JP3924364B2 - Hydrodesulfurization catalyst - Google Patents

Description

【００９１】
【表２】

【００９２】
【発明の効果】
以上のように、本発明の水素化脱硫触媒は、これを用いて、ＶＧＯやＡＲ等の重質油留分を水素化脱硫するとき、水素化脱硫活性を高く維持しながら、長期間にわたって、水素化分解による軽質分の増産が可能である。[0001]
BACKGROUND OF THE INVENTION
  The present invention provides a catalytic hydrodesulfurization of a reduced pressure gas oil (hereinafter referred to as VGO) fraction by an indirect desulfurization apparatus or an atmospheric residue (hereinafter referred to as AR) fraction by a direct desulfurization apparatus. Sulfur compounds can be removed at a high rate for a long time, and the heavy oil fraction can be lightened at a high rate.About hydrodesulfurization catalyst.
[0002]
[Prior art]
  Sulfur compounds are present in high concentration in heavy oil fractions such as VGO, which is a distillate obtained from a vacuum distillation apparatus, and AR, which is a bottom oil when crude oil is processed in an atmospheric distillation apparatus. Therefore, when these heavy oil fractions are used as fuels as they are, a large amount of sulfur oxide (SOx) is discharged into the atmosphere. Sulfur oxide has a harmful effect directly on the human body and is one of the causative substances of acid rain.
[0003]
  Therefore, conventionally, as one of the processes for producing various petroleum products from crude oil, catalytic hydrodesulfurization treatment of heavy oil fractions by indirect desulfurization equipment and direct desulfurization equipment has been incorporated, and in these heavy oil fractions, Removal of sulfur compounds, that is, desulfurization treatment has been carried out, but during this desulfurization, hydrocracking of heavy oil fraction also proceeds at the same time, so higher added value such as naphtha, kerosene, light oil etc. A light fraction is also produced.
[0004]
  Conventionally, a catalyst for hydrodesulfurization treatment aiming to remove sulfur compounds in VGO and AR and at the same time lighten, uses Group VIA metal and Iron group metal as active components. Is supported on an inorganic oxide carrier such as alumina, magnesia, silica, etc., and usually molybdenum is used as the Group VIA metal, and cobalt or nickel is used as the iron group metal. Yes. Here, the Group VIA metal is an essential active component in the hydrodesulfurization catalyst, and it is considered that hydrodesulfurization activity is manifested by sulfiding this into a sulfide.
[0005]
  Furthermore, in order to improve the activity of the desulfurization catalyst as described above, it has been conventionally known that it is effective to add phosphorus, boron or the like to the catalyst (Japanese Patent Laid-Open No. 52-13503). It is also known that the activity can be improved by incorporating zeolite in the carrier (Japanese Patent Laid-Open No. 56-20087).
[0006]
  The catalytic hydrodesulfurization treatment of heavy oil fractions is carried out in the presence of the hydrodesulfurization catalyst as described above in the reactors of indirect desulfurization equipment and direct desulfurization equipment. Along with the increase, a hydrodesulfurization catalyst having high hydrocracking activity of heavy oil has been demanded. In fact, in indirect desulfurization, the MHC process (European Patent No. 0244106) is commercialized in order to increase the production of light fractions.
[0007]
[Problems to be solved by the invention]
  The present inventors have found that in the hydrodesulfurization process, the catalyst surface portion is the main reaction field for the decomposition reaction compared to the desulfurization reaction. Therefore, in order to improve the hydrocracking activity of the conventional heavy oil hydrodesulfurization catalyst, if the active component effective for hydrocracking reaction is coated on the outer surface of the catalyst, the desulfurization activity of the hydrodesulfurization catalyst is increased. As it is, the addition of the active component is limited to the outer surface portion of the catalyst, so that it is possible to use a small amount of additive, suppress the increase in catalyst cost, and improve the hydrocracking activity. The invention has been completed.
[0008]
  That is, the present invention can remove sulfur compounds in the heavy oil fraction at a high rate for a long period of time in the catalytic hydrodesulfurization of VGO by an indirect desulfurization apparatus or AR by a direct desulfurization apparatus, The heavy oil fraction can be lightened at a high rateThe object is to provide a hydrodesulfurization catalyst.
[0009]
[Means for Solving the Problems]
  The hydrodesulfurization catalyst according to the present invention is:
  (a) cobalt3-7 mass% in terms of oxidemolybdenumIs 10-30 mass% in terms of oxide and the balance isaluminaA substrate catalyst comprising:
  (b)Cobalt oxide, nickel oxide, molybdenum oxide and tungsten oxideAt least one metal oxide selected from70~ 100mass% and the restMade of aluminaConsisting of a modified catalyst,
  The modified catalyst is coated on the surface of the base catalyst in a range of 1 to 20 mass parts per 100 mass parts of the base catalyst.
[0010]
  Such a hydrodesulfurization catalyst according to the present invention is obtained by suspending particles of a modified catalyst having a particle size in the range of 10 to 100 μm in water to form a slurry, coating the slurry on a base catalyst, drying, and firing. In the method for producing a desulfurization catalyst in which the modified catalyst is coated on the surface of the base catalyst, preferably, the base catalyst is 1.5 to 5 times in mass ratio with respect to the saturated water absorption amount of the base catalyst. And by using a slurry obtained by suspending the modified catalyst particles in water in an amount in the range of 20 to 200 times by mass with respect to the modified catalyst particles. it can.
[0011]
  Furthermore, the hydrodesulfurization method for heavy oil according to the present invention has a hydrogen partial pressure of 4 to 18 MPa, a temperature of 320 to 410 ° C., and a liquid space velocity of 0.1 to 4.0 hr.^-1The heavy oil is brought into contact with the catalyst under the reaction conditions of
[0012]
DETAILED DESCRIPTION OF THE INVENTION
  The hydrodesulfurization catalyst according to the present invention is:
  (a)cobalt3-7 mass% in terms of oxidemolybdenumIs 10-30 mass% in terms of oxide and the balance isaluminaA substrate catalyst comprising:
  (b)Cobalt oxide, nickel oxide, molybdenum oxide and tungsten oxideAt least one metal oxide selected from70~ 100mass% and the restalumina Consist ofConsisting of a modified catalyst,
  The modified catalyst is coated on the surface of the base catalyst in a range of 1 to 20 mass parts per 100 mass parts of the base catalyst.
[0013]
The hydrodesulfurization catalyst according to the present invention has a multilayer structure comprising a base catalyst which is a granular solid catalyst and a modified catalyst coated on the surface thereof.
[0014]
  In the catalyst having such a multilayer structure, the inorganic oxide carrier in the substrate catalystAlumina is preferably used for.
[0015]
  In the present invention,AluminaAs for, a granular material is used. Such granularaluminaThe shape, specific surface area, pore volume, average pore diameter and the like are not particularly limited, but those having a particle diameter in the range of 0.2 to 5 mm are usually used. Here, the particle diameter means the maximum diameter when the particles are columnar.
[0016]
  Furthermore, in the present invention,aluminaIn order to promote the hydrodesulfurization reaction of VGO and AR, the specific surface area is usually 200 to 400 m.²g^-1In particular, 250-380 m²g^-1It is preferable that it exists in the range. The pore volume is usually 0.4 to 1.2 cm^Threeg^-1In particular, 0.5 to 1.0 cm^Threeg^-1It is preferable that it exists in the range. The average pore diameter is usually in the range of 50 to 130 Å (angstrom), and particularly preferably in the range of 55 to 110 Å.
[0017]
  Similarly, in the preparation of the modified catalyst, when an inorganic oxide support is used,aluminaIs used.
[0018]
  First, preparation of the base catalyst will be described.aluminaIncobaltWhenmolybdenumThe method for preparing the base catalyst, which is a granular solid catalyst in which is supported, is not particularly limited, and can be performed by a conventionally known appropriate method, for example,cobaltWhenmolybdenumThe conventionally known impregnation method, coprecipitation method, kneading method, deposition method, etc.aluminaWhat is necessary is just to make it carry on.
[0019]
  For example, according to the impregnation method,cobaltWith the compoundmolybdenumA solution of the appropriate concentration withaluminaAfter being impregnated and dried, in air, the temperature is in the range of 350 to 700 ° C., preferably 400 to 600 ° C., but is not limited, but usually by firing for about 1 to 10 hours A substrate catalyst which is a granular solid catalyst can be prepared. The calcination temperature in air is about 350 to 700 ° C., preferably about 400 to 600 ° C., and the time is about 1 to 10 hours.
[0020]
  But if necessary, firstaluminaIncobaltImpregnated with a solution of the appropriate concentration of the compound of, dried, calcined in air and then treated in this wayaluminaThemolybdenumIt may be impregnated with a solution of an appropriate concentration of the above compound, dried, and calcined in air.aluminaInmolybdenumAfter loadingcobaltMay be supported.
[0021]
  According to the present invention, in the preparation of the substrate catalyst,Can be usedExamples of the cobalt compound include cobalt nitrate, cobalt sulfate, cobalt carbonate, cobalt acetate, cobalt oxalate, and cobalt chloride.TheAlso,Can be usedSpecific examples of the molybdenum compound include ammonium molybdate, molybdenum oxide, molybdenum condensed acid salt, and the like.
[0022]
  Mentioned abovecobaltas well asmolybdenumIn general, an aqueous solution is preferably used as the compound solution. Therefore, an acidic solution such as phosphoric acid may be added to the aqueous solution in order to enhance the water solubility of the compound in the aqueous solution. Here, taking phosphoric acid as an example, various materials such as orthophosphoric acid, metaphosphoric acid, triphosphoric acid, and tetraphosphoric acid are used. Further, as a solvent for the solution of the above compound, various solvents such as alcohols, ethers, ketones, aqueous solutions thereof, aromatic hydrocarbons and the like can be used alone or in a mixture of two or more in addition to water. Can also be used.
[0023]
  the abovecobaltas well asmolybdenumEach amount in the solution of the compound ofcobalt3-7 mass% in terms of oxide, preferably 4-6 mass%,molybdenumIs 10-30 mass% in terms of oxide, preferably 13-23 mass%,aluminaIs used as the balance.
[0024]
  As mentioned above,the aboveWhen phosphoric acid is added to the aqueous solution of the compound, phosphoric acid is added to the base catalyst, P₂O_Five It is used so as to be 0.1 to 4 mass%, preferably 1 to 3 mass% in terms of conversion. The amount of phosphoric acid is included in the amount of carrier.
[0025]
  In the present invention, in the substrate catalystcobaltWhen the component is less than 3 mass%, the resulting catalyst is not sufficient in the required hydrodesulfurization catalyst activity, while when it exceeds 7 mass%,ThatIn the state of the compound (sulfide) under the use conditions, it seems that it is difficult to maintain a high dispersion state, but remarkable sintering (sintering) occurs, and the catalytic activity tends to decrease. Similarly,molybdenumWhen the component is less than 10 mass%, the resulting catalyst is not sufficient in the required hydrodesulfurization catalyst activity,molybdenumIngredientsThatIn the state of the compound (sulfide) under use conditions, the cobaltcomponentHowever, when it exceeds 30 mass%, sintering (sintering) occurs similarly, and the specific surface area of the catalyst is reduced, resulting in high catalytic activity. Can't get.
[0026]
  In the present invention, as described above, the base catalyst is a granular solid catalyst, and its shape is particularly limited as long as no pressure difference is generated before and after the catalyst layer under the reaction conditions. However, in consideration of the flow of the catalyst layer of heavy oil fractions such as VGO and AR, it is preferable that the particle size is in the range of 0.2 to 5 mm. Here, the particle diameter means the maximum diameter when the particles are columnar.
[0027]
  In particular, according to the present invention, it is desirable that the base catalyst has a so-called pellet shape such as a columnar shape, a trilobal column shape, or a quadrilobal column shape, and further, a pressure difference does not occur before and after the catalyst layer under reaction conditions. The pellet diameter is preferably in the range of 1/10 to 1/36 inch. Here, the pellet diameter is the length of the thickest part except that the shape of the pellet is a cylinder.
[0028]
  The hydrodesulfurization catalyst according to the present invention is formed on the surface of the base catalyst as described above.Cobalt oxide, nickel oxide, molybdenum oxide and tungsten oxideIt can be obtained by coating a modified catalyst comprising at least one metal oxide selected from
[0029]
  The preparation method of this modified catalyst is not particularly limited, and any conventionally known method such as impregnation method, coprecipitation method, kneading method, deposition method, ion exchange method, heat exchange method, etc. It can be prepared by various methods such as a decomposition method. In addition, as the compound species used for the preparation, various kinds of compounds as described above can be used depending on the method for preparing the modified catalyst.Cobalt compounds andMolybdenum compounds are used.As the nickel compound, for example, nickel nitrate, nickel sulfate, nickel carbonate, nickel acetate, nickel oxalate, nickel chloride and the like are used. Specific examples of the tungsten compound include ammonium tungstate, tungsten oxide, tungsten condensed acid salt, and the like.
[0030]
  For example,Cobalt oxide, nickel oxide, molybdenum oxide and tungsten oxideThe modified catalyst consisting only of at least one metal oxide selected from the above can be obtained by firing various compounds that produce the oxide by firing at high temperature in air.
[0031]
  On the other hand, with the above metal oxidealuminaThe modified catalyst consisting of can be prepared, for example, by an impregnation method.
[0032]
  To prepare the modified catalyst by the impregnation method, for example,aluminaAfter impregnating with a solution of the modifying compound, it may be fired in air. This firing temperature is usually in the range of 400 to 700 ° C., preferably 450 to 600 ° C., and the firing time is usually about 1 to 10 hours. There is no significant difference in the catalyst performance whether or not the reduction treatment with hydrogen or the like after calcination is performed.
[0033]
  The amount of the modified metal constituting the modified catalyst is as follows:It is in the range of 70 to 100 mass% of the total amount in terms of oxide..
[0034]
  In the modified catalyst, the amount of the modified metal70When it is less than mass%, the effect of enhancing the hydrocracking activity of the catalyst can hardly be obtained in the resulting hydrodesulfurization catalyst.
[0035]
  In order to coat the modified catalyst on the surface of the base catalyst, it is necessary to pulverize the particle size to a range of 10 to 100 μm, preferably 30 to 80 μm. It is difficult to pulverize the modified catalyst into fine particles having a particle size of less than 10 μm. On the other hand, when the modified catalyst is a particle having a particle size of more than 100 μm, the coating effect, that is, the coated modified catalyst particles and the substrate catalyst In addition to the effect of improving the concerted or cooperative decomposition activity, the coated modified catalyst tends to peel off from the surface of the substrate catalyst.
[0036]
  In order to coat the surface of the base catalyst with the modified catalyst, the fine particles of the modified catalyst are suspended in water to form a slurry, and this slurry is applied to the surface of the base catalyst and dried. Repeatedly, the resulting hydrodesulfurization catalyst has a predetermined ratio of the base catalyst and the modification catalyst.
[0037]
  In the hydrodesulfurization catalyst according to the present invention, the modifying catalyst is 1 to 20 mass parts, preferably 1 to 10 mass parts, particularly preferably 2 to 8 mass parts per 100 mass parts of the base catalyst. When the amount of the modified catalyst is less than 1 mass part per 100 mass parts of the base catalyst, the effect of enhancing the hydrocracking activity of the catalyst can hardly be obtained.
[0038]
  According to the present invention, when the fine particles of the modified catalyst are suspended in water, the amount of water used for suspending the fine particles of the modified catalyst is the maximum mass of water that can be absorbed by the base catalyst (hereinafter simply referred to as “water”). The ratio of the mass of water used to suspend the fine particles of the modified catalyst / the mass of the modified catalyst to be coated is 20 to The amount is preferably in the range of 200.
[0039]
  For example, when coating 2.5 g of the modified catalyst (5 mass parts with respect to 100 mass parts of the base catalyst) with respect to 50 g of the base catalyst (water absorption amount 30 g), the amount of water satisfying the above requirements (fine particles of the modified catalyst) The amount of water used to suspend the water) is in the range of 50 to 150 g. The reason for this definition of the amount of water used to suspend the fine particles of the modified catalyst is that when the concentration of the slurry is too high, the slurry cannot be uniformly coated on the substrate catalyst. This is because the coating operation needs to be repeated unnecessarily many times when the concentration of is too small.
[0040]
  The slurry in which the fine particles of the modified catalyst are suspended preferably contains silica sol, alumina sol, zirconia sol or the like as a binder in the resulting hydrodesulfurization catalyst so that the modified catalyst is not easily separated from the base catalyst. The amount of such a binder is usually in the range of 2 to 20 mass parts, preferably 5 to 15 mass parts with respect to 100 mass parts of water in the slurry. When the amount of the binder is less than 2 mass parts with respect to 100 mass parts of water in the slurry, the effect as a binder is not sufficient, while when more than 20 mass parts, not only the modified catalyst but also the base catalyst As a result of being coated with the oxide constituting the binder, not only the desulfurization activity is lowered, but also the viscosity of the slurry is high and the coating operation is difficult.
[0041]
  In order to charge the hydrodesulfurization catalyst according to the present invention to the reactor of the indirect desulfurization apparatus or the direct desulfurization apparatus and use it for the catalytic hydrodesulfurization of heavy oil, the reactor filled with the catalyst is used as a raw material oil as in the conventional case. The heavy oil may be introduced and treated under conditions of conventionally known high temperature and high pressure and a substantial hydrogen partial pressure.
[0042]
  Most commonly, the hydrodesulfurization catalyst according to the present invention is maintained in the reactor as a fixed bed, and the fixed oil is passed through the fixed bed from above to below. The catalyst may be used by being charged into a single reactor, or each of a plurality of reactors connected in series may be charged with the catalyst. In particular, when the feedstock is AR, since AR contains a high concentration of metal such as nickel and vanadium, a multistage reactor in which a hydrodesulfurization catalyst is combined with a catalyst system having a demetallizing function is used. It is preferable to use it.
[0043]
  The reaction conditions are not particularly limited. For example, a vacuum gas oil (VGO) fraction having a 5% by volume distillation temperature of 240 ° C or higher and a 95% by volume distillation temperature of 450 ° C or higher, or 40 volumes. When the atmospheric residual oil (AR) having a% distillation temperature of 450 ° C. or higher is subjected to catalytic hydrodesulfurization using the hydrodesulfurization catalyst according to the present invention, the hydrogen partial pressure is 4 to 18 MPa, preferably 4.5 to 16 MPa. The raw material oil temperature is 320 to 410 ° C., preferably 350 to 405 ° C., and the liquid space velocity is 0.1 to 4.0 hr.^-1, Preferably 0.15 to 2.0 hr^-1The contact with the catalyst according to the present invention may be performed under the conditions of the following range.
[0044]
  When hydrodesulfurization of the above heavy oil is performed under such reaction conditions, the decomposition rate of the hydrodesulfurization catalyst according to the present invention is significantly higher than that of the conventional hydrodesulfurization catalyst. The light component yield can be improved by 1.0% or more. This is worth improving the yield of light components of about 10,000 kL / year in a device with a nominal capacity of 2800 kL / day.
[0045]
  Thus, according to the present invention, the activity of the hydrocracking reaction can be enhanced while the high activity of the hydrodesulfurization reaction is maintained by coating the surface of the base catalyst with a modified catalyst having a high hydrogenation resolution. Thus, it is possible to achieve an increase in production of light components while removing sulfur compounds in the heavy oil fraction at a high rate over a long period of time.
[0046]
  Furthermore, the hydrodesulfurization catalyst according to the present invention also has a feature that the initial hydrodesulfurization activity is higher than that of the conventional catalyst, so that the 90 vol% distillation temperature at which catalyst deterioration is not significant is 250 ° C. or less. Can be effectively used for hydrodesulfurization of a kerosene fraction and a gas oil fraction having a 90% by volume distillation temperature of 400 ° C. or lower.
[0047]
【Example】
  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.
[0048]
(Preparation of substrate catalyst A)
Base catalyst A1
(Preparation of 5 mass% CoO-15 mass% MoO3 supported alumina (cylindrical pellet))
  An aqueous solution in which 10 g of molybdophosphoric acid 30 hydrate, 1.85 g of orthophosphoric acid and 8.0 g of cobalt acetate tetrahydrate are dissolved in 25 g of ion-exchanged water is cylindrical (1/16 inch) alumina pellet (manufactured by Nippon Ketjen) , Surface area 385m²g^-1) Impregnated in 36 g, dried at room temperature, calcined at 500 ° C. for 3 hours, and 5 mass% CoO-15 mass% MoO_Three A supported alumina was obtained.
[0049]
Substrate catalyst A2
(5 mass% CoO-15 mass% MoO_Three Preparation of supported alumina (four-leaf pellet)
  In the preparation of the substrate catalyst A1, instead of the columnar (1/16 inch) alumina pellets, four-leaf (1/20 inch) alumina pellets (manufactured by Nippon Ketjen Co., Ltd., surface area of 378 m)² g^-15 mass% CoO-15 mass% MoO in the same manner as the base catalyst A1 except that_Three A supported alumina was obtained.
[0050]
Substrate catalyst A3
(5 mass% CoO-20 mass% MoO_Three Preparation of supported alumina)
  In the preparation of the substrate catalyst A1, 5 mass% CoO-20 mass% was obtained in the same manner as the substrate catalyst A1, except that 13.3 g of molybdophosphoric acid 30 hydrate and 33.5 g of cylindrical (1/16 inch) alumina pellets were used. MoO_Three A supported alumina was obtained.
[0051]
Substrate catalyst A4
(2 mass% CoO-15 mass% MoO_Three Preparation of supported alumina)
  In the preparation of the base catalyst A1, 2 mass% CoO-15 mass% was the same as the base catalyst A1 except that 3.2 g of cobalt acetate tetrahydrate and 37.7 g of cylindrical (1/16 inch) alumina pellets were used. MoO_Three A supported alumina was obtained.
[0052]
Substrate catalyst A5
(8 mass% CoO-15 mass% MoO_Three Preparation of supported alumina)
  In the preparation of the base catalyst A1, 8 mass% CoO-15 mass% was the same as the base catalyst A1 except that 12.8 g of cobalt acetate tetrahydrate and 34.6 g of cylindrical (1/16 inch) alumina pellets were used. MoO_Three A supported alumina was obtained.
[0053]
Substrate catalyst A6
(5 mass% CoO-8 mass% MoO_Three Preparation of supported alumina)
  In the preparation of the base catalyst A1, 5 mass% CoO-8 mass% was the same as the base catalyst A1 except that 5.3 g of molybdophosphoric acid 30 hydrate and 39.4 g of cylindrical (1/16 inch) alumina pellets were used. MoO_Three A supported alumina was obtained.
[0054]
Substrate catalyst A7
(5 mass% CoO-35 mass% MoO_Three Preparation of supported alumina)
  In the preparation of the base catalyst A1, 5 mass% CoO-35 mass% was the same as the base catalyst A1 except that 23.3 g of molybdophosphoric acid 30 hydrate and 28.7 g of cylindrical (1/16 inch) alumina pellets were used. MoO_Three A supported alumina was obtained.
[0055]
(Preparation of modified catalyst B)
Modified catalyst B1
(Preparation of molybdenum oxide)
  Ammonium molybdate ((NH_Four)₆Mo₇O_{twenty four}・ 4H₂50 g of O (molecular weight = 1236)) was calcined at 500 ° C. for 3 hours to obtain molybdenum oxide.
[0056]
Modified catalyst B2
(Preparation of tungsten oxide)
  Tungstic acid (H₂WO_Four(Molecular weight = 250)) 50 g was calcined at 500 ° C. for 3 hours to obtain tungsten oxide.
[0057]
Modified catalyst B3
(Preparation of cobalt oxide)
  Cobalt nitrate hexahydrate (Co (NO_Three)₂・ 6H₂50 g of O (molecular weight = 291)) was baked at 500 ° C. for 3 hours to obtain cobalt oxide.
[0058]
Modified catalyst B4
(Preparation of nickel oxide)
  Nickel nitrate hexahydrate (Ni (NO_Three)₂・ 6H₂50 g of O (molecular weight = 291)) was baked at 500 ° C. for 3 hours to obtain nickel oxide.
[0059]
Modified catalyst B5
(80 mass% MoO_Three Preparation of supported alumina)
  Molybdophosphoric acid ((NH_Four)₆Mo₇O_{twenty four}・ NH₂An aqueous solution prepared by dissolving 29.3 g of O (n = about 30)) in 50 g of ion-exchanged water is a cylindrical (1/16 inch) alumina pellet (manufactured by Nippon Ketjen, surface area of 385 m²・ G^-1) 5.4 g was impregnated until the amount of water absorption was reached, and dried at room temperature. This operation was repeated several times until the aqueous solution disappeared, and calcined at 500 ° C. for 3 hours to obtain 80 mass% MoO._Three A supported alumina was obtained.
[0060]
Modified catalyst B6
(5 mass% MoO_Three Preparation of supported alumina)
  Molybdophosphoric acid ((NH_Four)₆Mo₇O_{twenty four}・ NH₂An aqueous solution obtained by dissolving 3.8 g of O (n = about 30) in 35 g of ion-exchanged water was used as a cylindrical (1/16 inch) alumina pellet (manufactured by Nippon Ketjen, surface area of 385 m²・ G^-1) 53.5 g impregnated and dried at room temperature, then calcined at 500 ° C. for 3 hours, and 5 mass% MoO_Three A supported alumina was obtained.
[0061]
(Raw oil)
  The feedstocks used in the following examples and comparative examples are as follows.
[0062]
Raw material oil R1 (vacuum gas oil (VGO))
    Raw oil: Arabian heavy
    Density: 0.8990 g · cm^-3(15 ° C)
    Sulfur content: 3.06 mass%
    Metal content (Ni and V): 1.3 mass ppm
    Distillation properties: Distillation temperature
                5% by volume = 306 ° C
              50% by volume = 404 ° C
              95% by volume = 510 ° C.
[0063]
Feedstock R2 (Atmospheric residual oil (AR))
    Raw oil: Arabian light
    Density: 0.9724 g · cm^-3(15 ° C)
    Sulfur content: 3.25 mass%
    Metal content (Ni and V): 88 mass ppm
    Distillation properties: Distillation temperature
                5% by volume = 404 ° C
              40% by volume = 493 ° C
              54% by volume = 538 ° C
[0064]
(Reaction conditions)
  The reaction conditions used in the following examples and comparative examples are as follows.
[0065]
Reaction condition P1
  Hydrogen partial pressure: 4.9 MPa
  Reaction temperature: 400 ° C
  Liquid space velocity: 0.66 hr^-1
  Hydrogen / oil ratio: 422Nm^ThreekL^-1
(Note) This reaction condition is for hydrodesulfurization treatment of VGO fraction.
[0066]
Reaction condition P2
  Hydrogen partial pressure: 10.3 MPa
  Reaction temperature: 390 ° C
  Liquid space velocity: 0.4 hr^-1
  Hydrogen / oil ratio: 997 Nm^ThreekL^-1
(Note) This reaction condition is for hydrodesulfurization treatment of AR fraction.
[0067]
(Evaluation of hydrodesulfurization activity of catalyst)
  The hydrodesulfurization activity of the catalyst was evaluated by the reaction rate constant k value derived from the following formula. Here, the higher the k value, the better the catalytic activity.
[0068]
  k = [(1 / S concentration of produced oilⁿ)-(1 / Raw oil S concentrationⁿ) X liquid space velocity
[0069]
  Here, when the raw material oil is VGO, n = 0.5, and when AR, n = 1.
[0070]
(Evaluation of hydrocracking activity of catalyst)
  The hydrocracking activity of the catalyst was judged by the relative yield of a fraction below 343 ° C. obtained by gas chromatography distillation according to ASTM D2887. The higher the cracking activity, the higher the yield of light fractions of 343 ° C. or lower.
[0071]
  Hereinafter, examples in which the raw material oil was hydrodesulfurized and decomposed under the above reaction conditions using a hydrodesulfurization catalyst M obtained by coating the surface of the base catalyst with a modification catalyst will be shown together with comparative examples.
[0072]
Example 1
  The modified catalyst B1 (1.0 g) having a particle size of 55 to 73 μm is suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol, and this is suspended in the base catalyst A1 (50 g, saturated water absorption 30 g). The hydrodesulfurization catalyst M1 was prepared by coating. Using 10 g of this hydrodesulfurization catalyst, the feed oil R1 was subjected to catalytic hydrodesulfurization under reaction conditions P1. The results are shown in Table 1.
[0073]
Example 2
  The modified catalyst B2 (1.0 g) having a particle size of 55 to 73 μm was suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol, and this was suspended in the base catalyst A1 (50 g, saturated water absorption 32 g). The hydrodesulfurization catalyst M2 was prepared by coating. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 1.
[0074]
Example3
  Modified catalyst B sized to 55-73 μm3(1.0 g) was suspended in 100 g of silica-sol-containing ion-exchanged water containing 90 g of ion-exchanged water and 10 g of silica sol, and this was coated on the base catalyst A1 (50 g, saturated water absorption 30 g).3Was prepared. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 1.
[0075]
Example4
  Modified catalyst B sized to 55-73 μm4(1.0 g) was suspended in 100 g of silica-sol-containing ion-exchanged water containing 90 g of ion-exchanged water and 10 g of silica sol, and this was coated on the base catalyst A1 (50 g, saturated water absorption 30 g).4Was prepared. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 1.
[0076]
Example5
  Modified catalyst B sized to 55-73 μm5(1.0 g) was suspended in 100 g of silica-sol-containing ion-exchanged water containing 90 g of ion-exchanged water and 10 g of silica sol, and this was coated on the base catalyst A1 (50 g, saturated water absorption 30 g).5Was prepared. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 1.
[0077]
Example6
  Using 10 g of the desulfurization catalyst M1 prepared in Example 1, the feed oil R2 was subjected to catalytic hydrodesulfurization under the reaction condition P2. The results are shown in Table 1.
[0078]
Comparative Example 1
  Modified catalyst B sized to 55-73 μm6(1.0 g) was suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol, and this was coated on the base catalyst A1 (50 g, saturated water absorption 30 g) to prepare a desulfurization catalyst K1. . Using 10 g of this desulfurization catalyst, the feed oil R1 was subjected to catalytic hydrodesulfurization under reaction conditions P1. The results are shown in Table 1.
[0079]
Comparative Example 2
  The modified catalyst B1 (0.25 g) sized to 55 to 73 μm was suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol, and this was suspended in the base catalyst A1 (50 g, saturated water absorption 30 g). Coating was performed to prepare a desulfurization catalyst K2. Using 10 g of this desulfurization catalyst, the feed oil R1 was subjected to catalytic hydrodesulfurization under reaction conditions P1. The results are shown in Table 1.
[0080]
Comparative Example 3
  The modified catalyst B1 (14 g) sized to 55 to 73 μm is suspended in 300 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol, and this is coated on the base catalyst A1 (50 g, saturated water absorption 30 g). Thus, a desulfurization catalyst K3 was prepared. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 1.
[0081]
Example7
  The modified catalyst B1 (1.0 g) having a particle size of 55 to 73 μm was suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol, and this was suspended in the base catalyst A2 (50 g, saturated water absorption 32 g). A desulfurization catalyst N1 was prepared by coating. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 2.
[0082]
Example8
  The modified catalyst B1 (1.0 g) having a particle size of 55 to 73 μm was suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol.3(50 g, saturated water absorption 25 g)2Was prepared. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 2.
[0083]
Example9
  Example7Using 10 g of the desulfurization catalyst N1 prepared in Step 1, the catalytic hydrodesulfurization was performed on the raw material oil R2 under the reaction condition P2. The results are shown in Table 2.
[0084]
Comparative Example 4
  The modified catalyst B1 (1.0 g) having a particle size of 55 to 73 μm was suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol.4(50 g, saturated water absorption 34 g) was coated to prepare a desulfurization catalyst L1. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 2.
[0085]
Comparative Example 5
  The modified catalyst B1 (1.0 g) having a particle size of 55 to 73 μm was suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol.5A desulfurization catalyst L2 was prepared by coating (50 g, saturated water absorption 28 g). Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 2.
[0086]
Comparative Example 6
  The modified catalyst B1 (1.0 g) having a particle size of 55 to 73 μm was suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol.6(50 g, saturated water absorption 22 g) was coated to prepare a desulfurization catalyst L3. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 2.
[0087]
Comparative Example 7
  The modified catalyst B1 (1.0 g) having a particle size of 55 to 73 μm was suspended in 100 g of silica sol-containing ion exchange water containing 90 g of ion exchange water and 10 g of silica sol.7(50 g, saturated water absorption 18 g) was coated to prepare a desulfurization catalyst L4. Using 10 g of this desulfurization catalyst, catalytic hydrodesulfurization of raw material oil R1 was performed under reaction conditions P1. The results are shown in Table 2.
[0088]
Comparative Example 8
  Using 10 g of the base catalyst A1, the feed oil R1 was subjected to catalytic hydrodesulfurization under the reaction conditions P1. The results are shown in Table 2.
[0089]
Comparative Example 9
  Using 10 g of the base catalyst A1, the feedstock oil R2 was subjected to catalytic hydrodesulfurization under the reaction conditions P2. The results are shown in Table 2.
[0090]
[Table 1]

[0091]
[Table 2]

[0092]
【The invention's effect】
  As described above, when the hydrodesulfurization catalyst of the present invention is used to hydrodesulfurize heavy oil fractions such as VGO and AR, the hydrodesulfurization activity is maintained high, over a long period of time. Light production can be increased by hydrocracking.

Claims (3)

(a) a base catalyst in which cobalt is 3 to 7 mass% in terms of oxide, molybdenum is 10 to 30 mass% in terms of oxide, and the balance is alumina;
(b) at least one metal oxide selected from cobalt oxide, nickel oxide, molybdenum oxide and tungsten oxide is composed of 70 to 100 mass% in terms of oxide and the modified catalyst composed of alumina as the balance;
A hydrodesulfurization catalyst, wherein the surface of the base catalyst is coated with the modified catalyst in a range of 1 to 20 mass parts per 100 mass parts of the base catalyst.   2. The hydrodesulfurization catalyst according to claim 1, wherein the modifying catalyst comprises 100 mass% of at least one metal oxide selected from cobalt oxide, nickel oxide, molybdenum oxide, and tungsten oxide.   The hydrodesulfurization catalyst according to claim 1 or 2, wherein the metal oxide in the modification catalyst is at least one selected from molybdenum oxide and tungsten oxide.