JP3335518B2 - Method for calcining ammonium ion-exchanged zeolite Y and catalyst for catalytic cracking of hydrocarbon oil containing calcined zeolite Y - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for calcining ammonium ion-exchanged zeolite Y and a catalyst for catalytic cracking of hydrocarbon oils containing calcined zeolite Y. The present invention relates to a method for calcining ammonium ion-exchanged zeolite Y, which is capable of producing zeolite Y exhibiting selectivity and producing less coke and exhibiting excellent properties for decomposing heavy oil components, and catalytic cracking of hydrocarbon oil containing zeolite Y. Regarding the catalyst.

[0002]

2. Description of the Related Art Zeolite Y (fojasite type zeolite), which is widely used as a fluid catalytic cracking catalyst for hydrocarbon oils, has a SiO ₂ / Al ₂ O ₃ ratio of 3.5.
The above-mentioned crystalline aluminosilicate is synthesized, and the synthetic zeolite is synthesized as an alkali metal or an alkaline earth metal as a cation species, particularly as a sodium type. However, since the sodium type does not exhibit the activity of decomposing hydrocarbons, it is usually used after being ion-exchanged to an ammonium type, a polyvalent metal type or a rare earth metal type.

Further, there has been reported a method for producing a faujasite-type zeolite having excellent thermal stability, in which the unit cell of zeolite Y is reduced and the molar ratio of silica / alumina having a zeolite skeleton is increased.

For example, Japanese Patent Publication No. 57-16925 discloses that an ammonium-sodium type zeolite Y containing about 0.5 to 5% by weight of sodium as Na ₂ O is calcined, and the calcining is carried out at about 315.6 to 50%. 898.9 ° C (600 to 1
At least about 0.014 kg / cm at a temperature of 650 ° F.
² (0.2 psi) water vapor was contacted with the zeolite for a period of time sufficient to significantly reduce the size of the zeolite unit cell to a value of about 24.40-24.64 angstroms and was then calcined. The zeolite is replaced with ammonium ions for at least about 25% of the remaining zeolite sodium ions and less than about 1% by weight of Na ₂ O
Characterized in that it is further subjected to an ammonium ion exchange treatment under conditions prepared to obtain a final product containing
A method for making the composition is described.

Further, Japanese Patent Publication No. 44-31948 discloses that
At high temperature in a gas phase containing 5% or more moisture,
Treating the alumina for a time sufficient to remove at least some alumina tetrahedra from the crystal lattice of the molecular sieve turns the alumina into an amorphous phase in the molecular sieve, and the heat-treated molecular sieve to remove alumina. Contacting with a suitable agent to thereby produce an aluminosilicate zeolite molecular sieve having an enhanced silica / alumina molar ratio, whereby at least the crystallinity of the molecular sieve is substantially retained. A method for increasing the molar ratio of silica / alumina in the crystal lattice of a molecular sieve-type crystalline aluminosilicate zeolite in which the molecular sieve is at least partially in the hydrogen form is disclosed. further,
JP-A-60-46916 discloses a method for producing a zeolite having high hydrothermal stability, in which an ammonium-exchanged faujasite-type zeolite is calcined at a temperature of 400 to 600 ° C., and is then subjected to a pH of 2 to 4.5. A method of treating with an aqueous solution of ammonium salt, further exchanging ammonium ions, and then calcining has been proposed.

Further, Japanese Patent Publication No. 5-66324 discloses a method for calcining a faujasite type zeolite having an ammonium exchange rate of 50% or more, wherein ammonia gas and water vapor generated from the zeolite are converted into a zeolite in a rotary calcining furnace. There has been proposed a method for calcining faujasite-type zeolites, which comprises evacuating in the same direction as the flow direction and maintaining the water vapor partial pressure at 10% or more. Another method is to calcine ammonium-type zeolite Y in the presence of a rapid steam flow (Japanese Patent Publication No. 46-913).
No. 2), a method of calcining ammonium zeolite Y having a cation content of 3.3 equivalent% or less at 725 to 870 ° C. in a steam environment of 0.2 to 10 atm (Japanese Patent Laid-Open No. 54-122700). JP-A-58-167420, and a method in which faujasite is treated with a strongly acidic cation exchange resin, then brought into contact with aqueous ammonia, and then calcined at 500 to 800 ° C.

Generally, the starting material zeolite Y is SiO
_{Because of the} low ₂ / Al ₂ O ₃ molar ratio (Caban ratio), the conventional method of firing at a high temperature in a steam atmosphere uses SiO ₂
Although the / Al ₂ O ₃ ratio increased, the structural breakdown of zeolite Y was inevitable. Zeolite Y SiO ₂ / Al ₂
It is well known that increasing the O ₃ ratio increases heat resistance, hydrothermal resistance, acid resistance, etc., but the conventional method involves structural destruction of zeolite Y, and the crystallinity and specific surface area of zeolite as a starting material are reduced. It is low in comparison with Y, and when used as an active species of a catalytic cracking catalyst, there is a problem that amorphous silica-alumina generated by the structural destruction of zeolite Y lowers the catalytic activity and selectivity of zeolite Y. Was.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for calcining an ammonium ion-exchanged zeolite Y which can reduce the structural destruction of zeolite Y and can increase the SiO ₂ / Al ₂ O ₃ ratio.

Another object of the present invention is to use the catalytic cracking of hydrocarbon oils, especially heavy hydrocarbon oils, to have high residua resolution, high activity, gasoline and kerosene oil fractions (LCO). It is an object of the present invention to provide a hydrocarbon oil catalytic cracking catalyst having a high liquid yield and low coke generation.

[0010]

SUMMARY OF THE INVENTION The method for calcining ammonium ion-exchanged zeolite Y according to the present invention comprises calcining ammonium ion-exchanged zeolite Y in a partial pressure of steam of 10% or more (first calcining step), and then reducing the calcining temperature. Is fired at a high temperature and in a water vapor partial pressure of less than 10% (second firing step).

[0011] The temperature in the first firing step is 250 to 50.
0 ° C., and the temperature of the second firing step is 400-90.
0 ° C., and the second firing temperature is the first firing temperature.
It is desirable that the temperature is higher than the firing temperature by 150 ° C. or more, preferably 300 ° C. or more.

Further, the catalyst for catalytic cracking of hydrocarbon oil according to the present invention is characterized in that zeolite Y obtained by calcining ammonium ion-exchanged zeolite Y as described above is dispersed in an inorganic oxide matrix. I have.

[0013]

DETAILED DESCRIPTION OF THE INVENTION The method for calcining ammonium ion-exchanged zeolite Y according to the present invention and the catalyst for catalytic cracking of hydrocarbon oil using zeolite Y obtained in this way will be described below in detail.

As the ammonium ion-exchanged zeolite Y used in the present invention, a natural or synthetic zeolite can be used. Specifically, the ratio of SiO ₂ / Al ₂ O ₃ is about 3 to
Na zeolite Y (Na containing sodium about 10 to 14 wt% as Na ₂ O with the 6-range
An ammonium ion-exchanged zeolite in which the Na ₂ O content is reduced by exchanging Na of (Y) with ammonium ions is used.

In order to exchange Na of the Na type zeolite Y for ammonium ions, NH ₄ Cl, NH ₄ NO ₃ , (N
The reaction can be carried out by an ordinary method using an aqueous solution of an ammonium salt such as H ₄ ) ₂ SO ₄ .

The ammonium ion-exchanged zeolite Y calcined in the present invention preferably has a Na ₂ O content of 6% by weight or less, preferably 3 to 6% by weight. N
When the content of a ₂ O is more than 6% by weight, the unit cell constant (UCD) of the obtained zeolite Y tends to hardly decrease and the SiO ₂ / Al ₂ O ₃ ratio tends to hardly increase upon firing. If the content is lower than 3% by weight, the structural breakage of zeolite Y obtained at the time of firing may easily occur.

In the method of the present invention, the above-mentioned ammonium ion-exchanged zeolite Y is fired in a steam partial pressure of 10% or more (first firing step). In the first calcination step, the aluminum in the zeolite framework is dealuminated by calcining the ammonium ion-exchanged zeolite Y in a steam atmosphere. At this time, if the calcination temperature is too high, the obtained zeolite Y May cause structural destruction.

For this reason, the temperature in the first firing step is from 250 to
It is desirably in the range of 500 ° C, preferably in the range of 250 to 400 ° C. If the sintering temperature is higher than 500 ° C., the resulting zeolite Y tends to undergo structural destruction, and if it is lower than 250 ° C., the rate of dealumination may be slow.

In the first calcination step, a partial pressure of steam sufficient to cause dealumination from the zeolite framework is required, and the partial pressure of steam is 10% or more, preferably 20% or more.
%, More preferably 30 to 50%. The firing time is a time sufficient to cause dealumination from the zeolite skeleton, usually 0.2 to 20 hours, preferably 0.4 to 10 hours.

Next, the zeolite calcined in the first calcining process is calcined at a higher temperature than the first calcining process and at a partial pressure of water vapor of less than 10% (second calcining process).

In the second baking process, mainly in the first baking process, silicon (Si) existing in the vicinity moves to the location of the dealuminated lattice defect from the zeolite skeleton to reduce the zeolite lattice defect. And the resulting zeolite Y structure is expected to be stable. It is necessary that the partial pressure of water vapor in the second firing step is less than 10%. When the water vapor partial pressure is more than 10%, dealumination from the zeolite framework occurs in a large amount, so that the structural breakdown of the zeolite may occur. The water vapor partial pressure is preferably 5% or less, more preferably 0.1 to 3%. The temperature of the second firing step is in the range of 400 to 900 ° C., preferably 50 ° C.
It is desirable to carry out in the range of 0 to 800 ° C. When the sintering temperature is lower than 400 ° C., the moving speed of silicon (Si) becomes slow, and when it is higher than 900 ° C., the zeolite structure tends to be broken.

The temperature in the second firing step is higher than the temperature in the first firing step by 150 ° C. or more, preferably 300 ° C. or more, and more preferably 350 to 400 ° C. The firing time in the second firing step is usually 0.2.
-5 hours, preferably 0.4-3 hours.

The ammonium ion-exchanged zeolite Y according to the present invention is calcined by a usual calcining apparatus, for example, a stationary type.
It can be carried out in a batch mode or a continuous mode using a rotary or fluid type baking furnace.

Next, the catalyst for catalytic cracking of hydrocarbon oil of the present invention will be described. The hydrocarbon oil catalytic cracking catalyst of the present invention is obtained by dispersing zeolite Y obtained by calcining ammonium ion-exchanged zeolite Y as described above in an inorganic oxide matrix. As the inorganic oxide matrix, those used in ordinary catalyst compositions for catalytic cracking of hydrocarbons can be used. Specifically, silica,
Conventional inorganic oxide matrices which act as binders such as silica-alumina, alumina, silica-magnesia, alumina-magnesia, phosphorus-alumina, silica-zirconia, silica-magnesia-alumina are used.
Such an inorganic oxide matrix also includes clays such as kaolin, halloysite, and montmorillonite, and metal scavengers such as calcium aluminate.

In such a catalyst for catalytic cracking of hydrocarbon oil, the above-mentioned zeolite Y contains 5 to 50% by weight, preferably 10 to 50% by weight.
In an amount of 40% by weight, the inorganic oxide matrix is 95-5
It is desirably contained in an amount of 0% by weight, preferably 90 to 60% by weight.

The catalyst for catalytic cracking of hydrocarbon oil according to the present invention comprises:
The zeolite Y obtained by calcining the ammonium ion-exchanged zeolite Y as described above and the precursor of the inorganic oxide matrix are uniformly mixed, and the resulting mixture is spray-dried into fine spherical particles. And then dried and calcined. Further, if necessary, rare earths (rare earths) can be introduced into the microspherical particles. The catalyst thus obtained is used in a method for catalytically cracking hydrocarbons.

[0027]

EFFECT OF THE INVENTION Ammonium ion exchanged zeolite Y
Zeolite Y (US) obtained by firing as described above
Y) shows that the unit cell constant is reduced and the crystal skeleton SiO 2_Two/
Al_TwoO _ThreeHigh crystallinity despite increased ratio
When used as a catalyst for catalytic cracking of heavy hydrocarbon oils
It shows excellent cracking activity and gasoline production selectivity.

Surprisingly, zeolite Y obtained according to the present invention has a lower residual oil (bottom) than zeolite Y obtained by calcining ammonium ion-exchanged zeolite Y in a hydrothermal atmosphere by a conventionally known method. Was found to be very excellent in the selective resolution of In zeolite Y obtained by a conventionally known method for firing ammonium ion-exchanged zeolite Y, structural destruction occurs during firing, and the resulting amorphous silica-alumina causes a decrease in catalytic activity or a decrease in selectivity. On the other hand, zeolite Y obtained by calcining ammonium ion-exchanged zeolite according to the method of the present invention has less structural destruction, so that hydrogen and coke are less generated, and a zeolite having the above-mentioned effects is obtained. Can be

[0029]

EXAMPLES Hereinafter, the present invention will be described based on examples, but the present invention is not limited to these examples.

[0030]

Example 1 [Zeolite firing method] The SiO ₂ / Al ₂ O ₃ ratio was 5.0.
And a faujasite-type zeolite (Na-zeolite Y) having a unit cell constant of 24.70 angstroms using a 10% by weight aqueous solution of ammonium sulfate.
Ion exchange at 80 ° C., further washing with warm water, Na ₂ O
Ammonium-exchanged zeolite Y having a content of 5.2% by weight
Was prepared.

The crystallinity of this ammonium-exchanged zeolite Y determined by X-ray diffraction (Union Carbide, SK
The relative crystallinity with respect to −40) was 100%, and the specific surface area was 670 m ² / g.

The obtained ammonium-exchanged zeolite Y
Was heated to 350 ° C. in a stationary electric furnace in the presence of a steam flow having a partial pressure of water vapor of 30%, and then heated at 350 ° C. for 1 hour.
The first baking process was performed by baking for an hour.

The primary fired zeolite Y thus obtained is then heated to 670 ° C. over 2 hours in an atmosphere with a steam partial pressure of 2% in the furnace, and further heated at 670 ° C. for 30 hours. The second baking process was performed by baking for minutes.

Table 1 shows the properties of the obtained zeolite Y (Z-1).

[0035]

[Example 2] [Zeolite firing method] Except that the temperature of the second firing step was changed to 720 ° C using the ammonium-exchanged zeolite Y obtained in Example 1, the procedure was the same as in Example 1. Zeolite Y was prepared. Zeolite Y obtained
Table 1 shows the properties of (Z-2).

[0036]

Comparative Example 1 In this comparative example, a general method for producing USY zeolite is shown. Using the ammonium-exchanged zeolite Y before calcination obtained in Example 1, in the presence of a steam flow having a water vapor partial pressure of 30%, the temperature was raised to 670 ° C. over 2 hours at a substantially constant rate, and further heated to 670 ° C. For 30 minutes.

Table 1 shows the properties of the obtained zeolite Y (Z-3).

[0038]

Examples 3 to 4 and Comparative Example 2 [Preparation of catalytic cracking catalyst] Silica hydrosol 80 containing 12.5% by weight of SiO ₂ prepared by adding sulfuric acid to water glass
Then, 2500 g of kaolin clay (dry basis) was added to 00 g, and the zeolite Y (Z-1, Z-2, Z-3) obtained in Examples 1 and 2 and Comparative Example 1 was added to each of 1 g.
500 g (dry basis) was added to obtain a mixed slurry.

After spray-drying and washing these mixed slurries, a rare earth (RE ₂ O ₃ ) was supported by a 0.5% by weight ion exchange method. This is dried and Z-1, Z-2, Z-
C-1 (Example 3), C-2 (Example 4) and C-
3 (Comparative Example 2) was obtained. [Catalyst Performance Evaluation Test] Performance evaluation tests were performed on the catalyst compositions C-1 (Example 3), C-2 (Example 4) and C-3 (Comparative Example 2) prepared as described above. .

In the performance evaluation test, about 200 g of each catalyst composition was calcined in air at 600 ° C. for 2 hours, and the sample was impregnated with a toluene solution containing 4500 ppm of nickel naphthenate and vanadium naphthenate as V + Ni per catalyst weight, Then, after removing toluene under reduced pressure, 600
Baked for 2 hours at 100 ° C.
The test was carried out using a catalyst equilibrated at 80 ° C. for 13 hours.

The catalytic cracking reaction was carried out under the following reaction conditions using reduced pressure gas oil (DSVGO) obtained by hydrotreating the feedstock oil. Table 2 shows the evaluation results.

K is a reaction rate constant represented by the following equation. K = conversion / (100-conversion) respectively H ₂ / K, the catalyst C-1 according to the present invention as seen at the indicated hydrogen and coke selectivity in Coke / K, C
At -2, the amount of hydrogen and coke generated is suppressed.

FIG. 1 shows the conversion rate of the feed oil and the LCO
(Decomposed light oil) and HCO ⁺ (decomposed heavy oil) yield. The catalysts C-1 and C-2 according to the present invention have excellent LCO selectivity, low HCO ⁺ (cracked heavy oil) production, and improved bottom cracking properties.

[0044]

[Table 1]

[0045]

[Table 2]

[Brief description of the drawings]

FIG. 1 shows the conversion rate and the LC when catalytic cracking of vacuum gas oil was carried out using the catalyst of the present invention and a conventionally known catalyst.
It is a figure which shows the relationship with the yield (wt%) of O and HCO ⁺ .

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Morio Fukuda 13-2 Kitaminato-cho, Wakamatsu-ku, Kitakyushu-shi, Fukuoka Prefecture Inside the Wakamatsu Plant (72) Inventor Seiji Arakawa Wakamatsu, Kitakyushu-shi, Fukuoka 13-2 Kitaminato-cho, Ward Catalysis Chemical Industry Co., Ltd. Wakamatsu Plant (72) Inventor Mitsuru Oi 1134-2 Gongendo, Satte City, Saitama Prefecture Cosmo Research Institute, Inc. R & D Center (72) Inventor Tadashi Tanno 1134-2 Gongendo, Satte-shi, Saitama Pref. Cosmo Research Institute, Inc. R & D Center (72) Inventor Kazuhito Sato 1134-2, Gongendo, Satte-City, Saitama Pref. References JP-A-58-208130 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01J 21/00-38/74 C01B 33/20-39/54 C10G 11/05

Claims (3)

(57) [Claims] 1. When calcining an ammonium ion-exchanged zeolite Y, the zeolite Y is used in an amount of 250 to 400.
C. and in a steam partial pressure of 10% or more (first firing step), and then firing at a higher temperature and a steam partial pressure of less than 10% (second firing step) A method of calcining ammonium ion-exchanged zeolite Y. 2. A temperature of the second sintering process is 400 to 900 ° C.
2. The method for calcining ammonium ion-exchanged zeolite Y according to claim 1, wherein 3. A catalyst for catalytic cracking of hydrocarbon oils, wherein zeolite Y obtained by the method for calcining ammonium ion-exchanged zeolite Y according to claim 1 or 2 is dispersed in an inorganic oxide matrix.