DE1207351B - Process for the preparation of a silica-alumina petroleum cracking catalyst - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. α .:

BOIj

German KL: 12 g -

Number: 1207351

File number: G 32860IV a / 12 g

Filing date: August 3, 1961

Opening day: December 23, 1965

The use of mixed silica-alumina gels as a cracking catalyst for petroleum has long been known, and it is also common to stretch such catalysts by adding clay. The usual manufacturing procedure Such mixed gels consists in using a silicate solution to precipitate the silica hydrogel acidify, add an aluminum salt to the hydrogel and finally aluminum oxide with a base precipitate out of the mix. While this process results in a useful catalyst, it does it is an expensive process because of the large quantities of acid used to precipitate and generate the silica of aluminum oxide, large amounts of an alkaline precipitant are required. The known procedure is described in detail in U.S. Patent 2,363,231, for example. After that, that will Silicic acid hydrogel by combining equal amounts of a sodium silicate solution with a Acid produced, whereupon the aluminum oxide is then incorporated into the hydrogel. One The method described for incorporating the aluminum oxide into the hydrogel is to use aluminum sulfate to combine with ammonium hydroxide to

Process for the preparation of a silica-alumina petroleum cracking catalyst

Applicant:

W. R. Grace & Co., New York, N.Y. (V. St. A.)

Representative:

Dr. rer. nat. J.-D. Mr. v. Uexküll, patent attorney,

Hamburg-Hochkamp, Königgrätzstr.

Named inventor: Charles P. Wilson Jr., Cincinnati, Ohio; Frank G. Ciapetta, Silver Spring, Md .; John B. Jones, Baltimore, Md. (V. St. A.)

Claimed priority: V. St. v. America August 17, 1960 (50056.50 067)

greatly reduced from the aluminum sulfate solutions; Another advantage of the method is that a To precipitate a large part of the otherwise required amount of acid in aluminum oxide hydrate, which is saved.

then subsequently added to the silica hydrogel. According to the invention, a process for the preparation is provided. In this process, a silica-alumina-petroleum cracking catalytic acid is further sulfurized for the production of aluminum sulfate by gelling an alkali silicate solution with needs, and in addition is one of the aluminum sulfuric acid and adding aluminum sulfate to it oxide content in the end product corresponding amount 30 to the silica hydrogel obtained, then Ammonium hydroxide required. On the other hand, the alumina can be precipitated by adding one from a table in the listed USA.-patent-basic precipitant and incorporation of up to writing out that a silica hydrogel and 50% clay, especially kaolin, suggested which Crack produced by dried aluminum hydroxide is characterized in that one uses the aluminum catalyst is far less effective than one in which sulfate is added as a slurry, which incidentally as described, contains aluminum hydroxide which has not yet been converted from silicic acid, hydrogel and aluminum oxide consisting of a catalyst, the molar ratio of sulfate to aluminum. oxide in the slurry less than 3: 1, min-

It has now been found that a highly effective but 1.5: 1 is at least, and that the amount of Petroleum cracking catalyst selected from silica hydrogel together 40 slurry so that a product with a Men with aluminum oxide and aluminum hydroxide Aluminum oxide content of up to 50% (excluding can be produced. With this method, the aluminum oxide content of the clay component) therefore, an effective catalyst with an extremely high level is obtained. Gelling is preferred at high aluminum oxide content of up to 50% (carried out from a temperature below 74 ° C, and and finally of the aluminum oxide, which becomes the silicic acid hydrogel formed above it before going out may still be contained in the clay) obtained treatment preferably up to 2 hours will. The use of aluminum hydroxide aged long. The inventive method can in the preparation of the catalyst is because of the also carried out in such a way that the MoI-with it associated cost and labor savings of the ratio of sulfate to aluminum oxide in the mixture of great importance: On the one hand, this increases the consumption by adding aluminum hydroxide to the alkali expensive alkaline compounds such as amsilicate solution before gelling with sulfuric acid moniak or soda to precipitate the aluminum oxide below 3: 1.

509 759/545

3 4

The aluminum oxide is therefore added to the particle size in the system and that of the starting

the molar ratio of SO ₄ : Al ₂ O _{3 is} reduced to below 3: 1. If the shape or nature of the

squeeze. When using a molar ratio of hydrate is such that during processing of the

from SO ₄ : Al ₂ O ₃ of 1.5: 1 is only half as much sulfur catalyst a size reduction then occurs

acid required as for normal aluminum sulfate 5, the particle size of the starting hydrate can be larger

with a molar ratio of SO ₄ : Al ₂ O ₃ of 3: 1. provided that they are during editing

For economic reasons, the gelling rate is reduced to the above distribution.

Silicate solution preferably used sulfuric acid. The activity of the hydrate is determined by the

There can be several ways of producing surface area and pore volume according to a

of the aluminum oxide-containing slurries with heat treatment for 10 hours at 538 ° C

a reduced SO ₄ : Al ₂ O ₃ molar ratio (nitrogen adsorption method according to the BET method).

be used. The minimum values for the surface and for the

For one, aluminum hydroxide is directly with pore volume is preferably 100m ² / g or

less sulfuric acid is converted than it is necessary to achieve 0.15 cm ³ / g.

of the 3: 1 molar ratio of normal aluminum 15 The used in the process according to the invention

sulfate A1 ₂ (SO ₄ ) _{3 is} necessary. The hydroxide can be the clay is preferably a raw kaolin clay, which

to be added to the dilute sulfuric acid; can be used as it arises and little

or one can concentrate with equal success or require no pretreatment at all. A typical one

Sulfuric acid to an aqueous slurry of the composition of a suitable clay is as follows:

Add aluminum hydroxide. In both cases 20 τ ν κ ■ äi η 0 / as λ

the temperature, dilution, and exposure to it are ^calculated

precisely controlled in time to achieve the desired conversions SiO ₂ , / "53.4

to achieve and a lump formation or solidification,% 0.22

to avoid. Na ₂ O,% 0.041

Or aluminum hydroxide becomes with as much sulfur 25 TiO ₂ ,% 1> 77

acid converted that the SO ₄ : Al ₂ O ₃ molar ratio V ₂ O ₅ ,% 0.037

of normal aluminum sulphate with a value of total volatile substances

3.0: 1.0 is made, whereupon after, before or at 955 ° C,% 14.4

Implemented conversion of aluminum hydroxide to average particle size, μ .. 1.5

is set to the desired reduction in the _30th

To achieve molar ratio. The particle size is unimportant when considering the structure

And finally, a normal aluminum tone can be so soft that a coarse material during sulfate solution with a 3.0: 1.0 molar ratio breaks down and disperses easily during processing, However, there will be enough aluminum. Raw kaolin clay is relatively cheap, and its hydroxyd to the dilute sodium silicate solution before 35 use in combination with a synthetic the gelation by sulfuric acid added to the silica-alumina component gives a desirable host To produce molar ratio, whereupon economic advantage, since relatively large tonal norms Aluminum sulfate to the aluminum hydroxide amounts up to 50% of the catalyst with a synthetic one Silica gel is given. table silica-alumina component combined

It has been found that all of the aluminum can be 40 without affecting the quality of the final product.

oxide is catalytically active, regardless of whether it is significantly worsened,

it is made from normal aluminum sulphate or from the It can be taken in various ways,

Hydroxide or a combination of these two to the synthetic prepared as described above

comes from; it is therefore called an active clay component with up to 50% of a kaolin-like component

and is part of the synthetic catalyst 45 clays to be added. Preferred is the tone to that

component in contrast to the inert aluminum - dilute sodium silicate solution before gelation

oxide, which is contained in the clay. Sulfuric acid added. However, you can change the tone

The commercially available aluminum oxide trihydrates (aluminum also in any process step before derminium hydroxide) vary in their physical add those step in which the mixed and chemical properties are considerable, but 50 components-containing slurry is too microd the present invention is not spray-dried on a specific spherical structure .
Variety or a certain degree of purity. A typical procedure is briefly summarized. It is desirable that the iron and sodium be as follows: Concentrated sodium silicate with an extremely low content; with a good aluminum content of 28.5 percent by weight SiO ₂ , 8.65 percent by weight oxide hydrate, for example, there was an iron content of 55 percent Na ₂ O and 62.85 percent by weight water 0.005% and an Na ₂ O content of 0.3%. This is done with water on a SiO _? -Content of 3 to limits are not necessary, however. Coarse particles 8% by weight and preferably 4 to 6% by weight are better avoided as they do not dilute well at the%. Preferably, the desired system is allowed to disperse and undesirably affect the appearance of the amount of kaolin clay prior to gelation by the sulfur end product; in the case of her acid added to the dilute sodium silicate solution, the catalyst is in microspheroidal form. If the clay is not gelled into the coarse particles a strong wear of the sieves sodium silicate, but at one and nozzles of the spray dryer and clog them. Later process stage before spray drying Preferably, the particle size distribution is added for 65, so the abrasion or the attrition of this process suitable aluminum oxide hydrates of the finished catalyst is adversely affected, which is calculated so that at most 10% greater than 74 μ. and an uneconomical reduction in the clay content is at least 95% smaller than 44 μ. This affects requires in the finished catalyst.

5 6

The type of gelation of the dilute sodium- To determine the catalytic cracking activity,

silicate clay slurry (or the silicate solution of the selectivity and especially the stability of the

If clay is added later, tests may have been carried out on various products, in which the

Be carried out by exposing each product to high temperatures, dear ones, known in the acidic or alkaline range 5 Such conditions often prevail in technical

Working processes are used, as is also the case with the Hanseatic application of the catalytic converters and can

The usual production of cracking catalysts lead to deactivation of the catalyst. the

is common. Catalysts were therefore deliberately both

In the case of the two-stage thermal deactivation used in the examples, as well as one Acid addition, the gelation was subjected to steam deactivation in the first stage, whereupon subsequently

reached at a pH of about 10.0, in which their cracking activity was determined,

about 70% of the total Na ₂ O content of the sodium. For steam deactivation, the fresh one

silicate solution were neutralized. Catalyst pressed into beads, 5 hours with

The acid addition of the second stage is ^{heated to any steam at 204 0} C, then 3 hours and can be omitted or used to treat the 15 without steam at 565 ⁰ C and finally pH of the hydrogel to any 24 hours in one Steam atmosphere of 4.2 kg / cm ^a desired value on the acidic or alkaline and 565 ° C treated. Set to 7.0 on the steam side. In the examples, the deactivation cracking activity was determined, about 90% Na ₂ O of the silicate after the second acid by adding 200 ml of the deactivated catalyst is neutralized to an addition and a silica were contacted with 20 reactor which geeinem to 454 ⁰ C pH Received value of 7.0. When the acid was hold. A total of 238 ml of light addition was omitted in the second process stage, so East Texas gas oil with a boiling range from 260 to 371 ° C is above the catalyst pressed into spheres for the precipitation of soluble aluminum oxide in the with _{a boiling range from 260 to the Na 3 O remaining in the sodium silicate} a rate of 120 ml per hour of aluminum oxide-containing slurry, which leads to a throughput rate of 0.6 ml, which corresponds to the amount of oil added from the outside per milliliter of catalyst per hour, and leads to complete precipitation of the aluminum die Reaction products were isolated and the basic precipitant required for the basic precipitating agent in the catalyst was reduced. certainly. The isolated liquid reaction products

The gelation can be subjected to a distillation test at any temperature up to 3 ° and the

74 ^° C., and the silica gel can be determined for each corresponding d + l activity. The above

Temperature up to 74 ° C, for example up to 2 hours 204 ° C distilling fraction and also the destill

to be aged. Breastfeeding losses were determined and taken together as

After the silica gel-clay mixture (or D + L called.

the silica gel without clay) has been prepared, 35 which is used as a gas generating factor and as carbon an alumina-containing slurry in values designated production factor are the more reliable Amount added to the desired tive gas and carbon amounts, which with the Aluminum oxide content in the synthetic composite catalyst according to the invention in comparison with to give nente of the finished catalyst. After a standard catalyst with the same activity the Silica gel-clay slurry was created intimately with the 40 area.

A similar cracking process was used to make the alumina slurry

if a suitable alkali such as ammonia is added, the cracking activity of the catalysts after a thermal

to complete the precipitation of aluminum oxide to determine deactivation at 843 ° C,

permanent. The slurries thus processed In this case, no steam was used, and the

are then filtered and the desired synthetic 45 deactivation was determined before the D + L activity

and clay-containing components as filter cake vity by heating the catalyst for 5 hours

won. 204 ° C and another 3 hours at 538 ⁰ C and finally

The filter cake can be carried out with as little water as possible for three more hours at 843 ° C., reslurried, so that a viscous, but pumpable slurry is obtained in the following examples, which is explained in more detail at 5 ° and is suitable for spray drying. The dried τι · · 1 1 product can then in turn be slurried with water, in general with dilute ammonium sulfate solution, in one with a stirrer and a circulation for washing. In connection with the pump-equipped container, 56.71 were washed. The product is rinsed with water-diluted sodium silicate solution with an Na ₂ O content, which has a low sodium content. In the connection of 14.7 g / l and an SiO ₂ content of 48.5 g / l, the washed catalyst is filled through. The temperature was adjusted to 46 ° C, any method, e.g. B. by vacuum drying whereupon 2.95 kg kaolin clay (2.5 kg dry basis) or evaporative drying, finally dried. were given. In the table given below, the 60 circulations for 10 minutes in the sodium silicate are chemically and physically underserved by stirring the clay. Then been performed by investigations in the course, which were in the products ER- 5 minutes 1800 ml of 39% sulfuric acid i§ ^e hold. The gelation occurred 3 minutes after the addition of the surface and the pore volume were with total acid at a pH of 10.3. The nitrogen adsorption method according to Brunauer-65 was stirred for a further 30 minutes, whereupon 535 ml Emmett-Teller (J. Am. Chem. Soc, 60, p. 309 39% sulfuric acid were added. The pH value [1938]) was carried out after the 3 hour product of the resulting slurry was 7.1. The Aufauf-538 ⁰ C had been heated. slurry was aged for 2 hours at 46 ° C,

whereupon an alumina-containing slurry prepared as follows was added:

Sulfuric acid was reacted with aluminum hydroxide to form an aluminum sulfate _{solution with an SO 4} : Al ₂ O ₃ molar ratio of about 3: 1, with excess sulfuric acid also being added to ensure a more rapid and complete reaction with the aluminum hydroxide. After adding water, the solution contained 95 g / l Al ₂ O ₃ and 12 g / l excess sulfuric acid. 725 g of aluminum hydroxide, an amount equivalent to the aluminum oxide content of the aluminum sulfate solution, were added to 4950 ml of this solution.

The mixed slurries had a pH of 3.6. Then a total of 2100 ml Ammonia solution of 26 ° Baume was added, whereupon the pH rose to 6.0. The synthetic The mass of silica-alumina and clay was filtered off. 6.8 kg of the filter cake were added slurried again with 21 water and spray-dried. The pH of the spray dried product was 4.5. The spray-dried product was with an ammonium sulfate solution of 4 ° Baumo washed at 54 ° C and a pH of 4.7 and then with deionized water at 54 ° C and a pH of 9.5 and the washed product dried at 149 ° C.

Example 2

_{56.71 of dilute sodium silicate solution with an Na 2} O content of 14.7 g / l and an SiO ₂ content of 48.5 g / l were placed in a container equipped with a stirrer and circulating pump. The temperature was raised from the outside to 40.5 ° C. by means of a hot water jacket, whereupon 2.95 kg (2.5 kg dry basis) kaolin clay were added. 725 g of aluminum hydroxide were added to the dilute sodium silicate solution. It was mixed for 15 minutes and 39 ° ml / added in a period of 4 minutes in 1800 _o sulfuric acid. The mass gelled 6 minutes after the addition of sulfuric acid. Mixing was continued for 10 minutes at which time the pH was 9.7. 585 ml of 39% sulfuric acid was added to adjust the pH to 7.0. The mixture was aged for 1 hour at 41 ° C. and then 4950 ml of aluminum sulfate _{solution with an Al 2} O ₃ content of 93 g / l and 12 g / l of sulfuric acid in excess were added to the Al ₂ O ₃ . The obtained slurry having a pH of 3.3 was mixed for 15 minutes, after which 3100 ml of 15% ammonia solution was added to adjust the pH to 5.8. The slurry was heated to 57 ° C. and then filtered, the synthetic silica-alumina component being recovered as a filter cake together with the clay component. 6.8 kg of filter cake was reslurried with 1 liter of water to form a viscous but pumpable slurry which was then spray dried.

The spray dried product was reslurried with deionized water to give a slurry with a pH of 5.4. The slurry was filtered and washed five times with an ammonium sulfate solution having a pH of 9.0 and 2 ° Baume and a temperature of 54 ° C and washed five times at 54 ° C with deionized water which was adjusted with ammonia so that a Slurry with a pH of 9.0 was obtained. The solids were dried at 149 ⁰ C.

example

II

Kaolin in the mixed catalyst,%

Synthetic component in the mixed catalyst,%

Al ₂ O ₃ in the synthetic component,%

Hydrate in the synthetic component,%

Type of kaolin addition

Type of aluminum hydroxide addition

Chemical analysis of the mixed catalyst,%

Al ₂ O ₃

Na ₂ O

SO ₁

Fe

Physical properties after heating for 3 hours at 538 ° C

Surface area, m ² / g

Pore volume, cm ³ / g

Cracking activity and selectivity

1. Activity after steam treatment, D -f- L

Gas generation factor

Carbon production factor

2. activity after heating (3 hours at 843 ° C),

thermal D + L values

Gas generation factor (standard catalyst is

equal 1)

Carbon generation factor (standard catalyst is equal to 1)

40

40

60
25th
50
to the silicate
to normal
Aluminum sulfate 60
25th
50
to the silicate
to the silicate 32.73
0.06
0.0
0.15 34.71
0.05
0.0
0.14 271
0.55 317
0.48 26.0
1.15
0.91 26.8
1.29
1.13 40.6 40.3 1.12 1.11 0.98 0.88

Claims (4)

Patent claims: 1. Process for the preparation of a silica-alumina petroleum cracking catalyst by gelling an alkali silicate solution with sulfuric acid and adding aluminum sulfate to the obtained one Silicic acid hydrogel, subsequent precipitation of the aluminum oxide by adding a basic one Precipitant and incorporation of up to 50% clay, especially kaolin, characterized in that that the aluminum sulfate is added as a slurry, which by the way Contains unreacted aluminum hydroxide, the molar ratio of sulfate to aluminum oxide in the slurry is less than 3: 1, but at least 1.5: 1, and that the Amount of slurry chosen so that a final product with an alumina content of up to 50% (excluding the aluminum oxide content of the clay component) is obtained. 2. The method according to claim 1, characterized in that the molar ratio of sulfate ίο to aluminum oxide in a mixture by adding aluminum hydroxide to the alkali silicate solution reduced to below 3: 1 with sulfuric acid before gelling. 3. The method according to claim 1 and 2, characterized in that the gelling at a Temperature below 74 ° C performs. 4. The method according to claim 1 to 3, characterized in that the formed silica hydrogel Aging for up to 2 hours before continuing treatment. Considered publications:
German Auslegeschrift No. 1110 351;
German patent applications ST 1953 IVd / 23b (published on 8 July 1954), U 432 IVd / 23b (published on 26 3.1953); U.S. Patent Nos. 1,840,450, 2,487,065, 763,622, 2,374,313, 2,363,231;
British Patent No. 799,757; "Petroleum Refiner", 1959 (September), pp. 169-174.