JPH09225304A - Catalyst for hydrogenation treatment of hydrocarbon oil and hydrogenation treatment of light oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a catalyst suitable for hydrogenation treatment of hydrocarbon oil, especially, a light oil fraction to reduce the content of an aromatic compd. and to hydrogenate the light oil fraction by using this catalyst. SOLUTION: This catalyst is based on alumina and obtained by supporting 0.1-8mass% (in terms of metal) of platinum on a carrier composed of a non- alumina type inorg. oxide or by supporting 0.1-2 mass % (in terms of oxide) of either one of an alkaline metal and an alkaline earth metal thereon in addition to 0.1-8mass% (in terms of metal) of platinum on a catalyst basis. This catalyst is used in the hydrogenation reaction of hydrocarbon oil to make it possible to reduce the content of an aromatic compd. in hydrocarbon oil. The reaction condition at a time of the hydrogenation treatment of light oil using this catalyst is set so that hydrogen partial pressure is 3-10MPa and temp. is 200-400 deg.C and liquid spatial velocity is 0.1-5.0hr<-1> to perform catalytic reaction of a light oil fraction containing an aromatic compd.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a catalyst used in a hydrogenation reaction of a hydrocarbon oil to reduce the aromatic compound content and the sulfur content of the hydrocarbon oil, and a gas oil hydrotreatment using the catalyst. More specifically, the present invention relates to a catalyst having high hydrogenation activity for aromatic compounds, particularly monocyclic aromatic compounds and high sulfur resistance, and also having high desulfurization performance, and a low sulfur content using the catalyst. And a low aromatics content gas oil blend base stock.

[0002]

2. Description of the Related Art A diesel engine, which is widely used as an internal combustion engine, has a straight-cut light oil fraction having a specific boiling range obtained by atmospheric distillation of crude oil, or a straight-cut light oil fraction obtained by subjecting a straight-cut light oil fraction to a hydrotreatment. A fuel oil is a gas oil consisting of a gas oil fraction, or a gas oil obtained by blending a gas oil fraction obtained from another source with a gas oil as a main base material. The diesel oil straight-cut fraction suitable for diesel engines contains only a limited amount of crude oil per unit amount of crude oil, and the available crude oil is becoming heavier year by year. Content tends to decrease. Therefore,
In order to secure the necessary amount of light oil fraction, heavy oil is also decomposed and converted into light oil base material. On the other hand, the demand for light oil tends to increase more and more due to factors such as an increase in demand for light oil with an increase in diesel engine vehicles, and it is expected that the supply amount of light oil will be significantly short in the near future.

One method of coping with the shortage of light oil fraction obtained from crude oil as straight run fraction and responding to the increasing demand for light oil is to increase the production amount of the blend base material blended with the straight run light oil fraction. is there. Therefore, a light cracking light oil (Light Cycle Oil) with a specific boiling range obtained from a catalytic cracker
, Hereinafter, abbreviated as LCO) has attracted attention as a feedstock for a new blend base material for light oil. that is,
Contrary to the light oil fraction, the LCO tends to be in excess due to the above-mentioned heavy crude oil, and from the balance of supply and demand of the fraction,
This is because it is a desirable fraction to be diverted to a blend base material.

However, since LCO contains a large amount of aromatic components, if LCO is blended with a straight-run light oil fraction in the same state, the content of aromatic compounds increases,
The cetane number of the blended light oil is lowered, and there is concern that the quality of the blended light oil will deteriorate. Further, since the content of the aromatic compound is high, it is feared that when the blended light oil is used as a fuel for a diesel engine, the amount of generated particulates remarkably increases. Particulates are air pollutants in the form of fine particles generated by incomplete combustion of some aromatic compounds. Emission of a large amount of particulates into the atmosphere poses a serious problem for environmental protection. Will cause it. In addition, LCO has a unique coloring, and if this is used as it is as a blending base of light oil, the quality of the light oil of the product in terms of hue becomes a problem.

Therefore, in order to use LCO as a blend base material, attempts have been made to reduce the content of aromatic compounds in LCO by subjecting LCO to catalytic hydrogenation treatment.

[0006]

However, when the LCO is hydrotreated by the conventional method, the following problems occur. First, the hydrogenation reaction rate of an aromatic compound is slower as the number of aromatic compound rings decreases in the order of 3 rings> 2 rings> 1 ring. Furthermore, in the process of sequentially hydrogenating a polycyclic aromatic compound to convert it to the final naphthenes, the reaction of hydrogenating a 1-ring aromatic compound to convert it to a naphthene becomes a rate-determining step.
A decrease in aromatic compounds having more than one ring leads to an increase in aromatic compounds having one ring, which results in that the content of all aromatic compounds in the LCO does not decrease so much. Further, in terms of reaction equilibrium, the higher the pressure, the more advantageous the hydrogenation reaction becomes. Therefore, the lower the hydrogen partial pressure condition, the more difficult the hydrogenation reaction proceeds. This restriction on the reaction equilibrium extends to the hydrogen pressure conditions for the usual hydrodesulfurization reaction of light oil fractions. Therefore, when performing hydrodesulfurization of gas oil fractions at a relatively low hydrogen partial pressure, it is possible to perform desulfurization by hydrogenation reaction or hydrocracking reaction of sulfur compounds by using a catalyst currently generally used. However, it is difficult to hydrogenate aromatic compounds.

Secondly, the sulfur compound contained in the LCO in a relatively large amount, or hydrogen sulfide produced by the hydrogenation of the sulfur compound, inhibits the hydrogenation reaction of the aromatic compound and also causes a catalyst failure. The poisoning of the active sites of the above causes the deterioration of the activity. Moreover, although LCO normally obtained at refineries has a lower total sulfur compound content than the straight-run light oil fraction, it often contains a sulfur content at a content rate higher than the regulated value which will be strengthened in the future. For example, since 1997, the sulfur content of light oil has been restricted to 0.05% by mass or less in Japan. Therefore, depending on the properties of the LCO,
Alternatively, depending on the specifications required for the produced oil, it is necessary to further reduce the sulfur content in the produced oil to the level required by the specifications. In addition, LCO is a high-boiling, hardly desulfurizable sulfur compound (for example, 4,6-dimethyldibenzothiophene).
Due to its high content of L, the desulfurization treatment of LCO requires deep desulfurization under conditions severer than those of straight-run gas oil fractions. Therefore, the catalyst is required to have an efficient and effective hydrogenation (desulfurization) performance capable of hydrotreating and removing the hardly desulfurizable sulfur compound.

Therefore, the condition of the LCO hydrotreating catalyst, which is necessary in order to reduce the aromatic compounds by hydrotreating the LCO and to use the LCO as a blend base material of the light oil fraction, is 1 ring. It has a high hydrogenation activity for aromatic compounds and a high sulfur resistance, and further has a high desulfurization performance capable of removing a difficult desulfurization sulfur compound by hydrogenation.

On the other hand, the catalysts that have hitherto been tried as catalysts for hydrotreating LCO are roughly classified into two types. One of them is a hydrotreating catalyst used for hydrotreating light oil, and a precious metal or the like is used as an active metal species. The other one is a Group VIA metal-Group VIII metal-based catalyst of the periodic table, for example, a CoMo-based or NiMo-based hydrodesulfurization catalyst using an alumina carrier.

However, since the conventional hydrotreating catalyst contains a metal species having poor sulfur resistance such as nickel and palladium as an active component of the catalyst, the sulfur compound content in the feed oil is small. It works effectively only in a low sulfur atmosphere of ppm or less. Therefore, it is technically difficult to use a conventional hydrotreating catalyst for hydrotreating an LCO having a higher sulfur compound content.

On the other hand, the above-mentioned hydrodesulfurization catalyst is a typical hydrodesulfurization catalyst used in a petroleum refining process, and since it is originally intended for hydrodesulfurization, it has a sulfur resistance. Although sufficient, there are some areas where the hydrogenation performance of the 1-ring aromatic compound is insufficient.

Therefore, in order to use a hydrodesulfurization catalyst as a catalyst for hydrotreating LCO and hydrogenate a 1-ring aromatic compound to convert it to naphthenes, under a high hydrogen partial pressure of 10 MPa or more. Further, depending on other conditions such as the properties of the raw material oil and the reaction temperature, it is necessary to carry out the hydrotreatment under a higher pressure condition, which increases equipment costs and operating costs. When a desulfurization catalyst is used, the reaction rate can be increased by increasing the reaction temperature instead of increasing the hydrogen partial pressure, and the conversion of the 1-ring aromatic compound can be promoted. This is not only disadvantageous in terms of reaction equilibrium to the hydrogenation reaction, which is an exothermic reaction, but also side reactions such as decomposition reaction and polycondensation reaction significantly progress, so that the yield of hydrogenation product decreases and the economy Not relevant. Further, since the reaction is carried out at a high temperature, the problem of the hue of the produced oil is not improved, and further, the equipment cost and the operating cost of the apparatus increase.

As described above, the conventional catalyst does not satisfy the requirement of a catalyst that has both high hydrogenation activity for a 1-ring aromatic compound and sulfur resistance, and has desulfurization performance. Was not suitable for the treatment for reducing the aromatic compound content of LCO. Then, the object of the present invention is, firstly, a hydrocarbon oil,
In particular, it is to provide a catalyst suitable for reducing the aromatic compound content by hydrotreating a gas oil fraction.
To provide a method for hydrotreating a gas oil fraction using the catalyst.

[0014]

[Means for Solving the Problems] In order to solve the above-mentioned object, the present inventors have proposed that platinum, or an alkali metal or alkaline earth in addition to platinum, is added to a carrier composed of an inorganic oxide containing alumina as a main component. As a result of repeated experiments of preparing a new catalyst supporting a metal group and carrying out a hydrogenation reaction of an aromatic compound, the new catalyst shows that the hydrogen partial pressure and reaction temperature, etc. are almost the same as those in the conventional hydrotreatment. Under the conditions of, NiM
The inventors have found that they have higher hydrogenation activity for aromatic compounds, particularly monocyclic aromatic compounds, as compared with conventional catalysts for desulfurization such as o-based and CoMo-based catalysts, and have completed the present invention.

That is, the catalyst according to the present invention comprises a carrier composed of an inorganic oxide containing alumina as a main component and containing a non-alumina system, and 0.1 to 8% by mass (metal conversion) of platinum, based on the catalyst, or Hydrogenation of hydrocarbon oil carrying 0.1 to 2% by mass (as metal) of platinum and 0.1 to 2% by mass (as oxide) of either alkali metal or alkaline earth metal. It is a processing catalyst.

The catalyst of the present invention is suitable for hydrotreating hydrocarbon oils, particularly gas oil fractions, for example, hydrocracking of catalytically cracked gas oil, straight run gas oil, pyrolysis gas oil, hydrotreated gas oil, desulfurized gas oil and the like. ing. When hydrotreating a feedstock using the catalyst of the present invention, desirable properties as a feedstock for exerting catalytic performance have a boiling point range of 150 to 400 ° C, preferably 160 to 380 ° C, more preferably 170. ~ 350 ° C
The lower the sulfur content is, the more preferable it is.
m or less, preferably 500 mass ppm or less. Also,
The content of the aromatic compound is not particularly limited, but the content is preferably 5 to 90% by volume, more preferably 5 to 75% by volume.

The carrier of the catalyst of the present invention contains alumina as a main component, and further contains an inorganic oxide of a type other than alumina. As the main component of the carrier, various kinds of alumina such as α-alumina, β-alumina, γ-alumina and δ-alumina can be used, but it is preferably porous and has a high specific surface area. Alumina, more preferably γ-alumina.

On the other hand, an inorganic oxide of a type other than alumina mixed with alumina (hereinafter referred to as carrier subcomponent) is
The first type group includes, for example, silica, boria, titania, zirconia, magnesia, hafnia, ceria, yttria, niobia, etc., which are mixed alone with alumina, or a combination of two or more carrier subcomponents. Can be mixed with alumina. Of these first type carrier subcomponents, preferred are silica, boria, silica-alumina, silica-zirconia, silica-boria.

The second type of carrier subcomponent is a crystalline inorganic oxide such as zeolite or molecular sieve, or a clay mineral such as montmorillonite, kaolin, bentonite or saponite, which may be used alone or A combination of two or more carrier subcomponents can be mixed with the alumina.

Further, the third type of carrier subcomponent is an inorganic oxide obtained by activating a specific metal oxide such as zirconia or titania with sulfate ion, for example, SO ₄ / ZrO ₂ , S.
O ₄ / TiO _{2 and the} like, which can be mixed with alumina alone or in combination of two or more carrier subcomponents. Further, when two or more kinds of carrier subcomponents are mixed with alumina, they can be arbitrarily selected and mixed from the group of the first to third kinds of carrier subcomponents.

The content of the carrier subcomponent in the carrier when the carrier subcomponents are mixed with alumina alone or in combination of two or more kinds is 5 in terms of oxide based on the mass of the carrier.
-50 mass%, preferably 10-40 mass%. The mixing method of mixing the alumina and the carrier subcomponents is not particularly limited as long as the respective components are uniformly and uniformly mixed as a whole, and a generally used mixing method, for example, a chemical mixing method. Alternatively, a method called a physical mixing method can be used. That is, in the chemical mixing method, precursors of oxides of respective components, for example, gel, sol, hydroxide, etc. are mixed, and in the physical mixing method, oxides of respective components are mixed in a granular or powder form. To do.

The specific surface area, pore volume and average pore diameter of the carrier composed of the above alumina and carrier subcomponents are not particularly limited, but are excellent in sulfur resistance and hydrogenated to hydrocarbon oil. In order to obtain a catalyst having enhanced activity and desulfurization activity, the specific surface area is 200 m ² / g or more, more preferably 250 m ² / g or more, and the pore volume is 0.4 to
It is in the range of 1.2 ml / g and the average pore size is 50 to 10
It is preferably in the range of 0 °. In the catalyst of the present invention,
The shapes of the carrier and the catalyst are not particularly limited, and various known shapes which have been commercially available or reported so far may be used, and for example, a cylindrical shape, a four-lobed shape and the like can be used. The size of the catalyst is practically 1/10 to 1 /
22 inches is suitable. In addition, the timing of molding is not particularly limited as long as a predetermined catalyst shape can be obtained, and before molding the active ingredient, that is, at the stage of the carrier,
Then, the active ingredient may be supported, or the active ingredient may be supported on a granular or powdery carrier and then molded as a catalyst.

The active ingredient supported on the carrier is a platinum compound or a combination of a platinum compound and one of an alkali metal and an alkaline earth metal (hereinafter referred to as an active subcomponent).

Specific examples of the platinum compound include metal chlorides, chlorides, nitrates, sulfates, acetates, phosphates and organic acid salts, preferably metal chlorides, chlorides and nitrates. . These compounds can be used alone or in combination of two or more kinds.

The alkali metal and alkaline earth metal used as the active subcomponent are alkali metals such as potassium, lithium and calcium, alkaline earth metals and their compounds, and the active subcomponent alone or More than one type of active subcomponent can be included at the same time. Specific examples of the alkali metal and alkaline earth metal compounds include alkali metal salts or alkaline earth metal salts of the above platinum compounds, nitrates, halides, halogenates, sulfates, carbonates, etc., and preferred. Are alkali metal salts or alkaline earth metal salts, nitrates, chlorides and carbonates of platinum compounds. In addition, these compounds alone,
Alternatively, two or more kinds can be used in combination.

Of these active ingredients, the platinum content is 0.1 to 8 in terms of metal, based on the mass of the catalyst.
It is mass%, preferably 0.5 to 5 mass%. Platinum
If it is less than 0.1% by mass, sufficient active sites attributed to platinum cannot be obtained, and if it exceeds 8% by mass, not only the dispersibility of the active metal deteriorates due to aggregation of the platinum compound, but also efficient dispersion. Since the limit of the active metal content to be exceeded is exceeded, the cost becomes high. Furthermore, when the above-mentioned active subcomponents are also contained in addition to platinum, the content of these active subcomponents is 0.1 to 2% by mass in terms of oxide, based on the mass of the catalyst. is there. In general, many catalytic reactions including the hydrogenation reaction of aromatic compounds are greatly promoted by the acid sites present on the catalyst or the carrier. This is important for promoting the hydrogenation reaction of the aromatic compound even in the carrier used in the present invention, which is composed of an inorganic oxide containing alumina as a main component and containing a non-alumina system.
However, when the strength of the acid is too strong, side reactions such as decomposition reaction and isomerization reaction are excessively promoted rather than hydrogenation reaction of the aromatic compound, which is not preferable. Therefore, in order to proceed the hydrogenation reaction of the aromatic compound with high selectivity,
It is very important to control the acid strength of the support or catalyst. In the present invention, the addition of an active subcomponent, that is, an alkali metal or an alkaline earth metal is intended to control the acid point of the catalyst to an appropriate strength for the hydrogenation reaction of an aromatic compound. The content of the active subcomponent is 0.
If it is less than 1% by mass, it is not sufficient to exert the effect caused by these metals, and if it exceeds 2% by mass, the platinum metal and the reaction active sites present on the catalyst carrier are also covered, and the catalyst No improvement in activity can be seen.

The catalyst according to the present invention can be prepared by a known catalyst preparation method. As a typical method,
An impregnation method in which the carrier is impregnated with a solution prepared by dissolving the above-mentioned active ingredient in a solvent such as acid, water, alcohol or the like to carry the active ingredient onto the above-mentioned carrier once or more. . For example, when an acidic solvent such as hydrochloric acid, nitric acid or sulfuric acid is used as the solvent, the acid concentration is such that the active ingredient is sufficiently dissolved, and the acid erodes the surface of the carrier, resulting in the surface area and pore volume of the carrier. It is preferable to dilute to an acid concentration that does not significantly change the physical properties such as. The conditions for impregnating the carrier in the impregnating solution in which the active ingredient is dissolved are not particularly limited as long as a predetermined amount of the active ingredient is supported in a predetermined metal distribution. For example, when the temperature condition of the impregnating liquid is taken as an example, the temperature is from 10 ° C to 100 ° C.
The boiling point of the impregnating liquid, preferably 1
The temperature is in the range of 5 to 60 ° C., more preferably 15 to 40 ° C., and may actually be room temperature. The time for contacting the impregnating liquid with the carrier is not particularly limited as long as the metal distribution reaches a predetermined distribution, but usually the impregnation can be carried out for 15 to 5 hours. During the impregnation step, the impregnating liquid and the carrier may be left in contact with each other, but the impregnating liquid and the carrier may be stirred together to make the amount of the active ingredient supported evenly between the carriers. Preferably. Further, after the impregnation step, in order to fix the impregnated active ingredient to the carrier, it is preferable to impregnate the carrier with the impregnating liquid, and then to perform drying and baking treatment. The method for drying the catalyst is not particularly limited as long as the entire catalyst is uniformly dried, and various drying methods such as air drying, hot air drying, heat drying and freeze drying can be adopted. Usually, 10-100 in terms of efficiency and simplicity
Air drying with dry air or dry nitrogen at 15 ° C, preferably 15 to 60 ° C is good. If it is burnt for too long or at a high temperature, the active ingredients carried will aggregate, the carrier will sinter, or a phase change will occur, resulting in a large change in shape, physical properties, and chemical properties. May occur, so it is usually 350 to 600 ° C., preferably 400 to 600 ° C.
At a temperature in the range of 550 ° C. for 1 to 10 hours, preferably 2
Bake for ~ 5 hours. Further, the atmosphere during firing is not particularly limited as long as the atmosphere around the catalyst is not filled with the gas generated during firing, under the flow of an inert gas or air,
Usually, it is fired under the flow of air. When the catalyst is prepared by the impregnation method, when the impregnation treatment is performed a plurality of times, the drying and firing treatment may be performed for each impregnation treatment. Also, if the active subcomponent is contained, the timing of impregnating the active subcomponent is not limited, and it may be impregnated before or after the impregnation with the platinum compound, or may be impregnated with the platinum compound at the same time. Further, as another supporting method, a kneading method in which a part or all of the active ingredient is mixed with a carrier material before being molded as a carrier and integrally molded, and further, a coprecipitation method and the like can be mentioned.

In the catalyst according to the present invention prepared by the above-mentioned catalyst preparation method, the specific surface area, pore volume and average pore diameter are not particularly limited as long as the function as a catalyst is exhibited. However, like the above-mentioned carrier, the specific surface area is preferably 200 m ² / g or more, and more preferably 250 m ² / g or more in order to enhance the hydrogenation activity and desulfurization activity for hydrocarbon oil. The pore volume is preferably in the range of 0.4 to 1.2 ml / g,
More preferably, it is desirable to be in the range of 0.5 to 0.9 ml / g. The average pore diameter is preferably in the range of 50 to 100Å, more preferably in the range of 60 to 90Å. If the average pore size is less than 50Å, not only the mechanical strength is insufficient, but also the reactants are less likely to diffuse into the pores, so the hydrogenation reaction of aromatic compounds and refractory sulfur compounds is less efficient. Will not progress. On the other hand, if it is greater than 100Å, the diffusivity in the pores is good, but the surface area in the pores is reduced, so that the effective specific surface area of the catalyst is reduced and the activity is lowered. Further, in order to increase the effective number of pores satisfying the above-mentioned pore conditions, the pore diameter distribution of the catalyst (that is, the proportion of pores having an average pore diameter of ± 15Å) is 70% or more, preferably Is 80% or more.

When the gas oil is hydrotreated using the catalyst according to the present invention, the hydrogen partial pressure is usually in the range of 3 to 10 MPa, preferably 3 to 7 MPa, usually 200 to 4
Temperature in the range of 00 ° C, preferably 250 to 370 ° C, and usually 0.1 to 5.0 hr ^-1 , more preferably 0.5.
The catalyst and the feedstock are brought into contact with each other under the condition of the liquid hourly space velocity in the range of to 4.0 hr ⁻¹ . During the hydrogenation reaction, as long as hydrogen is supplied to at least the amount consumed in the reaction, hydrogen / oil ratio is not particularly limited, usually, 100~1000m ³ / m ^3, preferably hydrogen 200~600m ³ / m ³ Supply hydrogen so that the oil / oil ratio is achieved. The higher the hydrogen partial pressure, the more advantageous in terms of reaction equilibrium, but the operating pressure of the reactor becomes higher, which necessitates a thicker wall, which increases equipment costs. In addition, the power of the compressor that supplies hydrogen gas increases and operating costs increase.
When the reaction temperature is higher than 400 ° C, the hydrogenation reaction becomes disadvantageous in terms of reaction equilibrium, the decomposition reaction and the isomerization reaction proceed excessively, and the yield of the produced oil decreases. Conversely, the reaction temperature is 200
If the temperature is lower than 0 ° C, the progress of the hydrogenation reaction will be delayed, and the yield of the produced oil will be similarly reduced. Liquid hourly space velocity is 5.0 hr
^{If it is} larger than ^-1 , the contact time between the catalyst and the feed oil is too short,
Since the hydrogenation reaction does not proceed sufficiently, the yield of product oil is reduced. On the other hand, if the liquid hourly space velocity is smaller than 0.1 hr ^-1 , it is not economical because the amount of the catalyst increases and the reactor containing the catalyst becomes large. To carry out catalytic hydrotreating of hydrocarbon oils, such as gas oil, on a commercial scale, a fixed bed, moving bed or fluidized bed catalyst bed of the catalyst according to the invention is formed in the reactor and the gas oil is placed in the reactor. Is introduced and the hydrogenation reaction is carried out under the conditions specified in the present invention. Most commonly, a fixed bed catalyst bed is formed in the reactor, hydrocarbon oil is introduced at the top of the reactor, the fixed bed is passed from top to bottom, and the product is discharged from the bottom of the reactor. I will let you. The catalyst according to the present invention can be used also when it is packed in a single reactor to carry out one-stage hydrotreatment, or when it is packed in several reactors to carry out multi-stage continuous hydrotreatment. Can also be used for In particular, when the feedstock oil is a relatively heavy hydrocarbon oil, it is preferable to carry out a multistage hydrotreatment.

[0030]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Example 1 A catalyst performance test was conducted to evaluate the performance of the catalyst according to the present invention. First, as shown in Table 1, silica gel and alumina gel (or sol) were prepared as carrier materials, mixed so as to be γ-alumina containing 10% by mass of silica based on the carrier, washed, dried, and then Diameter 1/16
After being formed into an inch-shaped column, it was baked at 500 ° C. to obtain a carrier having a specific surface area of 336 m ² / g, a pore volume of 0.83 ml / g and an average pore diameter of 75Å. Carrier obtained in an aqueous solution in which 1.0 g of chloroplatinic acid was dissolved in 31.7 g of water 37.
3 g was added, and the carrier was impregnated with the aqueous solution while stirring at room temperature for about 4 hours. Then, the carrier impregnated with the aqueous solution is air-dried at room temperature in a nitrogen stream, and then 500 times under air flow.
Calcination was performed at 4 ° C. for 4 hours. As a result, a prototype catalyst of Example 1 in which 1% by mass (metal conversion) of platinum was impregnated and supported was prepared. Next, the trial catalyst was filled in the reactor 12 of the high pressure flow reactor 10 of FIG. 1 to form the fixed bed catalyst layer 14, and pretreated under the following pretreatment conditions. Next, as shown in the flow chart of FIG. 1, a mixed fluid of the feed oil heated to the reaction temperature and the hydrogen-containing gas is introduced into the reactor 12 from the upper part of the reactor 12, and the hydrogenation reaction is performed under the following conditions. The mixed fluid of the produced oil and the gas produced was caused to flow out from the lower part of the reactor 12, and the produced oil was separated by the gas-liquid separator 16.
The raw material oil is 15% by weight of naphthalene and 85% by weight of decalin.
It was a mixed oil of.

[Table 1]

Reaction conditions Reaction temperature: 250 or 300 ° C. (depending on the number of days elapsed after the start of operation) Pressure (hydrogen partial pressure): 4.9 MPa Liquid hourly space velocity: 1.8 hr ^-1 hydrogen / oil ratio: 560 m ³ / m ³ Pretreatment condition pressure of catalyst (hydrogen partial pressure); 4.9 MPa atmosphere; temperature under hydrogen gas flow; step temperature increase, 1.5 at 150 ° C.
Maintained for hr, then maintained at 300 ° C for 2 hr

The reactor was operated at a reaction temperature of 250 ° C. until the number of days after the start of the reaction shown in Table 2 (6 days in Example 1) passed, and when the time passed, a sample of the produced oil was sampled and its properties were measured. analyzed. The results are as shown in Table 2. Then, the reactor was operated at a reaction temperature of 300 ° C. until the number of days elapsed after the start of the reaction shown in Table 2 (6 days in Example 1) to the number of days shown in Table 4 (13 days in Example 1), At that time, a sample of the produced oil was taken and its properties were analyzed. The results are as shown in Table 3.

[Table 2]

[Table 3]

The conversion rates in Tables 2 and 3 represent the conversion rates (%) of naphthalene calculated by the following formula. Conversion (%) = {(A−B) / A} × 100 Here, A is the mass% of naphthalene in the feed oil, and B is the mass% of naphthalene in the produced oil. Further, decalin, tetralin, and the like represent the composition ratio (mass%) of each component of the produced oil (excluding decalin in the raw material oil) obtained by converting naphthalene in the raw material oil by hydrogenation. In addition, "others" collectively indicates the composition ratio (mass%) of all components other than decalin, tetralin, and naphthalene.

In Tables 2 and 3, the higher the conversion of naphthalene, the lower the content of tetralin, and the higher the content of decalin, the higher the activity of the hydrogenation reaction of the polycyclic aromatic compound, especially It can be evaluated that the lower the content of tetralin, the higher the conversion rate of monocyclic aromatic compounds to saturated hydrocarbons, and the saturated carbonization of monocyclic aromatic compounds that controls the hydrogenation reaction of polycyclic aromatic compounds. It can be evaluated as a preferable catalyst that accelerates the hydrogenation reaction to hydrogen.

Examples 2 to 12 In the same manner as in Example 1, trial catalysts of Examples 2 to 12 as shown in Table 1 were prepared, and the same feed oil and the same catalyst pretreatment as those of Example 1 were prepared. Example 1 under the same conditions and the same reaction conditions
The performance tests of the catalysts of Examples 2 to 12 were conducted in the same manner as in. However, in the catalyst of Example 11, platinum and potassium were simultaneously impregnated and supported on the carrier shown in Table 1,
In the catalyst of No. 2, platinum and lithium were simultaneously impregnated and supported on the carrier shown in Table 1, and in the catalyst performance test of Example 12, the liquid hourly space velocity during operation at the reaction temperature of 250 ° C. was
Instead of 1.8 hr ⁻¹ of Example 1 to Example 11,
It was set to 1.3 hr ^-1 .

In the performance tests of the catalysts of Examples 2 to 12, the reaction was carried out at the reaction temperature of 250 ° C. until the elapsed days shown in Table 2 and then at the reaction temperature of 300 ° C. until the elapsed days shown in Table 3 passed. The reactor was operated at each temperature, and a sample of the produced oil was collected at the time when the elapsed days passed.
The properties of the product oil at the reaction temperature of 250 ° C. and the properties of the product oil at the reaction temperature of 300 ° C. are shown in Tables 2 and 3, respectively.

Comparative Example 1 Unlike the catalyst according to the present invention, as a carrier material for the catalyst,
Using γ-alumina simple substance containing no inorganic oxide, Table 1
The catalyst of Comparative Example 1 was prepared by carrying the active ingredient shown in 1 above, and hydrogenated in the same manner as in Example 1 under the same feed oil, the same pretreatment conditions, and the same reaction conditions as in Example 1.
In the performance test of the catalyst of Comparative Example 1, the reaction temperature was 250 ° C. until the elapsed days (5 days) shown in Table 2 passed, and then the elapsed days (12 days) shown in Table 3 passed 300 times.
The reaction apparatus was operated at the reaction temperature of 0 ° C., and a sample of the produced oil was collected when the elapsed days passed. 250
The properties of the product oil at the reaction temperature of 300C and the properties of the product oil at the reaction temperature of 300C are shown in Tables 2 and 3, respectively.

[0038] same carrier as in Comparative Example 2 Comparative Example 1, in terms of oxide, impregnated with 4 wt% of nickel and 20 wt% tungsten, by supporting, to prepare a catalyst of Comparative Example 2, pretreatment of the catalyst Under a mixed gas flow of hydrogen and hydrogen sulfide at 150 ° C. for 2 hours, 35 hours
Hydrogenation was carried out in the same manner as in Example 1 under the same reaction conditions as in Example 1 except that the sulfurization treatment was carried out at a pretreatment temperature by increasing the temperature by maintaining each step at 0 ° C. for 2 hours. Processed. In the performance test of the catalyst of Comparative Example 2, it took 25 days until the elapsed days (5 days) shown in Table 2 were elapsed.
At a reaction temperature of 0 ° C., then the number of days elapsed (12
Each of the reactors was operated at a reaction temperature of 300 ° C. until the lapse of days), and a sample of the produced oil was collected at the time when the elapsed days passed. The properties of the product oil at the reaction temperature of 250 ° C. and the properties of the product oil at the reaction temperature of 300 ° C. are shown in Tables 2 and 3, respectively.

As can be seen from Tables 2 and 3, the catalysts according to the present invention used in Examples 1 to 12 have the same hydrogen partial pressure and reaction temperature as in the conventional hydrotreatment,
At least one of the conversion rate of naphthalene and the conversion rate of a part of the aromatic compound is larger than that of the catalysts of Comparative Examples 1 and 2, and it can be evaluated that the catalyst is effective in reducing the aromatic compound.

Example 13 The same catalyst as in Example 2 was charged into the reactor 12 of the high pressure flow reactor 10 of FIG. 1 in the same manner as in Example 1 to form the fixed bed type catalyst layer 14, and After treatment under the same pretreatment conditions, hydrotreating was performed under the reaction conditions shown below, using a desulfurized gas oil having the properties described below as a feedstock. Raw oil type; Desulfurized light oil Specific gravity (15/4 ° C); 0.8454 Viscosity (@ 30 ° C); 5.971 mm ² / s Distillation properties; (Initial boiling point) is 201 ° C, (50%
Point) is 309 ° C., (end point) is 384 ° C. Sulfur content; 0.038 mass% nitrogen content; 0.011 mass% saturated hydrocarbon component; 72.2% by volume 1 ring aromatic; 21.9% by volume 2 ring Aromatic: 4.6% by volume Three-ring aromatics: 1.3% by volume Seybolt color: -16 or less

Reaction conditions Reaction temperature; 350 ° C. Pressure (hydrogen partial pressure); 4.9 MPa Liquid hourly space velocity; 1.5 hr ^-1 hydrogen / oil ratio; 560 m ³ / m ^{3 In} the catalyst performance test of Example 13, Table 4 The number of days elapsed,
That is, after 21 days had elapsed, a sample of the produced oil was collected and its properties were analyzed. The results are as shown in Table 4.

[Table 4]

In Table 4, a higher saturated hydrocarbon ratio means a catalyst that accelerates the hydrogenation reaction of the aromatic compound, and a higher Saebolt value decomposes and removes the coloring component. Can be evaluated.

Examples 14 to 20 As shown in Table 4, Examples 2, 5, 7, 8, 10, 11 were obtained.
And using any of the catalysts prepared in
Hydrotreating was carried out in the same manner as in Example 13 under the same feedstock oil and reaction conditions as in 3. However, liquid hourly space velocity in Example 20, instead of 1.5hr ^-1 Example 19 from Example 14, was 0.6hr ^-1. In the catalyst performance tests of Examples 14 to 20, at the time when the number of days elapsed shown in Table 4 had elapsed, the produced oil was collected and its properties were analyzed. The results are as shown in Table 4.

Comparative Example 3 Hydrotreating was performed in the same manner as in Example 13 except that the catalyst and the pretreatment conditions for the catalyst were the same as those in Comparative Example 1. In the performance test of the catalyst of Comparative Example 3, the number of elapsed days (2
After the lapse of 0 days), the produced oil was collected and analyzed for its properties. The results are as shown in Table 4.

Comparative Example 4 The hydrogenation treatment was carried out in the same manner as in Example 13 except that the catalyst and the pretreatment conditions for the catalyst were the same as those in Comparative Example 2. In the performance test of the catalyst of Comparative Example 4, the elapsed days (2
After the lapse of 0 days), the produced oil was collected and analyzed for its properties. The results are as shown in Table 4.

As can be seen from Table 4, in Examples 13 to 20 using the catalyst according to the present invention, as compared with Comparative Examples 3 and 4, the three-ring, two-ring and one-ring aromatics in the produced oil were compared. The compound content is low, and conversely the saturated hydrocarbon component content is high. This is because the catalyst according to the present invention has a hydrogenation reaction of an aromatic compound, particularly a hydrogenation of a one-ring aromatic compound, which has been difficult in the past, under substantially the same hydrogen partial pressure and reaction temperature as in the conventional hydrotreatment. It is shown to be effective for the reaction.
Further, as can be seen from Table 4, Example 13 to Example 20
The produced oil obtained in 1. has a lower sulfur content than the produced oil obtained in Comparative Example 3 and has an extremely low level. This shows that the catalyst according to the present invention can produce a product oil containing only a very small amount of sulfur by hydrotreating a feedstock oil having a sulfur content of about 0.04%, and has a high sulfur resistance and desulfurization. It shows that the performance is high. Table 4 also shows that the catalyst according to the present invention can significantly improve the Saybolt color.

Example 21 Using the same carrier as in Example 2, as shown in Table 5, a catalyst having a platinum loading of 0.1% by mass was prepared in the same manner as in Example 1, and a prototype of Example 21 was prepared. It was used as a catalyst. Then, Example 1
1 is filled in the reactor 12 of the high-pressure flow reactor 10 of FIG. 1 to form a fixed bed catalyst layer 14 and treated under the same pretreatment conditions as in Example 2, and then desulfurization having the properties described below. Using the treated LCO as a feed oil, hydrogenation treatment was performed under the reaction conditions shown below, and an evaluation test of the prototype catalyst of Example 21 was performed.

[Table 5]

Raw oil type; Desulfurized LCO specific gravity (15/4 ° C.); 0.9089 viscosity (@ 30 ° C.); 3.870 mm ² / s distillation property; (initial boiling point) is 177 ° C., (50%
Point) is 276 ° C., (end point) is 362 ° C. Sulfur content; 0.018 mass% nitrogen content; 0.031 mass% saturated hydrocarbon component; 30.9 vol% aromatic compound component; 69.1 vol%

Reaction conditions Reaction temperature; 350 ° C. pressure (hydrogen partial pressure); 4.9 MPa liquid hourly space velocity; 1.5 hr ^-1 hydrogen / oil ratio; 560 m ³ / m ³

In the catalyst performance test of Example 21, a sample of the produced oil was collected at the time when 14 to 17 days had elapsed after the start of the reaction, and its properties were analyzed. The results are as shown in Table 6. In Table 6, it means that the higher the dearomatization rate, the more the hydrogenation reaction of the aromatic compound proceeds, and the lower the content rate of the aromatic compound component in the produced oil. The dearomatization rate shown in Table 6 is represented by the reduction rate (%) of the aromatic compound component calculated by the following formula. Dearomatization rate (%) = {(A−B) / A} × 100 where A is the volume% of the aromatic compound in the feed oil, and B is the volume% of the aromatic compound in the produced oil. Is.

[Table 6]

Examples 22 to 26 In Examples 22 to 26, the loading amount of platinum was 0.5% by mass, respectively, as shown in Table 5, unlike Example 21.
1.0 wt%, 2.1 wt%, 4.8 wt% and 7.1
%, Respectively, to prepare trial catalysts of Examples 22 to 25, respectively. Then, evaluation tests of the prototype catalysts of Examples 22 to 26 were performed in the same manner as in Example 21, and the results are shown in Table 6 as in Example 21.

Examples 27 and 28 In Examples 27 and 28, the mixing amount of silica was the same as that in Example 2.
Different from 1, as shown in Table 5, each 10% by mass
And 40% by mass, respectively, to prepare catalysts in the same manner as in Example 21 to obtain trial catalysts of Examples 27 and 28, respectively. Then, evaluation tests of the prototype catalysts of Examples 27 and 28 were performed in the same manner as in Example 21, and the results are shown in Table 6 as in Example 21.

Comparative Examples 5-10 Using the same carrier as in Comparative Example 1, as shown in Table 5, the loading amounts of platinum were 0.1% by mass, 0.5% by mass, and 0.5% by mass, respectively.
1.0 wt%, 2.1 wt%, 5.6 wt% and 7.1
A catalyst was prepared in the same manner as in Example 21 except that the content was% by mass, and each was used as a catalyst of Comparative Examples 5 to 10.
Then, evaluation tests of the catalysts of Comparative Examples 5 to 10 were performed in the same manner as in Example 21, and the results are shown in Table 6 as in Example 21.

The relationship between the dearomatization rate shown in Table 6 obtained in Examples 21 to 26 and Comparative Examples 5 to 10 and the amount of platinum carried in each example was arranged as shown in FIG. In FIG. 2, the amount of platinum supported (mass%) is plotted on the horizontal axis, and the dearomatization ratio (%) is plotted on the vertical axis, with white squares representing Examples 21 to 26 and black squares representing Comparative Examples 5-1.
The data of 0 is shown. As a result, as can be seen from FIG. 2, the catalyst according to the present invention in which platinum is supported on a carrier containing γ-alumina as a main component and 20% by mass of silica as a carrier subcomponent on a carrier basis, has a platinum content of about 8%. The dearomatization rate is higher than that of the catalyst of Comparative Example in which the same amount or almost the same amount of platinum is supported on the carrier made of γ-alumina in the entire region up to mass%. That is, when the catalyst according to the present invention is used, it is possible to obtain a product oil having a lower content of aromatic compounds and a higher content of saturated hydrocarbon components as compared with the catalyst of the comparative example having the same platinum loading amount. You can This means that the catalyst according to the present invention is effective for the hydrogenation reaction of aromatic compounds in desulfurization-treated LCO under substantially the same hydrogen partial pressure and reaction temperature as in the conventional hydrotreatment. Shows. FIG.
Shows that the dearomatization rate increases as the platinum loading increases, that is, the aromatic compound content in the produced oil decreases. However, when the amount of platinum supported exceeds 8% by mass, the increase in the amount of dearomatization becomes apparently small with respect to the increase in the amount of platinum supported, and the hydrogenation performance of the aromatic compound of the catalyst approaches the saturated state. It is shown that. This is because the dispersibility of the active ingredient is extremely deteriorated due to aggregation of platinum metal which is the active ingredient. Therefore, in order to efficiently disperse the platinum metal and reduce the catalyst cost while maintaining the high hydrogenation performance of the aromatic compound, the amount of platinum supported should be limited to 8% by mass or less.

The amount of platinum carried in the trial catalyst was 0.5 each.
The relationship between the dearomatization rate shown in Table 6 obtained in Examples 22, 27, 28 and Comparative Example 6 which is% by mass, and the amount of silica mixed in the prototype catalyst of each example was arranged as shown in FIG. . In FIG. 3, the horizontal axis represents the silica mixture amount (mass%), and the vertical axis represents the dearomatization rate (%). As a result, as can be seen from FIG.
The catalyst according to the present invention in which 0.5% by mass of platinum is supported on a carrier in which γ-alumina is a main component and silica is mixed as a carrier subcomponent, the total amount of silica is 5 to 50% by mass based on the carrier. In the region, the rate of dearomatization is higher than that of the catalyst of the comparative example in which the same amount of platinum is supported on the carrier made of γ-alumina. That is, when the catalyst according to the present invention is used, it is possible to obtain a product oil having a lower content of aromatic compounds and a higher content of saturated hydrocarbon components as compared with the catalyst of the comparative example having the same platinum loading amount. You can This shows that the catalyst according to the present invention is effective for the hydrogenation reaction of aromatic compounds in desulfurized LCO under almost the same hydrogen partial pressure and reaction temperature as in the conventional hydrotreatment. There is.

Further, FIG. 3 shows that the amount of silica mixed in the carrier is 5
When it is less than 50% by mass or more than 50% by mass, the dearomatization rate is higher than that in the case of using the catalyst of Comparative Example, that is, the aromatic compound content in the produced oil is small, but the degree thereof is small. ing. This is because the silica content in the carrier is 5
If the amount is less than 50% by mass or more than 50% by mass, the amount of silica in the carrier is too small, or the amount of silica is too large, resulting in a hydrogenation reaction formed by mixing silica and alumina. The number of acid points that effectively act on the
It is thought that it will decrease. Therefore, as compared with the catalyst of the comparative example, the amount of silica mixture that clearly increases the dearomatization rate is in the range of 5 to 50% by mass, preferably in the range of 10 to 40% by mass. However, the effect of mixing silica, that is, mixing non-alumina-based inorganic substances is maximized.

[0057]

As described above in detail, according to the present invention, a carrier composed of an inorganic oxide containing alumina as a main component and a non-alumina system is used in an amount of 0.1 to 8% by mass based on the catalyst.
In addition to (metal conversion) platinum or 0.1 to 8 mass% (metal conversion) platinum, 0.1 to 2 mass% (oxide conversion) either alkali metal or alkaline earth metal is supported. By carrying out a catalytic hydrogenation reaction on a hydrocarbon oil using such a catalyst, the content of aromatic compounds in the hydrocarbon oil, for example, light oil, can be reduced. Using the catalyst according to the present invention, under the same conditions as conventional hydrotreating conditions, even in a feedstock containing a considerable amount of sulfur, by carrying out a catalytic hydrogenation reaction, aromatic compounds, particularly conventional It is possible to efficiently perform the hydrogenation treatment of the 1-ring aromatic compound and the sulfur compound, which is difficult with the above technique.

If the hydrocarbon oil hydrotreating catalyst according to the present invention is used, even if the feedstock oil is a hydrocarbon oil such as LCO containing a large amount of aromatic compounds, the aromatic compounds can be treated by the hydrotreatment. By efficiently reducing the amount of sulfur compounds and sulfur compounds, it is possible to suppress the generation of particulates in the exhaust gas and supply a gas oil base material having a low sulfur content at low cost. Further, since the reaction conditions of the catalyst are almost the same as the reaction conditions in the conventional hydrotreatment, there is an advantage that the conventional device can be diverted without major modification.

[Brief description of drawings]

FIG. 1 is a flow chart of an apparatus used in a performance test of a catalyst of Example 1.

FIG. 2 is a graph showing the relationship between the amount of platinum supported and the rate of dearomatization.

FIG. 3 is a graph showing the relationship between the amount of silica mixed and the rate of dearomatization.

[Explanation of symbols]

 10 Fixed Bed Type High Pressure Flow Reactor 12 Reactor 14 Catalyst Layer 16 Gas-Liquid Separator

Claims (3)

[Claims] 1. A carrier composed of an inorganic oxide containing alumina as a main component and containing a non-alumina-based material, on a catalyst basis, from 0.1 to 0.1.
8% by mass (metal equivalent) of platinum, or 0.1 to 8% by mass
A catalyst for hydrotreating a hydrocarbon oil, which carries 0.1 to 2% by mass (oxide conversion) of an alkali metal or an alkaline earth metal in addition to (metal conversion) platinum. 2. The hydrocarbon oil according to claim 1, wherein the content of the non-alumina-based inorganic oxide (oxide basis) is in the range of 5 to 50 mass% (carrier basis). Hydrotreating catalyst. 3. A carrier composed of an inorganic oxide containing alumina as a main component and containing a non-alumina-based material is used in an amount of 0.1 to 0.1 on a catalyst basis.
8% by mass (metal equivalent) of platinum, or 0.1 to 8% by mass
Hydrogen content in the range of 3 to 10 MPa in the presence of a catalyst supporting 0.1 to 2% by mass (oxide conversion) of an alkali metal or an alkaline earth metal in addition to (metal conversion) platinum. 2000 masses containing an aromatic compound under the conditions of pressure, temperature in the range of 200 to 400 ° C. and liquid hourly space velocity in the range of 0.1 to 5.0 hr ^−1.
A method for hydrotreating gas oil, which comprises carrying out a catalytic reaction of a gas oil fraction containing sulfur at a content rate of ppm or less.