DE19805719A1 - Array of heterogeneous catalysts, or precursors, each arranged in separate channel, used to screen for activity, selectivity or long-term stability - Google Patents

Abstract

Array of heterogeneous catalysts and/or their precursors (A) comprises a body having at least n channels, preferably arranged in parallel, passing through it, with n different (A) present in the channels (n is at least 2, preferably 10 and especially 10000). An Independent claim is also included for preparation of these arrays.

Description

The invention relates to a method for combinatorial production and Testing of heterogeneous catalysts and obtained by this method Catalysts.

Has to manufacture and study new chemical compounds in addition to classic chemistry, based on synthesis and investigation single substances is directed, the so-called combinatorial chemistry developed. A large number of reactants were initially combined in one One-pot synthesis implemented and examined whether the resulting reaction mix the desired properties, for example a pharmacological Effectiveness, showed. Has been an efficacy for such a response found mixture, which had to be determined in a further step special substance in the reaction mixture responsible for the effectiveness was. In addition to the high effort to determine the actually active Connection was also difficult with a variety of reactants to rule out undesirable side reactions.

Another approach to combinatorial synthesis is syn thesis of a multitude of compounds through targeted dosing and conversion attracting a range of reactants in a variety of different Reaction vessels. This method preferably lies in every reak  tion vessel a reaction product before, so that, for example, given pharmacological efficacy of a mixture used in its manufacture used starting materials are known immediately.

In addition to the first applications of this more specific combinatorial synthesis in the search for new pharmacologically active substances in recent times the synthetic process has also been extended to low molecular organic compounds as well as organic and inorganic Catalysts.

In F.M. Menger et al, "Phosphatase Catalysis Developed via Combinatorial Organic Chemistry ", J. Org. Chem. 1995, 60, pages 6666 to 6667 Production of organic catalysts using combinatorial processes described. On a polyallylamine, 8 functiona lized different carboxylic acids bound. In addition, under different metal ions bound to the polymer via complex formation. The polymers obtained were then determined for their phosphatase activity examined. It is not described whether the catalysts after a automated manufacturing processes were obtained. It's just that Preparation of individual catalysts described.

In C.L. Hill, R.D. Gall, "The first combinatorially prepared and evalua ted inorganic catalysts. Polyoxometalates for the aerobic oxidation of the mustard analogous tetrahydrothiophene (THT) ", J. Mol. Catalysis A: Chemical 114 (1996), pages 103 to 111 is the combinatorial production and Testing of polyoxometalates for the aerobic oxidation of tetrahydrothio phen. The polyoxometalates were mixed by mixing under different proportions of metal salt solutions of the desired metals poses. For this purpose, tungstate, molybdate and vanadate solutions as well as a Sodium hydrogen phosphate solution prepared. After dosing the ent  speaking solutions, the pH was adjusted to a predetermined value discontinued and implemented. The catalysts obtained were used in solution for the implementation. It is not wrote whether the catalyst production was automated.

Process for the targeted dosing of different amounts of different liquid reactants in an array of reaction vessels, for example can resemble a spotted plate are described in US 5,449,754. To becomes the printhead of an inkjet printer that uses stock solutions from the Reactants is connected using an XY positioner over the array moved and the dispensing of the liquids controlled with a computer.

In F.C. Moathes et al, "Infrared Thermographic Screening of Combinatori al Libraries of Heterogeneous Catalysts ", Ind. Eng. Chem. Res. 1996, 35, 4801 to 4803 is the study of combinatorial libraries of heterogeneous catalysts described by IR analysis. The cat gates consisted of different element metals based on aluminum were applied oxide. They were in terms of catalytic activity of hydrogen oxidation is investigated. The individual catalysts were by soaking alumina pellets in appropriate metal salt solutions gen, drying and calcining. It is not specified whether the Manufactured automatically.

The different pellets were placed in predetermined places on one Carrier deposited and contacted with hydrogen under reaction conditions. During catalytic activity, the catalyst warmed up, and the Warming was measured using an infrared camera, which caused the active catalysts could be determined.  

In B.E. Baker et al, "Solution-Based Assembly of Metal Surfaces by Combinatorial Methods ", J. Am. Chem. Soc. 1996, 118, pages 8721 to 8722 is the production of metal with different compositions surfaces described by combinatorial methods. This will be a silane coated glass plate into a at a predetermined speed colloidal gold solution immersed, so that a gradient of the gold ver division on the substrate results. After removing and drying the plate if this is rotated by 90 ° and immersed in a silver ion solution, so that there is another concentration gradient on the plate. It results there is a continuous change in composition in the upper surface.

X.-D. Xiang et al., "A Cominatorial Approach for Materials Discovery", Science 268 (1995), pages 1738 to 1740 describe the production of BiSrCaCuO and YBaCuO superconductor films on substrates, whereby by physical masking and vapor deposition techniques at Deposition of the corresponding metals in a combinatorial array of different metal compositions is obtained. According to the Calci kidneys are located at different positions in the array Compositions before and can with micro probes, for example, on their Conductivity are examined.

WO 96/11878 describes the manufacture of such superconductor arrays also described the production of zeolites, being made of several metals salt solutions with an ink-jet the required quantities without priori Total mixing can be dosed on a kind of spotting plate, with addition the last solution uses a precipitation. The manufacture of BSCCO Superconducting can also be done by dosing the individual nitrate solutions separately of the required metals by spraying on a kind of spotted plate and followed by heating.  

With the known processes, different heterogeneous catalysts can be used getting produced. However, the testing of the catalysts is complex and can often not under realistic conditions, e.g. B. with the required Residence times of the reactants on the catalyst, because the catalysts for example on a larger, generally flat support are present and this, for example, with a gas mixture to be reacted must be loaded.

The object of the present invention is to provide a method for the production of arrays from inorganic heterogeneous catalysts or their precursors, in which the catalysts obtained with lower Effort and can be tested under conditions that are great technical processes are similar. In addition, the disadvantages are said to be the best existing systems can be avoided. Corresponding arrays should also be to be provided.

The object is achieved according to the invention by providing an array from, preferably inorganic, heterogeneous catalysts and / or their pre runners, made up of a body that, preferably parallel, continuous Has channels, in which at least n channels n different, preferred as inorganic, heterogeneous catalysts and / or their precursors ten, where n is 2, preferably 10, particularly preferably 100, in particular 1000, especially 10,000.

According to one embodiment of the invention, the body is a tube bundle reactor or heat exchanger, and the channels are pipes.

According to a further embodiment of the invention, the body is a Block made of a solid material, the channels, for example in the form of Bores.  

The heterogeneous catalysts and / or their precursors are preferred Full contacts or supported catalysts and / or their precursors and lie as catalyst bed, tube wall coating or auxiliary carrier coating in front.

The term "array of inorganic heterogeneous catalysts or their Forerunners "denotes an arrangement of different inorganic Heterogeneous catalysts or their precursors on predetermined, spatially areas of a body separated from one another, preferably a body with parallel continuous channels, preferably a tube bundle reactor or Heat exchanger. The geometric arrangement of the individual areas others can be chosen freely. For example, the areas in the form of a series (quasi one-dimensional) or a checkerboard pattern (quasi two-dimensional). For a body with parallel continuous channels, preferably a tube bundle reactor or heat exchanger with a large number of mutually parallel tubes, the arrangement in the Consideration of a cross-sectional area perpendicular to the longitudinal axis of the pipes clear: there is an area in which the individual pipe cross sections represent the different spaced apart areas. The Areas or pipes can - for example, for pipes with a circular Cross section - also available in a tight package, so that differ che rows of areas are arranged offset from each other.

The term "body" describes a three-dimensional object that has a plurality (at least n) of continuous channels. The canals thus connect two surface areas of the body and run through it Body through. The channels are preferably essentially, preferred completely parallel to each other. The body can consist of one or be constructed of several materials and be solid or hollow. He can have any suitable geometric shape. It preferably has two  mutually parallel surfaces, in each of which an opening of the Channels. The channels preferably run perpendicular to these surfaces. An example of such a body is a cuboid or cylinder in which the channels between two parallel surfaces run. However, a large number of similar geometries are also conceivable.

The term "channel" describes one that runs through the body Connection of two openings on the body surface, the for example, the passage of a fluid through the body. Of the Channel can have any geometry. He can do one over the Length of the channel variable cross-sectional area or preferably one have constant channel cross-sectional area. The channel cross section can be at for example an oval, round or polygonal outline with straight or have curved connections between the corner points of the polygon. A round or equilateral polygonal cross section is preferred. All channels in the body preferably have the same geometry (cross cut and length) and run parallel to each other.

The terms "tube bundle reactor" and "heat exchanger" describe together set parallel arrangements of a plurality of channels in the form of Pipes, the pipes can have any cross section. The pipes are arranged in a fixed spatial relationship to each other, are preferably spaced apart from one another and are preferred wise surrounded by a jacket that covers all pipes. This can for example, a heating or cooling medium is passed through the jacket, so that all pipes are tempered evenly.

The term "block made of a solid material" describes a body a solid material (which in turn consists of one or more starting materials materials can be built), the channels, for example in the form of  Bores. The geometry of the channels (holes) can be like can be freely selected as described above for the channels. The Channels (holes) do not have to be drilled, but rather can, for example, also when molding the solid body / block by extrusion of an organic and / or inorganic molding compound, can be left out (for example by means of an appropriate nozzle geometry during extrusion). In contrast to the tube bundle reactors or heat The space in the body between the channels in the block is exchanged always filled in by the solid material. The block is preferably out one or more metals.

The term "predetermined" means that, for example, a row under different catalysts or catalyst precursors in this way in a tube well delreaktor or heat exchanger is introduced that the assignment of different catalysts or catalyst precursors to the individual Pipes is recorded and later, for example, in determining the Activity, selectivity and / or long-term stability of the individual catalysts can be retrieved to provide a unique association for certain To enable measured values for certain catalyst compositions. The catalysts or are preferably produced and distributed their precursors to the different tubes of the tube bundle reactor computer controlled, the respective composition of a catalyst and the position of the tube in the tube bundle reactor into which the catalyst or catalyst precursor is introduced, is stored in the computer and can be called up later. The term "predetermined" thus serves the distinction from a random or statistical distribution the generally different catalysts or catalyst precursors on the tubes of a tube bundle reactor.  

The production of the arrays according to the invention from, preferably inorganic rule, heterogeneous catalysts and / or their precursors can under Different procedures take place:

Method a comprises the following steps:

• a1) Preparation of solutions, emulsions and / or dispersions of elements and / or element compounds in the catalytic converter tor and / or catalyst precursor present elements, and optionally of dispersions of inorganic carrier materials lie,
• a2) optionally adding adhesion promoters, binders, Viscosity regulators, pH regulators and / or solid organic carriers in the solutions, emulsions and / or Dispersions,
• a3) simultaneous or successive coating of the channels of the body with the solutions, emulsions and / or disper sions, in each channel a predetermined amount of Solutions, emulsions and / or dispersions are introduced, to obtain a predetermined composition, and
• a4) optionally heating the coated body, given if in the presence of inert or reactive gases, to a Temperature in the range of 20 to 1500 ° C for drying and optionally sintering or calcining the catalysts and / or catalyst precursors.

Method b comprises the following steps:

• b1) Preparation of solutions, emulsions and / or dispersions of elements and / or element compounds in the catalytic converter tor and / or catalyst precursor present elements, and optionally of dispersions of inorganic carrier materials lie,
• b2) if appropriate, adding adhesion promoters, binders, Viscosity regulators, pH regulators and / or solid organic carriers in the solutions, emulsions and / or Dispersions,
• b3) simultaneous or successive coating of in the Channels of the body present catalyst carriers with the Solutions, emulsions and / or dispersions, being in each Channel a predetermined amount of solutions, emulsions and / or dispersions is introduced to a predetermined Obtaining composition on the catalyst supports, and
• b4) optionally heating the body with the coated Catalyst supports in the channels, if appropriate in the presence of inert or reactive gases, to a temperature in the range from 20 to 1500 ° C for drying and optionally sintering or calcining the catalysts and / or catalyst runner.

The method c) comprises the following steps:

• c1) Preparation of solutions, emulsions and / or dispersions of elements and / or element connections in the cataly sator and / or catalyst precursor chemical present  Elements and optionally dispersions of inorganic Carrier materials,
• c2) Mixing predetermined amounts of the solutions, emulsions and / or dispersions and optionally precipitation aids average in one or more parallel reactions vessels,
• c3) if appropriate, adding adhesion promoters, binders, Viscosity regulators, pH regulators and / or solid organic carriers in the mixture (s) obtained,
• c4) coating one or more predetermined channels of the Body with the mixture or several mixtures,
• c5) repetition of steps c2) to c4) for other channels of the Body until the channels with the respectively predetermined Kataly sator and / or catalyst precursor compositions be are stratified,
• c6) optionally heating the coated body, given if in the presence of inert or reactive gases, to a Temperature in the range of 20 to 1500 ° C for drying and optionally sintering or calcining the catalysts and / or catalyst precursors.

It preferably comprises the following steps:

• c1) Manufacture of solutions of element connections in the Catalyst present chemical elements other than oxygen,  and optionally of dispersions of inorganic carrier materials rialien,
• c2) Mixing predetermined amounts of the solutions or wise dispersions and, where appropriate, precipitation aids in one or more reaction vessels operated in parallel precipitating the chemical present in the catalyst Elements,
• c3) if appropriate, adding adhesion promoters, binders, Viscosity regulators, pH regulators and / or solid organic carriers in the suspension obtained,
• c4) coating one or more predetermined tubes of the Tube bundle reactor or heat exchanger with the suspension,
• c5) repetition of steps c2) to c4) for different Tubes of the tube bundle reactor or heat exchanger up to the Tubes together with the respectively predetermined catalyst settlements are coated,
• c6) heating the coated tube bundle reactor or heat exchangers, if appropriate in the presence of inert or reak active gases to a temperature in the range of 20 to 1500 ° C for drying and optionally sintering or calcining the Catalysts.

The method d) comprises the following steps:

• d1) Preparation of solutions, emulsions and / or dispersions of elements and / or element connections in the cataly sator and / or catalyst precursor chemical present Elements and optionally dispersions of inorganic Carrier materials,
• d2) Mixing predetermined amounts of the solutions, emulsions and / or dispersions and optionally precipitation aids average in one or more parallel reactions vessels,
• d3) if appropriate, adding adhesion promoters, binders, Viscosity regulators, pH regulators and / or solid organic carriers in the mixture (s) obtained,
• d4) coating of one or more predetermined Channels of the body present catalyst supports with the Mixture or one or more of the mixtures,
• d5) repeating steps d2) to d4) for others (i.e. in usually the not yet coated) catalyst support in the channels of the body until the (preferably all) in the Channels of the body present catalyst carrier with the each predetermined (usually differ from each other ) catalyst and / or catalyst precursor compositions are coated,
• d6) optionally heating the body with the coated Catalyst supports in the channels, if appropriate in the presence of inert or reactive gases, to a temperature in the range  from 20 to 1500 ° C for drying and optionally sintering or calcining the catalysts and / or catalyst runner.

The ductility of the ducts (e.g. the inner surface of the pipes) the body or the catalyst carrier before coating by chemi mechanical, physical or mechanical pretreatment of the inner walls of the Channels (e.g. inner tubes) or the catalyst carrier or by application an adhesive layer can be enlarged. This applies in particular to the Ver drive a) and c) or b) and d).

The method e comprises the following steps:

• e1) Manufacture of different heterogeneous catalysts and / or their predecessors in the form of full contacts with right composition,
• e2) loading one or more predetermined channels of the body that prevent the heterogeneous catalyst from falling out are secured, each with one or more of the Heterogeneous catalysts and / or their precursors with vorbe right composition.
• e3) optionally heating the body with the heterogeneous catalysts sensors and / or their precursors in the channels if in the presence of inert or reactive gases, to a Temperature in the range of 20 to 1500 ° C for drying and optionally sintering or calcining the catalysts and / or catalyst precursors.

The procedure f) comprises the following steps:

• f1) coating and optionally heating predetermined ones Catalyst supports for the production of predetermined support ka talysators in the above in process b) and d) th kind outside the body,
• f2) introduction of the supported catalysts into predetermined channels of the Body,
• f3) optionally heating the filled body, if appropriate in the presence of inert or reactive gases, to a tempera tur in the range of 20 to 1500 ° C to dry and give if necessary, sintering or calcining the catalysts.

The outer shape of the supported catalysts preferably corresponds to Shape of the channel interior in the body at least essentially, preferably approximate or complete.

The invention also relates to inorganic heterogeneous catalyst arrays are obtainable by one of the above processes. The arrays can also by any combination of the above methods be put.

The processes are suitable for the production of a large number of catalysts such as described in G. Ertl, H. Knözinger, J. Weitkamp, Editor, "Handbook of Heterogeneous Catalysis", Wiley-VCH, Wein Heim, 1997 are described.  

The invention also relates to a method g) for determining catalytic properties, in particular the activity, selectivity and / or long-term stability of the catalysts described above and below in an array described, comprising the following steps:

• g1) optionally activating the catalysts in the body,
• g2) tempering the body to a desired implementation temperature,
• g3) directing a fluid reactant or a fluid reaction mixed by (one, several or all of the) channels of the Body,
• g4) (preferably separate) discharge of the converted fluids individual or several combined channels of the body pers,
• g5) (preferably separate) analysis of the implemented law fluids,
• g6) if necessary comparative evaluation of the analysis results several analyzes.

A preferred process variant is characterized in that after tempering the body to a first reaction temperature in step g2) steps g3) to g6 in succession for several different fluids Reactants or fluid reaction mixtures are carried out, in each case a purge step with a purge gas can be inserted, and then the body can be tempered to a second reaction temperature  and the above reactions are repeated at this temperature can.

It can start the analysis of the collected gas flow from the whole Arrays are analyzed to demonstrate implementation at all. Afterwards, if there is an implementation, the contributions of the individual Pipes or multiple pipes can be analyzed to a minimum Number of analysis processes to determine an optimal catalyst.

Individual pipes or several or all pipes can be combined be flowed through.

It is preferably the fluid reactant or fluid Reaction mixture around a gas or gas mixture.

The invention allows automated production and catalytic testing for the purpose of mass screening of heterogeneous catalysts for chemi cal reactions, especially for reactions in the gas phase, very particularly for partial oxidation of hydrocarbons in the gas phase molecular oxygen (gas phase oxidations).

Reactions or implementations suitable for investigation are described in G. Ertl, H. Knözinger, J. Weitkamp, editor, "Handbook of Heterogeneous Catalysis ", Wiley-VCH, Weinheim, 1997. Examples of suitable Reactions are mainly in this literature in volumes 4 and 5 listed under numbers 1, 2, 3 and 4.

Examples of suitable reactions are the decomposition of nitrogen oxides Ammonia synthesis, ammonia oxidation, sulfur water oxidation substance to sulfur, oxidation of sulfur dioxide, direct synthesis of methyl  chlorosilanes, oil refining, oxidative coupling of methane, methanol syn thesis, hydrogenation of carbon monoxide and carbon dioxide, conversion of Methanol in hydrocarbons, catalytic reforming, catalytic Cracking and hydrocracking, coal gasification and liquefaction, fuel cells, heterogeneous photocatalysis, synthesis of MTBE and TAME, isomeri sations, alkylations, aromatizations, dehydrogenations, hydrogenations, Hydroformylations, selective or partial oxidations, aminations, Halogenation, nucleophilic aromatic substitution, addition and Elimination reactions, oligomerizations and metathesis, polymerizations, enantioselective catalysis and biocatalytic reactions.

The invention is described below on the basis of preferred embodiments explained in more detail.

Manufacture of the inorganic heterogeneous catalyst arrays

First, two or more, preferably 10 or, are produced more, very particularly preferably 100 or more, in particular 1000 and more, especially 10,000 or more liquid starting mixtures (hereinafter referred to as mixtures), the selected chemical elements of the Peri included in the form of solutions, emulsions and / or before adds suspensions (dispersions), whereby the mixtures produced generally in their chemical composition or concentration differentiate. Several can be used to check the reproducibility Mixtures of the same composition are used.

The liquid mixtures generally contain a liquid chemical Component used as a solvent, emulsifying aid or dispersing aid is used for the other components of the mixture. As  Solvents or dispersing aids are organic solvents, Emulsifying agents and / or water, preferably water, are used.

Except the chemical elements of the solvent or dispersing aid the liquid mixtures contain one or more, preferably 2 or more, particularly preferably 3 or more chemical elements, where i.a. but with no more than 50 different chemical elements an amount of more than 1 wt .-% are included. Prefers the chemical elements in the mixtures are very intimate mix before, e.g. B. in the form of a mixture of different miscible Solutions, intimate emulsions with small droplet size and / or before moves as a suspension (dispersion) containing the relevant chemical elements generally in the form of a fine precipitation, e.g. B. in the form of a contains chemical mixed precipitation. This has also proven particularly successful Use of sols and gels, especially those that relevant chemical elements in a largely homogeneous distribution contain and preferably of those that one for the subsequent coating show favorable adhesion and flow behavior. As starting connections in principle, the elements come for the selected chemical elements itself, preferably in finely divided form, in addition all connections gene in question, which the selected chemical elements in appropriate Containing such as oxides, hydroxides, oxide hydroxides, inorganic salts, preferably nitrates, carbonates, acetates and oxalates, organometallic ver bonds, alkoxides, etc. The respective starting compounds can be in solid form, in the form of solutions, emulsions and / or in the form of Suspensions are used.

Preferred element compounds, especially catalytically active metals, are water-soluble oxides, hydroxides or salts with organic or inorganic acids. Active metals are preferably found in the secondary  groups of the periodic table of the elements, for example in the 5th and 6th Sub group for oxidation catalysts and in the platinum group for hydrie tion catalysts. The method according to the invention also allows the scree ning of (atypical) elements not previously considered to be catalytically active ten, especially metals or metal oxides.

In addition, the liquid mixture can contain further compounds which influence the adhesive properties and the flow behavior of the liquid mixture on the inside of the channel or the inside of the pipe or catalyst support and thus the coating properties of the liquid mixture. Here are z. B. ethylene glycol or glycerin, as described in DE-A 44 42 346, or z. B. maleic acid copolymers and as inorganic compounds such. B. SiO ₂ , Si organic compounds or siloxanes.

Furthermore, the mixtures can contain known inorganic carrier materials such as Al ₂ O ₃ , ZrO ₂ , SiO ₂ , Y ₂ O ₃ , TiO ₂ , activated carbon, MgO, SiC or Si ₃ N ₄ , which generally have the surface of the mixture accessible to catalysis Increase contained catalytically active chemical elements, which can also affect the catalytic properties of the Aktivmas sen obtained and which can also affect the adhesive and flow properties of the mixture obtained. As a rule, coatings are obtained which contain the preferably oxidic, nitridic or carbide carrier material in addition to the actual catalytic material. When the components are mixed or when the coating is subsequently heated, the carrier material mentioned can also contain the chemical elements used above react to a new solid material.

Furthermore, the mixtures used can additionally contain an inorganic one and / or contain organic binder or a binder system which the used mixture stabilized. For this, z. B. Binder or Binder systems, the metal salts, metal oxides, metal oxide hydroxides, metal oxide hydroxide phosphates and / or at the operating temperature of the catalyst contain melting eutectic compounds.

The mixture can also be added by adding acids and / or bases a defined pH range. In many cases pH-neutral suspensions are used. The mixture can be more advantageous indicate a pH between 5 and 9, preferably between 6 and 8, can be set. Special results are with the invention Achieve process when the mixture has a high solids content up to 95 wt .-%, preferably 50 to 80 wt .-% at low viscosity having. If the precipitation is insufficient, precipitation aids such as ammonia can be used be added.

In a preferred embodiment of the invention, the mixture gradually and in general also during production and their Flowability continuously, but measured at least at the end of production sen. This can e.g. B. by measuring the current consumption of the stirrer respectively. With the help of this measurement, the viscosity of the suspension z. B. adjusted by adding further solvents or thickeners be that optimal adhesion, layer thickness and layer thickness even Liquid on the inner pipe wall to be coated or to be coated the auxiliary support (catalyst support) results.

Basically, the invention is not limited to certain catalyst materials and limited catalyst compositions. The preparation of the mixture can be done in parallel or in succession and is usually done in auto  matised form, e.g. B. with the help of an automatic pipetting or pipetting robotors or an ink-jet process, as described, for example, in US 5,449,754.

For coating the tubes of the tube bundle reactor or heat exchanger According to process variant a), solutions, emulsions or suspensions individual elements or element connections separated from each other at the same time be introduced into the pipes continuously or in succession. The same time For example, a modified ink jet can be used (Inkjet printer printhead), the separate feed lines for the contains individual solutions, emulsions or suspensions and at the same time Allowing spraying allowed. Compared to this process variant a, the Ver preferred variant b, which is carried out in particular as follows:

To produce the catalysts or their precursors, first of all Solutions, emulsions and / or suspensions of the required elements in separate vessels. These are often metal salt solutions solutions, for example nitrates. Of the separate solutions, those for the preparation of a catalyst or catalyst precursor Quantities in the desired ratio in a small separate Reaction container transferred in which an intensive mixing of the com components. The dosage can be done, for example, with the aid of pipetting machines or inkjet. When mixing the components can there is a reaction or precipitation of the components. With the help of Precipitating agents such as ammonia may be precipitated or completed so that often a suspension of the mixed catalyst precursor material is available.

Since the suspension should have a suitable viscosity to be in a Pipe of the tube bundle reactor can be introduced and distributed, so  that there is an even and largely adhesive distribution of the catalyst or catalyst precursor on the inner tube wall, If necessary, the appropriate viscosity of the suspension can be as above described with other additives aimed at the desired value can be set. The suspension is removed from the reaction container can, for example, with pipettes, the distribution in the pipe, such as described standing up, by spraying or spraying. Of the The reaction vessel can be completely or partially emptied. It can several reaction vessels are operated in parallel, or one reaction Container can be filled with other components after partial emptying in order to arrive at a changed composition.

Coating with the mixtures produced is preferably carried out by means of a spraying process, on different parts of a metallic one Pipe reactor or heat exchanger, especially on the inner walls of the pipe of (preferably metallic) reaction tubes of a tube bundle reactor a 10 to 2000 µm thick layer, with each tube in general a mixture of different compositions is coated (for Reproducibility can also be checked using several mixtures the same composition can be used in several pipes).

To check layer thickness effects (such as transport effects) also the same catalyst compositions with different ones Layer thicknesses can be applied in different pipes.

In a further variant of the invention, auxiliary carriers (are preferred metallic or ceramic tubes) used after or preferably before the insertion into the reaction tubes of a tube bundle reactor with the liquid gene mixture have been coated.  

For the parts coated with the previously prepared liquid mixture the, preferably metallic, heat exchanger is preferably around the inner tube walls of, preferably, metallic tube bundle reactors. The reaction tubes of the tube bundle reactor can have any cross have cut, but usually have a round and in particular circular cross section. The inside diameter is preferably 0.2 to 70 mm, preferably 1 to 25 mm, particularly preferably 3 to 10 mm. The tube bundle reactor can have up to 30,000 reaction tubes or more, preferably 10 to 20,000, particularly preferably 100 to 10,000 reaction contain pipes, each with a different composition Coating.

The coating with liquid mixtures can be done by sponging, Slip, brush, spin, spray and / or dip applied become. Furthermore, the mixture can be poured into the individual tubes and at speeds between 200 and 1000 rpm, preferably at speed numbers between 300 and 800 rpm, to be thrown. In a before preferred embodiment, the coatings on the inside of the Reaction tubes by spraying the above liquid mixture manufactured. The sprayed mixture material presses into the Roughness of the subsurface, with air bubbles under the Coating can be prevented. The mixture used can adhere completely to the sprayed inside. But it can also, ins especially with lower adhesion and / or low viscosity of the mixture part of the mixture can be discharged again by dripping down. The auxiliary carrier to be coated, e.g. B. in the form of inner tubes can be full be coated continuously or only partially. In particular, the respective reactor tube inlet and reactor tube outlet by a ge suitable device from the coating to be left out later occurring sealing problems with the supply and  Prevent drainage devices for the fluid. Has also proven itself a coating in which the mixture is poured into the preheated tube is sprayed or this mixture by immersion in the preheated pipe is introduced. To do this, the metallic base body is opened spray the suspension to 60 to 500 ° C, preferably 200 to 400 ° C and more preferably 200 to 300 ° C preheated and at this temperature coated with the mixture described above. In doing so, a Much of the volatile components of the mixture evaporate and one preferably 10 to 2000 microns, particularly preferably 20 to 500 microns thick Layer of the catalytically active metal oxides on the preferably metallic Basic body formed. This type of manufacture can e.g. B. as in DE-A-25 10 994 described take place with the variant that the mixture does not a preheated support, but on a preheated preferably metallic base body is applied.

To achieve particularly thick layers or particularly homogeneous loading The reaction tubes can also be coated several times be carried out in succession. You can choose between the individual Coatings of a reaction tube separate drying and / or calci kidney and / or sintering steps are interposed. The inner wall In the case of spraying, layering is advantageous with the help of an or several spray lances, preferably with one or more movable Spray lances carried out. The spray lance is used during spraying gangs z. B. with the help of an automatic device with a defined constant or varying speed due to the coating Tube pulled.

The thickness of the applied layer after drying and if necessary Calcination or sintering is preferably 10 to 2000 microns, especially preferably 20 to 500 microns.  

In addition, an adhesive can first be applied to the inner tube before coating middle and then a catalyst material on this coupling agent containing and catalytically active top layer are applied. By the adhesion promoter can adhere to the catalytically active top layer be increased on the inner tube. In addition, when using a Adhesion promoter's service life will be extended. Suitable adhesion promoters are described above.

In addition, the adhesion of the catalytic layer through a chemical, physical or mechanical pretreatment of the inner tube be increased before coating. With chemical pretreatment can the inner tubes z. B. pickled with alkali or preferably with acids become. Furthermore, e.g. B. the inner tube by blasting with a dry blasting medium, in particular corundum or quartz sand roughened to support liability. Beyond that too Detergent proven that a suspension of hard particles, for. B. Corundum, in a dispersion liquid.

In addition, the coating on the preferably metallic Inner tube containing the components auxiliary carrier and a catalyst material and catalytically active cover layer, as described for example in DE-A-196 00 685 is described. The subcarrier shows draws up an external shape, that of the geometry of the surface to be coated area corresponds at least essentially. Come as an auxiliary carrier For example, metallic or ceramic body in question, for. B. Braids made of wire or pipes made of metal or ceramic. At least that is Subcarrier and preferably only the subcarrier with the catalytically active Coated top layer and the coated subcarrier throughout the reak tion inner tube or preferably in a part of the inner reaction tube orderly. With this tube-in-tube arrangement, the outer tube can, for example  have a taper at one end to prevent the To prevent the inner tube, at the other end, the protruding Inner tubes, for example by springs or a resilient material in the Outer tube are pressed.

The special thing about the method according to the invention is that each auxiliary another carrier in the tube bundle reactor used in general Composition or another layer thickness of the catalytic Has coating. In addition, the coated subcarrier easily exchanged for other subcarriers with different coatings become. For example, a suitable reactor design (Vor see shut-off valves etc.) a change of individual subcarriers during operation of the reactor.

When heating the coated tube bundle reactor under vacuum or under a defined gas atmosphere at temperatures from 20 to 1500 ° C, preferably 60 to 1000 ° C, particularly preferably 200 to 600 ° C, very particularly the previously applied coating is more preferably 250 to 500.degree freed from the preferably aqueous solvent by drying. With increased Temperature can also be a sintering or calcination of the Coating particles take place. In this process, in the Usually get the actual catalytically active coating.

For temperature control, the reaction tubes are preferably of one Heat transfer medium, for example from a molten salt or liquid surrounded by metal like Ga or Na. The liquid heat transfer germ medium preferred at opposite points of the tube well delreactor fed and discharged, for. B. by means of a pump, then it for heat absorption or heat absorption via a (e.g. air-cooled) To drive heat exchangers. On the one hand, the heat transfer medium ensures  that the temperature for drying, for any subsequent Sintering of the coating and for the subsequent fluid phase test reaction is set in the reaction tubes. On the other hand, the Heat transfer medium that occurs during the subsequent test reaction Dissipated amount of heat and thus along the catalyst coating Formation of so-called hot spots (hot spots) in which locally a higher Temperature prevails than in the rest of the catalyst coating, suppressed.

This type of reaction ensures that the reaction occurring heat is dissipated excellently, so that practically no hot Spot occurs more.

In a further embodiment of the invention, the between the Reaction tube space with a solid material, preferably filled with a metal or with a solid metal alloy. In this case the tube bundle reactor goes into a material as described above block, especially metal block with channels or holes. Here the inside diameter of the holes corresponds to the inside diameter of the Reaction tubes of the tube bundle reactor.

It is also possible to use different heterogeneous catalysts in the form of Full contacts or supported catalysts according to known, for example com binatory process to produce with a predetermined composition and each one or more predetermined tubes of the tube bundle reactor or heat exchanger with any of these prefabricated heterogeneous catalysts to load. The known types of moldings can ver be applied. For each individual pipe it is possible to choose the dumping height or to vary the inert content of a filling or other filling parameters adjust.  

The catalysts are tested by reacting fluid reactants or reaction mixtures which are generally in liquid or preferably gaseous form. Oxidation catalysts are preferably tested by subjecting individual, several or all tubes of the coated tube-bundle reactor to a gas mixture of one or more saturated, unsaturated or polyunsaturated organic starting materials (e.g. hydrocarbons, alcohols, aldehydes etc.) in parallel or in succession. ), Oxygen-containing gas (e.g. air, O ₂ , N ₂ O, NO, NO ₂ , O ₃ ) and / or z. B. H ₂ , and optionally an inert gas, e.g. B. nitrogen or a noble gas, at temperatures of 20 to 1200 ° C, preferably at 50 to 800 ° C, particularly preferably at 80 to 600 ° C, with the appropriate parallel or successive de separate discharge of the respective gas streams of the single, several or all reaction tubes of the tube bundle reactor is ensured.

Due to the generally differently coated reaction tubes of the tube bundle reactor, a gas mixture of z. B. an oxygen-containing gas (z. B. air, O ₂ , N ₂ O, NO, NO ₂ , O ₃ ) and / or H ₂ and the organic starting material to be reacted (for example propene or o-xylene) passed. In addition to the gaseous substances mentioned, other gaseous substances, such as Cl or P-containing substances, can also be present. The gas mixture can be passed through the individual reactor tubes one after the other. In the preferred embodiment, the gas mixture is passed through the reaction tubes in such a way that the gas mixture flows through all tubes simultaneously. It can be changed during startup of the reaction, ie during the activation time of the catalytic coatings, the composition of the feed, the temperature of the heat exchange medium or the reaction tube, the residence time of the feed and / or the pressure of the total gas in the Rohrbün delreaktor. The product gases leaving the respective reaction tube, which result from the reaction of the reaction gases used, are generally derived separately, but optionally also in combination, and, for. B. analyzed in terms of their composition, using various probes or analysis methods.

The application of the coated tube bundle reactor with the above Gas mixing can also take place directly after the suspension coating (omitting drying and sintering or calcining), wherein in in this case, the drying and possibly subsequent sintering process the gas mixture mentioned takes place. The assembly can Change the coating of the inner tube. In particular, oxidic Coatings under strongly reducing conditions their oxygen partially or fully released or under strongly oxidizing conditions Include oxygen in their structure.

The supply of a constant gas mixture to the individual, differed Lich coated reaction tubes of the tube bundle reactor can, for. B. about a Gasver which can be placed in a gas-tight manner on the tube bundle reactor care hood.

The mixing of the gases used can take place in the Gas supply hood or only in this, for. B. with the help of a static Mixer.

The individual reaction gases can be discharged via a tube on the tube delreaktor essentially gas-tight device, wherein the individual reaction gases of the individual several or all reaction tubes derived separately and then analyzed separately via a valve circuit be settled.  

Another way of taking the individual exhaust gases of each generally in general deriving separately coated reaction tubes consists in one e.g. B. computer controlled mechanically moving "sniffing device" with a Sniffer line for the gas to be withdrawn, which is essentially automa table on, in or above the exit of the respective reaction tube positio is kidney and then takes a reaction gas sample. The position tion and removal of the respective reaction gas is preferred in carried out in such a way that only the actual one to be analyzed later Reaction gas and no additional foreign gas from outside into the sniffing egg tion arrives. If the positioning of the sniffer device on the The end of the reaction tube is essentially gas-tight the sniffer line on the reaction tube end, e.g. B. by pressing the Sniffing device on the front of the tube actuator, an advantage. If the positioning of the sniffer device in or above the exit of the reaction tube takes place, it is advantageous to the reaction gases via a negative pressure set in the sniffer line in the manner in the sniffers to suck that amount of the sucked reak tion gases is so limited that no additional foreign gases in the sniffer be sucked in. It has proven to be particularly advantageous in the case the positioning of the sniffer line in the exit of the respective Reaction tube proved if the end of the sniffer line in the way is tapered that by inserting the sniffer line in the end of the each reaction tube a substantially gas-tight seal from the relevant reaction tube emerging reaction gases against the Outside space is guaranteed. After the reaction gas has been withdrawn The sniffer is the considered reaction tube of the tube bundle reactor device - preferably automatically - on, in or over another, usually the closest exit of another reaction tube positioned to accomplish the next gas extraction there. To this Way, all exhaust gases from the reaction tubes can be used for sampling  approached separately and then analyzed. It is not just possible to position on, in or over the reaction tube exit is moved and the tube bundle reactor is fixed, but the sniffing egg device can be fixed during the positioning and the tube bundle reactor be moved accordingly. During positioning, too both the sniffer device and the tube bundle reactor are a Bewe experience. In a preferred process variant, the tube well remains delreaktor unchanged and only the sniffer is during the Positioning moved over or on the respective reaction tube ends. In The tube bundle reactor experiences another preferred process variant during the positioning a rotational movement around its axis, while the sniffer line when positioning over the respective reaction a linear movement in the direction of the axis of rotation of the tube bundle reacts while positioning on each Reaction tube ends the sniffer device an additional movement carried out parallel to the reactor axis. There can also be several sniffers directions simultaneously for sampling the different reaction gases be used. In addition, several samples can be sampled together pipes made.

In an analogous manner, such as gas discharge via so-called sniffer lines the gas supply line can also be used as an alternative to the gas supply hood using such a principle, with sequential testing of the individual pipes. Of course, the exhaust sniffer line must be used be positioned synchronously with the fresh gas supply line.

Screening the catalytic performance of each catalytic Coatings of individual reaction tubes can be done by chemical analysis of the respective gas streams using suitable methods known per se respectively. The from the individual reaction tubes of the tube bundle reactor  individually derived gas streams are z. B. by means of a suitable pre directions z. B. via gas chromatography with FID and / or WLD as Detector, or e.g. B. individually by mass spectrometry on their together setting analyzed. The gas composition obtained is in particular re regarding their relative content of the desired product wisely analyzed on various desired products and the ones obtained Concentrations in relation to the reacted reactant, whereby Values for the respective sales (activity) and product selectivities surrender. In many cases it is useful to use the product selectivities of the individual catalysts over a longer period of time in general Measure hours to several weeks. When selecting the for the each reaction most suitable catalyst coating it can to the number to limit the gas analysis, be useful to repeat measurements only on gas compositions from selected reactor tubes determine the desired limit concentration or limit selectivity certain products.

After the catalytic test, the applied catalytic interior layers are removed, so that the tube bundle reactor obtained again a renewed catalytic coating is accessible.

The catalyst coatings can be replaced by replacing the old one catalytically active top layer of the coating at least essentially is removed and a new catalytically active coating Sponging, brushing, spinning, spraying and / or dipping becomes. The same coating method should expediently be chosen, with which the previously removed catalytic coating was applied is. The removal of the old, catalytically active top layer of the coating device can in particular by blasting with a blasting medium, for. B. Ko round, silicon carbide, fine sand or the like, in a simple manner  happen. Alternatively, treatment with steam or proven the use of chemical ablation methods.

An efficient method of removing the inner coatings - for example wise after the catalyst test - represents the use of brush devices gene, e.g. B. analogous to a bottle brush, usually in conjunction with the described cleaning agents. Removal of the Interior coatings in an at least largely automated way.

The method according to the invention can easily be performed in an automated form Robots. A coating of pipes with the Catalyst ensures optimal fluid flow, only causes low pressure loss and prevents blockages in the individual reak tion tubes of the tube bundle reactor.

The spatial separation and clear allocation of the tested coating tings offers the advantage of having one device (tube bundle) at the same time number of materials generally corresponding to the number of pipes to be able to test in parallel with reduced costs and time.

Furthermore, in comparison to other systems, the tube bundle reactor offers e.g. B. perforated plates, CVD arrays, etc. the advantage of being as close as possible to one technical process (scale-up capability is retained). It can a technically relevant optimization very quickly and inexpensively be carried out, especially because of a variety of catalysts can be tested in parallel / simultaneously under the same conditions.

Claims (21)

1. Array composed of heterogeneous catalysts and / or their precursors from a body, preferably parallel, continuous channels and in which at least n channels n different heterogens contain catalysts and / or their precursors, where n is 2, preferably 10, particularly preferably 100, in particular 1000, especially Has 10,000. 2. Array according to claim 1, characterized in that the heterogeneous catalysts are inorganic heterogeneous catalysts. 3. Array according to claim 1 or 2, characterized in that the Body is a tube bundle reactor or heat exchanger and the channels Are pipes, or the body is a block of solid material, which has the channels. 4. Array according to one of claims 1 to 3, characterized in that the heterogeneous catalysts and / or their precursors full contacts or Supported catalysts and / or their precursors and as catalysts gate filling, tube wall coating or auxiliary carrier coating lie. 5. A method for producing arrays according to one of claims 1 to 4, comprising the following steps:

• a1) preparation of solutions, emulsions and / or dispersions of elements and / or element compounds of the elements present in the catalyst and / or catalyst precursor, and optionally of dispersions of inorganic support materials,
• a2) optionally adding adhesion promoters, binders, viscosity regulators, pH regulators and / or solid organic carriers to the solutions, emulsions and / or dispersions,
• a3) simultaneous or successive coating of the channels of the body with the solutions, emulsions and / or dispersions, a predetermined amount of the solutions, emulsions and / or dispersions being introduced into each channel in order to obtain a predetermined composition, and
• a4) optionally heating the coated body, if appropriate in the presence of inert or reactive gases, to a temperature in the range from 20 to 1500 ° C. for drying and optionally sintering or calcining the catalysts and / or catalyst precursors.

6. A method for producing arrays according to one of claims 1 to 4, comprising the following steps:

• b1) preparation of solutions, emulsions and / or dispersions of elements and / or element compounds of the elements present in the catalyst and / or catalyst precursor, and optionally of dispersions of inorganic support materials,
• b2) if appropriate, adding adhesion promoters, binders, viscosity regulators, pH regulators and / or solid organic carriers to the solutions, emulsions and / or dispersions,
• b3) simultaneous or successive coating of catalyst supports present in the channels of the body with the solutions, emulsions and / or dispersions, a predetermined amount of the solutions, emulsions and / or dispersions being introduced into each channel in order to apply a predetermined composition to the catalyst supports received, and
• b4) optionally heating the body with the coated catalyst supports in the channels, optionally in the presence of inert or reactive gases, to a temperature in the range from 20 to 1500 ° C. for drying and optionally sintering or calcining the catalysts and / or catalyst precursors.

7. A method for producing arrays according to one of claims 1 to 4, comprising the following steps:

• c1) preparing solutions, emulsions and / or dispersions of elements and / or element compounds of the chemical elements present in the catalyst and / or catalyst precursor and optionally of dispersions of inorganic support materials,
• c2) mixing predetermined amounts of the solutions, emulsions and / or dispersions and, if appropriate, precipitation aids in one or more reaction vessels operated in parallel,
• c3) if appropriate, adding adhesion promoters, binders, viscosity regulators, pH regulators and / or solid organic carriers to the mixture (s) obtained,
• c4) coating one or more predetermined channels of the body with the mixture or several mixtures,
• c5) repeating steps c2) to c4) for other channels of the body until the channels are coated with the respectively predetermined catalyst and / or catalyst precursor compositions,
• c6) optionally heating the coated body, if appropriate in the presence of inert or reactive gases, to a temperature in the range from 20 to 1500 ° C. for drying and optionally sintering or calcining the catalysts and / or catalyst precursors.

8. A method for producing arrays according to one of claims 1 to 4, comprising the following steps:

• d1) preparing solutions, emulsions and / or dispersions of elements and / or element compounds of the chemical elements present in the catalyst and / or catalyst precursor and, if appropriate, of dispersions of inorganic support materials,
• d2) mixing predetermined amounts of the solutions, emulsions and / or dispersions and, if appropriate, of precipitation aids in one or more reaction vessels operated in parallel,
• d3) optionally adding adhesion promoters, binders, viscosity regulators, pH regulators and / or solid organic carriers to the mixture (s) obtained,
• d4) coating catalyst supports present in one or more predetermined channels of the body with the mixture or one or more of the mixtures,
• d5) repeating steps d2) to d4) for other channels of the body until the catalyst supports present in the channels of the body are coated with the respectively predetermined catalyst and / or catalyst precursor compositions,
• d6) optionally heating the body with the coated catalyst supports in the channels, optionally in the presence of inert or reactive gases, to a temperature in the range from 20 to 1500 ° C. for drying and optionally sintering or calcining the catalysts and / or catalyst precursors.

9. The method according to claim 5 or 7, characterized in that the Adhesion of the channels of the body before coating chemical, physical or mechanical pre-treatment of the interior walls of the channels or enlarged by applying an adhesive layer becomes. 10. A method for producing arrays according to one of claims 1 to 4, comprising the following steps:

• e1) manufacture of different heterogeneous catalysts and / or their precursors in the form of full contacts with a predetermined composition,
• e2) charging one or more predetermined channels of the body, which are secured against the heterogeneous catalysts from falling out, with one or more of the heterogeneous catalysts and / or their precursors with a predetermined composition,
• e3) optionally heating the body with the heterogeneous catalysts and / or their precursors in the channels, if appropriate in the presence of inert or reactive gases, to a temperature in the range from 20 to 1500 ° C. for drying and optionally sintering or calcining the catalysts and / or catalyst precursor.

11. A method for producing arrays according to one of claims 1 to 4, comprising the following steps:

• f1) coating and, if necessary, heating predetermined catalyst carriers for producing predetermined carrier catalysts in the manner defined in claim 6 or 8 outside the body,
• f2) introduction of the supported catalysts into predetermined channels in the body,
• f3) optionally heating the filled body, optionally in the presence of inert or reactive gases, to a temperature in the range from 20 to 1500 ° C. for drying and optionally sintering or calcining the catalysts.

12. The method according to claim 11, characterized in that the outer shape of the supported catalysts the shape of the channel interior in the body corresponds at least essentially. 13. Array obtainable by a process according to one of claims 5 until 12. 14. A method for determining the activity, selectivity and / or long-term stability of the catalysts in an array according to one of claims 1 to 4 or 13, comprising the following steps:

• g1) optionally activating the catalysts in the body,
• g2) tempering the body to a desired reaction temperature,
• g3) passing a fluid reactant or a fluid reaction mixture through channels in the body,
• g4) discharge of the converted fluids from individual or several combined channels of the body,
• g5) analysis of the discharged converted fluids,
• g6) if necessary, comparative evaluation of the analysis results of several analyzes.

15. The method according to claim 14, characterized in that according to the Tempering the body to a first transition temperature in step g2) steps g3) to g6) in succession for several different ones fluid reactants or fluid reaction mixtures are carried out, where a purging step with a purging gas can be inserted, and then the body to a second reaction temperature can be tempered and the above reactions in this Temperature can be repeated. 16. The method according to claim 14 or 15, characterized in that it the fluid reactant or fluid reaction mixture Gas or gas mixture. 17. The method according to any one of claims 14 to 16, characterized in net that it is a gas phase oxidation in the implementation delt. 18. The method according to claim 17, characterized in that a molecule laren oxygen-containing reaction mixture is used.   19. The method according to claim 6 or 8, characterized in that the Adhesion of the catalyst carrier in the body before coating by chemical, physical or mechanical pretreatment of the Catalyst carrier or enlarged by applying an adhesive layer becomes. 20. The method according to any one of claims 5 to 12 and 14 to 19, characterized characterized in that the process is automated.