JP4818156B2 - Hydrocarbon oil catalytic cracking catalyst and method for catalytic cracking of hydrocarbon oil using the catalyst - Google Patents

Description

  The present invention relates to a catalytic cracking catalyst for hydrocarbon oil (hereinafter sometimes referred to as "FCC catalyst") and a method for catalytic cracking of hydrocarbon oil using the same, more specifically, having a high cracking activity, Hydrocarbons that can reduce the production of cracked products such as dry gas (hydrogen, C1-C2), LPG, and coke, and improve the yield of gasoline fractions (hereinafter sometimes referred to as “FCC gasoline”). The present invention relates to an oil catalytic cracking catalyst and a hydrocarbon oil catalytic cracking method using the catalyst.

  Catalytic cracking of heavy hydrocarbon oil is a reaction that converts low-grade heavy oil obtained in the petroleum refining process into light hydrocarbon oil by catalytic cracking. When producing FCC gasoline, As by-products, dry gas (hydrogen, C1 to C2), coke, liquefied petroleum gas (Liquid Petroleum Gas: LPG), middle distillate (Light Cycle Oil: LCO), heavy distillate (Heavy Cycle Oil: HCO) ) Is produced. In order to efficiently produce FCC gasoline, it is desirable that the catalytic cracking activity is high, the gasoline yield is high, and the selectivity of dry gas, LPG, coke and heavy fraction is low.

  In addition, gasoline for automobiles is manufactured by mixing a plurality of gasoline base materials obtained in the refining process of crude oil. FCC gasoline obtained from catalytic cracking of heavy hydrocarbon oils is blended with gasoline. Because of the large amount, it is desirable for those skilled in the art to improve FCC gasoline yield.

  However, in the catalytic cracking method for hydrocarbon oils, with the recent increase in crude oil grades and grades, heavy metals such as vanadium and nickel and feedstocks with high residual carbon content must be put into the fluid catalytic cracking unit. There is a situation that cannot be avoided. When vanadium is deposited and deposited on the FCC catalyst, it destroys the structure of the crystalline aluminosilicate that is the active component of the FCC catalyst, causing a significant decrease in the activity of the catalyst and increasing the production of hydrogen and coke. It is known to have problems such as lowering the selectivity. Nickel is also deposited on the surface of the catalyst and has problems such as increasing the amount of hydrogen and coke generated in order to promote the dehydrogenation reaction and reducing the selectivity of the gasoline fraction.

Conventionally, a catalytic cracking catalyst composed of an inorganic oxide matrix such as zeolite or clay mineral and a binder is often used for catalytic cracking of hydrocarbon oil (see, for example, Patent Documents 1 to 3). However, with conventional catalytic cracking catalysts, as described above, with the recent increase in crude oil weight and quality, there is an increase in the production of dry gas, LPG and coke, and a decrease in the selectivity of gasoline fractions. There is a problem, and there is a strong demand for reduction in the amount of dry gas, LPG, and coke produced from the catalytic cracking catalyst, and improvement in the selectivity of gasoline fractions.
JP-A-8-57328 JP-A-9-285728 Japanese Patent Laid-Open No. 10-118501

  In view of the above circumstances, in the catalytic cracking of hydrocarbon oil, the present invention improves the decomposability of heavy fractions and at the same time reduces the amount of cracked products such as dry gas, LPG and coke, and An object of the present invention is to provide a catalytic cracking catalyst capable of improving the selectivity of gasoline fraction and producing FCC gasoline efficiently and in high yield.

  As a result of repeated studies to achieve the above-described object, the present inventors have determined that a crystal particle has a specific crystal structure and a specific number of layers in image measurement using a scanning electron microscope (SEM). FCC catalyst using clay minerals that have high cracking activity in catalytic cracking reaction of hydrocarbon oil, reduce the production of dry gas, LPG, coke and improve the selectivity of gasoline fraction The present inventors have found that FCC gasoline can be produced efficiently and with high yield, and have completed the present invention.

That is, this invention provides the following catalytic cracking catalyst of hydrocarbon oil, and the catalytic cracking method of hydrocarbon oil using the same.
(1) In image measurement using a scanning electron microscope, 10 to 75% by mass of a clay mineral having a plate-like crystal structure and an average number of stacked layers of 15 to 50 %, crystalline aluminosilicate A catalytic cracking catalyst for hydrocarbon oil, comprising 20 to 50% by mass of a salt and 5 to 40% by mass of a silica binder as a binder.
(2) A method for catalytic cracking of hydrocarbon oil, wherein the catalytic cracking catalyst for hydrocarbon oil described in (1) above is used for catalytic cracking of hydrocarbon oil.

  The catalytic cracking catalyst according to the present invention has high cracking activity in catalytic cracking of hydrocarbon oil, reduces the amount of dry gas, LPG and coke produced, and improves the selectivity of gasoline fractions. Gasoline can be obtained efficiently and in high yield. In general, in the FCC process, the cost and burden on the FCC apparatus can be reduced if the amount of dry gas, LPG, and coke produced can be reduced even slightly. In particular, when the FCC apparatus is operated at a high operating rate, by reducing the dry gas, LPG, and coke, the regeneration tower temperature and the gas section can be afforded, so that the apparatus can be operated more efficiently. Further, since FCC gasoline generally has a large blending amount with gasoline to be shipped to the market, the profit generated by improving the selectivity of gasoline is very large.

  That is, the FCC catalyst of the present invention has a high cracking activity as described above, reduces the generation amount of dry gas, LPG and coke, and improves the selectivity of the gasoline fraction, so that FCC gasoline can be efficiently used. Since it can be obtained in a high yield, it is extremely effective in practice.

Hereinafter, embodiments of the present invention will be described in detail.
<Components of catalyst>
The catalytic cracking catalyst according to the present invention comprises a crystalline aluminosilicate, a clay mineral, and a silica binder.

(Crystalline aluminosilicate)
The crystalline aluminosilicate used for the catalyst component in the present invention may be a natural product or an artificial product, and its structural form is wide-ranging, and is tetragonal, orthorhombic, cubic. Have a hexagonal crystal structure. As this crystalline aluminosilicate, mordenite, β zeolite, ZSM zeolite, A-type zeolite, X-type zeolite, Y-type zeolite and the like can be used, Y-type zeolite is preferable, and stabilized Y-type zeolite is particularly preferable. . As the stabilized Y-type zeolite, (a) bulk SiO ₂ / Al ₂ O ₃ molar ratio by chemical composition analysis is 4 to 15, preferably 5 to 10, and (b) unit cell size is 24.35 to 24. 65 cm, preferably 24.40 to 24.60, (c) The molar ratio of Al in the zeolite framework to the total Al is 0.3 to 1.0, preferably 0.4 to 1.0. Can do. This stabilized Y-type zeolite has basically the same crystal structure as natural faujasite and has the following composition as an oxide.
_{(0.02~1.0) R 2 / mO ·} Al 2 O 3 · (5~11) SiO 2 · (5~8) H 2 O
R: Na, K, other alkali metal ions, alkaline earth metal ions m: R valence

The unit cell size of the zeolite used in the present invention can be measured by an X-ray diffractometer (XRD), and the number of moles of Al in the zeolite framework relative to the total Al is determined by SiO ₂ / Al ₂ O ₃ by chemical composition analysis. It can be calculated from the ratio and unit cell size using the following formulas (A) to (C). In addition, Formula (A) is H.264. K. Beyeretal. , J .; Chem. Soc. , Faraday Trans. 1, (81), 2899 (1985). Is adopted.
N _A1 = (a _o -2.425) /0.000868 (A)
a _o : unit cell size / nm
N _Al : Number of Al atoms per unit cell 2.425: Unit cell size when all Al atoms in the unit cell skeleton are desorbed outside the skeleton 0.000868: Calculated value obtained by experiment, a _o and Inclination of N _Al when arranged by a linear expression (a _o = 0.000868N _Al +2.425) (Si / Al) calculation formula = (192−N _Al ) / N _Al (B)
192: Number of atoms of (Si + Al) per unit cell dimension of Y-type zeolite-Al in zeolite framework / total Al = (Si / Al) chemical composition analysis value / (Si / Al) calculation formula (C )

The SiO ₂ / Al ₂ O ₃ molar ratio of the zeolite indicates the acid strength of the catalyst. Generally, the larger the molar ratio, the stronger the acid strength of the catalyst. In general, when the SiO ₂ / Al ₂ O ₃ molar ratio is 4 or more, the acid strength necessary for the catalytic cracking of heavy hydrocarbon oil can be obtained, and as a result, the cracking reaction proceeds suitably. preferable. Moreover, it is preferable that it is 15 or less because the number of required acids decreases and it can suppress that the decomposition activity of heavy hydrocarbon oil falls.

  The unit cell size of the zeolite indicates the size of the unit unit constituting the zeolite. However, when the unit cell size is 24.35 mm or more, the number of Al necessary for the decomposition of the heavy hydrocarbon oil is excessively reduced, and as a result It is preferable because decomposition can be prevented from being difficult to proceed. Moreover, it is preferable that it is 24.65 or less because deterioration of a zeolite crystal | crystallization progresses easily and it can suppress that the fall of the decomposition activity of a FCC catalyst becomes remarkable.

If the molar ratio of Al in the zeolite framework to the total Al is 0.3 or more, the amount of Al constituting the zeolite crystal becomes too small, and as a result, more Al ₂ O ₃ particles fall off from the zeolite framework. Since the strong acid point is not expressed, it is preferable to prevent the catalytic decomposition reaction from proceeding. Moreover, when the molar ratio of Al in the zeolite framework to the total Al is close to 1, it means that most of the Al in the zeolite is taken into the zeolite unit cell, and the Al in the zeolite is effective for the expression of strong acid sites. It is preferable because it contributes to

As a zeolite that satisfies the above requirements, the heat shock crystalline silicate described in Japanese Patent No. 2544317 can also be used. This zeolite has a SiO ₂ / Al ₂ O ₃ molar ratio of 5 to 15, a unit cell size of 24.50 or more and less than 24.70, and an alkali metal content of 0.02% by mass or more and less than 1% by mass in terms of oxides. The stabilized Y-type zeolite is calcined at 600 to 1200 ° C. for 5 to 300 minutes in air or nitrogen atmosphere so that the crystallinity reduction rate is 20% or less. SiO ₂ / Al ₂ O ₃ molar ratio is 5 to 15, molar ratio of Al in zeolite framework to total Al is 0.3 to 0.6, unit cell size is less than 24.45 mm, alkali metal content is oxide equivalent 0.02% by mass or more and less than 1% by mass, showing a characteristic peak in the pore distribution around 50 and 180%, with a pore volume of 100 or more being 10 to 40% of the total pore volume, and Y Type Z It is a crystalline aluminosilicate with the main X-ray diffraction pattern of Olite.

(Silica binder)
The silica binder used as a catalyst component in the present invention exists between particles such as crystalline aluminosilicate and clay mineral, improves the moldability when the catalyst is made fine, makes the catalyst fine particles spherical, and is also obtained. Used as a binder to improve the fluidity and wear resistance of the catalyst fine particles. Since the silica binder does not exhibit solid acid properties, it does not have decomposition activity by itself, but contributes to the formation of mesopores and can reduce the amount of coke produced.

  Several types of silica binders are known. Examples of colloidal silica include sodium sol, lithium type, and acid type silica sols. Any of these types can be used in the present invention. Considering production of a catalytic cracking catalyst on a commercial scale, silica hydrosol obtained by reacting a low-cost diluted water glass aqueous solution with a sulfuric acid aqueous solution can be preferably used. Moreover, an alumina binder etc. can also be mixed and used unless it deviates from the effect acquired by this invention.

(Clay mineral)
The clay mineral used in the present invention has a property in which the crystal particles have a plate-like crystal structure and the average number of layers exceeds 10 in image measurement using a scanning electron microscope (SEM). Any number of layers may be mixed. In addition, a plate crystal having an average number of layers exceeding 10 is preferable because it has good decomposability into the catalyst particles, but a sample having an average number of layers exceeding 100 has poor dispersibility in the catalyst particles. Therefore, the average number of plate crystals is preferably more than 10 and 100 or less, more preferably 15-50. A catalyst using a plate crystal having an average number of laminated layers of 15 to 250 has a higher cracking activity in catalytic cracking of hydrocarbon oil, and reduces the amount of dry gas, LPG and coke produced, In addition, the selectivity of the gasoline fraction can be improved, and an excellent effect that FCC gasoline can be produced efficiently and in high yield can be obtained.

  Here, the average number of laminated clay minerals is defined by the following method. That is, dozens of images at different locations are photographed with a scanning electron microscope (SEM) at a photographing magnification of 5000 times or more (a magnification at which the number of layers can be analyzed). The number of layers for a total of 100 particles in each image is calculated to determine the average number of layers.

  There are various types of clay minerals such as montmorillonite, kaolin, bentonite, attapulgite, bauxite, quartz (quartz), illite, boehmite, etc. In the present invention, in the image measurement using the scanning electron microscope (SEM) as the clay mineral. As long as it is confirmed that the crystal particles have a plate-like crystal structure and the average number of laminated layers exceeds 10, any one of various clay minerals may be used alone. It is also possible to use a mixture of seeds. Further, it may be a natural product or a synthetic product. Of these, kaolin or those containing kaolin as a main component is preferably used. In the present invention, if necessary, a clay mineral having the above-mentioned certain crystal structure and a clay mineral not having the above-mentioned crystal structure may be mixed and used as long as the desired effect of the present invention can be obtained. it can.

The kaolinite includes kaolinite (hexagonal plate shape, kaolinite-1A), kaolinite with disordered stacking (hexagonal plate shape, kaolinite-1Md), halloysite (needle shape), nacrite (hexagonal plate shape, kaolinite-1M). Dickite (plate shape, kaolinite-2M) is known, but the kaolin mineral used in the present invention is a plate shape such as a hexagonal plate shape or other shape plate shape. . A hexagonal plate-shaped crystal structure is preferable because the particle shape can be easily adjusted and catalyst particles having higher strength and wear resistance can be granulated. Furthermore, the one showing the XRD pattern of kaolinite-1Md (representative peak: 2θ = about 12, 20, 25 °) can granulate catalyst particles having further excellent strength and wear resistance, In catalytic cracking, it has high cracking activity, reduces the amount of dry gas, LPG and coke produced, and improves the selectivity of gasoline fraction, making it possible to produce FCC gasoline efficiently and in high yield. An effect can be acquired and it is the most preferable. Here, the symbols “1A” and “1Md” indicate the polytype (polymorphism) of the crystal, A indicates triclinic, M indicates monoclinic, and The number before the symbol indicates the number of unit structural layers included in the unit cell.
The kaolin mineral is represented by the composition formula shown below.
_{Al 2 SiO 5 (OH) 4} (Al 2 SiO 5 when with water molecules between the layers _{(OH) 4 · 2H 2 O} )

Further, the particle diameter of the clay mineral used in the present invention is not particularly limited as long as it is equal to or smaller than the particle diameter of the catalyst, but the average particle diameter is 0.1 to 10 μm. It is preferable because it can be granulated. Moreover, the clay mineral used in the present _invention, SiO 2 / _Al 2 _{O 3} molar ratio 1.0 to 2.5, water content 2.0% by mass or less, oil absorption of 40~80 (cc / 100g), the surface area 5~40m It is preferable to have a property of ² / g because the raw material hydrocarbon oil can be efficiently absorbed and decomposed.

In the catalyst of the present invention, by containing a clay mineral having the above-mentioned constant crystal shape and average number of layers, the catalyst has high cracking activity in the catalytic cracking of hydrocarbon oil and produces dry gas, LPG and coke. By reducing the amount and improving the selectivity of the gasoline fraction, it is possible to obtain an excellent effect that FCC gasoline can be produced efficiently and in high yield.
Although the details of the reason why such excellent effects can be obtained with the catalyst of the present invention are not necessarily clear, it is suitable for catalytic cracking reaction by containing the clay mineral having the above-mentioned constant crystal structure and properties of average number of layers. This is probably because the pore characteristics were formed. That is, in the catalytic cracking catalyst of the present invention, the contact efficiency between the raw hydrocarbon oil and the cracking active point is improved, so that the production amount of dry gas, LPG and coke is reduced, and the selectivity of the gasoline fraction is improved. It is thought that the effect is obtained.

(Other ingredients)
In the catalyst of the present invention, as other components, ordinary catalytic cracking such as silica, silica-alumina, alumina, pseudoboehmite, silica-magnesia, alumina-magnesia, phosphorus-alumina, silica-zirconia, silica-magnesia-alumina, etc. It is also possible to contain oxide fine particles of a known inorganic oxide used for a catalyst for a catalyst. These also function as a matrix component of the catalyst in the same manner as the clay mineral. In addition, an alkaline earth or an inorganic oxide having a metal inactivating function such as manganese, antimony, tin, or the like can be contained.

<Preparation of catalyst>
There are various methods for preparing the catalytic cracking catalyst of the present invention composed of the above components, and the preparation method is not particularly limited. For example, it can be prepared by the following procedure. it can.
First, the above crystalline aluminosilicate, silica binder, and clay mineral are stirred and mixed in a mixed solution to obtain a uniform aqueous slurry. At this time, the mixing ratio of the crystalline aluminosilicate, the silica binder, and the clay mineral is 20 to 50% by mass of the crystalline aluminosilicate, preferably 30 to 50% by mass, and 5 to 5% of the silica binder on the basis of catalyst drying. It is made to fall within the range of 40% by mass, preferably 10-30% by mass, and clay minerals by 10-75% by mass, preferably 30-70% by mass.

  If the amount of crystalline aluminosilicate is 20% by mass or more, the desired decomposition activity can be obtained, and if it is 50% by mass or less, the amount of clay mineral and silica binder is relatively reduced. Therefore, the following undesirable phenomenon can be avoided. That is, if the amount of the clay mineral or the silica binder is too small, not only the catalyst strength is lowered but also the bulk density of the catalyst is reduced, resulting in undesirable results in the operation of the apparatus.

  Further, if the amount of the silica binder is 5% by mass or more, the strength of the catalyst can be maintained, so that undesirable phenomena such as catalyst scattering and mixing in the produced oil can be avoided, and if it is 40% by mass or less. An improvement in catalyst performance commensurate with the amount used is recognized, which is economically advantageous.

  Furthermore, if the amount of the clay mineral is 10% by mass or more, the catalyst strength and the bulk density of the catalyst are small, and it can be avoided that the operation of the apparatus is hindered, and if it is 75% by mass or less, The amount of crystalline aluminosilicate and silica binder is relatively small, the expected amount of decomposition activity cannot be obtained due to the insufficient amount of crystalline aluminosilicate, and the catalyst preparation is not possible due to the insufficient amount of binder. The difficulty can be avoided. And, when the mixing ratio of clay minerals is within the above range, it has high cracking activity, reduces the amount of cracked products such as dry gas, LPG, and coke, and improves the selectivity of gasoline fraction. Thus, it is important to obtain the excellent effect of the present invention that FCC gasoline can be produced efficiently and in high yield.

  The ratio of the solid content in the aqueous slurry prepared by mixing the above components is about 5 to 60% by mass, more preferably 10 to 50% by mass. If the ratio of the solid content is within this range, the amount of water to be evaporated will be appropriate, and there will be no trouble in the spray drying process, etc., and the viscosity of the slurry will be too high, making it difficult to transport the slurry. There is no.

  Next, the prepared mixed slurry of crystalline aluminosilicate / silica binder / clay mineral is usually spray-dried to obtain catalyst particles. The spray drying process is generally performed using a spray drying apparatus at a gas inlet temperature of about 200 to 400 ° C and a gas outlet temperature of about 100 to 200 ° C. In general, the microspheres obtained by spray drying preferably have a particle size of about 20 to 150 μm and a water content of about 10 to 30% by mass.

  The microspheres obtained by spray-drying the above aqueous slurry can be fired at 200 ° C. or higher as necessary to form a fired product, and when spray drying of the aqueous slurry with a spray drying device, In the case where a facility capable of maintaining the gas outlet temperature at 200 ° C. or higher is provided, it is possible to include a microsphere firing step in the spray drying step.

<Catalyst cleaning>
The catalyst microspheres or the calcined product obtained as described above are usually composed of crystalline aluminosilicate, silica binder, soluble impurities from each catalyst component of clay mineral, and alkali metals such as sodium and potassium. Since it is contained, soluble impurities are washed away using water or aqueous ammonia, and then the alkali metal is washed away by ion exchange. When there is no excess sodium or potassium in the obtained microspheres or the fired product thereof, they can be used as a catalyst without being washed away.

  Specifically, alkali metal such as sodium and potassium is removed by washing with ammonium sulfate, ammonium sulfite, ammonium hydrogen sulfate, ammonium hydrogen sulfite, ammonium thiosulfate, ammonium nitrite, ammonium nitrate, ammonium phosphinate, ammonium phosphonate, and phosphoric acid. Ions using aqueous solutions of ammonium salts such as ammonium, ammonium hydrogen phosphate, ammonium dihydrogen phosphate, ammonium carbonate, ammonium hydrogen carbonate, ammonium chloride, ammonium bromide, ammonium iodide, ammonium formate, ammonium acetate, ammonium oxalate Can be exchanged.

  Subsequent to the washing, the microspheres or the calcined product thereof is dried again at a temperature of about 100 to 500 ° C. to adjust the water content to about 1 to 25% by mass, whereby the catalytic cracking catalyst according to the present invention is obtained.

<Catalytic decomposition method>
In the present invention, in order to catalytically crack hydrocarbon oil, hydrocarbon oil (hydrocarbon mixture) boiling in a boiling range of gasoline of 200 ° C. or higher may be brought into contact with the catalytic cracking catalyst of the present invention. The hydrocarbon mixture boiling above the gasoline boiling range means a light oil fraction obtained by atmospheric or vacuum distillation of crude oil, an atmospheric distillation residue oil, and a vacuum distillation residue oil. This includes oil, dehumidified and deasphalted asphalt, tar sand oil, shale oil, and coal liquefied oil.

  In the catalytic cracking on a commercial scale, the above-described FCC catalyst of the present invention is usually continuously fluidized and circulated in a catalytic cracking apparatus composed of two kinds of containers, a vertically installed cracking reactor and a catalyst regenerator. Do it. That is, the hot regenerated catalyst coming out of the catalyst regenerator is mixed with the hydrocarbon oil to be decomposed and guided in the upward direction in the cracking reactor. As a result, the FCC catalyst deactivated by the coke deposited on the catalyst is separated from the decomposition product, and after stripping, it is transferred to a catalyst regenerator. The spent FCC catalyst transferred to the catalyst regenerator is regenerated by removing the coke on the catalyst by air combustion, and is recycled to the cracking reactor. On the other hand, the cracked product separates into dry gas, LPG, gasoline fraction, middle distillate, and one or more heavy fractions such as heavy cycle oil (HCO) or slurry oil. Of course, these heavy fractions can be recycled into the cracking reactor to further proceed the cracking reaction.

The operating conditions of the cracking reactor in the catalytic cracking are as follows: the pressure is normal pressure to 5 kg / cm ² , the temperature is about 400 to 600 ° C., preferably about 450 to 550 ° C., and the weight ratio of catalyst / raw hydrocarbon oil is It is suitable to be about 2-20, preferably about 4-15.

  If reaction temperature is 400 degreeC or more, the decomposition reaction of raw material hydrocarbon oil will advance suitably, and a decomposition product can be obtained suitably. Moreover, if it is 600 degrees C or less, the amount of light gas production | generations, such as dry gas and LPG produced | generated by decomposition | disassembly, can be reduced, and the yield of the gasoline fraction of a target object can be increased relatively, and it is economical. .

If the pressure is 5 kg / cm ² or less, the progress of the decomposition reaction in which the number of moles is increased is hardly inhibited. Further, if the weight ratio of the catalyst / raw hydrocarbon oil is 2 or more, the catalyst concentration in the cracking reactor can be kept moderate, and the decomposition of the raw hydrocarbon oil suitably proceeds. On the other hand, if it is 20 or less, the effect of increasing the catalyst concentration is saturated, and it is possible to prevent disadvantages without obtaining an effect commensurate with increasing the catalyst concentration.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this is only an illustration and does not restrict | limit this invention.

[Analytical equipment, analysis conditions, etc.]
The equipment and calculation formulas used in the analysis of each catalyst and clay mineral used in Examples and Comparative Examples are as follows.
Composition analysis (ICP): “IRIS Advantage” manufactured by Thermo Jarrel Ash

Scanning electron microscope (SEM): Field emission scanning electron microscope “JSM-6340F” manufactured by JEOL Ltd.
Sample preparation: A clay mineral sample was fixed to a sample table using a conductive double-sided tape, and then coated with about 200 mm of Au to prepare a sample for observation.
Analysis method: Taking a secondary electron image by SEM (acceleration voltage: 5 KV).
Method for calculating the number of layers: Shooting dozens of images at different locations at an imaging magnification of 5000 times or more (a magnification at which the number of layers can be analyzed), calculating the number of layers for a total of 100 particles in each image, Distribution and average number of layers were determined.

・ XRD ^* Equipment: “RINT2500V” manufactured by Rigaku Corporation
* Pretreatment: Clay mineral samples were dried at 100 ° C. for 24 hours and then measured under the following conditions.
Tube voltage: 50 kv
Tube current: 200 mA
Scanning mode: Continuous Scanning speed: 2 ° / min
Scan step: 0.02 °
Measurement range (2θ): 5 to 90 °
Divergence, scattering slit: 1 °
Receiving slit: 0.3mm

(Preparation of catalyst)
Example 1 (Preparation of catalyst A)
The stabilized Y-type zeolite having the properties shown in Table 1 as crystalline aluminosilicate, the properties shown in Table 2 as clay minerals, and the crystal shape shown in FIG. 1 in image measurement using a scanning electron microscope (SEM). 3, using clay mineral (a) showing the distribution of the number of layers shown in FIG. 4 (manufactured by Sanyo Clay Industry Co., Ltd .: BI Kaolin) and silica sol (JIS No. 3 water glass, SiO ₂ concentration 20.0 mass%) as a binder, Catalyst A was prepared as follows.

A mixed solution of 138 g of water glass and 176 g of pure water was added dropwise to 94 g of dilute sulfuric acid to prepare an aqueous silica sol solution (SiO ₂ concentration 20.0 mass%). On the other hand, distilled water was added to 69.4 g (dry basis) of a stabilized Y-type zeolite having the properties shown in Table 1 to prepare a zeolite slurry. Clay mineral (a) having the properties shown in Table 2 in the above silica sol aqueous solution and showing the crystal shape of FIG. 1 and the number distribution of stacks of FIGS. 3 and 4 in image measurement using a scanning electron microscope (SEM). 108.5 g (dry basis) and the above zeolite slurry were mixed and further mixed for 5 minutes.
The obtained mixed slurry was spray-dried under conditions of an inlet temperature of 210 ° C. and an outlet temperature of 140 ° C., and the obtained microspheres were used as catalyst precursors. The catalyst precursor was ion-exchanged twice with 3 L of a 5% by mass ammonium sulfate aqueous solution at 60 ° C., and further washed with 6 L of distilled water. Then, it dried at 110 degreeC overnight in the dryer, and the catalyst A was obtained.

Comparative Example 1 (Preparation of catalyst B)
The stabilized Y-type zeolite having the properties shown in Table 1 as crystalline aluminosilicate, the properties shown in Table 2 as clay minerals, and the crystal shape shown in FIG. 2 in image measurement using a scanning electron microscope (SEM). 3. Using a clay mineral (b) showing the distribution of the number of layers in FIG. 4 and silica sol (JIS No. 3 water glass, SiO ₂ concentration 20.0 mass%) as a binder, a catalyst was prepared as follows.

A mixed solution of 138 g of water glass and 176 g of pure water was added dropwise to 94 g of dilute sulfuric acid to prepare an aqueous silica sol solution (SiO ₂ concentration 20.0 mass%). On the other hand, distilled water was added to 69.4 g (dry basis) of a stabilized Y-type zeolite having the properties shown in Table 1 to prepare a zeolite slurry. Clay mineral (b) having the properties shown in Table 2 in the above silica sol aqueous solution and showing the crystal shape of FIG. 2 and the distribution of the number of layers shown in FIGS. 3 and 4 in image measurement using a scanning electron microscope (SEM). 108.5 g (dry basis) and the above zeolite slurry were mixed and further mixed for 5 minutes.
The obtained mixed slurry was spray-dried under conditions of an inlet temperature of 210 ° C. and an outlet temperature of 140 ° C., and the obtained microspheres were used as catalyst precursors. The catalyst precursor was ion-exchanged twice with 3 L of a 5% by mass ammonium sulfate aqueous solution at 60 ° C., and further washed with 6 L of distilled water. Then, it dried at 110 degreeC overnight in the dryer, and the catalyst B was obtained.

[Catalyst composition]
The compositions of the catalysts obtained in Example 1 and Comparative Example 1 are summarized in Table 3.

[Evaluation of catalyst activity]
About each catalyst obtained in Example 1 and Comparative Example 1, respectively, using an ebullated bed microactivity test apparatus (ACE-Model R + manufactured by KAYSER TECHNOLOGY) under the same feedstock and the same measurement conditions as follows: The catalytic cracking properties were tested. That is, as a pretreatment, each catalyst is heated from room temperature to 600 ° C. in 30 minutes and kept at 600 ° C. for 2 hours to approximate each catalyst usage, that is, to equilibrate. After drying, the cyclohexane solution containing nickel naphthenate and vanadium naphthenate is absorbed so that nickel and vanadium become 1000 ppm by mass and 2000 ppm by mass, respectively, dried at 100 ° C., and then increased to 600 ° C. over 30 minutes. The catalyst is heated for 2 hours at 600 ° C. and calcined, and then each catalyst is heated in a flowing state from room temperature to 800 ° C. in 90 minutes in 90 minutes. After reaching 800 ° C., 100% steam is reached. It switched to atmosphere and processed for 6 hours.

  Using the above-equilibrated catalyst, and hydrocarbon oil (desulfurized vacuum gas oil (VGO) 50% + deflow residual oil (DDSP) 50%) having properties shown in Table 4 as a feedstock oil, In an activity test apparatus, an evaluation test was performed with a reaction temperature of 510 ° C., a reaction time of 75 to 150 seconds, and a catalyst / hydrocarbon oil ratio (mass ratio) of 3.0, 4.0, 5.0, 6.0. . The test results were graphed, and from this graph (not shown), the catalyst / hydrocarbon oil ratio (mass ratio) at which the conversion was 60% by mass was calculated by regression calculation. Here, the conversion rate is 100-middle fraction (mass%)-heavy fraction (mass%). Further, Table 5 shows the compositions of the FCC-generated oil calculated by the regression calculation when the conversion is 60% by mass.

The catalyst B obtained in Comparative Example 1 has a low FCC gasoline yield and a large amount of dry gas (hydrogen, C1 to C2), LPG, and coke. And disadvantageous when considering the burden.
However, the catalyst A obtained in Example 1 according to the present invention can reduce the generation amount of dry gas, coke and LPG, and can obtain FCC gasoline in high yield.

  In particular, when the FCC is operated at a high operating rate, by reducing the dry gas, LPG, and coke, the regeneration tower temperature and the gas section can be afforded, so that more efficient operation of the apparatus becomes possible. In addition, since FCC gasoline has a large blending amount with gasoline shipped to the market, if FCC gasoline can be obtained even in a slightly high yield, there is a great economic merit.

It is the figure which observed the clay mineral (a) used in Example 1 with the scanning electron microscope (SEM). It is the figure which observed the clay mineral (b) used in the comparative example 1 with the scanning electron microscope (SEM). It is the number distribution of the lamination | stacking obtained by analyzing the scanning electron microscope (SEM) observation result of the clay mineral (a) used in Example 1 and the comparative example 1 and a clay mineral (b). It is a number distribution (integrated value) figure obtained by analyzing the scanning electron microscope (SEM) observation result of the clay mineral (a) and the clay mineral (b) used in Example 1 and Comparative Example 1.

Claims (2)

In image measurement using a scanning electron microscope, the crystal particles have a plate-like crystal structure, and 10 to 75% by mass of a clay mineral having a property of an average number of layers of 15 to 50, and 20 of a crystalline aluminosilicate. A catalytic cracking catalyst for hydrocarbon oil, comprising ~ 50% by mass and 5-40% by mass of a silica binder as a binder.   A method for catalytic cracking of hydrocarbon oil, wherein the catalytic cracking catalyst for hydrocarbon oil according to claim 1 is used for catalytic cracking of hydrocarbon oil.