Sustainable preparation of hexamethylene diisocyanate for polyurethane production

Abstract

The present invention relates to a method for preparing a hexamethylene diisocyanate as described in claim 1, and a method for preparing a polyurethane from a hexamethylene diisocyanate, wherein methanol is used in the method as a raw material for constructing the hexamethylene moiety of the hexamethylene diisocyanate.

Description

[Technical Field]

[0001] The present invention relates to a method for producing hexamethylene diisocyanate for the synthesis of polyurethane, a method for producing polyurethane from hexamethylene diisocyanate obtained according to the method, and a multiple component system for producing hexamethylene diisocyanate according to the method. [Background technology]

[0002] The industrial production of hexamethylene diisocyanate (HDI, also known as hexane-1,6-diyldiisocyanate or 1,6-diisocyanatehexane) has historically relied primarily on the use of fossil raw materials, such as synthesis gas and petroleum-based aromatic compounds derived from natural gas. The systematic use of renewable raw materials and / or by-products from waste for the production of materials such as hexamethylene diisocyanate is a goal for providing sustainable plastics, such as polyurethane and materials derived therefrom.

[0003] The use of energy from renewable energy sources for the industrial production of chemical raw materials, such as hexamethylene diisocyanate, is also desirable. [Overview of the project] [Problems that the invention aims to solve]

[0004] Therefore, an object of the present invention was to provide a more sustainable method for producing hexamethylene diisocyanate on an industrial scale that enables the use of renewable raw materials. A further object of the present invention was also to provide a method for producing hexamethylene diisocyanate that enables the achievement of low-emission hexamethylene diisocyanate for the production of polyurethane, despite the possible fluctuations in the availability of renewable energy. "Renewable energy" is understood by those skilled in the art to mean energy from inexhaustible energy sources, such as wind, hydro, bioenergy (e.g., the conversion of biogas or biomass into electricity) or solar power.

[0005] The “sustainability” of a method is understood by those skilled in the art in accordance with the definition of sustainability (sustainable development) created by the United Nations in the Brundtland Report of the World Commission on Environment and Development, which means that the current implementation of a method makes the smallest possible contribution, or no contribution at all, to the ability of future generations to meet their own needs, in particular regarding the use of resources such as fossil fuels, and especially regarding the preservation of living spaces, such as the protection of the Earth’s atmosphere. Therefore, the object of the present invention is to make the production of hexamethylene diisocyanate and polyurethane produced therefrom more sustainable than production methods known from the prior art. The contribution of the production of hexamethylene diisocyanate and polyurethane to reducing the satisfaction of the needs of future generations should be reduced or avoided. [Means for solving the problem]

[0006] Therefore, the first subject of the present invention is a method for producing hexamethylene diisocyanate for the production of polyurethane, comprising at least the following steps: a) Providing hexamethylenediamine, a method product of a method comprising at least the following steps: i) Providing methanol, which is a method product of a method comprising at least the following steps: i-1) Providing a method for at least partial reduction of CO2 to CO as a product and / or a method for at least partial oxidation of an organic material to CO as a product, wherein at least one organic material is selected from at least one organic, solid compound, methane from a biosource or a mixture thereof; i-2) Conversion of the provided carbon monoxide to methanol; ii) Synthesis of propene from methanol provided above by at least the following steps: ii-1) Conversion of the methanol previously provided to give a product mixture containing dimethyl ether, water, and methanol; ii-2) Conversion of the product mixture to propene in each case from a starting material containing dimethyl ether, water, and methanol by contact with a catalyst, preferably at least one zeolite compound as a catalyst, at a temperature exceeding 200°C; (iii) Synthesis of acrylonitrile from propene by at least the following steps: iii-1) Providing ammonia as a method product of a method comprising at least the following steps: iii-1-1) Preferably providing hydrogen gas as a product of water electrolysis using electrical energy generated from renewable energy; iii-1-2) Reaction of the provided hydrogen gas with gaseous nitrogen to yield ammonia; iii-2) Reaction of the propene with the provided ammonia to yield acrylonitrile; iv) Synthesis of adiponitrile from acrylonitrile by at least the following steps: Introducing a mixture containing water, the acrylonitrile, and at least one electrolyte salt into the cathode space of an electrolytic cell, and bringing the mixture into contact with the cathode to which an electric current is applied; Cathodic hydrodimerization of acrylonitrile to form an adiponitrile-containing product mixture; Discharge of the adiponitrile-containing product mixture from the cathode space of the electrolytic cell and optional purification of the adiponitrile; v) Synthesis of hexamethylenediamine from adiponitrile by at least the following steps: Preferably, providing hydrogen gas as a product of electrolysis using electrical energy generated from renewable energy; Hydrogenation of the adiponitrile with hydrogen gas to yield hexamethylenediamine; b) Production of phosgene by at least the following method steps: i) A method for at least partial reduction of CO2 to CO, and / or a method for at least partial oxidation of an organic material to CO, providing carbon monoxide as the product, wherein at least one organic material is selected from at least one organic, solid compound, organic, liquid monohydroxyalkyl compound, methane from a biosource, or a mixture thereof; ii) Reaction of carbon monoxide from step i) with chlorine to yield phosgene; c) Reaction of the provided hexamethylenediamine with phosgene to give hexamethylene diisocyanate. This method includes [something]. [Modes for carrying out the invention]

[0007] According to the present invention, the “catalyzed reaction” or “catalytic reaction” is carried out using a catalyst that catalyzes the formation of a product from at least one reactant (e.g., carbon dioxide or methanol) by reducing the energy required and / or increasing the yield of the product by improving selectivity, compared to the same reaction under the same reaction conditions but in the absence of the catalyst. For example, the conversion according to step a)ii-2) is a catalytic reaction of the starting materials to give propene.

[0008] According to the present invention, a material or chemical compound is organic if the material / chemical compound contains at least one covalent carbon-hydrogen bond.

[0009] A substance / material is defined as a solid if the substance is in solid form at 25 °C and 1013 mbar. A substance / material is defined as a liquid if the substance is in liquid form at 25 °C and 1013 mbar.

[0010] In step a) of the process according to the invention, hexamethylenediamine (also known as 1,6-diaminohexane or hexane-1,6-diamine) is provided. For the provision of hexamethylenediamine, according to the invention, it is sufficient if the hexamethylenediamine provided is the actual process product of at least steps i), ii), iii), iv) and v) described in a). This means that for carrying out the step of providing hexamethylenediamine, it is sufficient to simply take out the hexamethylenediamine produced in the described manner from a storage container or a supply conduit in the context of delivery as a raw material for supplying hexamethylenediamine to at least step c) of the process according to the invention. In this case, the hexamethylenediamine manufacturer, as the implementer of the process according to the invention, does not itself carry out steps i) and ii) for producing the hexamethylenediamine described in a) of the process according to the invention, but rather merely ensures that the hexamethylenediamine provided has been produced by application of at least steps i) and ii) described in a) and is thus its actual process product.

[0011] According to the invention, for the provision of hexamethylenediamine, it is likewise possible that at least steps i) to v) for producing the hexamethylenediamine described in a) are carried out by the hexamethylenediisocyanate manufacturer as essential steps of the process according to the invention for producing hexamethylenediisocyanate, and the hexamethylenediamine obtained thereby is supplied to at least step c) of the process according to the invention, optionally after intermediate storage in a storage container.

[0012] In each case, the availability of a specific hexamethylenediamine by a hexamethylene diisocyanate manufacturer, i.e., the possibility of supply or in-house production, also applies to the following embodiments of steps i) to v) described in a).

[0013] Step i) listed in a) of the method according to the invention comprises at least the following steps: i-1) The conversion of CO to methanol, where CO is a product of at least partial reduction of CO2 to CO and / or a product of at least partial oxidation of an organic material to CO, and at least one organic material is selected from at least one organic, solid compound, methane from a biological source or a mixture thereof, the conversion requires the provision of methanol which is the actual product of the method of the method in question.

[0014] According to the invention, for the provision of methanol, it is sufficient if the methanol is the actual product of the reaction described in at least i-1), which reaction utilizes carbon monoxide (carbon monoxide is also denoted as CO) which is the actual product of a particular method. This means that to carry out the step of providing methanol, it is sufficient to simply remove the methanol produced in the described manner from a storage container or from a supply conduit in the context of delivery as a raw material. In this case, the hexamethylene diisocyanate manufacturer as the implementer of the method according to the invention, or the supplier of the hexamethylenediamine provided for the method according to the invention, does not itself carry out the reaction to produce methanol, but rather only ensures that the methanol provided for the provision of hexamethylenediamine is produced by at least the application of the said step i-1) and is thus its actual product.

[0015] According to the present invention, with respect to the provision of methanol, at least the aforementioned conversion for producing methanol may be carried out by a hexamethylene diisocyanate producer or a supplier of the provided hexamethylenediamine as an integral step of the method according to the present invention for producing hexamethylene diisocyanate, and the methanol thereby obtained may optionally be supplied to the synthesis of hexamethylenediamine provided under step a) of the method, while carrying out at least steps ii-1), ii-2), iii), iv), and v) after intermediate storage in a storage container.

[0016] In each case, the possibility of the hexamethylene diisocyanate manufacturer providing, i.e., supplying or manufacturing specific methanol also applies to the embodiments of methanol provision.

[0017] The production of methanol typically involves reacting carbon oxides with hydrogen (this mixture is also called synthesis gas). This process is exothermic and can be described by the following equation:

[0018]

number

[0019] Both reactions are linked by a similarly exothermic water-gas shift reaction, which can be described as follows:

[0020]

number

[0021] Traditionally, methanol synthesis has used synthesis gas, primarily composed of CO and H2, produced from natural gas (fossil methane) and steam in a reforming process (steam reforming). The composition of the synthesis gas significantly impacts its optimal utilization. The composition can be described by its stoichiometric number (SN).

[0022]

number

[0023] When SN=2, the reactants exist in stoichiometric ratios according to the reaction equation described above. However, in practice, slightly higher values ​​for SN (2.01-2.1) are used, which is achieved by a higher hydrogen content in the synthesis gas (Dittmeyer et al. "Chemical Technology", volume 4, 5th edition).

[0024] In the method according to the present invention, the carbon monoxide required for conversion to provide methanol is not provided by conventional steam reforming using a fossil carbon source (natural gas), but by partial reduction of carbon dioxide and / or partial oxidation (and gasification, if necessary) of the organic material to CO.

[0025] In the method according to the present invention, partial oxidation of an organic solid material (preferably an organic, polymer material) includes the conversion of the organic solid material into a CO-containing gas by partial oxidation, thereby providing CO from the organic solid material (preferably a spent polymer waste fraction) and an oxygen-containing gas (hereinafter also referred to as gasification).

[0026] The use of polymer-containing waste fractions (hereinafter referred to as polymer waste fractions), which may mainly consist of waste fractions containing, for example, PET, PE, PP, polyurethane, or polycarbonate, for the provision of CO means that these polymer-containing waste fractions are supplied for recycling and thus, with improved sustainability, produce hexamethylene diisocyanate, and also produce polyurethane from this hexamethylene diisocyanate.

[0027] A "polymer compound" is a molecule having a relative molecular weight (Mw) of at least 2000 g / mol, and its chemical structure contains many multiple repeating structural units derived from one or more different molecules with lower relative molecular weights. The average molar mass specified in the scope of this application for a polymer or polymer compound is always the weight-average molar mass Mw unless otherwise specified, which can, in principle, be determined by gel permeation chromatography using an RI detector, and it is convenient to perform the measurement against an external standard. A "polymer material" is a material containing at least one polymer compound.

[0028] Partial oxidation involves a partial oxidation reaction between an organic material (preferably an organic solid material, particularly preferably a polymeric organic material, and most particularly preferably a polymeric waste fraction) and oxygen, yielding a product gas mixture containing hydrogen and CO, and possibly by-products. The by-products are particularly hydrocarbons having 1 to 8 carbon atoms. CO2 and water vapor are also present in the product gas mixture.

[0029] Further by-products obtained in the gasification process are residual fractions that cannot be reacted further.

[0030] The temperature required for gasification is at least partially achieved by partial combustion (partial oxidation) of the organic solid material (preferably polymeric organic material, particularly preferably polymeric waste fraction) with an oxygen-containing gas. The partial oxidation of the introduced organic solid material is carried out in the reactor at a temperature of at least 400°C. Preferably, the partial oxidation of the material in the reactor is carried out at a temperature in the range of 600°C to 1500°C, particularly 850°C to 1400°C, more preferably 1100°C to 1300°C.

[0031] The carbon monoxide provided as a product of a partial oxidation method may be produced, for example, by a method for producing carbon monoxide for providing methanol, which includes at least the following steps:

[0032] 1) To provide an oxygen-containing gas stream containing at least 50% by weight of oxygen gas, 2) Partial oxidation of an organic material (preferably an organic material containing at least one polymeric organic compound), wherein the organic material is introduced into a reactor of the apparatus and treated therein by supplying at least the oxygen-containing gas stream and heat of at least 400°C to form a product gas, the resulting product gas is optionally discharged from the apparatus as a carbon monoxide-containing product gas stream together with particulate solids dispersed therein after at least one further partial oxidation step of the product gas; 3) Supply of carbon monoxide-containing product gas stream to the purification, and at least, 3-1) The carbon monoxide-containing product gas stream (i) Water is brought into contact with a carbon monoxide-containing product gas stream, and as a result, particulate solids dispersed in the carbon monoxide-containing product gas stream form slag, which is then removed and discharged. (ii) A stream of carbon monoxide-containing product gas, in which particulate solids have been purified, is discharged; It is supplied to the scrubbing process for solid separation, 3-2) The carbon monoxide-containing product gas stream, from which particulate solids have been purified by the scrubbing process, is supplied to at least one water separator in the drying process, water is separated, and the resulting carbon monoxide-containing product gas stream is discharged. 3-3) The carbon monoxide-containing product gas stream purified by the separation of water is fed into at least one carbon dioxide separator, carbon dioxide is separated, and the resulting carbon monoxide-containing product gas stream and carbon dioxide are discharged; 3-4) The carbon monoxide-containing product gas stream purified by the separation of carbon dioxide is supplied to at least one separation unit for the separation of carbon monoxide, the separation of carbon monoxide is performed, and the resulting residual gas containing carbon monoxide and hydrogen gas is discharged; 3-5) The hydrogen gas-containing residual gas separated using the separation unit may be supplied to a residual gas treatment facility, where hydrogen gas is separated and hydrogen gas and terminal gases are discharged.

[0033] A solid is known to be "particulate" when it is in the form of a granular mixture of numerous loose solid particles of the substance, which then includes what is known as grain. Granular is a term for the particulate component of powder (granular is loose solid particles), dust (granular is loose solid particles), granule (loose solid particles are aggregates of several granular particles), and other granular mixtures.

[0034] A "reactor" is the volume within which a chemical transformation, such as the partial oxidation of a polymeric organic compound, takes place. In the case of partial oxidation, this could be, for example, the volume of a heated container in which the material is contained.

[0035] The oxygen gas required for partial oxidation can be obtained, for example, from a water electrolysis or air separation plant. In a preferred embodiment of partial oxidation, the oxygen-containing gas stream is provided by performing electrolysis of water to obtain oxygen and hydrogen gases, and the oxygen gas from this electrolysis is used to provide the oxygen-containing gas stream.

[0036] Water electrolysis can be carried out in conventional plants. Industrial systems for alkaline water electrolysis and polymer electrolyte-based electrolysis, so-called PEM electrolysis, are known and commercially available. The principle of water electrolysis is described by example in Chapter 6.3.4 of Volkmar M. Schmidt's "Elektrochemische Verfahrenstechnik [Electrochemical process technology]" (2003 Wiley-VCH-Verlag; ISBN 3-527-29958-0).

[0037] According to the present invention, the organic solid material introduced into the reactor for partial oxidation preferably contains at least one polymeric organic compound. Partial oxidation should be carried out as uniformly and selectively as possible within the reactor. In preferred embodiments, these parameter increases can be achieved when, based on the time prior to introduction in each case, the weight ratio of oxygen gas present in the oxygen-containing gas stream to the polymeric organic compound is within the range of 0.4:1.0 to 1.2:1.0, preferably 0.6:1.0 to 0.9:1.0.

[0038] In a preferred embodiment, the partial oxidation of the introduced organic solid material is carried out at an absolute pressure greater than 1 bar, preferably in the range of 2 to 80 bar, and particularly preferably in the range of 2 to 50 bar.

[0039] Partial oxidation of organic solid materials can be carried out in at least one of the following three reactors: a reactor for jet gasification, a reactor for fluidized bed gasification, and a reactor for fixed bed gasification.

[0040] When used in reactors for jet gasification, organic solid materials have a median particle size of <0.1 mm X 50.3The material must be ground to a particle size (dust) having the following characteristics. The material is fed into the reactor either pneumatically or as a slurry. The greatest limitation of this type of partial oxidation for the chemical recycling of waste is the pulverizability and transportability of the heterogeneous waste-derived starting material. To produce "biotincture" with pulverizability similar to coal, heat treatment (roasting) of biomass at 200-300°C with the O2 removed is used. In another variation, upstream pyrolysis can be used to produce pumpable pyrolysis oil. The oil obtained by waste pyrolysis can be partially oxidized directly or in the form of a slurry mixed with solid pyrolysis residue (pyrolysis coke). This method configuration was developed by Noell (Noell-Konversionsverfahren zur Verwertung und Entsorgung von Abfallen [Noell conversion process for the recovery and disposal of waste], Jurgen Carl EF-Verl. fur Energie- und Umwelttechnik, 1994, ISBN:3924511829).

[0041] Another variation is the use of reactors for fluidized bed gasification. Gasification of organic solid materials, particularly waste, in fluidized bed reactors is well-known through the technologies of EBARA (Showa Denko, Japan) and ENERKEM (Enerkem, Edmonton, Canada), as well as the large-scale demonstration of high-temperature Winkler gas production (HTW) by Rheinbraun AG (now RWE) in Berlenrath, Germany from 1993 to 1997. Pretreatment for introducing organic materials or materials containing polymeric organic compounds into the reactor involves a median particle size of 30-80 mm X 50.3This requires grinding. Introduction into the reactor vessel is done via a screw conveyor, limiting the gasifier pressure to 10 bar or less. ENERKEM and EBARA technologies enable the gasification of high-calorie waste (plastic waste or plastic-rich alternative fuels). Fluidized bed gasifiers are operated at a gentle temperature of 700–950°C, well below the ash melting point of the feedstock, to avoid caking and coagulation within the reactor. A further advantage of this gentle reactor temperature is incomplete carbon turnover in the fluidized bed. Furthermore, the crude gas from the reactor for fluidized bed gasifiers typically contains a considerable amount of methane and other hydrocarbons. To compensate for this and ensure high synthesis gas yields of H2 and CO, the ENERKEM and EBARA processes utilize a second high-temperature stage for partial oxidation (approximately 1400°C) located just downstream of the fluidized bed to melt the fly ash and convert the hydrocarbons in the product gas from the first stage into a final carbon monoxide-containing product gas stream. ENERKEM calls this second stage the "thermal reforming unit," while EBARA calls it the "high-temperature gasification furnace." The high temperature in this second partial oxidation stage increases CO2 production.

[0042] The CO for methanol production may also preferably be a process product resulting from the conversion of methane from a biosource by partial oxidation in a classical reformer process. In the context of preferred embodiments of such production, the CO is a process product of the reaction of methane and steam from at least a biosource, supplying thermal energy at a temperature of at least 500°C (particularly preferably with the addition of CO2) to yield carbon monoxide. Further suitable sustainable reformer processes with the addition of CO2 are described in the PCT patent application no. PCT / EP2022 / 052267, the contents of which are fully and expressly incorporated herein by reference. This process comprises at least the following steps: The synthesis of carbon monoxide in a reforming apparatus process in which methane and steam from a biosource are reacted with at least CO2 addition and thermal energy supply at a temperature of at least 500°C to yield a carbon monoxide-containing product gas. Purification of the carbon monoxide-containing product gas obtained from the aforementioned synthesis by separation of at least CO2 and optionally at least one separation selected from the separation of water, hydrogen, or a combination thereof, in order to obtain carbon monoxide; The provision of CO2 for addition to the aforementioned reforming process, at least from the separation of CO2 in the aforementioned purification process. This relates to the production of carbon monoxide from bio-sources, including methane, water vapor, and CO2.

[0043] It is preferable that the thermal energy supplied to the reforming apparatus process for carbon monoxide synthesis is supplied by at least one method selected from (i) combustion of a hydrogen-containing fuel produced by renewable energy, (ii) combustion of a methane-containing fuel from a biosource, and (iii) conversion of electrical energy generated from renewable energy into heat.

[0044] "Bio-source methane" (also called "biomethane") is understood by those skilled in the art to mean methane industrially obtained from biomass through methane fermentation, in contrast to fossil methane. Methane fermentation is known to involve the anaerobic decomposition of organic matter by microorganisms. Bio-source methane is produced, for example, in biogas plants where both organic waste and renewable raw materials are appropriately fermented.

[0045] "Renewable energy" is understood by those skilled in the art to mean energy from inexhaustible energy sources, such as wind energy, hydroelectric energy, bioenergy (e.g., the conversion of biogas or biomass into electricity) or solar energy. Therefore, suitable renewable energy is most preferably wind, solar, hydroelectric, or a combination thereof.

[0046] According to the present invention, it is preferable that the methanol provided according to step a) i) of the method according to the present invention is a method product of the reaction of CO, where the CO used in the reaction is a method product of at least partial reduction of CO2 to CO, particularly selected from a reverse water-gas shift reaction using H2 produced by electrolysis (preferably by water electrolysis, i.e., by the electrolysis of water), from the electrochemical reduction of CO2 to CO, or a mixture thereof.

[0047] In a particularly preferred embodiment of the method according to the present invention, the methanol provided is provided as a method product of the conversion of CO, where the CO used in the conversion is CO with x=1 or 2 x The method product is produced by the production of at least a partial gas stream containing at least [a certain substance] and which may contain hydrogen gas.

[0048] In one embodiment of this method, it was further demonstrated that it is preferable that methanol is obtained by the conversion of CO2 with or without hydrogen and used for providing methanol. Then, it is particularly preferable that the reaction is an electrochemical reaction, a homogeneously catalyzed reaction or a heterogeneously catalyzed reaction. In further embodiments, the CO2 used therefor is derived from a further CO2 source, e.g., CO2 released in the provision of thermal energy, or from an external CO2 source, e.g., CO2 from industrial off-gas.

[0049] According to the present invention, the "electrochemical reaction" is carried out by applying an electric current to a reaction medium (for example, through at least one electrode immersed in the reaction medium) in the presence of at least one reactant (e.g., carbon dioxide).

[0050] A "catalyzed reaction" or "catalytic reaction" is defined as above (as shown above). According to the present invention, a "homogeneously catalyzed reaction" is carried out using a homogeneous catalyst, and a "heterogeneously catalyzed reaction" is carried out using a heterogeneous catalyst.

[0051] A preferred CO2 source is at least one "external CO2 source" that provides CO2 not released by the method according to the present invention. An external CO2 source is, for example, CO2 produced in cement production, in H2 production for ammonia synthesis, in fermentation, in off-gas from fuel combustion (e.g., waste incineration), or CO2 obtained from air.

[0052] In a particularly preferred embodiment of the method according to the present invention, carbon monoxide for methanol synthesis is produced from CO2 in a reverse water-gas shift (RWGS) reaction zone, through the reaction of at least hydrogen and CO2 to yield carbon monoxide. Such embodiments of carbon monoxide production are described, for example, in International Publication No. 2021 / 089737, the contents of which are fully and expressly incorporated herein by reference.

[0053] The "reaction zone" is a part of the reaction space within which a chemical reaction, such as a reverse water-gas shift reaction, takes place. The "reaction space" is the volume within which the co-reactants involved in the chemical reaction are brought together and the chemical reaction takes place. In the case of a chemical reaction, this could be the volume of the vessel within the reaction zone where the reactants, such as carbon dioxide in the case of the RWGS reaction, and its co-reactants, such as hydrogen in the case of the RWGS reaction, are present together and the reaction takes place. This volume could be, for example, that of a reactor.

[0054] The hydrogen gas used for the RWGS reaction is preferably provided by electrolysis, particularly by chlor-alkali electrolysis or water electrolysis, and most preferably by water electrolysis. This then preferably uses electrical energy generated from renewable energy sources (particularly from hydropower, solar energy or wind power) in each case.

[0055] In a particularly preferred method, the carbon monoxide provided for the provision of methanol is obtained by at least the following steps: Provision of CO2 gas flow, Purification of CO2 gas streams from by-components, particularly nitrogen oxides, sulfur compounds, dust, water, oxygen, and HCl, by optional adsorption, gas scrubbing, or catalytic treatment, in order to obtain purified carbon dioxide. The introduction of hydrogen gas, provided along with a stream of purified CO2 gas, into the RWGS reaction zone, and the reaction of the reactants according to the principle of the RWGS reaction to give a product gas mixture consisting of water vapor, CO, and optionally by-products, particularly lower hydrocarbons, especially methane. In particular, separation of unreacted carbon dioxide from the gas mixture of the RWGS reaction obtained by amine scrubbing, and recycling of the unreacted carbon dioxide into the RWGS reaction. In particular, the use of a cold box, separation of unconverted hydrogen from the gas mixture of carbon monoxide and hydrogen obtained after separation in the RWGS reaction, and optionally recycling of hydrogen during the RWGS reaction. Emission of residual carbon monoxide from separation It is a product of a method that includes

[0056] The CO2 source for providing the CO2 gas stream is, for example, CO2 released during the provision of thermal energy for the method according to the present invention (e.g., for the RWGS reaction), CO2 obtained from air separation, or CO2 from a further external CO2 source.

[0057] An external CO2 source provides CO2 that is not emitted by the method according to the invention or by embodiments thereof. The external CO2 source is, for example, CO2 formed in off-gases during cement production or during the combustion of fuels (e.g., waste incineration), or CO2 obtained from air. This CO2 from the external CO2 source is, in a preferred embodiment of the method according to the invention, (i) from process gases or off-gases selected from at least one process selected from cement production, H2 production, incineration, and / or (ii) achieved by absorption of the CO2 fraction from air by introduction into an alkali metal hydroxide solution, such as a potassium hydroxide solution. This results in the formation of potassium bicarbonate, which can then be thermally decomposed back to CO2 and potassium hydroxide. The released CO2 is then fed to the method according to the invention for the synthesis of carbon monoxide.

[0058] The RWGS reaction is preferably carried out in the reaction zone at a temperature of 650 °C or higher, particularly preferably 700 °C or higher, and extremely particularly preferably 750 °C or higher.

[0059] The RWGS reaction is preferably carried out in the presence of at least one catalyst. The latter is more preferably selected from at least one compound from the following group.

[0060] (I) Formula A (1-w-x) A’ w A” x B (1-y-z) B’ y B” z O 3-デルタ mixed metal oxides where A, A’ and A” are independently selected from the group of Mg, Ca, Sr, Ba, Li, Na, K, Rb, Cs, Sn, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Tl, Lu, Ni, Co, Pb, Bi and / or Cd; B, B', and B'' are independently selected from the group consisting of Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn, Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb, Hf, Zr, Tb, W, Gd, Yb, Mg, Li, Na, K, Ce, and / or Zn; 0≦w≦0.5;0≦x<0.5;0≦y≦0.5;0≦z≦0.5 and -1≦delta≦I;

[0061] (II) Equation A (1-w-x) A' w A” x B (1-y-z) B' y B” z O 3-デルタ A mixed metal oxide, in the formula, A, A', and A'' are independently selected from the group Mg, Ca, Sr, Ba, Li, Na, K, Rb, Cs, Sn, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Tl, Lu, Ni, Co, Pb, and / or Cd; B is selected from the group consisting of Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn, Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb, Hf, Zr, Tb, W, Gd, Yb, Mg, Cd, Zn, Re, Ru, Rh, Pd, Os, Ir and / or Pt; B' is selected from the group Re, Ru, Rh, Pd, Os, Ir and / or Pt; B'' is selected from the group Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn, Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb, Hf, Zr, Tb, W, Gd, Yb, Mg, Cd and / or Zn; 0≦w≦0.5;0≦x≦0.5;0≦y≦0.5;0≦z≦0.5 and -I≦delta≦1;

[0062] (III) A mixture of at least two different metals M1 and M2 on a support containing an Al, Ce and / or Zr oxide doped with metal M3; In the formula, M1 and M2 are independently selected from the group Re, Ru, Rh, Ir, Os, Pd, and / or Pt; M3 is selected from the group Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and / or Lu;

[0063] (IV) Form LO x (M (y / z) Al (2-y / z) O3) z Mixed metal oxides of; in the formula, L is selected from the group of Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Sc, Y, Sn, Pb, Pd, Mn, In, Tl, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and / or Lu; M is selected from the group Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Zn, Cu, Ag and / or Au; 1 <x≦2;0<y≦12;および4≦z≦9;

[0064] (V) Formula LO(Al2O3) z Mixed metal oxides of; in the formula, L is selected from the group of Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Sc, Y, Sn, Pb, Mn, In, Tl, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and / or Lu; 4≦z≦9;

[0065] (VI) Oxidation catalysts containing Ni and Ru;

[0066] (VII) Metal M1 and / or at least two different metals M1 and M2 on and / or within the support, the support is Carbides, oxycarbides, carbonitrides, nitrides, borides, silicides, germanides, and / or selenides of metal A and / or B; M1 and M2 are independently selected from the group consisting of Cr, Mn, Fe, Co, Ni, Re, Ru, Rh, Ir, Os, Pd, Pt, Zn, Cu, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and / or Lu; A and B are independently selected from the group Be, Mg, Ca, Sc, Ii, V, Cr, Mn, Fe, Co, Ni, Y, Zr, Nb, Mo, Hf, Ta, W, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and / or Lu; and / or Reaction products of (I), (II), (III), (IV), (V), (VI), and / or (VII) at a temperature of 700°C or higher in the presence of carbon dioxide, hydrogen, carbon monoxide, and / or water.

[0067] In equally preferred embodiments of the above method, the methanol provided for the provision of hexamethylenediamine in the method according to the present invention is provided from carbon monoxide, where carbon monoxide is the product of the electrochemical partial reduction of carbon dioxide to yield carbon monoxide. In this embodiment, CO provision is carried out by introducing a CO2 gas stream into an electrolytic device and reducing the stream to carbon monoxide at an electrode, preferably a gas diffusion electrode (particularly preferably using electrical energy generated from renewable energy). This electrochemical partial reduction is hereafter also referred to as CO2 electrolysis.

[0068] CO2 electrolysis can be a high-temperature electrolysis, for example, operated at temperatures exceeding 600°C, sometimes with the addition of water for synthesis gas production. High-temperature electrolysis is known in principle and is commercially available, for example, from Haldor Topsoe, eCOs®. High-temperature electrolysis forms oxygen at the anode.

[0069] When CO2 electrolysis is performed as low-temperature electrolysis, the electrolysis is carried out at a temperature below 150°C.

[0070] In all CO2 electrolysis processes, CO2 gas is supplied to the cathode space.

[0071] In low-temperature electrolysis, CO2 is converted to carbon monoxide and optionally hydrogen, particularly at a gas diffusion electrode. Those skilled in the art know, for example, electrodes and methods for the electrochemical reduction of CO2 from International Publication No. 2021 / 069470. The electrochemical reduction of CO2 is preferably carried out by the method of International Publication No. 2021 / 069470, which is fully and expressly incorporated herein by reference. In this preferred electrolytic method for the production of carbon monoxide, carbon monoxide is obtained by the electrochemical conversion of a carbon dioxide and alkali metal chloride solution, and hydrogen and chlorine may also be obtained. This preferred electrolysis method is characterized in that carbon dioxide is electrochemically reduced in an aqueous alkali metal chloride-containing solution as the cathode at a gas diffusion electrode as the cathode, while chlorine is simultaneously anodeally produced from the aqueous alkali metal chloride-containing solution as the anode, and then the alkali metal salt of the carbon dioxide formed in the cathode, selected from alkali metal carbonates, alkali metal bicarbonates, or mixtures thereof, reacts with hydrogen chloride to yield carbon dioxide and alkali metal chlorides, the released carbon dioxide is returned to the cathode space for the gas diffusion electrode, and the generated alkali metal chlorides are returned to either the anode space and / or the cathode space.

[0072] According to known principles, the MEA (membrane-electrode junction) concept can also be used in low-temperature electrolysis. In this case, the catalyst is applied to the membrane. An upstream gas diffusion layer controls the transport of gases and liquids. This can be done on both the anode and cathode sides. It is also possible to have the gas diffusion electrode in direct contact with the membrane.

[0073] The gas diffusion electrode used may be installed in the electrolytic cell in a zero-gap or finite-gap configuration. A preferred configuration for low-temperature electrolysis of CO2 is described in International Publication No. 2020 / 057998, which is fully and explicitly incorporated by reference.

[0074] The cathode space, or a gas diffusion electrode placed within it, may be supplied with excess CO2. "Excess" means introducing more CO2 than is necessary for the stoichiometric conversion based on the current flowing. Consequently, a gas mixture consisting of unreacted CO2, CO, and H2 leaves the cathode space.

[0075] In a further embodiment of CO2 electrolysis, it is preferable that the electrical energy used for CO2 electrolysis is generated from renewable energy sources, particularly wind, solar, or hydroelectric power.

[0076] If the carbon monoxide used to provide methanol is a method product of at least one of the aforementioned methods, the reaction of CO to give methanol may use at least one of the methods known to those skilled in the art, which proceed from CO-containing synthesis gas.

[0077] If step ii-1) does not directly provide CO mixed with sufficient hydrogen as synthesis gas, then, in case of a lack of sufficient hydrogen gas, the CO is mixed with hydrogen gas to provide synthesis gas before conversion to methanol. This hydrogen gas, which is added to CO in the context of providing methanol, is preferably provided by electrolysis, particularly by chlor-alkali electrolysis or water electrolysis. Water electrolysis can be carried out in conventional plants. Industrial systems for alkaline water electrolysis and polymer electrolyte-based electrolysis, so-called PEM electrolysis, are known and commercially available. The principle of water electrolysis is described as an example in Chapter 6.3.4 of Volkmar M. Schmidt's "Elektrochemische Verfahrenstechnik [Electrochemical process technology]" (2003 Wiley-VCH-Verlag; ISBN 3-527-29958-0). In further embodiments, it is preferable that the electrical energy used for electrolysis for hydrogen production is generated from renewable energy sources, particularly wind, solar, or hydroelectric energy.

[0078] Embodiments are particularly preferred in which the methanol provided for the method according to the present invention is produced in proportion to the method product using renewable energy, preferably in a geographical location with good availability of renewable energy, for the purpose of subsequently providing the methanol for the method of the present invention by either delivery by transport in a container or delivery by methanol flow in a continuous process. For provision in the context of a continuous process, the methanol production is preferably fluidly connected to the production of hexamethylenediamine, for example, via a pipe conduit.

[0079] Methanol production equipment is licensed on the market from companies such as Air Liquide and Johnson Matthey. An overview of the classic production of methanol from synthesis gas is published, for example, in Ott et al., Methanol in: Ullmann's Encyclopedia of Industrial Chemistry, 2012, Wiley-VCH Verlag, Weinheim (doi 10.1002 / 14356007.a16_465.pub3), which is fully and explicitly incorporated by reference.

[0080] The methanol provided as described above in step a)i) is used in step a)ii) of the method according to the present invention for providing hexamethylenediamine, in at least the following steps: Providing propene as a product of a method comprising at least the following steps: ii-1) Conversion of methanol provided earlier to give a product mixture containing dimethyl ether, water, and methanol; ii-2) Conversion of the aforementioned product mixture to propene from a starting material containing dimethyl ether, water, and methanol in each case, by contact with a catalyst, preferably with at least one zeolite compound, at a temperature above 200°C. It is converted to propene by a process that includes it.

[0081] Steps ii-1) and ii-2) are part of the methanol to propylene process (also known as the MTP process). The MTP process was first developed by Lurgi.

[0082] In the MTP process, for example, gaseous methanol is reacted in a reactor on a catalyst to give a product mixture containing dimethyl ether, water, and methanol in the sense of step ii-1) of the method according to the present invention. Suitable reactors include, for example, fixed-bed reactors or fluidized-bed reactors.

[0083] In a preferred embodiment of the method according to the present invention, the reaction of the provided methanol according to step a)ii-1) is carried out by contacting methanol, preferably methanol in the gas phase, with a catalyst.

[0084] A suitable and particularly preferred catalyst for converting methanol in step ii-1) is an Al2O3 pellet, as described in European Patent No. 0448000 or German Patent Application Publication No. 19723363.

[0085] Prior to the conversion of methanol in step a)ii-1), the provided methanol is preferably heated to a temperature in the range of 200°C to 350°C, and the conversion is carried out using this appropriately temperature-controlled methanol. After the conversion, the product mixture containing dimethyl ether, methanol, and water then preferably has a temperature of 350°C to 450°C.

[0086] In particular, the product mixture from step ii-1) in the form of a gaseous flow is introduced into a further reactor as a starting material for step ii-2), after optionally performing an optional purification step, where it is converted to propene on a catalyst. Examples of suitable catalysts are catalysts or zeolite compound catalysts sold by Clariant under the trade name MTPROP®, as described, for example, in column 1, lines 43-52 of U.S. Patent No. 7,015,369, and in Examples 1 and 2. In further embodiments of the method according to the present invention, the starting material is preferably converted to propene by contact with a zeolite compound as a catalyst.

[0087] In step ii-2), it is preferable to react the starting materials at a temperature of 350°C to 600°C, particularly 380°C to 550°C.

[0088] Optionally, after separation of by-components, the propene provided by step ii-2) of the method according to the present invention is reacted with ammonia to give acrylonitrile according to step iii). For the provision of hexamethylenediamine, according to the present invention, it is sufficient that the acrylonitrile used therefor is an actual method product of at least steps i), ii), and iii) described in a). This means that in order to carry out the step of providing hexamethylenediamine, it is sufficient to simply take the acrylonitrile produced in the manner described, in the context of delivery as a raw material, from a storage container or supply conduit to supply the acrylonitrile to at least step a)iv) of the method according to the present invention. In this case, the hexamethylenediisocyanate producer, as an implementer of the method according to the present invention, does not carry out steps i), ii), and iii) for producing acrylonitrile as described in a) of the method according to the present invention, but rather merely ensures that the provided hexamethylenediamine is produced from acrylonitrile synthesized by the application of at least steps i), ii), and iii) described in a), and therefore is an actual method product.

[0089] For the synthesis of acrylonitrile from propene, at least the following steps are required: iii-1-1) Provision of hydrogen gas by electrolysis of water, preferably using electrical energy generated from renewable energy sources; iii-1-2) Reaction of provided hydrogen gas with gaseous nitrogen to yield ammonia As an actual method product of the method, ammonia is first provided.

[0090] The electrolysis of water to be carried out in step iii-1-1) for the synthesis of the hydrogen gas to be supplied can be carried out in a plant according to the prior art. Industrial systems for alkaline water electrolysis and polymer electrolyte-based electrolysis, so-called PEM electrolysis, are known and commercially available. The principle of water electrolysis is described by example in Chapter 6.3.4 of Volkmar M. Schmidt's "Elektrochemische Verfahrenstechnik [Electrochemical process technology]" (2003 Wiley-VCH-Verlag; ISBN 3-527-29958-0).

[0091] The production of ammonia is carried out in accordance with step a)iii-1-2), starting from nitrogen and hydrogen provided in the preceding step a)iii-1-1), as described by the Haber-Bosch process, using known reactor techniques and designs for this method, for example, which are fully and expressly incorporated herein by reference.

[0092] For the supply / production of ammonia, it has been found to be advantageous when the nitrogen used therefor is supplied by air separation. Methods for air fractionation and appropriately suitable plants for ammonia production are part of the prior art and are available on the market.

[0093] Next, preferably according to the so-called SOHIO method (e.g., U.S. Patent No. 2904580), the propene provided by at least the aforementioned method steps is reacted oxidatively with the provided ammonia to give acrylonitrile. According to the present invention, it is preferable that the reaction of the provided ammonia with propene according to step a)iii-2) is carried out using oxygen from air at a temperature of 350°C to 550°C.

[0094] In a further embodiment of the method for producing acrylonitrile provided, the reaction is carried out at a relative pressure of 40 to 220 kPa, which is particularly preferred.

[0095] It has been found to be advantageous to carry out the reaction of the provided ammonia with propene according to step a)iii-2) on a molybdate and / or antimonate catalyst. In this embodiment, it is then preferable that the aforementioned temperature is established and the reaction is carried out using oxygen, preferably oxygen from air.

[0096] Acrylonitrile produced according to step iii-2) of the method according to the present invention is electrochemically converted to adiponitrile (CAS number 111-69-3, also known as adipic acid dinitrile) according to step iv). For the provision of hexamethylenediamine, according to the present invention, it is sufficient that the adiponitrile used therefor is the actual method product of at least steps i), ii), iii), and iv) described in a). This means that in order to carry out the step of providing hexamethylenediamine, it is sufficient to simply take the adiponitrile produced in the manner described outward from a storage container or from a supply conduit in the context of delivery as a raw material to supply the adiponitrile to at least step a)v) of the method according to the present invention. In this case, the hexamethylene diisocyanate producer, as an implementer of the method according to the present invention, does not carry out steps i), ii), iii), and iv) for producing adiponitrile as described in a) of the method according to the present invention, but rather merely assures that the provided hexamethylenediamine was produced from adiponitrile synthesized by applying at least steps i), ii), iii), and iv) as described in a), and is therefore the actual method product.

[0097] The adiponitrile is produced by at least the following steps Introducing water, a mixture containing the acrylonitrile and at least one electrolyte salt from step a)iii-2) into the cathode space of the electrolytic cell, and bringing the mixture into contact with the cathode to which an electric current is applied; Cathodic hydrogenation dimerization of acrylonitrile to form an adiponitrile-containing product mixture; Discharge of adiponitrile-containing product mixture from the cathode space of the electrolytic cell and optional purification of adiponitrile. The actual method product must be the product.

[0098] These steps are carried out, for example, as described in U.S. Patent No. 3,193,480, which is incorporated fully and expressly herein by reference.

[0099] To provide the mixture, at least water, the acrylonitrile, and at least one electrolyte salt are mixed. Preferably, this forms an emulsion of acrylonitrile-containing droplets in water.

[0100] In preferred embodiments, a suitable electrolyte salt in the cathode space of the electrolytic cell is at least one quaternary ammonium salt, particularly at least one quaternary ammonium sulfonate. Particularly preferred electrolyte salts are selected from at least one electrolyte salt from the group formed by tetraalkylammonium salts, tetraalkanolammonium salts, dialkyldialkanolammonium salts, alkyltrialkanolammonium salts, trialkylalkanolammonium salts, trialkylbenzylammonium salts, and quaternary N-heterocyclo-N-alkylammonium salts, and then, more preferably, these sulfonates are suitable. Particularly preferred alkyl groups of the ammonium cation of the aforementioned salts include (C1-C6) alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, and tert-butyl. Particularly preferred alkanol groups include (C1-C6) hydroxyalkyl groups such as 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, and 4-hydroxypropyl. Particularly preferred suitable N-heterocyclo groups include, for example, piperidinium, morpholinium, and pyrrolidinium.

[0101] Preferably, suitable anions for quaternary ammonium salts include chlorides, fluorides, sulfates, phosphates, and sulfonates.

[0102] Tetraalkylammonium salts of aryl- or alkylarylsulfonic acids particularly preferably include electrolyte salts. Particularly preferred sulfonate anions of quaternary ammonium salts that can be preferably used as electrolyte salts include benzenesulfonate, o-tolylsulfonate, m-tolylsulfonate, o-tolylsulfonate, m-tolylsulfonate, p-tolylsulfonate, o-cumylsulfonate, m-cumylsulfonate, p-cumylsulfonate, α-naphthylsulfonate, β-naphthylsulfonate, p-xylylsulfonate, or mixtures thereof. Particularly preferred sulfate anions are selected from at least one anion having an organic group similar to the organic group of the sulfonate anion described above.

[0103] In the most preferred embodiment, at least one electrolyte salt is tetramethylammonium chloride, tetraethylammonium chloride, tetra(n-butyl)ammonium chloride, tetraethylammonium p-tolylsulfonate, tetraethylammonium o-tolylsulfonate, tetraethylammonium m-tolylsulfonate, tetraethylammonium benzenesulfonate; tetraethylammonium o-, m- or p-cumylsulfonate or o-, m- or p-ethylbenzenesulfonate; N,N-dimethylpiperidinium o-, m- or p-tolylsulfonate or o-, m- or p-biphenylsulfonate; tetrabutylammonium α- or β-naphthylsulfonate or o-, m- or p-tolylsulfonate; tetrapropylammonium o-, m- or p-amylbenzenesulfonate or α-ethyl-β-naphthylsulfonate; tetra(2-hydroxyethyl Ammonium o-, m-, or p-cumylsulfonate or o-, m-, or p-tolylsulfonate; tetra(4-hydroxybutyl)ammonium benzenesulfonate or p-xylyl-3-sulfonate; tetrapentylammonium o-, m-, or p-tolylsulfonate or o-, m-, or p-hexylbenzenesulfonate, tetrapentanolammonium p-cumyl-3-sulfonate or benzenesulfonate; methyltriethylammonium o-, m-, or p-tolylsulfonate or mesityl-2-sulfonate; trimethylethylammonium o-xylyl-4-sulfonate or o-, m-, or p-tolylsulfonate; triethylpentylammonium α- or β-naphthylsulfonate or o-, m-, or p-butylbenzenesulfonate, trimethylhydroxyethylammonium benzenesulfonate or o-, m-, or p-tolylsulfonate;Selected from N,N-diethylpiperidinium or N-methylpyrrolidinium o-, m- or p-hexylbenzene sulfonate or o-, m- or p-tolylsulfonate, N,N-diisopropyl or N,N-dibutylmorpholinium o-, m- or p-tolylsulfonate or o-, m- or p-biphenyl sulfonate or a mixture of the aforementioned salts.

[0104] In a further preferred embodiment, it is advantageous that the mixture introduced in steps a) and iv) has a pH in the range of pH 7 to pH 10, particularly pH 7 to pH 9.5. The pH of the mixture in the cathode space is important for the normality of the anode liquid in the anode space of the electrolytic cell and for the H2 from the anode space to the cathode space. + It is even more preferable that the movement is controlled by the formal movement of ions. For this purpose, the anodic acid in the anode chamber of the electrolytic cell preferably has a normality in the range of 0.4 to 1.2.

[0105] In a preferred embodiment, the electrolytic cell in which electrochemical hydrogenation dimerization is carried out comprises a cathode space and an anode space separated from each other by a membrane. Suitable membranes include, for example, the membrane referred to in U.S. Patent No. 3,193,480, or are commercially available under trade names such as Nafion® 115.

[0106] In a further embodiment of this method, the electrolytic cell is preferably 5 to 20 volts and 15 to 40 A / dm 2 It is preferable that a current having the specified current density is applied.

[0107] According to the present invention, it is even more preferable that the cathodic hydrogenation dimerization of acrylonitrile to adiponitrile is carried out via an applied electric current actually generated using renewable energy selected from wind, hydro, solar energy or a mixture thereof.

[0108] The adiponitrile provided in steps a)iv) is converted to hexamethylenediamine via catalytic hydrogenation with hydrogen by a method known to those skilled in the art (preferably at a temperature in the range of 100°C to 200°C and an operating pressure in the range of 28 to 41 MPa). Hydrogenation is more preferably carried out in the liquid phase, and ammonia may be added as a medium for heat transfer. Suitable catalysts for catalytic hydrogenation of adiponitrile include, in particular, cobalt-containing catalysts such as those described in U.S. Patent Nos. 3,232,888, 3,821,305, 3,773,832 or 4,598,058. Equally usable are iron-containing catalysts such as those described in U.S. Patent Nos. 3,696,153 or 4,587,228.

[0109] Step b) of the method according to the present invention includes producing phosgene. This includes first providing carbon monoxide, which is at least the actual method product of the method described in step b)i) of the method according to the present invention.

[0110] For the provision of carbon monoxide in the context of the present invention, it is sufficient that the carbon monoxide is a method product of at least the method described in step b)i). This means that, when carrying out the method according to the present invention, for the performance of the step of providing carbon monoxide, it is sufficient to simply take the carbon monoxide from a storage container or a supply conduit as the actual method product of the said step in the context of delivery as a raw material. In this case, the hexamethylene diisocyanate producer, as an implementer of the method according to the present invention, does not produce the carbon monoxide himself, but rather merely ensures that the provided carbon monoxide was produced in proportion by the supplier and is the actual method product of at least the method described in step b)i).

[0111] In one embodiment, according to the present invention, in order to provide carbon monoxide, the aforementioned steps for carbon monoxide production are carried out by the hexamethylene diisocyanate producer itself in step b)i) as an essential step of the method according to the present invention, and the resulting carbon monoxide is similarly sent to the production of phosgene in step b)ii).

[0112] Embodiments of the partial reduction of CO2 to CO and the partial oxidation of an organic material to CO, as described in step b)i), in which at least one organic material is selected from at least one organic solid compound, methane from a biosource, or a mixture thereof, have already been described in step a)i-1) (see above). These also apply accordingly to step b)i).

[0113] In step b)i), carbon monoxide may also be derived from the partial oxidation of at least one monohydroxyalkyl compound, particularly methanol. This step is hereafter referred to as catalytic cracking. Preferably, the monohydroxyalkyl compound is methanol, and methanol is a method product of at least the step described in a)i). The embodiments described in step a)i) should be considered again (see above).

[0114] In the catalytic cracking step of methanol, the provided methanol is catalytically cracked by contacting gaseous methanol with a catalyst, in a preferred embodiment, to also form carbon monoxide and optionally hydrogen gas. If methanol is not in gaseous form for this purpose (e.g., when taken from a storage container), methanol is subjected to evaporation beforehand. The energy input required for evaporation can be generated by utilizing fossil fuels, such as natural gas, as an energy source. To establish the temperature required for evaporation, the method according to the present invention is supplied with thermal energy provided by at least one method selected from (i) combustion of a fuel containing hydrogen (gaseous H2) produced using renewable energy, (ii) combustion of a fuel containing methane from a biosource, or (iii) conversion of electrical energy generated from renewable energy into heat. Herein, it is particularly preferred that the renewable energy used is wind, solar, hydro, or a mixture thereof.

[0115] Gaseous methanol is preferably passed over a catalyst containing at least one transition metal species for catalytic cracking of the active component. Transition metal species are understood by those skilled in the art to mean all d-block elements and their chemical compounds. The catalyst is particularly preferably a transition metal species applied to a support. At least one transition metal species selected from Group VII, Group VIII, or Group XI of the periodic table is very particularly preferred, and preferably, then applied to the support.

[0116] Catalytic cracking of methanol is preferably carried out at a temperature below 500°C, more preferably below 400°C. If energy input is required for the catalytic cracking of methanol, this can be provided by utilizing fossil fuels, such as natural gas, as the energy source. To establish the temperature required for the catalytic cracking of methanol, the method according to the present invention is particularly preferably supplied with thermal energy provided by at least one method selected from (i) combustion of a fuel containing hydrogen (gaseous H2) produced using renewable energy, (ii) combustion of a fuel containing methane from a biosource, or (iii) conversion of electrical energy generated from renewable energy into heat. Herein, it is particularly preferable that the renewable energy used is wind, solar, hydro, or a mixture thereof.

[0117] The catalytic decomposition of methanol is preferably carried out at a temperature of at least 200°C. Subsequently, the catalytic decomposition of methanol is preferably carried out at a temperature of 200°C to less than 500°C, and particularly preferably 200°C to less than 400°C.

[0118] The catalytic cracking of methanol is preferably carried out at an absolute pressure of less than 50 bar, more preferably less than 40 bar.

[0119] The product gas obtained from catalytic cracking contains not only carbon monoxide but often methanol, carbon dioxide, hydrogen, and water, and may also contain by-products that may originate from the group of ethers (dimethyl ether), alcohols (ethanol), aldehydes, or esters. Prior to the reaction with chlorine to give phosgene, the product gas obtained from catalytic cracking is preferably subjected to a purification step in which methanol, carbon dioxide, hydrogen, and water are separated and carbon monoxide by-products are separated in a preferred additional method step.

[0120] The carbon monoxide provided for step b)ii) is preferably purified and detrimental before phosgene production. For this purpose, the carbon monoxide is preferably sent for carbon dioxide separation in a CO2 separation unit in which CO2 is separated.

[0121] CO2 separation units, and therefore CO2 separation, can take the form of "amine scrubbing," in which the carbon monoxide-containing product gas from the reforming unit process is subjected to scrubbing of a gas mixture by the principle of chemiadsorption with amines such as monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA), or diglycolamine (DGA), as is generally known, to achieve a highly purified gas mixture in an absorption column.

[0122] In one more preferred embodiment of the method according to the present invention, the separation of water from the provided carbon monoxide is performed.

[0123] In a further preferred embodiment of the above method, the separation of carbon dioxide is performed after water has been previously separated from the supplied carbon monoxide. For this purpose, the supplied carbon monoxide is first sent to a water separation unit, in which water is separated, and the carbon monoxide-containing dry product gas obtained after the separation of water is sent to a CO2 separation unit, in which CO2 is separated. In the water separation unit, the separation of water is performed, for example, by cooling the supplied carbon monoxide and separating the water as a condensate.

[0124] A preferred variation of the method according to the present invention is a method in which provided carbon monoxide (preferably from which water and CO2 have been pre-removed) is introduced into an H2-CO separation unit in which hydrogen is separated. This forms at least one gas stream in which the gas at 25°C and 10¹³ mbar contains at least 95 vol% carbon monoxide, more preferably at least 99 vol% carbon monoxide. The introduced carbon monoxide is preferably first separated into two gas streams within the H2-CO separation unit. This forms a further gas in the form of a gas stream containing at least 95 vol% (preferably at least 99 wt%) carbon monoxide, the largest component of which is hydrogen, and in particular carbon monoxide. This further gas is also called the tail gas from the H2-CO separation, or the terminal gas if no tail gas treatment is performed. The H2-CO separation unit operating by this separation principle is a so-called cold box. The hydrogen-containing residual gas from the H2-CO separation can be reintroduced into methanol production.

[0125] In the following steps b) and ii), the carbon monoxide obtained (optionally after purification) is reacted with chlorine on a catalyst to yield phosgene. More preferably, the catalyst is activated carbon.

[0126] For providing chlorine effective for phosgene synthesis in this embodiment, the production of chlorine gas from electrochemical oxidation by electrolysis of hydrochloric acid using a gas diffusion electrode (also known as HCl ODC electrolysis (ODC = oxygen-depleting electrode)); see U.S. Patent No. 6022,634 and International Publication No. 03 / 31690 for suitable electrolytic cells), production of chlorine gas from hydrochloric acid diaphragm electrolysis (see European Patent Application Publication No. 1103636), production of chlorine gas from thermal catalytic gas-phase oxidation (see International Publication No. 2012 / 025483), and production of chlorine from chlor-alkali electrolysis (see International Publication No. 2009 / 007366) are well known to those skilled in the art. The contents of the above-mentioned references in relation to the production of chlorine gas are explicitly and fully referenced. A preferred variation of this embodiment is a method by which the chlorine required for the synthesis of phosgene is produced electrochemically, particularly by electrochemical oxidation by hydrochloric acid electrolysis using a gas diffusion electrode, by electrochemical oxidation by hydrochloric acid diaphragm electrolysis, or by electrochemical oxidation by chlor-alkali electrolysis. In this case, it is then particularly preferred that the electrochemical oxidation be carried out using electricity generated from renewable energy, particularly in the form of wind, solar, or hydroelectric energy, in each case.

[0127] In step c) of the method according to the present invention, phosgene is reacted with hexamethylenediamine provided according to step a) to produce hexamethylene diisocyanate. Corresponding methods and apparatus for the reaction of phosgene with organic amine compounds are known to those skilled in the art, for example, from International Publication No. 2017 / 093215, which is fully and expressly incorporated herein by reference. In preferred embodiments, it has been found advantageous in the context of this method to react phosgene and hexamethylenediamine in the gas phase to obtain hexamethylene diisocyanate. The phosgenation of amines in the gas phase is known in itself and can be carried out as described, for example, in European Patent Publication No. 0289840, European Patent Publication No. 1319655, European Patent Publication No. 1555258, European Patent Publication No. 1275639, European Patent Publication No. 1275640, European Patent Publication No. 1449826, European Patent Publication No. 1754698, German Patent Publication No. 10359627, German Patent Publication No. 102005042392 or International Publication No. 2017 / 093215.

[0128] The second subject of the present invention is at least the following steps: Providing hexamethylene diisocyanate, a method product of the first subject matter of the present invention; Providing at least one type of organic polyol; Reaction of the hexamethylene diisocyanate with the organic polyol to yield polyurethane. This is a method for producing polyurethane, including [a specific component].

[0129] Organic polyols should be understood to mean organic compounds having at least two hydroxyl groups. These are preferably selected from polyester polyols, polyether polyols, polycarbonate polyols, polyether ester polyols, polyacrylate polyols, polyester polyacrylate polyols, or mixtures thereof, and are particularly preferably selected from the group of polyether polyols and / or polyester polyols.

[0130] In a preferred embodiment, a method for producing polyurethane is characterized in that the provision of hexamethylene diisocyanate is carried out using a multi-component system according to a third subject of the present invention (see below).

[0131] The third subject of the present invention is a multiple component system for producing hexamethylene diisocyanate by the manufacturing method of the first subject of the present invention, i) A volume filled with hexamethylenediamine, which is the method product of step a) of the method according to the first subject of the present invention; ii) A volume filled with carbon monoxide, which is the method product of step b)i-1) of the method according to the first subject of the present invention; iii) At least one electrolytic apparatus for the production of chlorine; iv) at least one reactor for the production of phosgene, the reactor having at least one inlet for chlorine which is fluid-connected to the electrolytic apparatus for the production of chlorine, and at least one inlet for carbon monoxide which is fluid-connected to the volume filled with carbon monoxide; v) At least one reactor for the production of hexamethylene diisocyanate, comprising at least one inlet for phosgene and at least one inlet for hexamethylenediamine, wherein the inlet for phosgene is fluid-connected to the reactor for the production of phosgene, and the inlet for hexamethylenediamine is fluid-connected to the volume of hexamethylenediamine, and It is a multi-component system that includes [the specified feature].

[0132] All embodiments of step a) of the method according to the present invention for producing hexamethylene diisocyanate are also applicable to multiple component systems.

[0133] All embodiments of step b) of the method according to the present invention for producing hexamethylene diisocyanate are also applicable to multiple component systems.

[0134] Therefore, a fourth subject of the present invention is the use of methanol as a raw material for producing the hexamethylenedi group of hexamethylenediisocyanate. The corresponding use carried out by the method according to the first subject of the present invention is preferred.

Claims

1. A method for producing hexamethylene diisocyanate for the manufacture of polyurethane, comprising at least the following steps: a) Providing a hexamethylenediamine method product of a method comprising at least the following steps: i) Providing methanol as a method product of a method comprising at least the following steps: i-1) CO ２ A method for at least partial reduction of carbon monoxide to CO as a product and / or a method for at least partial oxidation of an organic material to CO as a product, wherein at least one organic material is selected from at least one organic, solid compound, methane from a biosource or a mixture thereof; i-2) Conversion of the provided carbon monoxide to methanol; ii) Synthesis of propene from methanol provided earlier by at least the following steps: ii-1) Conversion of methanol as previously provided to give a product mixture containing dimethyl ether, water, and methanol; ii-2) Conversion of the product mixture to propene in each case from a starting material containing dimethyl ether, water, and methanol by contact with a catalyst, preferably with at least one zeolite compound as a catalyst, at a temperature above 200°C; (iii) Synthesis of acrylonitrile from propene by at least the following steps: iii-1) Providing ammonia as a method product of a method comprising at least the following steps: iii-1-1) Preferably providing hydrogen gas as a product of water electrolysis using electrical energy generated from renewable energy; iii-1-2) Reaction of the provided hydrogen gas with gaseous nitrogen to yield ammonia; iii-2) Reaction of the propene with the provided ammonia to yield acrylonitrile; iv) Synthesis of adiponitrile from acrylonitrile by at least the following steps: Introducing a mixture containing water, the acrylonitrile, and at least one electrolyte salt into the cathode space of an electrolytic cell, and bringing the mixture into contact with the cathode to which an electric current is applied; Cathodic hydrogenation dimerization of acrylonitrile to form an adiponitrile-containing product mixture; Discharge of the adiponitrile-containing product mixture from the cathode space of the electrolytic cell and optional purification of the adiponitrile; v) Synthesis of hexamethylenediamine from acrylonitrile by at least the following steps: Preferably, providing hydrogen gas as a product of electrolysis using electrical energy generated from renewable energy; Hydrogenation of the adiponitrile with hydrogen gas to give hexamethylenediamine; b) Production of phosgene by at least the following method steps: i) CO ２ A method for at least partial reduction of carbon monoxide to CO as a product and / or a method for at least partial oxidation of an organic material to CO as a product, wherein at least one organic material is selected from at least one organic, solid compound, organic, liquid monohydroxyalkyl compound, methane from a biosource or a mixture thereof; ii) Reaction of carbon monoxide from step i) with chlorine to yield phosgene; c) Reaction of the provided hexamethylenediamine with phosgene to give hexamethylene diisocyanate. Methods that include...

2. The carbon monoxide provided in step a) i-1) and / or the carbon monoxide provided in step b) i-1) independently in each case is at least CO ｘ The method according to claim 1, characterized in that it is a method product of at least partial reduction of a gas stream comprising, x = 1 or 2, and which may contain hydrogen gas.

3. The carbon monoxide provided in step a) i-1) and / or the carbon monoxide provided in step b) i-1) are independently, in each case, in particular, H provided by electrolysis. ２ From the reverse water-gas shift reaction using CO ２ Selected from the electrochemical reduction of CO to CO or a mixture thereof, ２ The method according to either claim 1 or 2, characterized in that the product is a method of at least partial reduction of to CO.

4. The carbon monoxide provided in step a) i-1) and / or the carbon monoxide provided in step b) i-1) are, independently in each case, at least H provided by electrolysis. ２ A method of reverse water-gas shift reaction using CO2, or the product of CO2 ２ The method according to any one of claims 1 to 3, provided from the electrochemical reduction of to CO, or from a mixture thereof, wherein in each case, electrical energy generated from renewable energy is used.

5. The method according to any one of claims 1 to 4, characterized in that the conversion of methanol in step a) ii-1) is carried out by contacting the methanol, preferably methanol in the gas phase, with a catalyst.

6. The method according to any one of claims 1 to 5, characterized in that, for the conversion of methanol in step a) ii-1), the provided methanol has a temperature in the range of 200°C to 350°C.

7. The method according to any one of claims 1 to 6, characterized in that the transformation of the starting material by step a) ii-2) is carried out at a temperature of 350°C to 600°C, particularly 380°C to 550°C.

8. The method according to any one of claims 1 to 7, characterized in that the reaction of the provided ammonia with the propene in step a) iii-2) is carried out using oxygen from air at a temperature of 350°C to 550°C.

9. The method according to any one of claims 1 to 8, characterized in that the reaction of the provided ammonia with the propene in step a) iii-2) is carried out on a molybdate and / or antimonate catalyst.

10. The method according to any one of claims 1 to 9, characterized in that the electrolyte salt in the cathode space of the electrolytic cell is selected from at least one quaternary ammonium salt, particularly at least one quaternary ammonium sulfonate.

11. The method according to any one of claims 1 to 10, characterized in that in step a) iv), the electrolytic cell comprises a cathode space and an anode space separated from each other by a membrane.

12. The method according to any one of claims 1 to 11, characterized in that in step a) iv), the introduced mixture has a pH in the range of pH 7 to pH 10, particularly pH 7 to pH 9.

5.

13. The electrolytic cell has a current having a current density of 15 to 40 A / dm passed through the electrolytic cell ２ The method according to any one of claims 1 to 12, characterized in that it has a current having a current density of

14. A method for manufacturing polyurethane, comprising at least the following steps: Production of hexamethylene diisocyanate, a method product of the method according to any one of claims 1 to 13; Providing at least one type of organic polyol; Reaction of the hexamethylene diisocyanate with the polyol to yield polyurethane. Methods that include...

15. The method according to claim 14, characterized in that the provision of the hexamethylene diisocyanate is carried out using the plurality of component system described in claim 16.

16. A plurality of component systems for producing hexamethylene diisocyanate by the manufacturing method described in claims 1 to 13, i) a volume filled with hexamethylenediamine, which is the method product of step a) of the method according to any one of claims 1 to 13; ii) A volume filled with carbon monoxide, which is the method product of step b)i-1) of the method according to any one of claims 1 to 13; iii) At least one electrolytic apparatus for the production of chlorine; iv) at least one reactor for the production of phosgene, the reactor having at least one inlet for chlorine which is fluid-connected to the electrolytic apparatus for the production of chlorine, and at least one inlet for carbon monoxide which is fluid-connected to the volume filled with carbon monoxide; v) At least one reactor for the production of hexamethylene diisocyanate, comprising at least one inlet for phosgene and at least one inlet for hexamethylenediamine, wherein the inlet for phosgene is fluidly connected to the reactor for the production of phosgene, and the inlet for hexamethylenediamine is fluidly connected to the volume of hexamethylenediamine. A multi-component system comprising:

17. Preferably, methanol is used as a raw material for producing hexamethylene radicals of hexamethylene diisocyanate by the method according to any one of claims 1 to 13.

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