Decarbonising of (METH)acrylate preparation

Abstract

The present invention relates to a method for the preparation of a (meth)acrylate in which firstly, a first stream is provided. The first stream contains a hydrocarbon and / or hydrogen. The first stream is reacted with a CO2-containing stream, which is provided by thermal reaction, thereby obtaining a compound having 1 to 4 carbon atoms and 1 to 2 oxygen atoms. This compound is then further reacted to form (meth)acrylate, said reaction comprising the reaction of ethene and / or methanol with a CO-containing stream.

Description

[0001] Decarbonization of (meth)acrylate production

[0002] Description

[0003] Field of the invention

[0004] The present invention relates to a process for producing a (meth)acrylate, in which a first stream is initially provided. The first stream contains a hydrocarbon and / or hydrogen. The first stream is reacted with a CO2-containing stream, which is provided by thermal conversion, to obtain a compound (for example, an organic compound) having 1 to 4 carbon atoms and 1 to 2 oxygen atoms. The organic compound is then further converted to (meth)acrylate, this conversion comprising the reaction of ethene and / or methanol with a CO2-containing stream.

[0005] State of the art

[0006] The global goal is to reduce greenhouse gas emissions in the coming years. In particular, carbon dioxide emissions (CO2 emissions) are to be reduced. Various approaches to reducing greenhouse gas emissions are described in the current state of the art. For example, methods are described for capturing emitted CO2 and converting it into organic compounds that can then be used in industrial processes. A process for capturing and concentrating CO2 in emitted gases and further recycling it is generally referred to as Carbon Capture and Utilization (CCU). Furthermore, processes are described that reduce CO2 emissions in industrial processes through the use of non-fossil fuels, such as biogas.

[0007] For example, Liew et al. (Nature Biotech, Vol. 40, March 2022, pp. 335-344) describe the production of acetone and isopropanol from industrial waste gases through fermentation. In this process, CO2 and hydrogen (H2) from industrial plants are converted into acetone and isopropanol by the bacterium Clostridium autoethanogenum.

[0008] US 7,906,559 B2 describes a process for producing dimethyl ether from CO2 and methane. A 2:1 mixture of hydrogen and CO2 is prepared from water, methane, and CO2 and converted to methanol. The resulting methanol is then dehydrated to yield dimethyl ether.

[0009] US 9,938,225 B2 describes a process for producing methyl methacrylate with a reduced CO2 footprint, whereby the acetone required for the synthesis is produced by fermentation of Ce and Cs sugars. Various processes are known for producing alkyl (meth)acrylates, in particular methyl methacrylate (MMA). The processes usually start from C2, C3, or C4 building blocks. The publication by Nagai et al. ("Trends and Future of Monomer-MMA Technologies", Sumitoma Kagaku 2004-11, January 1, 2004) describes various industrial synthesis routes for producing MMA. The publication by Jaber et al. (“Catalysis for the synthesis of methacrylic acid and methyl methacrylate”, Chemical Society Reviews, Vol. 47, No. 20, 01.01.2018, pp. 7703-7738) also provides an overview of various routes for the production of MMA.In particular, a C4 process for the production of methacrylic acid and suitable catalysts for this purpose are described, in which isobutene is partially oxidized directly to methacrylic acid in one step.

[0010] The production of MMA starting from ethylene via propionaldehyde and methacrolein, with an oxidative esterification of methacrolein with methanol in the last step, is described, for example, in WO 2023 / 059679 A1 and WO 2014 / 116588 A1.

[0011] WO 2014 / 170223 describes a highly efficient process in which propionaldehyde (hereinafter also referred to as propanal) is extracted from C2 fractions in a first step. In a second step, this is reacted with aqueous formaldehyde, i.e., a formalin solution, to form methacrolein. This, in turn, can then be oxidatively esterified to MMA in the presence of special metal or metal oxide catalysts and methanol. This process is also referred to as the LiMA process.

[0012] It is also known to produce MMA in a two-step process. In this so-called alpha process, ethylene, also a C2 fraction, is first methoxycarbonylated to methyl propionate, and the resulting methyl propionate is then reacted with formaldehyde in the gas phase to form MMA. The first step of the process is described, for example, in WO 96 / 19434.

[0013] The processes described in the prior art for the production of (meth)acrylates exhibit relatively high greenhouse gas emissions, particularly CO2 emissions. These result primarily from the reactants used and the energy required to operate the processes. The CO2 footprints and the product carbon footprints (“PCF”) of C3-based MMA processes, the so-called acetone cyanohydrin process, as well as the C2 processes LiMA and ALPHA are published in the specialist literature and elsewhere, for example in “Röhm Group 2022 Non-Financial Declaration”, page 67 “Reducing Greenhouse Gas Emissions and Product Carbon Footprints”, https: / / www.roehm.com / de / nachhaltigkeit?file=files / assets / 01- corporate / downloads / en / Taking%20Responsibility / non-financial-declaration_2022- EN.pdf&cid=6169 (last accessed on August 10, 2023), and in IHS Markit, June 2018, Syed N.Naqvi, Methyl Methacrylate (MMA) Production by Evonik LiMA Process and “Methyl methacrylate (MMA) Eco-profiles and Environmental Product Declarations of the European Plastics Manufacturers” March 2014, https: / / www.petrochemistry.eu / wp-content / uploads / 2018 / 01 / MMA-Eco-profile-EPD-3-14.pdf (last accessed on August 10th 2023).

[0014] Furthermore, the processes only allow for thermal utilization of exhaust gases. The partial recycling of exhaust gases into the processes is not possible or only possible to a very limited extent.

[0015] The publication by Gerby et al. ("Toward economical application of carbon capture and utilization technology with near-zero carbon-emission," Nature Communications, Vol. 13, No. 1, December 5, 2022) describes a CCU (carbon capture and utilization) process in which synthesis gas is obtained by direct electrochemical reduction of carbon dioxide. The "reaction swing absorption" described here initially involves the absorption of carbon dioxide in an amine solution.

[0016] Task

[0017] There was therefore a need for a process for producing (meth)acrylates that does not have, or only to a limited extent, the disadvantages of the processes described in the prior art. In particular, the process should have lower greenhouse gas emissions, especially reduced CO2 emissions, and, if possible, also allow the use, especially the recirculation, of process off-gases.

[0018] A further task was to provide a process in which direct emissions (Scope 1 - CO2 emissions from the MMA process) are reduced as well as Scope 2 and 3 emissions in accordance with the categories of the GHG (Greenhouse Gas) Protocol, an initiative and methodology for the systematic, complete and standardized recording of greenhouse gas emissions, including those from production processes, of the World Resources Institute (WRI), a think tank on environmental protection, and the World Business Council for Sustainable Development (WBCSD), a business association on sustainable development.

[0019] A further task was to find a methyl (meth)acrylate manufacturing process in which direct emissions (Scope 1 emissions) are significantly reduced in accordance with the GHG Protocol and at the same time the CO2 from the direct emissions is used to produce raw materials for an MMA process, which at the same time significantly reduces the dominant Scope 3 upstream emissions.

[0020] Another overarching objective was to specifically reduce the use of fossil raw materials for the production of methyl (meth)acrylates. Solution

[0021] This object was achieved by a process for preparing a (meth)acrylate comprising the following steps a) to f): a) Providing a first stream containing a hydrocarbon of the general formula C nH2n+2, where n is an integer in the range from 1 to 10, and / or hydrogen, b) providing a first process gas containing CO2 by thermally converting a stream from an industrial process, c) separating the CO2 contained in the first process gas by absorbing or adsorbing the CO2 on a medium with subsequent desorption of the CO2 from the medium to obtain a CO2-containing stream, d) mixing the first stream provided in step a) with the CO2-containing stream obtained in step c) to obtain a mixed stream containing the first stream and the CO2-containing stream, e) converting at least a portion of the mixed stream obtained in step d) to obtain a first process stream comprising at least one compound (for example at least one organic compound) containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms,f) reacting at least a portion of the first process stream obtained in step e) to obtain the (meth)acrylate, wherein the reaction in step f) comprises the following steps f1) and f2): f1) reacting ethene and / or methanol with a CO2-containing stream in the presence of a metal catalyst to obtain an organic compound having at least 2 carbon atoms, f2) reacting the organic compound obtained in step f1) with formaldehyde and obtaining the (meth)acrylate.

[0022] The invention preferably relates to a process for producing a (meth)acrylate comprising the following steps a) to f): a) providing a first stream containing hydrogen starting from water, b) providing a first process gas containing CO2 by thermal conversion of a stream from an industrial process, c) separating the CO2 contained in the first process gas by absorption or adsorption of the CO2 on a medium with subsequent desorption of the CO2 from the medium to obtain a CO2-containing stream, d) mixing the first stream provided in step a) with the CO2-containing stream obtained in step c) to obtain a mixed stream containing the first stream and the CO2-containing stream, e) reacting at least a portion of the mixed stream obtained in step d) to obtain a first process stream comprising at least one compound containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms,f) reacting at least a portion of the first process stream obtained in step e) to obtain the (meth)acrylate, wherein the reaction in step f) comprises the following steps f1) and f2): f1) reacting ethene and / or methanol with a CO-containing stream in the presence of a metal catalyst to obtain an organic compound having at least 2 carbon atoms, wherein at least one of the reacted compounds selected from ethene, methanol, and CO-containing stream is the compound obtained in step e) containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms, or is prepared therefrom, f2) reacting the organic compound obtained in step f1) with formaldehyde to obtain the (meth)acrylate.

[0023] A preferred embodiment relates to a process for preparing a (meth)acrylate comprising the following steps a) to f): a) Providing a first stream containing carbon and hydrogen starting from a hydrocarbon of the general formula C nH2n+2, where n is an integer in the range from 1 to 10, b) providing a first process gas containing CO2 by thermally converting a stream from an industrial process, c) separating the CO2 contained in the first process gas by absorbing or adsorbing the CO2 on a medium with subsequent desorption of the CO2 from the medium to obtain a CO2-containing stream, d) mixing the first stream provided in step a) with the CO2-containing stream obtained in step c) to obtain a mixed stream containing the first stream and the CO2-containing stream, e) reacting at least a portion of the mixed stream obtained in step d) to obtain a first process stream comprising at least one compound containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms, f) reacting at least a portion of the first process stream obtained in step e) to obtain the (meth)acrylate,wherein the reaction in step f) comprises the following steps f1) and f2): f1) reacting ethene and / or methanol with a CO2-containing stream in the presence of a metal catalyst to obtain an organic compound having at least 2 carbon atoms, wherein at least one of the reacted compounds selected from ethene, methanol, and CO2-containing stream is the compound obtained in step e) containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms, or is prepared therefrom, f2) reacting the organic compound obtained in step f1) with formaldehyde to obtain the (meth)acrylate. It has surprisingly been found that the process according to the invention has reduced greenhouse gas emissions, in particular reduced CO2 emissions, compared to known processes. This is achieved in particular by utilizing streams from industrial processes. The greenhouse gas emissions are additionally reduced bythat in a preferred embodiment of the invention, streams, in particular also exhaust gases, of the process according to the invention can be recycled into the process according to the invention.,

[0024] The process according to the invention utilizes, in particular, the CO2 emissions, the direct emissions of physical CO2, from a methyl methacrylate process, isolating, concentrating, and conditioning this CO2 for subsequent material use as a carbon building block for the production of C1 to C4 raw materials, which in turn can be used as starting materials for this methyl methacrylate process. The specific use of fossil raw materials per ton of methyl (meth)acrylate is thus significantly reduced, making it possible to transport fewer raw materials. This minimizes the transport risk and also reduces the greenhouse gas emissions associated with transport.

[0025] The process according to the invention is further advantageous because it allows for at least partial utilization of the oxygen stream additionally provided during the splitting of water. This makes it possible, in a preferred embodiment of the invention, to utilize the resulting oxygen stream in the process according to the invention.

[0026] The method according to the invention is described in more detail below.

[0027] In step a) of the process according to the invention, a first stream comprising a hydrocarbon of the general formula C n H2n+2, where n is an integer in the range from 1 to 10, and / or hydrogen.

[0028] The hydrogen contained in the first stream in one embodiment can be provided by processes known to those skilled in the art, for example starting from water. For example, the hydrogen can be provided starting from water by a process selected from the group consisting of coal gasification, steam reforming and water splitting. Preferably, the hydrogen is provided by a process selected from the group consisting of steam reforming and water splitting. In steam reforming, a hydrocarbon, in the simplest case methane or natural gas, is reacted with steam in the gas phase, the resulting hydrogen being composed of the hydrogen atoms of the water and additionally of the hydrogen atoms of the hydrocarbon. If water is split to provide the hydrogen, then hydrogen and an oxygen stream are usually obtained.In addition to the hydrogen, an oxygen stream is provided. The oxygen stream is usually provided separately from the hydrogen.

[0029] The oxygen stream provided can be used in processes known to those skilled in the art in which oxygen is used. For example, the oxygen stream provided can be used in a process selected from the group consisting of the reaction described below in step b), thermal utilization, aerobic wastewater treatment, direct oxidative esterification, and formaldehyde synthesis. The oxygen stream is preferably used in thermal utilization, in particular exhaust gas combustion.

[0030] If the oxygen stream is used in an aerobic wastewater treatment, it is preferably used in the aerobic wastewater treatment according to step b1) described below.

[0031] If the oxygen stream is used in a direct oxidative esterification, this can particularly be the esterification of an aldehyde, such as (meth)acrolein. If the oxygen stream is used in a direct oxidative esterification, it is particularly preferred that it be used for the oxidative esterification of methacrolein to methyl methacrylate in the presence of methanol.

[0032] If the oxygen stream is used in a formaldehyde synthesis, it is preferred that the oxygen stream is used for formaldehyde synthesis starting from methanol by oxidation.

[0033] The splitting of water can then be carried out by methods known to those skilled in the art, for example by electrolysis, electrochemical splitting, or photocatalytic splitting. The splitting is preferably carried out by electrolysis or photocatalytic splitting, particularly preferably by electrolysis.

[0034] These processes are known as such and are described, for example, in IRENA (2020), Green Hydrogen Cost Reduction: Scaling up Electrolysers to Meet the 1.5°C Climate Goal, International Renewable Energy Agency, Abu Dhabi.

[0035] If the splitting is carried out by electrolysis, electricity is typically used for the electrolysis. According to the invention, it is preferred that the electricity used for the electrolysis originate at least partially, preferably entirely, from renewable energies and / or non-fossil energy sources, preferably from renewable energies.According to the invention, therefore, a process is also preferred in which the hydrogen contained in the first stream provided in step a) is provided by electrolysis of water and the electricity used in the electrolysis originates at least partly from renewable energies and / or non-fossil energy sources, wherein in addition to the first stream, an oxygen stream is provided and the oxygen stream provided is used at least partly in at least one process selected from the group consisting of the provision in step b), an aerobic wastewater treatment, a thermal utilization, a direct oxidative esterification and a formaldehyde synthesis.

[0036] For the purposes of this invention, "renewable energies" are understood to mean energy sources for generating electricity that are either self-regenerating or (almost) infinitely available. These are typically characterized by a comparatively low carbon footprint. Renewable energies include, for example, hydropower, wind energy, solar energy, biomass, geothermal energy, and ocean energy. Solar energy includes both photovoltaics and solar thermal energy.

[0037] For the purposes of this invention, "non-fossil energy sources" are energy sources that cannot regenerate themselves and are not available in unlimited quantities, but which are also not based on fossil fuels such as oil or natural gas. Non-fossil energy sources include, in particular, nuclear energy, i.e., nuclear fission and nuclear fusion.

[0038] If the hydrogen in step a) is provided by steam reforming, water is typically reacted with carbon monoxide or carbon monoxide-rich streams in step a). Then, in addition to the hydrogen, a CO2 stream is provided. The steam reforming process is known to those skilled in the art and is described, for example, in Arpe, Industrial Organic Chemistry, 2007, Chapter 2.2.2, pages 27 to 30.

[0039] Carbon monoxide, which is reacted with water in step a), can, for example, originate from industrial plants. This is particularly advantageous because the conversion of carbon monoxide from industrial plants allows the exhaust gases from these plants to be effectively recycled. The CO2 balance of the industrial plants can thus be optimized.

[0040] If the hydrogen is provided in step a) by steam reforming, the additionally provided CO2 stream can, for example, be mixed with the first process gas obtained in step b). The mixed gas obtained in this way can then be fed to step c). It is also possible for the CO2 stream to be subjected to a separation analogous to step c) and for the separated CO2 stream thus obtained to be mixed with the CO2-containing stream. As water from which the hydrogen can be provided in step a), demineralized water is particularly suitable if the hydrogen is provided in step a) by splitting water, in particular by electrolysis of water. If the hydrogen is provided in step a), for example, by steam reforming, process wastewater is particularly suitable, which may, for example, also contain organic components and / or inorganic salts.

[0041] Deionized water is typically provided via a desalination plant. For example, seawater can be passed through a desalination plant to produce deionized water. Likewise, water from an industrial process, in particular water from a process for producing a (meth)acrylate according to step f), most preferably water from a process for producing methyl methacrylate, can be passed through a desalination plant to produce deionized water. It should be noted that reaction water, such as that produced as a by-product of the reaction according to step f), is inherently salt-free; thus, such reaction water does not require special treatment. After separation of organic substances, this water source can, in principle, be used as the input material for electrolysis or steam reforming.

[0042] Furthermore, demineralized water can preferably be provided by a desalination plant that evaporates water using the greenhouse principle. Such desalination plants are known, for example, under the name "solar dorne." These desalination plants are particularly advantageous because they are energy-efficient. Other desalination methods, such as distillation and contact with suitable acidic ion exchangers, are known to those skilled in the art and are used industrially.

[0043] Furthermore, water may be formed during the reaction in step e), especially when methanol is obtained as the organic compound. This water can also be passed through a desalination plant to provide demineralized water.

[0044] If, in a preferred embodiment of the invention described below, converted ethene is provided in step f1) by dehydrating ethanol, water is also formed. This water can be recycled to step a), optionally after being passed through a desalination plant to provide demineralized water. However, it is also possible to use the water formed during the reaction for further use and material utilization, even without desalination.

[0045] The use of water from an industrial process and / or water formed during the reaction in step e) and / or during the dehydration of ethanol makes the process according to the invention particularly efficient, as it additionally saves resources. In a further embodiment, the first stream contains a hydrocarbon of the general formula C nH2n+2, in which n is an integer in the range from 1 to 10. Preferably, n is an integer in the range from 1 to 4. The first stream can contain exactly one hydrocarbon of the general formula C n H2n+2, it is also possible that the first stream contains two or more hydrocarbons of the general formula C n Contains H2n+2.

[0046] The hydrocarbon of the general formula C n H2n+2 is preferably a C1- to C4-hydrocarbon. The hydrocarbon is therefore preferably selected from the group consisting of methane, ethane, propane, and butane, with methane being particularly preferred. Therefore, a process is also preferred in which the first stream provided in step a) contains carbon and hydrogen starting from a C1- to C4-hydrocarbon, preferably methane, and in step e) the first process stream comprises CO as at least one compound.

[0047] As a hydrocarbon of the general formula C n Suitable sources for H2n+2 include natural gas, especially shale gas, methane from coal gasification, and / or methane from renewable sources. Renewable sources from which methane can originate include agriculture and / or biotechnologically produced methane, which is produced from hydrogen and carbon dioxide using archaea. Such sources and methane-containing streams are generally referred to as biogas.

[0048] If the first stream contains the hydrocarbon of the general formula C n H2n+2 and hydrogen, the first stream can be provided, for example, by mixing the hydrocarbon and the hydrogen. It is also possible that the first stream is produced in a biotechnological process described above.

[0049] In step b) of the process according to the invention, a first process gas is produced by thermally converting a stream from an industrial process. The first process gas contains CO2.

[0050] In the context of the present invention, a “thermal conversion” is understood to mean, for example, thermal cracking and / or thermal utilization, such as the combustion of waste gases.

[0051] In step b), a stream from an industrial process is converted. Suitable industrial processes are industrial processes known to those skilled in the art which comprise a stream capable of forming CO2 by thermal conversion. The stream from the industrial process can be obtained, for example, as a by-product stream of the industrial process, as a solvent stream of the industrial process and / or as a reactant stream of the industrial process, optionally with any by-products present therein. It is also possible that a stream from an industrial process is understood to mean that the stream is used, for example, to generate steam in the industrial process and that steam is generated by thermal conversion, forming CO2 in the process. This is particularly the case if the industrial process uses methanol as a reactant, in particular if this is a formaldehyde synthesis or a formalin synthesis.For example, methacrolein can be synthesized from formalin. Likewise, electricity can come from an industrial power generation process.

[0052] The industrial process is preferably selected from the group consisting of synthesis gas production, formic acid production, methyl formate production, oxosynthesis, and a process in which methanol is used as the reactant. Likewise, the industrial process can, for example, comprise a ketonization reaction. In a ketonization reaction, for example, acetic acid is converted to acetone and CO2. Furthermore, the industrial process can, for example, be part of a gas-fired power plant in which CO2 is formed as exhaust gas.

[0053] In the context of the present invention, the term "synthesis gas" refers to a mixture of CO and H2. Processes for producing synthesis gas are known to those skilled in the art. During synthesis gas production, CO2 is typically formed as a byproduct during thermal conversion, which can then be provided as the first process gas in step b).

[0054] Formic acid production and methyl formate production are known as such. They can be produced by processes in which methanol is used as the reactant. In this case, for the purposes of the present invention, formic acid production and methyl formate production are also understood to mean a process in which methanol is used as the reactant. In addition, there are other production processes for formic acid, such as starting from sodium hydroxide and carbon monoxide. In this case, for example, excess carbon monoxide as a stream from an industrial process can be thermally converted to obtain the first process gas containing CO2.

[0055] An oxo synthesis is also referred to as hydroformylation. The preferred oxysynthesis is the hydroformylation of C1-C6 olefins, in particular ethene, propene, 1-butene, and / or 1-octene, most preferably ethene. In oxo synthesis, the C1-C6 olefin is typically reacted with CO and H2 to yield an aldehyde. This aldehyde can then be further converted to an alcohol and / or an acid. The aldehyde produced in the oxo synthesis is preferably propanal. Therefore, it is preferred that the oxo synthesis include propanal production. Another oxo synthesis is the reaction of ethylene with carbon monoxide in the presence of methanol. This so-called carboxymethylation of ethylene is catalyzed by soluble metal salts or organometallic compounds in the additional presence of nitrogen- and / or phosphorus-containing ligands. The reaction yields methyl propionate, an intermediate in the ALPHA MMA process.

[0056] Processes in which methanol is used as a reactant are known as such. A process in which methanol is used as a reactant is preferred, selected from the group consisting of a formaldehyde synthesis, a formaldehyde synthesis, a formalin synthesis and a methyl (meth)acrylate synthesis. A process in which methanol is used as a reactant can also be a methacrolein synthesis. Methacrolein synthesis is usually carried out starting from formaldehyde and / or formalin, which are produced from methanol. Another process in which methanol is used as a reactant can also be a methyl propionate synthesis. Here, methanol is used firstly in the carboxymethylation and in a further step to produce formalin, from which formaldehyde is in turn produced. Formaldehyde is converted to MMA in a gas phase reaction on a heterogeneous catalyst with methyl propionate.These sub-steps describe the sequence of the ALPHA procedure.

[0057] Another process in which methanol is used as a starting material is the production of dimethyl ether (DME) and its further reaction to produce propylene and / or ethylene (also known as the methanol-to-olefin process). These processes are known as such.

[0058] Therefore, a process is also preferred in which the industrial process in step b) is selected from the group consisting of synthesis gas production, formic acid production, methyl formate production, oxosynthesis, formaldehyde synthesis, formalin synthesis, methyl (meth)acrylate synthesis, electricity generation and steam generation.

[0059] After step b) and before step c), the first process gas can be purified.

[0060] A process in which the first process gas is purified after step b) and before step c) is therefore also preferred.

[0061] The purification can be carried out using methods known to those skilled in the art. The purification usually takes place depending on the additional components contained in the first process gas. For example, the first process gas can additionally contain at least one further component selected from the group consisting of SO2, NOx, water, noble gases and oxygen (O2). Processes for separating these additional components and thus for purifying the first process gas are known as such. For example, the separation of SO2 from CO2-containing streams, such as the first process gas, is known as “flue gas desulfurization”. The separation of, for example, NOx and oxygen usually takes place during step c), so that in step c) the first process gas is purified of, for example, NOx and oxygen.

[0062] Preferably, the first process gas is purified after step b) and before step c) to such an extent that the first process gas contains at least 90 vol.% CO2, based on the total volume of the first process gas.

[0063] In step c) of the process according to the invention, the CO2 contained in the first process gas is separated from the first process gas to obtain a CO2-containing stream. The separation occurs by adsorption or absorption of the CO2 on a medium, followed by desorption of the CO2 from the medium. This process step aims to concentrate the CO2-containing stream. Thus, as a result of process step c), a highly concentrated CO2 stream is produced, which can be used as a reactant for further material utilization in the sense of a chemical reaction. CO2 thus becomes a carbon source for higher-value products and, at the same time, no longer enters the atmosphere as a harmful greenhouse gas.

[0064] In the context of the present invention, the term "absorption" refers to the enrichment of a substance within a solid or a liquid. Furthermore, the term "absorption" in the context of the present invention also includes reactive absorption and chemisorption. In particular, in the context of the present invention, the term "absorption" refers to the enrichment of CO2 within the medium when the medium is a solid or a liquid, as described below.

[0065] In the context of the present invention, the term "adsorption" refers to the accumulation of a substance on the surface of a solid. In particular, in the context of the present invention, the term "adsorption" refers to the accumulation of CO2 on the surface of the medium when the medium is a solid in an embodiment described below.

[0066] In the context of the present invention, the terms "absorption" and "adsorption" are also referred to collectively as "sorption." The sorption of CO2 by the medium thus encompasses both the absorption of CO2 by the medium and the adsorption of CO2 by the medium.

[0067] In the context of the present invention, the term "desorption" refers to the reversal of sorption, i.e. the detachment of a substance from the surface of a solid and / or the detachment of a substance from the interior of a solid or a liquid, as well as the decomposition of a thermally unstable compound. In particular, in the context of the present invention, the term "desorption" refers to the detachment of CO2 from the medium. Suitable media include all media known to those skilled in the art that enable the absorption and / or adsorption of CO2. The medium can be a solid, a gas, or a liquid. For example, the medium is selected from the group consisting of mesoporous silicates, metal-organic frameworks (MOFs), zeolites, a basic liquid such as an NaOH solution (sodium hydroxide solution) in water, a basic gas such as ammonia, and a basic solid.Preferably, the medium is selected from the group consisting of zeolites, metal-organic frameworks, a basic liquid and a basic solid, with a basic liquid being particularly preferred.

[0068] Therefore, a process is also preferred in which the medium in step c) is selected from the group consisting of zeolites, metal-organic frameworks, a basic liquid and a basic solid.

[0069] All known zeolites that enable the absorption or adsorption and desorption of CO2 are suitable as zeolites. Zeolites that enable the absorption or adsorption and desorption of CO2 are known as such and are described, for example, in MM Zagho et al., Chemical Engineering Journal Advances 6 (2021) 100091 and US Pat. No. 4,775,396 A. Particularly suitable zeolites for the absorption or adsorption and desorption of CO2 include zeolite A, zeolite ß, and zeolite 13X. Other suitable zeolites are described, for example, in F. Akhtar et al., Energy Environ. Sci. 5 (2012), pp. 7664-7673, and in Q. Liu et al., Chem. Commun. 46 (2010), pp. 4502-4504.

[0070] All known basic liquids that enable the absorption and desorption of CO2 are suitable as basic liquids. Organic basic liquids such as aqueous alkanolamines, especially aqueous triethanolamine, are preferred. If alkanolamines are used as organic basic liquids, this absorption and desorption is also known to those skilled in the art as amine scrubbing. Other suitable basic liquids are described, for example, in DOE / NETL CAPTURE PROGRAM R&D: Compendium of Capture Technology, April 2018. Processes that comprise amine scrubbing followed by regeneration of the carbon dioxide-rich amine according to the absorption-desorption principle are considered to be the preferred method for the separation and concentration of carbon dioxide from flue gases.

[0071] There are also other methods for CO2 capture, such as membrane separation and pressure swing adsorption. The choice of method depends on the specific requirements, application, and cost.

[0072] Suitable basic solids include all known basic solids that enable the absorption or adsorption and desorption of CO2. Organic basic solids are preferred. Suitable basic solids are described, for example, in DOE / NETL CAPTURE PROGRAM R&D: Compendium of Capture Technology, April 2018.

[0073] All known metal-organic frameworks that enable the absorption, adsorption, and desorption of CO2 are suitable. Metal-organic frameworks are also referred to as metal-organic frameworks (MOFs). Suitable metal-organic frameworks are described, for example, in Surendar R. Venna, Moises A. Carreon, Chem Eng. Sci., 2015, 124, pages 3 to 19, and in J.R. Lon et al., Chem. Rev., 2012, 112, 2, 724-781.

[0074] The absorption or adsorption of CO2 by the medium can be carried out using methods known to those skilled in the art. For example, the first process gas is passed through the medium, whereby CO2 from the first process gas is absorbed or adsorbed by the medium.

[0075] Typically, the absorption or adsorption of CO2 by the medium occurs at a first temperature. The first temperature can be arbitrary. For example, the first temperature is in the range of -50 °C to 100 °C, preferably in the range of 0 °C to 50 °C.

[0076] The desorption of CO2 from the medium typically occurs at a second temperature. The second temperature can be arbitrary. Typically, the second temperature is below the decomposition temperature of the medium. For example, the second temperature is in the range of 20 °C to 250 °C, preferably in the range of 60 °C to 150 °C.

[0077] Therefore, a process is also preferred in which the adsorption or absorption in step c) takes place at a first temperature in the range from 0 °C to 50 °C and / or in which the desorption in step c) takes place at a second temperature in the range from 60 °C to 150 °C.

[0078] According to the invention, it is preferred that the difference between the second temperature and the first temperature is greater than 20 °C, preferably greater than 50 °C. If the medium is or contains an organic medium, for example an organic basic liquid or an organic basic solid, the difference between the second temperature and the first temperature is usually less than 200 °C.

[0079] It goes without saying that the first temperature is different from the second temperature. It is also clear to those skilled in the art that the absorption or adsorption of CO2 by the first medium and the desorption of CO2 from the medium represent an equilibrium. The first temperature therefore describes a temperature at which absorption or adsorption dominates desorption and the equilibrium is shifted toward absorption or adsorption. In contrast, the second temperature describes a temperature at which desorption dominates absorption or adsorption and the equilibrium is shifted toward desorption.

[0080] Additionally or alternatively, the separation in step c) may comprise absorption of CO2 on a membrane, preferably under cryogenic conditions below 0 °C. Cryogenic processes or conditions are used when the CO2-containing feed stream is already pre-concentrated prior to the sorption process, for example, has a CO2 content of 50 vol% or higher.

[0081] The separation of CO2 on a membrane, preferably under cryogenic conditions, is known as such and is described, for example, in DOE / NETL CAPTURE PROGRAM R&D: Compendium of Capture Technology, April 2018 and Delphine Pichot et al., Energy Procedia 114 (2017), 2682- 2689.

[0082] The separation in step c) produces a CO2-containing stream. This CO2-containing stream consists primarily of CO2. Furthermore, the CO2-containing stream may contain residues of other components. One such additional component is water.

[0083] “Consists essentially of CO2” in the context of the present invention means that the CO2-containing stream contains more than 90 vol.%, preferably more than 95 vol.% and particularly preferably more than 99 vol.% CO2, based on the total volume of the CO2-containing stream.

[0084] The CO2-containing stream is preferably substantially free of oxygen (O2). For example, the CO2-containing stream preferably contains at most 0.01 vol.% oxygen, particularly preferably at most 0.001 vol.% oxygen, in each case based on the total volume of the CO2-containing stream. The oxygen content of the concentrated, resulting CO2 stream is relevant when processes are used in subsequent steps in which the oxygen content must be critically controlled or has a detrimental effect on the subsequent reaction. This is the case when CO2 is used as a reactant in a methanol synthesis; it is also critical if fermentative production of, for example, acetone or ethanol is planned.

[0085] In step d) of the process according to the invention, the first stream provided in step a) is mixed with the CO2-containing stream obtained in step c). A mixed stream is obtained that contains the first stream and the CO2-containing stream.

[0086] The first stream can be mixed with the CO2-containing stream using methods known to those skilled in the art. Preferably, the CO2-containing stream is compressed before or during mixing with the first stream. This allows any water present in the CO2-containing stream to be removed. Furthermore, it is possible to deoxygenate the mixed stream. The deoxygenation, preferably adiabatic deoxygenation, can be carried out by contacting the mixed stream with a transition metal catalyst and / or a noble metal catalyst at a temperature in the range of 200°C to 400°C. Analogously, the CO2-containing stream and / or the first stream can also be deoxygenated before mixing the CO2-containing stream with the hydrogen stream.

[0087] The volume ratio of the first stream to the CO2-containing stream in step d) is, for example, in the range from 1 to 1 to 10 to 1, preferably in the range from 1 to 1 to 4 to 1.

[0088] Therefore, a process is also preferred in which the volume ratio of the first stream to the CO2-containing stream in step d) is in the range from 1 to 1 to 4 to 1.

[0089] If step b1) described below is additionally carried out, it is possible according to the invention that in step d) at least parts of the third process gas or optionally CO2 separated from the third process gas are additionally mixed with the first stream and the CO2-containing stream to obtain the mixed stream which then additionally contains at least parts of the third process gas.

[0090] It is also possible to mix the CO2 stream provided in step a) in the case of steam reforming at least partially with the first stream and the CO2-containing stream in step d) to obtain the mixed stream which then additionally contains at least parts of the CC>2 stream.

[0091] In step e), the mixed stream obtained in step d) is reacted to obtain a first process stream. The first process stream comprises at least one compound, for example at least one organic compound, containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms.

[0092] The first process stream comprises at least one compound, for example at least one organic compound containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms. Furthermore, the first process stream may comprise additional components.

[0093] The additional components that may be contained in the first process stream usually depend on the type of reaction in step e).

[0094] In the context of the present invention, "at least one compound" means both precisely one compound and a mixture of two or more compounds. In the context of the present invention, "at least one organic compound" means both precisely one organic compound and a mixture of two or more organic compounds.

[0095] The at least one compound, for example the at least one organic compound, contains 1 to 4 carbon atoms and 1 to 2 oxygen atoms. The at least one compound, for example the at least one organic compound, is therefore preferably selected from the group consisting of CO, formaldehyde, methanol, formic acid, acetaldehyde, ethanol, ethylene glycol, acetic acid, acetone, propanal, propanol, 1-isopropanol, propanediol, isobutanol, and tert-butanol, preferably selected from the group consisting of CO, methanol, ethanol, 1-propanol, isobutanol, and tert-butanol, particularly preferably selected from the group consisting of CO, methanol, and ethanol.

[0096] Therefore, a process is also preferred in which the at least one compound, for example the at least one organic compound, of the first process stream is selected from the group consisting of CO, methanol, ethanol, 1-propanol, isobutanol and tert-butanol.

[0097] Suitable reactions in step e) include all reactions that enable the production of a first process stream comprising at least one compound, for example the at least one organic compound, from the mixed stream according to the invention. The reaction can be carried out in one or more stages.

[0098] For example, the reaction in step e) can be carried out fermentatively or in the presence of a catalyst.

[0099] A process in which the reaction in step e) is carried out fermentatively or in the presence of a catalyst is therefore also preferred.

[0100] If the reaction in step e) is carried out in the presence of a catalyst, it is preferred that the mixed stream be converted in the gas phase over a heterogeneous catalyst. A copper / zinc / aluminum oxide catalyst is particularly preferred as the catalyst. Preferably, the at least one compound, for example the at least one organic compound, comprises methanol and / or CO. Water is also typically formed as an additional component during the reaction.

[0101] In one embodiment, it is preferred that the reaction takes place at a pressure in the range from 20 to 120 bar and a temperature in the range from 130°C to 350°C. The first process stream then typically comprises at least methanol as at least one compound, in particular as at least one organic compound, and water. Typically, in this reaction, in addition to methanol as at least one compound or organic compound, ethanol, dimethyl ether, and / or methyl formate are additionally formed as at least one compound or organic compound. Ketones and / or olefins can then also be formed as additional components.

[0102] Therefore, a process is also preferred in which the reaction in step e) comprises a reaction of the mixed stream in the gas phase on a heterogeneous contact, the reaction taking place at a pressure in the range from 20 to 120 bar and a temperature in the range from 130 °C to 350 °C, the resulting first process stream comprising methanol and water.

[0103] It is further preferred that, in this embodiment, the obtained first process stream is at least partially condensed following step e) to obtain an aqueous phase, a methanol-containing phase, and a second process stream. The second process stream is preferably uncondensed and is therefore in gaseous form. The aqueous phase and the methanol-containing phase are preferably in liquid phase.

[0104] In this embodiment, the methanol-containing phase is then converted as the first process stream in step f).

[0105] In this embodiment, it is further preferred that the second process stream is mixed with the first process stream and is reacted in step e), wherein the reaction in step e) takes place in a plurality of partial reactors passed through in series, preferably tube bundle reactors and / or tray reactors, wherein a partial conversion of between 20% and 90% is achieved in the respective partial reactors and wherein the gas mixture obtained during the reaction in the respective partial reactors is cooled before entering the next partial reactor.

[0106] In a further embodiment, it is preferred that the reaction in step e) takes place in a single reactor, preferably an adiabatic reactor.

[0107] In a further embodiment, it is preferred that the reaction in step e) takes place at a temperature in the range from 300°C to 700°C. The first process stream then typically comprises at least CO as at least one compound and water.

[0108] Furthermore, the conversion in step e) can also be carried out electrochemically, for example. For example, the mixed stream can be converted electrochemically to obtain a first process stream comprising CO as at least one compound containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms.

[0109] If methanol is initially formed as a compound, particularly an organic compound, in step e), it can be further converted. For example, methanol can be further converted to dimethyl ether and water. Dimethyl ether can then be further converted to propene, which reacts with CO and H2 to form isobutanol. Isobutanol can then be further converted to tert-butanol. These processes are known as such.

[0110] If the reaction in step e) is carried out fermentatively, the reaction usually takes place microbially or enzymatically. "Microbial" in the context of the present invention means that the reaction takes place in the presence of bacterial cultures, fungal cultures, or other cell cultures, preferably in the presence of bacterial cultures. Such bacterial cultures are described, for example, in Liew et al. (Nature Biotech, Vol. 40, March 2022, pp. 335-344).

[0111] If the reaction in step e) is carried out fermentatively, the at least one compound, in particular the at least one organic compound, preferably comprises at least one compound selected from the group consisting of acetone, ethanol and propanol.

[0112] If the first stream and thus the mixed stream contains a hydrocarbon of the general formula C n If the hydrocarbon contains H2n+2, in particular methane, step e) preferably first comprises a cleavage of the hydrocarbon, forming carbon and hydrogen. These are then reacted with the CO2-containing stream to obtain the at least one compound.

[0113] Also preferred is an embodiment in which the first stream and thus the mixed stream comprises carbon and hydrogen starting from a hydrocarbon of the general formula C n H2n+2, where n is an integer in the range from 1 to 10, a hydrocarbon of the general formula C nH2n+2, in particular methane, and step a) initially comprises a cleavage of the hydrocarbon, forming carbon and hydrogen. These are then mixed with the CO2-containing stream in step d) and reacted in step e) to obtain the at least one compound containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms, preferably to obtain CO as the at least one compound. A process for the cleavage of hydrocarbons of the general formula C n H2n+2 in a plasma reactor into carbon and hydrogen and the subsequent production of synthesis gas by reaction with CO2 is known to the person skilled in the art and is described, for example, in WO 2022 / 053647 A1.

[0114] Following step e) and before step f), the resulting first process stream can be purified.

[0115] Therefore, a process is also preferred in which the first process stream obtained in step e) is purified after step e) and before step f).

[0116] The first process stream can be purified using known methods. For example, the first process stream can be purified by distillation. Furthermore, the first process stream can be filtered for purification, for example, to remove bacterial cultures.

[0117] It is also possible for the first process stream to be subjected to deoxygenation as a purification step, preferably an adiabatic deoxygenation in contact with a transition metal catalyst and / or noble metal catalyst at a temperature in the range of 200 °C to 800 °C.

[0118] In step f), at least a portion of the first process stream obtained in step e) is reacted to obtain the (meth)acrylate. The reaction comprises the following steps f1) and f2): f1) reacting ethene and / or methanol with a CO-containing stream in the presence of a metal catalyst to obtain an organic compound having at least 2 carbon atoms, f2) reacting the organic compound obtained in step f1) with formaldehyde to obtain the (meth)acrylate.

[0119] The implementations in steps f1) and f2) can each be single-stage or multi-stage.

[0120] In step f1), ethene and / or methanol is reacted with a CO-containing stream in the presence of a metal catalyst.

[0121] The reaction of ethylene and / or methanol with a CO2-containing stream in the presence of a metal catalyst is known per se. It is described, for example, in Industrial Organic Chemistry, Chapter 6.1.4 Catalytic Variants of Hydroformulation and Chapter 7.4.1.3 Carbonylation of Methanol to Acetic Acid. An example of the reaction of methanol with a CO2-containing stream in the presence of a metal catalyst is the Monsanto process for producing acetic acid, which is familiar to those skilled in the art.

[0122] For the purposes of the present invention, a "metal catalyst," preferably a "transition metal catalyst," is understood to mean a catalyst that contains a metal, preferably a transition metal. Suitable metal catalysts are metal catalysts known to those skilled in the art that catalyze the reaction of the CO-containing stream with ethene and / or methanol. Transition metal catalysts, in particular metal-carbonyl complexes, are preferred, where the metal is selected from the group consisting of nickel, cobalt, rhodium, and iridium. Furthermore, the metal catalyst is preferably a homogeneous catalyst. Preference is given to a palladium-containing catalyst.

[0123] The ethene used can originate from any source. Ethene is preferably produced by dehydrating ethanol. It is further preferred that in step e), the at least one organic compound comprises ethanol, which is dehydrated to ethene after step e) and before step f).

[0124] According to the invention, therefore, a process is also preferred in which the at least one compound obtained in step e), in particular the at least one organic compound, comprises ethanol and in which ethene converted in step f1) is provided by dehydration of the ethanol obtained in step e).

[0125] It is also possible to produce ethylene by dehydrating ethanol, whereby ethanol is produced from biomass, for example, corn. Ethanol produced from biomass is also referred to as bioethanol. Particularly preferred is the production of the ethanol from CO2 itself, especially using the Scope 1 emissions from the methacrylate process or its precursors. If ethanol is produced from biogenic materials, the use of secondary or second-generation biomass is a preferred embodiment. This ensures that the ethanol used has a significantly reduced carbon footprint.

[0126] Secondary biomass refers to organic materials derived from waste, byproducts, or residues that can be reused or converted in biologically based processes. Unlike primary biomass, which is derived from plants, animals, and other biological sources, secondary biomass is produced as a result of human activities or industrial processes.

[0127] Examples of secondary biomass can be:

[0128] 1. Biogenic waste: Plant residues, agricultural by-products, green waste, food scraps, and animal manure can be considered secondary biomass. These materials can be used in biogas plants to generate biogas or produce fertilizers.

[0129] 2. Byproducts and residues: Some industrial processes, such as wood processing or food production, generate byproducts and residues. These could be used for energy generation, the production of bio-based products, or soil improvement.

[0130] 3. Waste materials: Sewage sludge, organic waste from wastewater treatment plants or landfills can be considered secondary biomass because they contain organic materials that can potentially be recycled or utilized in environmentally friendly processes.

[0131] 4. Industrial side streams: In the food or paper industry, side streams such as fruit residues or waste paper can serve as secondary biomass when used in bioenergy plants or for the production of bioproducts. The use of secondary biomass can offer multiple benefits, including waste reduction, conservation of primary resources, energy generation, and reducing the environmental impact of certain industrial processes. Converting secondary biomass into valuable products or energy contributes to promoting the circular economy and sustainability.

[0132] Furthermore, it is possible and preferred according to the invention for ethene to be produced from methanol by a so-called "methanol to olefins" process. In this embodiment, it is preferred that in step e), the at least one compound, in particular the at least one organic compound, comprises methanol, and this methanol is at least partially subjected to the methanol to olefins process.

[0133] If methanol is reacted in step f1) in addition to or as an alternative to ethene, it is preferred that in this embodiment in step e) the at least one compound, in particular the at least one organic compound, comprises methanol and this methanol is then reacted in step f1).

[0134] Therefore, a process is also preferred in which the at least one organic compound obtained in step e) comprises methanol and is used as methanol in step f1).

[0135] As a CO2-containing stream in step f1), for example, a stream, in particular an exhaust gas stream, from an industrial process can be used.

[0136] It is also possible and preferred according to the invention that the at least one compound obtained in step e) comprises CO. This can then be used in step f1) as a CO-containing stream.

[0137] Therefore, a process is also preferred in which the at least one compound obtained in step e) comprises CO and is used in step f1) as a CO-containing stream.

[0138] In step f1), additional components can optionally be reacted. One such additional component is propyne, for example. For example, methanol and propyne can be reacted with the CO-containing stream in the presence of a metal catalyst to form methyl methacrylate.

[0139] In step f1), an organic compound having at least 2 carbon atoms is obtained. It goes without saying that the organic compound having at least 2 carbon atoms is formed during the reaction of ethene and / or methanol with the CO-containing stream and any reacted further component in the presence of the metal catalyst. The organic compound having at least 2 carbon atoms preferably additionally comprises 1 to 2 oxygen atoms. Furthermore, the organic compound preferably comprises 2 to 5 carbon atoms and 1 to 2 oxygen atoms.

[0140] For example, the organic compound having at least 2 carbon atoms is selected from the group consisting of acetic acid, methyl acetate, propanal, propionic acid, methyl propionate, and methyl methacrylate. Preferably, the organic compound having at least 2 carbon atoms is selected from the group consisting of acetic acid, methyl acetate, propanal, propionic acid, and methyl propionate, and particularly preferably selected from the group consisting of propanal and methyl propionate.

[0141] Therefore, a process is also preferred in which the organic compound having at least 2 carbon atoms obtained in step f1) is selected from the group consisting of acetic acid, methyl acetate, propanal, propionic acid and methyl propionate.

[0142] In step f2), the organic compound obtained in step f1) is reacted with formaldehyde and the (meth)acrylate is obtained.

[0143] The reaction in step f2) can be single- or multi-stage. For example, in a single-stage reaction, the (meth)acrylate can be obtained directly by reacting the organic compound with formaldehyde. It is also possible that in a two-stage reaction, an intermediate product is initially obtained by reacting the organic compound with formaldehyde, which is then further converted to the (meth)acrylate.

[0144] The reaction of the organic compound with formaldehyde is known per se. The reaction can be carried out, for example, in the presence of a catalyst and / or an additional component. Suitable catalysts are known and are described, for example, in EP 3 841 084 A1 and EP 3 194 355 A1. Suitable additional components are also known.

[0145] For example, when the organic compound is reacted with formaldehyde, (meth)acrolein is obtained as an intermediate.

[0146] For example, (meth)acrolein is obtained as an intermediate when propanal is reacted as an organic compound with at least 2 carbon atoms.

[0147] The formed (meth)acrolein can then be further converted, for example, in the presence of oxygen and methanol, to the (meth)acrylate, in particular to methyl methacrylate. Therefore, a process in which (meth)acrolein is first formed during the reaction in step f2) and then further converted to the (meth)acrylate is also preferred.

[0148] For example, the organic compound obtained in step f1) is reacted with formaldehyde and ethylene and methyl propionate is obtained as an intermediate.

[0149] For example, in step f1), propionic acid methyl ester is obtained as an organic compound having at least 2 carbon atoms when methanol is reacted with CO and ethylene.

[0150] Propionic acid methyl ester can then be further converted to methyl methacrylate in step f2), for example in the presence of formaldehyde.

[0151] Therefore, a process is also preferred in which, in the reaction in step f1), propionic acid methyl ester is first formed as an organic compound having at least 2 carbon atoms, which is then further converted to the (meth)acrylate in step f2).

[0152] If in step a) the first stream contains hydrogen and the hydrogen is provided by electrolysis of water, then, for example, additionally provided oxygen stream can be used as oxygen for the conversion of (meth)acrolein to the (meth)acrylate.

[0153] For example, (meth)acrylic acid is obtained as (meth)acrylate when propionic acid is reacted as an organic compound with at least 2 carbon atoms.

[0154] The formaldehyde converted in step f2) can be prepared by methods known to those skilled in the art. Formaldehyde is preferably prepared starting from methanol. In particular, the at least one compound obtained in step e), in particular at least one organic compound, preferably comprises methanol, which is converted to formaldehyde and then used in step f2).

[0155] Therefore, a process is also preferred in which the at least one compound obtained in step e), in particular at least one organic compound, comprises methanol and is used as methanol in step f1) and / or is converted to formaldehyde and then used in step f2).

[0156] In step f), the (meth)acrylate is obtained. For the purposes of the present invention, the term "(meth)acrylate" refers to C1-C18 alkyl (meth)acrylates and (meth)acrylic acid.

[0157] The term "(meth)acrylic acid" in the context of the present invention refers to both acrylic acid and methacrylic acid. The term "Ci-Ci8-alkyl (meth)acrylate" in the context of the present invention refers to alkyl esters of (meth)acrylic acid having 1 to 18 carbon atoms in the alkyl radical. The alkyl radical may also contain heteroatoms within the alkyl radical and / or be substituted by heteroatoms and, in particular, contain hydroxyl groups (OH groups). The alkyl radical may be cyclic or linear, and branching is also possible.

[0158] The (meth)acrylate is therefore, for example, selected from the group consisting of methyl (meth)acrylate, ethyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, ethylhexyl (meth)acrylate, isopropyl (meth)acrylate and (meth)acrylic acid.

[0159] If isobutanol is obtained as at least one organic compound in step e), this can be used, for example, for the transesterification of the (meth)acrylate obtained in step f2).

[0160] Furthermore, in one embodiment of the process according to the invention, it is possible for isobutanol and / or tert-butanol to be converted to isobutene in step f). This can then be converted in the presence of oxygen (O2) to methacrolein, which is then further converted to the (meth)acrylate. In this embodiment, step f) does not include steps f1) and f2).

[0161] Therefore, a process is also preferred in which, in step f1), the CO-containing stream is reacted with hydrogen and ethylene in a hydroformylation reaction to form propanal as an organic compound having at least 2 carbon atoms, and in step f2), the propanal is reacted with formaldehyde to form methacrolein, wherein, in a further step, methacrolein is reacted in the presence of an oxygen-containing gas to form methacrylic acid and / or methacrylic acid ester.

[0162] The process according to the invention may comprise further steps in addition to steps a) to f).

[0163] For example, the process according to the invention can additionally comprise the following steps a1) and a2): a1) providing a second process gas which contains hydrogen by oxidative dehydrogenation of methanol, a2) mixing the first stream which contains hydrogen provided in step a) and the second process gas provided in step a1) to obtain a hydrogen mixed stream, wherein in step d) the hydrogen mixed stream obtained in step a2) is then mixed with the CO2-containing stream obtained in step c).

[0164] The oxidative dehydrogenation of methanol is known per se to those skilled in the art. Typically, the oxidative dehydrogenation of methanol occurs with oxygen in the presence of a catalyst, for example, a silver catalyst. Formaldehyde and hydrogen are formed. This process is described, for example, in EP 0 624 565 A1 and Industrial Organic Chemistry, Chapter 2.3.2.1 Formaldehyde from Methanol.

[0165] If the hydrogen is provided by electrolysis in step a), the additional oxygen stream provided can be used, for example, as oxygen for the oxidative dehydrogenation of methanol in step a1).

[0166] The second process gas provided in step a1), which contains hydrogen, can optionally be purified after step a1) and before step a2). Methods for this are known per se.

[0167] The process gas provided in step a1) is then mixed, optionally after purification, with the hydrogen provided in step a2) in step a2), resulting in a mixed hydrogen stream.

[0168] In this embodiment, in step d), the hydrogen mixed stream obtained in step a2) is typically mixed with the CO2-containing stream obtained in step c). The previously described embodiments and preferences for step d), in which the first stream provided in step a) is mixed with the CO2-containing stream, apply accordingly to the case where in step d), the mixed stream obtained in step a2) is mixed with the CO2-containing stream.

[0169] The mixed hydrogen stream can be purified after step a2) and before step d). Methods for this are known.

[0170] Preferably, the hydrogen mixed stream is purified to such an extent that the hydrogen mixed stream contains more than 95 vol.% hydrogen, based on the total volume of the hydrogen mixed stream.

[0171] The method according to the invention may also comprise, for example, the following step b1): b1) Providing a third process gas containing CO2 by aerobic

[0172] Wastewater treatment, wherein the CO2 contained in the third process gas is separated following step b1), if appropriate analogously to step c).

[0173] A process is therefore preferred in which the process additionally comprises the following step b1): b1) providing a third process gas containing CO2 by aerobic wastewater treatment, wherein the CO2 contained in the third process gas is separated following step b1), optionally analogously to step c).

[0174] Aerobic wastewater treatment is known as such.

[0175] Preferably, the CO2 contained in the third process gas provided in step b1) is separated following step b1) in a manner analogous to the CO2 contained in the first process gas provided in step b). The embodiments and preferences described for step c) therefore apply accordingly to the separation of the CO2 from the third process gas.

[0176] It is also possible for the first process gas and the third process gas to be mixed before step c) and for a process gas mixture to be obtained from which the CO2 can then be separated in step c).

[0177] By way of example, some reaction routes according to the invention with regard to process steps e) and f) are shown below:

[0178] In a first exemplary variant of the process according to the invention, the at least one compound, in particular the at least one organic compound, in step e) is ethanol. This is first dehydrogenated to ethylene and then converted to propanal as an organic compound in a hydroformulation reaction with CO and hydrogen according to step f1). Finally, propanal is reacted with formaldehyde in step f2) to form methacrolein, which can be oxidatively esterified to MMA or oxidized to methacrylic acid and optionally subsequently esterified to MMA.

[0179] In a second exemplary variant of the process according to the invention, in step e) the at least one compound, in particular the at least one organic compound, is methanol, which can be reacted with ethylene and CO in step f1) to form propionic acid methyl ester and subsequently in step f2) with formaldehyde to form MMA.

[0180] In a third exemplary variant of the process according to the invention, the at least one compound, in particular the at least one organic compound, in step e) is ethanol, which can be converted to ethylene. This ethylene can then be converted with methanol and CO in step f1) to methyl propionate and subsequently with formaldehyde in step f2) to MMA.

[0181] In a fourth exemplary variant of the process according to the invention, the at least one compound in step e) is CO, which can be reacted with hydrogen, ethylene, and methanol in step f1) to form propionic acid methyl ester and then with formaldehyde in step f2) to form MMA. In a fifth exemplary variant of the process according to the invention, the at least one compound in step e) is CO, which is reacted with hydrogen and ethylene in step f1) to form propanal in a hydroformulation reaction. This propanal can then be reacted with formaldehyde in step f2) to form methacrolein, wherein the methacrolein can be oxidatively esterified to MMA or oxidized to methacrylic acid and optionally subsequently esterified to MMA.

[0182] In a sixth exemplary variant of the process according to the invention, the at least one compound, in particular the at least one organic compound, in step e) is MeOH, which is reacted with CO in step f1) to form methyl acetate. This methyl acetate is then reacted with formaldehyde in step f2) to form methyl acrylate, wherein the methyl acrylate is reacted with H2 to form propionic acid. Propionic acid can then be further reacted to MM A as described above.

[0183] Examples

[0184] The following examples were calculated using the process simulation software Aspen Plus version 1.1. The process steps described in the individual examples and comparative examples were used as the basis for the calculations.

[0185] To estimate indirect CO2 emissions, typical CO2 factors for raw materials,

[0186] Fuels and electricity from databases such as PlasticsEurope or other commercially available

[0187] Databases (Ecoinvent, Sphera, etc.) as well as the US EIA energy database (www.eia.gov) for the Gulf Coast of the USA were used. Specifically, for electricity, a

[0188] Carbon intensity of 0.52 kgCO2e / kWh was chosen, which roughly corresponds to a typical average value in this region between 2018 and 2021.

[0189] Methanol 0.7 kgCC>2.eq / kg_Methanol

[0190] Ethylene 1.8 kgCO2,aq / kg_ethylene

[0191] Syngas (1:1) 0.91 kgCO2,aq / kg_Syngas

[0192] Natural gas 0.52 kgCO2,aq / kg_natural gas

[0193] A summary of the results on CO2 emissions and the Product Carbon Footprint (PCF) for the different examples is shown in Tables 1 and 2.

[0194] Comparison example V1

[0195] MMA production based on methanol, ethylene and synthesis gas

[0196] The following example describes a conventional C2 MMA synthesis from methanol, ethylene, and synthesis gas with a capacity of 250 kta. Conventional in this context refers to the use of fossil feedstocks based on crude oil and natural gas and the resulting product carbon footprints (PCFs) of the described process. Process step 1: Propionaldehyde synthesis (step f1)

[0197] According to the general state of the art in hydroformulation (cf. e.g. Chemical Engineering, December 1977, p. 110 ff), ethylene is fed together with synthesis gas (H2:CO ratio of 1:1) into a reactor filled with a catalyst consisting of rhodium and phosphane ligands dissolved in the liquid phase (e.g. Wilkinson catalyst). For the calculations and the simulation and calculation of consumption factors, triphenylphosphane was used as the ligand, as well as an additional gas stream consisting of hydrogen to maintain the activity of the Wilkinson catalyst as far as possible. At 110°C and 16 bar, crude propionaldehyde is fed in gaseous form from the reactor without cooling or expansion to the level of the 6th plate of a packed column with a total of 8 theoretical plates and fractionated there (analogous to EP 0 062282 B1).At the top of the column, the overhead product is first cooled to 40°C at 90°C, then gaseous components (mainly CO, H2, ethylene, and ethane) are separated out, and the liquid phase is returned to the column. 0.61 t / h of the gas phase is discharged as offgases, and the remainder, 17 t / h, is recycled to the reactor via a compressor (differential pressure 2 bar) as cycle gas together with fresh gas, i.e., ethylene and synthesis gas. At the bottom of the column, a crude propionaldehyde stream of 20.4 t / h containing 0.1 wt.% ethylene and 0.8 wt.% propanol and higher-boiling components is obtained at 153°C. The offgas is fed to a thermal afterburner (process step 5) and burned there. High-boiling components such as pentenals and pentanals are subsequently depleted from the crude propionaldehyde stream to obtain propionaldehyde (“PA”).The specific input factors of the described process (as a basis for calculating the PCF) are 0.495 tons% ethylene / ton PA and syngas 1:1 CO / H2 870 Nm per ton of propionaldehyde. 3 / ton% PA. The following auxiliaries and catalysts are taken into account per ton% PA: 25 mg rhodium, 10 kg TPP (triphenylphosphine) and 15 Nm 3 Hydrogen. The energies considered in the PCF calculations as Scope 2 emissions according to the Greenhouse Gas Protocol were determined as follows (all figures are specific per ton% PA): 0.9 tons of steam, 100 kWh of electricity, 10 kg of organic waste for thermal recycling, and a gas discharge with a calorific value of 0.2 MWh.

[0198] The purity of propionaldehyde is > 99.5 wt%

[0199] Process step 2: Formalin production

[0200] The process used and simulated largely corresponds to the published parameters of FASIL™ OPERATIONAL COSTS https: / / dynea.com / technology-sales / new-formaldehyde- plants / fasil-operational-costs / last accessed on August 10, 2023.

[0201] For the given MMA capacity, 12.5 t / h of methanol are used to produce formaldehyde. The methanol is first evaporated and heated to 80°C before being fed into the reactor with air and reacted with a multi-stage layer of silver crystals of various grain sizes at nearly 650°C. The reactor inlet stream comprises 53.3 t / h. After initial cooling, the gaseous reactor product has a temperature of 250°C and contains 43 vol% N2, 26 vol% H2O, 16 vol% formaldehyde, 10 vol% H2, 3% CO2, 0.5% MeOH, and traces of O2 and CO. The reactor product is then fed into a desorber column, where it is cooled by a water quench. Volatile components pass through the top of the column and are recycled to the reactor via a cycle gas compressor at a mass flow rate of 11.8 t / h. This recycle stream contains 73 vol% N2, 16% H2, 5 vol% CO2, 4 vol% H2O, 0.2 vol% MeOH, and traces of formaldehyde, CO, and O2.The stream temperature is 31 °C. To prevent the accumulation of inert substances, a continuous discharge of 20.4 t / h is removed and combusted together with air in the thermal afterburner (process step 5). This results in 2.14 t / h of CO2 emissions. In the lower part of the desorber column, the formalin product is removed at 89 °C. It contains 55 wt% formaldehyde, 44 wt% H2O, 0.7 wt% MeOH, and traces of dissolved gases (H2, N2, O2, CO). The total mass flow is 18.8 t / h.

[0202] The specific input factors of the described process (as the basis for calculating the PCF) are 1.21 tons% methanol / ton of FA per ton of formaldehyde, as well as compressed air in a specific quantity of 37 Nm3 per ton% of FA. 2.2 tons of boiler feed water per ton% of FA are considered as auxiliary materials. The following was determined for the energies considered in the PCF calculations as Scope 2 emissions according to the Greenhouse Gas Protocol (all figures specific per ton% of FA): Steam export: minus 2.2 tons of steam, 95 kWh electricity, 70 m 3 Cooling water requirement; organic waste was not considered due to its minimal amount and thus minimal impact on the PCF. The formalin content, i.e., the concentration of formaldehyde as an aqueous solution, is 55 wt%.

[0203] Process step 3: Methacrolein (MAL) synthesis (part of step f2)) Formalin product from process step 2 is then mixed with 20.4 t / h of propionaldehyde from process step 1 and converted into methacrolein together with 965 kg / h of dimethylamine (DMA) (composition: 40 wt.% DMA and 60 wt.% H2O) and 80% acetic acid at a mass flow of 710 kg / h at 30 bar and 130°C in a water-cooled tube bundle reactor. The reactor product with an outlet temperature of 165°C has a mass flow of 78.7 t / h with a composition of 30 wt.% methacrolein and 63.5 wt.% H2O. The reactor product also has a DMA content of 3.5 wt.% and traces of formalin, propionaldehyde, methanol and trimethylamine. The stream is then expanded to ambient pressure and cooled to 83 °C.The liquid and gaseous phases are separated in a flashbox, with the liquid phase being purified in a distillation column by withdrawing gaseous methacrolein and water at the top of the column (at 93°C) and cooling and condensing them together with the gas phase of the flashbox. After decantation, the finished methacrolein product is withdrawn at a rate of 24.3 t / h and has a temperature of 20°C with a composition of 96 wt.% MAL, 1.6 wt.% H2O, and traces of propionaldehyde, methanol, and formaldehyde. The bottom stream of the column has a temperature of 101°C and a composition of 91 wt.% H2O, 5 wt.% DMA, 1 wt.% formalin, traces of methanol, formic and acetic acid, propionaldehyde, and 2 wt.% of other high-boiling-point hydrocarbons.This bottom product is recycled at 37.6 t / h together with fresh reactant and catalyst in the tube bundle reactor, the other part at 16.8 t / h is fed into the thermal afterburner (process step 5) and the organic portion is burned there together with air and natural gas.

[0204] The operating procedure of the MAL synthesis with the conversions of propionaldehyde and formalin, as well as the selectivity to methacrolein, can be found in patent US 9,994,507 B2. The results show the following specific consumption factors for the production of one ton of methacrolein with regard to formaldehyde and propional, as well as the energy used: 0.855 tons% PA / ton of MAL, 0.44 tons% formaldehyde (used as a 55 wt% aqueous formalin solution), 16 kg DMA / ton of methacrolein, 18 kg acetic acid / ton of methacrolein, 1.35 tons steam / ton of methacrolein, as well as 35 kWh of electricity and 90 m 3Cooling water. 0.7 tons of wastewater per ton of methacrolein results as an aqueous ammonium-containing, acetate-acid solution, which also contains high-boiling organic byproducts of the reaction.

[0205] Process step 4: Direct oxidative esterification (part of step f2))

[0206] The methacrolein obtained in process step 3 is first dewatered in a distillation column, the methacrolein recovery column, with the aid of the DOE reactor product, whereby the methacrolein-methanol azeotrope was utilized.

[0207] At the top of the methacrolein recovery column, a distillation product with a composition of 51 wt.% MeOH, 39 wt.% MAL, 6 wt.% MMA, and 4 wt.% low boilers is obtained at 60 °C. This top product is fed to the DOE reactor at a mass flow rate of 86.8 t / h, where the MAL is directly oxidatively esterified to MMA using MeOH and atmospheric oxygen. This reaction is carried out over a gold-containing solid catalyst in the liquid phase at 80 °C and 5 bar, with a partial conversion of 70% of MAL being targeted. For this purpose, air is also fed into the reactor, and this flow is regulated so that the residual oxygen content in the exhaust gas is 4 vol.%.

[0208] In the bottom of the methacrolein recovery column, a bottom product is obtained at 72°C, which contains 61% MMA, 20% MeOH, 14% water and 5% secondary components.

[0209] The bottom product stream amounts to 54.6 t / h and is first mixed with water to extractively separate MMA from water and MeOH. The resulting crude MMA is freed from low-boiling and high-boiling secondary components by distillation, yielding an MMA product with a purity of > 99.99 wt.% at a rate of 31.25 t / h.

[0210] The phase obtained in the extraction process, consisting of water, MeOH, and dissolved MMA, as well as small amounts of secondary components, is fed into the MeOH recovery column for organic recycling. Process wastewater is collected at the bottom of the column and sent for disposal. A distillate product consisting of 88% MeOH, 10% MMA, and 2% secondary components, such as MAL and water, is obtained at the top of the column. Fresh MeOH is also fed into the DOE process at this point to compensate for consumed MeOH. Process additives, such as NaOH, are also added shortly before entering the reactor. The total MeOH recycle flow is 46.8 t / h.

[0211] Based on the mass balance of the DOE reactor, the reaction product discharge is 116 t / h with a composition of 45% MeOH, 37% MMA, 8% MAL, 8% water, and 2% by-products. The second discharge path from the reactor is a reactor exhaust gas of 17,700 Nm³. 3 / h, which contains 95% N2, 4% O2, and 1% organic matter, after being cooled to -23 °C to condense most of the organic matter. This exhaust gas is thermally utilized in process step 5.

[0212] For a better understanding of the explanation, it should be mentioned that the catalyst used in the DOE corresponds to the catalyst from Example 1 in the document WO2023 / 025676.

[0213] The reactor operation, with the conversion of methacrolein and the MMA selectivity, as well as the workup of the reaction product to pure MMA as a sales product corresponds to the description in Example 3 in US 2022 / 0363625 A1 .

[0214] According to the above-described design, the following specific consumption factors are determined for the production of one ton of methyl methacrylate with respect to the methacrolein and methanol used as starting materials, as well as the energy used for this purpose: 0.744 tons% methacrolein / ton MMA, 0.33 tons% methanol (used in IMPCA quality), 16 kg DMA / ton methacrolein. 6 mol% of by-products are produced with respect to the mole of methacrolein used. The relevant by-products are 2.5 mol% methacrylic acid, dimeric methacrolein, and direct oxidative esterification products derived therefrom, totaling approximately 1 mol%, as well as 2 mol% methyl hydroxyisobutyrate and 0.5 mol% of downstream products derived from these by-products. Steam and electricity consumption are calculated from the simulation of the recirculation process according to the specifications and results of US 2022 / 0363625 A1.

[0215] Process step 5: Thermal afterburner (thermal oxidiser) and steam generator

[0216] All organic waste and off-gas streams from process steps 1 to 4 are collected and combusted together with a natural gas stream at 2.1 t / h and 85.8 t / h of air. The natural gas stream is required to increase the calorific value of the waste streams to at least 2.72 MJ / kg, as these streams contain a high inert and water ballast. Combustion of all off-gas and waste streams, including natural gas, produces a total of 16 t / h of CO2. The steam demand for process steps 1-4, totaling 150 t / h, is covered by an additional natural gas-fired steam generator (150 t / h). The CO2 emissions from the steam generator amount to 23.4 t / h with a natural gas input of 8.6 t / h.

[0217] Comparison example V1.1

[0218] By integrating a steam generator into the overall MMA plant infrastructure, the required steam production can be significantly reduced. In this example, the

[0219] Heat recovery through steam generation in the thermal afterburner reduces CO2 emissions from MMA production.

[0220] The process steps 1-4 for the production of the MMA are analogous to the comparison example V1.

[0221] Process Step 5: Thermal Oxidizer Including Steam Generation. In addition to the combustion of organic waste gases and waste described in Comparative Example V1, the combustion heat is used to generate steam. This produces 65 t / h of low-pressure steam at 3.5 bar gauge pressure. Likewise, in formalin production (process step 2), the reaction heat is used to generate steam. 12.2 t / h of steam are extracted from the steam-cooled oxidation reactor. Further heat recovery through the internal use of steam condensate as boiler feedwater achieves a further steam savings of 11.8 t / h.

[0222] All these measures result in a reduction in steam production from the natural gas-fired steam boiler from 150 t / h to 60 t / h, thus reducing CO2 emissions from 23 t / h to 9.2 t / h. The natural gas demand for steam generation also decreases from 8.6 t / h to 3.5 t / h.

[0223] The natural gas has an energy content based on the lower calorific value of 12 kWh / kg.

[0224] Example E1.2

[0225] MMA production based on and methanol from CO2 -Hydrogen

[0226] Process step 6: CO2

[0227] From process steps 1 to 4, the waste and exhaust gas streams are collected and combusted in the thermal afterburner, as in comparative example V1.1. Together with the steam generator, a superstoichiometric combustion of air produces an exhaust gas stream with 141,000 Nm 3 / h and a molar composition of 67.9% N2, 18.9% H2O, 9.4% CO2 and 3.8% O2.

[0228] As described in the state-of-the-art processes for CO2 capture (Compendium of Carbon Capture Technology; DOE / NETL; April 2018), the still-hot exhaust gas at 175°C is first cooled to 40°C with water in a quench column. It is then fed into an absorber column and scrubbed with an aqueous amine solution based on diethanolamine (DEA). Through chemisorption, the CO2 selectively dissolves together with the amine and is discharged at the bottom of the column. The separation efficiency (ratio of absorbed CO2 to CO2 in the exhaust stream) is 90%. A CO2-depleted exhaust gas with 55,176 Nm3 passes overhead. 3 / h and a molar composition of 87.3% N2, 5.4% H2O, 4.9% O2, and 2.4% CO2. The CO2 dissolved together with the amine is passed through a heat exchanger into the desorption column, where it is desorbed from the amine at 120°C. The regenerated amine leaves the column at the bottom and is returned to the absorption column via the heat exchanger. After cooling the overhead product and returning the liquid phase to the top of the column, a concentrated CO2 stream with a capacity of 23.4 t / h and a purity of 99% (dry) at a pressure of 2.4 bar (absolute) is obtained.

[0229] Process step 7: Water electrolyzer (step a))

[0230] In a PEM (proton exchange membrane) electrolysis unit, hydrogen with a purity of 99.99 vol.% is produced at a rate of 4.6 t / h using 41.42 t / h of demineralized (DE) water. The hydrogen pressure is 30 bar. This produces 36.9 t / h of oxygen, which is expelled from the electrolyzer using air as an entraining agent. The required electrical power is 258 MWh / h and is provided by renewable energy sources such as wind, solar, or biomass.

[0231] Process step 8: Methanol synthesis (CO2 to MeOH) (step e))

[0232] The hydrogen produced in process step 7 is compressed to 90 bar using a two-stage compressor. The CO2 obtained from process step 6 is mixed with additional, dry CO2 (imported CO2), with the additional CO2 having a mass flow of 10.4 t / h, and is also compressed to a pressure of 90 bar using a five-stage compression process with intercooling. The additional CO2 comes from an industrial waste gas from fossil carbon sources and has a purity similar to that from process step 6. The two gas streams are fed into a methanol synthesis plant. After mixing the two gas streams, a synthesis gas of 38.4 t / h at 90 bar is obtained with the following molar composition: 72.1% H2, 24.3% CO2, and 3.6% H2O.This is then converted to crude methanol in the methanol synthesis unit, which has a recycle gas compressor, at a temperature of 250°C over a copper / zinc / aluminum oxide catalyst (type Megamax 800 from Clariant). After the stabilization column, in which the dissolved gases, primarily CO2 and dimethyl ether, are separated overhead, crude methanol is obtained with a composition of 64 wt% MeOH, 36 wt% H2O. Other by-products include 700 wt ppm EtOH. The total mass flow is 36.6 t / h. After distillative purification and separation of H2O and liquid by-products, a methanol product with an IMPCA-specific quality and a mass flow of 23.4 t / h is obtained. The exhaust gases from this process are then fed into the thermal afterburner, generating an additional 1.7 t / h of CG2 emissions. These are then fed into process step 6 and further processed accordingly.This reduces imported CO2 by 1.53 t / h.

[0233] The methanol produced is fed to process steps 2 and 4 and the MMA is produced analogously to example V1.

[0234] Example E1.3

[0235] MMA production based on ethylene, sulfur and methanol produced from imported and captured CO2 from a Direct Air Capturina (DAC) plant and electrolysis hydrogen

[0236] The example was carried out analogously to Example E1.2, with the exception that the imported CO2 is not extracted from industrial waste gases from fossil sources, but is captured directly from the air or derived from biogenic carbon sources. The process is based on technology from Climeworks. Assuming that electricity demand and process heat are also covered by renewable energy, the resulting CO2 has a negative footprint. This allows the indirect (Scope 3) CO2 emissions from the raw materials for MMA synthesis to be reduced by a further 8.9 t / h.

[0237] Patent example E1.4

[0238] MMA production based on ethylene, sulfur and methanol produced from captured and imported CO2 from a Direct Air Capturing (DAC) plant and electrolysis hydrogen and oxygen

[0239] The example was carried out analogously to example E1.3, with the addition that the dry oxygen obtained from the water electrolyzer (process step 7) is partially fed into the air supply of process step 4 (MMA ex MAL via DOE) and / or is at least partially utilized in the thermal afterburner of process step 5. This makes it possible to reduce the volume flow of air supply in both process steps, whereby the electrical power of the compressors and blowers can be reduced by 2.7 MW (32%). In addition, the inert gas ballast of the DOE exhaust gas in the thermal afterburner is reduced, leading to a reduction of 1.25 t / h of natural gas.

[0240] Example E1.5 MMA production based on and methanol out of

[0241] -hydrogen and oxygen and from bioethanol

[0242] The example was carried out analogously to Example E1.3, with the addition that ethylene is produced from bioethanol (based on corn). Due to the plant's absorption of CO2 from the atmosphere, the indirect CO2 equivalent emissions (cradle-to-gate) of the resulting bioethanol are considered negative. In this example, a value of -0.7 kgCO2 eq / kg ethanol is assumed, which corresponds to a typical value for bioethanol based on corn (see: Life-Cycle Greenhouse Gas Emission Reductions of Ethanol with the GREET Model (https: / / afdc.energy.gov / files / u / publicati0n / ethan0l-ghg-reducti0n-with-greet.pdf, last accessed on July 18, 2023).

[0243] Process step 12: Ethanol to

[0244] According to the publication in ChemBioEng Review 2017, 4, No. 2, 75-91, 18.6 t / h of bioethanol are converted into (bio)ethylene in a dehydration process. The ethanol is first heated to 425°C at 5 bar, evaporated, and then fed into a four-stage reactor section with intermediate heaters. The required heat is supplied via electric heaters, with the electricity generated, as before, from renewable sources. The reactors are operated under adiabatic conditions and are equipped with a SynDol catalyst, which consists of the main components aluminum, manganese, and silicon dioxide. The reactor product also corresponds to 18.6 t / h of bioethanol feed and contains 56.11 wt% ethylene, 41.3 wt% water, as well as 980 ppm (mass) CO2 and 0.75 wt% other components (acetaldehyde and diethyl ether).

[0245] After cooling and water quenching, the reactor product stream is then compressed in several stages to 27 bar and fed into a NaOH scrubber, which helps reduce the CO2 concentration to below 5 ppm. This is followed by cooling to 15°C and drying using molecular sieves. The resulting high-pressure ethylene stream has a purity of 99.2 wt.% and a mass flow of 10.5 t / h.

[0246] To achieve a purity of 99.97 wt.% (polymer grade), the high-pressure ethylene stream is freed from the low- and higher-boiling components in a final step. The ethylene stream is first cooled to -25.7°C by depressurization to 22 bar and then passed into a first high-boiling column. In this column, the high-boiling components are removed at the bottom at -16°C at a mass flow rate of 0.19 t / h and a composition of 34.8 wt.% (balance: ethylene). The overhead product, together with the overhead product from the stripper column described below, is further cooled to -40°C to condense out the ethylene, and the volatile components are subsequently separated off. This condensed stream has a mass flow rate of 0.15 t / h and contains 93.5 wt.% ethylene and 6.5 wt.% low-boiling components. The condensed stream is fed back to the stripper column (low boiler column) at the top and then withdrawn at the bottom.After heat exchange with the high-pressure ethylene stream, the ethylene product is obtained at 10°C and 22 bar with a mass flow of 10.15 t / h. All waste and exhaust gas streams from this process step are fed into the thermal afterburner (process step 5) and combusted there. An additional 1.84 t / h of CO2 is produced there.

[0247] Patent example E1.6

[0248] MMA production based on ethylene, synthesis gas and methanol produced from captured and imported CO2 from a Direct Air Capturing (DAC) plant, electrolysis hydrogen and oxygen and ethylene from ethanol produced from CO2 and Hz

[0249] The example was carried out analogously to Example E1.5 with the change that ethanol is produced from CO2 and H2 via a water gas conversion reaction (RWGS) followed by a gas fermentation process.

[0250] Process step 13: Water gas conversion reaction - enql. Reverse Water Gas Shift (RWGS) In this process step, 5.74 t / h of H2 from the water electrolyzer (process step 7) together with 44.9 t / h of additional CO2 (from a DAC or of biogenic origin) are provided as the reactant gas stream. The RWGS is based on the example from DE 102017 120 814 A1 or WO 2023 / 056218 and consists of a fixed-bed reactor equipped with a Ni-containing catalyst. The reaction takes place at temperatures in the range of 800 °C - 900 °C. In addition, water (45 wt. %) is added to the reactant gas stream to prevent possible coking in the reactor. Furthermore, the by-product yield of methane is very low under these conditions. At typical pressure conditions of 30 bar and the temperatures described, a CO2 conversion of 40% is achieved. The resulting reactor product has a composition of 16 vol.% CO2, 16 vol.% CO, 27 vol.% H2, and 37.8 vol.% H2O and residual N2 or CH4 are dried by cooling, and a synthesis gas consisting of 25.9 t / h of CO and 3.7 t / h of H2 is separated. Unconverted CO2 is recycled to the fixed-bed reactor via a recycle gas compressor.

[0251] Process step 14: Gas fermentation to ethanol

[0252] In this process step, the syngas from process step 13 is used to produce ethanol by gas fermentation based on acetogenic microorganisms that produce ethanol via anaerobic respiration and carbon fixation (via the Wood-Ljungdahl pathway). The bacterial strain Clostridium ljungdahlii used for this purpose is described in WO 2007 / 117157. The gas fermentation process is disclosed in the article "Production of ethanol fuel via syngas fermentation: Optimization of economic performance and energy efficiency" - https: / / doi.org / 10.1016 / j.cesx.2020.100056. Syngas is introduced into a bioreactor at 37°C together with the fresh bacterial strain and water. With a productivity of 4.5 g / l / h, ethanol is obtained with a conversion of 93% and a selectivity to ethanol of 94%. The secondary yield of acetic acid based on CO is 0.42%. In a purification section, the (diluted) reactor product with an ethanol content of 1-4 wt.% in a so-called beer column. Here, water and CO2 are removed, while concentrated (40 wt.%) ethanol is withdrawn as a side stream and passed into a rectification column for further concentration (92.5 wt.%). This distillate is further withdrawn as saturated vapor and superheated before being passed on for dehydration with molecular sieves. The resulting ethanol product, at 18.6 t / h, has an ethanol content of (99.5 wt.%). The CO2 and off-gas streams from the beer column are subsequently processed in a waste gas scrubber to recover ethanol. The resulting liquid bottom products from the beer and rectification columns are mixed together and partially fed back into the bioreactor as a recycle stream. The remainder is discharged as wastewater.

[0253] The ethanol product is then fed to process step 12 and processed into MMA analogously to example E1.5.

[0254] The total hydrogen demand from the water electrolyzer (process step 7) for the MMA plant amounts to 10.3 t / h, which corresponds to an electrical power consumption of 580 MW. By assuming CO2-free (renewably generated) electrical energy, no (indirect) CG2 emissions are included in the CO2 footprint analysis.

[0255] The total CO2 demand for process steps 8 and 13 amounts to 78.7 t / h, of which 23.5 t / h comes from the carbon capturing plant (process step 6). Thus, 55.2 t / h of CO2 are imported. Assuming that this imported CO2 is of biogenic origin (biogas plant, etc.) or from a direct air capturing plant (see example E1.3), it is assumed that the imported CO2 has a negative footprint of -1 kgCO2aq / kgCO2.

[0256] Results overview and interpretation

[0257] Table 1: Results of the CO2 intensity of MMA production - given in emissions per hour and specifically per ton of MMA.

[0258] Table 1 clearly shows that the improved heat integration of thermal oxidizers (steam generation) already enables a specific CO2 reduction of just under 20%. If this option is further supplemented by a carbon capture unit with subsequent methanol synthesis (E1.2) and a direct air capture system (E1.3), even greater reductions in the product carbon footprint are possible. These savings amount to 65% and 75%, respectively, based on the original value of 3.14 kg CO2,aq / kg MMA. The integration of oxygen from water electrolysis results in an additional saving of 0.2 CO2,aq / kg MMA. By using bioethanol as the feedstock for ethylene production, the PCF of the MMA becomes negative, and overall, more CO2 (equivalent) is absorbed from the environment than emitted. This effect can be further increased if the ethanol is produced using CO2 from a direct air capture system and green H2.

[0259] This is particularly achieved through the use of renewable energy, especially for operating the water electrolyzer and other electrical consumers. Comparative example V2:

[0260] MMA production based on

[0261] Natural gas with a mass flow of 5.8 t / h is mixed with oxygen (10.29 t / h) and saturated steam (250°C, 40 bar and a mass flow of 9 t / h) with the typical gasification ratios of steam to carbon of 1.4 (mol / mol) and oxygen to carbon of 1.6 (mol / mol) at 400°C and 25 bar. Together with an additional, internal CO2 cycle stream, this stream with a composition of 37 vol.% H2O, 24 vol.% O2, 25 vol.% CH4 and 13.3 vol.% CO2 as well as residues of C2 and C3 hydrocarbons from the natural gas is fed into a reactor for partial oxidation and converted into a synthesis gas at 1400°C and 25 bar. After subsequent cooling to 40 °C, during which most of the process-related water is separated, a dry synthesis gas with a composition of 44 vol.% H2, 37 vol.% CO, 18 vol.% CO2, and residues of H2O is obtained.This dry synthesis gas is then fed into a CO2 absorption system based on an aqueous monoethanolamine solution. After desorption at 120°C and ambient pressure, the CO2 (with a mass flow of 7.95 t / h and a purity of 99 vol%) is compressed to reactor inlet level (25 bar) using a compressor and returned to the reactor along with the inlet streams.

[0262] In order to produce a synthesis gas with an H2:CO ratio of 1:1, the CO2-purified synthesis gas with a mass flow of 11.45 t / h and a composition of 53 vol.% H2, 45 vol.% CO, as well as residues of H2O and CO2, is fed into a membrane unit at 40°C and 20 bar. There, a portion of the hydrogen is separated from the synthesis gas with a selectivity of 17%. This produces a synthesis gas stream with an H2:CO ratio of 1:1 and a mass flow of 11.3 t / h, which serves as the starting material for propionaldehyde synthesis. The permeate stream with a composition of 95 vol.% H2 and 5 vol.% CO at 100 mbar overpressure is then thermally utilized. This results in 0.16 t / h of CO2 emissions.

[0263] Process step 9: Production of synthesis gas H2:CO 2:1 via POX from natural gas including water gas shift

[0264] Synthesis gas with an H2:CO ratio of 2:1 based on partial oxidation of natural gas: Natural gas with a mass flow of 33.6 t / h is mixed with oxygen (55.2 t / h) and saturated steam (250°C, 40 bar and a mass flow of 51.2 t / h) with the typical gasification ratios of steam to carbon of 1.4 (mol / mol) and oxygen to carbon of 1.6 (mol / mol) at 400°C and 25 bar. Together with an additional CO2 cycle stream, this stream with a composition of 39 vol.% H2O, 24 vol.% O2, 26 vol.% CH4 and 8.5 vol.% CO2 as well as residues of C2 and C3 hydrocarbons from the natural gas is fed into the reactor for partial oxidation and converted into a synthesis gas at 1400°C and 25 bar. 21% of this synthesis gas is passed over a copper-containing catalyst in an isothermal water gas shift (WGS) reactor at 250°C and 20 bar.With a GHSV of 6000 per hour, the gas reacts to its thermodynamic equilibrium at 250°C and 20 bar. Following subsequent cooling and drying at 40°C, a raw synthesis gas is obtained with a composition of 63 vol% H2, 35 vol% CO2, and residues of CO, H2O, and methanol. The CO2 is then removed to 99% using a pressure swing adsorption (PSA) system. The hydrogen stream, with a purity of 99.99 vol% and a mass flow of 2.1 t / h, is then mixed with the raw synthesis gas, which has previously been cooled, dried, and purified of CO2 in a monoethanolamine absorption scrubber (see process step 8). The synthesis gas thus obtained with a composition of H2:CO 2:1, as well as residues of H2O, MeOH and CO2 and a mass flow of 50.2 t / h is then used for the production of methanol and ethanol.The CO2 stream separated from the PSA has a mass flow of 26.1 t / h and contains traces of H2. It is subsequently combusted in process step 5.

[0265] Process step 10: Methanol synthesis

[0266] For methanol synthesis, synthesis gas with a H2:CO molar ratio of 2:1 from process step 9 of the previous partial oxidation of natural gas with a mass flow of 24.6 t / h is used. This synthesis gas is pressurized to 80 bar using a two-stage compressor and fed, together with a recycle gas, into a steam-cooled methanol reactor with a copper-containing catalyst (Clariant MegaMax 800). The outlet gas has a temperature of 250°C and is subsequently cooled to 40°C. The liquid reaction products (MeOH and H2O) are separated from the outlet gas, and the remaining gaseous reactants are subsequently recycled using a recycle compressor (2 bar pressure difference). The reflux ratio between fresh gas and recycle gas is 2.2 (mol / mol). To prevent the accumulation of inert components, a part (9.36 t / h with H2 61 vol.% and 29 vol.-% CO) is separated and utilized in a thermal afterburner (process step 5). The total conversion based on the CO used is 95%.

[0267] The liquid reaction product contains 90 wt.% MeOH, 5 wt.% H2O, and dissolved gases (mainly CO2). It is then boiled in a fore-ends column to remove CO2. The resulting stabilized crude methanol is then rectified in a 40-tray product column at ambient pressure, and H2O is separated. The methanol product, at 23.4 t / h, has a purity of 99.8 wt.%, with the minor components being H2O and ethanol. Process step 11: Ethanol via synthesis

[0268] For the production of ethanol from synthesis gas, reference is made to the process described in US 2009 / 0221725 A1. Synthesis gas with an H2:CO molar ratio of 2:1 from process step 9 is used at a total mass flow of 28.3 t / h. In this process, 14.3 t / h of synthesis gas are converted to methanol with a mass flow of 13.6 t / h according to the methanol synthesis described above (process step 10). The remaining portion of the synthesis gas is first passed through a gas membrane consisting of a polyamide composite structure with polyimide support as described in Sustainability 2019, 11, 703. Under the conditions disclosed in US 2009 / 0221725 A1, a retentate stream with a CO purity of 97% and a mass flow of 12.0 t / h is achieved through a 3-stage system. On the permeate side, a CO-depleted stream with a composition of 98 vol.% H2 and 1.5 vol.% CO with a mass flow of 2.06 t / h is obtained.

[0269] The CO2-rich retentate stream is then converted in a carbonylation step together with the methanol from process step 10 (13.6 t / h) and a recycle methanol stream (12.9 t / h) at 250°C and 50 bar pressure over a Rh / Ir catalyst system in a fixed-bed reactor with a GHSV of 10,000 per hour. According to US 2009 / 0221725 A1, 50 wt.% acetic acid and 50 wt.% methyl acetate are produced there. The CO2 conversion is almost 100%. The resulting mixture is then passed through another reactor filled with aluminum zeolites at 150°C and 1 bar pressure. There, the remaining methanol is completely converted with the acetic acid to form methyl acetate (methyl acetate). After cooling, a mass flow of 39.2 t / h is obtained with a composition of 80 wt% methyl acetate and 20 wt% H2O with traces of MeOH.

[0270] After the water is removed by distillation, the methyl acetate is completely evaporated at 200°C and 50 bar pressure. It is mixed with 2.07 t / h of H2-rich permeate stream and passed over a Cu / Zn / Al catalyst. There, the hydrogenation reaction of methyl acetate and H2 produces a product mixture of 58 wt.% ethanol and 41 wt.% MeOH with a conversion of 95% based on methyl acetate. After cooling to 40°C, unreacted gaseous components (mainly CO) are separated and fed into the thermal afterburner.

[0271] In the subsequent distillative purification, the methanol and unreacted methyl acetate (mass flow 14.5 t / h and a composition of 89.1 wt% MeOH and 10.9 wt% ethanol) are withdrawn at 1 bar and 65°C via the top of the column and fed back into the carbonylation step.

[0272] At the end, an ethanol product stream is withdrawn from the bottom of the column at 78°C with a mass flow rate of 18.6 t / h and a purity of 99.5 wt.%. The conversion of ethanol to ethylene proceeds analogously to process step 12 of Example E 1 .5.

[0273] The MMA production is carried out analogously to comparative example V1 with the process steps 1 to 4 described therein and the respective waste streams are thermally converted to CO2 according to process step 5.

[0274] Process step 5: Thermal afterburner (thermal oxidiser) and steam generator

[0275] All organic waste and off-gas streams from process steps 1 to 9 are collected and combusted at a superstoichiometric rate (5%) with a natural gas stream of 2.1 t / h and 85.8 t / h of air. Since some of the waste streams contain high levels of water and inert ballast, natural gas is required as a supporting fuel to raise the calorific value of the waste stream to a suitable combustion level of 2.7 MJ / kg. The resulting heat is used for steam production, which primarily meets the steam requirements of process step 4 (requires 150 t / h) and all other process steps (8-12). Combustion produces a total of 50.6 t / h of CO2.

[0276] Additional steam demand (60 t / h) is provided by a separate steam generator, with the combustion of 3.4 t / h of natural gas resulting in additional 9.4 t / h of CO2 emissions.

[0277] Example E2.1 in a plasma reformer and

[0278] The process steps are analogous to comparative example V2 (process steps 1, 2, 3, 4, 5, 8, 9, 10, 11). Additionally, a carbon capture unit (CCU) is installed downstream of the thermal afterburner and the steam generator. The resulting CO2 is then fed to a plasma reforming reactor, where it is converted into synthesis gas, which is then fed into the respective process steps 1, 10, and 11.

[0279] The process steps in detail:

[0280] Process step 6: CO2

[0281] As in comparative example V2, the waste and exhaust gas streams from process steps 1 to 12 are collected and combusted in the thermal afterburner. Combined with the steam generator, a superstoichiometric combustion of air produces an exhaust gas with a volume of 198,400 Nm 3 / h and a molar composition of 67.9% N2, 18.9% H2O, 9.4% CO2, and 3.8% O2. In addition, a CC>2 recycle stream from process steps 13 and 14 with 4.5 t / h of CO2 is fed into the carbon capture unit.

[0282] As described in the state-of-the-art processes for CO2 capture (Compendium of Carbon Capture Technology; DOE / NETL; April 2018), the still-hot exhaust gas at 175°C is first cooled to 40°C in a quench column with water. It is then fed into an absorber column and scrubbed with an amine solution based on diethanolamine (DEA). Through chemisorption, the CO2 and the amine are selectively dissolved and discharged at the bottom of the column. The separation efficiency is 87%. A CO2-depleted exhaust gas with 112,000 Nm³ passes overhead. 3 / h and a molar composition of 87.3% N2, 5.4% H2O, 4.9% O2 and 2.4% CO2.

[0283] The CO2-enriched amine is fed through a heat exchanger into the desorption column, where it is desorbed from the amine at 120°C. The depleted amine leaves the column at the bottom and is returned to the absorption column via the heat exchanger. After cooling the overhead product and returning the liquid phase to the top of the column, a concentrated CO2 stream of 35.8 t / h with a purity of 99% (dry) is obtained at a pressure of 3.4 bar (absolute).

[0284] Process step 13: Synthesis gas (2:1) production with plasma reformer (incl. WGS)

[0285] A portion of the CO2 captured from process step 6 (29.5 t / h) is fed together with 17 t / h of natural gas and 26.9 t / h of steam into a plasma reformer as described in US 10,906,806 and US 10,906,807 respectively.

[0286] US 10,927,007. This has an electrical output of 110 MW for heating and providing thermal energy for the conversion reaction. At a temperature of 1000°C and 20 bar, a synthesis gas is produced, a portion of which (11%) is additionally converted in a water-gas conversion reactor and, after cooling and drying, is purified of CO2 and CO using a pressure swing adsorption column (PSA). The resulting H2-rich gas is mixed with the remaining dry synthesis gas to produce a synthesis gas at a rate of 53 t / h with a molar H2:CO ratio of 2:1 and 6 vol.% CO2 as well as residues of H2O and CFk. This synthesis gas is fed to process steps 10 and 11 described in Comparative Example 11 in the respective quantities.

[0287] The exhaust gas stream (tail gas) with 66 vol.% CO2 and 33 vol.% CO at 4.36 t / h is returned to process step 6 and thermally utilized there.

[0288] Process step 14: Synthesis gas (1:1) production with plasma reformer

[0289] To produce a synthesis gas with a molar H2:CO ratio of 1:1, analogous to process step 12, concentrated CO2 from process step 11 is fed into a plasma reformer together with 3.6 t / h of natural gas and 3.63 t / h of steam at 1400 °C and 20 bar, where it is converted. With steam preheating to 300 °C, the reactor has an electrical output of 24 MW. The resulting dry synthesis gas, at 11.3 t / h, already has the desired H2:CO ratio with an additional CO2 content of 6 vol.% and residual H2O and methane.

[0290] This is then passed on to process step 1.

[0291] The final MMA production of 31.25 t / h is carried out analogously to comparative example V2 with the corresponding process steps. Example E2.1 shows that the use of the carbon capture unit in conjunction with the plasma reforming technology including CO2 injection significantly reduced direct CO2 emissions (including steam) (~90%). The concentrated CO2 emissions from the CO2 capturing plant are sufficient to provide the required amount of synthesis gas for the raw material production of formaldehyde, propionaldehyde, and methanol for the MMA process. However, the high power consumption of the plasma reformer and its indirect CO2 emissions almost completely offset the savings in direct CO2 emissions. As a result, the PCF decreases by only 2% compared to comparative example V2. Assuming green electrical energy (with a CO2 intensity of assumed 0 kgco2aq / kWh), the example E2.2 show that the PCF can be significantly reduced (80%) compared to the comparative example V2.

[0292] Table 2: Overview of CO2 emissions from comparative example V2 and example E2 and their PCF

Claims

Claims 1. A process for producing a (meth)acrylate comprising the following steps a) to f): a) providing a first stream containing hydrogen starting from water, b) providing a first process gas containing CO2 by thermal conversion of a stream from an industrial process, c) separating the CO2 contained in the first process gas by absorption or adsorption of the CO2 on a medium with subsequent desorption of the CO2 from the medium to obtain a CO2-containing stream, d) mixing the first stream provided in step a) with the CO2-containing stream obtained in step c) to obtain a mixed stream containing the first stream and the CO2-containing stream, e) reacting at least a portion of the mixed stream obtained in step d) to obtain a first process stream comprising at least one compound containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms,f) reacting at least a portion of the first process stream obtained in step e) to obtain the (meth)acrylate, wherein the reaction in step f) comprises the following steps f1) and f2): f1) reacting ethene and / or methanol with a CO-containing stream in the presence of a metal catalyst to obtain an organic compound having at least 2 carbon atoms, wherein at least one of the reacted compounds selected from ethene, methanol, and CO-containing stream is the compound obtained in step e) containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms, or is prepared therefrom, f2) reacting the organic compound obtained in step f1) with formaldehyde to obtain the (meth)acrylate.

2. A process for producing a (meth)acrylate comprising the following steps a) to f): a) providing a first stream containing carbon and hydrogen starting from a hydrocarbon of the general formula Cn H2n+2, where n is an integer in the range from 1 to 10, b) providing a first process gas containing CO2 by thermal conversion of a stream from an industrial process, c) separating the CO2 contained in the first process gas by absorption or adsorption of the CO2 on a medium with subsequent desorption of the CO2 from the medium to obtain a CO2-containing stream, d) mixing the first stream provided in step a) with the CO2-containing stream obtained in step c) to obtain a mixed stream containing the first stream and the CO2-containing stream, e) reacting at least a portion of the mixed stream obtained in step d) to obtain a first process stream comprising at least one compound containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms, f) reacting at least a portion of the first process stream obtained in step e) to obtain the (meth)acrylate, wherein the reaction in step f) comprises the following steps f1) and f2): f1) reacting ethene and / or methanol with a CO-containing stream in the presence of a metal catalyst to obtain an organic compound having at least 2 carbon atoms, wherein at least one of the reacted compounds selected from ethene, methanol and CO-containing stream is the compound obtained in step e) containing 1 to 4 carbon atoms and 1 to 2 oxygen atoms or is prepared therefrom, f2) reacting the organic compound obtained in step f1) with formaldehyde and obtaining the (meth)acrylate.

3. Process according to claim 1, characterized in that the hydrogen contained in the first stream provided in step a) is provided by electrolysis of water and electricity used in the electrolysis originates at least partly from renewable energies and / or non-fossil energy sources, wherein in addition to the first stream an oxygen stream is provided and the oxygen stream provided is used at least partly in at least one process selected from the group consisting of the provision in step b), an aerobic wastewater treatment, a thermal utilization, a direct oxidative esterification and a formaldehyde synthesis.

4. Process according to claim 2, characterized in that the first stream provided in step a) contains carbon and hydrogen starting from a C1 to C4 hydrocarbon, preferably methane, and in step e) the first process stream comprises CO as at least one compound.

5. Process according to one of claims 1 to 4, characterized in that in step f1) the CO-containing stream is reacted with hydrogen and ethylene in a hydroformylation reaction to give propanal as an organic compound having at least 2 carbon atoms and in step f2) the propanal is reacted with formaldehyde to give methacrolein, wherein in a further step methacrolein is reacted in the presence of an oxygen-containing gas to give methacrylic acid and / or methacrylic acid ester.

6. Process according to one of claims 1 to 5, characterized in that the industrial process in step b) is selected from the group consisting of a synthesis gas production, a formic acid production, a methyl formate production Production, an oxosynthesis, a formaldehyde synthesis, a formalin synthesis, a methyl (meth)acrylate synthesis, a power generation and a steam generation.

7. The method according to any one of claims 1 to 6, characterized in that the method additionally comprises the following step b1): b1) providing a third process gas containing CO2 by aerobic wastewater treatment, wherein the CO2 contained in the third process gas is separated following step b1), optionally analogously to step c).

8. The process according to any one of claims 1 to 7, characterized in that the medium in step c) is selected from the group consisting of zeolites, metal-organic frameworks, a basic liquid and a basic solid.

9. A process according to any one of claims 1 to 8, characterized in that the adsorption or absorption in step c) is carried out at a first temperature which is in the range from 0 °C to 50 °C and / or that the desorption in step c) takes place at a second temperature which is in the range from 60 °C to 150 °C.

10. The method according to any one of claims 1 to 9, characterized in that the first process gas is purified after step b) and before step c).

11. Process according to one of claims 1 to 10, characterized in that the volume ratio of the first stream to the CO2-containing stream in step d) is in the range from 1 to 1 to 4 to 1 12. The process according to any one of claims 1 to 11, characterized in that the at least one compound of the first process stream is selected from the group consisting of CO, methanol, ethanol, 1-propanol, isobutanol and tert-butanol.

13. Process according to one of claims 1 to 12, characterized in that the reaction in step e) is carried out fermentatively or in the presence of a catalyst.

14. The process according to any one of claims 1 to 13, characterized in that the first process stream obtained in step e) is purified after step e) and before step f).

15. The process according to any one of claims 1 to 14, characterized in that the at least one compound obtained in step e) comprises ethanol and that in step f1) converted ethene is provided by dehydration of the ethanol obtained in step e).

16. The process according to any one of claims 1 to 15, characterized in that the at least one compound obtained in step e) comprises methanol and is used as methanol in step f1) and / or is converted to formaldehyde and then used in step f2).

17. The process according to any one of claims 1 to 16, characterized in that the at least one compound obtained in step e) comprises CO and is used in step f1) as a CO-containing stream.

18. The process according to any one of claims 1 to 17, characterized in that the organic compound having at least 2 carbon atoms obtained in step f1) is selected from the group consisting of acetic acid, methyl acetate, propanal, propionic acid and methyl propionate.

19. The process according to any one of claims 1 to 18, characterized in that in the reaction in step f2) first (meth)acrolein is formed, which is then further converted to the (meth)acrylate.

20. The process according to any one of claims 1 to 19, characterized in that in the reaction in step f1), methyl propionate is first formed as an organic compound, which is then further converted to the (meth)acrylate in step f2).

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