JP2002542929A - Zeolite-bound catalyst containing at least three different zeolites, use for hydrocarbon conversion - Google Patents

Abstract

  (57) [Summary] Provided are zeolite-bound zeolite catalysts that do not contain significant amounts of non-zeolitic binders and that can be manufactured to optimize their performance, and methods of utilizing the zeolite-bound zeolite catalysts to convert hydrocarbons. The zeolite-bound zeolite catalyst comprises a first crystal of a first zeolite and, optionally, a second crystal of a second zeolite having a composition, a structural type, or both, different from the structural type of the first zeolite. And a third crystal of a third zeolite and optionally a fourth crystal of a fourth zeolite having a composition, a structural type, or both, different from the structural type of the third zeolite. Containing binder crystals. If the core crystal does not include the second crystal of the second zeolite, the binder crystal must include the fourth crystal of the fourth zeolite.The zeolite-bound zeolite may be, for example, catalytically cracked, alkylated, toluene-free. It finds application in leveling, isomerization, and transalkylation reactions in hydrocarbon conversion processes.

Description

DETAILED DESCRIPTION OF THE INVENTION

FIELD OF THE INVENTION The present invention relates to a zeolite-bound zeolite catalyst (a zeolite-bound zeolite catalyst) which can be produced to optimize its performance, and to the use of the zeolite-bound zeolite of the preceding paragraph in a hydrocarbon conversion process. About use.

BACKGROUND both natural and synthetic crystalline microporous molecular sieves of the invention have been shown to have catalytic properties for various types for hydrocarbon conversion processes. Also, crystalline microporous molecular sieves have been used as adsorbents, catalyst carriers for various types of hydrocarbon conversion processes, and other uses. These molecular sieves are ordered porous crystalline materials with a certain crystalline structure as determined by x-ray diffraction, in which there are a number of smaller cavities, some of which are several cavities. Can be interconnected by several even smaller channels or pores. The dimensions of the channels or pores are such that they allow the adsorption of molecules having a particular size, while rejecting larger molecules. The void spaces or channels formed by the crystalline network are formed by molecular sieves such as crystalline silicates, aluminosilicates, crystalline silicoaluminophosphates and crystalline aluminophosphates by separation methods and a wide variety of hydrocarbon conversions. It can be used as a molecular sieve in catalysts and catalyst supports in the process.

In the pores of crystalline molecular sieves, hydrocarbon conversion reactions such as paraffin isomerization, olefin skeleton or double bond isomerization, disproportionation, alkylation and transalkylation of aromatic compounds are carried out by the molecular sieve. Governed by constraints imposed by the channel size.
If some fraction of the feed is too large to enter the reacting pores, reactant selectivity will occur, while some of the product will not be able to exit the channel or subsequently react. Product selectivity results. Because the transition state of a particular reaction is too large to be formed within the pore, the product distribution may be altered by the transition state selectivity in which the reaction does not occur. As the size of the molecule approaches the size of the pore system, selectivity also increases in configuration in diffusion.
on). Non-selective reactions at the surface of the molecular sieve, such as reactions at the surface acid sites of the molecular sieve, are generally undesirable. This is because such reactions are not subject to the shape selectivity constraints imposed on those reactions that occur within the channels of the molecular sieve.

[0004] Zeolites are crystalline microporous molecular sieves containing lattice silica and any alumina combined with exchangeable cations such as alkali metal ions or alkaline earth metal ions. The term "zeolite" includes materials containing silica and, optionally, alumina, but it is recognized that the silica and alumina portions can be wholly or partially replaced with other oxides. For example, germanium oxide, titanium oxide, tin oxide, diphosphorus trioxide and mixtures thereof can replace the silica moiety.
Boron oxide, iron oxide, gallium oxide, indium oxide, and mixtures thereof can replace the alumina moiety. Thus, as used herein, singular or plural "zeolites" and "zeolite materials" means only those materials that contain silicon atoms and optionally aluminum atoms in their crystalline lattice structure. Instead, gallosilicates, gallate silicates, silicoaluminophosphates (SAPO) and aluminophosphates containing atoms that appropriately replace such silicon and aluminum (
Substances such as (ALPO) are also meant. As used herein, the term "aluminosilicate zeolite" refers to zeolite materials that consist essentially of silicon and aluminum atoms in their crystalline lattice structure.

In certain hydrocarbon conversion processes, it is sometimes desirable to make the catalyst used in the process maximize its performance in a particular hydrocarbon conversion process. For example, the catalyst used in the hydrocarbon conversion method is a multifunctional catalyst, for example,
It is sometimes desirable to be a trifunctional or bifunctional catalyst. Bifunctional catalysts are two separate catalysts that cause separate reactions, for example, two having different compositions or structural types.
Contains three zeolites. The reaction products can be individual or can be combined such that the reaction product of one catalyst is carried to the catalytic site of a second catalyst and reacts at that catalytic site.
Two catalysts can be used together. Also, one of the benefits of using a zeolite catalyst is that the catalyst is shape-selective, and since non-selective reactions at the surface of the zeolite are usually undesirable, the catalyst used in the hydrocarbon conversion process may be a feed stream. By selectively sieving the molecules in the feed stream based on their size or shape to prevent unwanted molecules present therein from entering the catalyst phase of the zeolite catalyst and reacting with the catalyst. It is sometimes desirable to have the ability to prevent or at least reduce any undesirable reactions that may occur at the surface of the zeolite catalyst. Also, the performance of zeolite catalysts is sometimes maximized if the catalyst selectively screens the desired molecules based on their size or shape to prevent the molecules from exiting the catalytic phase of the catalyst. obtain.

[0006] In the past, hydrocarbon conversions using catalysts containing two different zeolites have been proposed. For example, US Pat. No. 5,536,687 relates to a hydrocracking process using a catalyst containing crystals of zeolite beta and zeolite Y bound by an amorphous binder material such as alumina.

[0007] Although zeolite crystals have good adsorption properties, their practical use is very limited because of the difficulty in operating fixed beds with zeolite powder. Thus, mechanical strength is usually imparted on the zeolite crystals by forming a zeolite conjugate such as a tablet, sphere or extrudate before using the crystals in an industrial process. Extrudates can be formed by extruding zeolite crystals in the presence of a non-zeolitic binder, drying and calcining the resulting extrudate.
The binder material used is resistant to temperature and other conditions that occur in various hydrocarbon conversion processes, such as mechanical attrition. Zeolite is mechanically ground,
That is, it must be resistant to the formation of small particles, for example, a fine powder that is a particle having a size of less than 20 microns. Examples of suitable binders include:
Amorphous materials such as alumina, silica, titania and various types of clay are included.

[0008] Such bound zeolite conjugates have significantly better mechanical strength than zeolite powder, but when using bound zeolites in a catalytic conversion process, the performance of the catalyst, such as activity, Selectivity, activity retention, or a combination thereof, can be reduced due to the amorphous binder. For example, the amorphous binder dilutes the adsorption properties of the zeolite conjugate because the binder is typically present in an amount up to about 60% by weight of the bound catalyst. Alternatively, an amorphous binder may be used to extrude or otherwise form the zeolite, followed by drying and calcining the extrudate to produce a bonded zeolite, thus producing an amorphous binder. Penetrates the zeolite pores or otherwise blocks access to the zeolite pores,
Alternatively, the rate of mass transfer from or to the pores of the zeolite may be slowed, thereby reducing the effectiveness of the zeolite when used in hydrocarbon conversion processes and other applications. Further, when bound zeolites are used in the catalytic conversion process, amorphous binders can affect the chemical reactions that take place within the zeolites, and can themselves catalyze unwanted reactions. , Thereby resulting in the formation of undesirable products. Accordingly, it is desirable that the zeolite catalyst used in hydrocarbon conversion not contain detrimental amounts of such binders.

[0009] The present invention provides a zeolite-bound zeolite catalyst for use in a hydrocarbon conversion process that can be manufactured to overcome or at least reduce the problems described above and maximize zeolite performance. I do.

SUMMARY OF THE INVENTION The present invention relates to a zeolite-bound zeolite catalyst that can be prepared to optimize its performance in hydrocarbon conversion. The zeolite-bound zeolite catalyst is the first
A core crystal comprising a second crystal of a second zeolite having a different composition or structural type than the first zeolite of the preceding paragraph, and a third crystal of a third zeolite And a binder crystal containing a fourth crystal of a fourth zeolite having a different composition or structural type than the third zeolite of the preceding paragraph. When the zeolite-bound zeolite catalyst core crystals do not contain, in addition to the first crystals of the first zeolite, the second crystals of the second zeolite,
The binder crystals contain, in addition to the third crystals of the third zeolite, the fourth crystals of the fourth zeolite. The zeolite-bound zeolite catalyst can contain both a second crystal of the second zeolite and a fourth crystal of the fourth zeolite. The structure type and / or composition of those zeolites is usually manufactured to provide a zeolite-bound zeolite catalyst with increased performance. For example, the zeolite-bound zeolite catalyst may be manufactured to be polyfunctional and / or manufactured to prevent unwanted molecules from entering or exiting the catalyst phase of the zeolite-bound zeolite catalyst. obtain.

In another aspect, the present invention provides a process for converting a hydrocarbon feed using a zeolite-bound zeolite catalyst. Examples of such methods include those in which catalytic acidity combined with the zeolite structure is important for reaction selectivity, such as catalytic cracking, alkylation, dealkylation, disproportionation, and transalkylation reactions. . The process also finds particular use in hydrocarbon conversion processes in which a carbon-containing compound is converted to a different carbon-containing compound. Examples of such methods include dehydrogenation, hydrocracking, isomerization, dewaxing, oligomerization and reforming methods.

[0012] In a preferred embodiment of the Detailed Description of the Invention The present invention, the core zeolite crystals bound zeolite catalyst will contain a second crystal of the first crystal and second zeolite of the first zeolite. The second zeolite has a different composition, structural type, or both, than the first zeolite, and the binder will include a third crystal of the third zeolite.
The composition, structure type of the first zeolite can be the same or different from the composition, structure type, or both of the third zeolite.

In another preferred embodiment, the core crystal of the zeolite-bound zeolite catalyst comprises a first crystal of a first zeolite and the binder is a third crystal of a third zeolite and a second crystal of a fourth zeolite. 4 will be included. The fourth zeolite is the third
Has a different composition, structural type, or both, than the zeolite. The composition, structure type of the first zeolite can be the same or different from the composition, structure type, or both of the third zeolite.

[0014] The presence of a second zeolite, a fourth zeolite, or both, on a zeolite-bound zeolite catalyst offers many advantages. For example, the presence of a zeolite may maximize catalyst performance for a particular hydrocarbon conversion process. For example, in catalytic cracking, a zeolite-bound zeolite core crystal can include two zeolites having different structures, for example, a first zeolite can have large or intermediate pore sizes and a second Can have a smaller pore size than the first zeolite (medium or small pores if the first zeolite has large pores, and if the first zeolite is mesopores) Are small pores), resulting in an increased amount of the desired product being produced.

If there are four zeolites in the zeolite-bound zeolite, the zeolite-bound zeolites may have four zeolites, each having a different composition, structure type, or both. The zeolite-bound zeolite catalyst comprises a first, second, third
In addition to the first and fourth zeolites, further additional zeolites may be included. The additional zeolites may have different compositions, structural types, or both, and these zeolites may be present in core crystals, binder crystals, or both.

In addition to the zeolite-bound zeolite catalyst having the ability to be multifunctional, the zeolite binder crystals may provide a means to control unwanted reactions that occur on or near the outer surface of the core crystal and / or It can affect the mass transfer of hydrocarbon molecules through the pores. Instead, if desired, the binder crystals have catalytic activity, function as a catalyst carrier, and / or selectively prevent unwanted entry and exit of molecules from the pores of the first and second zeolites. I can do it.

Although the present invention is not intended to be limited to any theory of operation, one advantage of the zeolite-bound zeolite catalyst of the present invention is that the accessibility of acidic sites on the outer surface of the core crystal to the reactants. Is believed to be obtained by zeolite binder crystals that control the Since acidic sites present on the outer surface of the zeolite catalyst are not shape-selective, these acidic sites can adversely affect reactants entering the zeolite pores and products exiting the zeolite pores. In accordance with this belief, the acidity and structural type of the binder can be carefully selected, so that the binder does not significantly affect the reactants present in the zeolite pores of the core crystal, which can occur with a conveniently bound zeolite catalyst, And will have a beneficial effect on the reactants exiting the pores of the zeolite. Furthermore, the zeolite binder is not amorphous, but instead has a molecular sieve, so that access to the pores of the core crystal during the hydrocarbon conversion process will increase. Regardless of the proposed theory, when used in a catalytic process, the zeolite-bound zeolite catalyst has one or more improved properties disclosed herein.

[0018] The zeolite-bound zeolite catalysts of the present invention generally do not contain significant amounts of non-zeolitic binders. The zeolite-bound zeolite catalyst is preferably a catalyst comprising less than 10% by weight, more preferably less than 5% by weight, based on catalyst weight, of a non-zeolitic binder, and most preferably a catalyst substantially free of non-zeolitic binder. Preferably, the binder crystal binds to the core crystal by attaching to the surface of the core crystal, thereby forming a matrix or bridge structure that also holds the core crystal together.

The terms “acidity”, “lower acidity”, “moderate acidity” and “higher acidity” as used for zeolites are known to those skilled in the art. The acidic properties of zeolites are well known. However, for the present invention, a distinction must be made between acidic strength and acidic site density. The acidic site of the zeolite can be a Bronsted or Lewis acid. The density of acidic sites and the number of acidic sites are important in determining the acidity of a zeolite. Factors directly affecting the acid strength are 1) the chemical composition of the zeolite framework (frame structure), ie, the relative density and type of tetrahedral atoms, 2)
Cation concentration and the resulting extra-framework species, 3) local structure of the zeolite, eg, zeolite crystals, pore size and location at or near the surface, 4) pretreatment conditions and the presence of co-adsorbed molecules It is. The amount of acidity is related to the degree of isomorphous substitution provided, but such acidity is limited to the loss of acid sites for a pure SiO ₂ composition. As used herein, the terms "lower acidity" and "
"Higher acidity" refers to the concentration of acidic sites regardless of the intensity of such acidic sites, which can be measured by ammonia absorption.

[0020] Zeolites suitable for use in the zeolite-bound zeolite catalysts of the present invention include any of the natural or synthetic crystalline zeolites. Examples of these zeolites include large pore zeolites, medium size zeolites and small pore zeolites. These zeolites are available from WH Meier, HD Olson and Ch. Baerlocher, Elsev.
ier, "Zeolite Structural Type Charts" (4th edition, 1996). That document is incorporated herein by reference. Generally large pore zeolites have at least 7
Angstrom pore size, LTL, VFI, MAZ, MEI, FA
U, EMT, OFF, ^* BEA and MOR structured zeolites (IUPAC Commission
of Zeolite Nomenclature). Examples of large pore zeolites are mazzite, offretite, zeolite L, VPI-5, zeolite Y, zeolite X, omega, beta, ZSM-3, ZSM-4, ZSM-18, ZSM-20, MCM-9.
, MCM-41. MCM-41S, MCM-48 and SAPO-37. Generally, medium pore size zeolites have a pore size of about 5 Å to 7 Å, for example, MFI, MEL, MTW, EUO, MTT, HE
U, FER, MFS and TON structured zeolites (IUPAC Commission of Zeolit)
e Nomenclature). Examples of mesopore size zeolites are ZSM-5, ZS
M-12, ZSM-22, ZSM-23, ZSM-34, ZSM-35, ZSM
-38, ZSM-48, ZSM-50, ZSM-57, MCM-22, MCM-
36, MCM-49, MCM-56, MCM-68, silicalite (silicic)
alite) and silicalite 2. Small pore size zeolites have a pore size of about 3 Angstroms to 5.0 Angstroms, for example CHA,
ERI, KFI, LEV and LTA structured zeolites (IUPAC Commission of Ze)
olite Nomenclature). Examples of small pore zeolites are ZK-4, SAPO-
34, SAPO-35, ZK-14, SAPO-42, ZK-21, ZK-22
, ZK-5, ZK-20, zeolite A, erionite, shabasite, zeolite T, gmelinite, ALPO-17 and clinotyrolite.

The first, second, third and fourth zeolite-bound zeolite catalysts used
The zeolite preferably comprises a composition having the following molar relationship:

X ₂ O ₃ : (n) YO ₂ where X is a trivalent element such as titanium, boron, aluminum, iron, and gallium, and Y is a tetravalent element such as silicon, tin, and germanium. Where n has a value of at least 2, which value depends on the particular type of zeolite and the trivalent element present in the zeolite.

If the first, second, third and fourth zeolites have an intermediate pore size, the zeolite preferably comprises a composition having the following molar relationship:

X ₂ O ₃ : (n) YO ₂ where X is a trivalent element such as aluminum and gallium, Y is a tetravalent element such as silicon, tin and germanium, and n is 10 It has a larger value, which value depends on the particular type of zeolite and the trivalent element present in the zeolite. If the zeolite has an MFI structure, n is preferably greater than 20.

As known to those skilled in the art, the acidity of zeolites can be reduced using a number of techniques, such as by dealumination and exposure to steam. Furthermore, the acidity of zeolites depends on the form of the zeolite, the hydrogen form has the highest acidity, and other forms of the zeolite, such as the sodium form, are less acidic than the acid form. Therefore,
The molar ratios of silica to alumina and silica to gallium disclosed herein should include not only zeolites with the disclosed molar ratios, but also zeolites that do not have the disclosed molar ratios but have equivalent catalytic activity. is there.

If the first zeolite, the second zeolite, the third zeolite or the fourth zeolite is a gallate silicate mesopore size zeolite, the zeolite preferably comprises a composition having the following molar relationship: : Ga ₂ O ₃ : ySiO ₂ where y is from about 24 to about 500. The zeolite framework may contain only gallium and silicon atoms or a combination of gallium, aluminum and silicon.
If the first or second zeolite is an MFI-structured gallic silicate zeolite,
The binder zeolite has a silica to gallia greater than 100
It will be preferred to be a mesopore size zeolite having a molar ratio of The binder zeolite may also have a silica to gallium molar ratio of, for example, greater than 200, 500, 1000, etc.

If the first zeolite used in the zeolite-bound zeolite catalyst and, if present, the second zeolite is an aluminosilicate zeolite, the molar ratio of silica to alumina is usually determined by the structure type of the zeolite and its catalyst system. Depending on the particular hydrocarbon process utilized, it is not limited to any particular ratio. However, generally and depending on the structure type of the zeolite, the zeolite will have a silica to alumina molar ratio of at least 2: 1 and in some cases from 4: 1 to about 7: 1. For some zeolites, especially mesoporous zeolites, the silica to alumina molar ratio ranges from about 10: 1 to 1000: 1. The catalyst is
If used in acidic catalyzed reactions such as para-xylene and benzene production by cracking, disproportionation of toluene and alkylation of benzene, etc., at least one zeolite is acidic and if it is a mesopore size zeolite. If so, it would have a higher silica to alumina ratio, for example, from 20: 1 to about 200: 1.
If the catalyst is used in a process and an acidic catalysis reaction is not desired, such as in the reforming of naphtha, the first zeolite and, if any, the second zeolite may have reduced acid activity. Preferably it is shown.

The composition and structural type of the first and second zeolites will depend on the particular hydrocarbon process in which the zeolite catalyst is used. For example, if a catalyst is used to modify naphtha to aromatics, the structural type is LTL (eg, zeolite L) and has a silica to alumina ratio of 4: 1 to about 7: 1. Would be preferred. If the catalyst is to be used for the production of para-xylene and benzene by xylene isomerization or toluene heterogeneity, the first zeolite and the second zeolite (optionally present) have a medium pore size zeolite. Is preferred. If a zeolite-bound zeolite catalyst is to be used to break down paraffins, the preferred pore size and structural type will depend on the size of the molecule to be broken down and the desired product.

As used herein, the term “average particle size” refers to the arithmetic mean of the diameter distribution of crystals on a volume basis.

[0030] The average particle size of the core crystals will vary and will typically be from about 0.1 to about 15 microns. For some applications, it is preferred that the average particle size be at least about 1 to 6 microns. For other applications, such as hydrocarbon cracking, the preferred average particle size is from about 0.1 to about 3.0 microns. The core crystal is the first of the first zeolite
And the second crystal of the second zeolite, the average particle size of the first crystal is sometimes greater than twice the average crystal size of the second crystal. Also, if both crystals are present, the amount of second crystals present can vary, for example, less than 5% by weight based on the weight of the first and second crystals. Can be even small amounts.

The composition and structural type of the third zeolite and the fourth zeolite, if any, are
It will depend on the intended use of the zeolite-bound zeolite catalyst. For example, if the zeolite-bound zeolite catalyst comprises a first zeolite and a second zeolite core crystal and a third zeolite binder crystal and is used as a xylene isomerization and ethylbenzene dealkylation catalyst, the first zeolite may be: Can be selected as follows. That is, dealkylation of ethylbenzene occurs in the first zeolite catalyst phase, xylene isomerization occurs mainly in the second zeolite catalyst phase,
It is provided that a binder zeolite can be selected to reduce the surface acidity of the first and second zeolites. If a zeolite-bound zeolite catalyst is to be used in the cracking process, the zeolite can have acidic activity and the structural type of each zeolite will increase its pore size where larger molecules are fractionated into smaller products. It can be selected to allow larger molecules to enter into the channel. After the larger molecules have been fractionated, the fractionated molecules can then enter the pores of the smaller pore size zeolite, where they can be further purified depending on the desired resulting product. It is capable of undergoing decomposition, isomerization or oligomerization. The zeolite-bound zeolite catalyst can also be prepared by adapting the binder crystal zeolite to sieve the feed components that enter the pores of the zeolite core crystals or the product components that exit the channels of the zeolite core crystals. For example, if the zeolite-bound zeolite catalyst includes a zeolite of a suitable pore size binder, for example, a third and optionally a fourth zeolite, it will screen the molecules based on the size or shape of the molecules and It can function to classify, thereby preventing unwanted molecules from entering and exiting the catalytic phase of the zeolite core crystals, as is the case.

If the third and fourth zeolites are aluminosilicate zeolites, the silica to alumina molar ratio usually depends on the zeolite structure type and the particular hydrocarbon process in which the catalyst is utilized, and therefore It will not be limited to any particular ratio.
However, generally and depending on the structure type of the zeolite, the ratio of silica to alumina will be at least 2: 1. In applications where the aluminosilicate zeolite is a mesopore size zeolite and low acidity is preferred, the binder zeolite preferably has a silica to alumina molar ratio greater than the silica to alumina molar ratio of the first zeolite. , More preferably greater than 200: 1. The binder zeolite has a higher silica to alumina molar ratio, for example, 300: 1, 500:
1, 1000: 1 etc. can be carried as well. Binder zeolites are silicalite (ie, the zeolite is of a substantially alumina-free MFI structure type), silicalite 2 (ie, the zeolite is of a substantially alumina-free MEL structure type), and mixtures thereof. . The pore size of the binder zeolite is preferably such that it does not adversely limit the access of the desired molecules of the hydrocarbon feed stream to the catalyst phase of the zeolite-bound zeolite. For example, if the feed stream material to be converted by the zeolite core crystals has a size of 5 Angstroms to 6.8 Angstroms, then the binder zeolite is preferably a large pore zeolite or a medium pore size zeolite.

Usually, binder crystals are present in the zeolite-bound zeolite catalyst in amounts ranging from about 10 to 60% by weight, based on the weight of the catalyst, but the amount of binder crystals present is usually Will depend on More preferably, the amount of binder crystals present is about 20 to 50% by weight. If the binder crystals include a third crystal of the third zeolite and a fourth crystal of the fourth zeolite, the average particle size of the third crystals is smaller or larger than the average particle size of the fourth crystals. obtain.

If the third and fourth crystals are present in the zeolite-bound zeolite catalyst, the amount of fourth crystals present can vary and is based on the weight of the third and fourth crystals. Thus, for example, it can be as small as less than 20% by weight.

The binder crystals usually have a smaller size than the core crystals. Desirably, the binder crystals have an average particle size of less than 1 micron, from about 0.1 to 0.5
Microns are preferred. The binder crystals, in addition to binding the core crystals and maximizing the performance of the catalyst, intergrow and overgrow or partially overlap over the first zeolite. If a second zeolite is present, the binder crystals can also grow over this zeolite. If the binder crystals comprise crystals of two zeolites having different compositions, structural types, or both, the average particle size of each may be the same or different. That is, it can be larger or smaller. Sometimes, the coating will withstand attrition.

The amount of the second zeolite and the fourth zeolite present in the zeolite-bound zeolite catalyst generally depends on the particular zeolite-bound zeolite catalyst process, and usually ranges from about 1.0 to 70% by weight based on the weight of the catalyst. In the range.

The zeolite-bound zeolite catalyst can be prepared using a three-step procedure. The first step involves the synthesis of zeolite core crystals. Processes for preparing these zeolites are known to those skilled in the art. For example, the MFI structure type zeolite is
It can be prepared using the process described in PCT Publication No. WO 98/16469. That document is incorporated herein by reference. If the core crystals comprise a first zeolite crystal and a second zeolite crystal, the zeolites can be made individually or by converting the synthesis mixture under conditions that favor two separate zeolites. . For example, MFI and MEL structural zeolites may be made from the same zeolite synthesis mixture.

Next, the silica-bound zeolite is prepared by mixing a mixture comprising core crystals, silica gel or sol, water and any extrusion aids in the form of an extrudable paste until a homogeneous composition results. Is preferred. The silica binder used to prepare the silica-bound zeolite conjugate is desirably a silica sol and can include various amounts of trivalent metal oxides such as alumina. The amount of zeolite in the dried extrudate at this stage is preferably in the range of about 40 to 90% by weight, and
More preferably, it has a balance of predominantly silica in the range of from about 80% by weight to about 80% by weight, for example, from 20 to 50% by weight.

The resulting paste is, for example, extruded, cut into small strips of 2 mm diameter, for example, by extrusion, dried at 100-150 ° C. for 4-12 hours,
It is fired in air at about 400-550 ° C. for about 1-10 hours.

[0040] Optionally, the silica-bound conjugate can be made into very small particles used in fluidized bed processes such as catalytic reforming. This involves mixing the core crystal zeolite with the silica containing the matrix solution so that an aqueous solution of the zeolite and the silica binder is formed, which is spray-dried into small fluidizable silica-bound binder particles. You can be made to come back. Procedures for preparing such conjugate particles are known to those skilled in the art. Examples of such procedures are described by Scherzer (Octane-Enhancing Zeolotic FCC Catalysts, Julius Scherzer, Mar.
cel Dekker, Inc. New York, 1990). The fluidizable silica-bonded conjugate particles, similar to the silica-bonded extrudates described above, then undergo the following final steps to convert the silica binder to a second zeolite.

The final step in the three-step catalyst preparation process is to convert the silica present in the silica-bound zeolite to a binder zeolite. The binder crystals bind the core crystals together. Without using a significant amount of non-zeolitic binder, the zeolite core crystals are thus kept apart.

To prepare the zeolite-bound zeolites, the silica-bound conjugate is preferably first aged in a suitable aqueous solution at an overly elevated temperature. Next, the temperature at which the contents of the solution and the conjugate are aged to convert the amorphous silica binder to one or more zeolites is selected. Newly formed zeolites, which can include more than one zeolite, are produced as crystals. Crystals can grow on and adhere to the core crystal, and can also be produced in the form of new, intergrown crystals, which are generally much greater than the original crystals, eg, 1 micron or less in size. Small. These newly formed crystals grow together and interconnect.

The properties of the zeolite formed in the secondary synthetic conversion of silica to zeolite are:
It can vary as a function of the composition of the secondary synthesis solution and the conditions of the synthesis ripening. The secondary synthesis solution is desirably an aqueous ionic solution that contains a sufficient source of hydroxyl ions to convert the silica to the desired zeolite, which may be two or more zeolites. However, it is important that the aging solution has a composition that does not elute the silica present in the bound zeolite extrudate from the extrudate. At times, it may be preferable to dissolve a portion of the zeolite crystals to form one or more zeolites having different compositions, structural types, or both. At other times, it may not be desirable to melt the zeolite crystals.

[0044] At least some of the raw metals present in the zeolite are replaced with Group IB to VIII metal cations of the Periodic Table such as, for example, nickel, copper, zinc, calcium or rare earth metals, or intermediate ammonium and alkali metals. The zeolite present in the zeolite-bound zeolite catalyst, either for exchange and subsequent calcination of the ammonium form to give the acidic hydrogen form, gives rise to additional ions as is known in the art. Can be exchanged. Acidic forms can be readily prepared by ion exchange with a suitable acidic reagent, such as ammonium nitrate. The zeolite is then calcined at a temperature of 400-550 ° C. for 10-45 hours to remove ammonia and form an acidic hydrogen form.
Particularly preferred cations are those which render the catalyst catalytically active, especially for hydrocarbon conversion processes. These are hydrogen, rare earth metals and group IIA of the Periodic Table of the Elements.
, IIIA, IVA, IB, IIB, IIIB, IVB and VIII metals. Preferred metals are Group VIII metals (ie, Pt, Pd, Ir, Rh, Os, Ru, Ni, Co, and Fe), Group
IVA metals (ie, Sn and Pb), Group VB metals (ie, Sb and Bi), Group VII
B metal (ie, Mn, Tc, and Re). Noble metals (ie Pt, Pd, Ir, Rh, Os,
And Ru) are sometimes even more preferred.

[0045] The zeolite-bound zeolite catalyst of the present invention can be used to treat hydrocarbon feedstocks. The hydrocarbon feedstock contains carbon compounds and can be any carbon obtained from many different sources, such as natural petroleum fractions, reclaimed petroleum fractions, bitumen oils, and generally contains fluids capable of zeolite catalysis . Depending on the type of treatment that the hydrocarbon feed undergoes, the feed may be metal-free or metal-free.

The conversion of the hydrocarbon feed may take place in any convenient mode, for example in a fluidized bed, moving bed or fixed bed reactor, depending on the type of process desired.

The zeolite-bound zeolite catalysts of the present invention, alone or in combination with one or more catalytically active substances, can be used in a variety of organic,
For example, it can be used as a catalyst or carrier for a hydrocarbon compound conversion process. Examples of such conversion processes include, by way of non-limiting example, the following:

(A) Catalytic cracking of naphtha feed to produce light olefins. Typical reaction conditions are from about 500 ° C. to about 750 ° C., subatmospheric or atmospheric pressure, generally about 1
Including pressures in the range of up to 0 atmospheres (gauge), and residence times (amount of catalyst feed rate) of about 10 milliseconds to about 10 seconds.

(B) Catalytic cracking of high molecular weight hydrocarbons to low molecular weight hydrocarbons. Typical reaction conditions for catalytic cracking are temperatures from about 400 ° C. to about 700 ° C., about 0.1 atm (bar)
Pressures of from about 30 to about 30 atmospheres, and weight hourly space velocities of from about 0.1 to about 100 hr ^-1 .

(C) Transalkylation of aromatic hydrocarbon in the presence of polyalkyl aromatic hydrocarbon. Typical reaction conditions include a temperature of about 200 ° C. to about 500 ° C., a pressure of about atmospheric to about 200 atmospheres, a weight hourly space velocity of about 1 to about 200 hr ⁻¹ , and about 0
. It contains an aromatic hydrocarbon / polyalkyl aromatic hydrocarbon molar ratio of from 5/1 to about 16/1.

(D) Isomerization of aromatic (eg, xylene) feed components. Typical reaction conditions for the isomerization include a temperature of about 230 ° C. to about 510 ° C., a pressure of about 0.5 atm to about 50 atm, a weight hourly space velocity of about 0.1 to about 200 hr ⁻¹ , and about It contains a hydrogen / hydrocarbon molar ratio of 0 to about 100.

(E) Dewaxing of hydrocarbons by selective removal of normal paraffins. The reaction conditions are
It largely depends on the feed used and the desired pour point. Typical reaction conditions are about 2
Includes temperatures between 00 ° C. and 450 ° C., pressures up to 3000 psig, and liquid hourly space velocities of 0.1-20.

(F) Alkylating agents, such as olefins having from 1 to about 20 carbon atoms, formaldehyde, alkyl halides, and alcohols, in the presence of an aromatic hydrocarbon, such as benzene and alkylbenzene. Alkylation. Typical reaction conditions include a temperature of from about 100 ° C. to about 500 ° C., a pressure of from about atmospheric to about 200 atmospheres, a weight hourly space velocity of from about ^{1hr -1} to about 100 hr ^-1, and from about 1/1 to about 20 / Contains an aromatic hydrocarbon / alkylating agent molar ratio of 1.

(G) Long-chain olefins such as C₁₄Olefins, by aromatic hydrocarbons,
For example, alkylation of benzene. Typical reaction conditions are from about 50 ° C to about 200 ° C.
Temperature, pressure from about atmospheric pressure to about 200 atmospheres, about 2 hours^-1~ 2000 hr ^-1 Weight hourly space velocity and about 1/1 to about 20/1 aromatic hydrocarbon / oleate
Includes fin molar ratio. The product of this reaction is a long chain alkyl aromatic
, Which, when subsequently sulfonated, has a special use as a detergent
.

(H) Alkylation of aromatic hydrocarbons with light olefins to provide short chain alkylaromatics, for example, alkylation of benzene with propylene to provide cumene. Typical reaction conditions are temperatures from about 10 ° C to about 200 ° C, about 1 ° C.
From about 30 atm to about 30 atm, and from 1 hr ^{-1 to} about 50 hr ^-1 of aromatic hydrocarbon hourly space velocity (WHSV).

(I) Hydrocracking of heavy petroleum feedstocks, cyclic feedstocks, and other hydrocracked feedstocks. The zeolite catalyst contains an effective amount of at least one hydrogenation component of the type used in the hydrocracking catalyst.

(J) Short-chain olefins (eg, for producing mono- and dialkylates)
Alkylation of reformate containing significant amounts of benzene and toluene with fuel gas containing ethylene and propylene. Preferred reaction conditions are from about 100 ° C. to about 250
° C, about 689.5 to 5516 kPa (about 100 to about 800 psig)
Pressure, about 0.4 hr ^{-1 to} about 0.8 hr ^-1 olefin WHSV, about 1 hr.
WHSV of the reformate from about hr ^{-1 to} about 2 hr ^-1 and optionally about 1.5 to 2.5 volumes of gas recirculation per volume of fuel gas feed.

(K) Alkyl of aromatic hydrocarbons, such as benzene, toluene, xylene, and naphthalene, with long-chain olefins, such as C ₁₄ olefins, to produce alkylated aromatic lubricant-based feedstocks Conversion. Typical reaction conditions are about 16
Includes a temperature of 0 ° C. to about 260 ° C. and a pressure of about 350 to 450 psig.

(L) Alkylation of phenol with an olefin or equivalent alcohol to provide a long chain alkyl phenol. Typical reaction conditions are from about 100 ° C. to about 25
0 ° C., about 6.895 to 2068.5 kPa (about 1 to 300 psig)
And a total WHSV of 2 hr ^{-1 to} about 10 hr ^-1 .

(M) Conversion of light paraffins to olefins and / or aromatics. Typical reaction conditions are a temperature of about 425 ° C. to about 760 ° C. and about 68.95 to 13790 kPa
(About 10 to about 2000 psig). A method for preparing aromatics from light paraffin is described in US Pat. No. 5,258,563,
This is incorporated herein by reference.

(N) Conversion of light olefins to gasoline, distillate, and lubricant range hydrocarbons. Typical reaction conditions include a temperature of about 175 ° C to about 375 ° C and a pressure of about 689.5 to about 13790 kPa (about 100 to about 2000 psig).

(O) Two Stages for Upgrading Hydrocarbon Streams Having an Initial Boiling Point Above about 200 ° C. to Rare Distillates and Gasoline Boiling Range Products, or to Feeds or Further to Fuels or Chemicals Hydrocracking. In the first stage, the zeolite-bound zeolite comprising one or more catalytically active substances, for example a Group VIII metal, and the effluent from the first stage is separated in the second stage by one The reaction is performed using a second zeolite catalyst containing the above catalytically active substance, for example, a Group VIII metal, for example, zeolite beta. Typical reaction conditions are approximately 31
5 ° C. to about 455 ° C., about 2758 to about 17237.5 kPa (about 400
To about 2500 psig) at a pressure of about 1000 to about 10,000 SCF / b.
bl hydrogen circulation and a liquid hourly space velocity (LHSV) of about 0.1 to 10.

(P) Combined hydrocracking / dewaxing process in the presence of a zeolite-bound zeolite catalyst comprising a metal hydride and a zeolite such as zeolite beta. Typical reaction conditions are temperatures from about 350 ° C. to about 400 ° C., from about 9653 to about 10342.
. 5 kPa (about 1400 to about 1500 psig) pressure, about 0.4 to about 0.4 psig.
6 LHSV and a hydrogen cycle of about 3000 to about 5000 SCF / bbl.

(Q) Reaction of alcohols with olefins to produce mixed ethers, for example, methanol and isobutene and / or to produce methyl-t-butyl ether (MTBE) and / or t-amyl methyl ether (TAME). Or the reaction of isopentene. Typical reaction conditions are temperatures from about 20 ° C. to about 200 ° C., 2 to about 200 ° C.
pressure atm, (grams olefin per zeolite 1g per hour) WHSV of about 0.1 hr ^-1 to about 200 hr ^-1, and about 0.1 / 1 to about 5
/ 1 molar feed ratio of alcohol to olefin.

(R) Disproportionation of aromatics, for example to produce benzene and para-xylene
Disproportionation of toluene. Typical reaction conditions are temperatures from about 200 ° C. to about 760 ° C., approximately
From atmospheric pressure to about 60 atm (bar) and about 0.1 hr^-1~ 30hr ^-1 WHSV.

(S) Conversion of naphtha (eg, C ₆ -C ₁₀ ) and similar mixtures to highly aromatic mixtures. Thus, normal and slightly branched hydrocarbons, preferably having a boiling range above about 40 ° C. and below about 200 ° C., are converted into products having substantially higher octane aromatic content, About 400 hydrocarbon feeds.
At a temperature in the range of from 480 to 550 ° C, a pressure in the range of from atmospheric pressure to 40 bar, and a liquid hourly space velocity (LHSV) in the range of from 0.1 to 15. The conversion can be achieved by contact with the bound zeolite.

(T) Selective separation of hydrocarbons by adsorption of hydrocarbons. Examples of hydrocarbon separation are:
Includes the separation of xylene isomers and the separation of olefins from feed streams containing olefins and paraffins.

(U) Conversion of oxygenates, for example alcohols such as methanol, or ethers such as dimethyl ether, or mixtures thereof, to hydrocarbons containing olefins and aromatics. Reaction conditions include a temperature of about 275 ° C. to about 600 ° C., a pressure of about 0.5 to about 50 atmospheres, and a liquid hourly space velocity of about 0.1 to about 100.

(V) Oligomerization of linear and branched olefins having about 2 to about 5 carbon atoms. The oligomers that are the product of this process are medium to heavy olefins useful for both fuels, ie, gasoline or gasoline blending stocks, and chemicals. The oligomerization process generally involves converting the gaseous phase olefin feed with a zeolite catalyst, a temperature in the range of about 250 ° C to about 800 ° C, an LHSV of about 0.2 to about 50, and about 0.1 to about 50 ° C. This is done by contacting at a hydrocarbon partial pressure of about 50 atm. If the feed is in the liquid phase when contacted with the zeolite catalyst, temperatures below about 250 ° C. can be used to oligomerize the feed. Thus, when the olefin feed contacts the catalyst in the liquid phase,
Temperatures from about 10 ° C to about 250 ° C can be used.

[0070] (W) corresponding _{C 6-12} alcohols _{C 2} unsaturated hydrocarbons (ethylene and / or acetylene) conversion and preceding aldehydes to aliphatic _{C 6- 12} aldehydes,
Conversion to acid or ester.

In general, the catalytic conversion conditions are:
A temperature of about 100 ° C. to about 760 ° C., about 0.1 atm (bar) to about 200 atm (
Bar) and a weight hourly space velocity of from about 0.08 hr ^{-1 to} about 2,000 hr ^-1 .

For many hydrocarbon conversion processes, it is preferred that the binder crystals have lower acidity to reduce unwanted reactions outside the core crystals, but for some processes the binder crystals will have higher acidity. It is preferred to have.

A process that finds particular application using the zeolite-bound zeolite catalysts of the present invention is one in which more than one reaction occurs within the zeolite-bound zeolite catalyst. Each of the zeolites of the catalyst is separately adapted to promote or inhibit different reactions. The process of using such catalysts is not only due to the greater apparent catalytic activity, greater zeolite accessibility, and reduced non-selective surface acidity that are possible with zeolite-bound zeolite catalysts, but also adapted catalysts. Also benefit from the system.

Examples and representative uses of zeolite-bound zeolite catalysts are shown in Table I below.

[0075]

[Table 1]

Examples of preferred zeolite-bound zeolite catalyst systems include:

1. A zeolite comprising a core crystal composed of an acidic first zeolite having a cracking activity and a second zeolite having an acidity smaller than that of the first zeolite and a binder crystal composed of a third zeolite having very low or no acidic activity. Bound zeolite catalyst. This zeolite-bound zeolite catalyst system finds particular use in catalytic cracking. Catalysts E and F in Table I are examples of such catalysts.

2. A core crystal comprising an acidic first zeolite having a large pore with a cracking activity and an acidic second zeolite having a medium pore size and a cracking activity; Intermediate pore (intermed
iate pore) Zeolite-bound zeolite catalyst with binder crystals consisting of size zeolite. Catalyst M in Table I is an example of such a catalyst.

[0079] 3. A first having a moderate acid activity and optionally containing a hydrogenation / dehydrogenation metal;
, A core crystal comprising a second zeolite having an acid activity greater than the first zeolite and optionally with a hydrogenation / dehydrogenation metal, and a third zeolite having a lower acid activity than the first zeolite A zeolite catalyst system comprising a binder crystal comprising: The pore size of these zeolites depends on the type of process in which the catalyst system is used. For example, this catalyst system is used in a combined xylene isomerization / ethylbenzene dealkylation process where ethylbenzene is dealkylated to benzene and ethane and the xylene isomer isomerized to an equilibrium amount. can do. In such a system, the first zeolite preferably has a large or mesopore size zeolite and has a large crystal size, and the second zeolite also preferably has a high surface acidity, preferably It has a larger pore size and a larger crystal size, or has an intermediate pore size zeolite and has a smaller crystal size. Catalyst C in Table I,
D and U are examples of such catalysts.

[0080] 4. A zeolite-bound zeolite catalyst comprising a core crystal composed of a first acidic zeolite and a binder crystal composed of a third zeolite and a fourth zeolite, both of which have little or no acid activity. The pore size of these zeolites depends on the type of process in which the catalyst system is used. For example, if the catalyst is used in the production of benzene and para-xylene by disproportionation of toluene, the first zeolite preferably has a medium pore size and the third and fourth zeolites are One zeolite may be selected to enhance its performance, for example, optionally leaving the first zeolite phase or
Can be selected to screen unwanted molecules exiting the zeolite phase of the first zeolite or to control the accessibility of the acid sites on the outer surface of the first zeolite to the reactants. Catalyst A in Table I is an example of such a catalyst.

The zeolite-bound zeolite catalyst of the present invention has particular application in the vapor phase disproportionation of toluene. Such vapor phase disproportionation contacts toluene under disproportionation conditions with a zeolite-bound zeolite to produce a product mixture comprising a mixture of unreacted (unconverted) toluene, benzene, and xylene. Including. In a more preferred embodiment, the catalyst first imparts selectivity prior to use in the disproportionation process to increase the conversion of toluene to xylene and to maximize the selectivity of the catalyst for para-xylene production. Is done. Methods for imparting selectivity to a catalyst are known to those skilled in the art. For example, providing selectivity
Converts the catalyst in the reactor bed to a thermally decomposable organic compound, such as toluene, at a temperature above the decomposition temperature of the preceding compound, such as from about 480 ° C to about 650 ° C, more preferably from 540 ° C to about 650 ° C. Temperature WHSV in the range of about 0.1 to 20 lbs of feed per pound of catalyst per hour, 0 to about 2 moles of hydrogen per mole of organic compound at pressures in the range of about 1 to 100 atmospheres, more Preferably about 0
. Exposure can be effected in the presence of 1 to about 2 moles of hydrogen, and optionally in the presence of 0 to 10 moles of nitrogen or other inert gas per mole of organic compound. The process is conducted until a sufficient amount of coke has deposited on the catalyst surface, generally at least about 2% by weight, and more preferably about 8 to about 40% by weight of coke. . In a preferred embodiment, such a method of imparting selectivity is performed in the presence of hydrogen to prevent excessive formation of coke on the catalyst.

[0082] Selectivity of the catalyst can also be imparted by treating the catalyst with a selectivity imparting agent such as an organosilicon compound. Examples of organosilicon compounds include silicones, siloxanes, and silanes, including disilanes and alkoxysilanes.

The silicone compounds that find particular use are represented by the formula:

Embedded image Wherein R ₁ is hydrogen, fluoride, hydroxy, alkyl, aralkyl, alkaryl, or fluoro-alkyl. The hydrocarbon substituent generally contains from 1 to 10 carbon atoms and is preferably a methyl or ethyl group. R ₂ is selected from the same group as R _1, and n is an integer of at least 2, and generally in the range of 2 to 1000. The molecular weight of the silicone compounds used is generally between 80 and 20,000, and is preferably between 150 and 10,000. Representative silicone compounds include dimethyl silicone, diethyl silicone, phenylmethyl silicone, methyl hydrogen silicone, ethyl hydrogen silicone, phenyl hydrogen silicone, methyl ethyl silicone, phenyl ethyl silicone, diphenyl silicone, methyl trifluoropropyl silicone, and ethyl trifluoropropyl silicone. , Tetrachlorophenylmethyl silicone, tetrachlorophenylethyl silicone, tetrachlorophenyl hydrogen silicone, tetrachlorophenylphenyl silicone, methyl vinyl silicone, and ethyl vinyl silicone. The silicone compound need not be linear, but may be cyclic, for example, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, hexaphenylcyclotrisiloxane, and octaphenylcyclotetrasiloxane. Mixtures of these compounds as well as silicones with other functional groups can be used.

Useful siloxanes or polysiloxanes include, but are not limited to, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane , Hexaethylcyclotrisiloxane, octaethylcyclotetrasiloxane, hexaphenylcyclotrisiloxane, and octaphenylcyclotetrasiloxane.

Useful silanes, disilanes, or alkoxysilanes have the general formula:

Embedded image Wherein R is a reactive group such as hydrogen, alkoxy, halogen, carboxy, amino, acetamido, trialkylsiloxy, and R ₁ , R ₂ , and R ₃ are R may be the same or an alkyl, alkyl or aryl carboxylic acid of 1 to 40 carbon atoms, wherein the organic part of the alkyl contains 1 to 30 carbon atoms and the aryl group has 6 to 24 carbon atoms. It may be an alkyl or aryl carboxylic acid containing carbon atoms, which may be further substituted, or an organic group containing an alkylaryl and arylalkyl group containing 7 to 30 carbon atoms.

When used for the vapor phase disproportionation of toluene, the catalyst may comprise from about 20 to about 200: 1.
Having a silica to alumina molar ratio of preferably 25: 1 to about 120: 1.
A first crystal of a mesopore size zeolite, such as MFI structure type, having a micron average particle size of about 2 to about 6, having a molar ratio of alumina to silica of greater than about 200: 1 to about 10,000: 1 to silica. Having an intermediate pore size, such as MFI or M
A binder comprising a third crystal having an average particle size of less than about 0.1 micron of an EL structure type, eg, silicalite or silicalite 2, and a different structure type than the first zeolite, eg, a TON structure type. Of medium pore size zeolite having
Second zeolite.

Once the selectivity has been imparted to the catalyst to the desired extent, the conditions for imparting selectivity in the reactor are changed to disproportionation reaction conditions. Disproportionation conditions include temperatures between about 400 ° C. and 550 ° C., more preferably between about 425 ° C. and 510 ° C., between 0 and about 10, preferably between about 0.1 and 5, and more preferably between about 0.1 and 5. 0.1 to 1 molar ratio of hydrogen to toluene, about 1
Including the use of pressures between atmospheric and 100 atmospheres, and between about 0.5 and 50 WHSV.

The disproportionation process can be performed as a batch, semi-continuous, or continuous operation using a fixed or moving bed catalyst system placed in the reaction bed. After deactivation by coke, the catalyst can be regenerated by burning the coke to a desired extent under an oxygen-containing atmosphere at elevated temperatures, as is known in the art.

The zeolite-bound zeolite of the present invention also comprises C₈One or more in the aromatic feed
Ortho-, meta-, and xylene isomers in a ratio approaching the equilibrium value by isomerization
It finds particular use as a catalyst in processes for obtaining para-xylene.
In particular, xylene isomerization is combined with a separation process to produce para-xylene.
Used in combination. For example, mixed C₈Part of para-xylene in aromatic stream
Uses methods known in the art, for example, crystallization, adsorption, etc.
Can be collected. The resulting stream is then reacted under xylene isomerization conditions.
To restore ortho-, meta-, and para-xylene to near equilibrium ratios
. Ethylbenzene in the feed is removed from the stream or
Or benzene, which can be easily separated by distillation. Isomer
The isomerate is blended with the new feed and combined
The separated stream is distilled to remove heavy and light by-products. The resulting C ₈ The aromatic stream is then recycled to repeat the cycle.

It is important that the xylene isomerization catalyst produce a near equilibrium mixture of xylenes, and it is also usually desirable that the catalyst convert ethylbenzene with little net loss of xylenes. Zeolite-bound zeolite catalysts find particular use in this regard. Acidity of zeolite, for example, oxide of trivalent metal of silica in zeolite core crystal (alumina, gallium, boron oxide, iron oxide, etc.)
The molar ratio to can be selected to balance isomerization of xylene and dealkylation of ethylbenzene while minimizing undesirable side reactions. This process, the C ₈ aromatic stream containing one or more xylene isomers or ethylbenzene or a mixture thereof, is carried out by contacting the zeolite bound zeolite xylene isomerization / EB conversion conditions. Preferably at least 30%
Of ethylbenzene is converted.

In the vapor phase, suitable isomerization conditions are from 250 ° C. to 600 ° C., preferably 30 ° C.
Temperature in the range of 0 ° C. to 550 ° C., 0.5 to 50 atm (absolute), preferably 10 to
It includes a pressure in the range of 25 atmospheres (absolute) and a weight hourly space velocity (WHSV) in the range of 0.1 to 100, preferably 0.5 to 50. If desired, the isomerization in the vapor phase is carried out in the presence of 3.0 to 30.0 moles of hydrogen per mole of alkylbenzene. If hydrogen is used, the metal component of the catalyst is preferably from 0.1 to of a hydrogenation / dehydrogenation component selected from Group VIII of the Periodic Table of the Elements, especially platinum, palladium or nickel. 2.0% by weight. By Group VIII metal component is meant metals and their compounds such as oxides and sulfides.

The zeolite-bound zeolite catalysts of the present invention degrade naphtha feeds, such as C ₄ ⁺ naphtha feeds, especially C ₄ 290 ° C. naphtha feeds, to lower molecular weight olefins, such as C ₂ to C It can be particularly useful as a catalyst in processes for producing olefins of ₄ , especially ethylene and propylene. Such a process preferably comprises providing the naphtha feed at 500 ° C. to about 750 ° C., more preferably 55 ° C.
The contacting is carried out at a temperature of 0 ° C. to 675 ° C., at a pressure of less than atmospheric pressure to 10 atm, but preferably at a pressure of about 1 to about 3 atm.

[0093] The zeolite-bound zeolite catalyst of the present invention is useful as a catalyst in the transalkylation of polyalkyl aromatic hydrocarbons. Examples of suitable polyalkylaromatic hydrocarbons are di-, tri-, di-, tri-, such as diethylbenzene, triethylbenzene, diethylmethylbenzene (diethyltoluene), diisopropyl-benzene, triisopropylbenzene, diisopropyltoluene, dibutylbenzene and the like.
And tetra-alkyl aromatic hydrocarbons. A preferred polyalkyl aromatic hydrocarbon is dialkyl benzene. Particularly preferred polyalkyl aromatic hydrocarbons are diisopropylbenzene and diethylbenzene.

The transalkylation process preferably comprises from about 0.5: 1 to about 50: 1,
And more preferably, it has a molar ratio of aromatic hydrocarbon to polyalkyl aromatic hydrocarbon of from about 2: 1 to about 20: 1. The reaction temperature is preferably in the range of about 340 ° C. to 500 ° C. to maintain at least a partial liquid phase, and the pressure is preferably in the range of about 344.75 kPa to about 6895 kPa (about 50 psig to 1 psi).
2,000 psig), preferably 2068.5 kPa to 4137 kPa (30
0 psig to 600 psig). Weight hourly space velocity is about 0.1
Within a range of 10 to 10.

[0095] Zeolite-bound zeolite catalysts have use in aromatization processes that convert paraffins to aromatics. Examples of suitable paraffins include aliphatic hydrocarbons containing 2 to 12 carbon atoms. Hydrocarbons can be straight-chain, open-chain or cyclic, and can be saturated or unsaturated. Examples of hydrocarbons are propane, propylene, n
-Including butane, n-butene, isobutane, isobutene, and linear, branched, and cyclic pentanes, pentenes, hexanes, and hexenes.

The aromatization conditions are a temperature of about 200 ° C. to about 700 ° C., a pressure of about 0.1 atm.
Atmospheric pressure, weight hourly space velocity (WHSV) of about 0.1 to about 400, and about 0
From about 20 to about 20 hydrogen / hydrocarbon molar ratios.

The zeolite-bound zeolite catalyst used in the aromatization process is MF
Zeolite I (for example, ZSM-5) and zeolite MEL (ZSM-11)
), And binder crystals of mesopore size, such as the MEL structure type. The catalyst preferably contains gallium or zinc. Gallium can be incorporated into the catalyst during the synthesis of the zeolite, or can be exchanged or impregnated after synthesis or otherwise incorporated into the zeolite. Preferably 0.05 to 10%, most preferably 0.1 to 2.0% by weight of gallium is associated with the zeolite-bound zeolite catalyst. Gallium can be combined with the first zeolite, the second zeolite, the third zeolite, or the fourth zeolite. Usually, zinc is incorporated into the catalyst by ion exchange and is generally present in the zeolite-bound zeolite in the amounts specified above for gallium.

[0098] Zeolite-bound zeolite catalysts have use in reactions involving aromatization and / or dehydrogenation. They are processes for the dehydrocyclization and / or isomerization of acyclic hydrocarbons, wherein the hydrocarbons are at a temperature of 370 ° C to 600 ° C, preferably 430 ° C to 550 ° C, preferably alkali Zeolite-bound zeolite catalysts having at least 90% exchangeable cations as metal ions and incorporating at least one Group VIII metal having dehydrogenation activity, for example, zeolite L and zeolite Y linked with zeolite Y May be particularly useful in a process in which at least a portion of the acyclic hydrocarbon is contacted to convert it to an aromatic hydrocarbon.

Example 1 Preparation of Zeolite-Bound Zeolite The formation of silica-bound ZSM-5 and ZSM-22 extrudates was performed as follows.

[0100]

[Table 2]

Ingredients 1 to 6 were mixed in a household mixer container for 6 minutes. Next, component 7 was added to the vessel and mixing continued for an additional 3 minutes. A thick extrudable paste was obtained. The paste was extruded into a 2 mm diameter extrudate. The extrudate was dried at room temperature for 2 hours and at 130 ° C. overnight. Next, extrusion was performed at 120 ° C. for 2 hours (heating rate was set at 0.
(5 ° C./min) and baked at 490 ° C. (heating rate is 1 ° C./min) for 16 hours. The composition of the calcined silica-bound extrudates: Zeolite: 70 wt% SiO ₂ binder: XRD analysis of 30 wt.% Green extrudates showed the presence of both MFI and TON. A halo of amorphous material was seen, indicating the presence of silica.

[0102] The extrudate was converted to a zeolite-bound zeolite as follows.

[0103]

[Table 3]

Components 2 and 3 were dissolved in Component 4 and stirred until a clear solution was obtained. In order to convert the amorphous silica to the MEL structure type, the template used for the conversion, ie, t-butyl ammonium bromide, was specifically selected. Component 1 was then added to the solution. Next, the synthetic mixture was placed in a stainless steel autoclave and heated at 150 ° C. for 80 hours (heating time was 2 hours). The molar composition of the synthesis mixture: 0.50Na was _{2 O / 0.96TBABr / 10SiO 2 /} 149H 2 O.

The extrudate is subjected to 300 until the electrical conductivity of the last wash water is less than 10 μS / cm.
Washed 5 times in ml of water and then dried at 120 ° C. overnight.

The resulting extrudate was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with the following results.

XRD: Shows excellent crystallinity, indicating the presence of the MFI structural type. No amorphous rings were seen, indicating the presence of unconverted silica. The presence of the MEL structural type was not clearly demonstrated in the presence of large amounts of MFI. The amount of TON was below the lower limit of detection.

SEM: A 10000 × micrograph (FIG. 1) shows a new formed stretched crystal (1 μm × 0.2 μm) and an original spherical MFI core crystal coated with smaller sized adhesive crystals. Showed presence.

Example 2 The silica-bound ZSM-5 and ZSM-22 extrudates prepared according to Example 1 were converted to zeolite-bound zeolites as follows.

[0110]

[Table 4]

[0111] Components 2 and 3 were dissolved in component 4 and stirred until a clear solution was obtained. In order to convert the amorphous silica to the MEL structure type, a template used for the conversion (template)
), That is, t-butylammonium bromide was specifically selected. Next, component 1 was added to the solution. The synthetic mixture was then placed in a stainless steel autoclave and
Heated at <RTIgt; 20 C </ RTI> for 20 hours (heating time was 2 hours). The molar composition of the synthetic mixture is:
0.47Na was _{2 O / 0.95TBABr / 10SiO 2 /209.5H} 2 O.

[0112] The extrudate is treated with 300 until the electrical conductivity of the last wash water is less than
Washed 5 times in ml of water and then dried at 120 ° C. overnight.

The resulting extrudates were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with the following results.

XRD: Shows excellent crystallinity, indicating the presence of MFI and TON structural types. Small amounts of amorphous rings may be present. The presence of the MEL structural type was not clearly demonstrated in the presence of large amounts of MFI.

SEM: 10000 × micrograph (FIG. 2) shows the presence of both the original core crystal and the newly formed bonded crystal. The newly formed crystal appears to grow over the MFI core crystal rather than the TONE core crystal.

Example 3 The zeolite-bound zeolite prepared according to Example 1 was used for disproportionation of toluene.

Before packing in a stainless steel reactor, 1 g of zeolite-bound zeolite was mixed with 1 g of 80-100 ultra pure silica sand. Pretreating the catalyst with hydrogen at 500 ° C.,
Subsequently, co-feed of toluene and hydrogen was performed. The total reaction pressure is 31
Control was performed at 0.3 kPa (45 psig). Partial pressure of toluene supply is 37.2 kP
a (5.4 psia), the partial pressure of hydrogen supply was 372 kPa (54 psia). The flow rate of toluene was 36.7 mmol / hour. The hydrogen flow was controlled with a Brooks mass flow controller and the toluene feed was injected with a high pressure liquid pump. In order to be able to measure the reaction rate, the differential control (differentia
The experiment was carried out under the same conditions. Kirasil DEX CP
All products were analyzed on an online HP 6890 GC equipped with a and a DBI column.

Example 4 To compare the performance of zeolite-bound zeolite catalysts, H-ZSM-5 and H-ZSM-22 catalysts were used separately for toluene disproportionation. The H-ZSM-5 catalyst has a silica to alumina molar ratio of 34 and a particle size of 0.2 to 1.0.
It contained crystals in the micron range. H-ZSM-22 had a silica to alumina molar ratio of 63 and contained crystals with an average length of 1 μm. Before packing the catalyst into a stainless steel reactor, the procedure was performed except that each catalyst was mixed with 2.5 grams of 80-100 mesh ultra-pure quartz to improve the contact between the feed and the catalyst. The test was performed using the procedure described in Example 2.

FIG. 3 shows zeolite-bound zeolite catalyst, H-ZSM-5 catalyst, and HZSM
The reaction rate of the -22 catalyst is compared graphically as a function of temperature ^-1 and shows a performance comparison of the three catalysts. Zeolite-bound zeolite catalysts have a wide range of H-
It is evident from the figure that it shows about 10 times higher reactivity than both ZSM-5 and HZSM-22 catalysts. The mechanism of toluene disproportionation has an initial hydrogenation transfer step, which is the most rate-constrained. "In the mechanism of toluene disproportionation in a zeolite environment", J. Am. Am. Chem. Soc. No. 117, 9427-9
431, 1995, in Xiong, P .; G. FIG. Rodewald and C.I. D
. Reported by Chang. One possible explanation for the high activity of the zeolite-bound zeolite catalyst is that it provides a high hydrogenation transfer rate.

[Brief description of the drawings]

FIG. 1 shows an electron micrograph of the catalyst produced in Example 1.

FIG. 2 shows an electron micrograph of the catalyst prepared in Example 2.

FIG. 3 is a graph showing the rate of reaction of a zeolite with bound zeolite and two catalysts not according to the invention as a function of temperature.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C07C 15/08 C07C 15/08 C10G 11/05 C10G 11/05 35/095 35/095 45/64 45 / 64 47/16 47/16 73/02 73/02 // C07B 61/00 300 C07B 61/00 300 (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, TZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU , ID, IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, UG, VN, YU, ZA, ZW (72) Inventor Morty Wilfred Jay Belgium, Kessel-Lobey 3010, Diestesse Steinbeek 483 (72) Inventor Martins, Macteld Maria Belgium, Boat Meerbeik Bee 3190, Bellingstraat 72 (72) Inventor Party Fe , Shaoving, USA 77573, Texas, League City, Enterprise Avenue 601, apartment 317 (72) Inventor Ansonis, MH Belgium, Hosted Bee-1981, Maniastrat 30 (72) Inventor Skoufs 4500F Term (Reference) 4G069 AA02 AA03 AA08 BA07A BA07B BA45A BC08A BC15A BC21A BC22A BC24A BC25A BC26A BC30A BC34A BC38A BC49A BC62A BC63A BC64 BCA BC66A BC74A BC75A CB25 CB41 CB42 CB43 CB62 CC04 CC05 CC06 CC07 CC08 CC10 CC11 CC14 EC12X ZA04A ZA04B ZA06A ZA06B ZA08A ZA08B ZA11A ZA11B ZA12A ZA12B ZA13A ZA16A ZA16B ZA19A ZA19B ZA21A ZA21B ZA23A ZA25A ZA32A ZA32B ZA36A ZA36B ZA39A ZA41A ZA43B ZA45A ZB09 ZC06 ZC07 ZD09 ZD10 ZE03 ZF01A ZF01B ZF02A ZF02B ZF05A ZF05B 4G073 BD15 CZ48 CZ49 CZ50 DZ01 FB30 UA01 4H006 AA02 AC29 BA71 BA81 BC10 DA10 4H029 CA00 DA00 4H039 CA41 CJ30

Claims (37)

[Claims] 1. A zeolite-bound zeolite catalyst that does not contain a significant amount of non-zeolitic binder, comprising: (a) a first crystal of the first zeolite and optionally a structural type of the first zeolite. A core crystal comprising a second crystal of a second zeolite having a composition, a structural type, or both; and (b) a third crystal of a third zeolite and, optionally, a structural type of the third zeolite. Comprises a binder crystal comprising a fourth crystal of a fourth zeolite having a different composition, structure type, or both, wherein a second crystal of the second zeolite, a fourth crystal of the fourth zeolite,
Or both are present in the zeolite-bound zeolite catalyst. 2. The catalyst according to claim 1, wherein the average particle size of the binder crystals is smaller than the average particle size of the core catalyst. 3. The catalyst according to claim 1, wherein the catalyst comprises the second crystals of a second zeolite and does not comprise the fourth crystals of the fourth zeolite. 4. The catalyst according to claim 1, wherein the catalyst comprises the fourth crystals of a fourth zeolite and does not comprise the second crystals of the second zeolite. 5. The catalyst according to claim 1, wherein the catalyst comprises the second crystals of a second zeolite and the fourth crystals of the fourth zeolite. 6. The catalyst according to claim 1, wherein the second zeolite has a different structure type and composition than the first zeolite. 7. The catalyst according to claim 1, wherein the fourth zeolite has a different structural type and composition than the third zeolite. 8. The catalyst according to claim 1, wherein the second crystals have an average particle size smaller than the average particle size of the first crystals. 9. The catalyst according to claim 1, wherein the binder forms an overgrowth on at least a part of the core crystals. 10. The catalyst according to any one of the preceding claims, wherein the catalyst comprises less than about 5% by weight, based on the weight of the catalyst, of a non-zeolitic binder. 11. The catalyst according to claim 1, wherein the catalyst comprises at least four zeolites, each of the four zeolites having a different composition or structure. 12. The catalyst of any one of the preceding claims, wherein the core crystals have an average particle size of greater than about 1 to 6 microns. 13. The catalyst according to any one of the preceding claims, wherein the crystals of the binder have an average particle size of 0.1 to 0.5 microns. 14. The catalyst according to any one of the preceding claims, wherein the first zeolite is a large pore zeolite or a mesopore zeolite. 15. The catalyst according to any one of the preceding claims, wherein the third zeolite is a large pore zeolite or a mesopore zeolite. 16. The structural type of the first zeolite and the third zeolite is M
AZ, BEA, MFI, MEL, MTW, EMT, MTT, HEU, FER, T
Any one of the preceding items selected from the group consisting of ON, MWW, LTL, and EUO
The catalyst according to claim. 17. The catalyst according to any one of the preceding claims, wherein the binder zeolite has a lower acidity than the core zeolite. 18. The catalyst according to any one of claims 1 to 16, wherein the binder zeolite has a higher acidity than the core zeolite. 19. The catalyst comprises a source of hydroxide ions sufficient to convert the silica-bound conjugate comprising the first crystals of the first zeolite to the conjugate silica to binder zeolite. The catalyst according to any one of the preceding claims, produced by aging at high temperature in an aqueous ionic solution. 20. The catalyst according to any one of the preceding claims, wherein the zeolite in the catalyst is gallic silicate or aluminate silicate. 21. The catalyst according to any one of the preceding claims, wherein the catalyst further comprises a catalytically active metal. 22. The catalyst according to any one of the preceding claims, wherein the zeolites present in the catalyst have the same structure. 23. A method for converting hydrocarbons, the method comprising contacting a hydrocarbon feed stream with a zeolite-bound zeolite catalyst according to any one of the preceding claims under hydrocarbon conversion conditions. Including, methods. 24. The conversion of hydrocarbons is carried out at a temperature of 100 ° C. to 760 ° C. and / or 69.6 kPa to 69640 kPa (10.1 kPag to 10.1 MPa).
g) a pressure of (0.1 to 100 atm) and / or 0.08 hours ^{-1 to} 200
^24. The method of claim 23, wherein the method is performed under conditions including hourly hourly space velocity of time- ¹ . 25. The conversion of hydrocarbons comprises hydrocarbon cracking, alkyl aromatic isomerization, toluene disproportionation, aromatic transalkylation, aromatic alkylation,
25. The method of claim 23 or 24, wherein the naphtha is selected from the group consisting of reforming naphtha to aromatics, converting paraffins and / or olefins to aromatics, cracking naphtha to light olefins, and dewaxing hydrocarbons. the method of. 26. Isomerizing a xylene isomer or a mixture of xylene isomers and a hydrocarbon feed comprising a stream of C8 aromatics comprising ethylbenzene,
A core crystal comprising, under isomerization conversion conditions, a significant amount of a non-zeolitic binder and comprising a first crystal of a first zeolite and a second crystal of a second zeolite; 26. The process according to any one of claims 23 to 25, comprising contacting the feed with a zeolite-bound zeolite catalyst comprising binder crystals comprising third crystals of zeolite 3. 27. The method according to any one of claims 23 to 26, wherein the catalyst further comprises a catalytically active metal. 28. The catalyst, the first zeolite, the second zeolite, and the third zeolite, wherein ^* BEA, MFI, MEL, MTW, EUO, MTT,
28. The method of claim 26 or 27, wherein the method is independently selected from the group consisting of FER, TON, and MOR. 29. The method according to claim 23 or 24, wherein the method for converting hydrocarbons is cracking of hydrocarbon compounds. 30. The process according to claim 23 or 24, wherein the process for converting hydrocarbons is disproportionation of toluene. 31. The method according to any one of claims 23 to 30, wherein the zeolite present in the catalyst has a mesopore size. 32. The method according to claim 30, wherein the catalyst is provided with selectivity. 33. The method of claim 32, wherein the selective catalyst comprises about 2-40% by weight coke. 34. The method of claim 32, wherein the selective catalyst comprises silicon. 35. The method according to any of claims 23 to 25, wherein the method for converting hydrocarbons comprises dehydrocyclization to form aromatic hydrocarbons and / or isomerization of acyclic hydrocarbons.
The method of claim 1. 36. The method of claim 35, wherein said catalyst further comprises at least one catalytically active transition metal. 37. The method according to claim 37, wherein the catalyst is a first crystal of a first zeolite, a second zeolite.
A binder crystal comprising a second crystal of the site and a third crystal of the third zeolite;
Wherein the first zeolite, the second zeolite, and the third zeolite comprise: ^* BEA, MFI, MEL, MTW, MWW, LTL, EUO, MTT, FER
37. The method of claim 36, wherein each is independently selected from the group consisting of: TON, and MOR.
the method of.