METHOD AND FACILITY FOR PRODUCING A TARGET COMPOUND

Abstract

The invention relates to a method (100) for producing a target compound, wherein a paraffin is subjected to an oxidative dehydrogenation (1) with oxygen to obtain an olefin, and wherein the olefin is subjected to a hydroformylation (2) with carbon monoxide to obtain an aldehyde, wherein the paraffin and the olefin have a carbon chain having a first carbon number and the aldehyde has a carbon chain having a second carbon number which is one greater than the first carbon number. It is provided that carbon dioxide is formed as a by-product in the oxidative dehydrogenation (1), that the carbon dioxide is subjected to dry reforming (3) at least in part with methane to obtain carbon monoxide and hydrogen, and that the carbon monoxide obtained in the dry reforming (3) and/or the hydrogen obtained in the dry reforming (3) is supplied to the hydroformylation (2). A corresponding installation is also the subject matter of the invention.

Claims

1. A method for producing a target compound, the method comprising: subjecting a paraffin to an oxidative dehydrogenation process with oxygen to obtain an olefin, subjecting the olefin to a hydroformylation process with carbon monoxide and hydrogen to obtain an aldehyde, wherein the paraffin and the olefin comprise a first carbon chain having a first carbon number and wherein the aldehyde comprises a second carbon chain having a second carbon number, wherein the second carbon number is one greater than the first carbon number, forming in the oxidative dehydrogenation process carbon dioxide as a by-product, subjecting the carbon dioxide at least in part to a dry reforming process with methane to obtain carbon monoxide and hydrogen, and supplying at least in part to the hydroformylation process, at least one selected from the group of the carbon monoxide or hydrogen obtained in the dry reforming process or mixtures thereof.

2. The method of claim 1, wherein the aldehyde is the target compound, or further comprising reacting the aldehyde to produce the target compound.

3. The method of claim 2 further comprising, reacting the aldehyde in a hydrogenation process to produce an alcohol having a third carbon chain having the second carbon number.

4. The method of claim 3 further comprising: reacting the alcohol in a dehydration process to produce a second olefin having a fourth carbon chain having the second carbon number.

5. The method according to claim 1, wherein the first carbon number is two and the second carbon number is three.

6. The method of claim 1 further comprising: separating the methane and the paraffin from natural gas.

7. The method of claim 1 wherein the carbon monoxide obtained in the dry reforming process is obtained in a first product mixture comprising hydrogen.

8. The method of claim 7 further comprising: subjecting the first product mixture from the dry reforming process to a water gas shift to obtain a second product mixture.

9. The method of claim 8 further comprising: supplying a third product mixture comprising at least one selected from the group of the first product mixture from the dry reforming process and the second product mixture from the water gas shift to the hydroformylation process, wherein the first product mixture and the second product mixture are at least partially unseparated.

10. The method of claim 1 further comprising: obtaining the olefin obtained in the oxidative dehydrogenation process in a product mixture, wherein the product mixture comprises the olefin, carbon dioxide, and carbon monoxide, separating off at least partially the carbon dioxide at a location chosen from upstream, or downstream, or combinations thereof relative to the hydroformylation process, subjecting the carbon dioxide to the dry reforming process, and subjecting at least partially the carbon monoxide and the olefin to the hydroformylation process without prior separation from each other.

11. The method according to claim 1 further comprising: passing at least part of the paraffin through the oxidative dehydrogenation process and the hydroformylation process unreacted, separating the paraffin off downstream of the hydroformylation process, and recycling the paraffin into the oxidative dehydrogenation process.

12. The method of claim 1 further comprising: compressing the product mixture from the oxidative dehydrogenation to a pressure level at which the carbon dioxide is separated off and the hydroformylation process is carried out, and wherein the dry reforming process is carried out at a lower pressure level.

13. The method of claim 1, wherein the method is carried out completely non-cryogenically downstream of the oxidative dehydrogenation process and the dry reforming process.

14. A system for producing a target compound comprising: the system configured to subject a paraffin to an oxidative dehydrogenation process with oxygen to obtain an olefin, and to subject the olefin to a hydroformylation process with carbon monoxide and hydrogen to obtain an aldehyde, wherein the paraffin and the olefin have a carbon chain having a first carbon number and the aldehyde has a second carbon chain having a second carbon number, wherein the second carbon number is one greater than the first carbon number, the system further configured to form carbon dioxide as a by-product in the oxidative dehydrogenation process, and further configured to subject the carbon dioxide to a dry reforming process at least in part with methane to obtain carbon monoxide and hydrogen, and to supply at least one of the carbon monoxide or hydrogen obtained in the dry reforming process, or mixtures thereof at least in part to the hydroformylation process.

15. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0062] FIG. 1 illustrates a method according to one embodiment of the invention in the form of a schematic flowchart.

[0063] If reference is made below to process steps, such as oxidative dehydrogenation, dry reforming or hydroformylation, these are also to be understood to cover the apparatus used in each case for these process steps (in particular, for example, reactors, columns, scrubbing devices, etc.), even if this is not expressly referred to. In general, the explanations relating to the method apply to a corresponding installation in the same way in each case.

DETAILED DESCRIPTION OF THE DRAWINGS

[0064] FIG. 1 illustrates a method according to a particularly preferred embodiment of the present invention in the form of a schematic flowchart and is designated overall by 100.

[0065] Central process steps or components of the method 100 are an oxidative dehydrogenation, which is designated here overall by 1, and a hydroformylation, which is designated here overall by 2. The method 100 further comprises a dry reforming, designated here overall by 3.

[0066] In the example shown, a natural gas stream A is supplied to the method 100. Instead of or in addition to natural gas stream A, however, a separate methane stream B and an ethane stream C can also be provided. The invention is described again here with reference to ethane as paraffin feed, but can, as mentioned, also be used in the case of higher paraffins. Further, in the example illustrated here, a vapor stream B1 and a carbon dioxide stream B2 are provided from an external source.

[0067] The natural gas stream is first subjected to fractionation 101, in particular in a corresponding column, a methane stream being obtained as overhead product and a material stream containing the heavier hydrocarbons of the natural gas stream, in particular ethane, being obtained as bottom product. The overhead stream is denoted by D here and the bottom stream by E. The material stream E, which may also predominantly or exclusively contain ethane, is fed together with a recycle stream F to the oxidative dehydrogenation 1. In this case, mixing with oxygen, which is provided in the form of a material stream G, and with vapor, which is provided in the form of a material stream H, is carried out. The vapor of the material stream H, like nitrogen of an optionally provided nitrogen stream I, serves as a diluent or moderator and in this way prevents in particular a thermal runaway in the oxidative dehydrogenation 1. Particularly in the case of the aforementioned MoVTeNb mixed metal oxide catalysts, steam furthermore has the function of ensuring catalyst stability (long-term performance), and a moderation of the catalytic selectivity is possible by means of steam.

[0068] Downstream of the oxidative dehydrogenation, an aftercooler 102 is provided downstream of which there is, in turn, a condensate separation 103. A condensate stream K formed in the condensate separation 103, which predominantly or exclusively contains water and acetic acid, can be fed to an acetic acid recovery 104 in which, in particular, a water stream M and an acetic acid stream N are formed.

[0069] The product mixture of the oxidative dehydrogenation 1 freed of condensate is compressed in the form of a material stream L in a compressor 105 and subsequently supplied to a carbon dioxide removal, designated overall by 106, which can be carried out, for example, using corresponding scrubbing. In the embodiment shown here, a scrubbing column 106a for an amine scrubbing and the regeneration column 106b for the amine-containing scrubbing liquid loaded with carbon dioxide in the scrubbing column 106a are shown. An optional scrubbing column 106c for fine purification, for example for a caustic scrubbing, is also shown. As mentioned, carbon dioxide removal and recovery by appropriate scrubbing is generally known. It is therefore not explained separately.

[0070] A carbon dioxide stream O formed in the carbon dioxide removal 106 can, as explained further below, be fed into the dry reforming 3.

[0071] A mixture of components remaining in the form of a material stream P, after the removal of carbon dioxide in the carbon dioxide removal 106, contains predominantly ethylene, ethane and carbon monoxide. It is optionally dried in a dryer 107 and subsequently supplied together with a further material stream V (see below) to the hydroformylation 2.

[0072] In the hydroformylation 2, propanal is formed from the olefins and carbon monoxide and hydrogen, which together with the further components explained is carried out in the form of a material stream Q from the hydroformylation 2. Unreacted ethane, in particular ethane unreacted in the oxidative dehydrogenation 1, can optionally be separated from the material stream Q in a separation 108 and this ethane can be transferred into the recycle stream F. This recycle stream F also contains any further substances present and which boil more easily than propanal. Alternatives to the separation 108 are discussed further below, however, the separation 108 is a preferred embodiment.

[0073] In a hydrogenation 109, the propanal can be converted to propanol. The alcohol stream is fed to a further separation 110, optionally provided as an alternative to the separation 108, where ethane, in particular ethane unreacted in the oxidative dehydrogenation 1, and any further substances present, can be separated more easily than propanol and transferred into the recycle stream F.

[0074] The hydrogenation 109 can be operated with hydrogen which is contained in a product stream of the dry reforming 3 and is carried along in the hydroformylation. Alternatively, the separate feeding of required hydrogen in the form of a material stream R is also possible, in particular from a separation of hydrogen in a pressure swing adsorption 111.

[0075] A product stream from the hydrogenation 109 or from the optionally provided separation 110 is fed to a dehydration 112. In said dehydration, propylene is formed from the propanol. A product stream S from the dehydration 112 is fed to a condensate separation 113 where it is freed of condensible compounds, in particular water. The water can be carried out of the process in the form of a water stream T. The water streams N and T can, optionally after a suitable work-up, also be fed again to the process for steam generation. In this way, for example, at least a part of the steam flow B1 can be provided.

[0076] The gaseous residue remaining after the condensate separation 113 is fed to a further separation 114 optionally provided as an alternative to the separations 108 and 110 where, in turn, ethane unreacted particularly in the oxidative dehydrogenation 1 can be separated off and transferred into the recycle stream F. A product stream U formed in the separation 114 can be carried out of the process and used in further process steps, for example for the production of plastics or other further compounds, as indicated here overall by 115. Corresponding methods are known per se in a variety of forms and comprise the use of the propylene from the method 100 as intermediate product or starting product in the petrochemical value chain.

[0077] Ethane unreacted in the oxidative dyhdrogenation 1 is, as mentioned several times, recycled with the material stream F into the oxidative dehydrogenation 1.

[0078] A water gas shift 116 is optionally connected downstream of the dry reforming 3. A product mixture V formed in each case in the dry reforming 3 or the (optional) water gas shift 116, which predominantly or exclusively contains hydrogen and carbon monoxide, is fed (after an optional hydrogen separation in the pressure swing adsorption 111), together with the material stream P freed of carbon dioxide, from the oxidative dehydrogenation 1 to the hydroformylation 3.