DE2026393A1 - Process for the production of active silicic acid and active silicates and the use of these compounds for the production of zeolites - Google Patents

Description

DIPL-CHEM. DR. ELISABETH JUNG DIPL-CHEM. DR. VOLKER VOSSIUS DIPL-PHYS. DR. JÖRGEN SCHIRDEWAHN

PATENT LAWYERS

P 287 C
y / k

2 May 9, 1978

8 MONKS 23.

CLEMENSSTRASSE 30 ■

TELEPHONE 345067 TELEGRAM ADDRESS: INVENT / MONCHEN TELEX 5-29 686

LAPORTE INDUSTRIES LIMITED, London, Great Britain

^H process for the production of active silica and

active silicates and use of these compounds _: for the production of zeolites "

Priority:
Registration no.

29 May 1969, Great Britain 27 152

The present invention relates to an improved method for the production of "active" silica and "active" silicates and their use for the production of zeolites.

In the patent application P 16 67 710.4-41 "active" pebbles are acid and "active" silicates of the general Foi'mel 'η Ka "OiSiO tx ₉ H ₉ O described in which a eii? In value by, O bie less ale 0.5 and χ has a value of mefa 4s O ₅ 1.

009849/1719. _BATH

In addition, in this patent application, processes for production such silicas and silicates and their use for the production of special crystalline synthetic Zeolites described. The term "active" is used in the context of the above-mentioned patent application and in the context of the invention understood a special and previously inexplicable catalytic effect in relation to that reaction, which takes place in the production of a zeolite.

In British patent application 1,081,131 and in US Pat British patents 1,145,995 and 1,171,463 will use it special "active" metasilicate hydrates for manufacture crystalline zeolites, especially zeolite A and synthetic faujasites. The manufacture of such active metasilicate hydrates and other specifically listed active silicic acid compounds is used in the UK Patent 1,171,462 or in patent application P 16 67 729 * 5-41. The term "active" used here must be complete clearly distinguished from the term "activated" commonly used in the technical field of silica compounds will. In accordance with the procedures common in the field of silicon compounds, a silica gel is becoming more common Density (compare the Encyclopedia of Chemical Technology by Kirk-Othmer, Interscience, 2 »edition, volume 18, pages 63 65) with a large internal surface made by combining sodium silicate with a strong mineral acid Silica hydrosol converts this hydrosol to a gel, because the hydrogel mass breaks up mechanically,

009849/1719

washes out and then thermally "activated" ^11. With such a silica gel of the usual density, the maximum "activation" is achieved when the water content has been reduced to about 6% by weight. In such a state, the absorption capacity of the gel reaches a maximum. Such an “activated !?” silica gel, however, does not have the special catalytic effects which have been pointed out above.

With the exception of the special catalytic effect in relation to the zeolite formation reactions could not distinguish between "active" silicic acid compounds in the Sinue of the invention and other compounds of the same chemical composition. Neither became a difference there is another difference in terms of chemical composition with regard to physical properties by means of infrared, spectroscopy (disk made of KBr), electron microscopy and therihogravi metric analysis established. The powder X-ray diffraction patterns are yellow show no difference at all between an "active" sodium silicate hydrate or silica conventional type. In Fig. 1, an infrared spectrogram is a "Active" sodium metasilicate pentahydrate having an activity rating of 100 as defined below reproduced and Pig. 2 shows a corresponding infrared spectrum. it is sodium metasilicate pentahydrate with an activity rating of 0. As a result of this lack of any distinction, it is necessary to re the different behavior with regard to the Seolith

00S848 / 17?

BATH ORIGINAL

to use the educational response by means of an activity test, in order to be able to differentiate between "active" and other forms of a special silicic acid-containing compound.

A possible explanation for this different behavior could be, for example, that there is a balance between a real metasilicate, for example, and a acidic orthosilicate as represented by the equation below

HO ONa ONa

Si XH _o 0 ^ Z ± 0 = Si (X + 1) H ₉ O

HO ONa ONa

In all of the manufacturing processes given in the present description, which deviate very clearly from the usual procedures, the equilibrium on the "active" side seems to be frozen. In this connection it has been observed that when an "active" material is melted and subsequently solidified, a material that is practically completely inactive is obtained just below the melting point. If one melts a non-active material, however, this subcooled, and then holding at a temperature at least 15 ⁰ C below the melting point, bo obtained crystals of an "active" form.

Such an "active" hydrated sodium precipitate can, for example, consist of a sodium allicate nit tintm ftolar «n Vtr-

009849/171

NapO / SiOp ratio in the range from 0.5 to 1.5 can be obtained by treating the silicate with liquid water or steam. In a known procedure for the production of an "active" sodium silicate _{hydrate, an aqueous solution of a sodium silicate with a molar ratio Na 2} O / SiOp of 0.5 to 1.5 and sufficient water for the production of the desired hydrate is supercooled and then the hydrate crystallizes out of the supercooled solution at a temperature which is during the crystallization process in the range of 15 ⁰ G up to a temperature 15 ⁰ C below the melting point of the respective hydrate. A preferred crystallization temperature is in the range from 20 to 30 ^° C. The aqueous solution of sodium silicate in question can be prepared from a previously prepared sodium silicate itself, or appropriate amounts of sodium hydroxide and a silicate or silica are used, so that the molar ratio of Na ₂ O / SiO _{2 of} the starting solution corresponds to that which is required for the formation of the desired "active" sodium silicate hydrate. Crystallization can be initiated by inoculating the sodium silicate solution with a solid sodium silicate hydrate. In a modified method for producing such an "active" sodium silicate hydrate, solid crystallization of the hydrate from the aqueous phase is carried out in the temperature range specified above. These crystallization methods are particularly applicable when active sodium metalate hydrates are produced with 4 or more moles of water per mole of metalate. Such "active" sodium-

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However, silicate hydrates can also be obtained by bringing a solid, sodium silicate into contact with water vapor and keeping the temperature in the range from 0 to 60 ^° C. during the hydration process. This procedure is particularly recommended when "active" hydrated sodium metasilicates are to be produced which contain less than 4 moles of water per mole of metasilicate. Further details of this hydration process are described in British Patent 1,171,462. In these hydration methods, however, the stated temperature ranges are critical if one wishes to produce an "active" material and, in general, it is necessary to take care to remove the amount of heat released during hydration so that the temperature does not exceed the stated upper limits increases. The heat released can be removed very easily by carrying out the crystallization process of the hydrate in the presence of an inert liquid diluent, the term "inert" being understood here to mean that the diluent does not change with the silicate.,. De ⁸ molar ratio Na ^ O / SiOp reacts.

Further details of this process are in the patent application P 16 67 729.5-41 described.

Such an "active" silica-containing compound has, inter alia, the following advantages:

a) The reaction rates are much greater at a given temperature than at an inactive one

Material;

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_7_ 20263.13

b) Products of a higher degree of purity are obtained;

c) in the production of zeolite X no longer aging treatments are required and also for the production No aging treatments are necessary for zeolite Y, in contrast to the previously known Manufacturing processes as described, for example, in US Pat. No. 3,130,007;

d) the problems associated with mechanical and thermal movement of the reaction solution do not arise on how Bo, for example, in relation to the manufacture of Zeolite X in British Patent 973,933 and relating to the preparation of Zeolite Y in US Pat U.S. Patent 3,130,007.

As has already been explained above, such a% "Active" siliceous compound only with respect to their effect in the manufacture of zeolite from a non-material differ and therefore become the following

Test method used to determine activity »■ ™

Eb a reaction mixture is prepared, which the individual contains components in the following molar ratios:

= 47.00

SiO ₂ 3 .85, Na ₂ O = 1 , 34, H ₂ O Al ₂ O, SiO ₂ Well ₂

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The silica-containing component of the reaction mixture consists of the compound to be tested. The aluminum oxide component consists of sodium aluminate. The NagO component consists of the sodium cation of the silicate and the aluminate and if additional amounts of sodium cation are required are, 'this is added in the form of sodium hydroxide.

This reaction mixture is heated to a temperature of 90 to 100 ^° C. and then refluxed for three hours at this temperature with vigorous stirring. The forming product is separated from the reaction mixture, dried to form a filtrate having a pH value of about 10 and then washed at 80 to 100 ⁰ C. The percentage of zeolite X in this reaction product is then determined by comparing the X-ray powder diffraction diagram with a diagram of standard samples which contain known amounts of zeolite X, the remaining proportion in each standard sample consisting of zeolite B and / or zeolite C.

Preferably the silica-containing compound to be tested and any additionally required sodium hydroxide dissolved in about half the required amount of water. The sodium aluminate is then slowly added to this solution while stirring and the rest of the water added. The reaction mixture so prepared is stirred vigorously for 10 minutes to ensure that the mixture is in fact is homogeneous. The method is expedient with amounts of

00984 9- / 1719

Reaction mixture carried out between 50 g and 500 g. Only a silicic acid-containing compound which gives a reaction product under the conditions described above, which is practically completely pure zeolite X, i.e. a product which contains 98 to 100% by weight of zeolite X, is referred to as "active" in the context of the present invention. ·. .

It has also been shown that such "active" silicic acid-containing Compounds have the property of catalytically influencing the zeolite formation reaction in different ways Have extent. This differential effect can be measured by means of the activity rating, which is a is an arbitrary number, which is based on the content in percent by weight of zeolite X, which in a series of various tests in the solid products obtained thereby. .

The first test is that test which has been described above and enables a determination of whether a silica-containing compound is "active" or not, in which case the compound to be tested provides all of the silica-containing component in the reaction mixture. The second and subsequent tests of the series will be carried out under the same conditions as the first test, however, the siliceous test .The compound is the pros in smaller and smaller shares in total in the Esalrfcieiiiesnieohung? existing silicic acid-containing component v <5rte '' nd9t _s where'-der

009849/1719

The remaining proportion is then a silicate with an activity rating of O is "b and a commercially available sodium disilicate is used for this purpose. Such a commercially available sodium _{disilicate has approximately the composition Na 3} O.2.1 SiO ₂ * 14.1 H ₂ O.

The series of tests is given in Table I below.

Table I.

.Test no.

1 2

4 5

^ Proportion (SiO ₂ * mol) of the silica-containing compound to be tested, based on the total content of silica in the reaction mixture

100 '10 1

0.1 0.01

During the practical implementation, the silica-containing compound, any test of the above series performed including the test in which practically no more pure zeolite X is formed =

In these tests, too, the amount of reaction mixture is expediently 50 g to 500 g

Depending on the result achieved in © in © m pair won Teeta

0O9849 / 171S

- U-

Table I assigns these to an activity rating which is shown in Table II below.

Table II '

By weight of zeolite X in the reaction

Activity evaluation product (remainder: zeolite B and / or

Zeolite C)

Test 1 Test 2 Test 3 Test 4 Test 5

0 <1.

10 98-100 & <70

100 ₍ 98-100 &<60

1000 98-100 & <50

10000 > 98-100 &<50

For the evaluation of the activity between the individual powers of ten, a linear relationship is assumed between the evaluation units themselves and the percentage content of zeolite X in the reaction product. For example, if an "active" silica ^ acidic compound in the first test substantially pure zeolite X supplier and in the second test, a product which contains zeolite X in the range of about 70 to wexiiger than 98 i », and which, therefore, an activity rating in Range from 10 to 100 units then the actual activity rating will be Bzaiij. üTitles calculated according to the following relationship:

• Activity rating "= 10 + 90 ($ Zeolite X in the product -70 $).

5o '009849 / 171- /

BAD ORDINAL

Accordingly, the activity rating for an active Silica-containing compound, which was practical in test # 2 pure zeolite X and in test no. 3 a product with a content of zeolite X in the range from $ 60 to $ 98 and which therefore has an activity rating between 100 and 1000 units, calculated according to the following relationship:

"Activity rating = 100 + 900 (# Zeolite X in the product -

Activity rating numbers that are between the higher potencies of 10 are calculated in the same way.

An "active" silica-containing compound within the meaning of the invention is therefore one which, in the first activity test, yields a product with a zeolite X content of about 98 to 100% by weight, and which therefore has an activity rating of at least 10. For most practical purposes, an activity score of 10 units is the lower limit. An inactive material which in the first activity test delivers a reaction product with a content of less than 1% by weight of zeolite X accordingly receives the activity rating 0. For a material which in the first activity test a product with a zeolite X content between about 1 and 98 io , the activity rating would be calculated by dividing the percentage of zeolite X by 10.

Although the activity above in relation to the elucidation of ^; Zeolite X has been explained and this catalytic effect

0090 ^ 9 / 17-1 9

is also used for the evaluation of the activity, but all of the substances designated as "active" also have the corresponding ones Advantages in making a very large number of others synthetic zeolites, for example in the production of zeolite A, X and Y.

British patent application 1 193 254 describes a process for the preparation of "active" silica-containing compounds of the general formula η Na ₂ O: SiOg: x H ₂ O, where η has a value in the range from 0 to less than 0.5 and | χ has a value of more than 0.1, where "active" silica or an "active" silicate of the general formula (NapO): SiOp s y HpO, in which m has a value of 0.5 to 1.5 and y is one Has a value of more than 0.05, is treated with a strong acid, for example hydrochloric acid or nitric acid, and the temperature is kept in the range of 60 ⁰ C or lower, and in this way the sodium cation is at least partially removed. In this known procedure, large amounts of heat are released, and it is therefore necessary to provide means to this heat abzule'iten and keep the Reaktionsteraperatur below 60 ⁰ C, otherwise enter a Desakfcivierung.

Surprisingly, it has been shown that it is possible

such '♦ active ¹¹ silicic acid-containing compounds of the general formula η NagO: SiO ₂ : x H ₂ O, in which η has a value Ton 0 to less than 0.5 and χ has a value of more than 0.05, without the temperature -dee-reaction-

009849/1719

mediums must be kept below 60 ^{0 C.} In this way the risk of producing deactivated silica or deactivated silicates can be avoided, and it is also easier to produce crystalline synthetic zeolites by using such an "active" silicate or such an "active" silica in the aqueous aluminosilicate reaction mixture .

The inventive method for the preparation of "active" silica and "active" silicates of. general formula η NagO: SiO ₂ : x H ₂ O, in which η has a value from 0 to less than 0.5 and X has a value of more than 0.05, preferably of at least 0.1, through partial or complete Removal of the cation from an "active" sodium silicate _{hydrate of the general formula m Na 2} O s SiOg J y H ₂ O, in which m has a value from 0.5 to 1.5 and y has a value above Oj 05-, is thereby- in that the "active" Natriumsilikathydrat with the salt of a non-metallic base having a pK, of from 2.0 to 9.0, or with a weak acid, having a _pK value from 5.0 to 9.0 on-

umgesot '/. t V7ird. * ..

HasV, "SalPie of nitrogen-containing bases are particularly suitable for the process of the invention. Examples of nitrogen-containing bases with a pK ^ value in the range from 2.0 to 9.0 are aliphatic amines, such as mono-, di- and trimethylamine and- Afchylamine _s heterocyclic compounds with a heterocyclic nitrogen atom, such as pyridine, piperidine and ghitioline, as well as hydroxylamine and ammonium hydroxide In general, salts of weak or strong acids can be used

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can be used, for example chlorides, sulfates, nitrates or carbonates of the base in question. For example, can the hydrochlorides of hydroxylamine or the aforementioned aliphatic amines and heterocyclic compounds .used will. However, preference is given to ammonium salts, in particular ammonium chloride, ammonium sulfate, ammonium nitrate and Ammonium carbonate.

From the series of weak acids with a pK value in the range from 5.0 to 9.0, carbonic acid is particularly preferred.

The "active" sodium silicate can be treated with the salt of a base or with a weak acid in an aqueous medium. For example, the salt of a base or the weak acid. each preferably in the form of an aqueous solution, to an aqueous solution of the "active" sodium silicate in question, in an amount sufficient to precipitate at least part or even the total amount of the silica content present in the active silicate, which of the Proportion of the cation depends on which ' M is to be removed. If carbonic acid is used as the weak acid, the silica content of the "active" sodium silicate can also be precipitated by simply bubbling carbonic acid through an aqueous solution of the active sodium silicate in question. According to another and preferred formulation, the required amount of an aqueous solution of the "active" sodium silicate in question becomes an aqueous solution of the weak acid or the salt of a Bane '-. XgvBeivA. (! u Π B /. fj / * 7 1 9

original

The concentrations of the aqueous solutions used are not critical. The aqueous solutions concerned can each contain, for example, 1 to 5 gram mol per liter of the sodium silicate starting material or the weak acid or the salt of a base.

The reaction is expediently carried out at room temperature, ie at a temperature in the range from 10 to 30 ^° C., however, if desired, higher temperatures up to about 100 ^° C. can also be used.

The silica-containing material precipitated by the treatment described above can be ^{separated from the aqueous medium 1} in any desired manner, for example by filtration. The precipitate can then be washed with a

suitable solvents from entrained fractions of the sodium salts, .from free base or other impurities. The content of entrained salts in the precipitate is preferably reduced to a value of less than 2% by weight. The silica-containing product purified in this way can then be dried ^{at a temperature of 15 to 35 ° C.}

however, higher temperatures up to about 100 ^° C. can also be used for this purpose. Temperatures well over half 100 ⁰ C, however, should be avoided, otherwise reducing the activity of evaluation may siliceous product occur.

A particular advantage of the inventive process loading, \ is the fact that no significant amounts of heat released

0 0 9 8 A 9/1 7 1 9

will. While it is essential in the process of British patent application T 193 ² 54 to keep the temperature of the reaction medium below 60 ° C. in order to avoid deactivation of the product formed, in the process according to the invention there is practically no reduction in the activity rating, even if a temperature of '75 ⁰ C is used.

The weak acids and the salts of bases with the prescribed pK or pK _b values have the ability to precipitate the silica content from the sodium silicate solution without releasing significant amounts of heat. Salts derived from metal hydroxides with pK ^ values within the specified range, on the other hand, form the corresponding metal silicates and, for this reason, cannot be used in the context of the invention. Connections with pK, - or ¹ . pK values within

D et

the specified limit values are particularly suitable for the purposes of the invention. Therefore carbonic acid with a pK _& value of 6.37 and salts of ammonium hydroxide with a pK. Value of 4.75 are preferred. 'f

The pK and pK _fe values given here are in the "Handbook of Chemistry and Physics", 46th edition, published by The Chemical Rubber Co., 1965, on pages D77 to D79.

ι ·

purifies.

When the cation is completely or partially removed in an aqueous medium becomes ,, so the relative proportions of the individual

8 4 9/1719

nth reaction partner selected according to the extent to which the Ka: ion is to be removed from the silicic acid-containing starting material. The corresponding product is then made precipitated in the aqueous medium and, after purification, has a composition which is within the limits of the above given general formula. Palis only part of the silica content of the raw material used Sodium silicate is precipitated in an aqueous medium, the resulting silica-containing product has a higher Activity rating as the "active" sodium silicate used as the starting material. In such a case, it can be used as a Sodium silicate used as the starting material even has an activity rating number of only one unit.

According to a particular embodiment of the invention Process therefore uses an "active" sodium silicate as the starting material of the general formula given, which has an activity rating of at least one unit and only part of the total silica content is precipitated from this starting material in aqueous solution.

If, on the other hand, all of the silica content is precipitated, then there is no substantial increase in the activity rating watch. But if about a third of the silica content is precipitated, increases in the activity rating can occur in

ι 2 of the order of magnitude of about 10 to 10 can be observed.

The inventive method can be batchwise or perform continuously. 0 0 9 8 A 9/1719

An "active" silicic acid-containing product produced according to the invention Product can be used for the production of synthetic zeolites with molecular sieve and base exchange properties will. The preparation of such zeolites is already described in British patent application 1,193,254 or in German Patent application P 16 67 710.4-41 described.

According to one embodiment, the isolated "active" Silicic acid-containing product, which has preferably been purified by removing entrained salts, for the production of I ment of a zeolite reaction mixture used, which the required Proportions of the silicic acid-containing component, an aluminum oxide component, a cationic component and contains water. The zeolite is then crystallized out from such a reaction mixture under suitable conditions.

However, one produced according to the method erfindungsgernässen "active" silica-containing product does not need from the aqueous production medium to be isolated, but Λ this aqueous medium containing the active product ·, can be used directly for preparing the zeolite reaction mixture. .

A sodium silicate of the general formula, which has an activity rating of less than 10 but at least 1, can also be used for the preparation of the ^{7 "ulcers.}

Also in this case is there, "he salt e1 ^v weak acid and • '■ 003849/17,

BATH ORIGINAL

a base, preferably ammonium carbonate. If the salt is derived from ammonium hydroxide, it will be in the course of treatment Ammonia is released and removed in this way from the aqueous reaction medium.

The course of the zeolite formation reaction is determined by the presence not adversely affected by carbonate ions in the reaction mixture. This is in contrast to other anions, like Chloride and sulfate anions, which cause the zeolite formation reaction to take place adversely affect if they are present in noticeable concentrations.

The composition of zeolite reaction mixtures, expressed in the molar proportions of the oxides which are required for the production of zeolites A, X and Y, result from the following table III »

009849/1 71 9

N / A Tabel III until 4.0 0.30 until 30.0 until ! ° 5 more preferred 19th until 8th ♦ until ¹ area 0 70 Zeolite A 28 wide area until 20.0 0.31 until 6.5 until 12th 0, 85 until 7th H until 2.7. 70 . SiO ₂ Al ₂ O ₃ 30th 0.06 until 100 0.32 until until 14th 0, until 20th until 9.7. 90 Na ₂ O / SiO ₂ 31 0.7 wide area 0.335 until 16 30th more preferred 20th 200 90 H ₂ 0 / Na ₂ 0 32 15th 2.0 0.4 until 20th 2, 20th ₂ O / Na ₂ area 120 Zeolite X 335 0.4 1.0 until 40 0, 12th until 8.0 120 SiO ₂ / Al ₂ O " 4th 10 2.0 until 50
ψ 35 12th until 5.0 120 Na ₂ 0 / Si0 ₂ 0 30th 12th until 200 H ₂ 0 / Na ₂ 0 ₂ 0 / Si0 ₂ 12th until Zeolite Y until until area until 150.0 until 1. 0, until until. 2. 0, until SiO ₂ / Al, 3. 0, until 8th
* 4. 0, until • 8th 5. 0, until 8th 6. 0, 8th 7. 1, 7th 5 8th

The concentration ranges given above can be used directly if the silicic acid-containing product in question is isolated from the aqueous production solution and is then used to prepare the zeolite reaction mixture.

However, the above ranges are also applicable if dae

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Silicic acid-containing product is not isolated from the aqueous medium but used together with it directly for the preparation of the zeolite reaction mixture. In this latter case, however, the sodium component of the zeolite reaction mixture is provided by the sodium carbonate formed together with the silicic acid-containing product. Although the carbonate ion does not adversely affect the course of the zeolite formation reaction, it still masks the sodium and therefore only part of the sodium actually present is effective for the zeolite formation. This masking of the sodium makes it possible to produce zeolite reaction mixtures with relatively low molar ratios of NapO / SiOp. If carbonate ions are present in the zeolite reaction mixture, the number of effective moles of Na ₂ O in the reaction mixture can be calculated as the total amount according to the following equation

in

I and the total amount of carbonate ions in moles in the

Relate the zeolite reaction mixture:

Total amount of Na ₂ O in mol -

»Number of effective moles of Na ₂ O = 10 Total amount of carbonate ions in moles -

2 + total amount of carbonate ions in moles

From the number of effective moles Well _? 0, the molar ratio of effective Na ₂ O / Si0 _{2 is} calculated and it is this molar ratio which should be within the ranges given in Table III.

The silica component of the reaction mixture can be whole or

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partly consist of the sodium silicate concerned * and the all or only part of the silica content of the sodium silicate can be failed. Other required silica is added in the form of commercially available sodium disilicate.

The required aluminum oxide is added to the reaction mixture in the form of sodium aluminate and sodium hydroxide can serve _{as a source of additional Na 2 O «}

During the production of the zeolite reaction mixture, the Composition of the aqueous medium containing the "active" silica-containing product together with untreated Sodium silicate starting material as well as along with the precipitated Sodium carbonate formed from the silicic acid-containing product contains, adjusted so that the required molar ratios for the oxides of the reactants are obtained.

From this Zeo'lith reaction mixture of the desired zeolite is formed by holding the mixture preferably under ™ stirring at a temperature in the range of 30 to 120 ⁰ G, preferably from 80 to 120 ⁰ C, is down to the crystalline zeolite. ■

In a corresponding manner, other crystalline zeolites, for example zeolite A, X and Y, can be prepared using zeolite reaction mixtures containing the appropriate molar ratios for the oxides of the reaction part

0098 49/1719

- have 24 users.

The process according to the invention for the production of crystalline zeolites is particularly favorable when zeolites are produced should be provided which contain both sodium and potassium cations. The potassium becomes the reaction mixture expediently added in the form of potassium aluminate or potassium hydroxide, and the other measures are then the same as ■ described above. In this way, Zeolite X'M and a new Zeolite LS 102 could be produced.

The zeolite LS 102 has a composition according to the following general formula

0.7-1.3 ((1 (Na ₂ O: (1-d) K ₂ O): Al ₃ O ₅ : e SiO ₂ : f H ₂ O

in which d has a value from 0 to 1, e has a value from 6 to 8 and f has a value up to about 10. The powder X-ray diffraction diagram a typical sample of Zeolite LS 102 is given in Table VE below. For making this the composition of the new zeolite, the reaction mixture, ρ expressed in molar ratios of the oxides within the after areas indicated in the upright position are:

Table IV

SiO ₂ / Al ₂ O ₅ 15 to 30

Na ^ O η K _? 0 / Si0 ₂ 0.2 to 0.6

H ₂ 0 / Na ₂ 0 HC ₂ O. 20 to 100

rO + K ₃ O 0.1 to 0.9

0098 4 9/1719

Except for the production of zeolites, which are both sodium and also contain potassium cations, those are suitable according to the invention "active" silicic acid-containing compounds that can be produced also for the production of zeolites, which sodium together with one or more other cations of the following Type Contain: Lithium, Rubidium, Cesium, Magnesium, Strontium and barium and ammonium cations.

According to a modified method for the production of crystal

linen zeolites, the zeolite reaction mixture / the required Amounts of the aluminum oxide component, a silicic acid-containing component, which is at least partially in the form an "active" sodium silicate of those indicated above

present -

Formula contains one or more cation components and water, treated directly with carbonic acid or a salt made from carbonic acid and a base of the specified kind, so that then at least part of the silica content of the "active" sodium silicate is precipitated and, preferably after Removal of any free base present, the necessary conditions to crystallize the zeolite are maintained.

example 1

This example illustrates the production of an "active" Silicates or an active silicic acid by complete or partial removal of the cation from sodium silicates with certain activity ratings.

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Using sodium metasilicate as a starting material A series of experiments are carried out by mixing the starting material with either carbon dioxide or the salt of a nitrogenous base is treated. The conditions used and the results obtained are as follows Compiled in Table V.

-In each attempt a sodium metasilicate is used in the composition NagO: S1O2: 1 »2 H2O used to make the aqueous solution A with the specified concentration, the activity rating of the metasilicate also being given in Table V. is. In addition, an aqueous solution B is prepared which contains a salt of a nitrogenous base, and the The concentration of this solution is also given in Table V. These two solutions are mixed in the in the f / ·

Combined with one another as indicated in the table. During the reaction that occurs, the sodium is converted from the sodium metasilicate removed, and an "active" silica or an "active" silicate is obtained as the precipitate, but without a Temperature rise is observed. "'·

The precipitate is filtered off from the mixture, washed with water until the concentration of entrained sodium salt is less than 2 wt. $, and then at the specified temperature dried. The product purified in this way is analyzed by means of the tests described above and the activity evaluation is determined. The results are also shown in the table V.

00984971719

Experiments 1 to 4 of Table V show the effect of the precipitation of only part of the silica content of the sodium metasilicate used as the starting material. When about 90% of the silica is precipitated, only a slight increase in activity is observed (see experiments 1 and 2j, while a substantial increase in activity occurs when only a third of the silica content is precipitated / see experiment 3J. However, if practically the entire silica content If the outlet metasilicate is precipitated, an increase in activity is observed at all (see experiment 4) · (

Went) ammonium nitrate is used as a precipitant and you get the solution. B is added to solution A (cf. Experiment 5), then about 94 % of the silicic acid content of the starting material is dropped, and a certain increase in activity is retained ... "" ■ '

In the experiments 6 and 7 ammonium chloride is used as the precipitating agent and the solution B is set to the solution A züge- λ to cause precipitation outside of the preferred temperature range. Practically no change in activity is observed in this pail.

Experiment no. O relates to the use of methylammonium chloride as ■ Pällungp.mittel at a temperature of 50 ⁰ C, while it; Experiment no. 9 carbon dioxide used as a precipitating agent wi tu.

009849 / 17T9

Experiments 10, 11 and 12 illustrate the production of a "Active" silica-containing product according to the invention under continuous process conditions. With these

and
search solution A "solution B is pumped through adjacent lines of identical diameter of a Y-shaped line and mix in the third common line section. The slurry withdrawn from the third line section is filtered and the precipitated silicate product is in the above-described Wisely washed and dried. If only a portion of the total silica content of the sodium metal silicate starting material is precipitated (see request 1: 2), then a significant activity occurs! Tat sans-ti eg;

Example 2 . .

In this comparative example, a Sodium metasilicate with an activity rating of O was used. This sodium metasilicate provides the first active

The vitality evaluation test does not have any zeolite X and therefore has an activity rating of 0.

An aqueous solution of the inactive sodium metasilicate is prepared which contains 2 gramol of silicate per 1000 g of solvent. 50 ml of this solution are added with stirring to 50 ml of an aqueous solution which contains 5 gram mol of ammonium chloride per 1000 g of solvent. The resulting mixture has a temperature of 25 ⁰ C. In this way, 96% of the silica content of the starting metasilicate is precipitated and

009849/1719

This precipitate is filtered off, washed for removal of entrained sodium salt and dried at 25 ⁰ C. The product thus obtained was subjected to the activity tests described above, and the activity rating was found to be.

Example 5

This example illustrates the preparation of crystalline zeolites using those prepared according to the invention "active" siliceous compounds.

A number of experiments are carried out in which an aqueous solution of an "active" sodium metasilicate with a Solution of ammonium carbonate is treated. In this way, practically the entire silica content of the sodium metasilicate is removed failed. The composition of the mixture obtained in this way is then adjusted in such a way that it contains the reaction components for the preparation of a desired special Contains zeolite in the appropriate and required proportions.

The conditions and results used herein are as follows compiled in Table VI.

The "active" sodium metasilicate starting material corresponds to the formula Na ₂ O i SiO ₂ : 1 _→ 18 H ₂ O and has an activity rating of 200 units. A solution is prepared which contains 2 gramol of the metasilicate per 1000 g of water .

009849/1719

250 ml of this solution are added at room temperature and with stirring to 250 ml of an ammonium carbonate solution which contains 2 grams of ammonium carbonate per 1000 g of solvent. The mixture is stirred until the precipitation is practically complete. In this way 98 % of the silica content of the "active" sodium metasilicate is precipitated.

In each experiment, the composition of the mixture obtained is adjusted in such a way that a zeolite reaction mixture is obtained obtained, which has the reactants in the molar ratios as given in Table VI are. The silica component of the zeolite reaction mixture consists entirely of the silica-containing product, which obtained by precipitating the silica content of the sodium metasilicate. The aluminum oxide component of the reaction mixture consists of sodium aluminate or sodium and Potassium aluminate. If more potassium oxide is required, this is added in the form of potassium hydroxide.

The molar ratios of the alkali metal oxide component of the reaction mixture are derived from the total sodium and total potassium content the same calculated. It has already been pointed out above that carbonate ion present in the reaction mixture masks the effect of the sodium component in the reaction mixture, and so does the potassium component. In the experiments indicated is the number of effective moles of alkali metal oxides in the reaction mixture according to the equation below with the total amount

009849/1719

of alkali metal oxides in moles and the total amount of carbonate ions related in moles in the zeolite reaction mixture:

Number of effective moles - ^

of alkali metal oxides = 10 total amount of alkali metal oxides - Total amount of carl) ions in moles

2 + total amount of carbonate ions in moles

Using this relationship, the effective molar ratio NapO + KpO / SiOp has been calculated in Table VI.

The reaction mixture is heated to a temperature of 90 to 100 ^° C. with stirring and kept at this temperature with stirring for the periods of time indicated in Table VI.

The crystalline zeolite obtained in each experiment is filtered off from the Reaktionsmiscliung, up to a pH of about 10 and then incubated at 100 ⁰ * G dried.

The individual crystalline zeolites are made by Rontgenbeu- ™ powder diagrams identified.

The LS 102 zeolite produced in this way was also analyzed and accordingly had the following composition;

0.46 K ₂ OJ 0.27 Na ₂ O: Al ₃ O ₃ : 7.1 SiO ₂ : 9.7 H ₂ O.

0098A9 / 1719

O O (O

Solution a Solution b gMol
Per
1000 g
Solution
middle Art
the
Failure
lung Table V Dry
potential
tempe-
• rature
⁰ C - 32 - ■ In the precipitation
product
included
SiOg des
Starting
materials
in wt ■ Formula
of
Falsification
lung
Per-
dukts Active
physical
apply
tion
of
Falling
Products Activity
valuation
of the Na meta-
silicates
in
Solution a (Ka-meta-
silicate)
g mol /
1000 g
Solution
middle Falsification
lung
middle 5.55 50 ml A
to 50ml
B train
puts 25th 90 0.009
Na ₂ O:
Si0 _P :
0.7T H ₂ O 30th 5 Ver
search
No. 2.0 NH ₄ Cl 5.0 50 ml A
to 50ml
B train
puts Tempe
rature
at
the
Failure
lung
⁰ C 25th 87 0.011
Na20:
SiOg:
0.65 H ₂ O 130 20th 1 2.0 NH ₄ Cl 5.55 100ml A
to 50 ml
B train
puts 25th 25th 34 0.19
NagO:
SiOg:
0.98 H ₂ O 520 5 2 2.0 NH ₄ Cl 5.0 50 ml A
to 125ml
B train
puts 25th 25th 98 0.007
Na ₂ O:
SiO ₂ :
0.69 H ₂ O . 60 60
I. 3 2.0 NH ₄ Cl 15.0 25 ml B
to 50 ml
A train
puts 25th 25th 94 0.009
Na ₂ O:
S1O2:
0.075HpO 40 5, 4th 2.0 NH ₄ NO ₃ 25th 5 25th

• Table V (continued) - 33 - Ver
search
No.- Solution a Solution b gMol
jro
1000 g
Solution
middle Kind '
the
Failure
lung Tempe
rature
at
the
Failure
lung
⁰ C Dry
potential
tempe-
rature
⁰ C In the precipitation
product
included
SiO ₂ des
Starting
materials
in weight # formula
of
Falsification
lung
Per-
dukts Activity
valuation
of the Na-Meta
Silicates
in
Solution a δ? 6th (Na-meta-
silicate)
g mol /
1000 g
Solution
middle Falsification
lung
middle 4.0 100ml B
to 100ml
A train
puts 10 · 25th 85 ' 0.012
SiO ₂ :
0.8 H ₂ O 30th 7th 2.0 NH ₄ Cl 4.0 100ml B
to 100ml
A train
puts 75 80 - 0.008
Na ₂ O:
SiO ₂ :
0.45 H ₂ O 10 8th 2.0 NH ₄ Cl ioo (r> / 600ml A
to 1OmI
B train
puts 50 25th 95 0.008
Na ₂ O:
SiO ₂ :
0.85 H2O 5 in 9 2.0 Methyl-
Ammoni
around-
chloride By
pearls
by
Solution a 25th 25th 90 0.009
Na ₂ O:
SiO ₂ :
0.89 H2O 15th 10 2.0 CO ₂ 3.5 continu
respectable.
VermiscJi
from solution A.
uB b.gli 25th
5- 25th 0.012
Na ₂ O:
SiO ₂ t
0.95 H ₂ O 20th 1.5 NH ₂₁ Cl Hk tivi-
; äts-
apply
tion
.it
Pelling
Product 10 30th 5 50 60

O O CD OO

Solution a Solution b Pal gMol Tabel Art Tempe A and solution V (port setting) In the Pällungs- formula - 34 - Active 0 125 Activity - 5 (Na-meta- lung
middle Per
1 000 s rature B; Stromgs.- Dry product of physical valuation Ver silicate) XiIX UUw-X Solution UCX at Speed * potential included Falsification apply of the Na meta- search g mol / Failure the ability of Lö tempe- SiO ₂ des lung tion silicates No. 1000 g 3.0 lung Failure solution B dop rature Starting Per- of in solution A Solution NH ₄ Cl lung pelt so materials dukts Pelling middle ⁰ G as big as in weight $ product 1.5 Continuity 25th those of ⁰ C 0.01 30th 15th 11 respectable. Solution A. 80 "Na ₂ O: Mingling. SiOp: from solution A and Lö 0.35 H ₂ solution B at same cher NH. α 4.0 Stromgs.- Speed age 2.0 Continuous, 25th 14.5 0.1 12th respectable. 25th Na ₉ O: Mingling. v. solution Λ Λ TT / * \ 1,1H ₂ O

Ver Table 71 Total-
Na ₂ 0 + Kg0 / Si0 ₂ HjO / overall
KägO + KgO ^ι KnO / total
Na _g 0 + KgO Effective
Na ₂ O + K ₂ O • Reaction
Time, P.
r - 35 - V) search
ffr. 1.78 40 O SiO ₂
in zeolite
Reaction
mixture H 126393 20th Manufacture of zeolites: . 1.56 42 O 1.32 3 end 21st 2.06 34 O 0.26 96 proUUK u O
O
co
ep 22nd • 2.06 34 0.45 0.48 4th Zeolite X (O 23 Composition of the zeolite reaction mixture in
Mo! Ratios of the oxides _Λ 1.58 40 0.33 0.48 16- Zeolite S - -J
co 24 SiO ₂ ZAl ₂ O ₅ 0.22 192 Zeolite Y 3.85 Zeolite K ¹ M 20 ' Zeolite 20th LS 102 20th - 25th

2Q26393 - 36 -

Table VII

X-ray powder diffraction pattern of Zeolite LS 102

d is the lattice planes - distance in Angstrom units and the

relative intensity 1001 / lo is derived from the intensity; I this vertex and Io is the height of the vertex strongest line. The relative intensity is given by the following Abbreviations: expressed; :,.

= very strong

S '= strong

. w = medium

w / = weak

vw / = very weak

a Relative intensity

12.0 vs.

7 * 8 m

6f8 B

6j5 w

5.6 VW 5.4 vw

4.7 w 4.4. m 4.15 w

3.82. _w 3.79 ve 3.60 β 3.32 w 3.15 m 2.92 vw 2.85 ve 2.67 w 2.48 m 2.2Q vw 2.12 vw 1.90 m

1.83 w 1.76 m 1.68 vw 1.64 m 1.55 w

Q098A9 / 1719

Claims (10)

Claims η Na ₂ O: SiO ₂ : x H ₂ O, in which η has a value from 0 to less than 0.5 and χ has a value of more than 0.05, preferably of at least 0.1, by partial or complete removal of the cation from an "active" sodium silicate hydrate of the general formula m Na ₂ O: SiO ₂ : y H ₂ O, in which m has a value of 0.5 | to 1.5 and y has a value above 0.05, characterized in that the "active" sodium silicate hydrate with the salt of a nonmetallic base, which has a pK, value of 2.0 to 9.0 or with a weak acid, which has a pK value of 5.0 to 9.0, is reacted. 2. The method according to claim 1, characterized in that for the implementation of an ammonium salt of carbonic acid or _a comparable is turned. 3. The method according to claim 1 and 2, characterized in that the reaction is carried out in an aqueous medium. 4-. A method according to claim 1 to 3, characterized in that the reaction is carried out at a temperature of 10 to 30 ⁰ C. 00984 9/1719 5. The method according to claim 3 and 4, characterized in that that the precipitated silica-containing product is separated from the aqueous medium in order to free it from entrained Sodium salts, free base or other impurities are carefully washed and then dried. 6. The method according to claim 3 to 5, characterized in that that an "active" sodium silicate with an activity rating of at least 1 is used as the starting material and that only part of the silica content of the starting material is due to the treatment with the salt or a weak acid is precipitated. -. ■ 7. Use of the prepared according to claims 1 to 6 "active" silicate products or "active" silicates for the preparation of crystalline synthetic zeolite molecular sieve and Basenaus- - taiuscheigenschaften in an aqueous aluminosilicate Reaktionslösüng at temperatures between 30 and 120 ⁰ C. 8. Embodiment according to claim 7, characterized in that a compound of the formula η Na ₂ O: SiO ₂ : x H ₂ O is used as the "active" silicic acid-containing component, in which η has a value from 0 to less than 0.5 and χ has a value of at least 0.1. 009849/1719 9. Axis filling form according to claim 7 and 8, characterized in that that additionally cations other than sodium and possibly non-active silicic acid-containing compounds can also be used. 10. Aitsflihrungsform according to claim 7 to 9> characterized in that the "active" silica or the "Afetiven" silicates for the production of a zeolite general formula. ^ 0.7 Ms 1 _f 3 Cd (Na ₂ O! (Id) K ₂ O): Al ₂ O ₅ : e SiQ ₂ : f H ₂ O can be used, where d has a value from 0 to 1, e has a value of 6 to 8 and f has a value up to about 10 and the zeolite is characterized by the X-ray powder diffraction diagram given in Table VII and that the aluminosilicate reaction mixture has the following molar composition: 15 to 30 0.2 to 0.6 20 Ms 100 lTa ₂ 0 / ^ Ia ₂ 0 + K ₂ 0 O ₁ 1 Ms 0.9 0098 / .9 / 1 7 1 9