JPH0516909B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a catalyst composition for catalytic cracking of hydrocarbons, and more particularly, it relates to a catalyst composition for catalytic cracking of hydrocarbons, and more specifically,
Used in the catalytic cracking of heavy hydrocarbon oils containing large amounts of heavy metals such as nickel, iron, and copper, it exhibits excellent metal resistance, maintains high cracking activity and high gasoline selectivity for a long period of time, and The present invention relates to a catalyst composition that can suppress the production of hydrogen and coke to a low level, and a method for producing the same. [Prior art] Catalytic cracking of hydrocarbons is originally intended for the production of gasoline, so the catalyst used for this must naturally have high cracking activity and high gasoline selectivity. Therefore, metal resistance is required for catalysts for catalytic cracking. The worsening oil situation in recent years has forced the use of low-grade heavy hydrocarbon oil, typically residual oil containing heavy metals such as vanadium, nickel, iron, and copper, as a raw material for catalytic cracking. This makes the metal resistance of catalytic cracking catalysts increasingly important. Generally, during catalytic cracking of heavy hydrocarbon oil,
Due to the deposition of metal contaminants contained in the feed oil on the catalyst, the cracking activity and gasoline selectivity of the catalyst are reduced to a greater or lesser extent. Therefore, the catalysts for catalytic cracking currently in common commercial use, typically catalysts for catalytic cracking in which zeolite is dispersed in a porous inorganic oxide matrix, are somewhat satisfactory even if a certain amount of metal is deposited. Usually, it has enough metal resistance to maintain the desired catalytic performance.
However, when this type of catalyst is used to catalytically crack low-grade heavy hydrocarbon oils such as those mentioned above, the catalyst is also contaminated with a large amount of metal contaminants. is deposited, which promotes the dehydrogenation reaction, increasing the production of hydrogen and coke, and even destroying the crystal structure of the zeolite, making it impossible to fulfill the original purpose of catalytic cracking. Under these circumstances, as a countermeasure when subjecting low-grade heavy hydrocarbon oil with a large amount of metal contaminants to catalytic cracking, the amount of catalyst used is increased to reduce the amount of deposited metal per catalyst particle. Alternatively, measures have been taken to suppress the decrease in catalyst activity caused by deposited metals by adding an antimony compound to the raw oil. However, these operational countermeasures are not practical due to the increased operating costs.
On the other hand, as a measure to improve the performance of the catalyst, it is known that the amount of zeolite dispersed in the catalyst is increased compared to that of a normal catalytic cracking catalyst. A catalyst for catalytic cracking is described in which the metal resistance of the catalyst is improved by incorporating a phosphorus compound into the catalyst. Furthermore, US Pat. No. 4,228,036 discloses a catalyst for catalytic cracking in which zeolite is dispersed in a matrix of alumina-aluminum phosphate-silica. In addition, U.S. Patent No. 3,711,422 describes that adding an antimony compound to a catalytic cracking catalyst inactivates metal contaminants deposited on the catalyst, and U.S. Pat. A method is described for inactivating metal contaminants by contacting a catalyst with deposits of contaminants with a compound such as antimony, bismuth, or phosphorus. [Problems to be solved by the invention] Among the conventional catalysts for catalytic cracking developed to improve the metal resistance of the catalyst, the catalyst with increased zeolite content has the disadvantage that the zeolite itself is expensive. Therefore, it cannot be made into a commercially attractive catalyst. In addition, phosphorus components, antimony,
Catalysts containing deactivating agents such as bismuth also
Its metal resistance is not necessarily satisfactory. According to the knowledge obtained by the present inventors, an alumina-containing catalytic cracking catalyst is used for catalytic cracking of hydrocarbon oil to deposit vanadium, and the spent catalyst is
When analyzed using a line microanalyzer, the distribution of deposited vanadium corresponds well to the distribution of alumina. This fact suggests that by having alumina present in the form of a block within the catalyst for catalytic cracking, metal contaminants can be deposited intensively on the alumina block. [Means for Solving the Problems] The present invention provides a method in which alumina particles having a particle size of 2 to 60μ containing a metal deactivator and a phosphorus component and crystalline aluminosilicate are uniformly dispersed in a porous inorganic oxide matrix. A catalyst composition for catalytic cracking of hydrocarbons is provided. In this catalyst composition, the metal deactivator and the phosphorus component-containing alumina particles are in the range of 5 to 75% by weight, and the crystalline aluminosilicate is in the range of 5 to 75% by weight.
In the range of 50% by weight, the porous inorganic oxide matrix can be adjusted individually in the range of 20-50% by weight. The metal deactivator of the present invention is one selected from Sb, Bi, B, Mn and Sn.
A species or more than one metal component is used. The catalyst composition of the present invention can be produced by spray-drying a slurry of a mixture of alumina particles containing the metal component and phosphorus component, crystalline aluminosilicate, and a matrix precursor. The particle size of the alumina particles containing the metal component and the phosphorus component must be in the range of 2 to 60 microns. This is because if fine alumina particles with a particle size below this range are used, the alumina particles will be uniformly dispersed in the catalyst composition and cannot be unevenly distributed in a block shape. If the particle size exceeds the above range,
This is because it is unfavorable in relation to the average particle size of the catalyst composition finally obtained. Therefore, the metal component and phosphorus component-containing alumina particles of the present invention, for example, have a particle size of 2 to 2, which is prepared in advance.
60μ of alumina or alumina hydrate is brought into contact with an aqueous solution containing phosphate ions (PO ₄ ^3- ) and an aqueous solution containing a metal deactivator, or coarse alumina or alumina hydrate is brought into contact with phosphate ions (PO 4 3- ) and an aqueous solution containing a metal deactivator. It is produced by contacting an aqueous solution containing a metal deactivator with an aqueous solution containing a metal deactivator, drying it, and pulverizing it to a particle size of 2 to 60 μm after firing. When impregnating alumina with a metal deactivator and a phosphorus component, it is possible to simultaneously impregnate both components using a mixed solution of an aqueous solution containing phosphate ions and an aqueous solution containing a metal deactivator. It is also possible to impregnate the components individually. In the latter case, although the order does not matter, it is preferable to dry and fire the alumina once the first impregnation step is completed, and the firing temperature is generally preferably in the range of 250 to 850°C. For example, a previously prepared alumina or alumina hydrate having a particle size of 2 to 60 μm is brought into contact with an aqueous solution containing a metal deactivator, then dried and fired at a temperature of 250 to 850°C. There is a method of introducing a phosphorus component into the alumina particles by then bringing them into contact with an aqueous solution containing phosphate ions. In any case, each aqueous solution of phosphoric acid, ammonium hydrogen phosphate, ammonium phosphate, phosphate ester, or a mixture thereof can be used as the phosphate ion-containing aqueous solution. Furthermore, as the metal deactivator-containing aqueous solution, aqueous solutions of antimony, bismuth, tin, and manganese nitrates, carbonates, and chlorides, and boric acid aqueous solutions can be used. The amount of phosphorus introduced into the alumina particles by contact with an aqueous solution containing phosphate ions is 0.6 to 12.2% by weight of the alumina as elemental phosphorus (P/Al atomic ratio = 0.01 to 12.2% by weight of the alumina).
0.20) is allowed. This is because if the content is below this range, the effect of containing phosphorus will not be achieved, and if it is above this range, the pore volume of the alumina will decrease too much, which is not preferable. On the other hand, the amount of metal deactivator is preferably in the range of 0.001 to 5% by weight of the alumina as elemental metal.
It is preferable that the metal deactivator and the phosphorus component are strongly fixed to the alumina by firing after introducing the metal deactivator and the phosphorus component. The crystalline aluminosilicate zeolite of the present invention includes synthetic Y-type zeolite, mordenite,
ZSM type zeolites, natural zeolites, etc. can be used, and these are used in the form of ion exchange with cations selected from hydrogen, ammonium, and polyvalent metals, as in the case of ordinary catalysts for catalytic cracking. As the porous inorganic oxide, silica, silica-alumina, silica-magnesia, etc. can be used, and matrix components commonly used in ordinary catalysts for catalytic cracking can also be used in the present invention. The catalyst composition of the present invention can be produced by a method similar to the method for producing a conventional crystalline aluminosilicate zeolite-containing catalyst for catalytic cracking, except that the specific alumina particles as described above are used. That is, the catalyst composition of the present invention comprises a precursor slurry of a porous inorganic oxide matrix, such as a silica hydrosol, a silica-alumina hydrosol, etc., containing the above-mentioned alumina particles having a particle size of 2 to 60 microns, and a crystalline aluminosilicate. It can be prepared by adding zeolite and uniformly dispersing it, and spray-drying the resulting mixture slurry in a conventional manner. and a matrix precursor slurry;
The amounts of the metal deactivator, the phosphorus component-containing alumina particles, and the crystalline aluminosilicate zeolite are such that the final catalyst composition contains the above alumina particles in an amount of 5 to 75% by weight. It is adjusted to contain zeolite in a range of 5 to 50% by weight and matrix in a range of 20 to 50% by weight, respectively. Then, the spray-dried particles are washed as necessary, and after washing, they are dried again. [Function] In the catalytic cracking reaction of hydrocarbon oil, metal contaminants such as vanadium and nickel contained in the feedstock oil are deposited on the catalyst, reducing the cracking activity and gasoline selectivity of the catalyst. The dehydrogenation reaction significantly increases the amount of coke and hydrogen produced. In particular, vanadium moves near the crystalline aluminosilicate zeolite in a catalyst regeneration atmosphere where the temperature is normally maintained at 630° C. or higher and destroys its crystal structure. The catalyst composition for catalytic cracking of the present invention has alumina particles fixed with a metal deactivator and a phosphorus component,
Since it is dispersed in the composition in the form of blocks with a particle size of 2 to 60 microns, metal contaminants deposited on the catalyst are captured by the particles and aggregated, and are not dispersed in the composition. Therefore, even in a catalyst regeneration atmosphere maintained at 630° C. or higher, the movement of deposited metals, especially vanadium, to the vicinity of the crystalline aluminosilicate zeolite is hindered, and as a result, the destruction of its crystal structure is suppressed. It is also presumed that the phosphorus introduced into the alumina promotes the aggregation of metals such as vanadium and nickel captured on the alumina, and promotes the inactivation of these metals. Furthermore, a metal deactivator consisting of one or more metal components selected from antimony, bismuth, boron, manganese, and tin easily forms a solid solution with metals such as vanadium and nickel, and as a result, especially Significantly suppresses the dehydrogenation activity of nickel. Since these metal deactivators are fixed to the alumina particles, they do not inhibit the activity of the catalyst. Thus, the catalyst composition of the present invention can maintain high cracking activity and high gasoline selectivity even when a large amount of metal contaminants are deposited, and can suppress the production of coke and hydrogen to a small amount. Example 1 Aluminum hydroxide obtained by the Bayer method was calcined in air at 600°C for 2 hours. Next, 500 g of this calcined alumina was weighed out, and an aqueous phosphoric acid solution prepared by diluting 82 g of orthophosphoric acid with a concentration of 85% with water to make 115 ml was added to the calcined alumina and blended for 10 minutes. The phosphoric acid-added alumina particles were dried at 110°C for 17 hours and then calcined at 600°C for 1 hour to prepare phosphorus-containing alumina particles. The average particle size of these phosphorus-containing alumina particles is 30μ, and the phosphorus content is 4.2% by weight.
(The atomic ratio of P/Al was 0.07). This phosphorus-containing alumina particle corresponds to 1.2% by weight of Sb.
After adding and stirring an aqueous solution of _SbCl3 , 110℃
The powder was dried for 17 hours at 600°C and further calcined for 2 hours to prepare antimony and phosphorus-containing alumina particles. 5% by weight prepared by adding sulfuric acid to water glass
500 g of the antimony-fixed phosphorus-containing alumina particles described above were added to 4000 g of silica hydrosol containing SiO ₂ , and 300 g of hydrogen ion-exchanged Y-type crystalline aluminosilicate (zeolite) was added to form a mixed slurry. This mixed slurry was then spray-dried, washed, and further dried to obtain the catalyst composition for catalytic cracking of the present invention. This catalyst composition consists of 50% by weight of antimony and phosphorus-containing alumina particles, 30% by weight of H-Y type zeolite, and 20% by weight of silica derived from the matrix.
It contained. This catalyst composition was used as catalyst A.
shall be. Example 2 Example 1 except that a Bi(NO ₃ ) ₂ aqueous solution corresponding to 1.2% by weight of Bi was used instead of the SbCl ₃ aqueous solution.
A catalyst composition was prepared in the same manner as above. This catalyst composition contains 4.98% by weight of P ₂ O ₅ , 0.67% by weight of Bi ₂ O ₃ ,
This catalyst contains 44.4% by weight of Al ₂ O ₃ and is designated as Catalyst B. Comparative Example 1 Example 1 except that no SbCl ₃ aqueous solution was used.
A catalyst composition was obtained in the same manner as above. This catalyst contained 50% by weight of phosphorus-containing alumina particles and 30% by weight of zeolite. This product is designated as catalyst C. Comparative Example 2 An aluminum sulfate solution was neutralized with aqueous ammonia, and the resulting aluminum hydroxide precipitate was washed to remove by-product salts. To this alumina hydrogel slurry, corresponding to an amount of 490 g as Al ₂ O ₃ , 85
% orthophosphoric acid was added with stirring. To this slurry, 4000 g of silica hydrosol with an SiO ₂ concentration of 5 wt % prepared by adding sulfuric acid to water glass was added, and 300 g of H-Y type zeolite was further added to prepare a mixed slurry. This slurry was then spray dried in the same manner as in Example 1. After immersing this spray-dried product in an aqueous SbCl ₃ solution at a temperature of 50°C for 10 minutes,
It was washed with water and dried to obtain a catalyst composition for catalytic cracking. This catalyst composition contains _4.95 % by weight of _P2O5 and _{Sb2O3 .}
It contained 0.72% by weight and 44.3% by weight of Al ₂ O ₃ . This is designated as catalyst D. Example 3 (Catalyst usage example) For each of the above catalysts A to D, ASTM
Performance evaluation was performed using MAT. First, in order to examine metal resistance, nickel alone or both nickel and vanadium were deposited on each catalyst as follows. That is, each catalyst was preliminarily calcined at 600°C for 1 hour, and then a predetermined amount of a benzene solution of nickel naphthenate or a benzene solution of nickel naphthenate and vanadium naphthenate was absorbed into each catalyst, and then dried at 110°C and then heated at 600°C. at °C
Bake for 1.5 hours. After that, in order to achieve pseudo-equilibrium,
Each catalyst was steam-treated at 770°C for 6 hours and then heated again at 600°C.
It was baked at ℃ for 1 hour. Further, each catalyst on which nickel and vanadium were not deposited was also subjected to steam treatment at 770°C for 6 hours for pseudo-equilibrium, and then calcined at 600°C for 1 hour. Using each catalyst pretreated in this way,
ASTM MAT evaluation test was conducted. Display the results -
Shown in 1. Incidentally, the reaction conditions are as follows. Raw material oil: Desulfurized vacuum gas oil Reaction temperature: 482℃ Space velocity: 16hr ^-1 Catalyst/oil ratio: 3 (weight)

[Table] As shown in Table-1, catalysts A, B, and
C is the conversion rate after nickel and vanadium deposition, compared to catalyst D, which is a catalyst made of zeolite and a matrix in which P ₂ O ₅ , Al ₂ O ₃ and SiO ₂ are uniformly mixed, and impregnated with an antimony compound; High gasoline yield, low coke and hydrogen production. Furthermore, catalysts A and B have higher conversion rates and higher gasoline yields than catalyst C which does not contain a metal deactivator. [Effects] The catalyst composition for hydrocarbon catalytic cracking of the present invention exhibits high cracking activity and high gasoline selectivity even when a large amount of metal contaminants are deposited on the catalyst, and reduces the amount of coke and hydrogen produced. can be reduced to a level.

Claims (1)

[Claims] 1. Hydrocarbon catalytic cracking in which alumina particles with a particle size of 2 to 60 μm containing a metal deactivator and a phosphorus component and crystalline aluminosilicate zeolite are uniformly dispersed in a porous inorganic oxide matrix. Catalyst composition for use. 2 The above metal deactivators are Sb, Bi, B, Mn
The catalyst composition according to claim 1, which is one or more metal components selected from Sn and Sn. 3 The amount of metal deactivator contained in the alumina particles is 0.001 to 0.001 of the alumina particles as elemental metal.
5% by weight of the catalyst composition of claim 1. 4 The amount of phosphorus contained in the alumina particles is 0.6 to 12.2% by weight of the alumina particles as elemental phosphorus.
The catalyst composition according to claim 1. 5 5 to 75% by weight of the alumina particles containing the metal deactivator and phosphorus component, 5 to 50% by weight of the crystalline aluminosilicate zeolite, and 20 to 50% by weight of the porous inorganic oxide matrix. A catalyst composition according to claim 1 containing. 6 Particle size 2 to 2 containing a metal deactivator and a phosphorus component in a porous inorganic oxide precursor slurry
A method for producing a catalyst composition for catalytic cracking of hydrocarbons, which comprises mixing 60μ alumina particles and crystalline aluminosilicate zeolite and spray-drying the resulting mixed slurry. 7 The above metal deactivators are Sb, Bi, B, Mn
7. The method according to claim 6, wherein the metal component is one or more metal components selected from Sn and Sn. 8 The amount of metal deactivator contained in the alumina particles is 0.001 to 0.001 of the alumina particles as elemental metal.
7. The method of claim 6, wherein the amount is 5% by weight. 9 The amount of phosphorus contained in the alumina particles is 0.6 to 12.2% by weight of the alumina particles as elemental phosphorus.
The method according to claim 6.