Description

The present invention relates to a method for

producing formed catalysts or formed catalyst supports, to the catalysts or catalyst supports obtainable thereby and a method for the catalytic treatment of carbon

compounds, preferably for the oxidation or reduction, particularly hydrogenation, of carbon compounds,

preferably aromatic hydrocarbons, in particular

nitroaromatics or unsaturated hydrocarbons using a

catalyst prepared according to the present invention.

The production of spherical catalysts and catalyst supports is widely disclosed in the literature, including the production of oxidic supports by dropping acidic hydrogels into different solutions.

US 4,198,318 discloses the production of spherical

AI ₂ O ₃ supports by dropping an acidic hydrogel into an aqueous ammoniacal solution in the presence of a surface active agent, in particular a non-ionic surfactant. DE 403 50 89 discloses a comparable dropping process using a vibrating nozzle plate.

DE 102 16 256 discloses a pre-treatment of an

acidified aluminium oxide suspension with an organic phase before dropping it into an ammoniacal solution.

WO 02/094429 discloses an alternative possibility to produce spherical pellets, wherein a suspended ceramic mass and stabilizing components, for example starch, are pumped into paraffin.

US 6,251,823 discloses dropping of a mixture comprising a polysaccharide, hydrogels (comprising Al, Zr, Si, B, Ti and combinations thereof) and optional additives and/or fillers into an aqueous solution of a multivalent ion, such as Ca ²⁺ , Al ³⁺ , Mg ²⁺ , Ba ²⁺ and Sr ²⁺ .

EP 1 331 033 discloses the production of a metal rich bulk metal catalyst using technology similar to the technology described in US 6,251,823.

The use of multivalent ions is, however,

disadvantageous, since the catalyst product still

contains these ions as contaminants.

Spherical mouldings produced by dropping

technologies according to the state of the art may have a relatively high specific porosity. Usually, however, their diameter is limited. Mouldings with a large

diameter and the same composition are usually only available by granulation (build-up granulation of

powders, granulation on the basis of extruded mouldings) .

The following overview shows the difference between the conventional AI ₂ O ₃ mouldings prepared by dropping and granulation .

Table 1

Z1100 °C = calcined at 1100 °C A disadvantage of granulation technology according to the state of the art is the obtained relatively wide particle size distribution of the moulding fractions produced. To provide a narrower particle size

distribution it is necessary to remove significant parts of the obtained fractions. In contrast thereto, mouldings produced by dropping according to the state of the art, commonly, have a more narrow particle size distribution, but unfortunately diameters similar to the diameters of mouldings produced by granulation cannot be obtained without significant loss of mechanical stability and increasing abrasion.

The problem underlying the present invention is to provide a method for producing catalysts or catalyst supports which overcome the above-identified problems and disadvantages, in particular, which are able to provide formed, in particular spherical or extrudate-like, catalysts and/or catalyst supports, which can be provided without contamination of multivalent ions with a narrow particle size distribution and - within a wide range of different particle sizes - for a given predetermined particle size including comparable large particle sizes. Furthermore, it is desired to provide a cost-reduced and simple process for providing formed catalysts or catalyst supports, which in addition is able to provide alkali- or earth alkali-reduced or -free supports or catalysts.

Finally, it is also desired to provide methods to

specifically and in an individual on demand fashion produce catalysts over a wide range of sizes, hence to produce tailor-made catalyst sizes.

The problem underlying the present invention is solved by a method for producing formed, in particular spherical or extrudate-like, catalysts or catalyst supports, comprising the following steps:

a) providing a suspension comprising at least one

polysaccharide and at least one precursor of a catalyst or of a catalyst support,

b) introducing the suspension of step a) into an acidic medium, in particular an acidic solution, comprising at least one monovalent acid to form mouldings, preferably an acid medium having a pH value lower than 2.0.

c) drying the mouldings obtained in step b) , and d) calcining the mouldings dried in step c) at

temperatures from 350 to 1300 °C to obtain the formed, preferably spherical or extrudate-like, catalysts or catalyst supports.

The technical problem underlying the present

invention is solved preferably according to the teaching of the independent claims.

In the context of the present invention a suspension is provided comprising at least one polysaccharide and at least one precursor of catalyst or one precursor of a catalyst support. Thus, a suspension is prepared

comprising at least one polysaccharide and at least one precursor of a catalyst or of a catalyst support, wherein in the context of the present invention the precursor means that a catalyst material or a catalyst support material is used in providing the suspension. Thus, the term "precursor" is used interchangeably to the term "material". Accordingly, a suspension is prepared

comprising at least one polysaccharide and at least one catalyst material or at least one catalyst support material. Such a material may preferably be used in form of a powder, preferably a wet powder, dry sludge or filter cake.

In the context of the present invention the term "suspension" refers to a heterogenic mixture of a liquid medium and solid particles dispersed therein. The term

"suspension" refers in a preferred embodiment to

suspensions with a high viscosity. In another preferred embodiment the term "suspension" refers to suspensions with a low viscosity. In one preferred embodiment of the present invention the term "suspension" also refers to highly viscose suspensions, such as a paste or pasty masses .

Preferably, in step a) of the present invention, the suspension is provided by mixing a liquid medium, which may be water, the polysaccharide and the precursor. Said liquid medium and polysaccharide may be mixed first after which the obtained mixture is mixed with the precursor resulting in the suspension.

In the context of the present invention the term "moulding" means a defined shape or form of a material being the result of a forming or shaping process. The obtained mouldings preferably have a spherical shape. In another preferred embodiment they have an extrudate-like shape. In another embodiment the mouldings have a trilobe or cylindrical shape.

In the context of the present invention the term "monovalent acid" defines an acid as a compound which donates one proton to another compound, for instance to water. In the context of the present invention only

Bronsted acids are meant, when the term "acid" is used.

In the context of the present invention the term "mineral acid" means acids derived from one or more inorganic compound. In the context of the present invention the term "organic acid" means an organic compound with acidic properties .

In the context of the present invention the term "surface active substance" means a substance which lowers or strengthens the surface tension of a medium in which it is dissolved and/or the interfacial tension towards another phase.

Under a narrow particle size distribution is

understood that more than 95 % of all particles of a given particle population have a diameter with a maximum divergence of 50 %, preferably 40 %, in particular 30 %, in particular 20 % of the average diameter of said population. Under a broad particle size distribution is understood that less than 95 % of all particles of a given particle population have a diameter with a maximum divergence of 50 %, preferably 40 %, in particular 30 %, in particular 20 % of the average diameter of said population .

Under a narrow particle size distribution is

preferably understood that more than 95 % of all

particles of a given particle population have a diameter with a maximum divergence of 1 mm. Under a broad particle size distribution is preferably understood that less than 95 % of all particles of a given particle population have a diameter with a maximum divergence of 1 mm.

The particle size distribution is determined by digital image processing, in particular using the

Camsizer® instrument by Retch Technology GmbH,

Haan/Dusseldorf, Germany.

The particle size distribution can also be

determined by conventional sieve analysis. In the context of the present invention the term "polysaccharide with a variable content of methoxyl groups" means that the polysaccharides of a

polysaccharide fraction have different contents of methoxyl groups .

In the context of the present invention it has to be understood that all numerical values and numerical ranges given for constituents of a mixture have to add up to 100 % by weight, most preferably not to exceed 100 % by weight.

In a preferred embodiment the present invention provides a method, wherein catalysts or catalyst supports can be produced in a defined shape by providing in a first step a suspension which comprises a polysaccharide and a precursor of a catalyst or a precursor of a

catalyst support. In a second step the suspension of the first step is introduced into an acidic medium,

preferably an acidic solution, with a pH value below 5.0, preferably below 2.0, most preferably below 1.5

comprising a monovalent acid, which is either dissolved in water, that means is present in diluted form or is present in its pure form. In a subsequent third step, the formed mouldings of step b) are dried and in a fourth step are calcined at temperatures from 350 to 1300 °C in order to obtain the desired formed catalysts or formed catalyst supports.

The present invention allows producing catalyst precursors and catalysts in a predefined form, wherein the form, the size, the porosity, the diameter, the particle size distribution, the bulk-crush strength and other physical and physicochemical parameters can be varied and obtained in a predefined way. Thus, the present invention provides to the skilled person the knowledge that by introducing a suspension according to the present invention into an acidic medium according to the present invention, it is possible by varying

different process conditions and using different

compositions of the substances to obtain the desired product characteristics.

Thus, one advantage of the methods according to the present invention is the wide variety of mouldings which can be obtained thereby. The methods are not limited to the form, particle size and porosity of the mouldings.

Mouldings with the desired physical properties may preferably be obtained by adjusting the different

parameters of the methods according to the present invention. For instance, varying the particle size distribution according to the present invention allows to modify the bulk density. In a preferred embodiment of the present invention catalysts and catalyst supports can be prepared having a narrow particle size distribution.

Further, varying the maintenance time of the mixture obtained in step b) allows to vary the porosity and/or bulk density and/or the size of the obtained mouldings.

Furthermore, the catalysts and catalyst supports prepared by methods according to the present invention can be easily produced with low costs.

Another advantage of the present invention is to provide a method to produce alkali- or earth alkali-free or -reduced formed catalysts and catalyst supports.

Furthermore, the preferred use of formic acid obviates washing of the obtained mouldings, because the elimination or reduction of undesired cations and nitrate ions is not necessary.

Furthermore, the preferred addition of, preferably small amounts, of commercially available polyelectrolytes , preferably polyacrylamides , into the acidic medium increases the viscosity of said medium and enables the production of particularly large mouldings.

In a preferred embodiment to obtain larger diameter, preferably spherical, mouldings a pump-nozzle-system is used .

In a preferred embodiment of the present invention the polysaccharide in step a) is an alginate or a

pectine .

In a preferred embodiment of the present invention the polysaccharide in step a) , preferably the alginate or the pectine, has a variable content of methoxyl groups. The content of methoxyl groups in the alginate or the pectine, or generally in the polysaccharides, can be adjusted in a conventional manner and according to the requirements the alginates and the pectine have to fulfill .

In a preferred embodiment of the present invention the alginate is sodium alginate.

In a preferred embodiment of the present invention the concentration of the polysaccharide in the suspension in step a) is from 5 to 100 g/1, preferably from 10 to 80 g/1, preferably from 20 to 60 g/1 and in particular from 25 to 40 g/1 (based on the total volume of the suspension) .

In a preferred embodiment of the present invention the precursor of the catalyst or the precursor of the catalyst support is selected from the group consisting of metal oxide, metal hydroxide, alkaline metal carbonate, metal hydrogen carbonate, metal silicate, metal

zirconate, metal aluminate, metal titanate, metal

chromite, metal alumino-silicate, metal carbide, metal boride, metal nitride, metal nitrate, metal acetate, metal oxalate, metal sulphide, metal sulphate and metal phosphate .

In a preferred embodiment of the present invention the precursor of the catalyst or the precursor of the catalyst support is selected from the group consisting of metal oxide, metal hydroxide, alkaline metal carbonate, metal hydrogen carbonate, metal silicate, metal

zirconate, metal aluminate, metal titanate, metal

aluminium-silicate and metal nitrate.

In a furthermore preferred embodiment of the present invention the precursor of the catalyst or the precursor of the catalyst support is selected from the group consisting of metal oxide, metal hydroxide, metal

silicate, metal aluminate and metal aluminosilicate .

In a preferred embodiment of the present invention the catalysts or the catalyst support prepared by a method of the present invention is selected from the group consisting of AI ₂ O ₃ , T1O ₂ , Zr0 ₂ , alumino-silicate, zeolithe and perovskite.

In a preferred embodiment of the present invention the metal of the precursor of the catalyst or the

precursor of the catalyst support is selected from the group consisting of Na, K, Mg, Ca, Sr, Ba, Ti, Zr, V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Zn, B, Al, Si, Ge, Sn and Pb .

In a preferred embodiment of the present invention the metal of the precursor of the catalyst or the

precursor of the catalyst support is selected from the group consisting of Ti, Zr, Al and Si.

In a preferred embodiment of the present invention the concentration of the precursor of the catalyst or the precursor of the catalyst support in the suspension is from 50 to 500 g/1, preferably from 100 to 400 g/1 and in particular from 250 to 500 g/1 (based on the total volume of the suspension) .

According to the present invention the suspension provided in step a) is introduced in step b) into an acidic medium, preferably acidic solution, wherein the obtained mixture is kept for a maintenance time

sufficient to form mouldings in said step b) .

In a preferred embodiment of the present invention the monovalent acid is a mineral acid or organic acid.

In a preferred embodiment the acidic medium in step b) consists of, essentially consists of or contains at least one monovalent mineral acid, at least one

monovalent organic acid or both.

In a preferred embodiment of the present invention the monovalent acid can be selected from the group consisting of HC1, HBr, HI, HNO ₃ , methanesulfonic acid, formic acid, acetic acid. Preferably, the monovalent acid can be selected from the group consisting of HBr, HI, HNO ₃ , methanesulfonic acid, formic acid, acetic acid. In a preferred embodiment of the present invention the monovalent acid is HNO ₃ . In a preferred embodiment of the present invention the monovalent acid is formic acid.

In a preferred embodiment of the present invention the monovalent acid is selected from the group consisting of nitric acid, formic acid and acetic acid.

In a preferred embodiment of the present invention the monovalent acid, in particular the monovalent mineral acid, may be a diluted monovalent acid, in particular diluted monovalent mineral acid, in particular diluted monovalent organic acid. In a particularly preferred embodiment the monovalent acid is diluted nitric acid. In a furthermore preferred embodiment the monovalent acid is diluted formic acid. In a furthermore preferred

embodiment the monovalent acid is diluted acetic acid.

In a preferred embodiment of the present invention the pH value of the acidic medium is lower than 5.0, preferably lower than 3.0, in particular lower than 2.0 and most preferably lower than 1.5 and preferably lower than 1.0.

In a preferred embodiment the acidic medium in step b) is a suspension or a solution, preferably an aqueous acid medium, most preferably an aqueous solution or aqueous suspension.

In a preferred embodiment of the present invention the acidic medium in step b) contains at least one further ingredient.

In a preferred embodiment of the present invention the at least one further ingredient is a multivalent ion. Within the present specification, a "multivalent" ion means an ion having a charge of 2 or higher. Preferably, the multivalent ion is a multivalent cation, that is to say an ion having a charge of 2+ or higher.

In the context of the present invention a

multivalent ion is also a bivalent ion.

The multivalent ion which can be present in the acidic medium of step b) is preferably selected from the group consisting of Ca ²⁺ , Al ³⁺ , Mg ²⁺ , Ba ²⁺ and Sr ²⁺ . In a preferred embodiment, however, the suspension prepared in step a), the acidic medium used in step b) or both, i.e. the suspension used in step a) and the acidic medium used in step b) , do not comprise multivalent ions.

In a preferred embodiment of the present invention the concentration of the multivalent ion is 0.05 to 5 % by weight, preferably 0.1 to 4 % by weight, preferably 0.2 to 2 % by weight and in particular 0.3 to 1 % by weight (based on the total weight of acidic medium) .

In a furthermore preferred embodiment of the present invention the at least one further ingredient is a surface active substance. Such a surface active substance may be advantageously used to adjust adhesive forces between the obtained mouldings .

In a preferred embodiment of the present invention the concentration of the surface active substance is 0.1 to 35 % by weight, preferably 0.2 to 20 % by weight, preferably 0.3 to 10 % by weight and in particular 0.4 to 1 % by weight (based on the total weight of acidic medium) .

In a preferred embodiment of the present invention the surface active substance is a ionic or non-ionic substance .

In a furthermore preferred embodiment of the present invention the at least one further ingredient is a hydrocarbon, in particular a non-functionalised

hydrocarbon. The use of a hydrocarbon in the acidic medium used in the present invention may be

advantageously considered for adjusting the adhesive forces between the formed mouldings.

In a preferred embodiment of the present invention the hydrocarbon is present in a concentration from 0.1 to

35 % by weight, preferably 0.2 to 20 % weight, preferably 0.3 to 10 % by weight and in particular 0.4 to 1 % by weight (based on the total weight of acidic medium) .

In a furthermore preferred embodiment of the present invention the at least one further ingredient is a viscosity increasing additive.

In a preferred embodiment of the present invention the viscosity increasing additive is preferably a polyelectrolyte, preferably a cationic polyacrylamide, most preferred Superfloc C-496.

According to the present invention the viscosity increasing additive is preferably used for increasing the viscosity, in particular to obtain mouldings with a larger diameter and the same or a greater stability than the mouldings according to the state of the art within a specific range which in itself can be determined by conventional methods.

In a preferred embodiment of the present invention the content of the viscosity increasing additive is from 0.1 to 2 % by weight, preferably from 0.1 to 1.8 % by weight, preferably 0.1 to 1.5 % by weight, preferably from 0.2 to 1.5 % weight and in particular from 0.2 to 1.0 % by weight (based on the total weight of the acidic medium) .

In a further preferred embodiment of the present invention the at least one further ingredient is a suspended solid ingredient. In a preferred embodiment of the present invention the concentration of suspended solid ingredients in the acidic suspension used in step b) is 0.01 to 15 % by weight, preferably 0.1 to 15 % by weight and in particular 1 to 15 % by weight, preferably 1 to 10 % by weight, preferably 1.5 to 10 % by weight and in particular 2 to 10 % by weight (based on the total weight of the acidic medium) . The suspended solid

ingredient may preferably be an inert material, such as a catalyst support material, e.g. AI ₂ O ₃ .

In a preferred embodiment of the present invention the acidic medium used in step b) may contain one or more of the above-identified further ingredients, e.g. one or more of the group consisting of a multivalent ion, a surface active ingredient, a hydrocarbon, a viscosity increasing additive and a solid suspended ingredient. In a preferred embodiment of the present invention the acidic medium used in step b) is an aqueous acidic solution comprising at least one monovalent acid and a viscosity increasing additive, in particular a

polyelectrolyte, preferably in an amount from 0.1 to 2 % by weight (based on the total weight of the acidic medium) .

In a preferred embodiment the methods of the present invention are carried out ammonium- and ammoniac-free, in particular the suspension provided in step a) or the acidic medium in step c) or both are free of ammoniac and ammonium.

In a preferred embodiment the introducing in step b) is effected by dropping. Accordingly, in this embodiment the suspension is introduced into the acidic medium without exerting pressure.

In a preferred embodiment of the present invention the dropping is effected by a sieve screen, a rotating spray head or a capillary tube.

In a preferred embodiment of the present invention the introducing is effected by pressuring the suspension into the solution, for instance by means of a nozzle or nozzle plate under pressure. Preferably, the nozzle is suitable to form mouldings with a spherical, trilobe, extruded or cylindrical form.

In a preferred embodiment the suspension is pumped by hydraulic impulses or static pressure through a nozzle which can be a single nozzle or as nozzle plate.

In a preferred embodiment of the present invention the nozzle or nozzle plate is located, preferably vertically, above the surface of the acidic medium. In a preferred embodiment of the present invention the nozzle or nozzle plate is located, preferably

vertically, below the surface of the acidic medium and therefore allows to directly introduce the suspension into the acidic medium.

In a preferred embodiment of the present invention the suspension is dropped into the acidic medium, whereby the distance of the break-off point, i.e. the position at which individually recognisable drops are formed from the suspension, to the surface of the acidic medium of step b) is from 0.3 cm to 100 cm, preferably from 1 cm to 70 cm, preferably from 5 cm to 50 cm and in particular from 10 cm to 20 cm.

In a preferred embodiment of the present invention the mouldings obtained in step b) are separated from the acidic medium before they are dried in step c) .

In a preferred embodiment of the present invention the mouldings formed in step b) are kept in the acidic medium for a maintenance time from 3 seconds to 360 minutes, preferably from 1 minute to 300 minutes,

preferably 5 minutes to 100 minutes and in particular from 15 to 30 minutes.

In a preferred embodiment of the present invention the mouldings obtained in step b) are washed before step c) in a step b') with a solvent, preferably with water.

In a preferred embodiment of the present invention the drying in step c) is carried out at temperatures from 90 °C to 350 °C, preferably 90 to 180 °C, preferably from 100 °C to 150 °C and in particular from 110 °C to 120 °C.

In a preferred embodiment of the present invention the calcining of the mouldings dried in step c) is carried out at temperatures from 350 to 1300 °C, preferably from 350 °C to 1200 °C, preferably from 350 °C to 1000 °C and in particular from 900 °C to 1100 °C.

In a preferred embodiment of the present invention the catalysts or the catalyst supports obtained according to the present invention is further processed by

impregnation, thermal treatment, hydrothermal treatment, reductive treatment or by combinations thereof.

In a preferred embodiment of the present invention the calcining in step c) is carried out in inert, oxidative or reductive conditions or in combinations thereof .

The technical problem is furthermore solved by a formed, preferably spherical or extrudate-like, catalyst or catalyst support obtainable by a method according to the present invention.

According to a preferred embodiment of the present invention a catalyst precursor is used in step a) of the present method and according to the present teaching a formed catalyst is prepared. Thus, the present invention relates to a formed catalyst obtainable according to the present invention.

In a preferred embodiment the invention provides a process, wherein in step a) a precursor of a catalyst support is used and according to the present teaching a formed catalyst support is prepared. Thus, the present invention also relates to a formed catalyst support obtainable according to the present invention.

In a further preferred embodiment of the present invention a catalyst support obtainable according to the present teaching is used to prepare in a conventional manner a catalyst therefrom. Thus, in this embodiment the present invention also relates to a catalyst obtainable according to the present invention, in particular obtainable by preparing a catalyst support according to the present invention and in a conventional manner preparing a catalyst therefrom.

In a preferred embodiment the catalysts or the catalyst supports of the present invention are activated in a hydrogen stream.

The present invention also provides a process for catalytically treating carbon compounds, wherein the carbon compounds are treated under suitable conditions and in contact with the catalyst obtainable by a method according to the present invention or a catalyst

according to the present invention so as to obtain the desired treated products.

In the context of the present invention, carbon compounds are preferably hydrocarbons or derivatives of hydrocarbons. Preferably hydrocarbons contain only carbon and hydrogen and may be aliphatic hydrocarbons, in particular alkanes, alkenes, alkynes, including cyclic forms thereof. Hydrocarbons may also be aromatic

hydrocarbons. Derivatives of hydrocarbons contain in addition to C- and H-atoms functional groups, such as halogen, alcoholic, amino, carboxylic, ester or amid groups. They may also contain aldehyd, ketone or ether groups .

In a particularly preferred embodiment the

catalytical treatment is an oxidation.

Accordingly, the present invention provides a method for the catalytic oxidation of carbon compounds, i.e. oxidisable carbon compound educts, such as derivatives of hydrocarbons, for instance hydrocarbons comprising alcoholic, amino, keto or aldehyd functions or

unsaturated or saturated hydrocarbons, including

cycloalkanes , under suitable oxidative conditions and in contact with the catalyst according to the present invention or obtainable according to a method of the present invention so as to obtain the oxidised

derivatives of the educts.

In a furthermore preferred embodiment the present invention relates to a method for the catalytic

reduction, in particular hydrogenation, of carbon

compounds, i.e. reducible carbon compound educts, such as unsaturated hydrocarbons or derivatives of hydrocarbons, wherein the carbon compounds are hydrogenated under suitable reductive hydrogenation conditions, particularly in the presence of hydrogen, and in contact with the catalyst of the present invention or obtainable by a method according to the present invention. In a preferred embodiment of the present invention the carbon compounds may be unsaturated and non-functionalised hydrocarbons for instance alkynes.

In a furthermore preferred method of the present invention the carbon compounds to be reduced are

derivatives of hydrocarbons, in particular functionalised hydrocarbons, such as functionalised aromatic or

aliphatic hydrocarbons, preferably with alcoholic, nitro, carboxylic, keto or aldehyd functions, such as

heteroaromatics , nitroaromatics , where said

functionalised hydrocarbons are hydrogenated under suitable hydrogenating conditions and in contact with a catalyst obtainable by a method according to the present invention or a catalyst according to the present

invention .

Further preferred embodiments are the subject matter of the subclaims. Further advantages of the present invention are illustrated by way of the following examples and the only figure .

The figure shows the particle size (x-axis: diameter of particles in mm, y-axis: cumulative proportion less than indicated size) distribution of the present catalyst supports in comparison to a reference.

Examples :

Example 1

Production of a Catalyst Support by Dropping a

Commercially Available AI ₂ O ₃ Precursor into a Diluted HNO ₃ Solution

35.2 g of sodium alginate was dissolved in 2.35 1 water under stirring and subsequently 600 g of a

commercially available boehmite was added. A flowable suspension was produced by homogenising the suspension with a suitable homogeniser, for example ULTRA- URRAX®. Subsequently, the suspension was pumped into a suitable drop head and was dropped into a 0.25 M aqueous HN03 solution from a height of about 15 cm. The geometry of the arrangement caused an immediate formation of

spherical mouldings at the time the drops entered the solution. The mouldings were kept for 20 minutes in the HN03 solution. The mouldings were washed optionally In 10 1 water for about 20 minutes. Subsequently, the mouldings were dried at 120 °C for 15 hours and calcined at 1000 °C for three hours. The obtained catalyst support can be processed further.

Example 2

Production of a Catalyst Support by Dropping a

Commercially Available AI ₂ O ₃ Precursor into a Diluted

HN03/Polyacrylamide Solution 15 g of sodium alginate was dissolved in 1 1 water under stirring and subsequently 256 g of a commercially available boehmite was added. A flowable suspension was produced by homogenising the suspension with a suitable homogeniser, for example ULTRA- URRAX®. Subsequently, the suspension was pumped into a suitable drop head and was dropped into a 0.25 M aqueous HNO ₃ solution comprising 0.5 % by weight of a commercially available

polyelectrolyte Superfloc C-496 from a height of about 15 cm. The geometry of the arrangement caused an

immediate formation of spherical mouldings at the time the drops entered the solution. The mouldings were kept 20 minutes in the HNO ₃ solution. The mouldings were washed optionally in 10 1 water for about 20 minutes. Subsequently, the mouldings were dried at 120 °C for 15 hours and calcined at 1000 °C for three hours. The obtained catalyst support can be processed further.

Example 3

Production of a Catalyst Support by Dropping a

Commercially Available AI ₂ O ₃ Precursor into a Diluted

HCOOH Solution

35.2 g of sodium alginate was dissolved in 2.35 1 water under stirring and subsequently 600 g of a

commercially available boehmite was added. A flowable suspension was produced by homogenising the suspension with a suitable homogeniser, for example ULTRA-TURRAX®. Subsequently, the suspension was pumped into a suitable drop head and was dropped into a 1 M aqueous HCOOH solution from a height of about 15 cm. The geometry of the arrangement caused an immediate formation of

spherical mouldings at the time the drops entered the solution. The mouldings were kept for more than 20 minutes in the HCOOH solution. The mouldings were washed optionally in 10 1 water for about 20 minutes.

Subsequently, the mouldings were dried at 120 °C for 15 hours and calcined at 1000 °C for three hours. The obtained catalyst support can be processed further.

Example 4

Production of a Catalyst Support by Dropping a

Commercially Available AI ₂ O ₃ Precursor and -Αΐ ₂ θ ₃ into a Diluted HN0 ₃ Solution

35.2 g of sodium alginate was dissolved in 2.35 1 water under stirring and subsequently 600 g of a

commercially available boehmite was added. Subsequently, 60 g of -Αΐ ₂ θ ₃ powder was added. A flowable suspension was produced by homogenising the suspension with a suitable homogeniser, for example ULTRA- URRAX®.

Subsequently, the suspension was pumped into a suitable drop head and was dropped into a 0.25 M aqueous HNO ₃ solution from a height of about 15 cm. The geometry of the arrangement caused an immediate formation of

spherical mouldings at the time the drops entered the solution. The mouldings were kept for 20 minutes in the HNO ₃ solution. The mouldings were washed optionally in 10 1 water for about 20 minutes. Subsequently, the mouldings were dried at 120 °C for 15 hours and calcined at 1000 °C for three hours. The obtained catalyst support can be processed further.

Example 5

Production of a Nickel-Containing Catalyst by Dropping a Nickel-Containing Precipitation Product into a Diluted HNO3 Solution

122 g of sodium alginate was dissolved in 8.7 1 water under stirring and subsequently 7.6 kg of a wet NiAl-containing precipitation product was added which was produced according to the state of the art and the ash content at 800°C thereof is about 16 % by weight. A flowable suspension was produced by homogenising the suspension with a suitable homogeniser equipment, for example ULTRA- URRAX®. Subsequently, the material was pumped into a suitable drop head and was dropped into a

0.25 M aqueous HNO ₃ solution from a height of about

15 cm. The geometry of the arrangement caused an

intermediate formation of spherical mouldings at the time the drops entered the solution. The mouldings were kept for 20 minutes in the HNO ₃ solution. The mouldings were washed optionally in 10 1 water for about 20 minutes.

Subsequently, the mouldings were dried at 120 °C for 15 hours and calcined at 350°C for three hours. The obtained oxidic catalyst can be used after activation in a hydrogen stream for appropriate applications.

Example 6

Production of a Catalyst Support by Pressing a

Commercially Available AI ₂ O ₃ Precursor into a Diluted HNO ₃ Solution

35.2 g of sodium alginate was dissolved in 1.2 1 water and subsequently 600 g of a commercially available boehmite was added. The production of a paste-like suspension was produced by homogenising the paste-like suspension with a suitable homogeniser equipment, for example ULTRA-TURRAX®. Subsequently, the material was pressed with a suitable pump through a formative

cylindrical nozzle (diameter 4.5 mm) directly into a 0.25 M aqueous HNO ₃ solution, i.e. below the surface of the solution. The geometry of the arrangement caused an intermediate formation of extrudate-like mouldings while entering the solution. The mouldings were kept for 20 minutes in the HNO ₃ solution. Subsequently, the mouldings were washed optionally in 10 1 water for about 20 minutes. Subsequently, the mouldings were dried at 120 °C for 15 hours and calcined at 1000 °C for three hours. During the preparation process the extrudate-like

mouldings are obtained in particle sizes of several mm to cm and can be separated in desired fractions by a

suitable sieve arrangement. The obtained catalyst support can be processed further.

Example 7

Comparison Between the Catalyst and Catalyst Supports According to the Present Invention and the State of the Art

As is evident from Table 2, the physical properties of the catalyst supports according to the present

invention are comparable to commercially available catalyst supports produced by granulation. Thus, the present process allows to produce catalyst supports in spherical shape.

Table 2

WPA: wide pore alumina (AI ₂ O ₃ precursor, pseudoboehmite) , SD: bulk density, BD: burst pressure

In the Figure, the different particle size

distributions of the catalyst supports according to the present invention in comparison with a reference

according to the state of the art is shown. The catalyst supports according to the present invention show a narrow particle size distribution, in particular narrower particle size distribution than the granulated catalyst supports. The average diameter of the catalyst support according to the present invention is dependent on the parameters selected during the preparation and can be adjusted, if desired.

Hydrogenation experiments

The 4 catalyst supports mentioned in Table 2 were used in preparing catalysts which were then used in hydrogenation experiments, in the following way.

The catalyst support in question was impregnated with an aqueous Pd( 0 ₃ )2 solution up to a final palladium content in the catalyst of 0.30 wt . % . Said impregnation and and pre-drying of the impregnated support were carried out in a moving bed. Subsequently, the catalyst was dried at 120 °C for 8 hours and calcined at 450 °C for 3 hours inside a fixed bed under oxidic conditions (air) .

The catalyst in question was utilized, after

activation in a hydrogen stream at 120 °C, in a

hydrogenation process. The hydrogenation experiments were carried out under the following conditions: hydrogenation of a mixture of 3% isoprene / 3% styrene / 1% indene / 75 ppm S (sulfur) as hexanthiole residue: C6H12; P = 40 bar,

LHSV = 4 v/vh, GHSV = 2000 v/vh. As can be seen from Table 3 below, the catalysts wherein the catalyst

supports originated from Examples 1, 2 and 6,

respectively, which are in accordance with the present invention, showed a much higher conversion than the reference catalyst. Table 3

catalyst support palladium (g/1) conversion of from catalyst used styrene after 72 in hydrogenation hours (%)

Example 1 1.7 >90

Example 2 1.6 >90

Example 6 1.35 >90

Axens / SPH 531 1.7 82

(conventional

support,

reference)