JPS591088B2 - Catalyst composition for hydrocarbon decomposition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a catalyst composition used for catalytic cracking of hydrocarbons. The present invention relates to a new catalyst composition for catalytic cracking that has stability against catalytic cracking and excellent abrasion resistance.

Inorganic oxide catalysts such as silica-alumina, silica-magnesia, silica-zirconia, and alumina-boria are known as catalysts for catalytic cracking of hydrocarbons, and among these, silica-alumina is the most practical catalyst. It is widely used in fluid catalytic cracking processes.

In addition, suitable inorganic oxides or mixtures thereof may be used.
Catalytic cracking catalysts in which crystalline aluminosilicate is dispersed in flux are also known.

The present invention aims to provide a novel catalyst for catalytic cracking that exceeds conventional catalysts in terms of cracking activity, gasoline selectivity, stability against heat and steam, and wear resistance.

Catalysts used for catalytic cracking of hydrocarbons must inherently have cracking activity and gasoline selectivity, but in addition, they must also have stability against heat and steam and wear resistance.

In the catalytic cracking process of hydrocarbons, it is customary to regenerate a catalyst that has been poisoned by precipitation of carbonaceous substances, and then subject the regenerated catalyst to the catalytic cracking reaction again. The process involves stripping hydrocarbons adhering to the catalyst with steam, and then burning the carbonaceous material on the poisoned catalyst in the presence of oxygen.

Therefore, if the thermal and steam stability of the catalyst is insufficient, the activity of the catalyst will be impaired during regeneration, and the regenerated catalyst will have significantly lower cracking activity and gasoline selectivity than the fresh catalyst. be.

In addition, it is customary in most modern catalytic cracking to use a fluidized bed reactor, but if the catalyst does not have sufficient wear resistance, the catalyst will be pulverized in the fluidized bed and lost to the outside of the system. This is also a factor that impairs the cracking activity and gasoline selectivity of the catalyst.

Therefore, it is important for catalysts for catalytic cracking of hydrocarbons to not only have high cracking activity and gasoline selectivity, but also to have high stability against heat and steam, and sufficient wear resistance. It can be said that this is a requirement.

The inventors of the present invention have spent months researching the development of a new catalyst for catalytic cracking that outperforms the performance of conventional catalysts for catalytic cracking.As a result, surprisingly, they have found that crystallization using heat-resistant inorganic oxides and X-ray diffraction method A composition composed of alumina (herein referred to as crystalline alumina) that can be detected as a crystalline alumina has a performance that exceeds that of conventional inorganic oxide catalysts. It has also been found that a catalyst in which crystalline aluminosilicate is dispersed has higher performance than the conventional catalyst containing crystalline aluminosilicate.

In other words, the presence of crystalline alumina not only improves the thermal and steam stability of the catalyst, but also increases the gasoline yield without sacrificing cracking activity, and also increases the wear resistance of the catalyst. It was discovered.

Therefore, the composition according to the present invention is composed of alumina and another inorganic oxide, and the amount of crystalline alumina in the composition is 10
It is characterized by being in the range of ~85 weight ratio.

If the amount of crystalline alumina is below the lower limit of the above range, the significance of the presence of crystalline alumina in the composition is lost, and if it is above the upper limit, the dehydrogenation activity of the composition exceeds the catalytic cracking activity.
The amount of crystalline alumina in the composition can range from 10 to 85 parts by weight.

The composition of the present invention is required to contain an inorganic oxide other than alumina.

As this type of inorganic oxide, in addition to silica, magnesia, titania, zirconia, and boria, one or more of silica-alumina, silica-magnesia, silica-zirconia, alumina-boria, etc. can be used. .

Just to be sure, although conventionally known silica-alumina and alumina-boria originally contain alumina, crystalline alumina, which can be detected by X-ray diffraction, does not contain any alumina. do not have.

Therefore, even when using silica-alumina or alumina-boria, other sources of crystalline alumina must be sought in preparing the compositions of the present invention.

As such an alumina source, it is recommended to use Bayer process aluminum hydroxide (gibbsite), bayerite, boehmite, and χ-2ρ-2η-2γ-alumina.

Another requirement of the compositions of the present invention is that they contain 10 to 85% by weight alumina detectable as crystalline by X-ray diffraction.

In this case, the crystalline alumina may have any crystal form.

However, the amount of crystalline alumina can be determined by preparing a calibration curve using X-ray diffraction method in advance, depending on the type of crystalline alumina source used in preparing the composition and the contents of the composition preparation method. It is possible to quantify by

To further elaborate on this point, the composition of the present invention is generally produced by adding the above-described crystalline alumina source to a hydrosil or hydrogel of an inorganic oxide other than alumina, and typically spray-drying the mixture after aging. However, even if the same amount of the same crystalline alumina source is used, the amount of crystalline alumina in the final composition will vary depending on the above-mentioned changes in the aging conditions and spray drying conditions.

Therefore, in order to accurately quantify the crystalline alumina in the composition of the present invention, individual calibration curves must be prepared for each crystalline alumina source used, each aging condition, and each drying condition. However, it is preferable to quantify the amount of crystalline alumina in the composition using the calibration curve.

The compositions of the present invention are prepared in substantially the same manner as conventional inorganic oxide catalysts for catalytic cracking of hydrocarbons, except that a source of crystalline alumina is additionally added at some stage in the preparation of the composition. be able to.

As mentioned above, the crystalline alumina source can be added to hydrosil or hydrogel of inorganic oxides other than alumina, and can also be added to an aqueous inorganic salt solution before hydrosil is generated, such as an aqueous alkali silicate solution, an aqueous aluminum sulfate solution, or an aqueous alkali aluminate solution. It can be added to etc.

In this case, the crystalline alumina source may be added in powder form or as a suspension.

It is preferable for the particle size of the crystalline alumina source to be as fine as possible in terms of dispersibility and wear resistance of the final composition, but if it is below the average particle size of the FCC catalyst used in practical use, there will be no major problem. do not have.

The composition of the present invention can be used alone as a catalyst for catalytic cracking of hydrocarbons, and is superior to conventional inorganic oxides in terms of cracking activity, gasoline selectivity, stability against heat and steam, and wear resistance. Demonstrates performance that overwhelms other catalysts.

Furthermore, the composition of the present invention can be used as a matrix for a so-called zeolite catalyst, and even in this case, it exhibits performance that is as good as that of a conventional zeolite catalyst using an inorganic oxide as a matrix.

In the case of IJ fluxed zeolite catalysts using the composition of the present invention, fine zeolites (aluminosilicate)
Kokichi containing 10 to 40% by weight is acceptable.

The present invention will now be described in more detail with reference to Examples, but the catalyst composition for hydrocarbon decomposition according to the present invention is not limited to those prepared in accordance with these Examples.

Example 1 Add pure water 2001 to 25% sulfuric acid 5801 and heat at 30°C.
dilute sulfuric acid was prepared.

To this was added 37001 JIS No. 3 standard water glass solution (SiO□ concentration 85%) at 30°C until the pH reached 4.0.

The mixture was aged for 150 minutes, 15% aqueous ammonia was added until the pH reached 7.6, and the mixture was further aged for 90 minutes.

Next, 25% sulfuric acid was added until pH 13.5, followed by 24%
57'OA of aluminum sulfate solution was added and aged for 30 minutes.

Finally, the pH was adjusted to 7.6 with 15% aqueous ammonia.

A water suspension slurry of Bayer process aluminum hydroxide (Gibsite) with an Al2O3 concentration of 20% is added to a part of this silica-alumina slurry, and the concentration is further adjusted to 3% in advance.
A water suspension slurry of 0% rare earth-exchanged Y-type zeolite was added such that the zeolite content in the final catalyst was 15%.

This gibbsite-zeolite mixed silica-alumina slurry was spray-dried at a hot air temperature of 220°C, washed with a 0.5% ammonia sulfate aqueous solution and 0.5% aqueous ammonia, and dried at 110°C for 16 hours.

Comparative Example 1 Bayer Process A catalyst was prepared in exactly the same manner as in Example 1, except that aluminum hydroxide (gibsite) was not mixed.

Comparative Example 2 Instead of mixing Bayer process aluminum hydroxide (Gibsite), Josier Karion (Grade KC8-
8D) was prepared in exactly the same manner as in Example 1, except that the total solid content in carrion was adjusted to 40% in the final catalyst.

Comparative Example 3 Example except that instead of mixing Bayer process aluminum hydroxide (Gibsite), bentonite (Grade Tone mark) was used so that the total solid content in bentonite was 40% in the final catalyst. The catalyst was prepared in exactly the same way as in 1.

Table 1 shows the abrasion resistance test results and the thermal and steam stability test results for these four types of catalysts.

As can be seen, the catalyst mixed with crystalline alumina of the present invention had better wear resistance and thermal and steam stability than kaolin and bentonite mixed in the same amount in the same synthetic matrix.

Particularly in terms of abrasion resistance, the powdering rate was about 1/2 of that of a catalyst containing a mixture of kaolin and bentonite.

Table 2 shows the results using a laboratory fluidized bed pilot plant.
Decomposition activity was shown using the same raw material oil and under the same measurement conditions.

The catalyst was subjected to the same treatment as in the heat and steam stability test, and then pretreated by calcining at 600°C for 2 hours, and claate-based desulfurized vacuum gas oil was used as the raw material oil.

Decomposition temperature is 490°C, W, HoS, V. is 8hr-1,
The catalyst/raw oil weight ratio was 5.0.

As can be seen, the product of the present invention produces less hydrogen and coke, and has significantly improved gasoline yield and gasoline selectivity.

In particular, the gasoline yield is 3.5 wt% higher than the conventionally widely used catalyst of Comparative Example 1.

Example 2 A JIS No. 3 standard water-glass solution with an SIO2 concentration of 5% was treated with a cation exchange resin to obtain a silicic acid solution with a pH of 2.9 and an SiO2 concentration of 5%.

To this 20 and 9, rare earth-exchanged Y-type zeolite whose concentration had been adjusted to 30% in advance was added so that the amount of zeolite in the final catalyst was 10%.

After adjusting the pH to 7.0 by adding 15% aqueous ammonia, the mixture was homogenized through a homogenizer and spray-dried at a hot air temperature of 220° C. (Catalyst A).

In the same manner as Catalyst A, Bayer process aluminum hydroxide (
Catalyst B was prepared by mixing gibbsite).

Example 3 8102 concentration 11.2% water glass solution 195 to 9
9 was mixed with aluminum hydroxide (bayerite) powder 7.7.

Separately, a 10.5% aluminum sulfate aqueous solution was prepared.

The crystalline alumina-water glass solution and the aluminum sulfate solution were mixed continuously for 10 minutes at a rate of 201/min and 101/min, respectively.

After aging at 65° C. for 3.5 hours, the pH was adjusted to 5.8 with a 11.2 water-glass solution.

This gel was divided into 4 fractions of 9 in 20 fractions, and nothing was added to one of the fractions (catalyst C).

The remaining three were mixed with a rare earth-exchanged Y-type zeolite water suspension slurry whose concentration was previously adjusted to 30% so that the zeolite content in the final catalyst was 5, 10, and 15%, respectively (catalyst R, E, F).

The four catalysts were spray dried, washed and dried as in Example 1.

Example 4 JISB water glass solution 500 with SiO2 concentration 10.5%
1 and a 14.5% alum solution 2501 were prepared.

These two liquids were mixed at a rate of 351/min and 181/min, respectively, for 14 min.
The mixture was mixed continuously for a minute to obtain a silica-alumina slurry with a pH of 3.9.

This 200 K9 was aged at 40° C. for 4 hours and divided into 5 equal parts of 200 K9 each.

Nothing was added to one of them (Catalyst G).

Three of the catalysts were mixed with rare earth-exchanged Y-type zeolite as in the catalysts E and F of Example 3 (catalysts H, I, and J).

To the remaining one, like Catalyst J, zeolite was added so that the zeolite content in the final catalyst was 15%, and then AI! A water suspension slurry of payarite with a 203 concentration of 20% was mixed (Catalyst K).

The four catalysts were spray dried, washed, and dried as in Example 1.

The 11 catalysts of Examples 2, 3, and 4 were subjected to an abrasion resistance test, a thermal and steam stability test, and a pilot plant decomposition test under the same conditions as Example 1.

The various test results are shown in Table 3.

As can be seen from these series of test results, the product of the present invention has excellent wear resistance and high stability against heat and water vapor, regardless of the type of base material (synthetic inorganic oxide). showed high gasoline yield and gasoline selectivity with low hydrogen and coke yields.

In particular, the remarkable improvement in activity seen in catalysts A and B and catalysts J and K clearly shows the effect of mixing the crystalline alumina of the present invention.

Example 5 A silicic acid solution having a pH of 2.9 and an S 102 concentration of 5 was prepared by the method of Example 2.

A water suspension slurry of rare earth-exchanged Y-type zeolite was mixed with this so that the zeolite content in the final catalyst was 5%.

Next, ρ-alumina (
Bayer method aluminum hydroxide (Jibsite) 600
(obtained by airflow calcination at ℃) was mixed.

The catalyst slurry was homogenized through a homogenizer and then spray-dried at a hot air temperature of 220°C.

Crystalline alumina of the catalyst was determined by X-ray diffraction, and a microactivity test was conducted.

The catalyst was subjected to heat and steam treatment at 750° C. for 17 hours in a 100% steam atmosphere, then molded into a 3-diameter x 3-diameter tablet and calcined at 600° C. for 2 hours.

Using claate-based desulfurized vacuum gas oil, the reaction temperature was 492°C.
, W) (S, V, 2.2, reaction time was 5 minutes.

The results are shown in Table-4. From this result, compared to a commercially available catalyst containing the same amount of zeolite, the appropriate amount of crystalline alumina mixed in the final catalyst is 10 to 85%.

Below this range, the activation effect is poor, and above this range, the activity decreases and at the same time the wear resistance becomes unsatisfactory.

Considering the results of each of the above-mentioned Examples, the amount of crystalline alumina is 10 to 85%, preferably 20 to 60%.

Claims (1)

[Scope of Claims] 1 A composition comprising alumina and other inorganic oxides, characterized in that the composition contains 10 to 85% by weight of alumina that can be detected as crystalline by X-ray diffraction method. A catalyst composition for hydrocarbon decomposition. 2. The catalyst composition according to claim 1, wherein said other inorganic oxide is silica-alumina. 3 The matrix is a composition consisting of alumina and other inorganic oxides, in which 10 to 85% by weight of alumina, which can be detected as a crystalline substance by X-ray diffraction, is used as a matrix. A catalyst composition for hydrocarbon decomposition characterized by containing the following.