DE1816822A1 - Method of making a catalyst - Google Patents

Description

Method of making a catalyst 1 priority: December 29th 1967 Great Britain January 25, 1968 The Netherlands Registration numbers: 59 244/67 68 Ol 107 The invention relates to a method for producing a catalyst the base of a metal hydrosilicate of the zeolite type O In particular, the invention relates a process for the preparation of catalysts for hydrocarbon conversion based on zeolites of the mordenite or faujasite type.

Zeolite-type metal hydrosilicates are well known per se, you have also been used for the most varied of purposes, e.g. in particular An important application for such metal hydrosilicates is as a catalyst for hydrocarbon conversions. Although zeolite is a catalytic one in itself activity have, they will generally have one or more hydrogenating agents Metals combined which give the finished catalyst the desired hydrogenation-dehydrogenation properties to lend. Zeolites are particularly suitable as catalysts or catalyst supports of the paujasite type, in particular zeolite Y, and of the mordenite type, in general Zeolites also contain alkali metals and / or alkaline earth metals, which are either naturally present in the zeolite material or during manufacture of the synthetic Products are stored in the presence of such metals, in particular of alkali metals such as sodium, however, is useful for catalysts used for hydrocarbon conversions are determined, extremely undesirable, since such metals reduce the yield reduce the conversion products The presence of alkali metals causes also an undesirable sintering of the catalyst support material if it is the high Exposed to reaction temperatures. For this reason, the zeolite material, especially for the production of ketalysers, with a suitable cation-exchanging agent Solution treated so as to reduce the content of undesirable alkali or alkaline earth metal to belittle. Generally, one is used for this ion exchange treatment aqueous solution of an acid or an ammonium compound which then makes the zeolite is formed in the so-called hydrogen form or ammonium form.

After the ion exchange treatment, the zeolitic material becomes from Adhering exchange solution freed by a washing treatment and since dried and calcined preferably in an oxidizing atmosphere, such as Air. If the catalyst is combined with a hydrogenating metal The zeolite is supposed to be in the hydrogen form or ammonium form in general a solution brought into contact which a suitable compound of the desired Contains metal, and only then is calcination carried out.

So far, there are already satisfactory catalysts those for / hydrocarbon conversion prepared in the manner described above However, some balls have been shown to have a calcination treatment of the ammonium-treated zeolite with regard to the catalyst activity of the finished Catalyst is harmful. This catalyst deactivation is due to sintering of the metal and / or of a disruption of the active sites of the zeolite-based carrier material Her, according to the invention it is possible to overcome these deficiencies, which are particularly evident in the case of catalysts occur which have been treated with ammonium compounds.

The inventive method for producing a catalyst using a metal hydrosilicate of the zeolite type, the carrier material Treats with ammonia and / or ammonium ions during catalyst production, is loaded with one or more metals with a hydrogenating effect and calcined, is characterized in that the calcination in the presence of oxygen or one containing free oxygen Gas in controlled Way is durohführung so that the catalyst under control of the gas flow to a first calcination temperature and in a further treatment stage the final calcination temperature is heated 0.

When producing the catalyst, the zeolite material can be used in various Process stages are brought into contact with ammonium ions or ammonia. For example ammonium ions can be used in the manner described above to increase the content of alkali metal or alkaline earth metal in the zeolite material. Besides that ammonia and / or ammonium ions can also be added before or during the The metal loaded with the material can be used, however found that in some cases the presence of ammonium ions during the calcination step leads to catalysts with reduced activity without special precautionary measures.

Any catalyst deactivation can be avoided by means of the controlled calcination carried out according to the invention. The oxidative calcination according to the invention is based on the knowledge that ammonia is released from the zeolite material during the calcination treatment, which is immediately oxidized to nitrogen and water according to the following equation: The high rate of oxidation is based on the catalytic activity of the hydrogenating metal present in the catalyst. This conversion is strongly exothermic and the heat released is 75 kcal / mol NH3. The energy released can locally lead to overheating of the material to be calcined, causing the above-described damage to the catalyst. Up to now, however, it has generally been assumed that the calcination of a zeolite material loaded with metal and containing ammonium ions does not differ significantly from the calcination treatment of a zeolite material not loaded with ammonium ions.

With regard to the exothermic reaction discussed above, it is however, it is of great importance that the calcination temperature be strictly controlled will. For this reason, the zeolite material is initially heated to a first calcination temperature heated, preferably very gradually. At this first calcination temperature it is the temperature at which the decomposition of the zeolite occurs in the ammonium form, releasing gaseous ammonia, which then - as explained above - under the influence of the in the catalyst material existing hydrogenating metal is oxidized. The zeolite material will kept at the first calcination temperature until practically the entire Zeolite has been decomposed in the ammonium form.

The temperature then gradually increases to the second or final calcination temperature increased, preferably again gradually.

It has already been pointed out above that the inventive controlled oxidative calcination is of particular importance for such catalysts their production ammonia or ammonium ions for the treatment of Zeolitmatez as have been used andX or of catalysts in this case treated in this way Zeolite material is combined with hydrogenating metals, The catalysts can contain any metal hydrosilicate, for example alaminosilicates boron oxide substituted aluminosilicates, titanosilicates and ziroonosilicates. However, the process according to the invention is particularly suitable for production of catalysts based on aluminosilicates and in particular based on of aluminosilioates with a molar silica / aluminum oxide ratio of at least 3 t 1. Such aluminosilicates, which are a well-known class of Zeolites have already been widely described in the technical literature, also in patent specifications, and they can be identified by the following general molar formula with respect to their Zu.

setting are reproduced Me 2 / nO. Al2O3. x SiO2. y H2O In this Formula Ne means a metal ion with a valence, especially potassium, sodium or calcium ions, x is a number in the range from 3.0 to 15.0 and y is number im Range from 0 to 15. Particularly important representatives of this class of aluminosilicates are zeolite Y with a sea ratio of SiO2: Al2O3 between 3: 1 and 6.5 : 1 and: mordenite with a molar ratio SiO2: A1203 of about 10 : 1. All crystalline zeolites can be determined by their individual X-ray diffraction data aluminosilicates with a molar ratio SiO2 X Al2O3 of at least 3: 1 are more preferred than those with for catalyst preparation a corresponding ratio of water than 3: 1 because the aluminosilicates with a higher molar ratio of silica to aluminum oxide easily in the hydrogen form and / or a decationized form can be converted, The fact that the crystal structure is brought together.

The alumino-boro-silioate as well as the ziroono- and titanosilicates belong to a relatively new class of synthetic Zeelite, which is described in the following Past references are explained: USP 3,328,119, USP 3,329,480 and USP 9,329,4810 Naturally occurring zeolites can also occasionally be used as catalyst supports for example the following: faujasite, offretite, chabazite, gmelinite, analcite, Erionite.

The one already mentioned above is also suitable for this purpose Mordenite, which is also commercially available as a synthetic material, is included the hydrogenating metals present on or in the zeolite material these are metals commonly used for this purpose with hydrodehydrating Properties act Preference is given to metals from group VIII of the periodic table of the elements, especially precious metals of the platinum group. The implementation of the invention oxidative Calcination is surely especially beneficial when one Precious metal-containing catalysts want to calcine, because in particular metals, such as Palladium and platinum, which catalyze the oxidation of ammonia, and which in this case The heat released by the reaction causes the metals in question to sinter, whereby the activity of the finished catalyst is correspondingly reduced is0 The controlled oxidative calcination according to the invention is special Significance for the production of shaped isomerization catalysts Mordenite base, which contain platinum or palladium as hydrogenating metals, and in which these metals are highly dispersed, such catalysts are special because of their high activity for hydrocarbon conversion reactions coveted, the activity being based on an atomic ratio II: Pt b £ where H: rd of at least a, 5 s 1 is based. As a result of this high atomic ratio, the oxidation of ammonia occurs catalyzed to a high degree and consequently is a control according to the invention the calcination stage is particularly necessary.

The degree of metal dispersion of a platinum or palladium containing The atomic ratio of H: Pt or

H s Pd are expressed which are determined by hydrogen chemisorption wird0 The highest activity is at atomic ratios a 1 Pt or H t Pd of 1 t 1 achieved, the noble metal on the carrier material having a maximum degree of dispersion A correspondingly lower dispersion leads to atomic ratios from H: Pt and H: Pd are less than 1: 1 and the catalyst activity is accordingly lower. A low degree of dispersion of the metal on the carrier material can also be of the sintering of the metal due to overheating during the calcination treatment originate.

The technique of hydrogen hemisorption is discussed below References explained: "J. Catalysis" 1 (1962), page 336 and in "J. Catalysis" 10 (1968), p. 224.

It has already been pointed out above that the inventive Controlled calcination leads to better kata-lyzers if in the course of the Manufacture of the zeolite catalyst ammonia or ammonium ions have been used sind0 In the following explanation it is indicated in each case in which stages Ammonia or salts derived from ammonia can be used. Instead of Ammonia can also be hydrazine, hydroxylamine or N-alkyl-substituted ammonia compounds be used, for example tetramethyl or tetraethylammonium hydroxide. In the context of the invention, the term “ammonia” also includes such ammonia derivatives Understood.

To have a high degree of dispersion of the platinum or palladium To ensure the catalyst, the metals in question are preferably by means of a competitive ion exchange on and / or deposited in the zeolite material, This measure is used to advantage in particular when shaped zeolite catalysts, e.g. extrudates, pellets, Tablets or the like with these metals should be loaded. In the case of the competitive ion exchange, that is Platinum or Palladium: in the cationic form with others in the ion exchange solution ions present with regard to the exchangeable places on and / or in the zeolite material in competition.

The ammonium ion is particularly preferably used as a competition ion The platinum or palladium cations can be in the form of a wide variety of salts or Complexes are used0 Preferably, such cations are in the form of their Amine complexes are used, which are derived from ammonia or N-substituted ammonia compounds derive, for example alkylamines, alkenylpolyamines and hydroxylamines. Examples suitable compounds are as follows: tetramine platinum dichloride (Pt (NH3) 4Cl2), hexamine platinum tetrachloride (Pt (NH3) 6Cl4), di (ethylenediamine) platinum dichloride (Pt (NH2-C2H4-NH2) 2Cl2) and tetramine palladium dichloride (Pd (NH3) 4Cl2).

The platinum or palladium compound should be used in such amounts be that the finished catalyst contains 0.05 to 5.0 wt.% Of the noble metal.

The ammonium ions used in the ion exchange treatment can from ammonium salts, from mineral acids or lower organic acids with Derive up to 10 carbon atoms in the Molectile, for example, are suitable as such salts ammonium nitrate, ammonium sulfate, ammonium chloride, ammonium format, ammonium acetate and ammonium citrate. However, salts are preferred used which leave no acid group in the calcined catalyst. The competition should be present in a large excess compared to the Elelmetall, thus the latter deposited in finely divided and homogeneous form on and / or in the zeolite material As a rule, the ion ratio between the competitive ion and the Noble metal ion at least 10: 1 and preferably this ratio is in the range of about 100: 1 and above. Very good results have been achieved with solutions. which the competitive ion in concentrations of at least 0.7 molar and preferably 1 to 2 molar included.

In order to achieve high atomic ratios H: Pt or H: Pd, it is a matter of course Proven to be very advantageous, the zeolite material before loading with the hydrogenating to neutralize effective metal.

This neutralization treatment offers particular benefits when there is formed zeolite material such as extrudates, pellets and tablets of zeolite type Y and mordenite is a. For such a neutralization the zeolite material in contact with ammonia or an organic nitrogen base brought, preferably together with ammonium ions. The zeolite material to be neutralized is then in water or a dilute aqueous solution of an ammonium salt suspended and ammonia or some other nitrogenous base are so often added to the suspension added until the pH value of the same no longer changes and remains constant. Preferably the zeolite material is neutralized to a pH of 7, though results can also be obtained beforehand1 if one at the Neutralization establishes a pH value in the range of 6 - 8.

Ammonia and / or ammonium ions can also be used to reduce the alkali metal content by ion exchange and treatment of the zeolite material or alkaline earth metal of the same. For this purpose, the zeolite material eluted in a percolation column with an ammonium salt solution until in the effluent ker alkali metal or alkaline earth metal ions can be determined more. That Zeolite material can also be heated several times with a fresh ammonium salt solution will.

The last-mentioned embodiment is preferably with an or several stages of calcination (temperature of 500 ° C or above) combined to a zeolite Y with a reduced alkali metal content of less than 1% by weight, calculated as alkali metal oxide.

The ammonia can also originate from the binder, which fEr the manufacture of molded zeolite tubes is used. For catalyst production Clays are often used as binders0 They often contain metal ions, which present adsorbed in the clay and can be replaced by other ions. Such Exchangeable clays containing metal ions often contain calcium, magnesium, potassium and sodium ions, i.e. very generally alkali metal and / or alkaline earth metal ions.

Such metal ions, however, interfere with the catalyst activity of the formed catalyst when such a clay is used as a binder is applied0 As a result, the interfering ions of the sound are replaced by non-interfering Replaced ammonium ions. A replacement for the exchangeable metal ions The clay can be made by treating the latter with an aqueous solution of an ammonium compound treated0 For the sake of simplicity, a clay treated in this way becomes free or is practically free from interfering metal ions, hereinafter referred to as clay in the ammonium form designated.

Clays which after conversion to the ammonium form for use Suitable binders are given below: attapulgite, sepiolite, Palygorskite, halloysite, montmorillonite, vermioulite, illite and ohlorite. Tone of the Kaolinite type Kaolins are also known by other names, for example as plastic clay from Devon and Dorset, as shame clay, paper clay and clay for covering purposes. Commercially available clays with these names are usually mii; others Silicate types defiled, for example with quartz and glinmer, but has the presence Certain amounts of such impurities generally do not have a deleterious effect on the activity of the shaped catalyst particles.

A montmorillonite in the ammonium form is preferably used as the binder or a montmorillonite type clay used with an ammonium compound has been treated, for example an ammonium bentonite.

Such clays in the ammonium form can be obtained by the clay one or more times with an aqueous solution of an ammonium compound heated or by using it such a watery one Solution subjected to ion exchange treatment. Such treatment will preferably continued until the unwanted metal ions neither can be detected in the clay product itself in the aqueous solution used In principle, any organic or inorganic ammonium compound can be used can be used for the ammonium treatment of the clay described above For the sake of simplicity, however, an ammonium salt is preferably used, in particular a salt9 which is derived from a mineral acid, suitable ammonium salts are: ammonium nitrate, ammonium sulfate, ammonium chloride, ammonium bromide or ammonium phosphate. However, ammonium nitrate is preferably used. Also ammonium salts, which are derive from lower organic carboxylic acids, for example from formic acid, Acetic acid, valeric acid, oxalic acid, tartaric acid, citric acid, benzoic acid and The like, are suitable for this purpose. Ammonium hydroxide, hydroxylamine, Hydrazine or salts of the last two compounds mentioned as ammonium compounds are used0 N-substituted ammonium compounds are also suitable, such as N-mono, N-di, N-tri-, or N-tetraalkyl or -alkenylammonium salts.

Preference is given to N-substituted ammonium compounds in which the alkyl or alkenyl groups each contain fewer than 6 carbon atoms0 The one applied during the: treatment of the clay with a solution of an ammonium compound Pressure or temperature can within a very wide range vary. However, such treatment is preferably carried out at substantially atmospheric pressure and a temperature in the range of 50-120 ° C. Particularly preferred is to carry out the heat treatment at the base point of the treatment solution.

Also the concentration of the aqueous used for the treatment Solution of an ammonium compound can vary widely within a wide range0 In general the solution is normal in terms of ammonium ions 0.1 - 20, although stronger concentrated solutions are usable. Very gate results are with one one molar solution of ammonium nitrate has been obtained after treatment with the Ammonium compound, the clay modified in this way is separated from the solution and preferably Washed with distilled water until there are no more anions in the filtrate can be proven. The modified clay is then dried, if desired, although this is generally not necessary9 because it is during the subsequent processing the clay and the zeolite material are water or some other wetting liquid can be added to obtain a deformable paste.

The clay in the ammonium form is used in an amount of 5 - 75% by weight and preferably from 10-35% by weight. based on the finished shaped catalyst particles, as a binder. used.

Before the Katelysator particles are formed, that should be done Zeolite material and the modified clay binder are homogeneously mixed with each other. Such homogeneous mixing can take place in various ways, for example can mix the two components as a dry powder in a suitable mixer can be mixed and then the powder mixture in a dough mixer can be mixed with water to form a paste-like slurry, but Xan can Also mix the dry powder directly with water in a homogenizer to form a slurry to process. The homogeneously mixed slurry obtained in this way is then formed into parts in a known manner, for example by granulating, Manufacture of tablets, coating of tablets, extrusion, pouring or Dripping, rolling in rotating drums and the like 0 The molded particles are then dried and then to increase mechanical strength calcined.

The formed particles can be of any desired size and shape Shape, for example, it can be pearls, balls, pills, tablets, briquettes, Act granulates and the like.

For use as a catalyst, the particles usually have Granulate form with a diameter of at least 0.5 mm or cylinders of 3 mm length.

During the calcination treatment, the clay and zeolite, both in the ammonium form, converted into the hydrogen form and simultaneously decomposes the existing metal amine complexes.

The use of a clay in the ammonium form as a binder is not only of importance for the zeolite material described, but for the treatment of all conversion catalysts with a low sodium content. In the preparation of of catalysts for hydrocarbon conversion is usually a calcination treatment carried out. Thereby it forms due to the presence of a clay in the ammonium form free ammonia, and therefore the controlled oxidative calcination according to the invention also recommended for the treatment of all conversion catalysts which have a tone contained in the ammonium form0 For the purposes of the present invention, a Zeolite material treated with ammonia and / or ammonium compounds as NH4 zeolite designated. The temperature at which the decomposition of such an NH4'-zeolite The type of zeolite material used depends on the type of decomposition of the NH4 zeolite Y starts, for example, at around 250 ° C, while an NH4 mordenite only begins to decompose at around 350 ° C.

In general, however, it can be said that the first calcination temperature for most types of zeolites is in the range of 200-400 ° C.

The final calcination temperature is for all zeolite types which are calcined are more or less the same and is generally between 400 and 900 0CO In this regard, it must be taken into account that metal hydrosilicates of the zeolite type above a certain maximum temperature, generally thermally unstable be or deactivated, the value being the maximum temperature for each Zeolite type is different.

For example, mordenite becomes thermal at temperatures above 650 ° C deactivated, while zeolite Y is only thermally unstable at temperatures above 850 ° C will0 Platinum and palladium containing zeolites are preferably at a temperature subjected to final calcination in the range of 475 - 650 ° C. Calcination temperatures from about 500-600 ° C. are particularly preferred.

The person skilled in the art can easily determine the first calcination temperature by means of an apparatus for thermal differential analysis or a thermogravimetric analysis Determine the weight. The time during which the zeolite material is at this first desination temperature should be held depends on several factors, such as size the amount of zeolite to be calcined, whether the material is during calcination spread in a thin layer or not, as well as whether practically all of it Zeolite material in which the ammonium form has been converted, which leaves the treatment time Easily determined experimentally In general, the zeolite material will be at least From the above held for 15 minutes at the first calcination temperature Explanation it will be seen that it is of more importance that with metal Loaded zeolite material must be kept at the first calcination temperature.

During the calcination treatment, therefore, the temperature becomes the Sample pre-recorded continuously and as soon as the If the temperature of the zeolite material rises rapidly, it is cooled by increasing the gas flow about the zeolite material.

Such an action can be carried out by either keeps the supply of oxygen or gas containing free oxygen constant, or by reducing this inflow and at the same time feeding in a stream of inert gas Nitrogen is preferably used as the inert gas. But you can have such a cooling also achieve by stopping the supply of oxygen or containing free oxygen Gas increased. The two measures explained first both lead to cooling of the zeolite material as well as a reduction in the oxygen content in the Treatment gas. The last-mentioned measure also leads to a cooling off of the material to be calcined, although the amount of oxygen is initially increased.

By regulating the gas flow over the zeolite material during During the first stage of calcination, the temperature can be determined in the described whiteness regulate the material well.

During the preferably gradual heating of the zeolite material At the first calcination temperature, air can be used as the oxygen-containing gas 0 At the beginning, the oxygen content of the oxygen-containing gas can be 20% by volume or even more. As soon as the first calcination temperature is reached, one reduces the oxygen supply per unit of time, if necessary the whole Oxygen supply and @supports inert gas at the same time or the gas flow becomes overall exalted. These gas flows are in the required manner regulated, depending on the temperature released during the first calcination temperature However, if one calcines zeolites containing platinum or palladium, it is It is essential to keep the oxygen content as high as possible in order to create highly active catalysts su get. In any case, an oxidative atmosphere should be maintained stay.

As soon as the temperature is increased to the final calcination temperature is, preferably again gradually, the oxygen content of the gas is not more iitisch0 The calcination in.

the final stage can be in the usual way in a stream of air or Oxygen are carried out. The controlled calcination according to the invention is preferably carried out in such a way that a temperature rise of the zeolite material during the calcination stage via the Tempehinaus temperature of the final calcination stage / practically is prevented, the controlled calcination is preferably carried out in such a way that that the material temperature is practically constant during the first calcination stage However, this means that the amount of heat carried by the inflowing gases should practically correspond to the heat generated.

No special Values are accurate because they depend on many factors, for example the amount of the material to be calcined, whether this material is spread out in a thin layer is or is not of the type of furnace used, of the material of construction of the furnace and the same. However, it is suitable for those skilled in the art not difficult, regulate the gas flow accordingly.

The invention is explained in more detail with reference to the drawings.

The temperature in ° C. is given on the abscissa.

In the figures, records of the heat released are shown, which by means of thermogravimetric analysis and thermal differential analysis obtained on micro samples of zeolite material treated with ammonium compounds have been.

These recordings clearly show the occurrence of an exothermic Reaction, where the maximum of the curve produced by the reaction is the first calcination temperature determined by the inventive method.

Fig. 1 shows a block diagram, which by means of a thermogravimetric Dare is obtained when heating NH4-Mordenite in air. It's the weight losses applied, which occur at every temperature level of 40 ° C. The decomposition of the NH4 zeolite starts slowly below 600 ° C. Fig. 2 shows a block diagram, which occurs when heating a plate with an ammoniacal / chloride solution obtained impregnated mordenite in air using a thermogravimetric balance will.

The decomposition of the platinum-containing NH4 zeolite takes place between 360 and 520 ° C.

Fig. 3 shows the recording of the heat of reaction generated upon heating an NH4-mordenite impregnated with an ammoniacal solution of platinum chloride is preserved in air. For the record is a device used for differential thermal analysis (reference compound: α-Al2O3). The exothermic maximum is 360 ° C and the first calcination temperature is preferably chosen somewhat below this maximum.

Pig.3 4 shows the recording of a differential thermal analysis of the same material as Fig. 3 but using NH4 mordenite as a reference component.

Fig. 5 shows the thermal behavior of an ammoniacal platinum chloride solution impregnated NH. - Zeolite Y in differential thermal analysis in air (reference compound : α-Al2O3).

The decomposition takes place in the range between 240 and 470 0C and it becomes a broad exothermic effect was observed, which begins and subsided at about 250 ° C extends to about 450 ° C.

FIG. 6 shows the recording of the thermal behavior of the analyzed in FIG. 5 Materials and explains the thermal release of ammonia in a nitrogen atmosphere. The maximum amount of ammonia is released at around 900 oC. Total will be about 3.96 wt.% ammonia formed.

A comparison of Figure 2 and 6 shows that when calcining a precious metal-containing NH4-Zeclits Y in air the exothermic oxidation of ammonia more difficult control ru is than in the case of a corresponding metal-loaded NH4-mordenite, because the rapid thermal decomposition of the first-mentioned material is significant takes place at a lower temperature, As can be seen from the above results, the recordings have been obtained on microsamples. For the large-scale The method according to the invention can be carried out, for example, as follows Duty cycle used: (a) Heating the treated with ammonium and using Noble metal-laden zeolite material within a period of at least one Hour, preferably from 3-6 hours, to the first calcination temperature; (b) Keeping the zeolite material at this temperature for at least 15 minutes, preferably for at least one hour, at the same time regulating the oxygen supply during process steps (a) and (b); (c) Increasing the tempo in the loudspeaker at least one hour, preferably from 2-5 hours, to the final calcination temperature and (d) calcining the material at that final temperature for at least one Hour, preferably for 2 to 6 hours.

Of course, a second step can be carried out before the final calcination or third calcination has been inserted. In general, however, it is not necessary if one strictly follows the Lohre of the present invention.

The zeolite-based catalysts produced according to the invention can can be used for a wide variety of hydrocarbon conversion processes, ' for example for hydrant cleavage, polymerization, alkylation and dealkylation, for reforming and isomerization. Loaded with precious metal However, mordenite-based catalysts are particularly suitable for isomerization of low hydrocarbons in the presence of hydrogen. In particular, can with such a noble metal catalyst any aliphatic hydrocarbon with at least 4 carbon atoms isl molecule to a corresponding, more highly branched one Hydrocarbon are converted. The catalysts in question are therefore particularly suitable for the isomerization of hydrocarbons with 5 to 10 carbon atoms as well as mixtures of such hydrocarbons0 are usually used as output material Hydrocarbons or hydrocarbon mixtures boiling only below about 600 ° C used. Very suitable hydrocarbon starting mixtures are those made from petroleum ge.-recovered the ect-distilled fractions, which hydrocarbons with 4 - Contains 7 carbon atoms If hydrogen is also used to deactivate To prevent the catalyst, it is also possible to add hydrocarbon mixtures which contain elefinic hydrocarbons, since during isomerization the unsaturated compounds are converted into the corresponding isoparaffins, In a corresponding manner, the alkyl and 'alkenyl groups of alkyl and Alkenyl aromatics are isomerized and, if desired, hydrogenated0 In addition, st it possible9 naphthenic Isomerize compounds.

Such isomerization treatment is preferably carried out in a Temperature in the range from 200 to 400 ° C and in particular from 225 to 350 ° C carried out. . The hydrogen partial pressure can vary between 3 and 70 kg / cm² and is preferably between 10 and 50 kg / cm². The space velocity can be in the range from 0.5 to 10 liters of hydrocarbon feed per liter of catalyst per hour vary and the gas velocity is generally 50 - 500 normal liters Hydrogen per kg of starting material.

Precious metal loaded aluminosilicate zeolites with a molar ratio SiO2: Al2O3 between 3: 1 and 6.5: 1 are particularly suitable as catalysts for the hydrogenative cleavage, it such catalysts can be any Hydrocarbon oils can be split by hydrogenation. Hydrocarbon oils can be used as the starting material be used in the range from light petrol to heavy destillate, and They can be obtained by direct distillation or by vacuum distillation of crude oils or by processing such oils as are commonly used in the oil industry takes place. Such processes can be a thermal, catalytic or hydrogenative cleavage, for platforming, for viscosity breaking, deasphalting, removing asphaltenes or any combination thereof Take action. Such catalysts based on aluminosilicates can also for the single-stage hydrogenative cleavage of hydrocarbon oils with Boiling points below 350 0Ü are used, for example from scht: Jeren Gasölen, Middle distillates, such as kerosene and light gas oils, as well as naphthas, whereby Gas components for liquid gas and within the gasoline boiling range (65 - 180 ° C ASTM) boiling hydrocarbon oil fractions are obtained because such catalysts maintain their activity even in the presence of nitrogen compounds it is also used to advantage in a one-step hydrogenation cracking process are, with catalyst beds ven other catalysts for the hydrogenative cleavage of hydrocarbon oils which boil essentially above 350 ° ¢, for example from heavy flashed distillates and deasphalted residual hydrocarbons fabric oils. For this purpose, the heavy oils in question will initially be handled by a suitable catalyst to give oil fractions hydrogenated split, which practically below Boil 350 ° C, for example in the presence of a highly fluorinated tungsten and nickel containing aluminum oxide catalyst, or one containing tungsten and nickel Silica-aluminum oxide catalyst with a high aluminum content (approx. 25% by weight Aluminum oxide). These oil fractions are then sent without further purification or fractionation by means of catalysts prepared according to the invention on the Treated based on aluminosilicates0 Then the hydrogenated material is split fractionated and a material boiling above the gasoline boiling range is in of the reactor. Instead of a few Reaktois can of course two or more reactors connected in series can also be used, the Hydrogen cleavage is preferably carried out at a hydrogen partial pressure of 30 - 200 kg / cm² and a temperature of 250 - 450 ° C. Temperature and Pressures can be chosen to be relatively low and the results are satisfactory with temperatures between 275 and 390 0C and with hydrogen partial pressures between 50 and 100 kg / cm² have been achieved.

The space velocity can range from 2 to 10 liters of hydrocarbon oil per liter of catalyst per hour and the gas velocity can be in the range from 250 to 5000 normal liters of hydrogen per kg of starting material can be selected.

The zeolite catalysts loaded with noble metal are reduced in the Form used for the isomerization and hydrogenation splitting of the hydrocarbons.

Example 1 Ex, 1 kg of NH4 mordenite is produced by initially adding synthetic powdery mordenite with a two-molar aqueous hydrochloric acid solution treated, as the mordenite washes with deionized water and by means of a In molar ammonium nitrate aqueous solution subjected to ion exchange treatment. The NH4 mordenite obtained in this way is then ion-exchanged with an ammoniacal Treated platinum chloride solution, which contains 1.44 g Pt / liter (2.5 liter solution per kg of mordenite, calculated on a dry basis). The slurry is heated to 50 ° C and kept at this temperature for several hours with stirring. Subsequent will the supernatant liquid is decanted off and the zeolite material washed with one liter of deionized water per kg of mordenite0 The one with platinum Loaded mordenite is placed in a tube furnace equipped with multiple thermocouples is dried in flowing air at 120 ° C. After a drying time of 4 hours the temperature is increased to 350 ° C (temperature of the material) and the temperature is kept by increasing the gas flow through the furnace, stant / by each introduces nitrogen when the temperature recorded by the thermocouples the sample begins to rise rapidly. After getting the temperature one more Has held at 350 ° C for an hour, it is increased to 510 ° C within 4 hours and then held at this value for 3 hours. The finished catalyst shows one high isomerization activity with n-pentane. That determined by hydrogen chemisorption Atomic ratio H t Pt is 0.6.

Example 2 Using commercially available Nordenite extrudates with a particle size of 1.587 mm is a molded mordenite catalyst produced0 1 kg of mordenite extrudates with a sodium content of 7.0% by weight Na2O initially together with 10 liters of an aqueous two-molar hydrochloric acid solution heated to about 100 ° C. It is then washed with deionized water and heated three more times for one hour each time at about 100 ° C with an aqueous one-molar Ammonium nitrate solution, each time a fresh one Solution in one Amount of 1 liter of solution per 100 g of mordenite is used. That way Mordenite loaded with ammonium in ion exchange is mixed with deionized water washed and dried at 120 ° C.

The dried shaped catalyst particles become through competitive ion exchange loaded with platinum. For this purpose 1 kg of the dried mordenite is used at room temperature suspended in a two-molar ammonium nitrate solution (0.25 liter solution per 100 g mordenite). This suspension is by means of 28% strength by weight aqueous ammonia to neutralized to a pH value of 70 By adding more ammonia, the The pH of the slurry is repeatedly adjusted to this value until it is at least remains constant for an hour. Then an aqueous solution of Pt (NH3) 4Cl2 added to the slurry (23 g Pt / liter solution). The platinum comes in one Excess of 30 ffi compared to the theoretically required amount applied which gives a platinum content of 0.4% by weight on the finished catalyst. While the addition of the platinum-containing solution, the slurry is stirred and one the stirring continues for a further 8 hours while the temperature is kept at 50 0O wird0 Then the supernatant liquid is decanted and the formed Catalyst particles are washed with deionized water and then washed at 120 ° C dried.

The ones with platinum. laden mordenite particles are pouring in air calcined. The mordenite comes in one with multiple thermocouples equipped Oven spread out in a thin layer of 4 mm. The temperature will slowly increase up to 350 OO increased (measured in the material) and then kept as precisely as possible at this value, by increasing the airflow every time the thermocouples take a quick start Show rise in material temperature. The temperature will rise for an hour Maintained 350 ° C iflid then it is increased to 510 ° C within 4 hours, after which it is held at this value for three hours.

The finished catalyst has an Na2O content of 0.15% by weight Platinum of 0.36 wt.% And it has an atomic ratio H: Pt of 0.8, determined by Hydrogen chemisorption, to 0 Example 3 Starting from a powdery mordenite, a mordenite-based catalyst is produced in the form of shaped particles, 350 g of a commercially available mordenite powder with an average Particle size of 5 microns will be along with 3.5 liters of one for one hour boiled two molar aqueous hydrochloric acid solution. The powder is then filtered off and washed with one liter of deionized water, then the mordenite through Treatment in a percolation column with an aqueous one molar ammonium nitrate solution Converted to the ammonium form at room temperature The treatment will last so long continued until the abbot usa is frqi of sodium ions.

The thus obtained NH4-Nordenit with a sodium content of 0.04 % By weight Na2O is then washed with deionized water and again in deionized water Slurried water (0.5 liters of water per 100 g of powder), add to this slurry with a pH of about 4, 26.9 ml of an aqueous solution are added with stirring of Pt (NH5) 4Cl2 added. This treatment solution contains 29 mg platinum;) e mlO The slurry is stirred for at least half an hour, then filtered and dries the mordenite powder at 120 ° C.

The mordenite powder is mixed with 85 g of ammonium bentonite in a ball mill ground and then 525 g of water are added to the dry powder mixture. Milling is continued until an extrudable paste is obtained. This paste becomes pressed into 3 mm extrudates, which are dried at 120 ° C. The ammonium bentonite is obtained as follows: Commercially available bentonite is boiled one each time In an aqueous two molar ammonium nitrate solution (one liter solution 100 g bentonite each). The NH4 bentonite obtained in this way is then filtered off with deionized Washed with water and dried at 120 ° C.

The dried extrudates are illustrated in Example 2 Way calcined. The finished catalyst contains 0.4% by weight of platinum and has a atomic H: Pt ratio of 0.6.

It contains about 20% by weight of the bentonite binder.

The activity of the catalyst obtained in this way is measured in a standard test by means of the isomerization of n-pentane under the following conditions tested t temperature 250 ° C, pressure 30 kg / cm², space velocity 1 g n-pentene each g of catalyst per hour, molar ratio of H2: n-pentane 2.5.

Before carrying out the experiment, the catalyst is placed in a hydrogen atmosphere reduced at 500 ° C.

The results obtained are in the table below summarized: Table I Composition of the reaction product after 2 hours after 19 hours

<0d5 'wt% 2.0 2.2 i-05, n 65t1 62.5 n-C5' "32.9 35.3 Example 4 This example explains the influence of the controlled calcination according to the invention on the isomerization activity of the catalyst.

According to Example 2, samples of a non-calcined, with platinum Beledenen, molded mordenite catalyst produced containing 0.4 wt. Platinum. This molded catalyst is made according to different methods calcined.] In experiments nos. 1 and 2, the shaped catalyst is more conventional Calcined manner, with the zeolite material slowly increasing to a calcining temperature is heated by about 500 ° C. In experiments no. 3 and 4, a step-shaped one is used Calcination carried out durably, but at the first calcination temperature of 350 ° C there is no strict temperature control. In experiment no. 5, the exothermic heating effect is used controlled by feeding in nitrogen according to Example 1. At the attempton 1-4 a muffle furnace is used, while in experiment 5 a tubular furnace, as is customary is used for catalyst regeneration.

The effect of the calcination measures on the atomic ratio H : Pt is shown in Table II below.

The thus calcined frozen catalyst particles are used for used the isomerization of n-hexane. For this, the catalysts are used first carefully reduced with hydrogen in the following manner: Before introduction The extrudates are allowed to enter the reactor in equilibrium with the water content the air laden with moisture. The catalyst is then used of 560 normal liters of hydrogen per liter of catalyst per hour with an absolute Pressure of 30 kg / cm² and a temperature between 250 and 350 ° C for one hour reduced.

Following this reduction, the temperature is lowered to 240 ° C, and then passing n-hexane into the reactor at hourly space velocity of 2 g of n-hexane per g of catalyst per hour and using a hydrogen: n-hexane molar ratio of 2.5. Under these conditions the n-hexane conversion shown in the table below is explained.

Table II Con Atom Con Conversion such calcination treatment ratio of n-hexane No. H: Pt wt.% 1 3 hours at 500 ° C, 3 hours at 500 ° C; thick material layer (250 g) 0.12 29.5 2 moist sample at 500 ° C in the Furnace introduced, 3 hours at 500,000 (5 g) 0.16 44.0 3 2 hours at 350 00, 2 hours at 350 ° C, 1 hour at 500 ° C, 1 hour, at 500 ° C; thick material layer (250 g) 0.29 49.8 4 2 hours at 350 00, 2 hours at 350 ° C, 1 hour at 500 ° C, 1.5 hours at 500 ° C; slim@ @. Layer of material (250 g) 0.44 52.2 2 hours at 350 ° C, 1.5 hours at 350 ° C, 2 hours at 500 ° C, 5 hours at 500 ° C; Temperature- increase during calcinations- 0.52 54.3 treatment at 350 ° C by conduct nitrogen under- presses (200 g) The above data confirm that the calcination treatment according to the invention leads to highly active isomerization catalysts, as shown by the atomic ratio H t Pt and the percentage conversion.

Example 5 This example explains the influences of the invention Working method for the production of noble metal loaded zeolite catalysts, both in terms of metal distribution and isomerization activity of the finished catalyst.

According to Example 2, mordenite extrudates of 9 mm with a low Sodium content produced. These are made according to various methods using tetramine-platinum compounds loaded. After a final calcination carried out for 3 hours at 500 ° C the catalysts thus obtained are in a microflow reactor with respect to checked their isomerization activity. The catalysts are previously using Reduced hydrogen at 250 ° C and a pressure of 30 kg / cm².

The feed material for the isomerization is n-penteab die Isomerization is carried out under the following conditions: temperature 250 ° C, Pressure 30 kg / cm², molar ratio hydrogen: n-pentane 2.5: 1, hourly space velocity 1 g of n-pentane per g of catalyst per hour. The results achieved are in summarized in the table below.

Table III Pt content i-pentam of the content of Catalyst loading of the Pt distribution reaction shaped catalytic converter product, % By weight (viauell)% by weight 0.5 ion exchange with Pt (NH3) 4 (NO3) 2 inhomogeneous 44 - 46 0.5 impregnation with Pt (NH3) 4Cl2 inhomogeneous 40 - 41 1.0 ion exchange with a solution of Pt (NH3) 4 (NO3) 2, the 1 mole of NH4NO3 per liter contains almost (see example 2) homogeneous 55 0.37 ion exchange with a solution of Pt (NH3) 4Cl2, the 2 moles of NH4NO3 per liter contains (see example 2) homogeneous 58 Example 6 This example explains the influence of an excessively high final calcination temperature on the platinum dispersion and the activity of the finished catalyst.

According to Example 3, mordenite powder is mixed with an aqueous hydrochloric acid solution and pretreated with an aqueous ammonium nitrate solution, thereby reducing the sodium content is reduced to 0.04 wt.% Na2O. The modified mordenite powder is with 0.36% by weight of platinum using the competitive ion exchange method according to the example 2 loaded. The material then undergoes a controlled calcination at an initial stage Calcination temperature of 350 ° C and a final calcination at one temperature Subjected by 510 oO. The catalyst obtained has an atomic H: Pt ratio of 0.94. Part of the catalyst is carefully at 250 ° C and a pressure of 30 kg / cm² reduced with hydrogen. After the reduction treatment, it becomes n-pentane fed and isomerized at the same temperature and pressure, w @ at an hourly space velocity of 1 g of n-pentane per g of catalyst per hour is applied. The molar ratio of hydrogen to starting material is 22.5 Thereby 68 are converted into isopentane.

Another part of the calcined catalyst is calcined again namely for 3 hours at 650 ° C. The atomic ratio H: Pt of the re-calcined Catalyst is 0.08.

The catalyst is in the reduced porm for the isomerization used under the above conditions and the conversion of n-pentene to isopentane is only 40%.

Example 7 Starting from a commercially available powdery one Zeolite Y, a faujasite-based catalyst is produced in the form of particles.

By treating a commercially available powdered zeolite Y, which consists in repeating the powder several times with fresh two-molar ammonium nitrate solution heated, the powder then calcined (temperature 550 ° C) and the calcined The material can be heated again with a fresh one-molar ammonium nitrate solution 0.76 kg of a decationized zeolite Y of low alkali metal content was obtained (0.3% by weight Na2O, water content about 21.0% by weight). The catalyst is in 1.5 liters slurried a 2 molar ammonium nitrate solution.

The pH of the solution is adjusted by adding concentrated 28% by weight Adjust ammonia to about 7 and add more ammonia solution until the pH remains constant at this value for one hour0 to this slurry 130 ml of a solution containing Pd (NH3) 4 (NO3) 3 are then added, which 30 mg palladium per ml contains. The solution is added while stirring. One stirs Another 16 hours at a temperature of 50 ° C, then filtered the solid Material off, washed with deionized water and dried at 120 ° C.

The loaded with palladium Y zeolite is in a ball mill for 30 minutes long mixed with 985 g of ammonium bentonite (water content about 8.6% by weight). The bentonite in which ammonium ferm is. according to the procedure of Example 3 was obtained.

Then 1.6 liters of deionized water are added Through further grinding, it becomes a paste that can be pressed out.

This paste is pressed into particles of 3 mm, which at 120 ° C to be dried.

The pressed particles are at a first calcination temperature of 250 ° C under control of the temperature of the material to be treated and finally calcined The finished catalyst has an Na — O content, which has been treated at 500 ° for 3 hours of 0.2% by weight and a palladium content of 0.2% by weight.

It contains about 56.4% by weight of the bentonite binder.

Patent claims:

Claims (1)

Claims 1. A method for producing a catalyst mater Use of a metal hydrosilioate of the zeolite type, the carrier material treated with ammonia and X or ammonium ions during catalyst production, is loaded with one or more metals with a hydrogenating effect and calcined, d u r c h e k e n n n z e i c h n e t that the calcination in the presence of oxygen edr one containing free oxygen. Gas in controlled Way is carried out in such a way that the catalyst is controlled by regulating the gas flow to a first calcination temperature and in a further treatment stage the final calcination temperature is heated. 2. The method according to claim 1, characterized in characterized that the first calcination temperature is in the range of 200 - 400 oC is, 3. The method according to claim 1 and 2. characterized in that the final calcination temperature is in the range of 400-900 oO, preferably in the range of 500-600 oO. .4o method according to claim 1 - 3, characterized in that the Gas flow is increased as soon as the temperature of the zeolite material rises sharply. 5. The method according to claim 4, characterized in that the supply of the oxygen or the gas containing free oxygen is either constant is maintained or reduced, and that at the same time a flow of an inert gas, preferably nitrogen, is fed in. 6. The method according to claim 4, characterized in that characterized in that the space velocity; Lt of oxygen and free oxygen containing en gas is increased. 7. The method according to claim 1-6, characterized in that as free Oxygen-containing gas air is used, 8. The method according to claims 1-7, characterized in that a temperature rise of the zeolite material during the first calcination stage to a temperature above the final calcination temperature is prevented. 9. The method according to claim 8, characterized in that the temperature of the zeolite material is kept practically constant. 10. The method according to claims 1-9, characterized in that as Metal hydrosilicate an aluminosilicate of the zeelite type, preferably an aluminosilicate with a molar ratio of silica to aluminum oxide of at least 3: 1, is particular mordenite is used0 11. The method according to claim 1-10, characterized in that the metal with a hydrogenating effect is a representative the platinum group, preferably platinum or palladium, is used. 12. The method according to claim 11, characterized in that the platinum or palladium by means of a competitive ion exchange treatment on and / or is precipitated in the zeolite material, preferably ammonium ions as competing ions serve. 13G method according to claim 1 - 12, characterized in that the Zeolite material before loading with the hydrogenating metal by means of ammonia is neutralized, 14o method according to claim 13, characterized in that the zeolite material for neutralization in water or an aqueous solution of an ammonium salt suspended and that as long as monia to this suspension is added until the pH value thereof no longer changes and becomes constant remains at a value of about 7. '150 The method according to claims 1-14, characterized in that the alkali metal or alkaline earth metal content of the zeolite material by treatment is reduced with ammonia and / or ammonium ions. 16. The method according to claim 1-15, characterized in that the Zeolite material is in the form of individual particles. 17. The method according to claim 1-16, characterized in that the Deformation of the zeolite material into particles using a clay binder takes place whose exchangeable metal ions have previously been replaced by ammonium ions are, preferably by means of a treatment with an aqueous solution of an ammonium compound. 18. The method according to claim 17, characterized in that the binder is preferably an NH4 bentonite and in an amount of 5 - 75% by weight, based on the finished molded particles, is used. 19. Use of a catalyst prepared according to claims 1-18 for the conversion of hydrocarbons. 20. Embodiment according to claim 19, characterized in that a. A mordenite-based catalyst loaded with a noble metal for isomerization of aliphatic hydrocarbons with at least 4 carbon atoms in the molecule at temperatures in the range of 200 - 400 ° C, hydrogen partial pressures in the range from 3 - 70 kg / cm² and space velocities in the range from 0.5 to 10 liters of hydrocarbon feedstock per liter of catalyst per hour and a gas supply of 50 - 500 normal liters of hydrogen per kg of feed material is used. 21. Embodiment according to claim 19, characterized in that the an aluminosilicate loaded with a noble metal Zeolite with a molar SiO2: Al2O3 ratio between 3: 1 and 6.5: 1 for hydrogenating cleavage of a hydrocarbon oil at a temperature in the range of 250 - 450 ° C. a hydrogen partial pressure of 30-200 kg / cm2, a space velocity from 0.2 - 10 liters of hydrocarbon oil per liter of catalyst per hour and one Gas supply of 250 - 5000 normal liters of hydrogen per kg of feed material used becomes0 L e r s e i t e