DE19624485A1 - New supported catalyst based on ruthenium or palladium - Google Patents

Abstract

A new catalyst (I) contains 0.01-30 wt% ruthenium or palladium as active metal, optionally together with Group I, VII or VIII transition metal(s), on a carrier (II) in which (novel feature) 10-50% of the pore volume consists of macropores with a pore diameter (PD) of 50-10,000 nm and 50-90% consists of mesopores with a PD of 2-50 nm. Also claimed are (i) a process for conversion of polymers containing multiple C-C bond(s) in presence of (I) and (ii) a process for conversion of organic compounds in the presence of (I) in which the active metal is ruthenium.

Description

The present invention relates to a process for the hydrogenation of a aromatic compound in which at least one hydroxyl group is attached to one aromatic nucleus is bound, or an aromatic compound in which at least one amino group is bonded to an aromatic nucleus, in Presence of a catalyst, the active metal / e ruthenium and opp optionally one or more other metals from I., VII. or VIII. Subgroup of the periodic table contains, applied to a porous Carrier.

In one embodiment, the present invention relates to a process for the hydrogenation of an aromatic compound in which at least one hydroxyl group is bonded to an aromatic nucleus, preference being given to, in addition to the at least one hydroxyl group, at least one, optionally substituted, C _1-10 -alkyl group and / or at least one C _1-10 alkoxy group is attached to an aromatic nucleus. Furthermore, monoalkyl-substituted phenols are preferably used in the process according to the invention.

The mono- or polynuclear aromatic compounds are in Presence of the catalyst described herein to the corresponding  Cycloaliphatic compounds hydrogenated, the hydroxyl group being obtained remains.

Cycloaliphatic alcohols, especially alkylcyclohexanols, are important Intermediate products for the manufacture of various fragrances, pharmaceuticals and other fine organic chemicals. By catalytic hydrogenation of the corresponding aromatic precursors are the above cycloaliphatic Alcohols easily accessible.

The process of alkylcyclohexanols by catalytic hydrogenation of the ent It is known to produce speaking alkylphenols. The hydrogenation of Alkylphenols to the corresponding alkylcyclohexanols in the presence of Hydrogenation catalysts, in particular supported catalysts ren has been described many times.

Metallic rhodium, Rhodi, for example, are used as catalysts um-platinum, rhodium-ruthenium alloys as well as ruthenium, palladium or Nickel used on catalyst supports. As a catalyst support Carbon, barium carbonate and especially aluminum oxide are used.

In PL 137 526 the hydrogenation of p-tert-butylphenol is too p-tert-Butylcyclohexanol described using a nickel catalyst.

DE-A-34 01 343 and EP 0 141 054 describe a method for Production of 2- and 4-tert-butylcyclohexanol from 2- and 4-tert-butylphe described by catalytic hydrogenation. The hydrogenation is two-stage fig executed, with a palladium catalyst in the first stage an Al₂O₃ carrier and a ruthenium catalyst in the second stage an Al₂O₃ carrier is used. The metal content on the carrier is 0.1 to 5% by weight. The carriers are not further specified.  

It works at a pressure of 300 bar with product return, and the cis-tert-butylphenols are preferably obtained, 0.1 up to 0.5% by-products.

US 2 927 127 describes a process for the preparation of p-tert-Bu tylcyclohexanol and esters thereof by catalytic hydrogenation of p-tert-butylphenol. 5% rhodium on carbon are used as catalysts, 5% palladium on barium carbonate and 5% ruthenium on carbon used. When using ruthenium on carbon, it was used a pressure of 70 to 120 bar and a temperature of 74 to 93 ° C worked. 66% cis isomer was obtained as the hydrogenation product.

DE-A-29 09 663 describes a process for the preparation of cis-alkylcy clohexanols by catalytic hydrogenation of the corresponding alkylphenols described. As a catalyst was ruthenium on an Al₂O₃ support used. It was operated at pressures of 40, 60 or 80 bar. As The product was predominantly cis-alkylcyclohexanols, where as By-product 0.1 to 1% alkylbenzenes were obtained.

In a further embodiment, the present invention relates to a process for the hydrogenation of an aromatic compound in which at least one amino group is bonded to an aromatic nucleus, preference being given to, in addition to the at least one amino group, at least one, optionally substituted, C _1-10 -alkyl group and / or at least one C _1-10 alkoxy group is attached to an aromatic nucleus. Monoallyl-substituted amines are particularly preferably used.

The mono- or polynuclear aromatic compounds are in Presence of the catalyst described herein to the corresponding  Cycloaliphatic compounds hydrogenated, the amino group being obtained remains.

Cycloaliphatic amines, especially optionally substituted cyclo hexylamine and dicyclohexylamine, are used for the production of Anti-aging agents for rubbers and plastics, as corrosion protection as well as intermediate products for crop protection agents and textile auxiliaries. Cycloaliphatic diamines are also used in the production of polyamide and Polyurethane resins used and continue to be used as Hardener for epoxy resins.

It is known to cycloaliphatic amines by catalytic hydrogenation of the to produce corresponding mono- or polynuclear aromatic amines. The Hydrogenation of aromatic amines to the corresponding cycloaliphati cal amines in the presence of hydrogenation catalysts, in particular Supported catalysts have been described many times.

Raney cobalt with basic additives, for example, are used as catalysts (JP 43/3180), nickel catalysts (US 4 914 239, DE 8 05 518), Rhodi um catalysts (BE 73 93 76, JP 70 19 901, JP 72 35 424), and Palladium catalysts (US 3 520 928, EP 501 265, EP 53 818, JP 59/196 843) used. The majority, however, contain ruthenium-containing catalysts gates used.

DE 21 32 547 describes one or more hydrogenation processes robust aromatic diamines to the corresponding cycloaliphatic Amines known in the presence of a suspended ruthenium catalyst is performed.  

EP 67 058 describes a process for the preparation of cyclohexylamine by catalytic hydrogenation of the corresponding aromatic amine described. As a catalyst, ruthenium metal is finely divided Form used on activated aluminum pellets. After four returns the catalyst began to lose its effectiveness.

EP 324 984 relates to a method for producing a mixture from optionally substituted cyclohexylamine and optionally substituted tem dicyclohexylamine by hydrogenation of optionally substituted Aniline using a ruthenium and palladium on a support containing catalyst, which also has an alkaline reaction Contains alkali metal compound as a modifier. A similar one in principle The process is described in EP 501 265, where the catalyst contains niobic acid, tantalic acid or a mixture of both as modifiers.

US Pat. No. 2,606,925 describes a process for producing an aminocyclo hexyl compound by hydrogenating an appropriate aromatic ver Binding described, wherein a ruthenium catalyst, the active catalyti cal component is selected from elemental ruthenium, ruthenium oxides, ruthenium salts, in which the ruthenium is in the anion or in the cation is available. As the examples of this procedure show, there too the catalyst is prepared in a separate step and dried and after longer drying time introduced into the reaction vessel.

Another process for the preparation of cyclohexylamine is in the US 2,822,392, the main focus of this patent being the use of a special reactor in which the aniline and the Hydrogen as starting products in countercurrent with each other for reaction brought, is directed.  

US 3,636,108 and US 3,697,449 relate to catalytic hydrogenation aromatic nitrogen containing compound using a Ruthenium catalyst, which also has an alkali metal compound as a modifi decorative means.

Common to all of the methods described above is the use of Mesoporous supports with BET surfaces typically between 50 and are over 1000 m² / g in order to have a high activity of the catalyst achieve.

It has also been found to be particularly useful in the hydrogenation with a rhodium content gene catalyst, in addition to the high price for the catalyst, as a disadvantage proved that it is not uncommon for larger amounts of these reactions Alkylbenzenes as well as other, unidentifiable compounds, which the hydrogenation are formed as decomposition or by-products, occurred. These by-products make processing and cleaning more difficult of the reaction product especially when e.g. B. Alkylcyclohexanols as Fragrances or to be used for the production of fragrances. Furthermore, the activity of many of the methods described above decreases used catalysts quickly, especially when the Hydrogenation to accelerate the reaction rate at higher Reaction temperatures is carried out.

A catalyst consisting of a macroporous support material on which a metal of subgroup VIII of the periodic table is applied, the used for the hydrogenation of carbon-carbon double bonds can be described in US 5 110 779. Ninety percent of the Carrier existing pores of the catalyst described there have a diameter of more than 100 nm. The ratio of Surfaces from metal to carrier are 0.07 to 0.75: 1  in the context of this patent specification in particular on the large surface of the Metal in relation to the carrier, and stated as surprising ben because such a catalyst still has a high activity.

An object of the present invention was accordingly to provide development of a process for the hydrogenation of an aromatic compound, such as initially defined, with very high yields or almost full constant sales can be achieved.

Another object of the invention is to provide one of the like process, with only a minimal proportion of by-products or decomposition products during the hydrogenation.

It should also be possible to run the process under high catalyst loading long service life with an extremely high turn-over number supply, the corresponding hydrogenation products in high yield and high purity can be obtained.

One or more of the above tasks are solved by a Process for the hydrogenation of an aromatic compound, in which mind at least one hydroxyl group is attached to an aromatic nucleus, or a compound in which at least one amino group is attached to one aromatic nucleus is bound in the presence of a catalyst which as the active metal ruthenium alone or together with at least one Metal of the I., VII. Or VIII. Subgroup of the periodic table in an amount of 0.01 to 30 wt .-%, based on the total weight of the catalyst, applied to a carrier, comprises, thereby ge indicates that 10 to 50% of the pore volume of the carrier of Macropores with a pore diameter in the range from 50 nm to  10,000 nm and 50 to 90% of the pore volume of the meso carrier pores with a pore diameter in the range of 2 to 50 nm be det, the sum of the pore volumes ad 100% dated.

The above tasks as well as other tasks, if any by processes for hydrogenation, as described in the subclaims ben are solved. A particular advantage of the method according to the invention is that very good results when using only low metal contents can be achieved in the catalyst.

The term "aromatic compound in which at least one hydroxyl group pe is bound to an aromatic nucleus "or" aromatic compound tion in which at least one amino group is attached to an aromatic nucleus "is all connections that are a unit of the following Structure (I) have:

wherein R represents a hydroxyl or an amino group.

If aromatic compounds are used in the process according to the invention in which at least one hydroxyl group and furthermore at least one optionally substituted C _1-10 -alkyl radical and / or alkoxy radical are bound to an aromatic nucleus, depending on the reaction conditions (temperature, solvent ) the isomer ratio obtained from cis to trans-configured products can be varied within a wide range. Furthermore, the compounds obtained can be processed further without further purification steps. The formation of alkylbenzenes is practically completely avoided.

Like the compounds described above, in which at least one hydroxyl group is bound to an aromatic nucleus, aromatic compounds in which at least one amino group is bound to an aromatic nucleus can also be selected with high selectivity to the corresponding cycloaliphatic compounds in the process according to the invention are hydrogenated, the statements made above for the amines additionally substituted with a C _1-10 alkyl radical and / or alkoxy radical with respect to the ratio of the cis and trans isomers.

In particular, the formation of Deamination products, such as cyclohexanes or partially hydrogenated Dimerization products such as phenylcyclohexylamines, practically completely avoided.

Furthermore, the method according to the invention exhibits high turn-over numbers high catalyst load and over long catalyst life. The catalyst load is the space / time yield of the process, d. H. the amount of reactant reacted per unit of time and per amount present catalyst. Service life means the time or the amount of reacted educt that a catalyst copes with without losing its properties lose and without significantly changing the product properties.  

LINKS Aromatic compounds containing at least one hydroxyl group an aromatic core is bound

With the process according to the invention, aromatic compounds in which at least one hydroxyl group and preferably also at least one optionally substituted C _1-10 -alkyl radical and / or alkoxy radical are bonded to an aromatic nucleus can be hydrogenated to the corresponding cycloaliphatic compounds, mixtures of two or several of these connections can be used. The aromatic compounds can be mononuclear or polynuclear aromatic compounds. The aromatic compounds contain at least one hydroxyl group which is bonded to an aromatic nucleus, the simplest compound of this group being phenol. The aromatic compounds preferably have one hydroxyl group per aromatic nucleus. The aromatic compounds can be substituted on the aromatic core or the aromatic core's by one or more alkyl and / or alkoxy radicals, preferably C _1-10 alkyl and / or alkoxy radicals, particularly preferably C _1-10 alkyl radicals, in particular Methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl radicals; among the alkoxy radicals are the C _1-8 alkoxy radicals, such as. B. methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, tert-butoxy radicals, preferred. The aromatic nucleus or the aromatic nuclei as well as the alkyl and alkoxy residues can optionally be substituted by halogen atoms, in particular fluorine atoms, or have other suitable inert substituents.

The compounds which can be hydrogenated according to the invention preferably have at least one, preferably one to four, in particular a C _1-10 -alkyl radical which is preferably located on the same aromatic nucleus as the at least one hydroxyl group. Preferred compounds are (mono) alkylphenols, it being possible for the alkyl radical to be in the o-, m- or p-position relative to the hydroxyl group. Para-alkylphenols, also referred to as 4-alkylphenols, are particularly preferred, the alkyl radical preferably having 1 to 10 carbon atoms and in particular being a tert-butyl radical. 4-tert-butylphenol is preferred. Polynuclear aromatic compounds which can be used according to the invention are, for example, β-naphthol and α-naphthol.

The aromatic compounds in which at least one hydroxyl group and preferably furthermore at least one optionally substituted C _1-10 -alkyl radical and / or alkoxy radical are bonded to an aromatic nucleus can also have several aromatic nuclei which have an alkylene residue, preferably a methylene group are linked. The linking alkylene group, preferably methylene group, can have one or more alkyl substituents, which can be C _1-20 alkyl radicals and preferably C _1-10 alkyl radicals, particularly preferred are methyl, ethyl, propyl, isopropyl, butyl, or tert-butyl radicals.

Each of the aromatic nuclei can have at least one hydroxyl group bound included. Examples of such compounds are bisphenols, which are described in 4-position via an alkylene radical, preferably a methylene radical, ver are knotted.

In the context of the process according to the invention, a phenol substituted with a C _1-10 -alkyl radical, preferably C _1-6 -alkyl radical, which is optionally substituted with an aromatic radical, or mixtures of two or more of these compounds is particularly preferably implemented .

In a further preferred embodiment of this method p-tert-butylphenol, bis (p-hydroxyphenyl) dimethylmethane or a mixture of it implemented.

Aromatic compounds in which at least one amino group is attached to one aromatic nucleus is bound

With the process according to the invention, aromatic compounds in which at least one amino group is bonded to an aromatic nucleus can also be hydrogenated to the corresponding cycloaliphatic compounds, mixtures of two or more of these compounds also being able to be used. The aromatic compounds can be mononuclear or polynuclear aromatic compounds. The aromatic compounds contain at least one amino group which is bonded to an aromatic nucleus. The aromatic compounds are preferably aromatic amines or diamines. The aromatic compounds on the aromatic nucleus or the aromatic cores or on the amino group can be substituted by one or more alkyl and / or alkoxy radicals, preferably C _1-20 alkyl radicals, in particular methyl, ethyl, propyl, isopropyl, Butyl, isobutyl, tert-butyl residues; among the alkoxy radicals are the C _1-8 alkoxy radicals, such as. B. methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, tert-butoxy radicals, are preferred. The aromatic nucleus or the aromatic nuclei as well as the alkyl and alkoxy residues can optionally be substituted by halogen atoms, in particular fluorine atoms, or have other suitable inert substituents.

The aromatic compound, in which at least one amino group is bonded to an aromatic nucleus, can also have several aromatic nuclei which are linked via an alkylene group, preferably a methylene group. The linking alkylene group, preferably methylene group, can have one or more alkyl substituents which can be C _1-20 alkyl radicals and preferably C _1-10 alkyl radicals, particularly preferably methyl, ethyl, propyl, isopropyl or butyl -, sec-butyl or tert-butyl residues.

The amino group bonded to the aromatic nucleus can also by one or two of the alkyl radicals described above may be substituted.

Particularly preferred compounds are aniline, naphthylamine, diaminobes zoles, diaminotoluenes and bis-p-aminophenylmethane or mixtures thereof.

CATALYSTS

The catalysts used according to the invention can be produced industrially are by applying ruthenium and optionally at least one Metal of I., VII. Or VIII. Subgroup of the periodic table on one suitable carrier. The application can be done by soaking the wearer in aqueous metal salt solutions, such as ruthenium salt solutions, by spraying appropriate metal salt solutions on the carrier or by other ge appropriate procedures can be achieved. As ruthenium salts for the production of Ruthenium salt solutions as well as metal salts of I., VII. Or VIII. Subgroup of the periodic table are the nitrates, nitrosyl nitrates, Halides, carbonates, carboxylates, acetylacetonates, chlorine complexes, nitrito complex or amine complexes of the corresponding metals, the nitrates and nitrosyl nitrates are preferred.  

In the case of catalysts which, in addition to ruthenium, also metals on the Contained carrier applied, the metal salts or metal salt solutions can be applied simultaneously or in succession.

The coated with the ruthenium salt or metal salt solution or ge impregnated supports are then dried, temperatures between between 100 ° C and 150 ° C are preferred. Optionally, these carriers can Temperatures between 200 ° C and 600 ° C, preferably 350 ° C to 450 ° C be calcined. The coated supports are then passed through Treatment in a gas stream containing free hydrogen at tempera doors between 30 ° C and 600 ° C, preferably between 150 ° C and 450 ° C activated. The gas stream preferably consists of 50 to 100 vol .-% H₂ and 0 to 50 vol .-% N₂.

If one or more other (s) are added to the carrier in addition to ruthenium Metal (s) of subgroup I, VII or VIII of the Periodic Table and if the application is carried out one after the other, the wearer can after each Apply or soak at temperatures between 100 ° C and 150 ° C be dried and optionally at temperatures between 200 ° C and 600 ° C can be calcined. The order in which the metal salt solution applied or soaked, can be chosen arbitrarily.

If one or more other metal (s) of I., VII. or VIII. Subgroup of the periodic table applied to the carrier, so are preferably platinum, copper, rhenium, cobalt, nickel or their Mixtures used.

The ruthenium or metal salt solution is in such an amount the carrier (s) is applied such that the active metal content is 0.01 to 30% by weight, preferably 0.01 to 10% by weight and in particular 0.01 to 5% by weight,  based on the total weight of the catalyst, of ruthenium and possibly other metal or other metals of I., VII. or VIII. Subgroup of the periodic table applied to the carrier lie.

The total metal surface area on the catalyst is preferably 0.01 to 10 m² / g, particularly preferably 0.05 to 5 m² / g and further before adds 0.05 to 3 m² / g of the catalyst. The metal surface is by means of that of J. LeMaitre et al. in "Characterization of Heterologous Catalysts", Edited by Francis Delannay, Mercel Dekker, New York 1984, pp. 310-324, described chemisorption.

In the catalyst used in the invention, the ratio is Surfaces of the at least one active metal and the catalyst carrier less than about 0.3, preferably less than about 0.1 and especially about 0.05 or less, with the lower limit at is about 0.0005.

CARRIER

The ver used to produce the catalysts used reversible carrier materials have macropores and mesopores. Here the term "macropores" refers to pores whose diameter is 50 nm exceeds, and the term "mesopores" denotes pores with a mitt diameter between about 2.0 nm and about 50 nm as is from the definition in Pure Applied Chem. 45, pp. 71ff, in particular p. 79 (1976) results.  

The carriers which can be used according to the invention have a pore distribution about 10 to about 50%, preferably about 15 to about 50%, more preferably about 15 to about 45% and especially about 30 to about 40% of the pore volume of macro pores with pore diameters in the range from approximately 50 nm to approximately 10,000 nm and about 50 to about 90%, preferably about 50 to about 85%, more preferably about 55 to about 85% and especially about 60 to about 70% of the pore volume of Mesopo ren with a pore diameter of about 2 to about 50 nm be formed.

Preferably, the surface of the carrier is about 50 to about 500 m² / g, more preferably about 200 to about 350 m² / g and in particular about 200 to about 250 m² / g of the carrier.

The surface of the carrier is by the BET method by N₂ ad sorption, especially according to DIN 66 131. The determination of the mean pore diameter and size distribution is done by Hg porosymmetry, especially according to DIN 66 133.

Although in principle all carrier materials known in the manufacture of catalysts rialien, d. H. which have the pore size distribution defined above activated carbon, silicon carbide, Aluminum oxide, silicon dioxide, titanium dioxide, zirconium dioxide, magnesium oxide, zinc oxide or mixtures thereof, more preferably aluminum oxide and Zirconium dioxide.

The catalysts used according to the invention show a high reactivity (high turn-over number), selectivity and service life. Using the invent According to the catalysts used in the hydrogenation, the Hy  Dration products obtained in high yield and purity, one subsequent cleaning is unnecessary. The turnover is practically quantitative. In a preferred embodiment, the hydrogenation product obtained can form of the present invention thus directly for further processing can be fed without having to be cleaned.

SOLVENT OR THINNER

In the process according to the invention, the hydrogenation can be carried out in the absence a solvent or diluent are carried out, d. H. it is not necessary to carry out the hydrogenation in solution.

However, a solvent or diluent is preferably used. Any suitable solvent or Diluents are used. The selection is not critical. For example, the solvents or diluents can also be low Contain amounts of water.

In the hydrogenation of an aromatic compound in which at least one Hydroxyl group is attached to an aromatic nucleus, close use suitable solvents or diluents:

Straight chain or cyclic ethers such as tetrahydrofuran or Dioxane and aliphatic alcohols in which the alkyl radical is preferably 1 has up to 10 carbon atoms, in particular 3 to 6 carbon atoms.

Examples of preferably usable alcohols are i-propanol, n-butanol, i-butanol and n-hexanol.  

Mixtures of these or other solvents or diluents can can also be used.

In the hydrogenation of an aromatic compound in which at least one Amino group attached to an aromatic nucleus include examples suitable solvents or diluents include the following:

Straight chain or cyclic ethers such as tetrahydrofuran or Dioxane, and ammonia and mono- or dialkylamines in which the Alkyl radical preferably has 1 to 3 carbon atoms, such as. B. methyl, Ethyl, propylamine or the corresponding dialkylamines.

Mixtures of these or other solvents or diluents can can also be used.

In both of the above embodiments, the amount of Lö used solvent or diluent not particularly limited and can be chosen as required, but such quantities are preferred to a 10 to 70 wt .-% solution to hydrie connection.

This is particularly preferred in the context of the method according to the invention Product formed in the hydrogenation of this process as a solvent used, optionally in addition to other solvents or diluents. In this case, part of the Pro Ductes are added to the compounds to be hydrogenated. Related to the weight of the aromatic compounds intended for hydrogenation is preferably 1 to 30 times, particularly preferably 5 to 20 times, in particular 5 to 10 times the amount of the hydrogenation product as Solvent or diluent added.  

HYDRATION

The hydrogenation is carried out at suitable pressures and temperatures leads. Pressures above 5 × 10⁶ Pa, preferably from, are preferred 1 × 10⁷ to 3 × 10⁷ Pa. Preferred temperatures are in a range from 50 to 250 ° C, preferably between 100 and 220 ° C.

The hydrogenation process can be carried out continuously or in the manner of a batch process driving. In the continuous process, one can Part of the hydrogenation product leaving the reactor to the reactor feed be fed before the reactor. Such an amount of the Reactor leaving hydrogenation product recycled as a solvent that the quantities specified in the subsection "solvents and diluents" conditions are achieved. The remaining amount of hydrogenation product is withdrawn.

With continuous process control, the amount for hydrogenation is provided connection or connections preferably about 0.05 to about 3 kg per liter of catalyst per hour, more preferably about 0.1 to about 1 kg per liter of catalyst per hour.

Any gases can be used as hydrogenation gases, the free what contain hydrogen and no harmful amounts of catalyst poisons, such as for example, CO. For example, reformer exhaust gases be applied. Pure hydrogen is preferably used as the hydrogenation gas turns.

Depending on the reaction conditions, in the case of the phenols and amines additionally substituted by at least one optionally substituted C _1-10 - and / or alkoxy radical, depending on the reaction conditions (temperature, solvent), the isomer ratio of cis to trans-configured products obtained can be in a wide range can be varied.

If an aromatic compound in the at least one amino group an aromatic nucleus is bound by means of the catalyst according to the invention should be hydrogenated, the hydrogenation can also in the presence of Ammonia or dialkylamines, for example methylamine, ethylamine, Propylamine or dimethylamine, diethylamine or dipropylamine performed will. Suitable amounts of ammonia or mono- or Dialkylamine used, preferably at about 0.5 to about 50 Parts by weight, particularly preferably from about 1 to about 20 Ge parts by weight, in each case based on 100 parts by weight of the hydrogenation provided connection or connections. Particularly preferred anhydrous ammonia or anhydrous amines are used.

Furthermore, the present invention relates to the use of a defi above nated catalyst for the hydrogenation of an aromatic compound in which at least one hydroxyl group is attached to an aromatic nucleus or for the hydrogenation of an aromatic compound in which at least one Amino group is bound to an aromatic nucleus, as well as the Carrying out the hydrogenation processes described above, suitable described catalyst itself.

The invention is described below with the aid of a few exemplary embodiments explained in more detail, with examples 1 to 7 relating to the hydrogenation of a aromatic compound in which at least one hydroxyl group is attached to one aromatic nucleus, and Examples 8 to 16 refer the hydrogenation of an aromatic compound in which at least one Amino group is bound to an aromatic nucleus.

EXAMPLES Preparation of the catalyst

A meso / macroporous alumina support in the form of 4 mm extru laten, which has a BET surface area of 238 m² / g and a pore volume of 0.45 ml / g was mixed with an aqueous ruthenium (III) nitrate solution, which had a concentration of 0.8% by weight. 0.15 ml / g (approx approximately 33% of the total volume) of the pores of the carrier had a through knife in the range from 50 nm to 10,000 nm and 0.30 ml / g (approx. 67% of the total pore volume) of the pores of the carrier had one pore knife in the range of 2 to 50 nm. That while drinking from Solution volumes absorbed by the carrier corresponded approximately to the pores volume of the carrier used.

The solution was then impregnated with the ruthenium (III) nitrate solution Carrier dried at 120 ° C and activated at 200 ° C in a water stream (reduced). The catalyst prepared in this way contained 0.05% by weight of ruthenium, based on the weight of the catalyst.

example 1

A 50% by weight solution of p-tert-butylphenol in THF was obtained poses. Then 2500 g / h of this solution with hydrogen 180 ° C and a total pressure of 2.6 × 10⁷ Pa through a Durchflußre actuator, which was filled with 3.2 l of the Ru catalyst described above, headed. After the solvent was distilled off, the hydrogenation had product has the following composition:

• - 99.9% cis, trans-4-tert-butylcyclohexanol
• - <0.01% p-tert-butylphenol

Example 2

The hydrogenation was described in the same manner as in Example 1 carried out, but 3500 g of 50 wt .-% p-tert-butylphenol solution solution in THF at 200 ° C were passed through the reactor. After this Distilling off the solvent had the following hydrogenation product Composition:

• - 99.8% cis, trans-4-tert-butylcyclohexanol
• - <0.01% p-tert-butylphenol

Example 3

The hydrogenation was carried out in the same manner as in Example 1 carried out, however, a 50 wt .-% solution of p-tert-Bu tylphenol used in i-butanol. After distilling off the solution The hydrogenation product had the following composition:

• - 67.5% trans-4-tert-butylcyclohexanol
• - 32.4% cis-4-tert-butylcyclohexanol
• - <0.01% p-tert-butylphenol

Example 4

2 kg of a solution of 50% by weight were placed in a 3.5 l autoclave. Bisphenol A in THF and 500 ml of the macroporous catalyst from Bei game 1 (0.4 wt .-% Ru on Al₂O₃) placed in a catalyst basket. Then was discontinuously at 150 ° C and 2 × 10⁷ Pa five Hydrogenated for hours. The conversion to the desired cycloaliphatic diol  The mixture of isomers was quantitative and the residual aromatic content was less than 0.01%.

Example 5

1.2 l of the catalyst prepared as described above were placed in a filled electrically heated flow reactor. Then was without previous activation at 2 × 10⁷ Pa and 160 ° C with the hydrogenation started by aniline. The hydrogenation was continuously in sump wisely carried out, with part of the hydrogenation discharge over a Um run pump returned and mixed with the feed before the reactor has been. Based on the amount of aniline, this was ten times the amount Hydrogenation product added as a solvent. At the head of the separator 500 to 600 l of H₂ / h were released. The continuously to the reactor amount of aniline carried corresponded to a catalyst load of 0.6 kg / l × h.

Depending on the reaction temperatures, the results for stationary The following product compositions:

Example 6

The hydrogenation was carried out as described in Example 5, with however, anhydrous ammonia was also metered in continuously. Based on 100% by weight of aniline, 10 parts by weight of ammonia added. Depending on the reaction temperatures, the result was: stationary reaction conditions the following product compositions:

Example 7

2 kg of a solution of 50% by weight were placed in a 3.5 l autoclave. Toluene diamine (2,4-; 2,6-diaminotoluene isomer mixture) in THF and 500 ml given the catalyst described above. Then was discontinuously hydrogenated at 150 ° C and 2 × 10⁷ Pa for five hours. The conversion to the desired cycloaliphatic diamine isomer mixture was quantitative and the residual aromatic content was less than 0.01%.

Claims (9)

1. A process for hydrogenating an aromatic compound in which at least one hydroxyl group is bound to an aromatic nucleus, or an aromatic compound in which at least one amino group is bound to an aromatic nucleus, in the presence of a catalyst which is the active metal ruthenium alone or together with at least one metal from subgroup I, VII or VIII of the periodic table in an amount of 0.01 to 30% by weight, based on the total weight of the catalyst, applied to a support, characterized in that 10 to 50% of the pore volume of the carrier of macropores with a pore diameter in the range from 50 nm to 10,000 nm and 50 to 90% of the pore volume of the carrier of mesopores with a pore diameter in the range from 2 to 50 nm are formed, the Sum of the pore volumes added up to 100%. 2. The method according to claim 1, characterized in that the carrier has a BET surface area of 50 to 500 m² / g. 3. The method according to at least one of the preceding claims, characterized characterized in that the relationship between the metal surface and the Carrier surface, measured according to BET, is in the range 0.0005 to 0.3. 4. The method according to at least one of the preceding claims, characterized characterized in that the at least one metal of I., VII. or VIII.  Sub-group of the periodic table platinum, copper, rhenium, cobalt, Nickel or a mixture of two or more thereof. 5. The method according to at least one of the preceding claims, characterized characterized in that the carrier activated carbon, silicon carbide, aluminum oxide, silicon dioxide, titanium dioxide, zirconium dioxide, magnesium oxide, Zinc oxide or a mixture of two or more thereof. 6. The method according to at least one of the preceding claims, characterized in that an aromatic compound in which at least one hydroxyl group is bound to an aromatic nucleus and which in addition to the at least one hydroxyl group at least one C _1-10 alkyl group or at least one C _{1 -10} alkoxy group or at least one C _1-10 alkyl group and at least one C _1-10 alkoxy group, which in turn may each be substituted, is bonded to an aromatic nucleus or an aromatic compound in which at least one amino group is attached to an aromatic nucleus Nucleus is bonded, in addition to at least one amino group at least one C _1-10 alkyl group or at least one C _1-10 alkoxy group or at least one C _1-10 alkyl group and at least one C _1-10 alkoxy group, each of which in turn may be substituted, is bound to an aromatic nucleus, is hydrogenated. 7. The method according to at least one of the preceding claims, characterized characterized in that the hydrogenation in the presence of a solution or Diluent is carried out. 8. Use of a catalyst as in at least one of the claims Defined 1 to 5, for the hydrogenation of an aromatic compound in which at least one hydroxyl group bound to an aromatic nucleus  is, or for the hydrogenation of an aromatic compound, in which mind at least one amino group is attached to an aromatic ring. 9. catalyst as defined in at least one of claims 1 to 5, suitable for carrying out hydrogenation processes, as in at least one egg nem of claims 1 to 8 defined.