JP2005270937A - Hydrogenation treatment catalyst for hydrocarbon oil and production method therefor, and hydrogenation treatment method for hydrocarbon oil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To produce a hydrogenation treatment catalyst, which shows little decrease in a catalyst activity by a coke degradation, and which enables the highly efficient removal of sulfur compounds in a hydrocarbon oil, particularly, a diesel oil fraction such as a low-pressure gas oil in a long period of time. <P>SOLUTION: The hydrogenation treatment of the hydrocarbon oil is characterized in that, in a catalyst standard, when considered in terms of oxides, 10-30mass % of at least one kind selected from the group VI metals, 1-1mass % at least one kind selected from the group VIII metals, 0.8-8mass % P, 2-14mass % C, and 0.1-0.8mass % Li are carried on an inorganic oxide carrier, its specific surface area is 110-300 m<SP>2</SP>/g, the pore volume is 0.35-0.6 ml/g, and the average pore diameter is about 65-180 Å. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a hydrotreating catalyst for hydrocarbon oil, a method for producing the same, and a hydrotreating method for hydrocarbon oil using the catalyst, and more particularly to a hydrocarbon oil, particularly a light oil fraction such as vacuum gas oil. A catalyst having excellent activity and a method for producing the same, in which the sulfur content and nitrogen content in the hydrocarbon oil can be reduced as compared with the conventional use of this type of catalyst. The present invention relates to a hydroprocessing method using this catalyst.

  There is a large amount of heavy oil such as atmospheric residue obtained by treating crude oil with an atmospheric distillation device, heavy oil such as vacuum gas oil and vacuum residue obtained by further treating atmospheric residue with a vacuum distillation device. Contains sulfur compounds. When these heavy oils are used as fuel without being desulfurized, sulfur oxides (SOx) are discharged into the atmosphere.

Therefore, conventionally, hydrodesulfurization treatment of heavy oil fractions by indirect desulfurization equipment and direct desulfurization equipment has been incorporated as one of the processes for producing various petroleum products from crude oil, and sulfur compounds can be removed. The hydrodesulfurization catalyst for the purpose of removing sulfur compounds in heavy oils is composed of molybdenum, tungsten, tungsten of group VIII, cobalt and nickel of the periodic table as active active ingredients, which are alumina, magnesia. Those supported on an inorganic oxide carrier such as silica and titania have been developed.
In recent years, awareness of global environmental issues has increased and regulations on the quality of various fuel oils have become stricter. The development of desulfurization technology that further reduces the sulfur content of vacuum gas oil, which is a major gasoline base stock, is awaited. As a technique for reducing the sulfur content in vacuum gas oil, it is usually considered that the operating conditions of the hydrodesulfurization apparatus, for example, the reaction temperature, the liquid space velocity, etc., are severe.
However, when the reaction temperature is increased, carbonaceous matter is deposited on the catalyst and the activity of the catalyst is rapidly reduced (hereinafter referred to as coke deterioration). Since the processing capacity decreases, it is necessary to expand the scale of the facility.
Therefore, the best way to achieve ultra-deep desulfurization of vacuum gas oil without harsh operating conditions is to develop a catalyst that has excellent desulfurization activity and can suppress carbonaceous deposition.

  In recent years, many studies have been conducted on the types of active metals, impregnation methods of active metals, improvement of catalyst support, control of pore structure of catalysts, activation methods, etc. Is reported and known.

  For example, a method is known in which an alumina or silica carrier is impregnated with a solution comprising an organic compound having a nitrogen-containing ligand as a complexing agent and an active metal and dried at 200 ° C. or lower (see Patent Document 1). ).

  Further, on the γ-alumina support, a Group 8 metal (hereinafter simply referred to as “Group 8 metal”) compound and a Group 6 metal (hereinafter simply referred to as “Group 6 metal”) compound of the Periodic Table; Further, there is known a method characterized by impregnating an impregnating solution containing phosphoric acid with an impregnating solution obtained by further adding a diol or ether and drying the impregnating solution at 200 ° C. or lower (see Patent Document 2). ).

  Further, an invention is known in which a carrier is impregnated with a solution composed of a Group 6 metal compound, a phosphorus component, a Group 8 metal compound, and citric acid, and then fired (see Patent Document 3).

  Furthermore, a catalyst comprising a group 6 metal compound, a group 8 metal compound, and phosphoric acid is supported on an oxide carrier to obtain a catalyst dried at 200 ° C. or lower, and a solution of an organic acid represented by a specific chemical formula is supported on the catalyst. And the method of drying at 200 degrees C or less is known (refer patent document 4).

On the other hand, a method for producing a catalyst in which an organic acid is impregnated twice is also known.
For example, an oxide carrier is impregnated with a solution consisting of a Group 6 metal compound, a Group 8 metal compound, an organic acid, and phosphoric acid to obtain a catalyst dried at 200 ° C. or lower, and further impregnated with an organic acid solution. A method of drying at a temperature of 0 ° C. or lower is known (see Patent Document 5).

  In addition, a technique for manufacturing a catalyst by impregnating an inorganic oxide support with a Group 8 metal compound and a heteropolyacid of a Group 6 metal and drying it is also known (see Patent Document 6).

Further, a method for producing a catalyst is known in which an oxide carrier is impregnated with a solution comprising molybdenum, tungsten, a group 8 metal compound, mercaptocarboxylic acid, and phosphoric acid (see Patent Document 7).
The main purpose of this method is to form a coordination compound of mercaptocarboxylic acid and molybdenum, tungsten, or a group 8 metal compound and highly disperse it on the catalyst support.
However, in this method, molybdenum and tungsten are highly dispersed on the support, making it difficult to laminate molybdenum disulfide as in the present invention described later, and a CoMoS phase or NiMoS phase that is particularly effective as a desulfurization active site. Type II (refers to Co and Ni active points existing in the edge portion of the second layer or more of molybdenum disulfide, Type I refers to Co and Ni active points present in the edge portion of the first layer of molybdenum disulfide, than Type II It is assumed that there is no formation of (low activity).
Moreover, the mercaptocarboxylic acid contains sulfur, and if it exists in the vicinity of the group 8 metal (Co, Ni) or forms a coordination, it does not become a desulfurization active site (CoMoS phase, NiMoS phase). In addition, there is a possibility of becoming an inactive Co9S8 species or Ni3S2 species.

  Further, it is known that organic acid is added and molybdenum disulfide is laminated to improve desulfurization performance (see Patent Document 8). However, this catalyst is required to further improve the coke deterioration.

  Regarding lithium, it is known that when a hydrogenolysis is carried out using a catalyst in which a hydrogenation active metal is supported on a carrier containing lithium oxide, an excellent conversion rate can be obtained without increasing precipitates. (See Patent Document 9) However, this catalyst requires further improvement in desulfurization activity.

  Further, a catalyst is known in which an alkali metal or an alkaline earth metal is added to a catalyst carrier having a total Brnsted acid amount of 50 μmol / g or more by TPD measurement to carry a hydrogenation active metal (see Patent Document 10). This catalyst is also required to be further improved to suppress coke deterioration.

  Further, a catalyst in which the amount of acid is controlled by adding lithium is also known (see Patent Document 11), but this catalyst is also required to be further improved to improve the desulfurization activity.

  The above catalysts have problems such as insufficient desulfurization performance with respect to vacuum gas oil and short catalyst life. For this reason, it is currently required to develop a catalyst having higher desulfurization activity and longer catalyst life than the conventional one that can realize advanced desulfurization of vacuum gas oil without harsh operating conditions. .

JP 61-114737 A Japanese Patent No. 2900771 Japanese Patent No. 2832033 JP-A-4-244238 JP-A-6-339635 JP-A-6-31176 JP-A-1-228552 JP 2003-299960 A JP-A-7-256106 JP 2000-8050 A JP 2003-103175 A

  An object of the present invention is to provide a hydrodesulfurization catalyst that is less likely to reduce catalyst activity due to coke degradation and can remove sulfur compounds in hydrocarbon oils, particularly gas oil fractions such as vacuum gas oil, over a long period of time and with high efficiency. It is another object of the present invention to provide a method for producing the hydrodesulfurization catalyst and a hydrodesulfurization method for vacuum gas oil using the hydrodesulfurization catalyst.

  The present inventors have studied to achieve the above object, and impregnated an inorganic oxide carrier with a solution containing a Group 6 metal compound, a Group 8 metal compound, an organic acid, phosphoric acid and lithium, Precise control of highly active desulfurization active sites (CoMoS phase, NiMoS phase, etc.) without forming inactive cobalt and nickel species by supporting predetermined amounts of these components and drying at temperatures below 200 ° C. Furthermore, since the acid property of the catalyst could be controlled to a suitable value, coke deposition could be suppressed. As a result, since the desulfurization reaction proceeds efficiently, it is possible to obtain a high-performance desulfurization catalyst that can easily achieve advanced desulfurization of hydrocarbon oil such as vacuum gas oil without making the reaction conditions severe. And gained knowledge.

That is, the hydrocarbon oil hydrotreating catalyst according to the present invention is selected from 10 to 30% by mass of Group 8 metal and at least one selected from Group 6 metal in terms of oxide on the basis of catalyst on the inorganic oxide carrier. 1 to 15% by mass, 0.8 to 8% by mass of phosphorus, 0.1 to 0.8% by mass of lithium, 2 to 14% by mass of carbon, and a specific surface area of 110 to 300 m ^2. / G, a pore volume of 0.35 to 0.6 m1 / g, and an average pore diameter of about 65 to 180 mm. This catalyst preferably has an acid point that generates an ammonia adsorption heat of 100 to 200 KJ / mol measured by a microcalorimetry method in a range of 270 to 380 μmol per 1 g of the catalyst. It is preferable that the average value of the number of laminated molybdenum disulfide layers observed with a transmission electron microscope is 2.5 to 5.
Moreover, the method for producing the catalyst according to the present invention is based on an inorganic oxide carrier having physical properties of a specific surface area of 160 to 500 m ² / g, a pore volume of 0.55 to 0.9 m1 / g, and an average pore diameter of 60 to 150 mm. And a compound containing at least one selected from Group 8 metals, a compound containing at least one selected from Group 6 metals, a solution containing an organic acid, lithium and phosphoric acid, a catalyst standard, an oxide In terms of conversion, the group 6 metal is 10 to 30% by mass, the group 8 metal is 1 to 15% by mass, the phosphorus is 0.8 to 8% by mass, the lithium is 0.1 to 0.8% by mass, and the carbon is 2 to 14% by mass. It is made to carry | support so that it may become, and it is made to dry at 200 degrees C or less.
Furthermore, the hydrodesulfurization method using the catalyst according to the present invention is performed under the conditions of a hydrogen partial pressure of 3 to 8 MPa, a treatment temperature of 300 to 420 ° C., and a liquid space velocity of 0.3 to 5 hr ⁻¹ in the presence of the catalyst. It is characterized by conducting a catalytic reaction of a hydrocarbon fraction.

  According to the present invention, a catalyst having a specific composition and a specific physical property using the group 6 metal and the group 8 metal as an active metal is used, and a decrease in catalytic activity due to coke deterioration is small. The sulfur compound in the gas oil fraction such as can be removed with high efficiency over a long period of time.

The present invention can widely use hydrocarbon oils as processing target oils, but can be suitably applied to the processing of light oil fractions such as vacuum gas oils.
Typical examples of the properties of the feedstock to which the present invention can be suitably applied include those having a boiling range of 150 to 550 ° C. and a sulfur content of 5% by mass or less.

  In the catalyst of the present invention, various inorganic oxide carriers can be used, and among these, an alumina carrier is preferably used. The production method of the alumina carrier preferably used for the catalyst of the present invention is not particularly limited, and a usual method can be adopted. That is, by neutralizing a water-soluble aluminum compound such as aluminum sulfate, nitrate or chloride with a base such as ammonia, or neutralizing an alkali metal aluminate with an acidic aluminum salt or acid, etc. The produced aluminum hydrogel or hydrosol can be produced by applying a general formulation such as washing, aging, molding, drying, and baking.

  In order to obtain an alumina carrier having structural properties suitable as a catalyst carrier, it is only necessary to appropriately adjust the pH, concentration, time, temperature, etc. of these chemicals by adding a precipitating agent or a neutralizing agent. For example, if the pH at the time of gel formation is performed on the acidic side, the specific surface area increases. In the present invention, it is preferable that the pH is about 4 to 8 and the temperature is about 15 to 90 ° C.

After the gel is formed, aging, cleaning and removing impurities, and dehydration drying are performed. The aging is preferably performed at a pH of 4 to 9 and a temperature of about 15 to 90 ° C. for about 1 to 25 hours. Outside these ranges, not only is it difficult to remove impurities in the alumina gel after aging, but the surface area of the alumina gel is reduced.
The dehydration drying is performed by adjusting the water content without applying heat to the alumina gel. For example, it is dehydrated and dried by a method such as natural filtration at about 15 to 90 ° C. and about 0.01 to 2 MPa, suction filtration, pressure filtration, etc., so that the water content after dehydration drying is about 60 to 90% by mass. It is preferable to make it. By adjusting the water content without applying extra heat to the alumina gel, the surface structure of the alumina can be controlled, and the hydrodesulfurization activity of the catalyst can be improved.

  The carrier is formed after dehydration and drying. The molding method is not particularly limited, and a general method such as extrusion molding, tableting molding, or granulation in oil can be used. The pore volume and pore distribution, which are structural properties of alumina, can also be controlled by adjusting the pressure and speed during molding.

  The shape of the alumina support is preferably a cylindrical, trilobal, quadrilobal, dumbbell, or ring pellet in consideration of the distribution of the heavy oil fraction catalyst layer. A shape with a small pressure loss (pressure difference) is selected. Similarly, the pellet diameter is preferably in the range of 1 to 2 mm so that pressure loss does not increase before and after the catalyst layer under the reaction conditions. In addition, a pellet diameter is represented by the long diameter of the cross section of the thickest part except what the shape of a pellet is a cylinder.

  After molding, the alumina support can be obtained by drying at room temperature to about 150 ° C. for about 3 to 24 hours, followed by firing at about 200 to 600 ° C. for about 3 to 24 hours.

  As will be described later, the catalyst of the present invention is prepared by simply drying at 200 ° C. or lower after the active component is supported on an inorganic oxide carrier, especially an alumina carrier. Side fracture strength, close-packed bulk density, etc.) are obtained by firing an inorganic oxide carrier such as an alumina carrier. The firing of an alumina carrier involves mechanical strength, specific surface area, pore volume, and average pore diameter. In view of the above characteristics, it is preferable to carry out the reaction at about 580 ° C. for about 1.5 hours to about 700 ° C. for about 3 hours.

The specific surface area, pore volume, and average pore diameter of an inorganic oxide carrier such as an alumina carrier are such that the specific surface area is 160 to 500 m ² / g, preferably a catalyst having high hydrodesulfurization activity for hydrocarbon oils. 175 to 450 m ² / g, pore volume of 0.55 to 0.9 ml / g, preferably 0.65 to 0.8 ml / g, average pore diameter of 60 to 150 mm, preferably 65 to 110 mm There is.

The reason is as follows.
In the impregnating solution, the group 6 metal and the group 8 metal are considered to form a complex (the group 6 metal is coordinated with phosphoric acid to form a heteropolyacid, and the group 8 metal is coordinated to an organic acid to form an organometallic complex). Therefore, when the specific surface area of the support is less than 160 m ² / g, it is difficult to highly disperse the metal due to the bulk of the complex during impregnation. Presumably, precise control of the formation of active sites (CoMoS phase, NiMoS phase, etc.) becomes difficult.
When the specific surface area is larger than 500 m ² / g, the pore diameter becomes extremely small, so that the pore diameter of the catalyst also becomes small. When the pore diameter of the catalyst is small, the diffusion of sulfur compounds into the catalyst pores becomes insufficient, and the desulfurization activity is lowered.

When the pore volume is less than 0.55 ml / g, a small amount of solvent enters the pore volume when the catalyst is prepared by the usual impregnation method. When the amount of the solvent is small, the solubility of the active metal compound is deteriorated, the dispersibility of the metal is lowered, and a low activity catalyst is obtained. In order to increase the solubility of the active metal compound, there is a method in which a large amount of acid such as nitric acid is added. However, if too much is added, the support has a low surface area, which is a major cause of desulfurization performance degradation.
When the pore volume is larger than 0.9 ml / g, the specific surface area becomes extremely small, the dispersibility of the active metal is deteriorated, and the catalyst has a low desulfurization activity.

When the average pore diameter is less than 60 mm, the pore diameter of the catalyst supporting the active metal is also small. When the pore diameter of the catalyst is small, the diffusion of sulfur compounds into the catalyst pores becomes insufficient, and the desulfurization activity is lowered.
When the average pore diameter is larger than 150 mm, the specific surface area of the catalyst becomes small. When the specific surface area of the catalyst is small, the dispersibility of the active metal is deteriorated and the catalyst has a low desulfurization activity.

The Group 6 metal contained in the catalyst of the present invention is preferably molybdenum or tungsten, and particularly preferably molybdenum.
The content of the Group 6 metal is 10 to 30% by mass, preferably 16 to 28% by mass in terms of catalyst and oxide.
If it is less than 10% by mass, it is not sufficient for exhibiting the effect due to the Group 6 metal. If it exceeds 30% by mass, the Group 6 metal is agglomerated in the impregnation (supporting) process of the Group 6 metal, and 6 Not only the dispersibility of the group metal is deteriorated, but the catalytic activity is not improved due to exceeding the limit of the content of the group 6 metal to be efficiently dispersed or the surface area of the catalyst being greatly reduced.

The group 8 metal is preferably cobalt or nickel.
The content of the group 8 metal is 1 to 15% by mass, preferably 3 to 8% by mass in terms of catalyst and oxide.
If the amount is less than 1% by mass, the active sites attributed to the group 8 metal cannot be obtained sufficiently. If the amount exceeds 15% by mass, the group 8 metal compound is aggregated in the step of containing (supporting) the group 8 metal. In addition to inactive cobalt, nickel species, Co9S8 species, Ni3S2 species, CoO species, NiO species, etc., Co spinel species incorporated into the support lattice, Ni It is considered that spinel species and the like are generated, and not only the catalytic performance is not improved, but also the catalytic performance is lowered.

In the above-described contents of the Group 8 metal and the Group 6 metal, the optimum mass ratio of the Group 8 metal to the Group 6 metal is preferably [group 8 metal] / [group 8 metal + group 6 metal] in terms of oxide. The value is about 0.1 to 0.25.
If this value is less than about 0.1, the formation of CoMoS phase, NiMoS phase, etc., which are considered as active sites for desulfurization, is suppressed, and the degree of desulfurization activity improvement is not so high. Generation of active cobalt and nickel species (Co9S8 species, Ni3S2 species) is promoted, and there is a tendency to suppress improvement in catalyst activity.

The phosphorus content is 0.8 to 8% by mass, preferably 1.5 to 6% by mass, more preferably 2 to 5% by mass in terms of catalyst and oxide. Phosphorus may be contained at the time of preparing an oxide carrier such as alumina by a kneading method, or may be supported by an impregnation method after preparing the carrier.
If it is less than 0.8% by mass, the group 6 metal cannot form a heteropolyacid on the catalyst surface, so it is estimated that the highly dispersed MoS2 phase cannot be formed in the preliminary sulfidation step, and the above desulfurization active sites cannot be sufficiently arranged. The In particular, in order to form the molybdenum disulfide layer on the catalyst after the preliminary sulfidation so that the average number of layers is 2.5 to 5, it is preferably 1.5% by mass or more.
On the other hand, if the amount is more than 8% by mass, the group 6 metal sufficiently forms a heteropolyacid on the catalyst surface, so that the high-quality desulfurization active sites are formed in the preliminary sulfidation step, but excess phosphorus is poisoned. Since desulfurization active sites are coated as a substance, it is presumed to be the main cause of the decrease in activity.

  In the present invention, a basic element is used to control the acid properties of the catalyst. Alkali metals and alkaline earth metals are preferred, more preferably alkali metals, particularly lithium. In the present invention, lithium is used, and the supported amount is 0.1 to 0.8% by mass in terms of oxide based on the catalyst. By setting the loading in the above range, it is possible to control to a desired acid property and acid amount and to obtain a catalyst in which coke deterioration hardly occurs while maintaining high activity. If the amount of lithium supported is less than 0.1% by mass, the desired acid properties and acid amount cannot be controlled, causing coke deterioration. On the other hand, when the amount of lithium supported exceeds 0.8% by mass, the acid sites necessary for the catalytic activity are reduced, and the catalytic activity is lowered.

The carbon content is 2 to 14% by mass, preferably 3 to 10% by mass in terms of catalyst and element.
This carbon is derived from an organic acid, preferably citric acid, and if it is less than 2% by mass, the group 8 metal does not sufficiently form a complex compound with the organic acid on the catalyst surface. Since the uncomplexed group 8 metal is sulfided prior to the sulfurization of the group 6 metal, desulfurization active sites (CoMoS phase, NiMoS phase, etc.) are not sufficiently formed, and are inactive cobalt and nickel species. It is estimated that Co ₉ S ₈ species, Ni ₃ S ₂ species and the like are formed.
If it exceeds 14% by mass, the group 8 metal sufficiently forms a complex compound with the organic acid on the surface of the catalyst, so that many desulfurization active sites can be obtained in the preliminary sulfidation step, but excess carbon is poisoned. Since the desulfurization active site is coated as a substance, it is estimated that it causes a decrease in activity.

  Regarding the amount of metal supported, “display in terms of oxide based on the catalyst” means that the mass of all metal species contained in the catalyst is calculated as the oxide of each metal, and the total mass is calculated for each metal. It means to display by the value divided by the oxide mass. Aluminum was trivalent, molybdenum was hexavalent, nickel and cobalt were bivalent, and lithium was monovalent metal. The amount of metal supported was measured by ICP spectroscopy (inductively coupled high-frequency plasma spectroscopy) after dissolving the catalyst in a mixed acid and displayed in terms of catalyst-based metal oxide.

The catalyst of the present invention has the above composition in order to increase the hydrodesulfurization activity for hydrocarbon oils, particularly gas oil fractions such as vacuum gas oil, and the specific surface area, pore volume and average pore diameter are as follows: Must be the value of.
The specific surface area (specific surface area measured by the nitrogen adsorption method (BET method)) is about 110 to 300 m ² / g.
Below about 110 m ² / g, a Group 6 metal (coordinating with phosphoric acid to form a heteropolyacid) and a Group 8 metal (coordinating with an organic acid to form an organic metal are considered to form a complex on the catalyst surface. Complex) is not sufficiently highly dispersed due to the bulk of the complex, and as a result, even if it is subjected to sulfidation treatment, it becomes difficult to precisely control the above-mentioned active site formation, resulting in a catalyst with low desulfurization activity. If it is larger than about 300 m ² / g, the pore diameter becomes extremely small, so the pore diameter of the catalyst also becomes small, and during the hydrotreatment, the diffusion of sulfur compounds into the catalyst pores becomes insufficient, Desulfurization activity decreases.

  The pore volume measured by the mercury intrusion method is about 0.35 to 0.6 m1 / g, preferably about 0.38 to 0.55 m1 / g. If it is less than about 0.35 m1 / g, the diffusion of sulfur compounds in the catalyst pores becomes insufficient during the hydrotreatment, resulting in insufficient desulfurization activity. The specific surface area becomes extremely small, the dispersibility of the active metal is lowered, and the catalyst has a low desulfurization activity.

The average pore diameter in the pore distribution measured by mercury porosimetry is about 65 to 180 mm, preferably about 70 to 145 mm. If it is less than about 65 mm, the reactant does not easily diffuse into the pores, so the desulfurization reaction does not proceed efficiently. If it is larger than about 180 mm, the diffusibility in the pores is good, but the surface area in the pores decreases. Therefore, the effective specific surface area of the catalyst is reduced and the activity is lowered.
In order to increase the effective number of pores satisfying the above-mentioned pore conditions, the pore size distribution of the catalyst, that is, the proportion of pores having an average pore size of about ± 15 mm is preferably about 75% or more, preferably Is about 80% or more.
Moreover, the pore distribution is preferably monomodal. If the pore size distribution of the catalyst is not steep, the pores not involved in the activity increase and the desulfurization activity decreases.

  It is preferable that the catalyst of the present invention has an acid point that generates an ammonia adsorption heat of 100 to 200 KJ / mol by a microcalorimetry method in a range of 270 to 380 μmol, preferably 290 to 380 μmol, per 1 g of the catalyst. The heat of adsorption generated when ammonia is adsorbed on the acid sites on the catalyst surface varies depending on the acid properties of the acid sites. A catalyst having an acid point with an adsorption heat of 100 to 200 KJ / mol within the above range has a sufficient active site in hydrodesulfurization reaction of vacuum gas oil and has very little deterioration over time. If the acid point is less than 270 μmol / g, the catalytic activity is not sufficient, and if it exceeds 380 μmol / g, desired coke formation cannot be suppressed, such being undesirable.

The catalyst of the present invention preferably has an average value of the number of laminated molybdenum disulfide layers of 2.5 to 5 when observed with a transmission electron microscope after sulfiding.
That is, this molybdenum disulfide layer is formed on the inorganic oxide support and serves to increase the contact area of the catalyst, and active points such as a CoMoS phase and a NiMoS phase are formed in the layer. In the case of a catalyst having an average number of layers of less than 2.5, the ratio of type I of the low activity CoMoS phase or NiMoS phase is increased, and high activity is not exhibited. Although NiMoS phase type II is formed, the absolute number of active sites is reduced, so that high activity is not exhibited.

In order to obtain the catalyst of the present invention having the above characteristics, it is preferable to use the method of the present invention described below.
That is, a compound comprising at least one of the above Group 6 metals, a compound containing at least one of the above Group 8 metals in an inorganic oxide carrier such as an alumina carrier having the above-described properties, and an organic material comprising the above components, organic Depending on the method in which a solution containing acid, lithium, and phosphoric acid is used, the group 6 metal, the group 8 metal, phosphorus, lithium, and carbon are supported so as to have the above-described contents and dried. Specifically, for example, The inorganic oxide carrier is impregnated with a solution containing these compounds and dried.

Examples of the compound containing a Group 6 metal used in the impregnation solution include molybdenum trioxide, molybdophosphoric acid, ammonium molybdate, molybdic acid, and the like, and preferably molybdenum trioxide and molybdophosphoric acid.
The amount of these compounds added to the impregnation solution is such that the Group 6 metal is contained in the resulting catalyst within the above-described range.

Examples of the compound containing a group 8 metal include cobalt carbonate, nickel carbonate, cobalt citrate compound, nickel citrate compound, cobalt nitrate hexahydrate, nickel nitrate hexahydrate, and preferably cobalt carbonate and nickel carbonate. , Cobalt citrate compounds and nickel citrate compounds. Particularly preferred are cobalt citrate compounds and nickel citrate compounds, which have a lower decomposition rate than cobalt carbonate and nickel carbonate.
That is, when the decomposition rate is high, apart from the molybdenum disulfide layer, cobalt or nickel forms a unique layer, and the formation of a highly active CoMoS phase or NiMoS phase becomes insufficient. When the speed is low, these highly active phases can be sufficiently formed at the rim-edge portion of molybdenum disulfide.

Examples of cobalt citrate include cobalt citrate (Co ₃ (C ₆ H ₅ O ₇ ) ₂ ), cobalt hydrogen citrate (CoHC ₆ H ₅ O ₇ ), and cobalt citrate oxysalt (Co ₃ (C ₆ H ₅ O ₇ ) ₂ .CoO) and the like, and as nickel citrate, nickel citrate (Ni ₃ (C ₆ H ₅ O ₇ ) ₂ ), nickel hydrogen citrate (NiHC ₆ H ₅ O) ₇ ), nickel citrate oxysalt (Ni ₃ (C ₆ H ₅ O ₇ ) ₂ .NiO), and the like.
For example, in the case of cobalt, this method of producing a citric acid compound of cobalt and nickel can be obtained by dissolving cobalt carbonate in an aqueous solution of citric acid. You may use for the catalyst preparation as it is, without removing the water | moisture content of the citric acid compound obtained by such a manufacturing method.
The amount of these compounds added to the impregnation solution is such that the group 8 metal is contained within the above-described range in the resulting catalyst.

Organic acids include citric acid monohydrate, anhydrous citric acid, isocitric acid, malic acid, tartaric acid, oxalic acid, succinic acid, glutaric acid, adipic acid, benzoic acid, phthalic acid, isophthalic acid, salicylic acid, malonic acid, etc. And citric acid monohydrate is preferred. It is important that these organic acids use compounds that are substantially free of sulfur.
When citric acid is used as the organic acid, citric acid alone or a citric acid compound with cobalt or nickel (group 8 metal) described above may be used.
The amount of the organic acid added is not particularly limited, but it is important that the amount of carbon remaining in the obtained catalyst is such that the carbon content remains, and the organic acid / It is preferable to set it as group 8 metal = 0.2-1.2. If this molar ratio is less than 0.2, active sites attributed to Group 8 metals may not be sufficiently obtained, and if it exceeds 1.2, the impregnating solution becomes highly viscous, so that the supporting process takes time. It will be.
When a group 8 metal citrate compound is used, an organic acid is further added when the amount of the organic acid is insufficient.

Examples of phosphoric acid include various phosphoric acids, specifically orthophosphoric acid, metaphosphoric acid, pyrophosphoric acid, triphosphoric acid, tetraphosphoric acid, polyphosphoric acid and the like, and orthophosphoric acid is particularly preferable.
As the phosphoric acid, molybdophosphoric acid which is a compound with a Group 6 metal can also be used. In this case, phosphoric acid is further added when phosphorus is not contained in the obtained catalyst in the above content.

  Various types of lithium can be used. Specific examples include lithium hydroxide, lithium nitrate, lithium oxalate, lithium sulfate, lithium chloride, lithium carbonate, and lithium acetate, with lithium hydroxide, lithium nitrate, and lithium acetate being preferred.

On the other hand, the desulfurization activity and coke deterioration of the prepared catalyst are greatly affected by the lithium loading method. The impregnation method is preferable because the acid amount and acid properties on the catalyst surface can be efficiently controlled.
The active metal and lithium may be supported in any order. That is, the active metal and lithium may be supported simultaneously, or the active metal may be supported after the lithium is supported and then dried and fired to form a metal oxide.
Particularly preferred is a method in which both of the active metal and lithium are supported by the impregnation method. In this case, the active metal and lithium may be impregnated simultaneously or individually. Moreover, when impregnating individually, the impregnation order is impregnated with lithium first, dried and fired to obtain a metal oxide, and then impregnated with an active metal.

  If the above Group 6 metal compound or Group 8 metal compound is not sufficiently dissolved in the impregnation solution, an acid (nitric acid, organic acid << citric acid, malic acid, tartaric acid, etc. >>) together with these compounds May be used, preferably an organic acid is used. When an organic acid is used, carbon from the organic acid may remain in the resulting catalyst. It is important to be within range.

In the above impregnation solution, the solvent used for dissolving each of the above components is water.
If the amount of the solvent used is too small, the support cannot be sufficiently impregnated, and if it is too large, the dissolved active metal does not impregnate on the support and adheres to the edge of the impregnation solution container. Thus, the amount is 50 to 90 g, preferably 60 to 85 g based on 100 g of the carrier.

  The above components are dissolved in the solvent to prepare an impregnation solution. The temperature at this time may be over 0 ° C. and 100 ° C. or less, and if the temperature is within this range, the above components are good in the solvent. Can be dissolved.

  The pH of the impregnating solution is preferably less than 5. When it is 5 or more, hydroxide ions increase, the coordination ability between the organic acid and the group 8 metal is weakened, and complex formation of the group 8 metal is suppressed. As a result, the number of desulfurization active points (CoMoS phase, NiMoS phase) cannot be increased significantly.

The impregnating solution thus prepared is impregnated with the inorganic oxide carrier, and the components in the solution are supported on the inorganic oxide carrier.
Various conditions can be adopted as the impregnation conditions. Usually, the impregnation temperature is preferably more than 0 ° C. and less than 100 ° C., more preferably 10 to 50 ° C., further preferably 15 to 30 ° C., and the impregnation time. Is preferably 15 minutes to 3 hours, more preferably 20 minutes to 2 hours, and even more preferably 30 minutes to 1 hour.
If the temperature is too high, drying occurs during the impregnation and the degree of dispersion becomes uneven.
Moreover, it is preferable to stir during the impregnation.

After carrying the solution impregnation, water is removed to some extent (so that the LOI << Loss on ignition >> is about 50% or less) at room temperature to about 80 ° C. in a nitrogen stream, air stream, or vacuum, and then air Drying is performed at 200 ° C. or less, preferably at about 80 to 200 ° C. for about 10 minutes to 24 hours, more preferably at about 100 to 150 ° C. for about 5 to 20 hours in an air stream, a nitrogen stream or in a vacuum.
When drying is performed at a temperature higher than 200 ° C., the organic acid that appears to be complexed with the metal is released from the catalyst surface. As a result, even if the resulting catalyst is subjected to sulfidation treatment, the active sites (CoMoS phase, NiMoS phase, etc.) is difficult to precisely control, and inactive cobalt, nickel species of Co ₉ S ₈ species, Ni ₃ S ₂ species, etc. are formed, and the average number of layers of molybdenum disulfide is more than 2.5. It is considered that the amount of the catalyst decreases, and becomes a catalyst with low desulfurization activity.

In the present invention, the shape of the catalyst is not particularly limited, and various shapes usually used for this type of catalyst, for example, a cylindrical shape, a trilobal type, a four-leaf type, and the like can be adopted. The size of the catalyst is usually preferably about 1 to 2 mm in diameter and about 2 to 5 mm in length.
The mechanical strength of the catalyst is preferably about 2 lbs / mm or more in terms of side surface breaking strength (SCS << Side crash strength >>). By doing so, it is avoided that the catalyst charged in the reactor is destroyed, a differential pressure is generated in the reactor, and the hydration operation cannot be continued.
The close-packed bulk density (CBD) of the catalyst is preferably about 0.6 to 1.2 (g / ml).
The distribution state of the active metal in the catalyst is preferably a uniform type in which the active metal is uniformly distributed in the catalyst.

The hydrotreating method of the present invention includes a hydrocarbon oil containing the above catalyst and a sulfur compound under conditions of a hydrogen partial pressure of about 3 to 8 MPa, a temperature of about 300 to 420 ° C., and a liquid space velocity of about 0.3 to 5 hr ⁻¹ . In particular, the desulfurization is performed by contacting a light oil fraction such as vacuum gas oil to reduce sulfur compounds including hardly desulfurizable sulfur compounds in the hydrocarbon oil. The product oil obtained by the process of the present invention can be less sulfur and nitrogen than by the prior art.

In order to carry out the hydrotreating method of the present invention on a commercial scale, a fixed bed, moving bed or fluidized bed type catalyst layer of the catalyst of the present invention is formed in the reactor, and the feedstock is introduced into the reactor. The hydrogenation reaction may be performed under the above conditions.
Most commonly, a fixed bed catalyst layer is formed in the reactor, feedstock is introduced into the top of the reactor, the fixed bed is passed from bottom to top, and the product is drained from the top of the reactor. Is.
Further, it may be a one-stage hydrotreating method in which the catalyst of the present invention is filled in a single reactor, or a multi-stage continuous hydrotreating method in which several reactors are filled. Good.

Note that the catalyst of the present invention is activated by sulfiding in a reactor before use (that is, prior to performing the hydrotreatment method of the present invention). This sulfidation treatment is conducted at about 200 to 400 ° C., preferably about 250 to 350 ° C. under a hydrogen atmosphere at normal pressure or higher, and a petroleum distillate containing sulfur compounds, dimethyl disulfide or disulfide. It is performed using a material added with a sulfurizing agent such as carbon or hydrogen sulfide.
By this sulfidation treatment, the catalyst of the present invention forms a molybdenum disulfide layer having an average number of layers of 2.5 to 5 as described above, and a highly active CoMoS is formed on the rim-edge portion of the molybdenum disulfide. The active point of the phase or NiMoS phase is formed.

(Preparation of catalyst)
Example 1
0.37 g of lithium nitrate was dissolved in 41 g of ion-exchanged water, dropped in 50 g of alumina pellets having a specific surface area of 320 m ² / g in an eggplant type flask, and then immersed at room temperature for 3 hours. Then, it air-dried in nitrogen stream, and baked for about 4 hours at 500 degreeC in the muffle furnace, and obtained the lithium carrying | support alumina support | carrier. Furthermore, 29.81 g of molybdophosphoric acid, 7.68 g of cobalt carbonate, 3.8 g of orthophosphoric acid, and 8.40 g of citric acid monohydrate were dissolved in 33.0 g of ion-exchanged water. All of this aqueous solution was dropped into the lithium-supported alumina in the eggplant-shaped flask and then immersed for 3 hours at room temperature. Thereafter, it was air-dried in a nitrogen stream and dried in a muffle furnace at 120 ° C. for about 16 hours to obtain Catalyst A.

Example 2
Except that the amount of lithium nitrate was 2.30 g, everything was prepared in the same manner as in Example 1 to obtain Catalyst B.

Example 3
A catalyst C was obtained in the same manner as in Example 1 except that the amount of lithium nitrate was changed to 2.96 g.

Example 4
In 33.0 g of ion-exchanged water, 29.81 g of molybdophosphoric acid, 7.68 g of cobalt carbonate, 3.8 g of orthophosphoric acid, 2.30 g of lithium nitrate and 8.4 g of citric acid monohydrate were dissolved. All of this aqueous solution was dropped in 50 g of alumina pellets having a specific surface area of 320 m ² / g in an eggplant-shaped flask and then immersed for 3 hours at room temperature. Thereafter, it was air-dried in a nitrogen stream and dried in a muffle furnace at 120 ° C. for about 16 hours to obtain catalyst D.

Example 5
2.30 g of lithium nitrate was dissolved in 41 g of ion-exchanged water, dropped in 50 g of alumina pellets having a specific surface area of 190 m ² / g in an eggplant type flask, and then immersed at room temperature for 3 hours. Then, it air-dried in nitrogen stream, and baked for about 4 hours at 500 degreeC in the muffle furnace, and obtained the lithium carrying | support alumina support | carrier. Further, 29.81 g of molybdophosphoric acid, 7.68 g of cobalt carbonate, 3.80 g of orthophosphoric acid, and 8.40 g of citric acid monohydrate were dissolved in 33.0 g of ion-exchanged water. All of this aqueous solution was dropped into the lithium-supported alumina in the eggplant-shaped flask and then immersed for 3 hours at room temperature. Thereafter, it was air-dried in a nitrogen stream and dried in a muffle furnace at 120 ° C. for about 16 hours to obtain Catalyst E.

Example 6
Except that the specific surface area of the alumina pellet used was 165 m ² / g, everything was adjusted in the same manner as in Example 5 to obtain Catalyst F.

Comparative Example 1
In 33.0 g of ion-exchanged water, 29.81 g of molybdophosphoric acid, 7.68 g of cobalt carbonate, and 3.80 g of orthophosphoric acid were dissolved. All of this aqueous solution was dropped into 50 g of alumina pellets in an eggplant-shaped flask and then immersed for 3 hours at room temperature. Then, it air-dried in nitrogen stream, and baked at 500 degreeC in the muffle furnace for about 4 hours, and obtained the catalyst g.

Comparative Example 2
2.30 g of lithium nitrate was dissolved in 41 g of ion-exchanged water, dropped in 50 g of alumina pellets having a specific surface area of 320 m ² / g in an eggplant type flask, and then immersed at room temperature for 3 hours. Then, it air-dried in nitrogen stream, and baked for about 4 hours at 500 degreeC in the muffle furnace, and obtained the lithium carrying | support alumina support | carrier. Further, 29.81 g of molybdophosphoric acid, 7.68 g of cobalt carbonate, 3.80 g of orthophosphoric acid, and 8.40 g of citric acid monohydrate were dissolved in 33.0 g of ion-exchanged water. All of this aqueous solution was dropped into the lithium-supported alumina in the eggplant-shaped flask and then immersed for 3 hours at room temperature. Then, it air-dried in nitrogen stream, and baked at 500 degreeC in the muffle furnace for about 4 hours, and the catalyst h was obtained.

Comparative Example 3
29.81 g of molybdophosphoric acid, 7.68 g of cobalt carbonate, 3.80 g of orthophosphoric acid, and 8.40 g of citric acid monohydrate were dissolved in 33.0 g of ion-exchanged water. All of this aqueous solution was dropped in 50 g of alumina pellets having a specific surface area of 320 m ² / g in an eggplant-shaped flask and then immersed for 3 hours at room temperature. Thereafter, it was air-dried in a nitrogen stream and dried in a muffle furnace at 120 ° C. for about 16 hours to obtain catalyst i.

Comparative Example 4
2.30 g of lithium nitrate was dissolved in 41 g of ion-exchanged water, dropped in 50 g of alumina pellets having a specific surface area of 150 m ² / g in an eggplant type flask, and then immersed at room temperature for 3 hours. Then, it air-dried in nitrogen stream, and baked for about 4 hours at 500 degreeC in the muffle furnace, and obtained the lithium carrying | support alumina support | carrier. Further, 29.81 g of molybdophosphoric acid, 7.68 g of cobalt carbonate, 3.80 g of orthophosphoric acid, and 8.40 g of citric acid monohydrate were dissolved in 33.0 g of ion-exchanged water. All of this aqueous solution was dropped into the lithium-supported alumina in the eggplant-shaped flask and then immersed for 3 hours at room temperature. Thereafter, it was air-dried in a nitrogen stream and dried in a muffle furnace at 120 ° C. for about 16 hours to obtain catalyst j.

Comparative Example 5
7.56 g of lithium nitrate was dissolved in 41 g of ion-exchanged water, dropped in 50 g of alumina pellets having a specific surface area of 320 m ² / g in an eggplant type flask, and then immersed for 3 hours at room temperature. Then, it air-dried in nitrogen stream, and baked for about 4 hours at 500 degreeC in the muffle furnace, and obtained the lithium carrying | support alumina support | carrier. Further, 29.81 g of molybdophosphoric acid, 7.68 g of cobalt carbonate, 3.80 g of orthophosphoric acid, and 8.40 g of citric acid monohydrate were dissolved in 33.0 g of ion-exchanged water. All of this aqueous solution was dropped into the lithium-supported alumina in the eggplant-shaped flask and then immersed for 3 hours at room temperature. Thereafter, it was air-dried in a nitrogen stream and dried in a muffle furnace at 120 ° C. for about 16 hours to obtain catalyst k.

[Catalyst properties]
The chemical properties of the catalysts obtained in Examples 1 to 5 and Comparative Examples 1 to 5 are shown in Table 1, the physical properties after calcination at 500 ° C. for 4 hours, and the ammonia adsorption of 100 to 200 KJ / mol measured by the microcalorimetry method. Table 2 shows the amount of acid sites that generate heat (per gram of catalyst) and the structural properties of the catalyst.
A method for analyzing these properties is shown below.

[Analysis of chemical and physical properties]
-The carbon mass was combusted at 950 ° C using a CHN analyzer (MT-5) manufactured by Yanagimoto Co., Ltd. after grinding the catalyst in a mortar, and the combustion product gas was measured with a differential thermal conductivity meter. It was measured.
The specific surface area was measured by a nitrogen adsorption method (BET method) using a surface area measuring device (Bell Soap 28) manufactured by Nippon Bell Co., Ltd. after vacuum degassing of the catalyst at 400 ° C. for 1 hour. The pore diameter was measured by mercury porosimetry using the same treated catalyst (manufactured by Shimadzu Corp. (AUTOPORE-9520)).
-The lamination | stacking number of the molybdenum disulfide layer was measured in the following way using the transmission electron microscope (TEM) (JEOL company brand name "JEM-2010").
1. The catalyst is packed in a flow-type reaction tube, kept in a nitrogen stream at room temperature for 5 minutes, the atmospheric gas is switched to H ₂ S (5% by volume) / H ₂ , the temperature is increased at a rate of 5 ° C./min, and the temperature reaches 400 ° C. After reaching, it was held for 1 hour. Thereafter, the temperature was lowered to 200 ° C. under the same atmosphere, the atmosphere gas was switched to nitrogen, the temperature was lowered to room temperature, and the sulfiding treatment was completed.
2. The catalyst after the sulfurization treatment was pulverized in an agate mortar.
3. A small amount of the ground catalyst was dispersed in acetone.
4). The obtained suspension was dropped on a microgrid and dried at room temperature to prepare a sample.
5). The sample was set in the measurement part of TEM and measured at an acceleration voltage of 200 kV. The direct magnification was 200,000 times and 5 fields of view were measured.
6). The photograph was stretched to 2 million times (size: 16.8 cm × 16.8 cm), and the number of laminated molybdenum disulfide layers visible on the photograph was measured.
・ In the microcalorimetry method, a predetermined amount of sample (here, catalyst) is filled in an adsorption tube, ammonia gas is introduced in a certain amount of pulses at a predetermined temperature and adsorbed on the sample, and the adsorption that occurs during this adsorption It is a method of measuring heat and specifying acid strength and acid amount. Here, the heat of adsorption corresponds to the acid strength, and the adsorption amount (introduction amount) corresponds to the acid amount.
In the present invention, the measurement conditions of the microcalorimetry method in which the measurement was performed are as follows.
That is, as a measuring device, a surface analysis device CSA-450G manufactured by Tokyo Riko Co., Ltd. was used, and the catalyst (sample) was vacuum-dried at 400 ° C. for 4 hours, and then the temperature of the thermostatic bath was set to 150 ° C. Then, ammonia gas was introduced and the heat of adsorption was measured using a Tian-Calvet calorimeter.

[Hydrolysis reaction of vacuum gas oil]
The hydrodesulfurization activity of the catalysts obtained in Examples 1 to 6 and Comparative Examples 1 to 5 was evaluated by the following method using vacuum gas oil as the raw material oil.
First, the catalyst was filled into a high-pressure flow reactor to form a fixed bed catalyst layer, and pretreated under the following conditions.
Next, a mixed fluid of the raw material oil and the hydrogen-containing gas heated to the reaction temperature is introduced from the upper part of the reactor, and the desulfurization reaction proceeds under the following conditions. The product oil was separated by a gas-liquid separator.

Catalyst pretreatment conditions:
Pressure (hydrogen partial pressure); 4.9 MPa
Sulfurizing agent; feedstock oil (Arabyanlite vacuum gas oil) in [Hydrolysis reaction of vacuum gas oil]
Temperature: Step temperature rise of 290 ° C. for 15 hours and then 320 ° C. for 15 hours (temperature rise rate is 25 ° C./hr)

Desulfurization reaction conditions:
Reaction temperature: 360 ° C
Pressure (hydrogen partial pressure); 4.9 MPa
Liquid space velocity; 0.66 hr ⁻¹
Hydrogen / oil ratio: 500 m ³ (normal) / Kl

Raw oil properties:
Oil type: Arabian light vacuum gas oil Specific gravity (15/4 ° C); 0.9185
Distillation properties: initial boiling point 349.0 ° C, 50% point 449.0 ° C,
90% point is 529.0 ° C, end point is 566.0 ° C
Sulfur component: 2.45% by mass
Nitrogen component: 0.065% by mass
Pour point: 35 ° C. asphaltene; <100 ppm
Aniline point: 82 ° C

The desulfurization activity was analyzed by the following method.
The reaction apparatus was operated at 360 ° C., and the produced oil was sampled after 20 days. The desulfurization reaction rate constant (Ks) was determined from the sulfur content in the produced oil, the sulfur content of the raw material oil, and the liquid space velocity. The method for obtaining this Ks value is shown below.
The desulfurization reaction rate constant (Ks) is defined as a constant in the reaction rate equation that obtains a reaction order of 1.5 with respect to the amount of reduction in the sulfur content (Sp) of the product oil.
The higher the reaction rate constant, the better the catalytic activity.
Desulfurization reaction rate constant = 2 × [1 / (Sp) ^0.5 −1 / (Sf) ^0.5 ] × (LHSV)
In formula, Sf: Sulfur content (mass%) in raw material oil
Sp: Sulfur content (mass%) in reaction product oil
LHSV: Liquid space velocity (hr ⁻¹ )
Desulfurization specific activity (%) = desulfurization reaction rate constant / desulfurization reaction rate constant of comparative catalyst a × 100

Analysis of the sulfur concentration of the raw material oil and the product oil was obtained with an X-ray sulfur analyzer (RX-610SA) manufactured by Newly Corporation. In addition, it shows that the hydrodesulfurization activity of a catalyst is excellent, so that reaction rate constant is high.
The evaluation results of the catalysts A, B, C, D, E, F, g, h, i, j, and k are shown in Table 3 as relative values when the reaction rate constant of the catalyst g is 100. Further, the amount of carbon deposited on the catalyst after the evaluation was measured. These results are shown in Table 4.

From the results shown in Table 3, it can be seen that the catalyst of the present invention has high hydrodesulfurization activity. On the other hand, the catalyst f carrying only the active metal has a low average layer number and a high adsorption heat of the catalyst, so that the desulfurization activity is poor. After supporting lithium, impregnating liquid containing active metal and organic acid is supported on an alumina carrier, and then calcined to remove carbon, catalyst g has less average number of molybdenum disulfide stacks and hydrodesulfurization. Low activity. Further, the catalyst h excluding only lithium also has a low desulfurization activity due to its high adsorption heat. In addition, since the heat of adsorption of the catalyst is high, a large amount of carbon deposited on the catalyst is also considered as a factor of low desulfurization activity. It can also be seen that the hydrodesulfurization activity of the catalyst f of Comparative Example I having a small specific surface area is low. Finally, it can be seen that the catalyst j having a large amount of lithium supported has a low desulfurization activity because the heat of adsorption of the catalyst is too low.

Claims (5)

10-30% by mass of at least one selected from Group 6 metals of the Periodic Table on the basis of catalyst on an inorganic oxide support, and 1 at least one selected from Group 8 metals of the Periodic Table on an oxide basis Specific surface area of 110 to 300 m ² / g, comprising 15 to 15% by mass, 0.8 to 8% by mass of phosphorus, 2 to 14% by mass of carbon, and 0.1 to 0.8% by mass of lithium. Hydrocarbon oil hydrotreating catalyst having a pore volume of 0.35 to 0.6 m1 / g and an average pore diameter of about 65 to 180 mm. 2. The hydrocarbon oil according to claim 1, wherein the hydrocarbon oil has an acid point which generates an ammonia adsorption heat of 100 to 200 KJ / mol measured by a microcalorimetry method in a range of 270 to 380 μmol per 1 g of the catalyst. Hydroprocessing catalyst. 3. The hydrocarbon oil according to claim 1, wherein the catalyst has an average value of 2.5 to 5 of the number of laminated molybdenum disulfide phases observed by a transmission electron microscope after preliminary sulfidation. 4. Hydroprocessing catalyst. On an inorganic oxide support having a specific surface area of 160 to 500 m ² / g, a pore volume of 0.55 to 0.9 m 1 / g, and an average pore diameter of 60 to 150 mm, at least selected from Group 8 metals of the periodic table A compound containing at least one compound, a compound containing at least one selected from Group 6 metals in the Periodic Table, a solution containing an organic acid, phosphoric acid, and lithium, using a catalyst standard and an oxide equivalent group 6 10-30% by mass of metal, 1-15% by mass of Group 8 metal of the periodic table, 0.8-8% by mass of phosphorus, 0.1-0.8% by mass of lithium, 2-14% by mass of carbon The method for producing a hydrocarbon oil hydrotreating catalyst according to any one of claims 1 to 3, wherein the catalyst is dried at 200 ° C or lower. Contact of a hydrocarbon oil fraction in the presence of the catalyst according to any one of claims 1 to 3 under conditions of a hydrogen partial pressure of 3 to 8 MPa, a temperature of 300 to 420 ° C, and a liquid space velocity of 0.3 to 5 hr- ^1. A method for hydrotreating a hydrocarbon oil, characterized by carrying out a reaction.