EP2173690A1

EP2173690A1 - Regeneration of catalysts for dehydrating alkanes

Info

Publication number: EP2173690A1
Application number: EP08785012A
Authority: EP
Inventors: Helmut Gehrke; Max Heinritz-Adrian; Muhammad Iqbal Mian; Oliver Noll; Rolf Schwass; Sascha Wenzel
Original assignee: Uhde GmbH
Current assignee: ThyssenKrupp Industrial Solutions AG
Priority date: 2007-08-03
Filing date: 2008-07-24
Publication date: 2010-04-14
Also published as: WO2009018924A1; DE102007036750A1; CN101765576A; US9181149B2; RU2477265C2; KR101581054B1; US20100234660A1; HK1140752A1; WO2009018924A4; AR067723A1; MY156347A; JP2010535208A; BRPI0814765A2; KR20100038397A; RU2010107622A; JP5493099B2; CN101765576B; EG26205A

Abstract

The invention relates to a method for dehydrating alkanes, wherein the alkane is guided in a reactor for the dehydration of alkanes via a catalyst, and the process may be carried out adiabatically or non-adiabatically, and the catalyst for dehydration can be regenerated after the reaction phase by means of transferring a gas, wherein said gas is guided via the catalyst after a short rinsing phase using water vapor, and said regeneration gas consists of a gas containing oxygen and of steam, and after regeneration the catalyst is freed of the gas containing oxygen by transferring steam, wherein the duration of the transfer of a gas containing oxygen is significantly reduced as compared to common methods and represents 70% or less of the total regeneration time, and the catalyst has an increased selectivity for forming alkene by means of carrying out the regeneration at a constant activity, and the catalyst is comprised of a metal of the group of platinum metals or of the group VIB of the periodic table of the elements, which is applied to a carrier in the form of a compound or in elementary form, which substantially consists of oxides of the elements of tin, zinc, or aluminum.

Description

Regeneration of catalysts for the dehydrogenation of alkanes

In the catalytic dehydrogenation of hydrocarbons according to the formula

C _n H _{2n + 2} <r> C _n H _2n + H ₂ , (1) which is usually carried out in the gas phase at a temperature of 450 ° C to 820 ⁰ C, it is a strongly endothermic equilibrium reaction whose conversion is thermodynamically limited and depends on the respective partial pressures and the temperature. The dehydrogenation reaction is favored by low partial pressures of the hydrocarbons and by high temperatures.

[0002] The dehydrogenation reaction can be carried out both adiabatically and nonadiabatically or approximately isothermally. If the dehydrogenation is carried out in an adiabatically operated catalyst bed, the temperature decreases over the length of the catalyst bed by the endothermic reaction. The conversion in the catalyst bed is thus limited, so that several catalyst beds are necessary for the desired high conversions and a renewed heating must take place behind each catalyst bed. In order to achieve reasonable reaction conversions, one usually switches several catalyst beds one behind the other and heats up the reaction system behind each catalyst bed.

If the dehydrogenation is carried out in a nonadiadiabatically operated catalyst bed, the catalyst bed can be heated to maintain a high temperature. The reaction then proceeds with high conversions due to the temperature kept constant over the reaction system. The disadvantage, however, is that these high conversions can only be achieved at high temperatures due to the position of the thermodynamic equilibrium, which reduces the selectivity of olefin formation. Subsequent reactions then occur increasingly, leading to the formation of undesirable products such as CH ₄ , CO, CO ₂ , C ₂ H ₄ , C ₂ H ₆ and coke.

The by-products formed in this way, in particular finely divided coke, deposit on the catalyst in the course of the reaction, so that its state changes continuously. The catalyst is overcoated with an undesirable coating. which makes it less accessible to the reactants. The catalyst thus suffers a deactivation. The activity of the catalyst for the alkane dehydrogenation and the selectivity for alkene formation may deteriorate. The result is a reduction in the yield of the entire process. Due to operational requirements, this deactivation can only be tolerated up to a certain limit, because thereafter an economic operation of the plant is no longer guaranteed. Therefore, to counteract adversely affecting the process, the catalyst must be regenerated to regain its activity after a certain reaction time.

Depending on its nature, the regeneration of the catalyst is carried out in such a way that an oxygen-containing gas is brought into contact with the catalyst in conditions defined for the regeneration process. The conditions for this regeneration may differ from those of dehydration. Frequently, a vapor-diluted oxygen-containing gas is also passed over the catalyst. This procedure degrades the byproducts on the catalyst so that it can regain its activity. If an oxygen-containing gas diluted with steam is used to regenerate the catalyst, the carbonaceous coating reacts to form carbon dioxide as the main product. The carbonaceous material is transformed into gaseous products by this reaction and discharged from the system.

Since the conditions for carrying out the reaction of the alkane dehydrogenation differ from those for the regeneration of the catalyst, the process of alkane dehydrogenation is interrupted after a certain period and replaced by the process of catalyst regeneration. Thereafter, the reactor bed is again available for dehydration. Both processes, both the alkane dehydrogenation and the catalyst regeneration are thus carried out periodically. In order to make the entire process economically efficient, it can be operated with two or more catalyst beds, in which the processes of reaction and regeneration are carried out in cyclic alternation. To ensure optimum catalyst regeneration, an optimum production and regeneration sequence must be defined.

To optimize the system several catalyst sections are used, the processes of dehydrogenation and regeneration in the cyclic Change be operated. Some of the catalyst runs can be used to perform the alkane dehydrogenation, while at the same time other catalyst runs can be regenerated by passing an oxygen-containing gas or vapor-diluted oxygen-containing gas. It is also possible to remove the catalyst coating by a reductive process, although an oxidative process is usually faster and more effective. If a catalyst section has already undergone the regeneration process before a further catalyst section is to be regenerated, this can be kept available by further passing an oxygen-free gas through the catalyst bed, so that a reaction path is always available.

Examples of such processes can be found in the patent literature. DE 19858747 A1 describes a process for the catalytic dehydrogenation of alkanes by a nonadiabatically guided process. To extend the duration of the dehydrogenation period, steam and hydrogen are added to the process gas. The dilution of the reaction mixture with these associated gases leads to prolonged service life of the catalyst, since the deposited carbonaceous deposits partially react with the associated gases to carbon monoxide and water and discharged. After a certain reaction time, the catalyst is completely regenerated by stopping the dehydration and passing an oxygen-containing gas. In a subsequent rinsing step, after regeneration, hydrogen or a mixture of hydrogen and alkanes are passed through the catalyst bed for reductive purification of the catalyst surface. These processes can be performed cyclically over several reactor sections.

US 5235121 A describes a process for the catalytic dehydrogenation of alkanes by a nonadiabatically guided process. For regeneration of the catalyst is used diluted with steam oxygen-containing gas. In order to reduce the heat loss during dehydration, part of the regeneration gas that heats up is returned to the dehydrogenation process. In a subsequent rinsing step, a hydrogen-rich reforming product is passed through the catalyst bed after regeneration. These processes can be carried out cyclically over several reactor sections. Alkanes as starting materials are preferably used with a C-number to Ci. ₂ US 4229609 A describes a process for the catalytic dehydrogenation of alkanes by a nonadiabatically guided process. To regenerate the catalyst, a sequential sequence of gas purges is passed through the catalyst bed. First, the catalyst is freed from the alkane by passing water vapor-containing gas, then regenerated by passing oxygen-containing gas and then freed by passing water vapor from the oxygen-containing regeneration gas. A specification for the duration of the individual regeneration phases is not suggested. An experimental example (column 3), however, shows an embodiment with a 30 minute dehydration reaction, followed by a regeneration phase by a 1 minute steam purge, a 28 minute oxygen pass gas, and a 1 minute steam purge , The processes dehydrogenation and catalyst regeneration can be performed in cyclic change over several reactor sections. The starting materials used are preferably alkanes having a C number of C ₆ to C ₉ .

Regardless of the chosen mode of operation of the process, it is found that, despite regeneration, after some time the catalyst suffers a loss with respect to the dehydrogenation reaction to be catalysed. The regeneration often takes place under conditions that adversely affect the nature of the catalyst. Thus, for example, an oxygen-containing gas is passed over the catalyst under greatly increased temperature, whereby the catalyst can change chemically. In addition, temperature control of the catalyst bed is not always easy due to the exothermic process of the burnup. The catalyst can therefore be baked and, despite regeneration, lose its desired activity after a few cycles. The selectivity to the desired process of olefin formation may then decrease.

Object of the present invention is therefore to find regeneration conditions in which the activity of the catalyst and the selectivity for the desired process of dehydrogenation is maintained even after many regeneration cycles. The procedure to be found should influence the catalyst activity and selectivity as much as possible so that these parameters can be optimally adapted to the process. The regeneration process should keep the catalyst activity constant for as many cycles as possible and reduce the formation of carbonaceous deposits. It has now been found that the object of the invention can be achieved if it leads to the regeneration of oxygen-free and oxygen-containing gases in a certain time ratio over the catalyst. As a result of the procedure according to the invention, the activity of the catalyst for converting alkanes for the process is set appropriately. The selectivity for the desired dehydrogenation process is not only obtained by the procedure according to the invention, but also optimized so that overall a high yield of desired alkene is always obtained and the formation of by-products is suppressed. In regeneration of the catalyst system according to the invention, the adjustment of the equilibrium of the dehydrogenation after transfer through the reactor bed is made possible as far as possible even over many regeneration cycles. Thus, a total improved under economic aspects driving the system can be achieved.

The invention achieves the object with a method in which • a hydrocarbon, in particular alkanes, containing mixture, which

May contain water vapor and has substantially no oxygen, is passed in a continuous mode through a catalyst bed, which has conventional dehydrogenation conditions, and

which is characterized in that

• immediately after the dehydration reaction after several hours

Production phase of the dehydrogenation followed by a short phase with passing an oxygen-free gas stream through the reactor bed for rinsing and removal of the reaction gas from the reactor bed, and

• followed by a phase with passing over an oxygen-containing reaction gas to remove the catalyst coatings, and

Followed by a subsequent phase of passing an oxygen-free gas stream for purging and removing the regeneration gas from the reactor, wherein

• the time duration of the transfer of an oxygen-containing gas in the regeneration of the catalyst is 70% of the total duration of the regeneration or less. In one embodiment of the invention, the time duration of the regeneration of the catalyst by transferring an oxygen-containing gas in relation to the total duration of the regeneration is preferably 20 to 70%. The prerequisite for obtaining the effect according to the invention is that the removal of the carbonaceous deposits on the catalyst by the regeneration is as complete as possible.

The inventive method is well suited for the regeneration of various dehydrogenation catalysts. The catalysts should provide sufficient activity and selectivity for the desired process of alkane dehydrogenation. In addition, they should survive the process of oxidative combustion of coke unscathed and can be easily regenerated to achieve long service life. Depending on the dehydration process used, it is expedient to choose the catalyst so that it is optimally suitable for the process used. A selection of various dehydrogenation processes and the catalysts used therein can be found in the publications F. Buonomo, D. Sonfillipo, F. Trifirό, Handbook of Heterogeneous Catalysis, 1 ^st Edition, VCH, Weinheim, 1997 p. 2140 ff. And the references cited therein.

US 5151401 A describes a catalytic system with high catalytic activity and good selectivity for dehydrogenation reactions. The catalyst is applied to a support to ensure good handling of the system. The support material is prepared by calcination of a mixture of tin oxide, zinc oxide and aluminum oxide. In a subsequent step, a chlorinated platinum compound is applied as a catalytically active material. The catalyst is then removed by a washing and drying process of chlorine, which can be corrosive in the application process. For optimal handling, the carrier material can be used in the form of pellets, tablets or extrudates. The supported catalyst may also contain additives to improve stability. Such substances may be long chain carboxylic acid salts or calcium aluminates.

US 4973779 A describes another catalytic system with high catalytic activity and good selectivity for dehydrogenation reactions. The support material consists of calcined γ-alumina, in which a tin compound in the form of an oxide, halide, sulfide or a similar composition is distributed. In a subsequent step, a chlorinated platinum compound and a ne chlorinated iridium compound applied as a catalytically active material. To improve the catalytic activity, the support material is still provided with an alkali metal salt or preferably with a lithium salt before the calcination.

DE 3526533 A1 describes another catalytic system with high catalytic activity and good selectivity for dehydrogenation reactions of C ₃ -C ₅ alkanes. The support material consists of η-alumina, which is sprayed with an aqueous solution of chromium (VI) oxide and dried. During drying, chromium oxides are formed from the chromium salt solution, which are finely distributed in the carrier material and produce the actual catalytic activity.

All of the catalysts mentioned or the catalysts cited in the cited patents can be easily regenerated by the process according to the invention and lead to the results according to the invention.

For practical implementation of the process according to the invention, several embodiments can be selected depending on the catalyst. In one embodiment of the invention, the process gas is passed adiabatically through the catalyst bed, wherein the process gas is subjected to a heating process before passing through the catalyst bed.

In a further embodiment of the invention, the process is performed non-diabatically. Since the dehydrogenation reaction is endothermic, heat must be added and the catalyst bed heated.

It is also possible to overcome the thermodynamic limitation of the dehydrogenation step in that a part of the hydrogen formed in the dehydrogenation according to

2 H ₂ + O ₂ → 2 H ₂ O (2) is selectively burned. The abbreviation SHC for "Selective Hydrogen Combustion" is also used to denote this, since the reaction consumes hydrogen, the equilibrium of the dehydrogenation shifts toward higher conversions, that is towards the formation of olefins also releases heat, which heats up the reaction mixture, which still contains unreacted alkane, and the processes of endothermic dehydrogenation of Alkanes and the exothermic selective hydrogen combustion can be combined in this way, so that the process proceeds almost autothermally

To facilitate the process, the process steps of the dehydrogenation and the oxidative combustion of the resulting hydrogen are frequently carried out successively successively. The reaction gas is first passed through a catalyst bed for dehydrogenation. After the dehydrogenation, the product gas is provided with an oxygen-containing gas The reaction gas heats up the reaction gas (SHC) (2). As a result, the product gas can be fed to the dehydrogenation after the process of the SHC for a repeated process step, whereby correspondingly less heat input is required for this process step

WO 2004/039920 A2 describes, by way of example, a process for the catalytic dehydrogenation of hydrocarbons with subsequent oxidation of the hydrogen formed in the dehydrogenation step. In a first process step, an alkane-containing gas mixture is passed over a catalyst bed which is suitable for alkane dehydrogenation (1). After the process step of the dehydrogenation, the hydrogen- and alkane-containing product gas is mixed with an oxygen- and water vapor-containing gas and passed through a second catalyst bed which is suitable for It is characteristic of the process that the same catalyst is used for the dehydrogenation (1) and the oxidative hydrogen combustion (2) process steps. The combustion of hydrogen heats the Re The product mixture is subjected after hydrogen oxidation to a new process step of the dehydrogenation, where it can either be recycled back to the reactor of the first process stage, or into a separate separate reactor for dehydrogenation

The combination of the alkane dehydrogenation with a process stage of selective hydrogen combustion (SHC) (2) is well suited for carrying out the process according to the invention, in order to drive the process in an energy-efficient manner and with high conversions For carrying out the oxidative hydrogen combustion (2), a catalyst can be used which is suitable both for carrying out a dehydrogenation of alkanes and for the oxidative hydrogen combustion. Also suitable for oxidative hydrogen combustion is a catalyst which selectively oxidizes hydrogen, as used, for example, in WO 96/33150 A1.

Important for the inventive method is that the duration of the regeneration phase and the subsequent rinsing phase is adjusted so that the activity of the catalyst for dehydrogenation is maintained even after many regeneration cycles and the selectivity for the process of dehydrogenation are optimally adjusted can. The procedure according to the invention of the process makes it possible to achieve an almost complete adjustment of the equilibrium for alkane dehydrogenation after each regeneration phase and to minimize the formation of by-products.

In one embodiment of the invention, the alkane to be dehydrogenated is mixed with steam prior to dehydrogenation and thereby diluted. The percentage molar ratio of steam to alkane can be 1 to 99 in one embodiment of the process according to the invention. For a further optimization of the reaction, the molar ratio of steam to alkane may be 1 to 10 and ideally 2 to 6.

In a further embodiment of the invention, the oxygen-containing gas of the regeneration phase is diluted with steam. If steam is selected as the accompanying gas for the oxygen-containing gas, the percentage molar ratio between gas and steam is preferably 0.01 to 50 mole percent oxygen to 99.99 to 50 mole percent steam. To further optimize the reaction, the mole ratio of oxygen to steam may be 0.05 to 35 mole percent oxygen to 99.95 to 65 mole percent steam, and ideally 0.5 to 25 mole percent oxygen to 99.5 to 75 mole percent steam.

In a further embodiment of the invention, the oxygen-containing gas of the regeneration phase is diluted with nitrogen or a noble gas or another inert gas. If nitrogen or an inert gas is chosen as the accompanying gas for the oxygen-containing gas, the percentage molar ratio between oxygen and nitrogen or the inert gas is preferably from 0.01 to 50 mol% of oxygen 99.99 to 50 mole percent nitrogen or the inert gas. To further optimize the reaction, the molar ratio between oxygen and nitrogen or the inert gas may be 0.05 to 35 mole percent oxygen to 99.95 to 65 mole percent nitrogen or the inert gas, and ideally 0.5 to 25 mole percent oxygen to 99.5 75 mole percent nitrogen or the inert gas.

As starting material for the alkane dehydrogenation according to the invention alkanes can be used with a C number range of C ₂ to C ₂ o. In one embodiment of the invention are used as starting material ethane or propane or butane or a mixture of these gases. The inventive method is particularly suitable for the production of ethene or propene or butenes or a mixture of these gases.

A catalyst is used for the process, which is characterized in that it is suitable in the process according to the invention for the dehydrogenation of alkanes. In general, these contain a metal from group VIIIB of the Periodic Table of the Elements. For better handling, the catalytically active material can be applied to a support of oxides of the elements aluminum, silicon, magnesium, zirconium, zinc or tin. As a catalyst for the process according to the invention, a catalyst can be used with particular advantage, as described by way of example in the above-mentioned US Pat. No. 5,151,001 A. However, any other catalyst suitable for alkane dehydrogenation may be used. Catalysts which contain metals from group VIB of the periodic table may be mentioned as examples here. The catalytically active material may be applied for better handling on a support of oxides of the elements aluminum, silicon or magnesium.

To carry out the process according to the invention, a pressure is used which corresponds to the usual conditions for the dehydrogenation of alkanes. Typically, pressures of 0.1 to 15 bar are used. This pressure can be maintained to carry out the catalyst regeneration.

To carry out the dehydrogenation reaction for the inventive

Method is selected a temperature range, as it corresponds to ordinary conditions for the dehydrogenation of alkanes. Typically, temperatures of 450 to 820 ⁰ C are selected here. To carry out the regeneration are usually Temperatures selected from 450 to 750 ⁰ C. In a non-adiabatic mode of operation, an increase in the temperature of the regeneration gas may occur during regeneration by heating the catalyst bed.

In one embodiment of the invention, the dehydrogenation (1) is carried out nonadiabatically in a first reaction stage and subsequently a gas for cooling is added to this product mixture obtained from the first reaction stage. This gas is preferably oxygen and water vapor. If a further cooling of the reaction gas is required, liquid water can also be added to the reaction gas. The cooled reaction gas may then be passed to a second process stage for carrying out an oxidative hydrogen combustion (2).

In a further embodiment of the invention, the process step of oxidative hydrogen combustion is followed by a third process step of renewed alkane dehydrogenation. For this purpose, the process gas is heated either directly or indirectly by an oven.

The inventive method is characterized by a simple feasibility and high efficiency. The type of catalyst regeneration described makes it possible, while maintaining the activity, not only to maintain the selectivity of a conversion of alkane to alkene over many regeneration cycles, but even to improve it. Overall, a higher yield of desired alkene is thus obtained. Thus, a total of a significantly improved driving style of the system is achieved under economic aspects.

The method according to the invention is described below by some executing examples, but the invention is not limited to these. These are only typical embodiments.

For the experimental examples, a model reactor was used, as it is typically used for the testing of dehydrogenation reactions. This consists of a heatable metal tube, which is acted upon in the interior with the catalyst. The metal tube is placed vertically and is provided on the upper side with a feed device to direct the mixture to be dehydrogenated through the catalyst bed. The supply device is provided with a device for heating, even at room temperature solid hydrocarbons through the To be able to conduct the reactor. On the inlet and outlet side are devices that allow to measure and adjust the pressure and temperature of the gas passed through. Via a four-way valve, the feed of the hydrocarbon can be stopped and replaced by passing an oxygen-containing regeneration gas or a purge gas. Via a further independent feed device, a diluent gas can be introduced into the gas stream. The reaction products are collected at the exit end of the reactor. There is a device for performing a gas chromatographic measurement, which analyzes the reaction product. As a result, molar concentrations are displayed, which can be converted into percent reaction conversions and selectivities.

The invention is demonstrated by means of several experiments. Propane is mixed with steam and passed through the reactor via the feed device. The exact reaction conditions can be found in Table 1.

Table 1

In a first experiment with three examples, propane was dehydrated for 7 hours. This was followed by a 5-minute rinsing phase with steam, a regeneration phase with an oxygen-containing and water vapor-containing gas, and a further rinsing phase with steam, each with a different duration. In a renewed dehydrogenation period, the conversion of propane and selectivity to propene were then measured (Table 2).

Example 1: Comparative Example Example 2 Inventive Example Example 3 Counter Example

Table 2

¹⁾ Previously a 5-mιnutιge winding phase with water vapor, regeneration gas consists of air / water vapor with a total of 2 VoI -% oxygen

²⁾ Spulgas consists of water vapor

The selectivity for olefin formation is highest at almost the same conversion in the inventive example and the counter-example according to the invention. The counter-example with extended winding phase demonstrates sinking catalyst activity

In a further experiment (Table 3), an alkane dehydrogenation without catalyst regeneration was performed near the thermodynamic equilibrium. After 280 min, 510 min and 740 min, the product gas was sampled. The conversion remains approximately the same, while the selectivity increases significantly

Table 3

In another experiment (Table 4), propane was dehydrogenated, the catalyst regenerated without oxygen supply and in a renewed cycle, the propane is de-hydrazated. The activity of the catalyst decreases markedly as a result of the weaker coke removal

Table 4

¹⁾ measurement after 280 min, ²⁾ regeneration with oxygen-free gas

Claims

claims

1. A process for the dehydrogenation of alkanes, wherein

• a hydrocarbon, in particular alkanes, containing mixture which

Contains water vapor and has substantially no oxygen, is passed in a continuous mode through a catalyst bed, which has conventional dehydrogenation conditions,

characterized in that

• following a dehydrogenation production phase lasting several hours, a phase of passing an oxygen-free gas through the reactor bed to purge and remove the reaction gas from the reactor bed, and

Followed by a phase of passing an oxygen-containing regeneration gas to remove the catalyst deposits formed by the dehydrogenation reaction, and

Followed by a phase of passing an oxygen-free gas to purge and to remove the regeneration gas from the reactor, wherein

• the time duration of the transfer of an oxygen-containing gas in the regeneration of the catalyst is 70% of the total duration of the regeneration or less.

2. The method according to claim 1, characterized in that the time duration of the regeneration of the catalyst by transferring an oxygen-containing gas in relation to the total duration of the regeneration is 20 to 70%.

3. The method according to claim 1, characterized in that the oxygen-containing regeneration gas is diluted with steam.

4. The method according to claim 1, characterized in that the oxygen-containing regeneration gas is diluted with nitrogen or an inert gas.

5. The method according to claim 3, characterized in that for regeneration with an oxygen-containing gas and steam, a percentage molar ratio of 0.05 to 50 moles of oxygen to 99.95 to 50 moles of steam is selected.

6. The method according to claim 3, characterized in that for regeneration with an oxygen-containing gas and nitrogen or an inert gas, a percentage molar ratio of 0.05 to 50 moles of oxygen to 99.95 to 50 moles of nitrogen or an inert gas is selected.

7. The method according to any one of claims 1 to 6, characterized in that instead of pure oxygen, the same molar fraction of oxygen is supplied by air.

8. The method according to any one of claims 1 to 7, characterized in that as starting material for the alkane dehydrogenation alkanes with the C-number

Range C ₂ to C ₂ o are used.

9. The method according to any one of claims 1 to 8, characterized in that the catalyst for carrying out the process according to the invention contains a metal from the group VIIIB of the Periodic Table of the Elements.

10. The method according to any one of claims 1 to 8, characterized in that the catalyst for carrying out the method according to the invention contains a metal from group VIB of the Periodic Table of the Elements.

11. The method according to any one of claims 9 and 10, characterized in that the catalyst is coated on a support of oxides of the elements aluminum, silicon, magnesium, zirconium, zinc or tin or mixtures of these elemental oxides.

12. The method according to any one of claims 1 to 11, characterized in that the percentage molar ratio of steam to alkane in the dehydrogenation is 1 to 99.

13. The method according to any one of claims 1 to 12, characterized in that the process step of dehydrogenation is carried out nonadiabatically.

14. The method according to any one of claims 1 to 13, characterized in that the process step of dehydrogenation is carried out in an oven, which can heat the process gas to a temperature range of 450 ⁰ C to 820 ⁰ C.

15. The method according to any one of claims 1 to 12, characterized in that the process step of the dehydrogenation is carried out adiabatically.

16. The method according to any one of claims 1 to 15, characterized in that the process step of catalyst regeneration is carried out at a temperature of 450 to 750 ⁰ C.

17. The method according to any one of claims 1 to 16, characterized in that for carrying out the dehydrogenation and the regeneration, a pressure of 0.1 bar to 15 bar is selected.

18. The method according to any one of claims 1 to 17, characterized in that the dehydrogenation in a first reaction stage performed nonadiabatically and subsequently this from the first stage containing product mixture consisting of alkanes, alkenes, water vapor, hydrogen and by-products as well as water vapor and an oxygen the resulting reaction mixture is passed in a continuous procedure in a second stage through another catalyst bed for the oxidation of hydrogen and the further dehydrogenation of hydrocarbons.

19. The method according to claim 18, characterized in that subsequently to the reaction mixture obtained from the first stage, an oxygen-containing gas is mixed and the reaction mixture obtained in continuous

Driving in a second stage by another catalyst bed for the oxidation of hydrogen and subsequently passed through at least a third stage by another catalyst bed for alkane dehydrogenation.

20. The method according to any one of claims 18 and 19, characterized in that subsequent to the reaction mixture obtained from the first stage Oxygen-containing gas is mixed and the resulting reaction mixture is recycled in a continuous procedure in a second stage by another catalyst bed for the oxidation of hydrogen and subsequently in the first catalyst bed for alkane dehydrogenation.

21. The method according to any one of claims 1 to 20, characterized in that as catalysts for the catalyst bed of the first stage, any conventional dehydrogenation catalysts are used and for the second and optionally further catalyst beds such dehydrogenation catalysts are used, which not only by activity for Dehydration, but also have activity for selective hydrogen oxidation or have only for selective hydrogen oxidation.

22. Material for a process according to claim 1, characterized in that it is suitable as a catalyst for the dehydrogenation of alkanes.