JPH06127931A - Silica-alumina, its production and catalyst for hydrogenation - Google Patents

Abstract

PURPOSE:To improve the hydrogenation desulfurization activity for light and heavy oils an the uniform dispersibility of deposited hydrogenation metal in silica-alumina by specifying the structure, silica content, a pore volume and the total surface area with respect to the catalyst. CONSTITUTION:The alumina-silica has the structure where a silica layer is formed on the surface of alumina as a nucleus and contains silica by 10-20wt.%. It has the 1st peak of the pore volume distribution in the range of 30-300A pore diameter by a nitrogen absorption method and it has the 2nd peak in the range of 300-1500A pore diameter by a mercury forcible feeding method. The volume A of pores of 30-300A diameter including the 1st peak is in the range of 80% of the volume B of pores of 0-300A diameter by the nitrogen absorption method. Further the volume C of pores of 300-1500A diameter including the 2nd peak is in the range of 15-40% of the volume D of pores of 0-1500A diameter and the volume E of pores of 150-150000A diameter by the mercury forcible feeding method is in the range of 0.3-0.9ml/g and the alumina-silica has the total surface area of >=250m<2>/g.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to silica-alumina, a method for producing the same, and a catalyst for hydrotreating hydrocarbon oils using silica-alumina as a carrier.

[0002]

2. Description of the Related Art Various types of catalysts for hydrotreating hydrocarbon oils have been proposed. Among them, atmospheric distillation treated oils or distillate oils under reduced pressure distillation, residual oils and mixtures thereof As a catalyst having a relatively excellent performance as an oil hydrorefining catalyst, there is one in which a hydrogenation-active metal component is supported on an alumina-containing carrier containing silica having a specific pore volume distribution. 3-31496). This known catalyst has a pore distribution in both micropores with a pore diameter of 300 Å or less and macropores with a pore diameter of more than 300, and has excellent performance in both hydrodesulfurization and hydrodenitrogenation reactions. Have. However, according to the studies by the present inventors, in the case of this catalyst, it is still unsatisfactory in terms of hydrodesulfurization activity of heavy oil, and the homogeneous dispersion of the supported hydrogenation active metal component on the carrier is carried out. In terms of sex, it turned out to be unsatisfactory.

[0003]

The present invention solves the above problems found in the prior art and has excellent hydrodesulfurization activity not only for light oils but also for heavy oils,
It is an object of the present invention to provide a hydrotreating catalyst excellent in uniform dispersibility of a supported metal hydride component, silica-containing alumina as a catalyst carrier thereof, and a method for producing the same.

[0004]

The present inventors have completed the present invention as a result of intensive studies to solve the above problems. That is, according to the present invention, it has a structure in which a silica layer is formed on the surface of alumina as a core,
It is a silica-alumina containing 0 to 20% by weight, and the first peak of the pore volume distribution is in the range of 30 to 300 Å as measured by the nitrogen adsorption method, and the pore diameter measured by the mercury penetration method is While having the second peak of the pore volume distribution in the range of 300 to 1500Å, the volume A of the pores having the diameter of the range of 30 to 300Å including the first peak is in the range of 0 to 300Å measured by the nitrogen adsorption method. It is 80% or more of the volume B of the pores having a diameter, and the volume C of the pores having a diameter in the range of 300 to 1500Å including the second peak is 15 of the volume D of the pores having a diameter of 0 to 1500Å.
The volume E of the pores having a diameter in the range of 150 to 150000Å as measured by the mercury penetration method is in the range of 0.3 to 0.9 ml / g, and the total surface area is 250 m ² Silica-alumina is provided which is characterized by being / g or more.

Further, according to the present invention, at least one hydrogenation is carried out on a silica-alumina-containing carrier having a structure in which a silica layer is formed on the surface of alumina as a nucleus and containing 10 to 20% by weight of silica. A catalyst supporting an active metal component, wherein the pore diameter measured by a nitrogen adsorption method is 30 to
The first peak of the pore volume distribution is in the range of 300Å, and the second peak of the pore volume distribution is in the range of 300 to 1500Å where the pore diameter measured by mercury porosimetry is
The volume A of the pores having a diameter in the range of 30 to 300Å including the peak is 80% or more of the volume B of the pores having a diameter in the range of 0 to 300Å measured by the nitrogen adsorption method, and the second peak is The volume C of the pores having a diameter in the range of 300 to 1500 Å is in the range of 15 to 40% of the volume D of the pores having a diameter of 0 to 1500 Å, and in the range of 150 to 150,000 Å measured by mercury porosimetry. There is provided a hydrotreating catalyst characterized in that the volume E of pores having a diameter is in the range of 0.3 to 0.9 ml / g and the total surface area is 250 m ² / g or more.

Furthermore, according to the present invention, in the method for producing silica-alumina, an acidic aluminum aqueous solution is added to a sodium hydroxide aqueous solution having a pH range of 7 to 13.
A step of adding and mixing within 5 seconds, maintaining the mixed solution at 60 to 80 ° C. to precipitate alumina hydrate, and adding and mixing an aqueous solution of a water-soluble silicon compound to an aqueous solution containing the precipitate of alumina hydrate. However, under the condition of pH 7-10, temperature 60-
There is provided a method for producing silica-alumina, which comprises the step of depositing silica hydrate on an alumina hydrate precipitate while maintaining the temperature at 80 ° C.

In the hydrotreating catalyst of the present invention, a silica-alumina carrier having a structure in which a silica layer is formed on the surface of alumina as a nucleus is used as a catalyst carrier. The content of silica in this catalyst is to control the increase of hydrogen consumption or the production of coke due to the excessive decomposition reaction in the hydrodesulfurization reaction or the hydrodenitrogenation reaction,
It is preferable to set it in the range of 10 to 20% by weight. In addition to silica, this alumina may contain one or more kinds of other refractory inorganic oxides such as magnesia, calcium oxide, zirconia, titania, boria, hafnia and crystalline zeolite. In this case, silica acts to control the solid acidity required for the catalyst,
The specific addition amount is appropriately determined according to the desired catalyst acid strength. Silica imparts a strong acid point to the catalyst and increases the hydrocarbon decomposition activity of the catalyst, while, for example, magnesia reduces the strong acid point of alumina-silica, etc.
At the same time, it has the effect of increasing the weak acid point and improving the selectivity of the catalyst. The content of the refractory inorganic oxide such as magnesia, calcium oxide, zirconia, titania, boria, hafnia and crystalline zeolite is appropriately in the range of about 1 to 10% by weight based on alumina-silica. As the alumina, one forming γ-alumina, χ-alumina or η-alumina or a mixture thereof is suitable.

In order to produce silica-alumina suitable as the catalyst carrier of the present invention, first, an alkaline aqueous solution adjusted to pH 7 to 13, preferably 11 to 12.5 is prepared.
As the alkali, sodium hydroxide, potassium hydroxide, ammonium hydroxide or the like is used. The alkali concentration in the aqueous solution is usually 25 to 35% by weight, preferably 2
It is 8 to 30% by weight. In the present invention, an acidic aluminum compound aqueous solution is added to and mixed with this alkaline aqueous solution. As the acidic aluminum compound, aluminum sulfate, chloride, nitrate and the like are used. The concentration of the acidic aluminum compound in the aqueous solution is usually 36 to 42.
%, Preferably 38-40% by weight. In this case, the pH of the mixed aqueous solution is 7 to 11, preferably 7-1.
It is 0. In the present invention, the addition of the acidic aluminum compound aqueous solution to the alkaline aqueous solution is performed as quickly as possible. Generally, the addition of the acidic aluminum aqueous solution to the alkaline aqueous solution is completed within 45 seconds, preferably within 30 seconds.

The mixed aqueous solution obtained as described above is
This is maintained at a temperature of 60 to 80 ° C, preferably 65 to 75 ° C. The holding time in this case is at least 0.5 hour, preferably 1 to 2 hours. As a result, precipitation (gel) of alumina hydrate occurs in the mixed aqueous solution. Since the precipitation of the alumina hydrate in this case is formed by adding and mixing the acidic aluminum compound aqueous solution to the alkaline aqueous solution in a short time as described above, the alumina hydrate is entirely hydrated in the mixed aqueous solution. The product is a cotton-like precipitate uniformly dispersed.

In the present invention, next, an aqueous solution of a water-soluble silicon compound is added and mixed to the mixed aqueous solution containing such a precipitate of alumina hydrate. As the water-soluble silicon compound, alkali metal silicate, tetraalkoxysilane, orthosilicate ester, etc. are used. As the alkali metal silicate, it is preferable to use sodium silicate having a molar ratio of Na ₂ O: SiO ₂ in the range of 1: 2 to 1: 4. The concentration of the silicon compound in the aqueous solution is 5 to 10
% By weight, preferably 6-8% by weight. The amount of the silicon compound added to the aqueous solution containing the alumina hydrate precipitate is an amount corresponding to the composition of the silica-containing alumina as the final product, and the silica content in the silica-alumina is 1
The amount is 0 to 20% by weight. The pH of the mixed solution of the aqueous solution containing the precipitate of alumina hydrate and the aqueous solution of the silicon compound is maintained at pH 7 to 11, preferably 7 to 10. In this case, if necessary, a pH adjuster such as an aqueous solution of mineral acid is added to maintain the pH of the mixed aqueous solution within the above range. This mixed aqueous solution is maintained at a temperature of 60 to 80 ° C, preferably 65 to 75 ° C. The holding time is at least 0.5 hour, preferably 1-2 hours. By this operation, precipitated particles obtained by depositing silica hydrate on alumina hydrate are obtained. The precipitated particles are separated from the liquid, and then subjected to a conventional washing treatment, for example, a washing treatment using an aqueous solution of ammonium carbonate and water to remove impurity ions, and then a drying and firing treatment. Drying is performed at room temperature to 200 ° C. in the presence or absence of oxygen. The firing is performed at 200 to 800 ° C, preferably 550 to 650 ° C in the presence of oxygen. In this way, it is possible to obtain silica-alumina having a structure in which a silica layer is formed on the surface of an alumina core and having the following specific characteristics. (1) 250 m ² / g or more, especially 255 to 350 m ² / g
Has a total surface area of. (2) Pore diameter of 30 to 30 measured by nitrogen adsorption method
It has the first peak of the pore volume distribution in the range of 0Å. (3) Pore diameter measured by mercury porosimetry is 300 to 1
It has a second peak of the pore volume distribution in the range of 500Å. (4) The volume A of pores having a diameter of 30 to 300Å including the first peak is 80% or more of the volume B of pores having a diameter of 0 to 300Å measured by a nitrogen adsorption method, and particularly,
It is in the range of 80 to 95%. (5) The volume C of pores having a diameter in the range of 300 to 1500Å including the second peak is 15 to 40%, preferably 15 to 40% of the volume D of pores having a diameter of 0 to 1500Å.
It is in the range of 30%. (6) 150-150,000 measured by mercury porosimetry
The volume E of pores having a diameter in the range of Å is 0.3 to 0.
It is in the range of 9 ml / g, preferably 0.3 to 0.6 ml / g. The catalyst of the present invention has the following characteristics in addition to the above properties. (7) The volume F of pores having a diameter in the range of 150 to 2000 Å measured by the mercury penetration method is 0.3 to 0.9 m.
It is in the range of 1 / g, preferably 0.3-0.6 ml / g. (8) The volume G of pores having a diameter in the range of 150 to 300Å measured by the nitrogen adsorption method is 10 to 30% of the volume B of pores having a diameter in the range of 0 to 300Å, preferably 15 to 20. It is in the range of%. (9) The volume H of pores having a diameter in the range of 0 to 600Å measured by the nitrogen adsorption method is 0.8 to 1.2 ml / g.
Is in the range.

If necessary, other metal components such as magnesia, calcium oxide, zirconia, boria, hafnia, and crystalline zeolite can be added to the silica-alumina of the present invention. These metal components can be added by a mixing method, or can be added by a conventionally known impregnation method or a coprecipitation method, but it is preferable to add them by an impregnation method. When adding by the impregnation method,
Silica-alumina is immersed in an impregnation solution containing a predetermined soluble metal component to impregnate silica-alumina with a desired amount of the metal component, and then dried and fired. The hydrotreating catalyst of the present invention can be obtained by supporting a hydrogenation active metal on the silica-alumina. As a method for supporting the hydrogenation active metal, a conventionally known impregnation method or a coprecipitation method can be used, but the impregnation method is preferable. The pore characteristics of the hydrotreating catalyst of the present invention correspond to those of silica-alumina used as a carrier thereof, and the catalyst of the present invention has pore characteristics almost equivalent to those of silica-alumina used as a carrier.

Hydrogenation active metal components supported on silica-alumina include metals of Group VIB and V of the Periodic Table of Elements.
One or more metals selected from the group III group metals are selected. That is, one or more selected from the group VIB chromium, molybdenum and tungsten, the group VIII iron, cobalt, nickel, palladium, platinum, osmium, iridium, ruthenium and rhodium are used. For hydrodesulfurization of hydrocarbon oils, in particular:
Combinations of Group VIB and Group VIII metals, such as molybdenum-cobalt, molybdenum-nickel, tungsten-nickel, molybdenum-cobalt-nickel or tungsten-cobalt-nickel, can be preferably used. It is also possible to add and use a metal of Group VII, for example, manganese, and a metal of Group IV, for example, tin, germanium, etc., to these active metal components. These hydrogenation active metal components are preferably supported as oxides and / or sulfides. In addition, titania or the like can be simultaneously loaded on the carrier in order to enhance the catalyst strength. The amount of the metal component supported may be, as an oxide, about 0.5 to 20% by weight of the Group VIII metal in the catalyst and about 5 to 30% by weight of the Group VIB metal. Further, the metal component added for improving the catalyst strength is 0.5 to 1.5% by weight, preferably 0.9 to 1.1% by weight in the catalyst.

When the supported metal is supported on silica-alumina by the impregnation method, either one-liquid impregnation method or two-liquid impregnation method may be adopted depending on the kind of the metal to be supported. That is, in order to support two or more metal components, two or more metal components are mixed and impregnated simultaneously from the mixed solution (one-liquid impregnation method), or two or more metal component solutions are separately prepared. Prepare and sequentially impregnate (two-component impregnation method)
However, the metal supporting method is not particularly limited in the present invention.

In order to preferably produce the catalyst of the present invention, the above-mentioned silica-alumina is used as a carrier, and one of the metals selected from the group of Group VIII metals of the Periodic Table of Elements is first used on this carrier. Support two or more metals
(First step), and then one or more metals selected from the group of Group VIB metals of the Periodic Table of the Elements are supported (second step). More specifically, according to this two-step method, the hydrogenation-active metal component supported on the carrier in the first step is one or more metals selected from Group VIII metals of the Periodic Table of the Elements. Is. That is, VIII
One or more selected from the group consisting of iron, cobalt, nickel, palladium, platinum, osmium, iridium, ruthenium and rhodium are used. Preferably, cobalt and nickel are used alone or in combination of both. The hydrogenation-active metal component supported on the carrier in the second step is one or more metals selected from the group of Group VIB metals of the Periodic Table of the Elements. That is, one or more selected from the VIB group chromium, molybdenum, and tungsten are used. Preferably molybdenum and tungsten are used alone or in combination.

It is preferable that the hydrogenation-active metal components of Group VIII and Group VIB are supported as oxides and / or sulfides. In the two-step supporting method according to the first and second steps, The supported amount of the metal component is 0.1 to 20% by weight, preferably 1 to 8% by weight, and more preferably 2 to 5% by weight in the catalyst, based on the oxide. For Group VIB metals 3 to 30% by weight, preferably 8
-25% by weight, more preferably 5-20% by weight.
If less than 0.1% by weight of the Group VIII metal is supported, a catalyst having sufficient activity cannot be obtained, and if it exceeds 20% by weight, the amount of free metal components not bound to the carrier increases. VI
An increase in the free components of Group II metals results in the formation of inert complex oxides when supporting Group VIB metals,
It lowers the dispersibility of Group VIB metals and lowers the catalytic activity. On the other hand, if the amount of the Group VIB metal is less than 3% by weight, the activity cannot be obtained, and if the amount of the Group VIB metal is more than 10% by weight, the dispersibility is lowered and the cocatalyst effect of the Group VIII metal is not exhibited.

In the method for supporting the catalytic metal, the method of supporting the active metal component on the carrier in the first and second steps is as follows: the carrier is immersed in an aqueous solution of a soluble salt of the metal, and the metal component is introduced into the carrier. An impregnation method can be adopted. As the impregnation operation, the carrier is immersed in the impregnating solution at room temperature or above room temperature to maintain the condition that the desired component is sufficiently impregnated into the carrier. The amount and temperature of the impregnating solution can be appropriately adjusted so that a desired amount of metal is supported. The amount of carrier to be dipped in the impregnation solution is determined according to the supported amount. The catalyst of the present invention may have any shape such as a cylindrical shape, a granular shape or a tablet shape, and such a shape is determined according to a molding method such as extrusion molding or granulation molding. The diameter of the molded product is preferably in the range of 0.5 to 3.0 mm. The carrier impregnated with the hydrogenation active metal component is washed with water after separating the impregnation solution.
Dry and bake. The conditions of drying and baking may be the same as the conditions for the above carrier. In hydrodesulfurization of heavy hydrocarbon oils, the catalyst is preferably subjected to pre-sulfurization prior to use. The method will be described later.

The catalyst produced as described above is a catalyst in which at least one hydrogenation active metal component is supported on a silica-alumina carrier containing about 10 to 20% by weight of silica. It is characterized by having a catalytic property. (1) 250 m ² / g or more, especially 255 to 350 m ² / g
Has a total surface area of. (2) Pore diameter of 30 to 30 measured by nitrogen adsorption method
It has the first peak of the pore volume distribution in the range of 0Å. (3) Pore diameter measured by mercury porosimetry is 300 to 1
It has a second peak of the pore volume distribution in the range of 500Å. (4) The volume A of pores having a diameter of 30 to 300Å including the first peak is 80% or more of the volume B of pores having a diameter of 0 to 300Å measured by a nitrogen adsorption method, and particularly,
It is in the range of 80 to 95%. (5) The volume C of pores having a diameter in the range of 300 to 1500Å including the second peak is 15 to 40%, preferably 15 to 40% of the volume D of pores having a diameter of 0 to 1500Å.
It is in the range of 30%. (6) 150-150,000 measured by mercury porosimetry
The volume E of pores having a diameter in the range of Å is 0.3 to 0.
It is in the range of 9 ml / g, preferably 0.3 to 0.6 ml / g. The catalyst of the present invention has the following characteristics in addition to the above properties. (7) The volume F of pores having a diameter in the range of 150 to 2000 Å measured by the mercury penetration method is 0.3 to 0.9 m.
It is in the range of 1 / g, preferably 0.3-0.6 ml / g. (8) The volume G of pores having a diameter in the range of 150 to 300Å measured by the nitrogen adsorption method is 15 to 30%, preferably 15 to 20% of the volume B of pores having a diameter in the range of 0 to 300Å. It is in the range of%. (9) The volume H of pores having a diameter in the range of 0 to 600Å measured by the nitrogen adsorption method is 0.8 to 1.2 ml / g.
Is in the range.

The nitrogen adsorption method and mercury porosimetry used as a method for measuring the pore volume of silica-alumina and catalysts are described in P.
H. Emmet et al., "Catalysis," Vol. 1, p. 123 (Published by Linehold Publishing Company) (1
959) PH Emmett, et al. “Catalysis”, 1,123 (1959)
(Reinhold Publishing Co.), and Catalysis Engineering Course, 4th
Volume, pp. 69-78 (published by Jishin Shokan) (Showa 39)
Year). In the mercury porosimetry, the contact angle of mercury with the catalyst was 130 °, the surface tension was 485 dynes / cm, and it was assumed that all pores were cylindrical. Various correction methods based on multi-layer adsorption have been proposed for the nitrogen adsorption method. Among them, the BJH method [EP
Barreff. LG Joyner and PPHalnda, J._Amer., Ch
em, Sco., 73 , 373 (1951)] and CI method [RW Cranston
and FA Inkley, “Advances in Catalysis,” 1X , 143
(1957) (New York Academic Press)] is generally used. The data relating to the pore volume in the present invention uses the adsorption side of the adsorption isotherm and the DH method [D.Dollimore and GR
Heal, J. Appl., Chem., 14 , 109 (1964)].

Next, hydrorefining of hydrocarbon oil by using the catalyst of the present invention will be described. As a hydrocarbon oil,
Straight-run light oil, cracked light oil, vacuum distilled light oil, heavy cracked oil and the like can be used. The vacuum-distilled gas oil is a distillate oil containing a fraction having a boiling point in the range of about 370 ° C. to 610 ° C., which is obtained by distilling an atmospheric distillation residue oil under reduced pressure, and corresponds to a sulfur content, a nitrogen content and a metal content. It is contained in an amount. For example,
Middle East crude oil If you give an example of vacuum distillation gas oil, it is about 2-4
It contains sulfur by weight and about 0.05-0.2% nitrogen by weight. Heavy cracked oil is cracked oil having a boiling point of about 200 ° C. or higher obtained by thermally cracking residual oil, and for example,
Light cycle oil from a catalytic cracker, light oil obtained from coking of residual oil and visbreaking, etc. can be used. Further, as hydrocarbon oil, sulfur content,
Contains nitrogen, asphalt and metal-containing compounds,
A substance having a boiling point of substantially 480 ° C. or higher can be used. Such a hydrocarbon oil contains crude oil at atmospheric pressure or vacuum distillation residue oil. For example, about 4 at normal pressure
About 30 to 10 hydrocarbon components having a boiling point of 80 ° C or higher
Residual oils in the range of 0% by weight typically contain about 1-10% by weight sulfur, about 0.1-1% by weight nitrogen, about 10-100%.
It contains 0 ppm of metal and about 1% by weight of residual carbon (Conradson). As described above, as the feedstock oil, it is possible to use the atmospheric distillation residue oil, the vacuum distillation residue oil, the vacuum distillation gas oil, the heavy cracked oil, the atmospheric distillation gas oil, the cracked gas oil or a mixed oil thereof as described above. it can.

The reaction conditions can be appropriately selected according to the type of feed oil, the desired desulfurization rate or denitrification rate. That is, reaction temperature: about 320 to 420 ° C., reaction pressure: about 30 to 200 kg / cm ² , ratio of hydrogen-containing gas to feedstock oil: about 100 to 270 liters / liter, and liquid space velocity: about 0.2 to 2 Adopt 0.0V / H / V. The hydrogen concentration in the hydrogen containing gas may range from about 60-100%. In carrying out the hydrodesulfurization, the catalyst may be used in any form of a fixed bed, a fluidized bed or a moving bed, but it is preferable to adopt the fixed bed in terms of equipment or operation. It is also possible to combine two or more reaction towers for hydrodesulfurization to achieve a high desulfurization rate. Further, since the catalyst of the present invention is rich in macropores, it can be used as a demetallizing catalyst in a card drum for metal removal attached to a main reaction column mainly for desulfurization and denitrification.

The catalyst of the present invention is preferably presulfidized prior to use. Presulfiding can be carried out in situ in the reaction tower. That is, the calcined catalyst was mixed with sulfur-containing distillate oil, temperature: about 150 to 400 ° C., pressure (total pressure): about 20 to 100 kg / cm ² , liquid space velocity: about 0.3 to 2.0 V / H / After contacting in the presence of V and about 50-1500 liters / liter of hydrogen-containing gas, after completion of the sulfurization treatment, the sulfur-containing distillate oil is switched to the feedstock and the operation is started by setting appropriate operating conditions for desulfurization of the feedstock. To do.
In addition to the above methods, the sulfurization treatment may be carried out by directly contacting the catalyst with hydrogen sulfide or other sulfur compound, or by adding it to a suitable distillate oil and contacting it with the catalyst.

[0022]

The catalyst of the present invention has the following catalytic properties.
The catalyst of the present invention is characterized by having the above-mentioned pore characteristics, and the greatest feature of the catalyst of the present invention is that the first peak of the pore volume distribution is in the range of 30 to 200Å and the pore diameter is 300 to
It has a second peak of pore volume in the range of 1500Å. The catalyst of the present invention and the above-mentioned known catalyst (Japanese Patent Publication No.
No. 31496), the known catalyst has no second peak, whereas the catalyst of the present invention has a second peak, and the pore diameter is 1
The pore volume in the range of 50 to 150000Å is as low as 0.01 to 0.03 ml / g in the known catalyst, while the catalyst of the present invention has a high value of 0.3 ml / g or more. The catalyst of the present invention has the above-mentioned difference in properties as compared with the above-mentioned known catalyst, and as a result, has the following advantages in its catalytic performance. (1) Uniform dispersibility of the supported hydrogenation active metal is high.
The reason for this is that the silica-alumina used as a carrier in the present invention has a large specific surface area and is excellent in metal-supporting property. When the catalyst of the present invention was analyzed by X-ray diffraction, crystals of the supported catalyst metal component were not confirmed, and it was judged that the catalyst metal component was uniformly dispersed in the silica-alumina surface in an amorphous state. It (2) Since the average pore diameter is large, clogging of the pore inlet due to coke hardly occurs, and the catalyst activity maintaining ability is excellent. (3) A non-desulfurizing sulfur-containing sulfur having a large amount of acid and a high acid strength as compared with a carrier made of alumina alone, having a hydrocracking function and having a structure that causes steric hindrance to the hydrogenation reaction. The compounds can also be easily desulfurized.

The silica-alumina of the present invention has a structure in which silica is layered on the surface of which alumina is a core and has pore characteristics equivalent to those of the catalyst described above. This is preferably used as a carrier for hydrodesulfurization catalyst,
Similar to conventional silica-alumina, catalyst carrier, adsorbent,
Used as a filler, etc.

[0024]

EXAMPLES Next, examples of the present invention will be described. Example 1 1.0 liter of pure water was heated to about 70 ° C., and an aqueous sodium hydroxide solution (169 g of NaOH, 420 g of pure water) was added thereto.
Was added to make alkaline water having a pH of about 12. Then, after adding an aluminum sulfate aqueous solution (466 g of aluminum sulfate and 710 g of pure water) to the alkaline water within 5 seconds,
Adjust the pH to 8.8 with sodium hydroxide solution or nitric acid solution.
It was adjusted to 9.2 and aged at about 70 ° C. for about 1 hour. As a result, an aqueous solution containing a precipitate (gel) of alumina hydrate was obtained. An aqueous sodium silicate solution (69 g of No. 3 water glass, 210 g of pure water) was added to this aqueous solution, and a nitric acid solution was added as necessary to adjust the pH to about 9, and the mixture was aged at a temperature of about 70 ° C. for 3 hours. As a result, a slurry liquid containing precipitated particles in which silica hydrate was deposited on the surface of alumina hydrate was obtained.
The slurry solution was filtered, and the filtered cake was washed with an aqueous ammonium carbonate solution until the sodium concentration of the filtrate after filtration was 5 ppm or less. 80 this cake
The mixture was kneaded while being dried in a kneader at 0 ° C. until it had a water content capable of molding, and was molded into a cylindrical pellet of 1.5 mmφ by an extrusion molding machine. The molded pellets are 120
It was dried at 16 ° C. for 16 hours and then calcined at 600 ° C. for 3 hours to obtain a carrier. Then, about 2 as an oxide is added to this carrier.
An aqueous solution of ammonium paramolybdate (molybdenum solution) was impregnated so that 0 wt% of molybdenum was supported, dried, and baked at 550 ° C. Next, an aqueous solution of cobalt nitrate (cobalt solution) is impregnated so that about 5 wt% of cobalt is supported as an oxide, and dried at 450 ° C.
It was then calcined to obtain a catalyst.

Example 2 The pelletized carrier obtained in Example 1 was impregnated with an aqueous solution of molybdenum so that about 17 wt% of molybdenum was supported as an oxide, dried and calcined at 550 ° C. did. Next, a cobalt solution was impregnated so that about 3.7 wt% of cobalt was supported as an oxide, dried, and calcined at a temperature of 450 ° C. to obtain a catalyst.

Example 3 The pelletized carrier obtained in Example 1 was impregnated with a molybdenum solution so that about 20 wt% of molybdenum as an oxide was supported, dried and calcined at 550 ° C. Next, a cobalt solution is impregnated and dried so that about 3.5 wt% of cobalt is supported as an oxide, and the temperature is 450 ° C.
It was then calcined to obtain a catalyst.

The properties of each catalyst obtained as described above are shown in Table 1 together with the comparative catalyst. The symbols shown in Table 1 indicate the following contents. A: Pore volume having a pore diameter in the range of 30 to 300Å B: Pore volume having a pore diameter in the range of 0 to 300Å C: Pore volume having a pore diameter in the range of 300 to 1500Å D: Pore volume with pore diameter in the range of 0 to 1500Å G: Pore volume with pore diameter in the range of 150 to 300Å Further, Comparative catalyst A shown in Table 1 is a commercially available desulfurization catalyst, and comparative catalyst B is a catalyst obtained according to the description in Japanese Examined Patent Publication No. 3-31496.

The catalyst of Example 1 and the comparative catalysts A and B were analyzed by an X-ray diffractometer (XRD). As a result, no crystalline CoMoO ₄ (cobalt molybdate) was detected in the catalyst of Example 1. In comparative catalysts A and B, peaks of fine crystals of metal oxide were detected. This shows that the catalyst of the present invention has excellent dispersibility of Mo and Co.

[0029]

[Table 1]

Application Example 1 Using the catalyst of Example 1 and comparative catalysts A and B, the hydrodesulfurization treatment of the cracked gas oil fraction obtained from the catalytic cracking apparatus was carried out. Table 2 shows the hydrodesulfurization conditions.

[0031]

[Table 2] Table 3 shows the results of the hydrodesulfurization treatment. The sulfur level of the hydrotreated product oil is 0.04 to 0.07 wt%.

[0032]

[Table 3]

Application Example 2 Using Example 1 and Comparative Catalysts A and B, hydrodesulfurization treatment of straight-run light oil fraction was performed. The sulfur level of the hydrotreated product is 0.01 to 0.04 wt%. Table 4 shows the hydrodesulfurization conditions.

[0034]

[Table 4] Table 5 shows the results of the hydrodesulfurization treatment. The sulfur level of the hydrotreated product oil is 0.04 to 0.07 wt%.

[0035]

[Table 5]

Comparative Example 1 An experiment was conducted in the same manner as in Example 1 except that the time for adding the aluminum sulfate aqueous solution to the alkaline water was 70 minutes. The silica-alumina obtained in this case had a specific surface area of 18 as a carrier for hydrotreating catalyst.
It was as low as 3 m ² / g and was unsatisfactory.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number in the agency FI Technical indication C10G 45/04 A 2115-4H 45/12 A 2115-4H (72) Inventor Kazuo Saeki Iruma, Saitama Prefecture 1-3-1 Nishitsurugaoka, Oi-machi, Tonen Research Institute, Tonen Corporation (72) Inventor Tomio Ueda 1-3-1 Nishi-Tsurugaoka, Oi-cho, Iruma-gun, Saitama Tonen Research Institute (72) Inventor Hayashi Ikutaka 1-3-3 Nishitsurugaoka, Oi-cho, Iruma-gun, Saitama Prefecture Tonen Corporation Research Institute

Claims (3)

[Claims] 1. A silica-alumina having a structure in which a silica layer is formed on the surface of alumina as a core and containing 10 to 20% by weight of silica, wherein the pore diameter measured by a nitrogen adsorption method is 30. The first peak of the pore volume distribution in the range of ~ 300 Å, the pore diameter measured by mercury porosimetry is 3
The volume A of the pores having the second peak of the pore volume distribution in the range of 00 to 1500 Å and having the diameter in the range of 30 to 300 Å including the first peak is in the range of 0 to 300 Å measured by the nitrogen adsorption method. The volume B of the pores having a diameter is 80% or more and 300 to 150 including the second peak.
Volume C of pores having a diameter in the range of 0Å is 0 to 1500
150 to 15000, which is in the range of 15 to 40% of the pore volume D having a diameter of Å and measured by the mercury porosimetry.
The volume E of pores having a diameter in the range of 0Å has a value of 0.3 to 0.
It is in the range of 9 ml / g and the total surface area is 250 m ^2.
/ G or more, silica-alumina characterized by the above-mentioned. 2. A silica-alumina-containing carrier having a structure in which a silica layer is formed on the surface of alumina as a core and containing 10 to 20% by weight of silica, and at least one hydrogenation-active metal component is supported on the carrier. The catalyst has a first peak of pore volume distribution in the range of 30 to 300Å as measured by nitrogen adsorption method, and a pore diameter in the range of 300 to 1500Å as measured by mercury porosimetry. 30 to 3 including the first peak while having the second peak of the volume distribution
The volume A of the pores having a diameter in the range of 00Å is 80% or more of the volume B of the pores having a diameter in the range of 0 to 300Å measured by the nitrogen adsorption method, and includes the second peak.
The volume C of pores having a diameter in the range of 0 to 1500Å is 0
15-40% of the pore volume D having a diameter of ~ 1500Å
Range of 150 and measured by mercury porosimetry
A hydrotreating catalyst characterized in that the volume E of pores having a diameter in the range of 150,000 Å is in the range of 0.3 to 0.9 ml / g and the total surface area is 250 m ² / g or more. 3. The method for producing silica-alumina according to claim 1, wherein an acidic aluminum aqueous solution is added to and mixed with an aqueous sodium hydroxide solution having a pH range of 7 to 13 within 45 seconds, and the mixed solution is heated to 60 to 80 ° C. A step of holding and precipitating alumina hydrate, an aqueous solution of the water-soluble silicon compound is added to and mixed with an aqueous solution containing the precipitate of alumina hydrate, and the temperature is kept at 60 to 80 ° C. under the condition of pH 7 to 10. And a step of depositing a silica hydrate on the alumina hydrate precipitate.