EP2872599A1

EP2872599A1 - Process for preparing hydrocarbons from carbon dioxide and hydrogen, and a catalyst useful in the process

Info

Publication number: EP2872599A1
Application number: EP13735333.0A
Authority: EP
Inventors: Manfred Baerns; Uwe Rodemerck; Quido Smejkal; Axel BARKSCHAT; Martin HOLENA; David Linke; Martina Marschall
Original assignee: Wagner Edmund Dr-Ing
Current assignee: Wagner Edmund Dr-Ing
Priority date: 2012-07-13
Filing date: 2013-07-12
Publication date: 2015-05-20
Also published as: WO2014009534A1; EP2684936A1; US20150197462A1

Abstract

The invention relates to a process for preparing hydrocarbons from carbon dioxide and hydrogen by reaction of carbon dioxide with hydrogen in the presence of a specific catalyst. The process of the invention can be used to form C₅-C₁₅ hydrocarbons that are of interest as fuels (petrol, diesel, kerosene), with very high selectivity. The process additionally and very selectively produces C₂-C₄ hydrocarbons, which can be used as valuable feedstocks in the chemical industry. The process achieves a high CO₂ conversion even without recycling of excess carbon dioxide. According to a further aspect, the invention relates to the catalysts as such.

Description

A process for producing hydrocarbons from carbon dioxide and hydrogen and a catalyst useful in the process

Field of the invention

The present invention relates to a method for

Production of hydrocarbons from carbon dioxide and hydrogen, in which carbon dioxide with hydrogen in

Presence of a specific catalyst is implemented. With the method according to the invention can be used as fuels

(Gasoline, diesel, kerosene) interesting C5-C15

Hydrocarbons are formed with very high selectivity. Furthermore arise in the process with good

Selectivity C2-C4 Hydrocarbons, which can be used as valuable raw materials in the chemical industry. In the process, a high conversion of CO2 is already achieved without recycling of excess carbon dioxide. In another aspect, the invention relates to the catalysts as such.

State of the art

The world's declining fossil reserves

Carbon carriers as well as the increasing enrichment of the atmosphere with carbon dioxide (CO2) and the resulting greenhouse effect (global warming) call for a rethinking of the use of fossil carbon as an energy carrier and source material for the production of fuels.

Currently, there is a shift in fuel production from petroleum to natural gas based processes. These are the

Synthesis gas production from methane and the catalyzed Fischer-Tropsch synthesis (FT) coupled.

Fischer-Tropsch synthesis:

CO + 2H ₂ -> [-CH ₂ -] + H ₂ O (1) As products, shorter-chain (gasoline, diesel) and longer-chain hydrocarbons (waxes) can be obtained. Gasoline contains hydrocarbons from 5 to 12

Carbon atoms, while diesel longer chain

Contains hydrocarbons, namely from about 9

Carbon atoms.

FT synthesis itself contributes to CO 2 emission since CO 2 is a by-product of several equilibrium reactions, for example, carbon monoxide and water vapor in water gas shift:

CO + H ₂ 0 C0 ₂ + H ₂ (2)

Therefore, we are looking for processes for fuel production that are C0 ₂ neutral. For example, CO2 is suitable here as the carbon source, since CO _{2 is} consumed in the production and only the previously bound amount CO _{2 is} released when the recovered fuel is combusted.

One approach is to convert C0 ₂ to CO and water with hydrogen in reverse water-gas shift (RWGS):

C0 ₂ + H ₂ CO + H ₂ 0 (3) and then convert the recovered CO in the Fischer-Tropsch reaction by hydrogenation in hydrocarbons. The overall response is then:

C0 ₂ + 3 H ₂ [-CH ₂ -] + 2 H ₂ 0 (4)

The RWGS or their reverse reaction is a

Equilibrium reaction, which is limited by the temperature and the ratio of the partial pressures. An H ₂ : C0 ₂ ratio of 3 corresponds to the stoichiometric ratio of the overall reaction, see equation (4). The CO2 conversion and the yield of CO increases with temperature; only at about 500 ° C 50% of C0 _{2 are converted} to CO and for complete conversion temperatures of well over 1000 ° C are required. In the temperature range of 220-300 ° C, the proportion of CO converted to CO2 is 12-22%.

In addition to fuel production, the largest consumer of fossil carbon carriers in the chemical industry is polymer production. Here, predominantly short-chain olefins (ethylene, propylene, butenes) are used as starting materials, from which, directly or after modification, polymers, such as

Polyethylene, polypropylene, polyacrylates and polyurethanes. At present, the olefins mentioned are produced mainly from fossil raw materials in refineries by steaming. Other methods, like the

Catalytic dehydrogenation of alkanes or the conversion of olefins into other olefins by metathesis play only a minor role and are also based on fossil fuels. In order to become independent of fossil fuels, it is desirable to use hydrocarbons for the

Produce fuel production and short-chain olefins from the raw material CO2.

Another approach, the accumulation of CO2 in the

To reduce the atmosphere and the resulting greenhouse effect (global warming), CO2 must be stored in underground caverns. However, the CO2 could react with the rock and endanger the stability of the caverns.

It would be desirable to convert the CO2 to liquid hydrocarbons (more than 5 carbon atoms), which are then stored in the caverns and can be used as needed as fuel or raw material resource for the chemical industry.

In an early work by GD Weatherbee et al. (J. Catal. 87 (1984) 352), the hydrogenation of CO2 by cobalt, Iron and ruthenium described, these were supported on silica. In D.Li et al., Appl. Catal. A 180 (1999) 227 investigated the methane production from CO2 and H ₂ in the presence of ruthenium on a Ti0 _{2 support} .

Various publications by T. Riedel et al. and H. Schulz et al. (T. Riedel, Dissertation Universität Karlsruhe 2002, H. Schulz et al., Ap l Catal A, 186 (1999) 215, T. Riedel et al., Appl. Catal. A, 186 (1999) 201; Riedel et al., Ind. Eng. Chem. Res., 40 (2001) 1355; H. Schulz et al., Topics Catal., 32 (2005) 117)

Hydrogenation of C0 ₂ by Fe / Al2C> 3 catalysts containing the promoters copper and potassium. Further, in T. Riedel et al., Appl. Catal. A, 186 (1999) 201 described in addition to the iron catalysts on AI2O3 carriers and those on Ti0 ₂ - or Si0 ₂ carriers for the hydrogenation of C0 ₂ described. In G. Kishan et al. , Catal. Lett. 56 (1998) 215, Fe-K on Al ₂ C> 3, MgO or Al ₂ O 3-MgO, with different proportions of Al ₂ O 3 and MgO, was used in the hydrogenation of CO ₂ .

Iron catalysts which can contain cerium as a promoter were described in S.-S. Nam et al. , J. Chem. Res. (1999) 344 and S.- S. Nam et al. , Appl. Catal. A 179 (1999) 155

Applied alkali metal ion-exchanged zeolites and tested in the hydrogenation of C0 ₂ . A paper by RW Dorner et al. (RW Dorner et al., "Effects of Loading and doping on Iron-based C0 ₂ Hydrogenation Catalysts", Naval Research Laboratory, NRL / MR / 6180--09-9200 (2009)) deals with the CO2 hydrogenation in the presence Yan-Al2O3-supported iron catalysts which may be doped with manganese The catalyst 100Fe6, 6Cul5, 7A14K was described in S.R. Yan et al., Appl. Catal. A 194-195 (2000) 63-70 its activity in the hydrogenation of CO2 tested.

The not very extensive literature in the field of catalytic C0 ₂ hydrogenation is described in PSS Prasad et al. , Catal. Surv. Asia 12 (2008) 170 summarized. The object of the invention is a process for producing hydrocarbons and a catalyst therefor

to provide a high selectivity for

Hydrocarbons, in particular the chain lengths C5-C15 but also the chain lengths C2-C4 at the highest possible conversion of C0 ₂ already without recycling of excess CO2 is achieved. In particular, a method is sought with which a higher selectivity for liquid C5-C15

Hydrocarbons, for example, are suitable as fuels, and a higher CC> 2 conversion than with the

Catalysts of the prior art, for example the 100Fe6, 6Cul5, 7A14K from S.-R. Yan et al. in Appl. Catal. A 194-195 (2000) 63-70.

Summary of the invention

The object is achieved by a process for the preparation of hydrocarbons from carbon dioxide and hydrogen in the presence of a specific catalyst, as defined in the appended claim 1. The used in the process according to the invention

Catalyst contains iron and at least one alkali metal and further satisfies at least one of the following features (i) to (iii):

(i) the catalyst contains, based on the

Total weight of the catalyst, iron in an amount of at least 10% by weight, preferably from 15 to 35% by weight, and further copper and at least one other selected from magnesium, zinc, lanthanum and zirconium;

(ii) the catalyst comprises TiO ₂ and / or a

Aluminum magnesium hydroxycarbonate as catalyst support;

(iii) the catalyst further contains ruthenium and / or cobalt.

A specific embodiment of the above catalyst having the feature (i) is the subject of the attached

Claim 13. Advantageous developments of the process according to the invention for the production of hydrocarbons from carbon dioxide and hydrogen and the catalyst according to the invention are

Subject of the dependent claims.

Detailed description of the invention

In the catalyst according to the invention and in the catalyst of the process according to the invention, the metals such as iron, alkali metal (eg lithium, sodium and potassium), copper, magnesium, zinc, lanthanum, aluminum, zirconium, manganese, ruthenium and cobalt can also be used as compounds, in particular as Oxides are present. Preferably, at least a portion of the metals, more preferably all metals are present as an oxide.

In the inventive method for the preparation of

Hydrocarbons of carbon dioxide and hydrogen, wherein the carbon dioxide is reacted with hydrogen in the presence of a catalyst, wherein the catalyst contains iron and at least one alkali metal.

The at least one alkali metal is advantageously selected from the group consisting of lithium, sodium, potassium and rubidium. Preferably, the catalyst contains potassium as the at least one alkali metal. Preferably, the proportion of the at least one alkali metal is 1-30 wt .-% and particularly preferably 5-12 wt .-% with respect to the iron content in

Catalyst. When the catalyst in the inventive

Contains potassium, the potassium content is preferably 1 to 30 wt .-% and particularly preferably 5 to 12 wt .-% with respect to the iron content in the catalyst.

In the process according to the invention it is essential that the

Catalyst of at least one of the following features (i) to (iii): (I) the catalyst contains, based on the total weight of the catalyst, iron in an amount of at least 10 wt .-%, preferably from 15 and 35 wt .-%, and further copper and at least one further representative selected from magnesium, zinc , Lanthanum and zirconium;

(ii) the catalyst comprises 1O2 and / or a

Aluminum magnesium hydroxycarbonate as catalyst support;

(iii) the catalyst further contains ruthenium and / or cobalt.

An embodiment of the method according to the invention

relates to the use of a catalyst satisfying feature (i) (method (i)).

Preferably, the at least one alkali metal contained in the catalyst of process (i) is potassium.

Optionally, the catalyst of process (i) may be two further representatives selected from magnesium, zinc, lanthanum and

Zirconium, included. The catalyst of process (i) may also contain manganese and / or aluminum. For example, the catalyst of process (i) may include manganese and copper. In preferred embodiments of the

According to the invention, the catalyst contains:

- potassium and lanthanum;

- potassium and magnesium;

- potassium and zirconium;

- potassium and zinc;

- potassium, magnesium and manganese; or

Potassium, zirconium and manganese, and particularly preferred are:

Potassium, magnesium and manganese; or - Potassium, zirconium and manganese.

The components potassium, copper, magnesium, zinc, lanthanum, zirconium, manganese and aluminum are promoters. For the purposes of the present application, a promoter is defined as a constituent or component of a catalyst which positively influences the catalytic reaction.

The weight ratio of iron to the total weight of all promoters in the catalyst of process (i) is preferably between 1.5 and 15.

Preferably, the catalyst of process (i) additionally contains ruthenium. The components iron and ruthenium are active components. For the purposes of the present application, an active component is defined as the catalytically active ingredient or component.

The catalyst of process (i) can be a

Include catalyst support on which the active components and promoters are applied (supported catalyst).

If the catalyst of the process (i) no

Catalyst support comprises (unsupported catalyst), the total weight of all promoters in the catalyst based on the catalyst as a whole preferably between 15 and 50 wt .-% and particularly preferably between 30 and 40 wt .-%. Particularly preferred examples of the unsupported catalyst of process (i) are:

11, 3Lal4, 1CU70, 7Fe3, 9K; and

11, 6Mgll, 6Mnll, 6Cu58, 2Fe7, OK,

wherein the metals may be present as oxide and the proportions of the metals in wt .-%, based on the total weight of all metals in metallic form in the catalyst are given. Preferably, at least a portion of the metals, more preferably all metals are present as an oxide. When the catalyst of process (i) is supported, the catalyst support may be selected from the group consisting of Al 2 O 3, Al 2 O 3 MgO, TiC> 2, La 2 O 3, ZrC> 2, ZrC> 2 La 2 C> 3, ZrO 2, SiO 2, zeolites and aluminum -Magnesiumhydroxycarbonaten be selected. AI2O3-MgO refers to mixtures of Al2O3 and MgO, the

Mixing ratio can be arbitrary. ZrC> 2-1 ^ 203 refers to mixtures of ZrÜ2 and La2Ü3, wherein the mixing ratio can be arbitrary, preferably the weight ratio of La ₂ 0 ₃ : Zr0 _{2 is} between 5:95 and 15:85. Zr0 ₂ -Si0 ₂ denotes mixtures of ZrC> 2 and S1O2, where the

Mixing ratio can be arbitrary. In the aluminum magnesium hydroxycarbonates, the weight ratio between Al 2 O 3 and MgO may be arbitrary. Preferably, the weight ratio of Al 2 O 3: MgO is between 30:70 (e.g., Pural MG70) and 50:50.

Magnesium hydroxycarbonates include amorphous and crystalline forms, among the crystalline forms is hydrotalcite

prefers .

Preferred catalyst supports are 102, Al 2 O 3 and aluminum magnesium hydroxycarbonate, with T1O 2 being particularly preferred. The support materials Al2O3 and T1O2 are advantageous in terms of the yield of C5-C15 hydrocarbons. If 1O2 is used as catalyst support in the catalyst of process (i), a high yield of C5-C15

Hydrocarbons achieved while at the same time little

Methane is formed. The catalyst support preferably has a particle size of 100 to 250 pm.

The total weight of all promoters in the catalyst of

Process (i) is preferably between 1.5 and 20

Wt .-% and particularly preferably between 3 and 10 wt .-% based on the weight of the catalyst as a whole.

The supported catalyst of process (i) is

preferably selected from the following catalysts: 0.07RuI, 27MgI, 78Cu 20Fe 1.74K / Al ₂ O ₃ ;

0, lRu 0.26Mg 20Fe 2, 1K / A1 ₂ 0 ₃ ;

0.08Ru 0.95Mg 2.49Cu 20Fe 1.52K / A1 ₂ 0 ₃ ;

0.17Ru l, 15Mg 2.76Cu 20Fe 1.82K / A1 ₂ 0 ₃ ;

0.17RuI, 15Mg 2.19Cu 20Fe 1.52K / Al ₂ O ₃ ;

0.02Ru l, 02Mg 0, lZr 20Fe 0.83K / A1 ₂ 0 ₃ ;

0.63La 4Cu 20Fe 1.31K / Al ₂ 0 ₃ ;

0.07Ru 0.3Zn 20Fe 2, 1K / TiO ₂ ;

2.23Zr 4Cu 20Fe 1.73K / Ti0 ₂ ;

0, 1Ru 0.2Cu 0.29Zn 20Fe 1.4K / Ti0 ₂ ;

1.01 Cu 20 Fe 1.7K / Ti0 ₂ ;

2.3Zr l, 8Mn 2.6Zn 20Fe 1.7K / Ti0 ₂ ;

3.27Zr 2.96Mn 1Cu 20Fe 1.48K / Ti0 ₂ ;

20Fe 2.66A1 2.14Cu 1.78K / TiO ₂ ;

3.18La 4Cu 20Fe 1.1K / TiO ₂ ;

20Fe l, 78Cu 1.74K l, 27Mg 0.07Ru / aluminum magnesium hydroxycarbonate;

20Fe 4Mg 4Mn 4Cu 2.4K / aluminum magnesium hydroxycarbonate; and

20Fe 2.1K 0.3Zn 0.07Ru / aluminum-magnesium hydroxycarbonate, the metals may be present as oxide and the proportions of the metals in wt .-%, based on the sum of

Total weight of all metals in metallic form in

Catalyst and the catalyst support are specified.

Preferably, at least a portion of the metals, more preferably all metals are present as an oxide.

Another embodiment of the process according to the invention relates to the use of a catalyst which satisfies feature (ii) (process (ii)). If Ti0 ₂ or aluminum magnesium hydroxycarbonates are used as catalyst carriers in the catalyst of the process according to the invention, a particularly high yield of valuable metal is obtained

Hydrocarbons, such as C ₂ -C 4 and C 5 -C 15 hydrocarbons, achieved while at the same time little undesirable methane is formed. The catalyst supports TiC> 2 and aluminum magnesium hydroxycarbonates preferably have a particle size of 100 to 250 pm.

The proportion of iron in the catalyst, based on the

Total catalyst, is preferably between 10 and 50 wt .-% iron, more preferably between 15 and 35 wt .-% iron and most preferably between 20 and 25 wt .-% iron. Due to this high iron content, a particularly high CC> 2 conversion is achieved.

Preferably, the catalyst in process (ii) contains potassium as the at least one alkali metal. In a preferred embodiment of process (ii), the catalyst comprises at least one further member selected from the group consisting of magnesium, zinc, lanthanum, aluminum, zirconium, manganese and copper. Optionally, two, three or four further representatives may be included in the catalyst of process (ii). Preferably, the at least one further representative is magnesium, zinc or copper. Particularly preferably, the catalyst in process (ii) contains potassium and copper and at least one further representative selected from the group consisting of aluminum,

Lanthanum, zirconium, zinc and magnesium. In preferred

Embodiments of process (ii) include

Catalyst:

- potassium and zinc;

- potassium and magnesium;

- potassium and copper;

- potassium, copper and zirconium;

- potassium, copper and zinc;

- potassium, copper and aluminum;

- potassium, copper and lanthanum;

- Potassium, copper, magnesium and manganese;

- potassium, zirconium, manganese and zinc; or

- potassium, copper, zirconium and manganese, And particularly preferred are:

- potassium, zirconium, manganese and zinc; or

- Potassium, copper, zirconium and manganese.

The components potassium, copper, magnesium, zinc, lanthanum, zirconium, manganese and aluminum are promoters.

The weight ratio of iron to the total weight of all promoters in the catalyst of process (ii) is

preferably between 1.5 and 15.

The total weight of all promoters in the catalyst of

Process (ii) is preferably between 1.5 and 20% by weight and more preferably between 3 and 10% by weight, based on the weight of the catalyst as a whole.

Preferably, the catalyst of process (ii) additionally contains ruthenium. The components iron and ruthenium are active components.

Examples of the catalysts of process (ii) are:

0.07Ru 0.3Zn 20Fe 2, 1K / TiO ₂ ;

0.2Ru 20Fe 1.99K / Ti0 ₂ ;

0.2Ru 20Fe 1.52K / TiO ₂ ;

2.23Zr 4Cu 20Fe 1.73K / Ti0 ₂ ;

0, 1Ru 0.2Cu 0.29Zn 20Fe 1.4K / Ti0 ₂ ;

1, 01Cu 20Fe 1.7K / TiO ₂ ;

2.3Zr l, 8Mn 2.6Zn 20Fe 1.7K / Ti0 ₂ ;

0.2Ru 20Fe 0.98K / TiO ₂ ;

3.27Zr 2.96Mn ICu 20Fe 1.48K / Ti0 ₂ ;

0.2Ru 20Fe 1.16K / TiO ₂ ;

20Fe 2.66A1 2.14Cu 1.78K / TiO ₂ ; and

3.18La 4Cu 20Fe 1.1K / TiO ₂ ,

wherein the metals may be present as oxide and the proportions of the metals in wt .-%, based on the sum of Total weight of all metals in metallic form in

Catalyst and the catalyst support are specified.

A further embodiment of the process according to the invention relates to the use of a catalyst which satisfies feature (iii) (process (iii)). In this embodiment, the components are iron, ruthenium and cobalt

Active components.

Preferably, the catalyst of process (iii) contains potassium as the at least one alkali metal. In a

In a preferred embodiment of process (iii), the catalyst contains at least one further representative, this being selected from the group consisting of magnesium, zinc, lanthanum,

Aluminum, zirconium, manganese and copper is selected.

Optionally, two, three or four further representatives may be included in the catalyst of process (iii). Preferably, the at least one further representative is magnesium, zinc or copper. More preferably, the catalyst in process (iii) contains potassium and copper and at least one further member selected from the group

consisting of aluminum, lanthanum, zirconium, zinc and

Magnesium. In particularly preferred embodiments of process (iii), the catalyst comprises:

Potassium and zinc;

Potassium and magnesium;

Potassium and copper;

Potassium, zirconium, manganese and zinc;

Potassium, copper, magnesium and manganese;

Potassium, copper, zirconium and manganese.

The components potassium, copper, magnesium, zinc, lanthanum, zirconium, manganese and aluminum are promoters. The weight ratio of iron to the total weight of all promoters in the catalyst of process (iii) is

preferably between 1.5 and 15.

The catalyst in process (iii) may be both supported and unsupported.

If the catalyst of process (iii) is an unsupported one, the total weight of all promoters in the catalyst relative to the catalyst as a whole is preferably between 15 and 50% by weight and more preferably between 30 and 40% by weight.

When the catalyst of process (iii) is supported - this is a preferred embodiment - the catalyst support may be selected from the group consisting of Al ₂ O ₃ , Al ₂ O ₃ MgO, TiO ₂ , La ₂ O ₃ , ZrO ₂ , ZrO ₂ La 20 ₃ , Zr0 ₂ -Si0 ₂ , zeolites and aluminum magnesium hydroxycarbonates be selected. AI2O3-MgO refers to mixtures of Al2O3 and MgO, the

Mixing ratio can be arbitrary. r02-La2Ü3 denotes mixtures of ZrC> 2 and L .203, wherein the mixing ratio can be arbitrary, preferably the weight ratio of La ₂ 0 ₃ : Zr0 _{2 is} between 5:95 and 15:85. Zr0 ₂ -Si0 ₂ denotes mixtures of Zr02 and SXO2, where the

Mixing ratio can be arbitrary. In the aluminum magnesium hydroxycarbonates, the weight ratio

between AI2O3 and MgO be arbitrary. Preferably, the weight ratio of Al 2 O 3: MgO is between 30:70 (e.g., Pural MG70) and 50:50.

prefers .

Preferred catalyst supports are iO 2, Al 2 O 3 and aluminum magnesium hydroxycarbonate, with 10O 2 being particularly preferred. These support materials are with regard to the yield of C5- C _] _5 hydrocarbons advantageous. The catalyst support preferably has a particle size of 100 to 250 μπι.

The total weight of all promoters in the catalyst of

Process (iii) is preferably between 1.5 and 20% by weight and more preferably between 3 and 10% by weight, based on the weight of the catalyst as a whole.

In process (iii) the following catalyst is particularly preferred:

0.2Ru 18.08Fe 2.17K l, 92Co / Al ₂ 0 ₃ , where the metals can be present as oxide and the proportions of the metals in% by weight, based on the sum of

Total weight of all metals in metallic form in

Catalyst and the catalyst support are specified.

A further embodiment of the process according to the invention (process (iv)) relates to the preparation of

Hydrocarbons of carbon dioxide and hydrogen, wherein the carbon dioxide is reacted with hydrogen in the presence of a catalyst, wherein the catalyst contains iron, potassium, copper and magnesium, wherein iron in an amount of

at least 8 wt .-%, preferably between 10 and 50 wt .-%, particularly preferably between 15 and 35 wt .-%, based on the total weight of the catalyst is included. Of the

Catalyst may also contain manganese. Preferably, the proportion of potassium is 1-30 wt .-% and particularly preferably 5-12 wt .-% with respect to the iron content in the catalyst. The components potassium, copper, magnesium, and manganese are promoters. Iron is an active component

contain. The weight ratio of iron to the total weight of all promoters in the catalyst of the process is preferably between 1.5 and 15.

The catalyst of the process may comprise a catalyst support on which the active components and promoters

are applied (supported catalyst).

If the catalyst of the process does not comprise a catalyst support (unsupported catalyst), the total weight of all promoters in the catalyst based on the catalyst as a whole is preferably between 15 and 50% by weight and

particularly preferably between 30 and 40 wt .-%.

If the catalyst of the process is supported, the catalyst support can be selected from the group consisting of Al 2 O 3, Al 2 O 3 -MgO, TiC> 2, I 2 O 3, ZrC> 2, ZrC 1 -Cl 2, ZrO 2-SiC> 2, zeolites and Aluminum magnesium hydroxycarbonates be selected. AI2O3-MgO refers to mixtures of Al2O3 and MgO, the

Mixing ratio can be arbitrary. Zr02-La2Ü3 denotes mixtures of ZrC> 2 and L .203, wherein the mixing ratio can be arbitrary, preferably the weight ratio of La2Ü3: ZrC> 2 is between 5:95 and 15:85. Zr0 ₂ -SiC> 2 denotes mixtures of ZrC > 2 and S1O2, where the

prefers .

The catalyst support is preferably Al 2 O 3. Of the

Catalyst support preferably has a particle size of 100 to 250] i. The total weight of all promoters in the catalyst of

Method is preferably between 1.5 and 20 wt .-% and particularly preferably between 3 and 10 wt .-% based on the weight of the catalyst as a whole.

The following catalysts are particularly preferred: 10El, 0Mg 2.0Cu 0.8K / A1 ₂ 0 ₃

lOfe 2.0Mg 2.0Mn 2.0Cu 1.2K / Al ₂ 0 ₃ where the metals can be present as oxide and the proportions of the metals in% by weight, based on the sum of

Total weight of all metals in metallic form in

Catalyst and the catalyst support are specified.

Another aspect of the invention relates to the use of the catalysts as described above in the process according to the invention, as described, for example, in the attached US Pat

Claim 1 is defined.

In the following, the method according to the invention is generally described. The process of the invention relates to the reaction of carbon dioxide with hydrogen in the presence of a catalyst, i. the hydrogenation of carbon dioxide by hydrogen in the presence of a catalyst

Hydrocarbons. Preferably, the RWGS reaction of carbon dioxide to carbon monoxide takes place and the carbon monoxide formed is converted to hydrocarbons in a Fischer-Tropsch synthesis. Thus, the process of the invention may also be referred to generally as a Fischer-Tropsch process. Preferred are the

Hydrocarbons C5-C15 hydrocarbons and / or C2-C4 hydrocarbons. The reaction of the carbon dioxide with hydrogen in the process of the invention preferably takes place at a temperature of 150 to 400 ° C, more preferably 300 to 370 ° C, even more preferably 320 ° C to 370 ° C and most preferably 350 ° C , A temperature of 150 to 400 ° C leads to a particularly high yield

Hydrocarbons, especially C5-C15 hydrocarbons. A temperature of 300 ° C to 350 ° C is particularly suitable in relation to the yield of C5-C15 hydrocarbons. In a preferred embodiment of the invention

Procedure finds the implementation of carbon dioxide

Hydrogen at a pressure of 10 to 50 bar and more preferably between 15 to 30 bar instead. Preferably, the reaction of the carbon dioxide is carried out with hydrogen at a temperature of 300 ° C and a pressure of 15 bar or at a temperature of 350 ° C and a pressure of 10 bar.

In a preferred embodiment of the method according to the invention, the molar ratio of the used

Hydrogen to carbon dioxide 4 to 8 and preferably 6.

The carbon dioxide used in the process according to the invention can be obtained by flue gas separation from the exhaust gas of power plants, which preferably generate electrical energy from fossil fuels. The hydrogen gas used in the process according to the invention can by

Be obtained electrolysis, which are preferably powered by electricity from photovoltaic, wind turbines or other CO2-neutral systems.

The inventive method for the preparation of

Hydrocarbons from carbon dioxide and hydrogen can be carried out in a fixed bed, fluidized bed or bubble column reactor. Examples of suitable fixed bed reactors are gas-flow fixed bed catalytic reactors,

Bubble column reactors and tube bundle reactors. in the A gas-flow catalytic fixed bed reactor according to the invention is preferably used.

In the reaction of carbon dioxide and hydrogen in the process according to the invention, a product mixture is obtained, the hydrocarbons, unreacted

Hydrogen, water, unreacted carbon dioxide, and carbon monoxide may contain. The carbon monoxide is

intermediately formed from carbon dioxide and hydrogen in the RWGS. Preferably, the product mixture contains C5-C15 and C2-C hydrocarbons. Contain the C2-C4

Hydrocarbons C2-C alkanes, so they can be dehydrogenated after their separation to C2-C alkenes, especially ethylene, propylene and butenes. ^c 5 ^c ~ 15 hydrocarbons include linear, branched and cyclic alkanes and alkenes with a chain length of 5 to 15 carbon atoms. Examples of the C5-C15 alkanes are linear, branched and cyclic isomers of pentanes, hexanes, heptanes, octanes, nonanes, decanes, undecans, dodecanes, tridecanes, tetradecanes and pentadecanes.

Examples of the 05-015 alkenes include linear, branched and cyclic isomers of pentenes, hexenes, heptenes, octenes, nonenes, decenes, undecenes, dodecenes, tridecenes,

Tetradecenes and pentadecenes. The C5-C15 hydrocarbons are preferably linear and / or branched alkanes and alkenes.

C2-C4 hydrocarbons include C2-C4 alkanes and C2-C4 alkenes containing from 2 to 4 carbon atoms, where the C4 alkanes and C4 alkenes can be both linear and branched. Examples of the C 2 -C 4 hydrocarbons are ethane, ethylene, propane, propylene, n-butane, isobutane, 1-butene, 2-butene and 2-methyl-1-propene. Butenes include n-butane, isobutane, 1-butene, 2-butene and 2-methyl-1-propene. With the method according to the invention, it is possible to use CO2 predominantly the valuable C2-C15 hydrocarbons

manufacture. Accordingly, in the process according to the invention, the hydrocarbons produced are preferably predominantly ^C 2 ^-C 15 hydrocarbons, ie those produced

Hydrocarbons include C2-C15 hydrocarbons in an amount of at least 50 mol%. In other words, the hydrocarbons of the product mixture obtained in the process according to the invention are preferably ≥50 mol%, more preferably ≥70 mol% of C2-C15 hydrocarbons, based on the hydrocarbons produced.

With the method according to the invention it is possible, in particular, a larger molar fraction of C5-C15

Hydrocarbons (which are useful, for example, as fuels such as gasoline, diesel and kerosene) as of C2-C hydrocarbons (which may be after dehydration as

Starting materials for the chemical industry)

receive. In other words, the molar ratio of ^c is 5 ~ 15 ^c hydrocarbons to C2-C4 hydrocarbons in the product mixture preferably>. 1

As by-products in the process according to the invention methane and higher hydrocarbons (with more than 16

Carbon atoms), in particular waxes. These

By-products can be used in the usual way.

For example, the methane produced in the

process according to the invention for heating purposes.

The product gas is preferably cooled in a phase separator to 35 ° C, thereby to deposit water in liquid form. If necessary, excess carbon dioxide can be removed from the product gas by absorption in a further step. For this purpose, the product gas can be passed through a medium, for example a solvent, which

Absorbs carbon dioxide. Alternatively, the carbon dioxide by pressure swing adsorption (PSA adsorption) or by means of a membrane are removed from the product gas. The separated carbon dioxide gas may include the educt gas stream comprising hydrogen gas and carbon dioxide gas in the

be fed to the invention.

The product gas can be separated in a cryogenic separation apparatus or by cryogenic separation technique into those components which are liquid or gaseous at room temperature (20 ° C), with a cryogenic heat exchanger being preferred. As liquids, the C5-C15

Hydrocarbons are obtained while the C2-C4

Hydrocarbons, methane, excess carbon monoxide and hydrogen are obtained in gaseous form.

Optionally, excess hydrogen gas can be recycled by removing methane from the gas mixture of methane, excess carbon monoxide, and hydrogen by means of membrane separation technology or cryogenic separation. The recycled hydrogen gas can then be recycled to the educt gas stream of the process according to the invention

be supplied.

In a preferred embodiment of the process according to the invention, the catalyst is reduced with hydrogen before use in the process according to the invention. For this purpose, the catalyst is, for example, at 500 ° C in a

Inert gas stream (e.g., nitrogen) containing hydrogen.

The catalyst used in the process of the present invention can be prepared by precipitation from metal salt solutions or by milling metal oxides. This gives an unsupported catalyst. One

supported catalyst can be prepared by reacting a catalyst support with metal salt solutions, e.g. aqueous metal nitrate solutions, impregnated, for example

impregnated with water. It is preferably with the Solution started, which has the highest concentration (eg in g / 1). Preferably, the impregnated catalyst support is dried after each impregnation step. Preferably, the catalysts become oxalate during production

added, wherein the oxalate is preferably in the form of

Ammonium oxalate or metal oxalate is added. Particularly preferred is ammonium oxalate. As has been shown, this leads to a better distribution of the active components, in particular iron, and the promoters in the catalyst or on the support.

The precipitated or ground metal salts and the

impregnated catalyst supports are preferably calcined after drying. Calcination may be carried out, for example, in a muffle furnace in still air (e.g., at 350 ° C) or in the inert gas stream (e.g., at 400 ° C). When a catalyst containing oxalate is calcined, complete decomposition (combustion) of the oxalate occurs; the oxalate is removed without residue during calcination.

According to a further aspect, the invention relates to the

Catalyst as such. The term "catalyst"

illustrates that it is a composition or compound that is suitable as a catalyst,

in particular in the method according to the invention for

Production of hydrocarbons.

The catalyst according to the invention comprises as

Catalyst components, based on the total weight of the catalyst, at least 10 wt .-%, preferably 10-50 wt .-%, particularly preferably 15 and 35 wt .-% and very particularly preferably 20-25 wt .-% iron, and potassium, Copper and at least one other component selected from magnesium, zinc, lanthanum and zirconium. In addition, the

catalyst according to the invention at least one of the following metals: manganese, ruthenium, aluminum and cobalt. Preferred embodiments of the catalyst according to the invention contain

- iron, potassium, copper and lanthanum;

- iron, potassium, copper and zirconium;

- iron, potassium, copper, magnesium and manganese;

- iron, potassium, copper, zirconium and manganese;

- iron, ruthenium, potassium, copper and magnesium; or

- iron, ruthenium, potassium, copper and zinc.

The components iron and ruthenium are active components.

The weight ratio of iron to the total weight of all metals (promoters) from the group potassium, copper,

Magnesium, zinc, lanthanum, aluminum, zirconium and manganese in the catalyst according to the invention is preferably between 1.5 and 15. Preferably, at least some of the metals are present, more preferably all metals are present as oxide.

The catalyst according to the invention can be both supported and unsupported.

If the catalyst of the invention is an unsupported, the total weight of all metals selected from the group consisting of potassium, copper, magnesium, zinc, lanthanum, aluminum, zirconium and manganese in the catalyst based on the total catalyst is preferably between 15 and 50 wt .-% and especially

preferably between 30 and 40 wt .-%. Particularly preferred examples of the unsupported catalyst of the invention are: H, 3Lal4, 1Cu70.7 Fe3.9K; and

11, 6Mgll, 6Mnll, 6Cu58, 2Fe7, OK,

wherein the metals may be present as oxide and the proportions of the metals in wt .-%, based on the total weight of all metals in metallic form in the catalyst are given. Preferably, at least a portion of the metals, more preferably all metals are present as an oxide. When the catalyst of the present invention is supported, the support may be selected from the group consisting of Al ₂ O ₃ , Al ₂ O ₃ MgO, TiO ₂ , La ₂ O ₃ , ZrO ₂ , ZrO ₂ -LaO _{3 /} ZrO ₂ -SiO ₂ , zeolites and aluminum magnesium hydroxycarbonates be. AI2O3-MgO refers to mixtures of Al2O3 and MgO, the

Mixing ratio can be arbitrary. Zr02-La2Ü3 denotes mixtures of ZrC> 2 and La2Ü3, wherein the mixing ratio can be arbitrary, preferably the weight ratio of La ₂ 0 ₃ : ZrC> 2 is between 5:95 and 15:85. Zr0 ₂ -Si0 ₂ denotes mixtures of ZrO 2 and S1O2, where the

prefers .

Preferred catalyst supports are TiO 2 _; AI2O3 and aluminum magnesium hydroxycarbonate. These support materials are advantageous in terms of the yield of C5-C15 hydrocarbons. Contains the catalyst T1O2 as a carrier, so is a high yield of C5-C15 hydrocarbons in the

Implementation of carbon dioxide with hydrogen in the presence of the catalyst achieved while at the same time little methane is formed.

The total weight of all metals from the group potassium,

Copper, magnesium, zinc, lanthanum, aluminum, zirconium and manganese in the supported catalyst is preferably between 1.5 and 20 wt .-% and particularly preferably between 3 and 10 wt .-% based on the weight of the catalyst as a whole. The supported catalyst of the invention is preferably selected from the following catalysts:

0.07RuI, 27MgI, 78Cu 20Fe 1.74K / A1 ₂ 0 ₃ ;

0.08Ru 0.91Mg 2.39Cu 19.23Fe 1.46K / Al ₂ 0 ₃ ;

0.16Ru l, llMg 2.66Cu 19.26Fe 1.75K / A1 ₂ 0 ₃ ;

0.16Ru l, llMg 2, llCu 19.23 Fe 1.46 K / Al ₂ O ₃ ;

20Fe 2.66A1 2.14Cu 1.78K / TiO ₂ ;

3.18La 4Cu 20Fe 1.1K / TiO ₂ ;

0.63La 4Cu 20Fe 1.31K / Al ₂ 0 ₃ ;

2.23Zr 4Cu 20Fe 1.73K / Ti0 ₂ ;

0, 1Ru 0.2Cu 0.29Zn 20Fe 1.4K / Ti0 ₂ ;

3.27Zr 2.96Mn 1Cu 20Fe 1.48K / Ti0 ₂ ;

20Fe l, 78Cu 1.74K l, 27Mg 0.07Ru / aluminum

Magnesiumhydrox carbonate; and

20Fe 4Mg 4Mn 4Cu 2.4K / aluminum magnesium hydroxycarbonate, the metals may be present as oxide and the proportions of the metals in wt .-%, based on the sum of

Total weight of all metals in metallic form in

Catalyst and the carrier are specified. Preferably, at least a portion of the metals, more preferably all metals are present as an oxide.

Another aspect of the invention relates to the use of the catalysts, as described above, in one of

Process (i) to (iv) according to the invention.

As is customary, in the cited catalysts the part following the symbol "/" denotes the support All components before "/" represent the active components and promoters, which may be present at least partially in oxidic form. For example, 0.07Ru 0.3Zn 20Fe 1.1K / TiO _{2 means} that the catalyst is TiO ₂ as carrier, as well as 0.07 wt% Ru, 0.3 wt% Zn, 20 wt% Fe and 1.1 wt .-% K, all based on the sum of the total weight of all metals in metallic form in the catalyst and the catalyst support contains. In the following examples are given which illustrate the invention in more detail, but are not intended to limit.

Examples

Catalyst 1: II, 3La 14, ICu 70.7Fe 3, 9K

0.71 g of La (NO ₃ ) ₃ '6H ₂ O, 1.07 g of Cu (NO ₃ ) ₂ ' 3H ₂ O, 9.49 g

Fe (NO ₃ ) 3'9H ₂ O and 0.20 g of KNO ₃ were dissolved in 100 ml of dist. Dissolved water and heated to 90 ° C. To the warm solution, a 25% NH 4 solution was added dropwise until no further precipitation was observed. Subsequently, the

Mixture slowly evaporated to dryness, in

Drying oven dried at 130 ° C and calcined in a muffle furnace at 350 ° C in air for 5 hours.

Catalyst 2: II, 6Mg II, 6Mn II, 6Cu 58.2Fe 7, OK

Catalyst 2 was prepared analogously to the preparation of catalyst 1 from 2.45 g of Mg (NO ₃ ) ₂ '6H ₂ O, 1.06 g of Mn (NO ₃ ) ₂ .4Η ₂ 0, 0.88 g of Cu (NO ₃ ) ₂ -3H ₂ 0, 7.81 g Fe (NO ₃ ) 3 .9H ₂ 0 and 0.36 g K 0 ₃

produced .

Catalyst 3: 19.3 Fe 1.5K 0.2Ru / TiQ ₂

Step 1: 5 ml of an aqueous Fe (NO ₃ ) 3 solution (content 48.7 g / 1 Fe) were added to lg Ti0 ₂ (Degussa Aerolyst 7708, particle size 0.1-0, 25 mm) while shaking at room temperature.

pipetted, the mixture heated to 100 ° C and below

Shake at 100 ° C and dried.

Step 2: 5 ml of an aqueous KNO 3 solution (content 3.69 g / 1 K) were pipetted onto the dried mixture from step 1 with shaking at room temperature, the mixture was heated to 100 ° C. and concentrated by shaking at 100 ° C. and dried , Step 3: To the dried mixture of Step 2 was added 5 ml of an aqueous under stirring at room temperature

Pipetted Ru (NO) (NO3) 3 solution (content 0.49 g / 1 Ru), the mixture was heated to 100 ° C and concentrated by shaking at 100 ° C and dried.

Step 4: The dried mixture was calcined for 5 hours in a muffle furnace at 350 ° C in air.

Catalyst 4: 19.2 Fe 1.9K 0.2Ru / Tip _?

Catalyst 4 was prepared analogously to the preparation of catalyst 3, wherein in step 2, the content of the aqueous K O3 solution was 4.85 g / 1 K.

Catalyst 5: 0, lRu 0.2Cu 0.3Zn 19.2Fe 1.3K / TiO;

Catalyst 5 was prepared analogously to the preparation of catalyst 3, wherein in step 1, the content of the aqueous

Fe (NO 3) 3 solution was 48.8 g / 1 Fe, in step 2 the content of the aqueous K O 3 solution was 3.41 g / 1 K, in step 3 the content of the aqueous Zn (NO 3) 2 solution 0.71 g / 1 Zn, and step 4 was replaced by the following steps 4 through 6:

Step 4: To the dried mixture of step 3, shaking at room temperature 5 ml of an aqueous

Cu (NO3) 2 solution (content 0.48 g / 1 Cu) pipetted, the mixture was heated to 100 ° C and evaporated with shaking at 100 ° C and dried.

Step 5: To the dried mixture from step 4, shaking at room temperature, 5 ml of an aqueous

Pipetted Ru (NO) (NO3) 3 solution (content 0.26 g / 1 Ru), the mixture was heated to 100 ° C and concentrated by shaking at 100 ° C and dried.

Step 6: The dried mixture was calcined for 5 hours in a muffle furnace at 350 ° C in air. Catalyst 6: 0.07Ru 0.3Zn 19.2Fe 2, OK / Tip

Catalyst 6 was prepared analogously to the preparation of catalyst 3, wherein in step 1, the content of the aqueous

Fe (NO 3) 3 solution 49.0 g / 1 Fe, in step 2 the content of the aqueous KNO 3 solution was 5.13 g / 1 K, in step 3 the content of the aqueous Zn (NO 3) 2 solution was 0 , 73 g / 1 Zn, and step 4 was replaced by the following steps 4 and 5:

Ru (NO) (NO3) 3 solution (content 0.18 g / 1 Ru) pipetted

Mixture heated to 100 ° C and evaporated with shaking at 100 ° C and dried.

Step 5: The dried mixture was calcined for 5 hours in a muffle furnace at 350 ° C in air.

Catalyst 7: 2.2Zr l, 7Mn 2.4Zn 18.8Fe 1.6K / TiO _?

Catalyst 7 was prepared analogously to the preparation of catalyst 5, wherein in step 1 the content of the aqueous Fe (NO 3) 3 solution was 51.3 g / 1 Fe, in step 2 the content of the aqueous KNO 3 solution was 4.37 g / 1 K in step 3, the content of the aqueous n (NO 3) 2 solution was 6.68 g / 1 Zn, in step 4, the content of the aqueous ZrO (NO 3) 2 solution was 5.91 g / 1 Zr and in step 5, the content of the aqueous Mn (NC> 3) 2 solution was 4.62 g / 1 Mn.

Catalyst 8: 0.97Cu 19.16Fe 1.63K / Tip _?

Catalyst 8 was prepared analogously to the preparation of catalyst 3, wherein in step 1 5 ml of an aqueous solution of Fe (NC> 3) 3 (content 49.1 g / 1 Fe) and 2 ml of a

Ammonium oxalate solution (content 25.15 g / 1 oxalate) were used, in step 2 the content of the aqueous KNO3 solution was 4.17 g / 1 K and in step 3 the content of the aqueous Cu (N0 ₃ ) 2 solution 2, 48 g / 1 Cu. Catalyst 9: 2, lZr 3.8Cu 18.8Fe 1.6K / TiP

Catalyst 9 was prepared analogously to the preparation of catalyst 6, wherein in step 1 the content of the aqueous Fe (NO 3) 3 solution was 51.2 g / 1 Fe, in step 2 the content of the aqueous KNO 3 solution was 4.42 g / 1K, in Step 3, the content of the Cu (NO3) 2 aqueous solution was 10.24 g / 1Cu, and in Step 4, the content of the ZrO (NO3) 2 aqueous solution was 5.71 g / 1Zr.

Catalyst 10: 3, lZr 2, 8Mn 0.9Cu 18.8Fe 1.4K / Tip _?

Catalyst 10 was prepared analogously to the preparation of catalyst 5, wherein in step 1 the content of the aqueous Fe (NO 3) 3 solution was 51.5 g / 1 Fe, in step 2 the content of the aqueous KNC> 3 solution was 3.80 g / 1 K was, in step 3, the content of the aqueous ZrO (NO 3) 2 solution was 8.43 g / 1 Zr, in step 4, the content of the aqueous Mn (NO 3) 2 solution was 7.62 g / 1 Mn and in step 5, the content of the aqueous Cu (NC> 3) 2 solution was 2.57 g / l Cu.

Results of Catalytic Tests of Catalysts 1-10

Catalysts 1-10 were added for CO2 hydrogenation

Hydrocarbons tested. In each case, 0.3 g of a catalyst in a stainless steel reactor (5 mm

Inside diameter) installed. The catalyst was present

Start of experiment in a 10% H2 / N2 stream for 2 h at 500 ° C and 10 bar reduced and then in this gas

Reaction temperature cooled. The catalytic test was carried out under the reaction conditions mentioned in Table 1. The product mixture was analyzed by gas chromatography, and the conversion (X) and yields (Y) educt-based and the

Selectivity (S) calculated product-based.

The examination of the catalytic properties of the catalysts 1 - 10 with respect to the hydrogenation of carbon dioxide with

Hydrogen was carried out in a fixed bed reactor (stainless steel tube, Inner diameter 5 mm). All catalysts were used in a grain fraction of 100-250 μm to

Minimize mass transfer and one

Plug flow in the reactor too

guarantee .

The analysis of the product gas was carried out by an on-line coupled Gas Chromatograph in the gas phase. For this purpose, an operating pressure of 10 bar was chosen and, secondly, all the pipes and valves after the reactor and the GC inlet system were heated to at least 150 ° C. In addition, a hot gas separator (150 ° C) and a cold gas separator (room temperature), each with integrated aerosol filter, were integrated into the flue pipe. It became the two-dimensional

Capillary gas chromatography applied.

The following components were analyzed:

• By means of thermal conductivity detector (WLD): CO2, ethylene, ethane, water, H2, N2, methane, CO

• Flame ionization detector (FID): methane, C2-C (all alkane and olefin isomers), C ^ -C ^ Q (n-alkanes and n-1 olefins), the other C ^ -CIQ isomers were analyzed but not structurally assigned.

For analysis, an Agilent 7890 gas chromatograph with two independent channels was used. Both channels were operated with helium as a carrier gas. A channel of

Gas chromatographs were equipped with a PorapakQ column and a PoraPlotQ column. The columns were heated with a temperature program from the start temperature 50 ° C to 200 ° C. The second channel was equipped with a FFAP column and an Al203 / KCl column (25m x 0.32mm, 5pm film thickness) with the FFAP column operating at a temperature of 50-200 ° C. The A ^ Oß / KCl column was washed with a

Temperature program operated from 80 ° C to 200 ° C. Table 1: Results of the catalytic tests. Reaction conditions: p = 15 bar, H2: CC> 2 = 6, GHSV = 1320 ml g _R at ^{-1 h_1}

Olefin content = proportion of C2-C4 olefins in mol% based on all the C2-C4 hydrocarbons (Y (C ₂ -C ₄₎₎

Catalysts 11-67

In the synthesis robot Sophas (Zinsser Analytics), the catalysts 11-67 were prepared by impregnation of carrier materials. If several components are contained on a carrier, the impregnation became sequential,

starting with the highest concentration component, drying at a temperature of 100 ° C after each impregnation step. This was

ensured that all catalyst components were deposited on the support material.

After final drying in the synthesis robot, the catalysts were calcined in a muffle furnace for 5 h in stagnant air at 350 ° C (heating rate 5 K / min). The oxalate-containing

In contrast to this, samples were heated at only 2.5 K / min because of the otherwise too rapid oxalate decomposition.

Starting materials:

- Support materials: γ-Αΐ2θ3 (Condea), T1O2 (Degussa

Aerolyst 7708), S1O2 (Degussa Aerolyst 355), aluminum magnesium hydroxycarbonate with a weight ratio A1 ₂ 0 ₃ : MgO of 30: 70 (Pural MG70)

Table 2 summarizes the compositions of catalysts 11-67. The proportion of the respective metal in metallic form is given in wt .-% and refers to the total weight of all metals in metallic form in the catalyst and the catalyst support. Table 2: Compositions of the catalysts

*: Oxalate was used in the preparation of the catalyst, but in the composition of the calcined catalyst, oxalate is not included.

Continued Table 2: Compositions of the catalysts

Results of Catalytic Tests of Catalysts 11-67

The catalytic properties of the catalysts 11-67 with respect to the hydrogenation of carbon dioxide with hydrogen and the analysis of the product gases were tested analogously to the testing and analysis of the catalysts 1-10.

The results of the reaction of carbon dioxide with hydrogen in the presence of the catalysts 11-67 are listed in the following Tables 3 to 7. The conversions (X) and yields (Y) were educt-based and the selectivity (S)

calculated product-based.

Table 3: Results of the catalytic tests. Reaction conditions: p = 10 bar, T = 300 ° C., H ₂ : C0 ₂ : N ₂ = 71: 24: 5, GHSV = 1320 ml g of ^{"1 h-1}

Table 4: Results of the catalytic tests. Reaction conditions: p = 10 bar, T = 300 ° C, H ₂ : CO ₂ : N ₂ = 71: 24: 5, GHSV = 1320 ml g ^{"1 h-1}

Table 5: Results of the catalytic tests. Reaction conditions: p = 10 bar, T = 350 ° C, H ₂ : C0 ₂ = 3, GHSV = 660 ml gRat ^{-1 h-1}

Table 6: Results of the catalytic tests. Reaction conditions: p = 15 bar, T = 350 ° C, H ₂ : C0 ₂ = 6, GHSV = 1320 ml g _K at ^{_1 n_1}

Table 7: Results of the catalytic tests. Reaction conditions: p = 15 bar, H ^ CC ^ e, GHSV = 1320 ml gcat ^{"1 n_1}

Claims

1. A process for the preparation of hydrocarbons from carbon dioxide and hydrogen, wherein the carbon dioxide with

Hydrogen is reacted in the presence of a catalyst, wherein the catalyst contains iron and at least one alkali metal and further satisfies at least one of the following features (i) to (iii):

(i) the catalyst contains, based on the

(ii) the catalyst comprises TiC> 2 and / or a

Aluminum magnesium hydroxycarbonate as catalyst support;

(iii) the catalyst further contains ruthenium and / or cobalt.

2. The method according to claim 1, wherein the reaction of the carbon dioxide with hydrogen in the presence of the catalyst at a temperature of 150 to 400 ° C, preferably 320 to 370 ° C, and a pressure of 10 to 50 bar, preferably 15 to 30 bar , he follows.

3. The method according to claim 1 or 2, wherein the molar ratio of the hydrogen used to carbon dioxide is 4 to 8.

4. The method according to any one of claims 1 to 3, wherein a product mixture is obtained, the

Hydrocarbons, carbon monoxide, unreacted

Containing carbon dioxide and unreacted hydrogen, and after separation of the hydrocarbons unreacted carbon dioxide, unreacted hydrogen and carbon monoxide are fed back to the reactant mixture.

5. The method according to any one of claims 1 to 4, wherein the hydrocarbons C2-C4 comprise hydrocarbons.

6. The method according to claim 5, wherein the C2-C4

Hydrocarbons C2-C4 alkanes and C2-C4 contain alkenes and the C2-C alkanes are subsequently dehydrogenated after their separation to C2-C4 alkenes, in particular to ethylene, propylene and butenes.

A process according to any one of claims 1 to 4, wherein the hydrocarbons C5-C15 comprise hydrocarbons.

A process according to any one of claims 1 to 7, wherein the at least one alkali metal in the catalyst is potassium.

9. A method according to any one of claims 1 to 8, wherein the catalyst comprises:

• magnesium;

• zinc;

• zirconium, manganese and zinc;

• copper;

Copper and another representative selected from the group consisting of aluminum, lanthanum, zirconium, zinc and magnesium;

• copper, magnesium and manganese; or

• Copper, zirconium and manganese.

A process according to any one of claims 1 to 9, wherein the catalyst satisfies feature (i) or (iii) and comprises a catalyst support.

11. The method according to claim 10, wherein the

Catalyst support is selected from the group consisting from A1 ₂ 0 _3, Al ₂ 0 ₃ -MgO, Ti0 _2, La 0 _3, Zr0 _2, Zr0 ₂ -La ₂ 0 _3, Zr0 ₂ - Si0 _2, zeolites and aluminum Magnesiumhydroxycarbonaten.

12. The method according to claim 10, wherein the

Catalyst support is selected from the group consisting of Ti0 ₂ , A1 ₂ 0 ₃ and aluminum magnesium hydroxycarbonate.

13. Catalyst of the catalyst components, based on the total weight of the catalyst, at least 10 wt .-%, preferably 15-35 wt .-% iron, and potassium, copper and at least one further component selected from magnesium, zinc, lanthanum and zirconium includes.

14. A catalyst according to claim 13, which is a

Catalyst carrier comprises, on which the catalyst components are applied.

15. Catalyst according to claim 14, wherein the

Catalyst support is selected from the group consisting of Ti0 ₂ , Al ₂ 0 ₃ and / or aluminum magnesium hydroxycarbonate.