JPS5953213B2 - Process for producing ZSM↓-5 type zeolite in the absence of alkali metals - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides for the production of alkali metal cations and alkaline earth metal cations by production from reaction reagents containing not more than 0.04% by weight of alkali metal oxides or alkaline earth metal oxides. from a reaction mixture substantially free of ZS
The present invention relates to a method for synthesizing M-5 type zeolite.

Naturally occurring and synthetic zeolite materials have been known in the past to have catalytic abilities for various types of hydrocarbon conversion reactions.

Some of these zeolite materials, which are porous, regularly crystalline aluminosilicates, have a defined crystal structure as determined by X-ray diffraction, within which there are many small cavities. , these small cavities are interconnected by a number of even smaller slots.

These cavities and slots are precisely uniform in size within a particular zeolite material.

These pore sizes accommodate molecules of a certain size for sorption purposes, but reject larger molecules;
These materials have become commonly known as "molecular sieves" and have been used in a variety of ways to take advantage of the sorption properties of these materials.

Crystalline aluminosilicates are characterized by the presence of aluminum and silicon, with a sum of these atoms:oxygen ratio of 1:2.

The amount of aluminum present in common aluminosilicate appears to be directly related to the acidic character of the resulting product.

A low aluminum content is advantageous in order to obtain the desired low acid density for low coke formation, low aging and high stability.

Crystallization of zeolites useful as catalysts in the absence of alkali metal cations and alkaline earth metal cations is desirable in that crystallization eliminates expensive and time-consuming exchange reactions to remove metal cations. was allowed, but was previously impossible.

D, W, Breck
was founded in 1974 by John Wiley in New York City.
(In his book Zeolite Molecular Sieves, published by J. Wile, p. 304,
It is stated that systems containing alkylammonium ions require two types of bases.

Alkylammonium bases are used in almost all cases with alkali hydroxides.

In U.S. Pat. No. 3,306,922, when making zeolites such as zeolites A, It has been found to contain significant amounts of Na2O/Al2O3, typically in a Na2O/Al2O3 molar ratio of about 0.4.

After mentioning this patent, D.D.
On page 308 of his book, he states that trace amounts of sodium promote crystal nucleation of zeolites N-A and N-Y, and that the rate of crystallization appears to depend on the amount of sodium present (N- A and N-Y are each TMA
This is a simple name for zeolites A and Y made using cations).

To date, only zeolite structures with dense pores have been created by carefully excluding alkali metal cations and alkaline earth metal cations.

C. Baerlocher and D.M. Mei
er) is Helveti force, stain force, actor (Helveti force)
ca Chimica Acta) Vol. 52, p. 1853 (1969) and Vol. 53, p. 1285 (1970)
reported the synthesis of TMA-sodalite and TMA-gismondine in their two papers in 2010).

US Pat. No. 3,702,886 describes zeolite ZS
The production of M-5 is disclosed.

It is disclosed that crystallization is carried out solely from a reaction mixture containing alkali metal cations and alkaline earth metal cations, as was common for the preparation of N-A, N-X and N-Y. .

In particular, where sodium is present, the disclosure discloses a composition range in which sodium constitutes at least 5% and even as much as 80% of the monovalent cations present, with TPA (tetrapropylammonium) ions making up the remainder. There is.

A range in which sodium constitutes at least 10% of the cations is preferred.

No. 3,709,979 discloses the preparation of ZSM-11 and discloses that sodium should constitute at least 20% of the monovalent cations present.

In a preferred reaction mixture, sodium is at least 25% of these cations.

In U.S. Pat. No. 3,941,871, ZSM
A method for synthesizing a crystalline metal organic silicate having an X-ray diffraction pattern similar to that of type-5 aluminosilicate is disclosed.

It is observed in the above mentioned patents that very small amounts of alumina are found in these organosilicates.

Such aluminum impurities are caused by SiO in the silicate.
The amount is small enough so that the 2/Al2O3 molar ratio exceeds 200.

Despite the essential absence of alumina, it is again preferred that sodium is present in the reaction mixture, preferably forming at least 20% of the monovalent cations.

According to this invention, 10-3000 SiO2:A1□0
The method for producing crystalline 28M-5 type zeolite with a molar ratio of R/5102: 0.01-1.5 and a restriction index ranging from 1 to 12 is as follows: Composition of 10-1000 H20/SiO2: 5-100 0H/5in2: 0.01-1.5 (wherein R represents an organic nitrogen and/or organic phosphorus cation, at least some of which are tetrapropyl-substituted cations) a reaction mixture which is substantially free of alkali metal cations or alkaline earth metal cations due to its preparation from reaction reagents in which the content of alkali metal oxides or alkaline earth metal oxides does not exceed 0.04% by weight. It consists of synthesizing zeolite from.

The organic nitrogen cation is advantageously tetrapropylammonium or a mixture of tetrapropylammonium and tetramethylammonium, and we have observed that many syntheses result in products of unusually large crystal size when both are present. I found it.

The resulting zeolite has a silica/alumina ratio of 10 to 200 and is often suitable for obtaining ZSM-5, which has been shown to have remarkable catalytic properties by practicing this invention.

The present invention claims that ZSM-5 retains its crystallinity for long periods of time despite the presence of steam at high temperatures, which induces irreversible collapse of the framework structure of other zeolites, such as zeolites X and A. It is applicable to the production of zeolite.

Additionally, zeolites such as ZSM-5 can be reactivated by removing carbonaceous precipitates by combustion at higher than normal temperatures when they form.

Under many circumstances this class of zeolites exhibits very low coke formation and very long operating times between combustion regeneration treatments.

An important feature of the crystal structure of ZSM-5 type zeolites is that they have pores of size greater than about 5 angstroms and pore openings of very small size, such as those provided by the 10-shell ring of oxygen atoms. Entry into and exit from free space is restricted.

It should, of course, be understood that these rings are formed by the regular arrangement of tetrahedra that make up the anionic framework structure of the crystalline zeolite.

Briefly, zeolites with the preferred type of catalytic properties useful and obtainable by the process of this invention have a silica:alumina ratio of at least about 10 and a structure that provides restricted access to intracrystalline free space. It is something.

The silica:alumina ratios mentioned above can be determined by routine analysis.

This ratio is meant to represent as closely as possible the silica:alumina ratio in the rigid anionic framework structure of the zeolite crystal.

Such a catalyst (zeolite) has a larger sorption ability for normal hexane into the crystal than the sorption ability for activated condensate into the crystal.

That is, they exhibit hydrophobicity.

This hydrophobicity is considered advantageous in this invention.

The useful types of zeolites obtained in this invention are free to sorb normal hexane and have pore sizes greater than about 5 angstroms.

Additionally, the pore structure must be such that entry into the crystal is restricted for larger molecules.

Whether such restricted access exists can sometimes be determined from known crystal structures.

For example, if only the openings of the pores in the crystal are formed by eight shell rings of oxygen atoms, entry into the pores by molecules with a larger cross-sectional area than normal hexane is excluded, so this zeolite can be of the desired type. It doesn't belong to.

Ten-ring openings are preferred; in some cases temperature shrinkage or pore clogging may render these zeolites catalytically ineffective.

The 12-shell ring generally does not appear to provide sufficient restriction to produce a favorable conversion reaction, but is of a contracted structure, such as the known effective zeolite, TMA offretite.

It is also possible to consider structures that can be used due to pore blockage or other causes.

Instead of determining from the crystal structure whether the catalyst (zeolite) has the necessary restricted pore penetration, an equal weight mixture of n-hexane and 3-methylpentane can be added to approximately 1 g of the zeolite (catalyst) or A simple determination of the restriction index can be made by flowing continuously over smaller samples at atmospheric pressure according to the procedure below.

That is, the catalyst (zeolite) in the form of pellets or extrudates is ground to approximately the particle size of coarse sand and placed in a glass tube.

The catalyst (zeolite) was heated to 538°C (1000'F) before testing.
) for at least 15 minutes with a stream of air.

The catalyst (zeolite) was then washed with helium and heated at 288°C to 510°C (550°F to 950°F) to obtain an overall conversion of 10% to 60% of the mixture of hydrocarbons.
) to adjust the temperature.

Dilute the above hydrocarbon mixture with helium:
A helium diluted mixture with a molar ratio of total hydrocarbons of 4:1 is passed over the catalyst (zeolite) at a liquid hourly space velocity of 1 [i.e., 1 volume of liquid hydrocarbon per volume of catalyst (zeolite) per hour]. .

After 20 minutes of flow, samples of the effluent were taken and analyzed, most conveniently by gas chromatographic analysis, to determine the proportion remaining unchanged for each of the two hydrocarbons.

The restriction index is calculated as follows.

The restriction index approximates the cracking rate constant ratio of the two types of hydrocarbons.

Zeolite (catalyst) suitable for obtaining by the method of this invention
is a zeolite with a restriction index roughly in the range of 1-12.

The constraints index (CI) for some representative zeolites or catalysts are as follows.

Catalyst CIZS
M-58,3 ZSM-118,7 ZSM-122 Beta 0.6
ZSM-40,5 H-Zeolon 0.5R
EY O, 4
Amorphous Silica-Alumina 0.6 Erionite 38 The Restriction Index values listed above are representative of characterizing a particular zeolite; however, Restriction Index values are the cumulative effect of several variables used in their determination and calculation. Please understand that this is a result.

288°C for the given zeolite which is
The restriction index varies within the approximate range of 1 to 12 mentioned above, with conversions associated with temperatures of 10% to 60% within the above mentioned temperature range of 510°C (550T to 950°F).

Other variables such as the crystal size of the zeolite, possible encapsulated contaminants and the presence of binders that are tightly bound to the zeolite also affect the restriction index.

The limit index used here therefore provides a highly useful means of characterizing the zeolite in question, but, taking into account the way it is determined, it is probably only an approximation combined with variable limit values in some cases. There might be.

However, in all cases the 288°C to 5°C specified above
At temperatures within the range of 10°C (550°F to 950°F), the limit index is 1 for the zeolite in question.
It is within the approximate range of ~12.

The details of the zeolite structure of ZSM-5 are described in US Pat. No. 3,702,886.

Certain zeolites mentioned above are catalytically inactive when made in the presence of organic cations.

This is probably because the free space within the crystal is occupied by organic cations from the crystal forming solution.

However, they can be activated simply by calcination to at least about 300° C., preferably in air.

Zeolites can be used in various cationic forms such as ammonium form, hydrogen form or other monovalent or polyvalent cationic forms.

Preferably, one or the other of the last two forms is used.

They also include tungsten, vanadium, molybdenum,
They can be used in close combination with hydrogenation components such as rhenium, nickel, cobalt, chromium, manganese or noble metals such as platinum or palladium, which in this case perform the hydrogenation-dehydrogenation function.

Such components can be combined by ion exchange, impregnation, or intimate physical mixing into the composition.

Such components can be impregnated onto or into the zeolite or catalyst obtained according to the invention, for example by treating the zeolite with platinum metal-containing ions.

Suitable platinum compounds that can be used include secondary chloroplatinic acid, primary chlorinated platinum, and a variety of compounds, including also shinkin-amine complex compounds.

Compounds of platinum or other useful metals can be divided into compounds in which the metal is present in the cation of the compound and compounds in which the metal is present in the anion of the compound.

Both types containing metals in ionic form can be used.

If the platinum metal is in the form of a cation or a cation complex, e.g. Pt
A solution that is (NH3)6C14 is particularly useful.

In some hydrocarbon conversion processes, such as low temperature, liquid phase ortho-xylene isomerization processes, this noble metal form of catalyst is not required.

The zeolite when used as an adsorbent or as a catalyst in one of the operations mentioned above must be at least partially dehydrated.

It is 200°C to 600°C for 1 to 48 hours under atmospheric pressure or subatmospheric pressure in an atmosphere such as air, nitrogen, etc.
This is done by heating to a temperature in the range of .

Dehydration can also be carried out at lower temperatures by placing the catalyst under vacuum, but in this case longer times are required to obtain a sufficient amount of dehydration.

Zeolites meeting the above criteria have been found to work with a variety of feedstocks to maximize the production of gasoline boiling range hydrocarbon products.

According to the method of the invention, the above-mentioned zeolite is preferably prepared from a reaction mixture having the following composition in molar ratio:

Typical reaction conditions are about 0°C to about 200°C for the mixture described above.
for about 4 hours to about 30 days.

In the case of ZSM-5 aluminosilicate zeolite synthesis, the gel particles are aged until the crystalline zeolite is completely formed.

The product crystals are then separated, for example by cooling, filtered, washed with water and dried at about 0°C to about 150°C.

Zeolites synthesized by the method of this invention can have a variety of other ions associated with them by ion exchange techniques well known to those skilled in the art.

Typical cations are metal cations, including hydrogen, ammonium, and mixtures.

Particularly preferred metal cations are rare earth metals, metals such as manganese and calcium, especially metals from group 1I of the periodic table, such as zinc and metals from group Vll of the periodic table.
It is a cation of a group I metal such as nickel.

As with many catalysts, it is desirable to combine the zeolites (catalysts) obtained from this invention with other materials that are resistant to the temperatures and other conditions used in organic conversion processes.

Such materials include active and inert materials and synthetic or naturally occurring zeolites and inorganic materials such as clays, silicas and/or metal oxides.

The latter may be of natural origin or in the form of a gel-like precipitate or a gel containing a mixture of silica and metal oxides.

Zeolite (catalyst) obtained by the method of this invention
The use of other materials in combination with the catalyst tends to improve the conversion and/or selectivity of the catalyst in certain organic conversion processes.

The inert substance controls the amount of conversion in a given conversion process,
As a result, it serves reasonably well as a diluent so that the product can be obtained economically and regularly without taking other measures to control the reaction rate.

Zeolites are commonly incorporated into naturally occurring clays such as bentonite and kaolin to improve the crush strength of the catalyst under industrial operating conditions.

These materials, clays, oxides, etc., act as binders for the catalyst.

It is desirable to provide a catalyst with good crushing strength since catalysts are often subjected to rough handling in petroleum refining processing, which tends to fracture the catalyst into powdered material and cause problems during processing.

Clay binders have been used to improve the crush strength of catalysts.

Naturally occurring clays that can be composited with catalysts include montmorillonite and kaolin systems, including subbentonite and commonly known kaolin or base minerals such as texie, McNamee-Georgia and Florida clays. Includes other clays whose constituents are halloysite, kaolinite, teitzite, nakelite or anauxisite.

Such clays can be used in their raw, as-mined state or after first being subjected to calcining, acid treatment or chemical modification treatments.

In addition to the above-mentioned substances, catalysts may include alumina, silica, silica-alumina, silica-magnesia, silica-zirconia, silica-thoria, silica-beryria, silica-titania, especially silica-alumina-thoria, silica-alumina-zirconia, silica Can be composited with porous materials such as ternary compositions such as alumina-magnesia and silica-magnesia-zirconia.

The matrix may be in the form of a kogel.

The relative proportions of finely divided crystalline aluminosilicate containing an aluminum undoubled shell and inorganic oxide gel matrix vary over a wide range with respect to crystalline aluminosilicate content from about 1% to about 90% by weight of the composite, and more commonly from about 2% to about 50% by weight of the composite when the composite is formed under a via.
range.

Using catalysts containing zeolites according to the process of this invention containing a hydrogenation component, petroleum heavy residues, recycle oils, and other hydrocrackable feedstocks can be converted to hydrogen to hydrocarbons ranging from 2 to 80%. 204℃~455 using raw material molar ratio
Can be hydrogenolyzed at temperatures below 400°F and 850°C.

The pressure used varies from 0.7 to 175 kg/cm'' gauge pressure (10 to 2500 psig) and the liquid hourly space velocity varies from 0.1 to 10.

Catalytic cracking catalysts comprising crystalline zeolites obtained by the process of this invention allow hydrocarbon cracking feedstocks to be heated at liquid hourly space velocities of 0.5 to 50, about 2
Cracking can be carried out at temperatures of 88°C to 704°C (550°F to 1300'F) and pressures of about atmospheric pressure to 100 atmospheres.

When using the catalytically active form of zeolite obtained by the process of this invention containing a hydrogenation component, the reforming feedstock can be heated from 371°C to 538°C (700°F to 1
It can be modified at temperatures as high as 0.000°F.

Pressure is 7~70kg/cm2 gauge pressure (100~1
01000 pSi, but 14~
49kg/crn2 gauge pressure (200~700ps
ig) is preferred.

The liquid hourly space velocity is generally between 0.1 and 10, preferably 0.
5 to 4, and the hydrogen:hydrocarbon molar ratio is generally 1 to 20, preferably 4 to 12.

Catalysts using zeolites obtained by the process of this invention can be used for the hydroisomerization of normal paraffins if a hydrogenation component, for example 1 gold, is provided.

Hydroisomerization is from 93°C to 371°C (200°F to 7o).
'F), preferably 149°C to 288°C (300°F to 5
50 below), 0.1-2, preferably 0.25-0.
It can be carried out using hydrogen at a liquid hourly space velocity of 50 and a hydrogen:hydrocarbon molar ratio of 1:1 to 5:1.

Further, the catalyst using the zeolite obtained by the method of the present invention has a temperature range of -1.1°C to 260°C (30°F to 500°C).
Temperature F) can be used for isomerization of olefins.

Catalysts using the zeolites obtained according to the invention, containing metals such as gold, can also accomplish other reactions, including hydrogenation-dehydrogenation reactions and desulfurization reactions.

This invention will be explained below with examples, all gels are 510299.6%, Al2030.03% and Na
Made from silica gel containing 200.04%.

TPA·OH (tetrapropylammonium hydroxide) was made from TPA-Br and Ag2O.

Aluminum can be used as Al2(SO4)3 .16H20, as aluminum grains, or as AI.

It was added as 03.3H20.

Example 1 7.1 g of silica gel, 25% in a Teflon bottle
A1□(SO4)3 ・16H2 in 49 g of H2O to a mixture of 34.7 g of TPA-OH and 17.7 g of H2O
A solution of 1.5 g of TPA-Br and 4 g of TPA-Br was added.

The bottle was placed in an autoclave and kept at 160°C for 4 hours.

The obtained crystals were filtered and dried to obtain 6.1 g of a substance identified as ZSM-5 (zeolite) with 100% crystallinity.

The properties of the reaction mixture and products are listed in the table below.

Examples 2 to 4 TMA (added as hydroxide, chloride or bromide)
The procedure of Example 1 was repeated 3 times with the addition of 10% of the reaction mixture of Examples 2 and 3.

The properties of the reaction mixture and products are listed in the table below.

Typical operations for the synthesis of ZSM-5 (zeolite), particularly in the presence of alkali metal cations in the reaction mixture, usually yield crystals of about 0.2 micron size.

The products of Examples 1 and 4 are about 0.5 x 1.0 micron in size, and the products of Examples 2 and 3 are about 4 x 20 microns in size.
The crystal size is microns.

This invention thus provides a method for using zeolites for use as catalysts in processes known to be more effective when the zeolites are of relatively large crystal size, particularly embodiments of the invention where more than one organic cation is present. It has notable uses in synthesis.

Claims (1)

[Claims] 1 The following composition expressed in molar ratio: R/SiO2: 0.01-1.5 SiO2/A1□03: 10-1000 H20/5102: 5-100 0H/5in2: 0.01 ~1.5 (wherein R represents an organic nitrogen and/or organic phosphorus cation, at least some of which are tetrapropyl-substituted cations). 10-3 consisting of synthesizing a zeolite from a reaction mixture substantially free of alkali metal cations or alkaline earth metal cations by preparation from not more than 0.04% by weight of the reaction reagents.
It has a SiO2:Al2O3 ratio of 000 and a restriction index of 1.
A method for producing a crystalline zeolite consisting of zeolite l-ZSM-5, which is 12. 2. The method of claim 1, wherein the reaction mixture contains both tetrapropylammonium cations and tetramethylammonium cations. 3. A method according to claim 1 or 2, wherein the zeolite has a silica/alumina ratio of 10 to 200. 4. A patent claim in which the reaction mixture has the following composition: R/5102: 0.01-1.5 SiO2/A1□03: 10-200 H20/SiO2: 5-100 0H/5in2: 0.01-1.5 The method according to any one of items 1 to 3. 5 A patent in which the reaction mixture has the following composition: R/5102: 0.05-0.8 SiO2/A1□03: 20-150 H20/SiO2: 10-70 0H-/SiO2: 0.05-0.8 A method according to any one of claims 1 to 4. 6. A patent claim in which the reaction mixture has the following composition: R/SiO2: 0.1-0.4 SiO2/A1°03: 30-100 H20/SiO2: 20-50 0H/5in2: 0.1-0.4 The method according to any one of items 1 to 5.