DE1542321B - Process for the production of Zeohth-like catalysts - Google Patents

Description

1 2

The invention relates to a method for producing pressure at least 12 hours at one temperature

of zeolite-like catalysts by reaction from about 21 to 54 ° C, because this results in the following

a deformed mixture of dehydrated crystallization in the form of a zeolite is favored.

Kaolin and alkali lye and subsequent crystalline The treatment of the product is preferably carried out

sation of the zeolite. 5 mix at 21 to 54 ° C under such conditions

A process of this type for making syn- by ensuring that the particles are not in direct contact

thetic zeolite is from the USA patent with an outer aqueous phase to prevent the un-

2,992,068 known that the synthesis of molecularly desirable leaching of sodium hydroxide from the

seven immediately in the form of particles to avoid the need for the reaction mixture.

Describes use of desired size and shape. io The one following the ion exchange

Preformed thermal activation is preferably used at 535 to

Metakaolin particles and concentrated caustic soda. 93O ⁰ C carried out to obtain particles that

The conversion results in extremely pure zeo, when used as cleavage catalysts, a special one

have lithic molecular sieves with pore diameters of high activity and selectivity,

about 4 Ä. For the use of such molecular 15 From the USA. Patent 2,962,435 a catalog is

sieves as a starting material for cracking catalysts for the cracking of nitrogen compounds

however, these pores are too small. Furthermore, the contaminated hydrocarbons are known from

the known method obtained zeolite-like a mixture of a synthetic crystalline

Particles for use as catalysts are not molecular sieve which acts as an adsorbent, and

hard enough. 20 acid activated clay or amorphous silica

The invention is based on the object of a compound alumina gel which uses the latter as a catalyst

drive to the production of synthetic zeolites acts. The mixture can be created by simply mixing

to make available in the case of the particles with a considerable amount of particles of the two components or through

borrowed larger pore diameters by, for example, letting the gel crystallize in the presence of

13 Å of the structure of the faujasite result, the 25 set molecular sieve crystals are produced,

also are significantly harder than those according to the method according to the invention does not require

Zeolite part obtained above - the use of the highly pure diluted

chen and which are therefore suitable for use as catalysis reactants from which the as starting material

gates, especially as cracking catalysts, are suitable, the crystalline zeolite used according to the USA.

high activity, mechanical strength, heat must be produced. Further

resistance and good regenerability arise in the process of the invention directly

point. bar usable for the catalytic cleavage partial

It has been found that the formation of signs without there being a subsequent process lith-like Particles with much larger pores need to bind the mixture components, knives than they are in the method according to FIG. 35 as required by the United States patent. USA.-Patent 2,992,068, thereby causing- Finally, it is produced in the reaction mixture itself can be that in addition to meta-induced crystallization according to the invention for kaolin a calei- formation of extraordinarily hard and abrasion-resistant conditions under more severe conditions Clay is used, and that you get particles of solid particles, as they are by subsequent juxtaposition Required for use as catalysts to bind molecular sieve crystals and clay Hardness is obtained when the starting material or gel particles cannot be obtained, calcined kaolin added. U.S. Patent 3,219,592 describes one

The task set is therefore in the initially method for increasing the catalytic activity

defined method according to the invention by using conventional amorphous silica-alumina

solves that a mixture of calcined and un- 45 catalysts or catalysts based on acid-

calcined kaolin and aqueous sodium hydroxide solution, activated clays. The particles become one

to 100 parts by weight of calcined metakaolin about ion exchange with copper or gold ions

50 to 1000 parts by weight of amorphous, dehydrated thrown. These catalyst particles do not contain any

Kaolin, which under such conditions differ from tempe- synthetic crystalline zeolite and

rature and time has been calcined that the 50 is therefore fundamentally different from the invention

exothermic heat emission of the kaolin after the catalysts produced.

Dehydration has occurred, about 10 to 30ge- The most more tsprozentige from the USA. Patent 3,210,267 hydroxide solution in amounts corresponding to th gap catalysts comprise a crystalline zeoetwa 0.40 to 0.75 moles of Na ₂ O per mole of Al ₂ O ₃ in the lithic molecular sieve of suitable pore calcined kaolins, and such amounts of uncalcined 55 knives (ζ. B. synthetic faujasite) and a porous cinemated kaolin that the particulate embedding mass, such as amorphous silica-alumina nature of the mixture after molding Partial gel or clay. The molecular sieve is initially retained, deformed into particles, these are produced in the form of crystals, e.g. B. by dieinem the dehydration preventing pressure of calcined or uncalcined clay for at least 12 hours to temperatures in the range 60 with dilute sodium hydroxide and a silica from 66 to 121 ⁰ C until crystallization to a former, until the zeolite crystallizes out of the solution. Zeolite has taken place, the zeolite in itself. The zeolite obtained in this way or a commercially known way of ion exchange with hydrogen, zeolite powder is then mixed in with the embedding compound ammonium or non-alkali metal cations and the mixture is shaped into particles. When throws and the 65 subjected to the ion exchange this known process takes place thermally activated in the counter-zeolite. sentence to the invention no direct crystallization

According to a preferred embodiment of the replacement of a molecular sieve catalyst from the reactor

the particles are kept under the mixture before they are heated, and additional process

stages required in order to obtain catalyst particles that consist of the mixture specified there. The known catalyst particles also do not have nearly the same hardness and abrasion resistance

ability of the catalyst prepared according to the invention- 5 following:

particles because they are produced by subsequently binding two components together.

The constituents of the reaction mixture for carrying out the process according to the invention are

1. Anhydrous dehydrated kaolin, which has been obtained by calcining under such temperature and time conditions that the characteristic, exothermic kaolin heat tone, which ^{takes place at about 98O 0} C, did not take place after the dehydration (ie metakaolin) 100 parts by weight

2. Anhydrous dehydrated kaolin obtained by calcining under such temperature and time conditions is that the exothermic kaolin heat tone after the

Dehydration has taken place from 50 to 1000, preferably from 300 to

700 parts by weight

3. NaOH corresponding to 0.40 to 0.75 mol Na ₂ O

per mole of Al ₂ O ₃ in 1 and 2

4. Water in the to form 10 to 30, before

preferably 12 to 18 weight percent sodium hydroxide solution with the
NaOH required amount

5. Uncalcined, fully hydrated kaolin around a coherent mixture of 1, 2, 3

and 4 to form

The hydrothermally reacted particles contain a complex, crystalline sodium aluminosilicate hydrate of significant base exchange capacity and hydrated clay. In particular, the hydrothermally converted material contains a microcrystalline, zeolitic molecular sieve with the X-ray diffraction diagram of a sodium zeolite X or the sodium zeolite Y, preferably a form of sodium zeolite Y with a high molar ratio of silicon dioxide to aluminum oxide of at least 4, which is strongly bound with microcrystalline kaolin.

In order to convert the particulate molecular sieve into an active cleavage catalyst, a considerable part of the sodium ions is exchanged for non-alkaline cations, such as ammonium ions, hydrogen ions J and / or cations of metals from group IB to VIII of the periodic table. Then the particles are dehydrated and activated by heat treatment. The hardening heat treatment can be carried out before it is introduced into the catalytic cracking system, but also in the catalytic cracking system itself.

The cleavage catalysts are preferably by ion exchange with ammonium ions and then Heat activation established.

The catalysts prepared according to the invention are suitable for the cleavage of hydrocarbons at catalyst temperatures of about 425 to about 540 ° C., pressures of 1 to 4 ata and high degrees of conversion of more than 55%. They are highly selective even at very high degrees of conversion and therefore give high gasoline and low coke and gas yields. Coke formation is usually considerably less than when using commercial kaolin catalysts at the same degree of conversion. The catalysts prepared according to the invention are superior to the acid activated clay catalysts. Catalysts made with the preferred amounts of ingredients are superior to other molecular sieve catalysts in regenerability because they maintain a high level of selectivity with good conversion levels even when steamed under conditions of temperature and time similar to others Catalysts lose their activity and selectivity. The mechanical strength of the new catalytic converters is largely retained after steam treatment. The catalysts therefore do not suffer any damage if they are inadvertently exposed during use or regeneration to thermal conditions under which other catalysts become unusable. The catalysts produced according to the invention can be extruded into pills which meet the technical hardness requirements for grade A.

If the ratio of high temperature calcined clay to low temperature calcined clay is significantly greater than the preferred ratio given above, difficulties in crystallizing the product may arise and the product may not have the desired cleavage properties. On the other hand, if the ratio of high temperature calcined clay to metakaolin is considerably less than the preferred ratio of the present invention, the resulting catalyst does not have the exceptional heat resistance of the catalysts made with the preferred ratio of about 6 parts high temperature calcined clay to 1 part metakaolin. The latter may therefore still be useful after having been steamed for several hours at temperatures well above 870 ° C. In contrast, catalysts which have been, however, made from similar reactants with 2 to 3 parts hochtemperaturcalciniertem clay to 1 part tieftemperaturcalciniertem clay, be limited in their utility to operations in which subject the catalyst to a steam treatment at less than 843 ⁰ C. will.

"Kaolin" refers to clays whose main mineral components are kaolinite, dickite, Can be anauxite, nacrite or halloysite. These minerals are hydrous crystalline aluminum silicates the general formula

Al ₂ O -2SiO ₂ - ^ H ₂ O,

where X is usually 2, with the exception of (various halloysites where X = A.

Reactants 1. The low-temperature calcined kaolin This clay, which usually contains as "metakaolin" beKaolin as a diluent, can be easily deformed if one uses a kaolin of good plasticity. 'But you can also add additives that make extrusion easier. The particles can also be made by compression molding or spray drying. In the latter case, the catalyst is obtained in the form of microspheres with particle sizes between 44 and 150 μ. In this case, the initial mixture of ίο alkali and clays with an alkali of less than 10%, e.g. with 5% strength sodium hydroxide solution, ^it can be prepared. This slurry then turns into microspheres of for the following by spray drying ^{at temperatures not exceeding 55 ° C.}

is drawn, an amorphous, practically anhydrous 15 heat treatment suitable Na ₂ O / H ₂ O content is deformed and then made to crystallize. Compression molding can require slightly more uncalcined clay than other molding methods. The solids can also be placed on a rotating pan (e.g. i)

Aluminum silicate of the approximate formula Al ₂ O -2SiO

and is obtained by adding kaolin at 540 bis

845 ⁰ C calcined until the loss on ignition below 1% ^{20 of} a Dravo mill) are agglomerated.

located. Under these conditions the clay does not have the characteristic kaolin heat output after the Suffered from dehydration. One can use metakaolin, which contains the usual impurities of the Starting kaolin contains such as titanium oxide, mica, quartz, feldspar and ferrous substances. The calcining of kaolin in the Nichols-Herreshoff furnace is described in U.S. Patent 3,014,836. Around According to this patent specification, to obtain metakaolin, the kaolin is only passed through heating zone no. 3 of the furnace out so that all of the chemically bound "water is removed.

2. The high-temperature calcined clay For use in the fluidized bed, the Catalyst grain sizes from 74 to 150 μ have; particles of about 4.7 to 2.4 mm.

implementation

The reaction mixture is converted to a synthetic, crystalline zeolite under conditions preventing dehydration at suitable temperatures. The reaction mixture is first aged for at least 12 hours, preferably 24 hours, at temperatures of about 21 to 55 ^° C. and then for 12 to 44 hours, or until the zeolite crystallizes, without dehydration to temperatures

The clay is an amorphous hochtemperaturcalcinierte 35 heated from about 65 to 12O ⁰ C. The thus obtained zeolite material obtained by calcining kaolin at 870
f up to 1095 ⁰ C up to a loss on ignition below 1% and
is obtained for such a period that the
Kaolin exotherm has occurred after the dehydration has essentially ceased. Even for 40 to 48 hours at a low temperature, kaolin can be lent to this raw material and prevent crystallization. The favorable

has the X-ray diffraction spectrum of “sodium zeolite y” (cf. USA. patent 3 130 007) or of “sodium zeolite X” (cf. USA. patent 2 882 244). Prolonged aging, e.g. B. much longer

which contains the usual impurities. The kaolin heat dissipation can easily through Differential thermal analysis according to the method determined maximum aging time depends on the aging temperature and the dosage of the caustic alkali. As mentioned, the reaction under such conditions

carried out by Ralph E. Grim in “Clay Mine- 45 Conditions That No Dehydration

ralogy ", p. 203 (McGraw Hill Book Company, Inc., 1953). This form of calcined Clay can be obtained by passing the clay through the seven heating zones of the Nichols-Herreshoff oven according to U.S. Patent 3,014,836.

Preparation of the Reaction Mixtures The solids in the reaction mixture should be particulate particulate reaction mixture takes place. The reaction components in the reaction vessel The vapor pressure exerted must be equal to the vapor pressure of the reactants Heating temperature is generated at which both the dehydration and the condensation, the undesirable leaching is prevented. The simplest methods for Autogenous pressure is used to carry out the reaction. One method is to respond to be carried out in a closed vessel. Another way to get the particles under handy to maintain autogenous pressure consists in keeping the particles in a non-reactive hydrocarbon

are less than 74μ in size. The mixture can be prepared in the screw mill, or the alkali can be added to a mixture of the calcined kaolins at room temperature and then this mixture by adding uncalci-

ned clay to a polluting oil suitable for deformation, which is at the desired temperature

bring stability. temperature is maintained.

The reaction mixture can be converted in bulk and then granulated; preferably however, the reaction mixture only becomes particles of the shape desired for the finished catalyst and size deformed, as this shape is retained during further processing. If the reaction mixture contains significant amounts of uncalcined Ion exchange and activation

The reaction product is preferably subjected to ion exchange prior to thermal activation subjected and then dehydrated by calcining.

For ion exchange, salts of ammonium,

Barium, calcium, magnesium, manganese, chromium, cobalt, nickel, iron, zinc, aluminum, rare earth metals (Lanthanum, praseodymium, neodymium, cerium and samarium) or precious metals, such as platinum and palladium, Acids or mixtures of metal salts and ammonium salts can be used. The specific Effects of these and other cations of groups IB to VIII of the Periodic Table on fission catalysts of the molecular sieve type are known. Inorganic salts, such as chlorides, or organic salts such as acetates. Usually the ionizable Salts used in the form of aqueous solutions.

For activation, the products of ion exchange may be treated at about 540 to 87O ⁰ C with 100% steam for 2 to 4 hours. This dehydrates and hardens the particles. Optionally, the particles may be prior to the steaming ¹ J ₂ to 24 hours in air at 425 to 650 ° C calcined, or they can be calcined in air at temperatures up to about 930 ⁰ C instead of the steam treatment.

example 1

The procedures described in this example use the following kaolin clays:

) Satinton No. 1 « "Satinton No. 2" "Mm-Chem Special" not 2.63 2.50 2.58 calcined 1.0 1 = 0. 1.0 0.5 0.5 0.5 2.0 4.5 3.5 crystalline 5.8 to 6.3 5.8 to 6.3 3.8 to 5.0 (Kaolinite) 0.5 0.9 13.8 52.3 52.1 45.4 44.6 '44.4 ■ ;. 38.8 track track 0.3 2.0 2.0 1.5 above exo below exo Thermer Thermer reaction reaction calcined calcined amorphous amorphous (Meta- kaolin) ■

Physical characteristics

specific weight

Moisture, maximum, weight percent ...

Weight percent> 74 μ (wet sieve analysis) ...

Mean particle size, μ

pH

Typical chemical analysis (on a weight basis,
moisture-free)

Loss on ignition at 982 ° C,%

Silica,%

Alumina,%

Iron oxide

Titanium dioxide,%

Calcination treatment

composition

According to the invention, a pelletized zeolitic cracking catalyst becomes remarkable in activity and regenerability, which meets the hardness requirements for grade A pelletized catalysts is sufficient, made from a mixture of clays, as follows:

3887 g of Satinton No. 1 and 648 g of Satinton No. 2 are slowly mixed in a pan with 4000 ml of 16% strength by weight sodium hydroxide solution using a glass rod until a uniform consistency is achieved. The mixture of satin clay and sodium hydroxide solution is added to 9085 g of “Min-Chem Spezial” in a twin-screw kneader. The pan is rinsed with 500 ml of 10% sodium hydroxide solution, which are also added to the kneader. In order to make the mixture extrudable in the kneader, a further 350 ml of 16% sodium hydroxide solution are added so that the total amount of 16% strength sodium hydroxide solution ^r is 5674 g. After the last addition of sodium hydroxide solution, the batch is kneaded for a further 10 minutes. At the end of kneading, the temperature of the feed 31 ⁰ C. The mixture is extruded under a vacuum from 711 to 732 mm Hg by means of a Schnekkenstrangpresse with holes of 4.32 mm in diameter and the strands are of 6.35 mm length to form pellets cut up. Within the first half hour, the temperature exiting the extruder material gradually increases from 33 ⁰ C to 51 to 52 ° C at. The extrusion time is 34 minutes with the applied force 11.97 kWh / t.
1.9 1 glass barrel ports are completely filled with the fresh extrudates, sealed, stored for 24 hours at 24 ° C and then 24 hours in a 93 ⁰ C oven used. The X-ray diffraction diagram shows the presence of kaolinite and crystalline sodium zeolite Y with a molar ratio of SiO ₂ to Al ₂ O ₃ of more than 4.

Without washing or drying, batches of the pellets of 800 to 900 g each are subjected to ion exchange with ammonium nitrate solution for ^{48 hours at 82 ± 6 ° C. in a column.} At the end of the exchange process, the Na ₂ O content of the flowing solution, determined electrometrically, is 0.027% and the pH value is 7.3. The Na ₂ O content of the particles after the ion exchange is in the range from 0.44 to 0.78% (based on the weight of the particles without volatile components).

Four samples of these particles (pellets) are stabilized in the tube furnace for 4 hours each with 100% steam. ^{Steam at 843 °} C. is used to treat the first sample. The product is referred to as "Catalyst A". The second sample is treated with steam at 857 ° C and results in "Catalyst B". The third, at 871 ° C with steam

109 536/348

treated sample provides the "catalyst C". In order to determine the upper limit of the thermal stability, the steam treatment is carried out on a fourth sample at 896 ° C ("Catalyst D"). After the steam treatment, the physical characteristics of the catalysts are determined and the catalytic properties are investigated using the "CAT-D" method described below. The four samples of the clay catalysts, which each contain less than 1% Na ₂ O and analytically consist of about 45% Al ₂ O ₃ and the remainder of SiO ₂ , are practically the same with a commercially available pelletized, acid-activated cracked catalyst of hardness type A chemical composition ("catalyst E") compared to that obtained by pelletizing uncalcined kaolin with concentrated sulfuric acid, reacting with the sulfuric acid and immediately thermally desulfating the pellets under reducing conditions without washing out the soluble components, and before testing for 4 hours in air at 566 ° C has been calcined. The results are summarized in tabular form.

In the ball mill hardness test, samples of particles with grain sizes of more than 3.96 mm are calcined in a muffle furnace at 566 ° C, stored in the desiccator and, with gentle tapping, in tared, graduated 100 cm ³ cylinders up to 80 cm ³ - The mark is poured and the 80 cm ³ weight of the sample is determined. The 80 cm ³ sample is then placed in a cylindrical stainless steel container with four polished stainless steel ball bearing balls 23.8 mm in diameter. The container is tightly closed and allowed to rotate around its longitudinal axis on rollers at 80 rpm for 1 hour. The particles are then screened out on a 3.327 mm mesh screen and the hardness is calculated from the percentage of the weight of the total sample retained on the screen.

ίο The method for determining the air jet hardness is described in U.S. Patent 3,024,206.

The "CATO-D" test is a modification of the "CAT-A" method described in "Laboratory Method for Determining the Activity of Cracking Catalysts" by J. Alexander and HE S him ρ, S. R 537, National Petroleum News, August 2, 1944. When CAT-D test a feeding is used from heavy gas oil and carried out the cleavage at 482 ⁰ C with 10% water vapor and a liquid throughput rate of 1.0 for a 15minutige operating time.

The term "kaolin coke factor" used when rendering comparative catalytic data is used refers to a value obtained by comparing the coke deposit on the test catalyst with that on a commercially available kaolin catalyst, with the same degree of conversion (extrapolated) is obtained.

catalyst

Steam treatment

⁰ C

Hours .......

Physical Properties
Bulk density

hardness

BMH *

AJH **

Splitting power

Gasoline, volume percentage

Coke, weight percent

Gas, weight percent

Gas density

Degree of conversion, percent by weight
Coke factor

843 4

0.927

97.7 19.3

52.5

2.3 14.8

1.48 60.5

0.46

857
4th

0.936

96.1
21.3

50.5

1.7
12.4

1.46
55.8

0.43

871
4th

0.942

96.7
25.3

46.6

2.0
12.1

1.39
52.7

0.56

896
4th

0.964

95.8
15.6

38.6
1.4
8.2-1.28

41.3
0.69

none
none

0.779

99.1
26.3

35.0

4.2
20.4

1.45
55.4

1.08

Ball mill hardness. ** Air jet hardness. ♦ * ♦ Comparative catalyst.

The values in the table show that the experimental catalyst which is highly selective for the formation of gasoline, thermally and mechanically stable even after a steam treatment at 871 ⁰ C.

The catalytic values in the table also show that the experimental Kaolinkatalysatoren which have been steam-treated at 843-871 ⁰ C, as a cracking catalyst are considerably more effective than the non-steamed, commercially available, acid-activated Kaolinkatalysator and similar or slightly higher conversion levels considerably more Deliver gasoline. Also show the catalytic values that the attempt catalyst, although it suffers a certain loss of activity during heat treatment at 896 ° C, is comparable after steam treatment at 896 ⁰ C with respect to the yield of gasoline with the non-treated with steam commercial clay catalyst.

Example 2

This example shows some of the effects of changing the sodium oxide content in catalysts made in accordance with the invention, as well as the higher selectivity of the high sodium oxide catalysts. The example also shows the superiority of the catalysts prepared according to the invention over known, commercially available zeolitic molecular sieves with an embedding mass of silica-alumina gel.
When operated in a test facility under

Using the ingredients and amounts given in Example 1, a pelletized catalyst base material is made to crystallize, which consists of 6.02% Na ₂ O and the remainder of SiO ₂ and Al ₂ O ₃ ¹ in a weight ratio of 1.17: 1 exists. The pellets are batchwise ion-exchanged with an ammonium nitrate solution, and samples are taken in various stages of the ion-exchange process. In this way pellets are obtained which contain 0.82, 1.28, 1.79, 2.26, 2.78 and 3.96% Na ₂ O, respectively (on a weight basis of the pellets without volatiles). The X-ray diffraction diagrams of the pellets before the exchange treatment show that they contain 20% sodium zeolite Y with a molar ratio of SiO ₂ to Al ₂ O ₃ of 4.28: 1. In order to control the degree of conversion and to investigate the effect of the steam treatment conditions on the activity and selectivity, samples of the pellets are ^{calcined after the ion exchange for 4 hours at 788, 871 or 899 °} C. in steam of 1 atm and evaluated for their catalytic properties. Some samples are steamed for a further 4 hours and reassessed. A commercially available, highly active, zeolitic molecular sieve catalyst is treated comparatively in the same way.

It is found that the pelletized catalyst containing 3.96% Na ₂ O, which, after steaming at 732 ⁰ C excellent activity and selectivity. After 4 hours of steam treatment at 788 ° C, however, it is practically inactive and only gives a degree of conversion of the starting material of 25%. The 2.78% Na ₂ O-containing catalyst is after 4 hours steam treatment at 788 ⁰ C still active and highly selective (degree of conversion 66%), but it loses after repeated steam treatment at 788 ° C its activity.

A comparison of the activity of the catalysts prepared according to the invention containing 0.82 to 2.26% ^Na 2O with the comparative zeolite catalyst shows that the former retain high levels of activity with degrees of conversion above 60 percent by weight when treated with steam under conditions below which the comparative catalyst loses its activity.

The cracking efficiencies of the catalysts are determined by dividing the percentage by weight of gasoline yield by the percentage by weight of conversion and multiplying the result by 100. After the steam treatment at 788 and 843 ^° C., the comparative catalyst has a calculated cracking efficiency of 71.2 and 70.6%, respectively. These values represent gasoline volumes of 32.6 and 51.7% at steam treatment temperatures of 816 and 788 ^° C., respectively. Catalysts produced _{according to the invention which contain 0.82 to 2.78% Na 2} O have after activation at 843 to 899 ° C much higher calculated cracking efficiencies than the comparative catalyst. For example, the catalysts with more than 1.78% Na ₂ O have exceptionally high cracking efficiencies of 75 to 78% after activation at up to 816 ° C. The catalysts with 0.82 to 1.28% Na ₂ O have cracking efficiencies of 60 to 69% after steam treatment at 816 ° C. The latter catalysts, however, operate at extremely high conversion levels (over 70%) - accordingly ίο total gasoline production is excellent, although the ratio of gasoline formation to total conversion level is less than at much lower conversion levels.

Claims (4)

Patent claims: 1. Process for the production of zeolite-like catalysts by converting a deformed one Mixture of dehydrated kaolin and alkali and subsequent crystallization of the zeolite, characterized in that a mixture of calcined and uncalcined kaolin and aqueous sodium hydroxide solution, the for 100 parts by weight of calcined metakaolin about 50 to 1000 parts by weight of amorphous, dehydrated Kaolin that has been calcined under such conditions of temperature and time is that the exothermic warming of the kaolin took place after dehydration, for example 10 to 30 weight percent sodium hydroxide solution in men-. gen, corresponding to about 0.40 to 0.75 moles of Na ₂ O per mole of Al ₂ O ₃ in the calcined kaolins, and contains such amounts of uncalcined kaolin that the particulate nature of the mixture is retained after shaping into particles, into particles deformed, these heated under a pressure preventing dehydration for at least 12 hours to temperatures in the range from 66 to 121 ⁰ C until crystallization to a zeolite has taken place, subjects the zeolite to ion exchange with hydrogen, ammonium or non-alkali metal cations in a manner known per se and thermally activated the ion-exchanged zeolite. 2. The method according to claim 1, characterized in that the particles are prior to heating under pressure for at least 12 hours at a temperature of about 21 to 54 ° C. 3. The method according to claim 1 and 2, characterized in that the treatment of the mixture Performs at 21 to 54 ° C under such conditions that the particles are not in direct contact stand with an external aqueous phase. 4. The method of claim 1 to 3, characterized in that the subsequent to the ion exchange thermal activation is carried out at about 535 to 93O ⁰ C.