JP2001181655A - Method for hydrodesulfurizing and isomerizing light hydrocarbon oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for hydrodesulfurizing and isomerizing a light hydrocarbon oil, by which the sulfur-containing light hydrocarbon oil can simultaneously be hydrodesulfurized and isomerized to obtain the isomerized gasoline having a low sulfur content and by which a catalyst enabling to simultaneously carry out an isomerization process and a desulfurization process having been essential as a pretreating process for the isomerization process can be provided to simplify necessary installations and lower the running cost. SOLUTION: This method for hydrodesulfurizing and isomerizing a light hydrocarbon oil is characterized by using a catalyst which is prepared by adding sulfate radical in an amount of 1 to 3 wt.% as a sulfur content and platinum in an amount of 0.5 to 10 wt.% to a carrier comprising zirconium oxide or hydroxide and then calcining and stabilizing the mixture at 550 to 800 deg.C and has a specific surface area of 50 to 150 m2/g, and bringing hydrogen and the light hydrocarbon oil having a sulfur content of <=700 weight ppm into contact with the prepared catalyst under conditions comprising a temperature of 160 to 240 deg.C, a pressure of 1.0 to 4.5 MPa, an LHSV of 1.0 to 10 h-1m, an H2/Oil ratio of 1 to 3 mol/mol to hydrodesulfurize and simultaneously isomerize the light hydrocarbon oil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention is capable of simultaneously achieving hydrodesulfurization and isomerization of a light hydrocarbon oil containing an organic sulfur compound, and can be carried out with simpler equipment than the prior art. The present invention relates to a process for the hydrodesulfurization of light hydrocarbon oils which is economical.

[0002]

2. Description of the Related Art Light hydrocarbon oil isomerization is a technique which has been widely used in the fields of petroleum refining and petrochemical industries. 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 currently practiced process, first, light naphtha is converted to Co-Mo / Al ₂
O ₃ was treated with hydrodesulfurization catalyst such as to convert the organic sulfur compounds to hydrogen sulfide, to get the desulfurized light naphtha having a reduced sulfur content less than several ppm by separating the hydrogen sulfide from the product oil Thereafter, a two-stage operation of using this as an isomerized feedstock 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 filled with a sulfur-resistant isomerization catalyst, and a light hydrocarbon oil containing an organic sulfur compound is used as a raw material for the isomerization. It is desirable that hydrodesulfurization and isomerization reactions can be performed 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 make use of the above-mentioned new knowledge obtained by the inventors and to economically desulfurize a light hydrocarbon oil containing an organic sulfur compound by using simple equipment and to obtain an isomer. And to provide a hydrodesulfurization isomerization method capable of simultaneously achieving the hydration.

[0008]

The method for hydrodesulfurizing and isomerizing a light hydrocarbon oil according to the present invention is characterized in that a carrier comprising zirconium oxide or hydroxide is converted to a sulfuric acid group having a sulfur content of 1 to 3 mass%. %, And 0.5-10% platinum.
And a light hydrocarbon oil having a sulfur content of 700 mass ppm or less and hydrogen on a catalyst having a specific surface area of 50 to 150 m ² / g. , Temperature: 160-240 ° C, pressure: 1.0-
4.5 MPa, LHSV: 1.0 to 10 h ^-1 , H ₂ / Oil
It is characterized by contacting under reaction conditions of a ratio of 1 to 3 mol / mol.

[0009]

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

The catalyst used in the hydrodesulfurization isomerization method of the present invention uses a zirconium oxide or hydroxide as a carrier as described above, and contains platinum in an amount of 0.5 to 10% by mass, preferably 0.1 to 10% by mass. 6 to 7% by mass, more preferably 0.7 to 7% by mass
5 mass% was carried. 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 sulfate groups does not reach 1% by mass as the sulfur content, the solid superacidity is weak because the acidity of the catalyst is low,
Insufficient activity as an isomerization catalyst. When the amount exceeds 3%, the zirconia surface is excessively covered with sulfate,
Since the active points are crushed by being laminated on the surface, 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 by 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 the 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 the zirconium oxide was determined by measuring the X-ray diffraction peak of the catalyst, and determining the 2θ = 28.2 (main peak of the monoclinic structure) peak and 2θ = 30 by CuKα radiation. 2 (main peak of the tetragonal structure) and the X-ray diffraction peak integrated intensity ratio. 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.

The catalyst used in the hydrodesulfurization isomerization method of the present invention is required to have a specific surface area measured by the BET method of 50 to 150 m ² / g after being calcined and stabilized at a predetermined temperature. is there. If the specific surface area is less than 50 m ² / g, the dispersibility of the supported platinum is poor, and the number of active sites for hydroisomerization is small. In addition, the crystal structure of zirconium oxide is not preferable because the ratio of monoclinic to tetragonal tends to be larger than 20/80. On the other hand, when the specific surface area exceeds 150 m ² / g, crystallization of the zirconium oxide does not progress and the ratio of the zirconium oxide tetragonal structure in the zirconium oxide is low, so that the activity of hydrodesulfurization isomerization is low.

The method for producing the catalyst used in the hydrodesulfurization isomerization method of the present invention is not particularly limited, and the method of giving a sulfate group and supporting platinum can be in any order. It is a manufacturing method as described in (1).

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.

In a third production method, a substance that gives a sulfate group to zirconium hydroxide is kneaded, calcined at a temperature of 550 ° C. to 800 ° C., and then impregnated with a platinum compound.
Next, 300 ° C to 700 ° C, preferably 500 ° C to 60 ° C.
Baking again at a temperature of 0 ° C.

In a fourth production method, a substance that gives a sulfate group, zirconium hydroxide, and a platinum compound are kneaded and mixed.
Firing at a temperature of 50C to 800C.

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 used in the hydrodesulfurization isomerization method of the present invention can be used by the above stabilization treatment.
In order to stabilize the catalytic activity, it is preferable to perform a pretreatment prior to use in the hydrodesulfurization 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 is optionally made of 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.

The raw material oil to be isomerized simultaneously with desulfurization using the above-mentioned catalyst according to the method of the present invention is light naphtha distilled from a crude oil distillation unit, and similarly a hole distilled from a crude oil distillation unit. Light hydrocarbon oils containing organic sulfur, such as light naphtha separated from naphtha, or marlox naphtha obtained by performing marlox treatment on light naphtha, are preferred. Particularly preferred feedstock is AS
TM distillation temperature is 25-130 ° C, preferably 25-11
Light naphtha at 0 ° C. Regarding the content of organic sulfur, 700 mass ppm or less, preferably 10 to 500 ppm
Light naphtha with a mass ppm of, more preferably, about 10 to 200 mass ppm 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 organic sulfur compounds contained in light naphtha include 2-propanethiol (CH ₃ ) ₂ CH-SH and 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. In the method of the present invention, desulfurization can be carried out by hydrocracking these sulfur compounds simultaneously with the isomerization of the feedstock.

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 preferably 5 vol.% Or less, preferably 3 vol.% Or less, the naphthene content is preferably 12 vol.% Or less, preferably 9 vol.% Or less, and the C ₇ compound is preferably 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 4.5 MPa, 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.
Activity decreases. Other conditions, namely reaction pressure,
The LHSV and the H ₂ / Oil ratio are almost the same as the conditions of a conventional light hydrocarbon oil isomerization reaction.

In carrying out the present invention, the above-mentioned catalyst is
As a hydrodesulfurization isomerization catalyst, it can be used 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 with reference to Examples. However, the present invention is not limited to these Examples, and includes various modifications without departing from the spirit of the present invention.

[0033]

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

[0034] Production 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.

Production Example 2: Catalyst B Sulfuric acid prepared by the preparation method described in Production Example 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. 20 g of root-containing zirconium hydroxide was added and impregnated with a Pt salt. Thereafter, drying and baking were performed in the same manner as in Production Example 1 to obtain 14 g of Pt-supported sulfate-containing zirconia Pt / SO ₄ / ZrO ₂ .

Production Example 3: Catalyst C 20 g of sulfate-containing zirconium hydroxide prepared by the preparation method described in Production Example 1 (1) and (2) is placed in a muffle furnace and heated to 600 ° C. for 3 hours. To stabilize, to obtain 15 g of sulfate group-containing zirconia. 15 g of this sulfate-containing zirconia was placed in an aqueous solution in which 0.36 g of chloroplatinic acid H ₂ PtCl ₆ .xH ₂ O was dissolved,
Impregnated with Pt. 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.

Production Example 4: Catalyst D Commercially available ammonium sulfate was added to 22 g of zirconium hydroxide prepared by the preparation method described in Production Example 1 (1).
g, and kneaded for 1 hour with a kneader equipped with stirring blades while adding water. The obtained sulfate-containing zirconium hydroxide was dried at 110 ° C. for 24 hours, and then placed in a muffle furnace for 6 hours.
Heating was performed at 00 ° C. for 3 hours to stabilize the calcination, thereby obtaining 16 g of sulfate group-containing zirconia. Chloroplatinic acid H ₂ PtCl ₆ xH
An aqueous solution prepared by dissolving ₂ O of 3.30 g, was impregnated with Pt to put this sulfate ion-containing zirconia 16g. 110 ° C
And then dried in a muffle furnace at 550 ° C for 2 days.
Calcination for Pt-supported sulfate group-containing zirconia Pt / SO
₄ / to obtain a ZrO ₂ 14 g.

Production Example 5: Catalyst E Commercially available ammonium sulfate 5.0 was added to 35 g of zirconium hydroxide prepared by the preparation method described in Production Example 1 (1).
Then, 0.93 g of chloroplatinic acid H ₂ PtCl ₆ .xH ₂ O was added, and the mixture was kneaded with a kneader equipped with stirring blades for 1 hour while adding water. The obtained sulfate-containing zirconium hydroxide was dried at 110 ° C. for 24 hours, then placed in a muffle furnace and calcined at 600 ° C. for 3 hours to obtain 25 g of Pt-supported sulfate-containing zirconia Pt / SO ₄ / ZrO ₂ .

Comparative Production 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 Production Example 1 (1) and (2), and impregnated with a Pt salt. Thereafter, drying and firing were performed in the same manner as in Production Example 1 to obtain 119 g of Pt-supported sulfate-containing zirconia Pt / SO ₄ / ZrO ₂ .

The results of the physical property 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 Nippon Bell Co., Ltd. was used. The amount of sulfur is "SC-132" manufactured by LECO.
It was measured using a sulfur analyzer.

[0042]

EXAMPLES Desulfurization isomerization reaction of light hydrocarbon oil Light 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 added with 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 catalysts A to E described in Catalyst Production Examples 1 to 5 were used, the concentration of hydrogen sulfide at the outlet was about 150 vol.
ppm, and most of the 300 mass ppm organic sulfur compounds contained in the raw material were 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 Comparative Production Example was used, the isomerization rate decreased with the passage of time, and the concentration of hydrogen sulfide at the outlet was about 30 ppm by volume. Not converted to hydrogen. That is, in the catalyst F, since the amount of platinum having sulfur resistance was small, the catalyst F was poisoned by the organic sulfur compound and the activity was reduced.

[0047]

The catalyst used in the hydrodesulfurization isomerization method of the present invention not only has high activity as a light hydrocarbon oil isomerization reaction catalyst, but also has sulfur resistance and can be used under isomerization reaction conditions. Organic sulfur compounds can also be hydrodesulfurized. 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 light hydrocarbon oils can be performed using equipment simpler than conventional equipment and at a reduced running cost.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuhiko Hagiwara 1134-2 Gondogendo, Satte City, Saitama Prefecture Cosmo Oil Co., Ltd. F-term in R & D Center Co., Ltd. (reference) 4G069 AA03 AA08 BA05A BA05B BB04A BB04B BB10A BB10B BC51A BC51B BC75A BC75B CC02 DA05 EC02X EC03X FA02 FB30 FC07 FC08 4H029 CA00 DA00

Claims (1)

[Claims] 1. A carrier made of a zirconium oxide or hydroxide contains a sulfate group in a sulfur content of 1 to 3% by mass and supports platinum in a range of 0.5 to 10% by mass,
A catalyst 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 is coated with a light hydrocarbon oil having a sulfur content of 700 mass ppm or less and hydrogen at a temperature of 140 to 140 ppm. 400 ° C., pressure: 1.0 to 4.5 MPa,
_{^{LHSV: 1.0~10h -1, H 2 /}} Oil ratio: 1~3mol /
A process for hydrodesulfurization isomerization of light hydrocarbon oils, which is carried out under a reaction condition of mol.