1 , preferably 1.0 to 5 h
^-1 H ₂ / Oil ratio: 1~3mol / mol, preferably 1.5 to 2.
It is 5 mol / mol. When the reaction temperature is lower than 140 ° C., the life of the catalyst is shortened. On the other hand, when the reaction temperature is higher than 400 ° C., the activity is reduced because the sulfate group, which is the active site, is reduced by hydrogen and eliminated as hydrogen sulfide. Other conditions, ie reaction pressure, LHSV,
The H ₂ / Oil ratio is almost the same as the condition of a conventional light hydrocarbon oil isomerization reaction.

The catalyst of the present invention can be used as a hydrodesulfurization isomerization catalyst in place of a conventional isomerization catalyst. That is, an organic sulfur compound in a light hydrocarbon oil is hydrodesulfurized and converted into hydrogen sulfide, and the sulfur content can be reduced to several ppm or less and at the same time can be directly isomerized to obtain a product oil having an improved octane number. Can be.

Hereinafter, the present invention will be described in more detail by way of examples. However, the present invention is not limited to these examples, and includes various modifications without departing from the spirit of the present invention.

[0034]

Examples 1 to 5 and Comparative Example 1 Production of Catalysts A to F The following catalysts A to F were produced. In the production of Catalysts A to C (Example) and Catalyst F (Comparative Example), an impregnation method was adopted. First, zirconium hydroxide containing a sulfate group was prepared as in (1) and (2) of Example 1. This was impregnated with an aqueous solution of chloroplatinic acid, dried and fired.
In producing catalysts D and E (Examples), a kneading method was employed, and zirconium hydroxide was prepared and used as in (1) of Example 1.

[0035] Example 1: Dissolve 1000g of catalyst A (1) Zr (OH) 4 Preparation commercial zirconium oxychloride ZrOCl ₂ · 8H ₂ O in distilled water 4L, while stirring, 25% aqueous ammonia thereto NH ₃ aq. Was added dropwise to precipitate zirconium hydroxide Zr (OH) ₄ . PH of aqueous solution
Was adjusted to 9.0, and the precipitated zirconium hydroxide was separated by filtration. After filtration, wash well with distilled water, dry at 110 ° C. for 24 hours, and add zirconium hydroxide 4
90 g were obtained. (2) Preparation of SO ₄ / Zr (OH) ₄ 400 g of zirconium hydroxide prepared from zirconium oxychloride as described above was mixed with 4000 g of 1N sulfuric acid.
And stirred for 30 minutes. After stirring, the mixture was filtered and the solid was dried at 110 ° C. for 24 hours to obtain 452 g of sulfated zirconium hydroxide SO ₄ / Zr (OH) ₄ . (3) Preparation of Pt / SO ₄ / ZrO _{2 In} an aqueous solution in which 0.47 g of chloroplatinic acid H ₂ PtCl ₆ .xH ₂ O was dissolved, 19 g of the sulfate-containing zirconium hydroxide obtained in (2) was added. And impregnated with Pt salt. 1
After drying at 10 ° C all day and night, place in a muffle furnace for 600
Calcination for 3 hours at ℃, Pt-supported sulfate-containing zirconia Pt
/ SO ₄ / ZrO ₂ 13.5 g was obtained.

Example 2: Catalyst B Sulfate prepared by the preparation method described in Examples 1 (1) and (2) in an aqueous solution in which 2.65 g of chloroplatinic acid H ₂ PtCl ₆ .xH ₂ O is dissolved. Containing zirconium hydroxide 2
0 g was charged and impregnated with Pt salt. Thereafter, drying and firing were carried out in the same manner as in Example 1 to obtain 14 g of Pt-supported sulfate-containing zirconia Pt / SO ₄ / ZrO ₂ .

Example 3: Catalyst C 20 g of sulfate-containing zirconium hydroxide prepared by the preparation method described in Examples 1 (1) and (2) was heated in a muffle furnace at 600 ° C. for 3 hours. The sintering was stabilized to obtain 15 g of sulfate group-containing zirconia. 15 g of this sulfate-containing zirconia was added to an aqueous solution in which 0.36 g of chloroplatinic acid H ₂ PtCl ₆ .xH ₂ O was dissolved.
t impregnated. After drying at 110 ° C. for 24 hours, it was baked in a muffle furnace at 550 ° C. for 2 hours to obtain 13 g of Pt / SO ₄ / ZrO ₂ containing Pt-supported sulfate group.

Example 4: Catalyst D 3.1 g of commercially available ammonium sulfate was added to 22 g of zirconium hydroxide prepared by the preparation method shown in Example 1 (1), and water was added thereto using a kneader equipped with stirring blades. Kneaded for 1 hour. The obtained sulfate-containing zirconium hydroxide was dried at 110 ° C. for 24 hours, and then placed in a muffle furnace for 600 hours.
C. for 3 hours to stabilize the calcination, thereby obtaining 16 g of sulfate group-containing zirconia. Chloroplatinic acid H ₂ PtCl ₆ .xH ₂ O
Then, 16 g of this sulfate-containing zirconia was added to an aqueous solution in which 3.30 g of the above was dissolved to impregnate Pt. After drying at 110 ° C. for one day and night, it was calcined in a muffle furnace at 550 ° C. for 2 hours, and zirconia containing Pt-supported sulfate group Pt / SO ₄ /
14 g of ZrO ₂ were obtained.

Example 5: Catalyst E Hydroxide prepared by the preparation method described in Example 1 (1)
To 35 g of zirconium, 5.0 g of commercially available ammonium sulfate
And further add chloroplatinic acid H_TwoPtCl₆・ XH _TwoO's
0.93 g was added, and water was added using a kneader equipped with stirring blades.
While kneading for 1 hour. The obtained sulfated hydroxyl-containing diamine
After drying the ruconium at 110 ° C all day and night, the muffle furnace
And baked at 600 ° C for 3 hours.
Luconia Pt / SO_Four/ ZrO_Two25 g were obtained.

Comparative Example 1: Catalyst F 1.5 g of chloroplatinic acid hexahydrate H ₂ PtCl ₆ .xH ₂ O
Was dissolved in 168 g of sulfate-containing zirconium hydroxide prepared by the preparation method described in Examples 1 (1) and (2), and impregnated with a Pt salt. Thereafter, drying and firing were carried out in the same manner as in Example 1 to obtain 119 g of Pt-supported sulfate-containing zirconia Pt / SO ₄ / ZrO ₂ .

The results of the physical properties tests of Catalysts A to F are summarized in Table 1. Table 1 Physical Properties of Catalyst (Part 1) Catalyst A Catalyst B Catalyst C Catalyst D Structure of Catalyst Pt / SO ₄ / ZrO ₂ Pt / SO ₄ / ZrO ₂ Pt / SO ₄ / ZrO ₂ Pt / SO ₄ / ZrO ₂ Firing conditions 600 ° C × 3h 600 ° C × 3h 600 ° C × 3h 600 ° C × 3h Specific surface area (m ² / g) 121 118 128 132 Sulfur content (% by mass) 1.72 1.64 2.01 1.73 Metal element analysis value (% by mass) Pt 0.92 4.50 0.85 7.45 ZrO ₂ crystal structure ratio Monoclinic / tetragonal 3.5 / 96.5 3.7 / 96.3 4.1 / 95.9 4.3 / 95.7 Table 1 Physical Properties of Catalyst (Part 2) Catalyst E Catalyst F Catalyst Configuration Pt / SO ₄ / ZrO ₂ Pt / SO ₄ / ZrO ₂ firing conditions 600 ℃ × 3h 600 ℃ × 3h Specific surface area (m ² / g) 119 145 Sulfur content (% by mass) 1.52 1.64 Metal element analysis value (% by mass) Pt 0.81 0.35 ZrO ₂ crystal structure ratio Monoclinic Crystal / tetragonal 4.5 / 95.5 4.6 / 95.4

For the measurement of the specific surface area, a high-precision fully automatic gas adsorption apparatus "BELSORP28" manufactured by Bell Japan Co., Ltd. was used. The amount of sulfur is "SC-132" manufactured by LECO.
It was measured using a sulfur analyzer.

[0043]

[Example of use of catalyst] Desulfurization isomerization reaction of light hydrocarbon oil Light hydrocarbon oil was subjected to desulfurization isomerization using a fixed bed flow reactor having a catalyst filling capacity of 3 ml, and catalysts A to F were evaluated. The reaction conditions are as follows: Reaction pressure: 1.47 MPa Reaction temperature: 200 ° C. LHSV: 5 h ⁻¹ H ₂ / Oil ratio: 2 mol / mol Raw material: organic sulfur compound ((n-C ₃ H ₇ ) ₂ S ₂ ) Added n-pentane (300 ppm by mass of sulfur) Table 2 shows the isomerization ratio of n-pentane.

Here, the “isomerization ratio” is defined by the following equation. Isomerization rate (%) = (% by weight of iC ₅ in product oil) / (total of weight% of all C ₅ compounds in product oil) × 100

Table 2 Isomerization of n-pentane with added organic sulfur compound Reaction temperature: 200 ° C. Reaction pressure: 1.47 MPa LHSV: 5 / h H ₂ / Oil: 2 mol / mol Raw material: nC ₅ + (nC ₃ H ₇ ) ₂ S ₂ (S = 300 ppm ) Catalyst Reaction time (h) C5 isomerization rate (%) Catalyst A: Pt / SO ₄ / ZrO ₂ Pt: 0.92 mass% 2.8 57 4.7 626 5.560 Catalyst B: Pt / SO ₄ / ZrO ₂ Pt: 4.50% by mass 2.1 69 4.9 70 6.9 69 Catalyst C: Pt / SO ₄ / ZrO ₂ Pt: 0.85% by mass 2.9 55 5 .2 59 7.0 59 Catalyst D: Pt / SO ₄ / ZrO ₂ Pt: 7.45% by mass 3.1 64 4.9 65 6.9 63 Catalyst E: Pt / SO ₄ / ZrO ₂ Pt: 0.81% by mass 2 9.9 55 4.8 59 6.9 58 Catalyst F: Pt / SO ₄ / ZrO ₂ Pt: 0.35% by mass 2.1 22 4.2 9 5.3 3

When the catalysts A to E described in Examples 1 to 5 were used, the concentration of hydrogen sulfide at the outlet was about 150 ppm by volume.
Most of the 300 mass ppm organic sulfur compound contained in the raw material was hydrogenated and converted to hydrogen sulfide.
That is, in the catalysts A to E, not only isomerization of n-pentane, but also desulfurization of the organic sulfur compound is performed at the same time due to an increase in the amount of platinum whose sulfur resistance has been increased due to the lack of electrons due to the sulfate group. Was.

On the other hand, when the catalyst F of the comparative example was used,
The isomerization rate decreased over time, and the concentration of hydrogen sulfide at the outlet was about 30 ppm by volume, indicating that most of the organic sulfur compounds in the raw material were not converted to hydrogen sulfide. That is, in the catalyst F, since the amount of platinum having sulfur resistance is small,
Poisoned by organic sulfur compounds, the activity decreased.

[0048]

The catalyst of the present invention not only has high activity as a light hydrocarbon oil isomerization reaction catalyst, but also has sulfur resistance and hydrodesulfurizes organic sulfur compounds under isomerization reaction conditions. Can be. For this reason, in the isomerization of the light hydrocarbon oil containing the organic sulfur compound, it is not necessary to perform the desulfurization treatment which is an indispensable pretreatment in the prior art. Specifically, the isomerization process can be completed simply by filling the catalyst into a conventional fixed-bed catalytic reactor for isomerization and allowing the light hydrocarbon oil containing the organic sulfur compound to flow with hydrogen. Can be. Therefore, according to the present invention, hydrodesulfurization isomerization of a light hydrocarbon oil can be carried out at a reduced running cost using equipment simpler than conventional equipment.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuhiko Hagiwara 1134-2 Gongendo, Satte City, Saitama Prefecture Cosmo Oil Co., Ltd. (72) Inventor Atsushi Oshio 1134-2 Gongendo, Satte City, Saitama Cosmo Oil R & D Center Co., Ltd.

Claims (5)

[Claims] 1. A carrier made of a zirconium oxide or hydroxide containing a sulfate group in a sulfur content of 1 to 3% by mass and 0.5 to 10% by mass of platinum.
A catalyst for hydrodesulfurization isomerization of light hydrocarbon oils, which is calcined and stabilized at a temperature of 550 to 800 ° C and has a specific surface area of 50 to 150 m ² / g. 2. The method for producing a catalyst for hydrodesulfurization isomerization according to claim 1, wherein zirconium hydroxide is treated with a treating agent that gives a sulfate group thereto, and then impregnated with a platinum compound. A production method comprising firing at a temperature of 550 to 800 ° C. 3. The method for producing a catalyst for hydrodesulfurization isomerization according to claim 1, wherein the zirconium hydroxide is treated with a treating agent that gives a sulfate group to the zirconium hydroxide.
A production method comprising performing calcination at a temperature of 00C, then impregnating with a platinum compound, and calcination at a temperature of 300 to 700C. 4. The method for producing a catalyst for hydrodesulfurization isomerization according to claim 1, wherein zirconium hydroxide and a substance that gives a sulfate group are kneaded, and the mixture is kneaded at 550 to 800 ° C.
A firing method at a temperature of 300 ° C., followed by impregnation with a platinum compound, and firing at a temperature of 300 to 700 ° C. 5. A method for producing a catalyst for hydrodesulfurization isomerization according to claim 1, wherein zirconium hydroxide, a substance which gives a sulfate group thereto, and a platinum compound are kneaded, and 550-800. A production method comprising firing at a temperature of ° C.