NL8203099A - METHOD FOR PREPARING CATALYST MATERIALS, AND CATALYST MATERIALS OBTAINED BY THIS METHOD - Google Patents

Description

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Process for the preparation of catalyst materials, as well as catalyst materials obtained by this process.

The invention relates to the preparation or manufacture of catalysts and more particularly to the production of hard wear-resistant zeolite-containing catalysts which have a high activity for the catalytic conversion of hydrocarbons.

Hydrocarbon conversion catalysts, such as fluid cracking catalysts (FCC), which comprise crystalline zeolites dispersed in an inorganic oxide matrix, are usually obtained by spray drying an aqueous suspension of zeolite, clay, and a suitable binder such as silica, alumina, silica, or alumina . The spray dried catalyst particles can be calcined and ion-exchanged to remove unwanted alkali metal impurities.

Canadian Patent 967,136 describes a hydrocarbon conversion catalyst comprising zeolite, clay and an alumina binder. The catalysts are obtained by spray drying a mixture of up to a low sodium ion-exchanged zeolite, clay and alumina (chlorohydrol) and calcining the spray dried particles to obtain hard, wear-resistant catalysts.

US Pat. No. 3,425,956 discloses a process for the preparation of a zeolite-containing cracking catalyst in which a spray-dried partial ion-exchanged zeolite and silica-alumina hydrogel eosposite is calcined and then ion-exchanged. The calcination step stabilizes the zeolite and improves the removal of alkali metal oxide.

8203099, - 2 - <¥

In recent years, the cracking catalyst industry has particularly focused on producing catalysts which are highly abrasion resistant, active and selective for the production of gasoline fractions.

Therefore, an object of the present invention is to provide a method by which highly active, wear-resistant catalysts can be produced economically.

Another object is to provide a process for the preparation of zeolitic hydrocarbon conversion catalyst that does not require calcination at high temperature multiple times.

Yet another object is to provide thermally stable catalytic cracking catalysts capable of producing a high level of gasoline fractions.

* A still further object is to provide zeolite-containing fluid cracking catalysts which are selective for the preparation of high octane gasoline fractions. These and other objects of the present invention will become apparent to those skilled in the art from the detailed description below and the drawing showing a block diagram representing a method incorporating the present invention.

Generally speaking, the present invention amounts to a process for the production of catalysts containing alumina-bound zeolite, wherein a dried particulate composite comprising an alkali metal containing zeolite and an aluminum chlorohydrol binder is calcined and then subjected ion exchange to reduce its alkali metal content to less than about 1% by weight.

More particularly, Applicant has found that by calcining an aluminum chlorohydrol-bound particulate catalyst composite comprising an alkali metal-containing zeolite, the catalyst composite can be cured simultaneously by converting the aluminum chlorohydrol into alumina. binder and activated for the removal of sodium by subsequent ion exchange.

A clearer understanding of the invention can be obtained with reference to the drawing, which shows a catalyst preparation process which can be used in the practice of the present invention.

As shown in the drawing, sources of aluminum chlorohydrol solution, zeolite slurry and clay slurry are combined in a blender to obtain an even aqueous slurry. As indicated in the figure, the mixed chlorhydrol / zeolite / clay slurry is passed to a spray drying step in which the slurry is converted into particulate solid composites comprising zeolite and clay particles bonded by aluminum chlorhydrol. These composites are fired to obtain hard, wear-resistant particles. During the firing step, the aluminum chlorohydrol is converted into a strong alumina binder and acid chloride by-products, which are removed from the composite. The firing step also makes the alkali metal oxide present in the zeolite component more accessible for removal by the subsequent ion exchange.

As shown in the drawing, the fired catalyst composite is ion-exchanged and / or washed to remove excess alkali metal oxide and any other soluble impurities that may be present. The ion exchange step can be performed using an ammonium salt solution, such as ammonium sulfate and / or rare earth chloride solution. The ion-exchanged composite is washed with water to remove soluble impurities.

After the ion exchange and washing, the catalyst becomes composite, which is less than about 1% at this point, at 8203099

t P

Preferably contains less than 0.5 wt% alkali metal oxide, dried to a level of about 5 to 25 wt% moisture.

The aluminum chlorhydrol solution used in the practice of the present invention is readily available from commercial sources and usually has the formula Al2 + m (OH) Cl2, wherein m has a value of about 4 to 12.

The aluminum chlorhydrol solutions are also often referred to in the literature as polymeric cationic hydroxyaluminum complexes or aluminum chlorohydroxides, the polymers being formed from a monomeric precursor of the general formula (0 ^ 01.2 ^ 0. In the present application, the binder component will be indicated as aluminum chlorhydrol The preparation of the aluminum chlorhydrol solution is typically described in U.S. Patent 2,196,016, Canadian Patent 967,136 and U.S. Patent 4,176,090 Typically, the preparation of aluminum chlorhydrol involves the use of aluminum metal and hydrochloric acid react in amounts which will give rise to a material of the formula indicated hereinbefore. The aluminum chlorhydrol can be obtained using various sources of aluminum, such as aluminum oxide (A 2 O 3), clay and / or mixtures of aluminum oxide and / or clay with aluminum metal Preferably, the aqueous aluminum chlorohydrol solutions used in the practice of the present invention will have a solids content of about 15 to 30 wt% A 2 O 2.

The zeolite component used in the present invention is typically a synthetic fauja-30 site zeolite such as sodium type Y zeolite (NaY) which contains about 10 to 15 wt% Na 2 O. It is also possible to subject the zeolites to partial ion exchange to lower their sodium content prior to incorporation into the catalyst. Typically, the zeolite-35 component may comprise a partially ammonium-exchanged type Y (NH ^ NaY) zeolite, which is about 3 to 4% by weight * 8203099 - 5 - Λ *%

Will contain £ 0. Furthermore, the zeolite can be partially exchanged with polyvalent metal ions, such as rare earth metal ions, calcium and magnesium. The zeolite component can also be exchanged with a combination of metal and ammonium 5 and / or acid ions. Also, the zeolite component may include a mixture of zeolites such as synthetic faujasite in combination with mordenite and the ZSM type zeolites.

Preferably, the zeolite is combined with the aluminum chlorohydrol and a clay component in the form of an aqueous suspension containing about 20 to 60 weight percent solids.

The catalysts of the invention can contain substantial amounts of clay, such as kaolin.

However, the clay component is optional and comprises about 0 to about 80% by weight (dry basis) of the total catalyst material. Although kaolin is the preferred clay component, it is also possible to include thermally modified kaolin, such as metakaolin, in the catalyst material.

During the mixing step, as shown in the drawing, a feed slurry feed slurry 20 is obtained which contains about 20 to 60% by weight solids, of which about 5 to 25% by weight consists of aluminum chlorohydrol (dry basis) as A ^ 0 ^, 0 to 60% by weight from zeolite and about 0 to 90% by weight from clay. Although the drawing shows a method by which fluid cracking catalysts are obtained by spray-drying the catalyst preparation slurry, it is also possible to obtain particulate catalysts of a larger particle size, ie of the order of about 1 to 2 mm, by the formation of beads or pellets of the present materials which are particularly useful for the production of catalysts for hydrogenation processes, such as hydrocracking, hydrodesulfurization and hydrogenating nitrogen, and demetallization catalysts.

The spray drying step is performed using inlet temperatures in the range of about 300 to 400 ° C and outlet temperatures of about 100 to 8203099-6-200 ° C. During the spray drying step, the moisture content of the particles is reduced to about 10 to 30% by weight. Catalyst composites have a particle size on the order of 20 to 150 microns.

After spray drying, the catalyst composites are fired at temperatures on the order of about 300 to 700 ° C for a period of about 5 to 3 hours, and preferably about 1-2 hours. During the firing step, the aluminum chlorhydrol is converted into solid aluminum binder and volatile acid chlorides, which are removed from the firing zone as part of the waste gas stream. Removal of the acid chlorides at high temperatures converts the aluminum chlorhydrol into an alumina binder, producing a strong, wear-resistant catalyst particle.

Furthermore, the firing step results in activation, ie, detachment, of the residual alkali metal oxide contained in the zeolite component and which is easily removed by subsequent ion exchange and / or wash steps.

The ion exchange step, which reduces the alkali metal oxide level of the catalyst composites to less than about 1% by weight, is conducted using water and / or aqueous ammonium salt solutions such as ammonium sulfate solution and / or polyvalent metal solutions such as rare earth chloride solutions . Typically, these ion exchange solutions contain about 1 to 10% by weight of dissolved salts. It is often found that multiple exchanges are beneficial to achieve the desired degree of alkali metal oxide removal. Usually, the exchanges are performed at temperatures on the order of 50 to 100 ° C. After the ion exchange, the catalyst components are washed, usually with water, to lower the level of soluble impurities to a desirable level.

After the ion exchange and washing, the catalyst composites are dried, usually at temperatures ranging from about 100 to 200 ° C, to reduce their moisture content to a level of preferably less than about 8203099 '5 - 7 - spring 15 wt%.

Cracking catalysts obtained by the process of the invention are very active for catalytic cracking of hydrocarbons. It has typically been found that the activity of these catalysts ranges from about 60 to 90 vol% conversion after deactivation and elevated temperatures. Furthermore, it has been found that the catalysts are very selective for the production of gasoline and in particular for the production of cracked gasoline fractions with a high octane number. Furthermore, the catalysts are extremely strong and durable.

While the major components of the catalysts include zeolite, aluminum chlorhydrol and optionally clay, other components, such as particulate alumina and rare earth-impregnated alumina, may be added to improve the ability of the catalyst to control SO.

Furthermore, it goes without saying that the catalyst can be combined with small amounts (1 to 100 ppm) of platinum and palladium, which are added to improve the CO oxidation characteristics of the catalyst. The wear properties of the catalyst are expressed in terms of the Davison Index (DI) and the Jersey Index (JI) as determined in U.S. Patent No. 4,247,420.

Having described the basic aspects of the present invention, the following examples are presented to illustrate specific embodiments thereof. Example I

The following ingredients are combined in a 37.85 liter stainless steel mixing kettle: 3404 g of aluminum chlorhydrol solution of the formula A (CICOH) 4 and containing 23.5% by weight; 7500 g (dry basis) kaolin; 1500 g (dry basis) fired rare earth 35 exchanged type Y zeolite (CREY); and enough water to obtain a suspension containing 25 wt% solid.

8203099 - 8 -

The type Y fired rare earth exchanged zeolite was obtained by exchange with aqueous mixed rare earth chloride solution at pH 5 of NaY, followed by firing at 538 ° C for 3 hours and containing 15.02 wt% 5 ^ 2 ^ 3 and ^> 8 Na ^ O. The suspension was stirred well and spray dried using a gas inlet temperature of 320 ° C and a gas outlet temperature of 150 ° C. The spray dried catalyst particles containing about 25 wt% water and 0.5 wt% 10 ^ were fired (ie heated) in a muffle oven at a temperature of 538 ° C for 1 hour. After firing, the catalyst was dried at a temperature of 150 ° C. The chemical analysis of this catalyst as well as its cracking properties are shown in Table A.

Example II

The preparation method of Example I was repeated. However, 3000 g of the fired catalyst particles were ion-exchanged by contact with 9000 ml of ammonium sulfate solution containing 3% by weight of ammonium sulfate. The analysis and properties of this catalyst are shown in Table A.

Example III

The preparation method of Example I was repeated. However, the zeolite consisted of an ammonium-exchanged fired type Y zeolite containing 12.5 wt% ZA2O2 and 0.5 wt%. The catalyst was not ion-exchanged after firing. The properties of this catalyst sample are shown in Table A.

Example IV

The preparation procedure of Example I was repeated. However, an uncooked rare earth exchanged zeolite Y (ZAY) was used containing 13.4 wt% ZA2O2 and 3.2 wt% Na2O. This catalyst sample was not ion-exchanged after firing. The properties of this catalyst are shown in 8203099-9 - Table A.

Example V

The catalyst preparation method of Example IV was repeated. However, 3000 g of the fired catalyst 5 is exchanged with 9000 ml of ammonium sulfate solution

containing 3% by weight of ammonium sulfate after firing. The properties of this catalyst are shown in Table A. Example VI

The catalyst preparation method of Example 10 I was repeated. However, the finished catalyst contained 25% by weight of the sodium ammonium zeolite Y containing 3.8% by weight Na 2 O which was obtained by exchanging a sodium zeolite Y with ammonium sulfate. 3000 g of this catalyst were washed with 9000 ml of water after firing. The properties of this catalyst are shown in Table B.

Example VII

The catalyst preparation procedure of Example VI was repeated. However, after firing, 3000 g of the catalyst was exchanged with 9000 ml of ammonium sulfate solution containing 3 wt% ammonium sulfate. The properties of these catalysts are described in Table B.

Example VIII

The catalyst preparation method of Example I was repeated. However, the zeolite comprised 25% by weight of an ammonium-exchanged fired stabilized type Y zeolite (Zl4US zeolite) obtained by the method of U.S. Patent 3,449,070. The Z14US zeolite contained about 3.8 wt% Na2O at the time of incorporation into the catalyst. 3000 g of the catalyst was exchanged after firing with 9000 ml of ammonium sulfate solution. The properties of this catalyst are shown in Table B.

Example IX

The catalyst preparation method of Example I was followed. However, a catalyst was prepared containing 8203099-10-40 wt% ammonium-exchanged type Y zeolite containing zeolite 3.8 wt% Na 2 0. Furthermore, the amount of chlorohydrol was tuned to provide an alumina binder content of 15 wt% and the kaolin content was tuned to 45 wt%. This catalyst was not washed after firing. The properties of the catalyst are shown in Table C.

Example X.

The catalyst preparation method of Example IX was repeated. However, after firing, 3000 g of the catalyst was washed with 9000 ml of water. The properties of this catalyst are shown in Table C,

Example XI

The catalyst preparation method of Example IX was repeated. After firing, however, 3000 g of the catalyst was washed with 9000 ml of ammonium sulfate solution containing 3% by weight of ammonium sulfate. The properties of this catalyst are shown in Tables C and D.

Example XII

20 A commercial comparison catalyst

containing 40 wt% Z14US zeolite, 23 wt% of a silica sol binder and 37 wt% kaolin clay was prepared by the method described in U.S. Patent 3,957,689. This catalyst was washed with ammonium sulfate and its properties are described in Table D. Example XIII

A catalyst was prepared by the method shown in Example IX. However, the zeolite component comprised 40 wt.% Of a Z14US type zeolite exchanged with ammonium sulfate to a level of about 0.2 wt.%. This catalyst was not ion-exchanged or washed after firing. The properties of this catalyst are shown in Table D.

Example XIV

In this example, the properties of the catalysts prepared in Examples I to V were determined and 8203099 2 - η - tabulated in Table A below.

Table A

Catalyst of

Example I II III IV V

5 Analyzes

Wt% Na 2 O 0.51 0.14 0.18 0.44 0.18

Wt% RE203 2.26 2.33 2.43 2.77 2.74

Wt% SO ^ 0.18 1.31 0.15 0.13 0.67

Specific surface area (m / g) 133 133 148 148 146

Density (g / cm2) 0.84 0.84 0.84 0.87 0.87

Davison Index /

Jersey Index 6 / 0.8 36 / 3.5 3 / 0.1 3 / 0.9 16 / 1.7 15 Microactivity (vol.% Conversion)

Deactivation (s-732) (1) 72 73 71 76 76

Deactivation 20 (816) (2) 54 68 65 62 72 (1) s-732 3 hours at 538 ° C in air, followed by 8 hours at 732 ° C in 100% steam at 104 kPa gauge 25 (2) 816 5 hours at 816 ° C in 100% steam at 0 kPa gauge pressure.

From the data shown in Table A, it can be deduced that the activity of catalysts containing the non-fired Y zeolite (Examples IV and V) is superior to those containing the pre-fired zeolite (Examples I, II and III).

Example XV

In this example, the properties of the catalysts prepared in Examples VI, VII and VIII were determined and compared in Table B below.

8203099

- 12 -Table B

Catalyst of

example VI VII VIII

Wt% Na 2 O 0.58 0.13 0.27 5 Unit cell (nm) 2.462 2.462 2.450

Microactivity (vol.% Conversion after S-732 deactivation) 60 59 57

Data from the test unit 10 Microactivity (vol.% Conversion) after S-827 deactivation (3) 58.5 62.0 60.5

Research Octane Number 89.5 90.3 90.6

Engine Octane Number 78.2 79.0 79.3 (3) S-827: 18 hours at 827 ° C, 20% steam, 80% air, 20 kPa gauge pressure.

From the data shown in Table B, it can be deduced that the octane selectivity for the catalysts prepared in accordance with the present invention (Examples VI and VII) is almost equal to that of the catalyst containing the Type Y-fired Z14US zeolite (example VIII).

Example XVI

In this example, the properties of the catalysts obtained in Examples IX, X and XI are compared, as shown in Table C below.

Table C

Catalyst

of Example IX X XI

35 No washing / scrubbing Exchange exchange with water with ammonium sulfate

Wt% Na 2 O 2.11 0.91 0.54

Microactivity 40 after S-732 deactivation 16 50 67 suspension 8203099 - 13 -

From the above data, it can be seen that substantial removal of sodium can be achieved by using the present invention even when using only water (Example X) instead of ammonium sulfate solution (Example XI).

Example XVII

The properties of the catalysts described in Examples α XI, XII and XIII are compared and summarized in Table D below.

10 Tabal D

Catalyst of

example XI XII XIII

Wt% Na 2 O 0.22 0.54 0.04

Microactivity after 15 S-732 deactivation 69 67 69

Microactivity (vol% conversion) after 760 deactivation (4) 55.0 68.0 71.0

Research-0 ctane-number 92.8 92.7 93.0

Engine Octane Number 81.3 80.2 81.8 x USY exchanged to 0.20% Na 2 O (4) 760: 16 hours at 538 ° C in air followed by 16 hours at 760 ° C, 100% stora, 0 kPa gauge pressure.

The above data demonstrate that the use of the process of the invention (Examples XI and XIII) provides catalysts of high activity and good octane selectivity compared to a prior art catalyst (Example XII).

8203099

Claims (12)

Process for producing catalyst materials, characterized in that an (5) an aqueous mixture of an alkali metal containing zeolite and aluminum chlorhydrol is prepared; (b) form this mixture to obtain particulate zeolite / aluminum chlorohydrol composites containing more than about 1% by weight alkali metal oxide; (C) firing these composites at a temperature greater than about 500 ° C; and (d) subjecting the fired composites to ion exchange and washing to obtain catalyst particles having an alkali metal oxide content of less than about 0.5% by weight. Process according to claim 1, characterized in that the aluminum chlorhydrol has the formula Al2 + m (OH) 3m Clg, wherein m has a value of about 4 to 12. Method according to claim 1, characterized in that the zeolite is a type Y zeolite. A method according to claim 1, characterized in that the aqueous mixture prepared in step (a) converts clay. Process according to claim 1, characterized in that the mixture in step (b) is formed by spray drying. 6. Method according to claim 1, characterized in that the ion exchange step (d) comprises contacting the fired particles with a solution comprising ammonium ions and / or rare earth ions. Catalyst material obtained by the method of any of the preceding claims. 8. Fluid cracker catalyst material obtained according to the method of claim 5. 8203099 - 15 - The material according to claim 8, characterized in that the catalyst contains about 0 to 60% by weight of zeolite, 5 to 25% by weight of alumina binder and at most about 90% by weight of clay. Catalyst material according to claim 9, characterized in that the zeolite is a type Y zeolite. 11. Material according to claim 10, characterized in that the zeolite is exchanged with rare earth and / or ammonium ions. 12. Methods and articles essentially as described in the description and / or the examples. 8 / / 8203099