Method for producing styrene using at least one heat pump

Abstract

The invention relates to a method for producing styrene starting from ethylbenzene, the method in particular having a method step of transferring heat from the obtained product gas flow to an H2O-containing flow by means of a heat pump, wherein part of the heated H2O-containing flow obtained in this manner is returned to the method. It has surprisingly been found that the amount of steam generated by the method can replace at least part of the steam required for the reaction or can even supply more than the amount used in the process. As a result, the method can have a significantly reduced or even negative CO2 footprint.

Description

Process for the production of styrene using at least one heat pump TECHNICAL AREA The present invention relates to a process for the production of styrene (according to the IUPAC nomenclature phenylethene or ethenylbenzene) using one or more heat pumps. INTRODUCTION Styrene is typically produced on an industrial scale by dehydrating ethylbenzene, which is usually diluted with steam. If the dehydration takes place under adiabatic conditions, all the heat required for the dehydration can be supplied to the one or more reactors used by adding superheated steam to the ethylbenzene. The reaction mixture exiting the reaction zone, which primarily consists of water vapor, styrene, unreacted ethylbenzene, and any byproducts formed during the reaction, is typically cooled to a temperature of approximately 100 to 120 °C by one or more heat exchangers downstream of the reactor(s). The heat transferred to the heat exchanger can be used to heat and evaporate the reactants (ethylbenzene + low-pressure steam), thus generating, for example, water vapor. The reaction mixture, cooled to approximately 100 to 120 °C, can then be condensed and cooled in a downstream condenser using cooling water or air for further processing, although the heat released in this process is lost for economic use. Alternative methods have already been described in which this heat can be used, for example, to generate the steam that is used as a diluent in the process. US 2012 / 149960 A1 and EP 2651859 B1 each relate to a process for the dehydrogenation of ethylbenzene, the process in particular comprising heat recovery. German patent DE 3147323 A1 describes a process in which a portion of the resulting reaction mixture condenses in a steam generator, while another portion containing water is evaporated to steam. In this way, a portion of the reaction mixture, which previously had a temperature of 97 °C, is cooled to 91 °C, and steam is also generated at a pressure of 0.5 bar and a temperature of 81 °C. The generated steam is then compressed to a pressure of 1.6 bar by means of a compressor. Thus, the reaction mixture starts at 97 °C. For condensation to occur, the partial pressure of water on the heat transfer fluid side must be approximately 0.92 bar. Since the molar fraction of water vapor in the mixture is approximately 80%, the total pressure at this point must be approximately 1.15 bar. However, modern dehydration processes operate at a significantly lower pressure level because this increases conversion and selectivity. Therefore, US 4,695,664 proposed evaporating an azeotropic mixture of water and ethylbenzene instead of water alone. The azeotropic mixture of water and ethylbenzene has a boiling point of only 92 °C at 1 bar. This makes it possible to utilize heat energy through condensation at lower temperatures and thus lower pressures on the reaction mixture side. According to US 4,695,664, the azeotropic mixture is heated to temperatures of 60 to 76 °C (140–170 °F), which corresponds to vapor pressures of 0.38 to 0.62 bar. For this to work, the reaction mixture on the other side of the heat transfer fluid must not be cooled below temperatures of approximately 70 to 86 °C. However, for the mixture to condense at these temperatures, the pressure on this side of the heat exchanger must be approximately 0.4 to 0.8 bar. However, at 0.4 bar on the side of the reaction mixture, the pressure on the evaporation side of the azeotropic mixture would already be at approximately...The pressure is 0.38 bar, so that a compressor that generates this negative pressure and brings the mixture to the pressure necessary for feeding into the reactor would have to be so large and complex that such a design is hardly economical. However, some modern dehydration processes operate at even lower pressure levels, making the technique described in the above documents no longer economical. A disadvantage of the industrial production of styrene is that the steam required as a diluent is typically generated in steam boilers heated with fossil fuels, consuming large amounts of primary energy. This results in the steam used having a large carbon footprint, particularly due to the fact that the mass ratio of steam to ethylbenzene can be around 1:1 or even higher. Thus, the generated steam contributes approximately 85% to the carbon footprint per kilogram of styrene produced. If the steam could be generated with significantly fewer CO2 emissions, the on-stage carbon footprint of the process would be considerably reduced. Furthermore, it is disadvantageous that the gaseous mixture obtained from the reaction, which has already been cooled to about 100 °C after the heat exchange described above, is cooled in a downstream condenser using water or air to such an extent that it condenses, whereby the heat released in the process is lost for economic use. DETAILED DESCRIPTION The present invention was therefore based on the objective of providing a process for the production of styrene that is resource-efficient, and in particular energy-efficient, and thus has a comparatively significantly reduced CO2 footprint. Furthermore, it was an objective of the present invention to enable operation at a comparatively low pressure of the reactant stream diluted with steam. The object of the present invention is achieved by integrating one or more heat pumps into a process for the production of styrene. In particular, the remaining heat of condensation can be extracted from the reaction mixture, which has already been cooled by heat exchangers, by means of one or more heat pumps, especially one or more "closed loop" heat pumps. It was surprisingly discovered that the amount of steam generated can replace some of the steam required for the reaction, supply precisely the required amount so that the process is self-sufficient, or even supply more than the amount used in the process. This can significantly reduce the CO2 footprint of the process or even make it negative. Electricity from renewable sources (e.g., green electricity, PCF-free) can be used to power the heat pump and any other components that may be required. Furthermore, it was surprisingly discovered that the process according to the invention also makes it possible to extract the remaining heat of condensation from the already cooled reaction mixture, even at low pressures, so that this energy can be used to produce steam. The present invention therefore relates to a process for the production of styrene, the process comprising (i) Providing a stream containing ethylbenzene; (ii) Provision of a water-containing stream S1 ; (iii) Introducing the streams provided in (i) and (ii) into a reactor unit comprising a catalyst, and contacting the streams with the catalyst, obtaining a product gas stream comprising styrene; (iv) optionally transferring heat from the product gas stream obtained from (iii) to the ethylbenzene-containing stream provided in (i), to the H2O-containing stream S1 provided in (ii), to an H2O-containing stream S2, to the ethylbenzene-containing stream provided in (i) and to the H2O-containing stream S1 provided in (ii), to the H2O-containing stream S1 provided in (ii) and an H2O-containing stream S2, to the ethylbenzene-containing stream provided in (i) and an H2O-containing stream S2, or to the ethylbenzene-containing stream provided in (i) and the nO-containing stream S1 provided in (ii) and an nO-containing stream S2, obtaining a cooled product gas stream; (v) Provision of an nO-containing current S3; (vi) Transferring heat from the product gas stream obtained from (iii) or from the cooled product gas stream obtained from (iv) to the FW-containing stream S3, wherein the heat transfer is carried out by means of one or more heat pumps, obtaining a heated FW-containing stream S3, wherein the heated FW-containing stream S3 obtained is preferably gaseous; (vii) optionally compressing the heated FW-containing stream S3 obtained in (vi), obtaining a compressed and heated FW-containing stream S3; (viii) Introducing at least part of the heated FW-containing stream S3 obtained in (vi) or at least part of the compressed and heated FW-containing stream S3 obtained in (vii) into the FW-containing stream S1 provided in (ii). Preferably, 90 to 100 wt%, more preferably 95 to 100 wt%, more preferably 99 to 100 wt% of the ethylbenzene-containing stream provided in (i) consists of ethylbenzene. Preferably, the ethylbenzene-containing stream FW provided in (i) comprises. If the ethylbenzene-containing stream provided in (i) comprises FW, it is preferred that 0 to 10 wt%, more preferably 0 to 5 wt%, more preferably 0 to 1 wt% of the ethylbenzene-containing stream provided in (i) consist of FW. Preferably, the ethylbenzene-containing stream provided in (i) has a mass flow rate in the range of 1 to 300 t / h, more preferably from 10 to 280 t / h, and more preferably from 20 to 240 t / h. Preferably, 90 to 100 wt%, more preferably 95 to 100 wt%, more preferably 99 to 100 wt% of the FW-containing electricity S1 provided in (i) consists of FW. Preferably, the FW-containing stream provided in (ii) has a mass flow rate in the range of greater than 0 to 300 t / h, more preferably of 20 to 270 t / h, and more preferably of 40 to 250 t / h. Preferably, the FW-containing stream provided in (ii) has a temperature in the range of 650 to 950 °C, more preferably 750 to 900 °C, and more preferably 800 to 850 °C. Preferably, the FW-containing stream provided in (ii) has a pressure in the range of 0.5 to 7 bara, more preferably from 1 to 6 bara, more preferably from 1.5 to 5 bara. Preferably, the method according to (ii) and before (iii) further comprises Mixing the ethylbenzene-containing stream provided in (i) with the FW-containing stream S1 provided in (ii) , obtaining a reaction gas stream; wherein in (iii) the reaction gas stream is introduced into the reactor unit comprising a catalyst and is contacted with the catalyst; wherein the reaction gas stream further preferably has a mass ratio of H2O to ethylbenzene in the range of 0.8:1 to 1.3:1, preferably in the range of 0.9:1 to 1.2:1, more preferably in the range of 1:1 to 1.1:1, wherein further preferably in (iv) heat is transferred from the product gas stream obtained from (iii) to the reaction gas stream or to the reaction gas stream and an FW-containing stream S2. If the process after (ii) and before (iii) comprises mixing the ethylbenzene-containing stream provided in (i) with the FW-containing stream S1 provided in (ii), obtaining a reaction gas stream, wherein in (iii) the reaction gas stream is introduced into the reactor unit comprising a catalyst and contacted with the catalyst, it is preferred that in (iv) heat is transferred from the product gas stream obtained from (iii) to the reaction gas stream or to the reaction gas stream and an FW-containing stream S2, wherein in (iv) the reaction gas stream is further preferably heated to a temperature in the range of 450 to 540 °C, more preferably from 470 to 530 °C, more preferably from 480 to 520 °C. Preferably the reactor unit according to (iii) comprises one or more reactors, more preferably two or more reactors, more preferably two reactors, each reactor comprising the catalyst. If the reactor unit according to (iii) comprises one or more reactors, preferably two or more reactors, further preferably two reactors, wherein each reactor comprises the catalyst, it is preferred that the reactor unit comprises two or more reactors, preferably two reactors, wherein the two or more reactors are connected in series or in parallel, further preferably in series. Preferably, the catalyst included in the reactor unit according to (iii) comprises one or more Fe-containing compounds, wherein the one or more Fe-containing compounds further preferably comprise FeO, Fe2Ü3, FeO and Fe2Ü3, wherein the catalyst further preferably comprises 85 to 95 wt%, more preferably 87 to 91 wt%, of the Fe-containing compounds. Preferably, the catalyst included in the reactor unit according to (iii) comprises Cr, wherein the catalyst further preferably comprises 1.7 to 2.3 wt%, and further preferably 1.9 to 2.1 wt%, Cr. Preferably, the catalyst included in the reactor unit according to (iii) comprises KOH, wherein the catalyst further preferably comprises 7 to 11 wt%, and more preferably 8 to 10 wt%, KOH. Preferably, contact is made according to (iii) under adiabatic conditions. Preferably, contacting according to (iii) is carried out at a temperature in the range of 500 to 700 °C, more preferably in a range of 525 to 675 °C, and more preferably in a range of 550 to 650 °C. Preferably, contacting according to (iii) is carried out at a pressure in the range of 0.1 to 1.5 bara, more preferably in a range of 0.2 to 1.3 bara, and more preferably in a range of 0.25 to 1.2 bara. Preferably in (iv) heat is transferred from the product gas stream obtained from (iii) to an FW-containing stream S2, wherein the FW-containing stream S2 in (iv) is further preferably heated to a temperature in the range of 140 to 280 °C, more preferably from 160 to 260 °C, more preferably from 170 to 250 °C. Preferably, the product gas stream obtained from (iii) comprises styrene from 18 to 36 wt%, more preferably from 20 to 34 wt%, more preferably from 22 to 32 wt%. Preferably, the product gas stream obtained from (iii) comprises ethylbenzene in 12 to 34 wt%, more preferably in 14 to 32 wt%, and more preferably in 15.5 to 29 wt%. Preferably, the product gas stream obtained from (iii) comprises 40 to 65 wt%, more preferably 45 to 60 wt%, more preferably 50 to 55 wt%, water vapor. Preferably, the product gas stream obtained from (iii) comprises H2 in 0.3 to 1.3 wt%, more preferably in 0.35 to 0.8 wt%, more preferably in 0.4 to 0.6 wt%. Preferably, 90 to 100 wt%, more preferably 95 to 100 wt%, more preferably 98 to 100 wt% of the product gas stream obtained from (iii) consists of styrene, ethylbenzene, water vapor, and H2. Preferably, the product gas stream obtained from (iii) has a temperature in the range of 450 to 625 °C, more preferably 500 to 610 °C, and more preferably 540 to 590 °C. Preferably, the product gas stream obtained from (iii) has a pressure in the range of 200 to 700 mbara, more preferably from 220 to 600 mbara, and more preferably from 250 to 500 mbara. Preferably, the process after (iii) and before (iv) further compresses the product gas stream obtained from (iii). Preferably, heat is transferred in (iv) by means of one or more, more preferably two or more, more preferably two or more connected in parallel, heat exchangers. Preferably, the cooled product gas stream obtained from (iv) has a temperature in the range of 70 to 150 °C, more preferably of 85 to 140 °C, and more preferably of 90 to 120 °C. Preferably, the cooled product gas stream obtained from (iv) has a pressure in the range of 165 to 600 mbara, more preferably from 185 to 500 mbara, and more preferably from 195 to 370 mbara. Preferably, the method according to (iv) and before (v) further comprises Injection of water into the product gas stream obtained from (iii) or into the cooled product gas stream obtained from (iv), wherein the product gas stream obtained from the injection more preferably has a temperature in the range of 39 to 59 °C, more preferably 42 to 58 °C, more preferably 44 to 56 °C, wherein the product gas stream obtained from the injection more preferably has a pressure in the range of 240 to 320 mbara, more preferably 260 to 300 mbara, more preferably 270 to 290 mbara. Preferably, the method according to (iii) and prior to (vi), more preferably according to (iv) and prior to (vi), further comprises compressing the product gas stream obtained from (iii) or (iv), wherein the product gas stream obtained from (iii), (iv), or from injection according to an embodiment described herein is further preferably compressed to a pressure in the range of 500 to 800 mbara, more preferably from 550 to 750 mbara, more preferably from 580 to 680 mbara, wherein the compressed product gas stream obtained further preferably has a temperature in the range of 80 to 130 °C, more preferably from 85 to 120 °C, more preferably from 90 to 110 °C. Preferably, heat is transferred according to (vi) by means of a heat pump. Preferably, the transfer of heat according to (vi) is carried out by means of two or more heat pumps WP(n), wherein n = 1 , 2, 3, 4 is further preferably carried out by means of two heat pumps WP(1) and WP(2), wherein the two or more heat pumps are further preferably connected in parallel to each other. Preferably, the one or more heat pumps according to (vi) independently have a coefficient of performance (COP) in the range of 2.2 to 3.9, more preferably from 2.3 to 3.8, more preferably from 2.4 to 3.7. The heat transfer according to (vi) is carried out by means of one or more heat pumps, preferably by means of one heat pump WP or several heat pumps WP(n), where n = 1, 2, 3, 4. It is preferred that the heat transfer according to (vi) comprises (vi.1) Transferring heat from the product gas stream obtained from (iii) or from the cooled product gas stream obtained from (iv) to a stream WS(n) comprising a heat transfer medium, obtaining a heated stream WS(n); (vi.2) Compressing the heated current WS(n), obtaining a compressed current WS(n); (vi.3) Transferring heat from the compressed stream WS(n) obtained from (vi.2) to the FW-containing stream S3, obtaining a cooled, compressed stream WS(n) and a heated FW-containing stream S3; (vi.4) Expanding the cooled and compressed stream WS(n) obtained in (vi.3), obtaining an expanded stream WS(n); (vi.5) Returning the expanded current WS(n) obtained in (vi.4) to (vi.1 ). If the process comprises (vi.1), (vi.2), (vi.3), (vi.4), and (vi.5), it is preferred that the heat transfer medium is selected from the group consisting of but-1-ene, Z-but-2-ene, E-but-2-ene, 2-methylprop-1-ene (also referred to as iso-butene), butane, 2-methylpropane (also referred to as iso-butane), NH3, trans-1-chloro-3,3,3-trifluoropropene, (Z)-1,1,1,4,4,4-hexafluoro-2-butene, CO2, and mixtures of two or more thereof, preferably NH3. If the method comprises (vi.1), (vi.2), (vi.3), (vi.4), and (vi.5), it is preferred that the heat transfer medium is selected from classes R717, R1233, preferably R1233ZDE, R1336, preferably R1336MZZE, R600, preferably R600a, R744, and mixtures of two or more thereof. If the method comprises (vi.1 ), (vi.2), (vi.3), (vi.4), and (vi.5), it is preferred that the heat transfer medium has a boiling point in the range of -40 to 35 °C, more preferably from -37 to 5 °C, more preferably from -35 to -30 °C, and more preferably at a pressure of 1013 mbara. If the method comprises (vi.1), (vi.2), (vi.3), (vi.4), and (vi.5), it is preferred that the heat transfer medium has an evaporation temperature in the range of 37.0 to 39.0 °C, more preferably in the range of 37.9 to 38.1 °C, at an evaporation pressure in the range of 1 to 25 bara, more preferably in the range of 6 to 20 bara, more preferably in the range of 12 to 17 bara. If the method comprises (vi.1), (vi.2), (vi.3), (vi.4), and (vi.5), it is preferred that the heat transfer medium has a condensation temperature in the range of 103 to 125 °C, more preferably 111 to 117 °C, at a condensation pressure in the range of 15 to 100 bara, more preferably 30 to 90 bara, more preferably 79 to 85 bara. If the method comprises (vi.1), (vi.2), (vi.3), (vi.4), and (vi.5), and if the heat transfer medium comprises NH3, it is further preferred that the cooled and compressed stream WS(n) obtained from (vi.3) has a temperature in the range of 90 to 106 °C, more preferably 95 to 101 °C. If the method comprises (vi.1), (vi.2), (vi.3), (vi.4), and (vi.5), and if the heat transfer medium comprises NH3, it is further preferred that the cooled and compressed stream WS(n) obtained from (vi.3) has a pressure in the range of 38 to 120 bara, more preferably from 38 to 95 bara. Preferably, the FW-containing current S3 provided in (v) has a temperature in the range of 5 to 150 °C, more preferably from 5 to 120 °C, and more preferably from 15 to 105 °C. Preferably in (vi) the FW-containing current S3 is heated to a temperature in the range of 70 to 130 °C, more preferably from 75 to 125 °C, more preferably from 80 to 120 °C. Preferably, the heated FW-containing stream S3 obtained from (vi) has a pressure in the range of 0.5 to 2 bara, more preferably from 0.5 to 1.5 bara, more preferably from 0.5 to 1.3 bara. Preferably, the heated FW-containing stream S3 obtained from (vi) has a mass flow rate in the range of 20 to 70 t / h, more preferably 35 to 50 t / h, and more preferably 40 to 45 t / h. Preferably in (vii) the heated FW-containing stream S3 obtained from (vi) is compressed to a pressure in the range of 2.7 to 7 bara, more preferably from 2.7 to 6.6 bara, more preferably from 3.0 to 5.0 bara, more preferably from 3.5 to 4.5 bara. Preferably, the compressed and heated FW-containing stream S3 obtained from (vii) has a temperature in the range of 138.8 to 250 °C, more preferably from 138.8 to 200 °C, more preferably from 138.8 to 180 °C. Preferably, the compressed and heated FW-containing stream S3 obtained from (vii) has a mass flow rate in the range of 10 to 200 t / h, more preferably from 20 to 175 t / h, and more preferably from 25 to 150 t / h. Preferably, 1 to 100 wt%, more preferably 10 to 90 wt%, more preferably 20 to 80 wt%, more preferably 30 to 70 wt%, of the heated FW-containing stream S3 obtained in (vi) or of the compressed and heated FW-containing stream S3 obtained in (vii) according to (viii) are introduced into the FW-containing stream S1 provided in (ii). Preferably the method according to (viii) further comprises (ix) Separating the product gas stream obtained from (iii) or the cooled product gas stream obtained from (iv) into a liquid organic phase, a liquid aqueous phase, and a gaseous phase, the separation preferably being carried out in a separation vessel. If the process according to (ix) comprises, it is preferred that the liquid organic phase comprises styrene and optionally further organic compounds, wherein the further organic compounds are more preferably selected from the group consisting of ethylbenzene, toluene, benzene, and mixtures of two or more thereof. If the process includes (ix), it is preferred that the gaseous phase includes H2. If the method includes (ix), it is preferred that the method according to (ix) further includes (x) Distilling the liquid organic phase obtained from (ix) to obtain a styrene-containing phase, an ethylbenzene-containing phase and a phase comprising further organic compounds, wherein the further organic compounds are more preferably selected from the group consisting of ethylbenzene, toluene, benzene, and mixtures of two or more thereof, (xi) optionally recycle the ethylbenzene-containing phase into the ethylbenzene-containing stream according to (i). If the method comprises (x), preferably (x) and (xi), it is preferred that the method further comprises (x) or (xi). (xii) optional purification of the liquid aqueous phase obtained from (ix), obtaining water, (xiii) Heating the liquid aqueous phase obtained from (ix) or the purified phase obtained from (xii), yielding water vapor, (xiv) Recycling the water vapor obtained from (xiii) into the KO-containing stream S1 according to (ii). The process is preferably operated continuously. Using the method described herein, FhO-containing streams can be provided, in particular for recycling into the process itself and also for further use in other processes, wherein these KO-containing streams can be provided in various pressure and temperature ranges, preferably as steam streams. This applies in particular to the KO-containing stream S2, the KO-containing stream S3, and the compressed and heated KO-containing stream S3. With regard to these streams, it is preferred that they are in gaseous form, i.e., as water vapor. The water vapor can initially be generated in a vacuum. The resulting water vapor can be compressed to the extent required for the intended application. This is also described in the embodiments, for example, according to process step (vii) concerning the compression of S3. Compression of a gaseous KG-containing stream can be carried out using one or more compressors, preferably a cascade of compressors. Positive displacement machines and / or [other types of compressors] can be used as compressors. Turbomachinery, for example screw compressors, radial blowers, radial turbo compressors (such as geared compressors), and / or axial turbo compressors, are used. The compression process preferably includes the addition of water to spray off the steam after a compressor stage in order to increase compression efficiency. Preferably, the water is sprayed to accelerate evaporation. The compressed steam can be fed into a steam network. The compressed steam can be used in the styrene production plant or in adjacent facilities for (accompanying) heating of equipment and pipelines (e.g., for frost protection in winter), preferably at a pressure in the range of 0.5 to 2.0 barg. Alternatively, the compressed steam can be used in adjacent facilities for heating evaporators and reactors (e.g., to reduce steam consumption from the network). For example, compressing the steam to 3 barg may be sufficient. The present invention further relates to a target product that can be obtained or is attainable by a method according to the present invention. The publication “Chemical Compounds”; Issue 684; paragraphs

[1000] until

[8005] ; ISSN: 2198-4786; published on February 12, 2024, is referred to as Reference RF1, which is incorporated herein in its entirety by reference. Preferably, the target product is a product as described in Reference RF1 in paragraphs

[1000] to

[8005] described. Preferably, the method described here is furthermore a method for producing a product, preferably the target product. The conversion step for obtaining the target product preferably comprises one or more steps as described below and can be carried out by conventional methods known to a person skilled in the art. The conversion step preferably comprises one or more of the following: recycling, preferably depolymerization, gasification, pyrolysis, and / or steam cracking; and / or purification, preferably crystallization, (solvent) extraction, distillation, evaporation, hydrotreating, absorption, adsorption, and / or ion exchange treatment; and / or processing, preferably foaming, synthesis, chemical conversion, polymerization, and / or compounding; and / or shaping, preferably foaming, extrusion, and / or forming; and / or finishing, preferably coating and / or smoothing. Additionally, the one or more steps in Reference RF1 are described in the paragraphs below.

[1000] to

[8005] described in detail. The term "building block," as used here, encompasses compounds that exist in a gaseous, liquid, or solid state under standard conditions of 0°C and 0.1 MPa. Building blocks are typically used in the chemical industry to form secondary products that exhibit higher structural complexity and / or a higher molecular weight than the building block on which the secondary product is based. The building block is preferably composed of The group consisting of hydrogen, carbon monoxide, carbon dioxide, ethylene oxide, ethylene glycols, synthesis gas consisting of a mixture of hydrogen and carbon monoxide, alkanes, alkenes, alkynes, and aromatic compounds was selected. The alkanes, alkenes, alkynes, and aromatic compounds include, in particular, those with 1 to 12 carbon atoms. The term "monomer," as used here, encompasses molecules that can react with one another to form polymers by polymerization. The monomer is preferably selected from the group consisting of (meth)acrylic acid, salts of (meth)acrylic acid, in particular sodium, potassium, and zinc salts, (meth)acrolein, and (meth)acrylates. (Meth)acrylates with 1 to 22 carbon atoms are preferred, especially those with 1 to 8 carbon atoms. The terms (meth)acrylic acid, (meth)acrolein, or (meth)acrylate refer to acrylic acid, acrolein, or acrylate, respectively, and to methacrylic acid, methacrolein, or methacrylate, respectively. Furthermore, the monomer can be selected from hexamethylenediamine (HMD) and adipic acid. The building block can also be an intermediate compound. The term "intermediate compound," as used here, encompasses organic reagents used to form compounds of higher molecular complexity. The intermediate compound can be selected, for example, from the group consisting of phosgene, polyisocyanates, and propylene oxide. The polyisocyanates are, in particular, aromatic di- and polyisocyanates, preferably toluene diisocyanate (TDI) and / or diphenylmethane diisocyanate (MDI). The building block and the monomer, as well as typical conversion steps for obtaining the building block or monomer, are described in the following paragraphs.

[1000] to

[1012] The reference RF1 is described in more detail. The term "Polymer A", as used here, includes thermoplastic polymers, e.g. polyamide or thermoplastic polyurethane, thermosetting polymers, e.g. polyurethane, elastomers, e.g. polybutadiene, or a copolymer or a mixture thereof, and is further defined in the following paragraphs.

[2001] until

[2007] defined by reference RF1. The term "polymer composition A", as used here, includes all compositions containing a polymer as described above and one or more additives, e.g., reinforcing agents, colorants, modifiers and / or flame retardants, and is further specified in paragraph

[2008] defined by reference RF1. The term "polymer product A", as used here, encompasses a product containing polymer A and / or polymer composition A as described above and is further specified in the paragraphs

[2009] and

[2010] defined by reference RF1. The steps for obtaining the polymer, preferably polymer A, the polymer composition, preferably polymer composition A, or the polymer product, preferably polymer product A, are described in more detail in paragraph

[2011] described in reference RF1. The term "polymer for industrial use" includes rheological polymers, polycarboxylates, alkoxysilated polyalkylenamines, alkoxysilated polyalkylenimines, polyether-based polymers, color inhibition and dirt removal or cleaning polymers, which are described in the paragraphs

[3035] until

[3044] are defined in more detail by the reference RF1. The term "surfactant for industrial use" includes non-ionic, anionic and amphoteric surfactants for industrial use, which are described in the paragraphs

[3008] until

[3034] are defined in more detail by reference RF1. The term "descaling agents for industrial use" includes non-phosphate-based builders (NPB) and phosphonates (CoP), which are described in the paragraphs

[3001] until

[3005] are described in more detail in reference RF1. The term "biocide for industrial use" refers to a chemical compound that kills microorganisms or inhibits their growth or reproduction, as described in the paragraphs

[3006] until

[3007] further defined by the reference RF1. The term "solvents for industrial use" includes alkylamides, alkylactamides, alkyl esters, lactate esters, alkyl diesters, cyclic alkyl diesters, cyclic carbonates, aromatic aldehydes and aromatic esters, which are listed in the paragraphs

[3045] until

[3055] are defined in more detail by the reference RF1. The term "dispersants for industrial use" includes anionic and non-ionic dispersants for industrial use, which are described in the paragraphs

[3056] until

[3058] are defined in more detail by the reference RF1. The term "composition and / or formulation thereof" in relation to polymers for industrial use, surfactants for industrial use, descaling agents for industrial use and / or biocides for industrial use refers to compositions for industrial use and / or products for institutional use and / or textile and household care products and / or personal care products which are listed in paragraph

[3059] The conversion steps for the production of the polymer for industrial use, the surfactant for industrial use, the descaling agent for industrial use and / or the biocide for industrial use are defined in paragraph

[3060] Reference RF1 is defined in more detail. The conversion steps for the manufacture of the composition for industrial use or the formulation of the polymer for industrial use, the surfactant for industrial use, the descaling agent for industrial use and / or the biocide for industrial use are described in paragraph

[3061] defined in more detail by reference RF1. The term "plant protection product composition" generally refers to a composition that includes an agrochemically active component and at least one agrochemical formulation additive. Examples of plant protection product compositions include: Active ingredients and additives are listed in paragraph

[4001] The reference RF1 describes it in more detail. The plant protection product composition can be in any conventional formulation. The plant protection product compositions are manufactured using conventional methods, e.g., as described in the publications by Mollet and Grubemann, Formulation technology, Wiley VCH, Weinheim, 2001; or Knowles, New developments in crop protection product formulation, Agrow Reports DS243, T&F Informa, London, 2005. The conversion steps for the production of the agrochemically active ingredients and additives can be carried out analogously to the manufacturing steps of their analogues based on petrochemical or other precursors not obtained through recycling processes.Furthermore, conversion to compounds mentioned in the sections "Polymer" and "Cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter, other cosmetic ingredients or compositions or formulations thereof" can occur as described in those sections and the corresponding paragraphs in Reference RF1. The term "active pharmaceutical agents and / or intermediates thereof" includes substances that produce a pharmacological effect or other direct action in the diagnosis, cure, alleviation, treatment, or prevention of disease, or that affect the structure or a function of the body. Intermediates thereof are isolated products that arise during a multi-step synthesis route of an active pharmaceutical agent. The term "pharmaceutical excipients" encompasses compounds or mixtures of compounds used in compositions for various pharmaceutical applications that are not themselves substantially pharmaceutically active. Active pharmaceutical ingredients and / or intermediates thereof, as well as pharmaceutical excipients, are discussed in paragraph [number].

[5001] The reference RF1 defines in more detail. The conversion steps for the production of the active pharmaceutical ingredients and / or intermediates thereof and pharmaceutical excipients can be carried out by one or more synthesis steps and can be performed using conventional synthesis and techniques known to a person skilled in the art. The terms animal feed additives, food additives for humans and food supplements include vitamins, provitamins and active metabolites thereof, including intermediates and precursors, in particular vitamins A, B, E, D, K and their esters such as acetate, propionate, palmitate esters or alcohols thereof such as retinol or their salts, as well as any combinations thereof; tetraterpenes, in particular isoprenoids such as carotenoids and xanthophylls, including their intermediates and precursors, as well as mixtures and derivatives thereof, in particular beta-carotene, canthaxanthin, citranaxanthin, astaxanthin, zeaxanthin, lutein, lycopene, apo-carotenoids and any combinations thereof;Organic acids, in particular formic acid, propionic acid and their salts such as sodium, calcium or ammonium salts and any combinations thereof, such as, but not limited to, mixtures of formic acid and sodium formate, propionic acid and ammonium propionate, formic acid and propionic acid, formic acid and sodium formate and propionic acid, propionic acid and sodium propionate and formic acid and sodium formate; glycerides of carboxylic acids and short-chain and medium-chain fatty acids, conjugated linoleic acids such as omega-6 fatty acid (C18:2) methyl esters and 1,2-propanediol, as well as beverage stabilizers such as polyvinylpyrrolidone polymer; or polyvinylimidazole-polyvinylpyrrolidone copolymer. Animal feed additives, food additives for humans and food supplements are listed in paragraph

[5002] Reference RF1 defines in more detail. The conversion steps for the production of animal feed additives, food additives for humans, and dietary supplements can be carried out by one or more synthesis steps and can be performed using conventional synthesis and techniques known to a specialist. The term "aroma chemical and aroma composition" encompasses a volatile organic compound with a molecular weight between 70 and 250 g / mol containing a functional group with a carbon skeleton of 5 to 16 carbon atoms, including linear, branched, cyclic (e.g., with a ring size of C5-C18), bicyclic, or tricyclic aliphatic chains, and not necessarily one or more unsaturated structural elements such as double bonds, triple bonds, aromatics, or heteroaromatics. The one or more additional functional groups are preferably selected from alcohols, ethers, esters, ketones, aldehydes, acetals, carboxylic acids, nitriles, thiols, or amines. In one aspect, the aroma chemical is a terpene-based aroma chemical, selected, for example, from monoterpenes and monoterpenoids, sesquiterpenes and sesquiterpenoids, diterpenes, triterpenes, or tetraterpenes.Aroma chemicals can be combined with other aroma chemicals to form an aroma composition. Aroma chemicals and aroma compositions are discussed in paragraph [number].

[5003] The reference RF1 defines it in more detail. The conversion steps for the production of the aroma chemical and aroma composition can be carried out by one or more synthesis steps and can be performed using conventional synthesis and techniques known to a person skilled in the art. The term "aqueous polymer dispersion" includes aqueous compositions containing dispersed polymers and described in section

[6001] Reference RF1, entitled "aqueous polymer dispersion", defines the dispersed polymers in more detail. These polymers can be selected from acrylic emulsion polymers, styrene-acrylic emulsion polymers, styrene-butadiene dispersions, aqueous dispersions with composite particles, acrylate-alkyd hybrid dispersions, polyurethanes (including UV-curable polyurethanes), and polyurethane-poly(meth)acrylate hybrid polymers. The term "emulsion polymer" encompasses polymers produced by free-radical emulsion polymerization. Aqueous polyurethane dispersions are discussed in section [number missing in original text].

[6002] Reference RF1, entitled "Polyurethane dispersions", is defined in more detail. UV-curable polyurethanes are described in section

[6017] further defined in reference RF1. Polyurethane and poly(meth)acrylate hybrid polymers are described in section

[6016] further defined by the reference RF1. The term "polymeric dispersant" preferably includes polymers with a polyether-side chain, in particular polycarboxylate ether polymers and polycondensation products, which are described in paragraph

[6020] The reference RF1, titled "Polymeric Dispersant," defines the conversion (polymerization) steps for the production of aqueous polymer dispersions with Emulsion polymers are discussed in section

[6003] further defined in reference RF1 entitled "Emulsion polymerization". The compositions and uses of aqueous polymer dispersions and polymeric dispersants are further defined in the following sections of Reference RF1: Section

[6004] entitled "Uses of aqueous polymer dispersions", section

[6005] entitled "Binders for architectural and construction coatings", section

[6006] entitled "Binders for paper coating", section

[6007] with the title "Binder for fiber bonding", Section

[6008] entitled "Adhesive polymers and adhesive compositions", Section

[6015] entitled "Aqueous polyurethane dispersions for coating compositions", Section

[6016] entitled "Aqueous polyurethane-poly(meth)acrylate hybrid polymers for coating compositions", Section

[6017] entitled "Aqueous UV-curable polyurethane dispersions, their manufacture and use and compositions containing them", Section

[6018] entitled “Inorganic binder compositions with polymeric dispersants and their use”, Section

[6019] entitled "100% curable coating compositions made of UV crosslinkable poly(meth)acrylate and their use in the manufacture of pressure-sensitive self-adhesive articles". Polyisocyanates, compositions containing them, and their uses are discussed in section

[6010] further defined in reference RF1 entitled "Polyisocyanates". Hyperbranched polyester polyols and their uses are discussed in section

[6011] Reference RF1, entitled "Organically solvent-based hyperbranched polyester polyols for coating compositions," is defined in more detail. The conversion steps for producing the hyperbranched polyester polyols are described in section

[6012] further defined in reference RF1 entitled "Production of organic solvent-based hyperbranched polyester polyols". Coating compositions containing hyperbranched polyester polyols, polyisocyanates and additives, as well as substrates coated therewith, are described in section

[6013] further defined in reference RF1 entitled "Organic solvent-based two-component coating compositions with hyperbranched polyester polyols and polyisocyanates". Unsaturated polyester polyols, solvent-based coating compositions containing these unsaturated polyester polyols, and substrates for coating with these coating compositions are described in section

[6018] further defines reference RF1 entitled "Organic solvent-based coating compositions with unsaturated polyester polyols". 100% curable coating compositions are described in section

[6019] further defines the reference RF1. Polymer dispersants for inorganic binder compositions are discussed in section

[6020] further defines the reference RF1. Inorganic binder compositions with polymeric dispersants and their use are discussed in section

[6021] Reference RF1 is defined in more detail. The conversion steps for the production of the polymeric dispersants are described in section

[6020] further defines the reference RF1. The term "cosmetic surfactant", as used here, includes non-ionic, anionic, cationic and amphoteric surfactants and is defined in paragraph

[7002] Reference RF1 defines the term "emollient" as used here. It refers to a chemical compound used to protect, moisturize, and / or lubricate the skin and is further defined in paragraph [reference number missing in original text].

[7003] further defined by the reference RF1. The term "wax", as used here, includes pearlescent agents and opacifying agents and is defined in paragraph

[7004] further defined by the reference RF1. The term "cosmetic polymer", as used here, encompasses any polymer that can be used as a component of a cosmetic formulation and is defined in paragraph

[7005] further defined by the reference RF1. The term "UV filter", as used here, refers to a chemical compound that blocks or absorbs ultraviolet light and is discussed in paragraph

[7006] further defined by the reference RF1. The term "other cosmetic ingredient," as used here, encompasses any ingredient suitable for the manufacture of a cosmetic formulation. Several sources list cosmetically acceptable ingredients. For example, the Cosing database on the European Commission's website contains cosmetic ingredients, and the International Cosmetic Ingredient Dictionary and Handbook, published by the Personal Care Products Council (PCPC), lists cosmetic ingredients. The term "composition and / or formulation thereof" in relation to the cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter and / or other cosmetic ingredient refers to personal care and / or cosmetic compositions or formulations described in paragraph

[7007] The conversion steps for the production of the cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter, or other cosmetic ingredient are defined in more detail in paragraph [number].

[7008] further defined by the reference RF1. The terms "polymer B", "polymer composition B", "coating composition", "further functional composition", "film", "shaped body", "coating" and "coated substrate" are known to those skilled in the art and are used in the paragraphs

[8000] until

[8005] further defines the reference RF1. In a preferred embodiment, the target product is selected from: i) a building block or monomer; or ii) a polymer, preferably polymer A, a polymer composition, preferably polymer composition A, or a polymer product, preferably polymer product A; or iii) an industrial-grade polymer, an industrial-grade surfactant, a descaling agent, an industrial-grade biocide, an industrial-grade solvent, an industrial-grade dispersant, or a composition or formulation thereof; or iv) Agrochemical composition, agrochemical formulation aid or agrochemical active substance; or v) Active pharmaceutical ingredient or intermediate thereof, pharmaceutical excipient, feed additive, human food additive, food supplement, flavoring chemical or flavoring composition; or vi) Aqueous polymer dispersion, preferably polyurethane or polyurethane-poly(meth)acrylate hybrid polymer dispersion, emulsion, binder for paper and fiber coatings, UV-curable acrylic polymer for hot melts and coatings, polyisocyanates, hyperbranched polyester polyols, polymeric dispersant for inorganic binder compositions, unsaturated polyester polyol or 100% curable composition; or vii) Cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter, other cosmetic ingredients or compositions or formulations thereof;or viii) Polymer B, polymer composition B, coating composition, other functional composition, film, molded body, coating or coated substrate.; In a preferred embodiment, the content of styrene and converted styrene (for example, from styrene converted to a polystyrene, a styrene-butadiene graft copolymer, a styrene-butadiene block copolymer, a styrene-acrylonitrile copolymer, an acrylonitrile-butadiene-styrene copolymer, or a cross-linked polystyrene), calculated as styrene, in the target product is 1% by weight or more, preferably 2% by weight or more, more preferably 5% by weight or more, more preferably 15% by weight or more, more preferably 30% by weight or more, more preferably 40% by weight or more, more preferably 60% by weight or more, more preferably 80% by weight or more, more preferably 90% by weight or more, more preferably 95% by weight or more;and / or wherein the content of styrene and converted styrene (for example, from styrene converted to a polystyrene, a styrene-butadiene graft copolymer, a styrene-butadiene block copolymer, a styrene-acrylonitrile copolymer, an acrylonitrile-butadiene-styrene copolymer, or a cross-linked polystyrene), calculated as styrene, in the target product is 100% by weight or less, preferably 95% by weight or less, more preferably 90% by weight or less, more preferably 50% by weight or less, more preferably 25% by weight or less, more preferably 10% by weight or less; and wherein the content is preferably determined on the basis of identity preservation and / or separation and / or mass balance and / or the custody models, preferably on the basis of mass balance, preferably the International Sustainability and Carbon Certification (ISCC) Standard. In a preferred embodiment, the method, preferably according to one of the embodiments mentioned above, comprises the step: Conversion of the product of the process, namely styrene, which can be obtained or is obtained by one of the above-mentioned embodiments, in order to obtain the target product. The present invention further comprises a target product, preferably a target product according to one of the embodiments mentioned herein, which is produced or can be produced by a process that includes the use of a steam stream produced by the process described herein. The unit bara refers to absolute pressure and the unit barg to relative pressure, where 1 bar equals 10 5 Pa corresponds. The present invention is further characterized by the following embodiments, including the individual and specific combinations of embodiments indicated by the respective dependencies. It should be noted in particular that in each case where a specific number of embodiments is defined, for example in the context of a term such as "method according to one of embodiments 1 to 4", each embodiment in this set is explicitly disclosed to the person skilled in the art, which means that the formulation of this term is to be understood by the person skilled in the art as synonymous with "method according to one of embodiments 1, 2, 3 and 4".Furthermore, it is expressly pointed out that the following list of exemplary embodiments constitutes an adequate, structured part of the general description, which is directed towards preferred aspects of the present invention and thus appropriately supports, but does not constitute, the claims of the present invention. 1. Process for the production of styrene, comprising (i) Providing a stream containing ethylbenzene; (ii) Provision of a water-containing stream S1 ; (iii) Introducing the streams provided in (i) and (ii) into a reactor unit comprising a catalyst, and contacting the streams with the catalyst, obtaining a product gas stream comprising styrene; (iv) optionally transferring heat from the product gas stream obtained from (iii) to the ethylbenzene-containing stream provided in (i), to the potassium chloride-containing stream S1 provided in (ii), to a potassium chloride-containing stream S2, to the ethylbenzene-containing stream provided in (i) and to the potassium chloride-containing stream S1 provided in (ii), to the potassium chloride-containing stream S1 provided in (ii) and a potassium chloride-containing stream S2, to the ethylbenzene-containing stream provided in (i) and a potassium chloride-containing stream S2, or to the ethylbenzene-containing stream provided in (i) and the potassium chloride-containing stream S1 provided in (ii) and a potassium chloride-containing stream S2, obtaining a cooled product gas stream; (v) Provision of a KO-containing power S3; (vi) Transferring heat from the product gas stream obtained from (iii) or from the cooled product gas stream obtained from (iv) to the KO-containing stream S3, wherein the heat transfer is carried out by means of one or more heat pumps, obtaining a heated KO-containing stream S3, wherein the heated KO-containing stream S3 obtained is preferably gaseous; (vii) optionally compressing the heated FW-containing stream S3 obtained in (vi), obtaining a compressed and heated FW-containing stream S3; (viii) Introducing at least part of the heated FW-containing stream S3 obtained in (vi) or at least part of the compressed and heated FW-containing stream S3 obtained in (vii) into the FW-containing stream S1 provided in (ii). 2. The method according to embodiment 1, wherein 90 to 100 wt%, preferably 95 to 100 wt%, more preferably 99 to 100 wt%, of the ethylbenzene-containing stream provided in (i) consists of ethylbenzene. 3. The method according to embodiment 1 or 2, wherein the ethylbenzene-containing stream provided in (i) comprises H2O. 4. The method according to embodiment 3, wherein 0 to 10 wt%, preferably 0 to 5 wt%, more preferably 0 to 1 wt%, of the ethylbenzene-containing stream provided in (i) consists of H2O. 5. The method according to one of embodiments 1 to 4, wherein the ethylbenzene-containing stream provided in (i) has a mass flow rate in the range of 1 to 300 t / h, preferably from 10 to 280 t / h, more preferably from 20 to 240 t / h. 6. The method according to one of embodiments 1 to 5, wherein 90 to 100 wt%, preferably 95 to 100 wt%, more preferably 99 to 100 wt%, of the FW-containing current S1 provided in (i) consists of H2O. 7. The method according to one of embodiments 1 to 6, wherein the FhO-containing stream provided in (ii) has a mass flow rate in the range of greater than 0 to 300 t / h, preferably from 20 to 270 t / h, more preferably from 40 to 250 t / h. 8. The method according to one of embodiments 1 to 7, wherein the FhO-containing stream provided in (ii) has a temperature in the range of 650 to 950 °C, preferably 750 to 900 °C, more preferably 800 to 850 °C. 9. The method according to one of embodiments 1 to 8, wherein the FhO-containing stream provided in (ii) has a pressure in the range of 0.5 to 7 bara, preferably 1 to 6 bara, more preferably 1.5 to 5 bara. 10. The method according to one of embodiments 1 to 9, further comprising (ii) and before (iii) Mixing the ethylbenzene-containing stream provided in (i) with the FW-containing stream S1 provided in (ii) to obtain a reaction gas stream; wherein in (iii) the reaction gas stream is introduced into the reactor unit comprising a catalyst and contacted with the catalyst; wherein the reaction gas stream preferably has a mass ratio of H2O to ethylbenzene in the range of 0.8:1 to 1.3:1, preferably in the range of 0.9:1 to 1.2:1, further preferably in the range of 1:1 to 1.1:1, wherein preferably in (iv) heat is transferred from the product gas stream obtained from (iii) to the reaction gas stream or to the reaction gas stream and an FW-containing stream S2. 11. The method according to embodiment 10, wherein in (iv) heat is transferred from the product gas stream obtained from (iii) to the reaction gas stream or to the reaction gas stream and an FW-containing stream S2, and wherein the reaction gas stream in (iv) is preferably heated to a temperature in the range of 450 to 540 °C, preferably from 470 to 530 °C, more preferably from 480 to 520 °C. 12. The method according to one of embodiments 1 to 11, wherein the reactor unit according to (iii) comprises one or more reactors, preferably two or more reactors, more preferably two reactors, each reactor comprising the catalyst. 13. The method according to embodiment 12, wherein the reactor unit comprises two or more reactors, preferably two reactors, wherein the two or more reactors are connected in series or in parallel, more preferably in series. 14. The method according to one of embodiments 1 to 13, wherein the contacting according to (iii) takes place under adiabatic conditions. 15. The method according to one of embodiments 1 to 14, wherein the contacting according to (iii) is carried out at a temperature in the range of 500 to 700 °C, preferably in a range of 525 to 675 °C, more preferably in a range of 550 to 650 °C. 16. The method according to one of embodiments 1 to 15, wherein the contacting according to (iii) is carried out at a pressure in the range of 0.1 to 1.5 bara, preferably in a range of 0.2 to 1.3 bara, more preferably in a range of 0.25 to 1.2 bara. 17. The method according to one of embodiments 1 to 16, wherein in (iv) heat is transferred from the product gas stream obtained from (iii) to an FW-containing stream S2, and wherein the FhO-containing stream S2 in (iv) is preferably heated to a temperature in the range of 140 to 280 °C, preferably from 160 to 260 °C, more preferably from 170 to 250 °C. 18. The method according to one of embodiments 1 to 17, wherein the product gas stream obtained from (iii) comprises styrene from 18 to 36 wt%, preferably from 20 to 34 wt%, more preferably from 22 to 32 wt%. 19. The method according to one of embodiments 1 to 18, wherein the product gas stream obtained from (iii) comprises ethylbenzene from 12 to 34 wt%, preferably from 14 to 32 wt%, more preferably from 15.5 to 29 wt%. 20. The method according to one of embodiments 1 to 19, wherein the product gas stream obtained from (iii) comprises 40 to 65 wt%, preferably 45 to 60 wt%, more preferably 50 to 55 wt% water vapor. 21. The method according to one of embodiments 1 to 20, wherein the product gas stream obtained from (iii) comprises H2 from 0.3 to 1.3 wt%, preferably from 0.35 to 0.8 wt%, more preferably from 0.4 to 0.6 wt%. 22. The method according to one of embodiments 1 to 21, wherein 90 to 100 wt%, preferably 95 to 100 wt%, more preferably 98 to 100 wt%, of the product gas stream obtained from (iii) consist of styrene, ethylbenzene, water vapor, and H2. 23. The method according to one of embodiments 1 to 22, wherein the product gas stream obtained from (iii) has a temperature in the range of 450 to 625 °C, preferably 500 to 610 °C, more preferably 540 to 590 °C. 24. The method according to one of embodiments 1 to 23, wherein the product gas stream obtained from (iii) has a pressure in the range of 200 to 700 mbara, preferably 220 to 600 mbara, more preferably 250 to 500 mbara. 25. The method according to one of embodiments 1 to 24, further comprising (iii) and before (iv) Compressing the product gas stream obtained from (iii). 26. The method according to one of embodiments 1 to 25, wherein the transfer of heat in (iv) is carried out by means of one or more, preferably two or more, more preferably two or more connected in parallel, heat exchangers. 27. The method according to one of embodiments 1 to 26, wherein the cooled product gas stream obtained from (iv) has a temperature in the range of 70 to 150 °C, preferably 85 to 140 °C, more preferably 90 to 120 °C. 28. The method according to one of embodiments 1 to 27, wherein the cooled product gas stream obtained from (iv) has a pressure in the range of 165 to 600 mbara, preferably 185 to 500 mbara, more preferably 195 to 370 mbara. 29. The method according to one of embodiments 1 to 28, further comprising (iv) and (v) Injection of water into the product gas stream obtained from (iii) or into the cooled product gas stream obtained from (iv), wherein the product gas stream obtained from the injection preferably has a temperature in the range of 39 to 59 °C, more preferably 42 to 58 °C, more preferably 44 to 56 °C, wherein the product gas stream obtained from the injection further preferably has a pressure in the range of 240 to 320 mbara, more preferably 260 to 300 mbara, more preferably 270 to 290 mbara. 30. The method according to one of embodiments 1 to 29, further comprising (iii) and before (vi), preferably according to (iv) and before (vi) Compressing the product gas stream obtained from (iii) or (iv), wherein the product gas stream obtained from (iii), (iv), or from injection according to embodiment 29 is preferably compressed to a pressure in the range of 500 to 800 mbara, more preferably from 550 to 750 mbara, more preferably from 580 to 680 mbara, wherein the compressed product gas stream obtained preferably has a temperature in the range of 80 to 130 °C, more preferably from 85 to 120 °C, more preferably from 90 to 110 °C. 31. The method according to one of embodiments 1 to 30, wherein the transfer of heat according to (vi) is carried out by means of a heat pump. 32. The method according to one of embodiments 1 to 31, wherein the transfer of heat according to (vi) is carried out by means of two or more heat pumps WP(n), wherein n = 1 , 2, 3, 4, ..., preferably by means of two heat pumps WP(1) and WP(2), wherein the two or more heat pumps are preferably connected in parallel to each other. 33. The method according to one of embodiments 1 to 32, wherein the one or more heat pumps according to (vi) independently have a coefficient of performance (COP) in the range of 2.2 to 3.9, preferably 2.3 to 3.8, more preferably 2.4 to 3.7. 34. The method according to one of embodiments 1 to 33, comprising the transfer of heat according to (vi) by means of a heat pump WP or several heat pumps WP(n), where n = 1, 2, 3, 4 (vi.1) Transferring heat from the product gas stream obtained from (iii) or from the cooled product gas stream obtained from (iv) to a stream WS(n) comprising a heat transfer medium, obtaining a heated stream WS(n); (vi.2) Compressing the heated current WS(n), obtaining a compressed current WS(n); (vi.3) Transferring heat from the compressed stream WS(n) obtained from (vi.2) to the FW-containing stream S3, obtaining a cooled, compressed stream WS(n) and a heated FW-containing stream S3; (vi.4) Expanding the cooled and compressed stream WS(n) obtained in (vi.3), obtaining an expanded stream WS(n); (vi.5) Returning the expanded current WS(n) obtained in (vi.4) to (vi.1 ). 35. The method according to embodiment 34, wherein the heat transfer medium is selected from the group consisting of but-1-ene, Z-but-2-ene, E-but-2-ene, 2-methylprop-1-ene (also referred to as iso-butene), butane, 2-methylpropane (also referred to as iso-butane), NH3, trans-1-chloro-3,3,3-trifluoropropene, (Z)-1,1,1,4,4,4-hexafluoro-2-butene, CO2, and mixtures of two or more thereof, preferably NH3. 36. The method according to embodiment 34 or 35, wherein the heat transfer medium comprises NH3, is preferred, and wherein the cooled and compressed stream WS(n) obtained from (vi.3) has a temperature in the range of 90 to 106 °C, preferably 95 to 101 °C. 37. The method according to embodiment 34 or 35, wherein the heat transfer medium comprises NH3, is preferred, and wherein the cooled and compressed stream WS(n) obtained from (vi.3) has a pressure in the range of 38 to 120 bara, preferably from 38 to 95 bara. 38. The method according to one of embodiments 1 to 37, wherein the heat transfer medium is selected from classes R717, R1233, preferably R1233ZDE, R1336, preferably R1336MZZE, R600, preferably R600a, R744, and mixtures of two or more thereof. 39. The method according to one of embodiments 1 to 38, wherein the heat transfer medium has a boiling point in the range of -40 to 35 °C, preferably from -37 to 5 °C, more preferably from -35 to -30 °C, preferably at a pressure of 1013 mbara. 40. The method according to one of embodiments 1 to 39, wherein the heat transfer medium has an evaporation temperature in the range of 37.0 to 39.0 °C, preferably from 37.9 to 38.1 °C, at an evaporation pressure in the range of 1 to 25 bara, preferably in the range of 6 to 20 bara, more preferably in the range of 12 to 17 bara. 41. The method according to one of embodiments 1 to 40, wherein the heat transfer medium has a condensation temperature in the range of 103 to 125 °C, preferably 111 to 117 °C, at a condensation pressure in the range of 15 to 100 bara, preferably in the range of 30 to 90 bara, more preferably in the range of 79 to 85 bara. 42. The method according to one of embodiments 1 to 41, wherein the FhO-containing current S3 provided in (v) has a temperature in the range of 5 to 150 °C, preferably 5 to 120 °C, more preferably 15 to 105 °C. 43. The method according to one of embodiments 1 to 42, wherein in (vi) the FhO-containing stream S3 is heated to a temperature in the range of 70 to 130 °C, preferably 75 to 125 °C, more preferably 80 to 120 °C. 44. The method according to one of embodiments 1 to 43, wherein the heated FhO-containing stream S3 obtained from (vi) has a pressure in the range of 0.5 to 2 bara, preferably 0.5 to 1.5 bara, more preferably 0.5 to 1.3 bara. 45. The method according to one of embodiments 1 to 44, wherein the heated FhO-containing stream S3 obtained from (vi) has a mass flow rate in the range of 20 to 70 t / h, preferably 35 to 50 t / h, more preferably 40 to 45 t / h. 46. ​​The method according to one of embodiments 1 to 45, wherein in (vii) the heated FhO-containing stream S3 obtained from (vi) is compressed to a pressure in the range of 2.7 to 7 bara, preferably 2.7 to 6.6 bara, more preferably 3.0 to 5.0 bara, more preferably 3.5 to 4.5 bara. 47. The method according to one of embodiments 1 to 46, wherein the compressed and heated FhO-containing stream S3 obtained from (vii) has a temperature in the range of 138.8 to 250 °C, preferably 138.8 to 200 °C, more preferably 138.8 to 180 °C. 48. The method according to one of embodiments 1 to 47, wherein the compressed and heated FhO-containing stream S3 obtained from (vii) has a mass flow rate in the range of 10 to 200 t / h, preferably from 20 to 175 t / h, more preferably from 25 to 150 t / h. 49. The method according to one of embodiments 1 to 48, wherein 1 to 100 wt%, preferably 10 to 90 wt%, more preferably 20 to 80 wt%, more preferably 30 to 70 wt%, of the heated FhO-containing stream S3 obtained in (vi) or of the compressed and heated FW-containing stream S3 obtained in (vii) according to (viii) are introduced into the FW-containing stream S1 provided in (ii). 50. The method according to one of embodiments 1 to 49, further comprising according to (viii) (ix) separating the product gas stream obtained from (iii) or the cooled product gas stream obtained from (iv) into a liquid organic phase, a liquid aqueous phase, and a gaseous phase, wherein the separation preferably takes place in a separation vessel. 51. The process according to embodiment 50, wherein the liquid organic phase comprises styrene and optionally further organic compounds, wherein the further organic compounds are preferably selected from the group consisting of ethylbenzene, toluene, benzene, and mixtures of two or more thereof. 52. The method according to embodiment 50 or 51, wherein the gaseous phase comprises H2. 53. The method according to one of embodiments 50 to 52, further comprising according to (ix) (x) Distilling the liquid organic phase obtained from (ix) to obtain a styrene-containing phase, an ethylbenzene-containing phase and a phase comprising further organic compounds, wherein the further organic compounds are preferably selected from the group consisting of ethylbenzene, toluene, benzene, and mixtures of two or more thereof, (xi) optionally recycle the ethylbenzene-containing phase into the ethylbenzene-containing stream according to (i). 54. The method according to embodiment 53, further comprising (x) or (xi) (xii) optional purification of the liquid aqueous phase obtained from (ix), obtaining water, (xiii) Heating the liquid aqueous phase obtained from (ix) or the purified phase obtained from (xii), yielding water vapor, (xiv) Recycling the water vapor obtained from (xiii) into the l-hO-containing stream S1 according to (ii). 55. The method according to one of embodiments 1 to 54, wherein the method is operated continuously. The present invention is further illustrated by the following reference examples, examples and comparative examples. EXAMPLES Comparative example 1: Process for the production of styrene A process for the production of styrene based on the adiabatic dehydrogenation of ethylbenzene to styrene was simulated. A simplified representation of the underlying plant can be found in Figure 1. The plant had a capacity of approximately 64 t / h of styrene. The plant comprised a steam heater for preheating the reactant stream of ethylbenzene, two reactors connected in series, each containing a catalyst suitable for the reaction, a heat exchanger that could be used, for example, to generate or preheat a steam-containing stream, and downstream components including a condenser to cool the resulting product stream for further processing. A reactant stream consisting of ethylbenzene, diluted with steam, was fed into the first of the two reactors. The inlet temperature to the first reactor was between 600 and 650 °C. The mass ratio of steam to ethylbenzene was approximately 1:1 to 1.1:1. The steam added before the first reactor was heated to a temperature above 800 °C in a steam heater. The reaction in the first reactor cooled the mixture to a temperature of approximately 550 °C, and the conversion of ethylbenzene reached approximately 40% at the end of the first reactor. To achieve a higher conversion, the mixture was reheated to approximately 600 to 650 °C in a heat exchanger heated with superheated steam before entering the second reactor. Through the reaction in the second reactor, the mixture cooled to a temperature of approximately 560 °C, and the conversion of ethylbenzene reached 60 to 70% at the exit of the second reactor. The reaction mixture exiting the reaction zone, consisting primarily of water vapor, styrene, unreacted ethylbenzene, and byproducts, was cooled to a temperature of 100 to 120 °C by heat exchangers downstream of the reactors. In these heat exchangers, ethylbenzene was vaporized, and ethylbenzene and water vapor were heated. Additionally, steam was generated from preheated water in one heat exchanger and fed into an external network. The reaction mixture, cooled to approximately 100 to 120 °C, was condensed and further cooled in a downstream condenser using cooling water or air, whereby the heat released in the process was lost for economic use. The condensed mass stream then entered a separation vessel where water, liquid organic phase (dehydrogenation mixture), and gas (dehydrogenation gas, consisting primarily of hydrogen) were separated. After purification, the water could be returned to the process. The organic phase contained styrene, unreacted ethylbenzene, and smaller amounts of toluene, benzene, and other compounds. This mixture was separated in a downstream distillation. The unreacted ethylbenzene was returned to the process. The dehydrogenation process according to comparative example 1, with a production rate of approximately 64 t / h of styrene, required 44 t / h of steam at 1.7 bar and 90 t / h of steam at 4 bar. In the heat exchanger downstream of the reactors, 37 t / h of steam could be generated through heat recovery. Thus, the dehydrogenation process required a net steam consumption of 97 t / h. An additional 52 t / h of steam at 4 bar was required for distillation to separate the organic phase (dehydrogenation mixture). Therefore, the total steam consumption for dehydrogenation and distillation was 149 t / h. The CO₂ footprint of the steam (scope 1, 2, and 3) was approximately 0.21 kg CO₂. eq / kg(steam). Scope 1 and 2 include emissions originating from the styrene production plant and its energy supply, while scope 3 includes emissions not directly related to the plant but arising from the processing of raw materials and products in other plants. Thus, with a production volume of 64 t / h of styrene, the CC>2 footprint of the styrene generated by steam consumption was approximately 0.5 kg CO2- eq / kg(styrene). The CC>2 footprint of styrene was approximately 0.6 kg CO2- eq / kg(styrene). Example 2: Process for the production of styrene according to the present invention A process for the production of styrene based on the adiabatic dehydrogenation of ethylbenzene to styrene was simulated. A simplified representation of the plant is shown in Figure 2. The plant had a capacity of approximately 64 t / h of styrene. The plant comprised a steam heater for preheating the feed stream of ethylbenzene, two reactors connected in series, each containing a catalyst suitable for the reaction, a heat exchanger that could be used to generate or preheat a steam-containing stream, for example, a heat pump, and downstream components including a condenser to cool the resulting product stream for further processing. A reactant stream consisting of ethylbenzene, diluted with steam, was fed into the first of the two reactors. The inlet temperature to the first reactor was between 600 and 650 °C. The mass ratio of steam to ethylbenzene was approximately 1:1 to 1.1:1. The steam added before the first reactor was heated to a temperature above 800 °C in a steam heater. The reaction in the first reactor cooled the mixture to a temperature of approximately 550 °C, and the conversion of ethylbenzene reached approximately 40% at the end of the first reactor. To achieve a higher conversion, the mixture was reheated to approximately 600 to 650 °C in a heat exchanger heated with superheated steam before entering the second reactor. Through the reaction in the second reactor, the mixture cooled to a temperature of approximately 560 °C, and the conversion of ethylbenzene reached 60 to 70% at the exit of the second reactor. The reaction mixture exiting the reaction zone, consisting primarily of water vapor, styrene, unreacted ethylbenzene, and byproducts, was cooled to a temperature of 100 to 120 °C by heat exchangers downstream of the reactors. Heat recovery took place in a heat exchanger consisting of three chambers. In the first chamber, the water-ethylbenzene mixture was superheated to 480 to 520 °C; in the second chamber, the feedwater for the high-pressure steam (40 bar) was evaporated at 255 to 265 °C; and in the third chamber, the water-ethylbenzene mixture was heated to 170 to 250 °C. The vapors exiting the heat exchanger are further cooled to 63 °C. The reaction mixture, cooled to 63 °C, is then used as a heat source to transfer heat to a water-containing stream via a heat pump. NH3 is used as the heat transfer fluid (also known as a refrigerant) in the heat pump. It was possible to utilize the majority of the available thermal heat with the heat pump. Alternatively, it would also be possible, for example with a smaller heat pump, to utilize only a portion, or to produce the desired amount of steam by using multiple heat pumps. If, for example, only a portion of the heat were used in the heat pump, the further cooling of the reaction mixture could take place in the downstream condenser. a) Integration of a heat pump In a first embodiment, a heat pump was integrated with the following operating data: Steam production of the heat pump: 74 t / h, Power consumption of heat pump and compressor: 21 MW COP 2.8. As shown in comparative example 1 above, the amount of steam required for dehydration and distillation is 97 t / h + 52 t / h = 149 t / h. The CO2 footprint of the steam (scope 1 and 2) is approximately 0.21 kg CO2- eq / kg(steam). The heat pump was able to generate 74 t / h of steam. This reduced the demand to 75 t / h. Thus, with a production volume of 64 t / h of styrene, the CO2 footprint of the styrene generated by steam consumption was approximately 0.25 kg CO2- eq / kg(styrene). Assuming the heat pump was powered by green electricity, the scope 1 emissions were reduced by approximately 50% compared to the reference example. b) Integration of two heat pumps In a second embodiment, in addition to the first embodiment according to a), a further heat pump was integrated with the following operating data: Steam production of the second heat pump: 93 t / h, Power consumption of second heat pump and compressor: 29 MW, COP 2.6. As shown in comparative example 1 above, the amount of steam required for dehydration and distillation is 97 t / h + 52 t / h = 149 t / h. The CO2 footprint of the steam (scope 1 and 2) is approximately 0.21 kg CO2- eq / kg(steam). The two heat pumps generated 167 t / h of steam. This reduced the demand to zero, and an additional 18 t / h of steam could be generated and fed into the plant's internal steam network. Assuming the heat pump was powered by green electricity, the scope 1 emissions were reduced by approximately 93% compared to the reference example. Description of the illustrations Figure 1: shows a simplified representation of a plant for the production of styrene, in particular comprising a furnace, two reactors connected in series, a heat exchanger, and a condenser. Figure 2: shows a simplified representation of a plant for the production of styrene according to the present invention, the plant in particular comprising a furnace, two reactors connected in series, a heat exchanger, a heat pump, and a condenser. List of reference symbols 51 Ethylbenzene-containing current 52 H2O-containing electricity 53 H2O-containing electricity A1 Steam superheater / Oven A2 first reactor A3 second reactor A4 inlet superheater A5 steam generator A6 Inlet evaporator A7 Condenser / Air Cooler A8 Gas / Liquid Separator A9 Liquid / Liquid Separator A10 Dehydration gas compressor A11 Condenser / Air cooler for aromatic recovery Cited literature - DE 3147323 A1 - US 4,695,664 - US 2012 / 149960 A1 - EP 2651859 B1

Claims

Claims 1. Process for the production of styrene, comprising (I) Providing a stream containing ethylbenzene; (ii) Providing a water-containing stream S1 ; (iii) Introducing the streams provided in (i) and (ii) into a reactor unit comprising a catalyst, and contacting the streams with the catalyst, obtaining a product gas stream comprising styrene; (iv) optionally transferring heat from the product gas stream obtained from (iii) to the ethylbenzene-containing stream provided in (i), to the potassium chloride-containing stream S1 provided in (ii), to a potassium chloride-containing stream S2, to the ethylbenzene-containing stream provided in (i) and to the potassium chloride-containing stream S1 provided in (ii), to the potassium chloride-containing stream S1 provided in (ii) and a potassium chloride-containing stream S2, to the ethylbenzene-containing stream provided in (i) and a potassium chloride-containing stream S2, or to the ethylbenzene-containing stream provided in (i) and the potassium chloride-containing stream S1 provided in (ii) and a potassium chloride-containing stream S2, obtaining a cooled product gas stream; (v) Provision of a KO-containing power S3; (vi) Transferring heat from the product gas stream obtained from (iii) or from the cooled product gas stream obtained from (iv) to the KO-containing stream S3, wherein the heat transfer is carried out by means of one or more heat pumps, obtaining a heated KO-containing stream S3; (vii) optionally compressing the heated KO-containing stream S3 obtained in (vi), obtaining a compressed and heated KO-containing stream S3; (viii) Introducing at least part of the heated KO-containing stream S3 obtained in (vi) or at least part of the compressed and heated KO-containing stream S3 obtained in (vii) into the KO-containing stream S1 provided in (ii).

2. The method according to claim 1, wherein 90 to 100 wt% of the ethylbenzene-containing stream provided in (i) consists of ethylbenzene.

3. The method according to claim 1 or 2, further comprising, after (ii) and before (iii), mixing the ethylbenzene-containing stream provided in (i) with the KO-containing stream S1 provided in (ii), obtaining a reaction gas stream; wherein, in (iii), the reaction gas stream is introduced into the reactor unit comprising a catalyst and contacted with the catalyst.

4. The method according to any one of claims 1 to 3, wherein the reactor unit according to (iii) comprises one or more reactors, each reactor comprising the catalyst.

5. The method according to any one of claims 1 to 4, wherein the product gas stream obtained from (iii) comprises 18 to 36 wt% styrene.

6. The method according to any one of claims 1 to 5, wherein the product gas stream obtained from (iii) comprises 40 to 65 wt% water vapor.

7. The method according to any one of claims 1 to 6, wherein the product gas stream obtained from (iii) comprises 0.3 to 1.3 wt% H2.

8. The method according to any one of claims 1 to 7, wherein the product gas stream obtained from (iii) has a pressure in the range of 200 to 700 mbara.

9. The method according to any one of claims 1 to 8, wherein the transfer of heat in (iv) is carried out by means of one or more heat exchangers.

10. The method according to any one of claims 1 to 9, wherein the transfer of heat according to (vi) is carried out by means of a heat pump.

11. The method according to any one of claims 1 to 10, wherein the transfer of heat according to (vi) by means of a heat pump WP or several heat pumps WP(n), wherein n = 1, 2, 3, 4 includes (vi.1) Transferring heat from the product gas stream obtained from (iii) or from the cooled product gas stream obtained from (iv) to a stream WS(n) comprising a heat transfer medium, obtaining a heated stream WS(n); (vi.2) Compressing the heated current WS(n), obtaining a compressed current WS(n); (vi.3) Transferring heat from the compressed stream WS(n) obtained from (vi.2) to the l-hO-containing stream S3, obtaining a cooled, compressed stream WS(n) and a heated l-hO-containing stream S3; (vi.4) Expanding the cooled and compressed stream WS(n) obtained in (vi.3), obtaining an expanded stream WS(n); (vi.5) Returning the expanded current WS(n) obtained in (vi.4) to (vi.1).

12. The method according to claim 11, wherein the heat transfer medium is selected from the group consisting of but-1-ene, Z-but-2-ene, E-but-2-ene, 2-methylprop-1-ene, butane, 2-methylpropane, NH3, trans-1-chloro-3,3,3-trifluoropropene, (Z)-1,1,1,4,4,4-hexafluoro-2-butene, CO2, and mixtures of two or more thereof.

13. The method according to claim 11, wherein the heat transfer medium is selected from classes R717, R1233, R1336, R600, R744, and mixtures of two or more thereof.

14. The method according to any one of claims 1 to 13, wherein in (vi) the FhO-containing current S3 is heated to a temperature in the range of 70 to 130 °C.

15. Method for producing a target product by converting the styrene that can be obtained or has been obtained according to any one of claims 1 to 14.

Images