Synthetic methanol with a low deuterium content derived from non-fossil resources

Abstract

A method for producing methanol having a deuterium content of less than 90 ppm based on the total hydrogen content, (a) supplying hydrogen having a deuterium content of less than 90 ppm based on the total hydrogen content by water electrolysis using electricity generated at least partially from non-fossil renewable resources; and (b) supplying carbon dioxide; and (c) reacting hydrogen and carbon dioxide in the presence of a catalyst to form methanol comprising a method.

Description

Technical Field

[0001] The present invention relates to a method for producing methanol having a deuterium content of less than 90 ppm based on the total hydrogen content, the methanol obtained thereby, and its use.

Background Art

[0002] In the chemical industry, methanol serves as a raw material in the production of olefins, formaldehyde, acetaldehyde, acetic acid, methyl acetate, acetic anhydride and vinyl acetate. Conventional production methods involve a catalytic process using fossil raw materials such as natural gas or coal.

[0003] Synthesis gas (syngas) for producing methanol can be produced from many sources including natural gas, coal, biomass, or virtually any hydrocarbon feedstock, by reaction with steam (steam reforming), carbon dioxide (dry reforming) or oxygen (partial oxidation).

[0004] Syngas is produced, for example, from solid feedstocks via coal gasification. Thereby, coal is reacted with a mixture of partial oxidation with air or pure oxygen and gasification with steam to obtain a mixture of carbon monoxide and hydrogen. Through the Boudouard equilibrium, carbon monoxide is in equilibrium with carbon and carbon dioxide.

Chemical Formula

[0005] Furthermore, the water gas shift reaction has to be taken into account.

Chemical Formula

[0006] The exothermic reaction with oxygen provides the energy necessary to achieve the high reaction temperature for the endothermic gasification reaction of carbon with steam.

[0007] As a rule, in addition to coal, other solid raw materials (wood, straw) can be used instead.

[0008] The most important gaseous extract for producing syngas is natural gas, which is reacted with steam via steam reforming. Natural gas provides the highest hydrogen-to-carbon monoxide ratio.

Chem.

[0009] Also, liquid extracts such as light naphtha cuts can be reacted with steam via steam reforming after sulfur removal.

[0010] To produce methanol, the ratio of carbon monoxide to hydrogen in the syngas is adjusted to satisfy the reaction equation.

Chem.

[0011] Syngas is mainly produced via steam reforming or partial oxidation of natural gas or via coal gasification. Natural gas is used for methanol production in North America and Europe, while in China and South Africa, syngas production is mainly coal-based. Depending on the ratio of carbon monoxide to hydrogen, the product gas is named water gas (CO + H2), syngas (CO + 2H2) or spaltgas (CO + 3H2). Spaltgas can be depleted in hydrogen or concentrated in carbon monoxide via the water gas shift reaction, for example by adding carbon dioxide and removing water, and water gas can be concentrated in hydrogen or depleted in carbon monoxide to obtain syngas.

[0012] The synthesis of methanol from CO2 is less exothermic than starting from syngas and also involves the reverse water gas shift (RWGS) as a secondary reaction. To promote methanol synthesis, the CO in the syngas is converted to CO2 through the water gas shift (WGS) reaction. CO2 + 3H2 → CH3OH + H2O ΔH298K = -49.5 kJ mol-1 CO2 + H2 → CO + H2O ΔH298K = 41.2 kJ mol-1

[0013] When CO2 is derived from a suitable direct or indirect biological origin, the above water-gas equilibrium provides the basis for producing CO2-neutral methanol. According to the reverse water-gas shift (RWGS) reaction, there is an opportunity to include biogenic CO2 directly in the syngas-methanol process. Then, using a CuO / ZnO / Al2O3 catalyst, syngas is converted to methanol, for example, in the temperature range of 250 - 300 °C and pressure range of 5 - 10 MPa.

[0014] In that sense, different biogenic carbon sources in the form of CO2 could be included in syngas to form methanol. The biogenic source of CO2 could be from the fermentation process of biomass materials, the combustion process of biomass, or the waste of bio-based materials, or could form, for example, an extraction and regeneration process step, such as the extraction process of atmospheric CO2 by amine CO2 scrubbing.

[0015] Of course, it would also be possible to mix a mixture of CO2 from biogenic carbon sources and fossil carbon sources to produce methanol.

[0016] 12 The natural abundance of 12C is about 98.9%, 13 and the natural abundance of 13C is about 1.1%. The 13 13C / 12 12C isotope ratio of a chemical compound is given in comparison to the Vienna-Pee-Dee-Belemnite-Standard (V-PDB), which is an international standard. 13 13C / 12 12C isotope ratio is given as a δ 13 13C value in units of ‰. By definition, the standard has a δ 13 13C value of 0‰. Substances with a higher 13 13C content than the standard have positive ‰ values, and substances with a lower 13The substance having a C content has a negative ‰ value.

[0017] In physical organic chemistry, the kinetic isotope effect is the change in the reaction rate of a chemical reaction when one of the atoms in the reactant is replaced by one of its isotopes. Formally, this is the ratio of the rate constants k L (for the lighter) and k H (for the heavier) isotopically substituted reactants (isotopologues) of the reaction, k L / k H . This change in reaction rate is mainly a quantum mechanical effect arising from the heavier isotopologues having lower vibrational frequencies compared to their lighter counterparts. In most cases, this means that the heavier isotopologues require a greater energy input to reach the transition state and, as a result, have a slower reaction rate.

[0018] Isotope rate changes are most pronounced when the relative mass change is greatest because the effect is related to the vibrational frequency of the bond being affected. For example, changing a hydrogen atom (H) to its isotope deuterium (D) represents a 100% increase in mass, 12 but changing 13 C to 12 C only increases the mass by 8 percent. The rate of reactions involving C-H bonds is typically 6 - 10 times faster than the corresponding C-D bonds, 13 but

[0019] C reactions are only 4 percent faster than the corresponding 13 C reactions.

Summary of the Invention

Problems to be Solved by the Invention

[0020] The object of the present invention is to provide an environmentally friendly method for producing methanol. A further object of the present invention is to provide methanol having a low deuterium content. The favorable kinetic isotope effect caused by the low deuterium content of methanol can be cumulative because it also exists in subsequent production steps further downstream in the value chain.

Means for Solving the Problems

[0021] This object is achieved by a method for producing methanol having a deuterium content of less than 90 ppm based on the total hydrogen content, (a) supplying hydrogen having a deuterium content of less than 90 ppm by water electrolysis using electricity generated at least partially from non-fossil renewable resources; and (b) supplying carbon dioxide; and (c) reacting hydrogen and carbon dioxide in the presence of a catalyst to form methanol including.

[0022] Fossil-based methanol from syngas generally has a δ 13 C value in the range of -50‰ to -25‰ depending on the fossil raw material. Methanol based on carbon dioxide captured from ambient air generally has a δ 13 C value corresponding to the δ 13 C value in the range of -10‰ to -2.5‰.

[0023] In a preferred embodiment of the method of the present invention, the carbon dioxide supplied in step (b) has a δ 13 C value greater than -20‰ 13 C content. In particular, the carbon dioxide supplied in step (b) has a δ 13 C value corresponding to -10‰ to -2.5‰ 13 C content.

[0024] Therefore, when carbon dioxide is captured from ambient air, the 13 C content of methanol generally has a δ greater than -20‰13 corresponding to the C value, and more specifically δ of -10 to -2.5‰ 13 corresponds to the C value.

[0025] The present invention also relates to methanol having a deuterium content of less than 90 ppm based on the total hydrogen content. Preferably, the deuterium content is 30 to 75 ppm based on the total hydrogen content.

[0026] The deuterium content of hydrogen and chemical compounds containing hydrogen is, in this specification, expressed in atomic ppm based on the total hydrogen content (total atoms of protium 1 H and deuterium 2 H).

[0027] Ethylene can be prepared using methanol having a deuterium content of less than 90 ppm, preferably 30 to 75 ppm, based on the total hydrogen content. Generally, the ethylene obtained also has a low deuterium content of less than 90 ppm, preferably 30 to 75 ppm. When carbon dioxide is captured from the ambient air, the 13 C content of the ethylene obtained also generally corresponds to a δ 13 value greater than -20‰, and more specifically a δ 13 value corresponding to -10 to -2.5‰.

[0028] Electrolysis of water is an environmentally friendly method for producing hydrogen because it uses renewable H2O and produces only pure oxygen as a by-product. Furthermore, water electrolysis utilizes sustainable energy resources such as sunlight, wind power, hydropower, and direct current (DC) from biomass.

[0029] By electrolysis of water, it is observed that the deuterium atom content of hydrogen is lower than that of petrochemically produced hydrogen, such as that contained in synthesis gas, and is generally less than 90 ppm, preferably 30 to 75 ppm. The deuterium atom content in hydrogen produced by electrolysis can be as low as 15 ppm. Deuterium mainly exists in the form of D-H rather than D2.

[0030] One suitable water electrolysis method is alkaline water electrolysis. Hydrogen production by alkaline water electrolysis is a well-established technology up to the megawatt range for commercial levels. In alkaline water electrolysis, first at the cathode side, two water molecules of the alkaline solution (KOH / NaOH) are reduced to one hydrogen molecule (H2) and two hydroxyl ions (OH - ). The generated H2 diffuses from the cathode surface in gaseous form, and the hydroxyl ions (OH - ) move through the porous diaphragm to the anode under the influence of the electric field between the anode and the cathode, where they are discharged to half a molecule of oxygen (O2) and one molecule of water (H2O). Alkaline electrolysis operates at a lower temperature, for example 30 - 80 °C, using an alkaline aqueous solution (KOH / NaOH) as the electrolyte, and the concentration of the electrolyte is about 20% - 30%. The diaphragm in the center of the electrolysis cell separates the cathode and the anode, and similarly separates the generated gases from their respective electrodes, avoiding the mixing of the generated gases. However, alkaline electrolysis has negative aspects, such as a limited current density (less than 400 mA / cm 2 ), a low operating pressure, and low energy efficiency.

[0031] In one preferred embodiment of the method of the present invention, hydrogen is supplied by polymer electrolyte membrane water electrolysis. Variations of polymer electrolyte membrane water electrolysis are proton exchange membrane water electrolysis (PEMWE) and anion exchange membrane water electrolysis (AEMWE).

[0032] PEM water electrolysis was developed to overcome the drawbacks of alkaline water electrolysis. PEM water electrolysis technology is similar to PEM fuel cell technology where a solid polysulfonated membrane (Nafion®, fumapem®) is used as the electrolyte (proton conductor). These proton exchange membranes have many advantages, such as low gas permeability, high proton conductivity (0.1 ± 0.02 Scm -1) It has a thin thickness (20 - 300 μm) and enables high - voltage operation. From the perspectives of sustainability and environmental impact, PEM water electrolysis is one of the most preferred methods for converting renewable energy into high - purity hydrogen. PEM water electrolysis has significant advantages such as a compact design, high current density (2 Acm -2 super), high efficiency, fast response, operation at low temperatures (20 - 80 °C), and production of ultra - high - purity hydrogen. The prior - art electrode catalysts for PEM water electrolysis are high - activity noble metals, such as Pt / Pd for the hydrogen evolution reaction (HER) at the cathode and IrO2 / RuO2 for the oxygen evolution reaction (OER) at the anode.

[0033] One of the greatest advantages of PEM water electrolysis is the ability to operate at high current densities. This can reduce the operating costs of systems connected to highly dynamic energy sources, such as wind and solar power, which produce energy where sudden spikes in energy output are not captured. The polymer electrolyte enables the PEM water electrolysis device to operate with a very thin membrane (about 100 - 200 μm) while still allowing for high operating pressures, resulting in low ohmic losses caused mainly by proton conduction (0.1 S / cm) across the membrane and compressed hydrogen output.

[0034] PEM water electrolysis devices utilize a solid polymer electrolyte (SPE) to conduct protons from the anode to the cathode while electrically insulating the electrodes. Under standard conditions, the enthalpy required for water formation is 285.9 kJ / mol. Part of the energy required for the continuous electrolysis reaction is supplied by thermal energy, and the rest is supplied through electrical energy.

[0035] The half - reaction that occurs on the anode side of a PEM water electrolysis device is generally called the oxygen evolution reaction (OER). Here, liquid water reactants are supplied to the catalyst, where they are oxidized to oxygen, protons, and electrons.

[0036] The half-reaction that occurs on the cathode side of a PEM water electrolyzer is generally called the hydrogen evolution reaction (HER). Here, the protons that have migrated through the membrane are reduced to gaseous hydrogen.

[0037] PEM can be made from either a pure polymer membrane or a composite membrane in which other materials are embedded in a polymer matrix. One of the most common commercially available PEM materials is the fluoropolymer PFSA, or Nafion® from DuPont. Nafion® is an ionomer with a perfluorinated backbone like Teflon, but there are many other structural motifs used to make ionomers for proton exchange membranes. Many use polycyclic aromatic polymers, and others use partially fluorinated polymers.

[0038] An overview of hydrogen production by PEM water electrolysis is presented in S. Kumar and V. Himabindu, Material Science for Energy Technologies 2 (2019), pages 4442 - 4454.

[0039] An overview of hydrogen production by anion exchange membrane water electrolysis is presented in H. A. Miller et al., Sustainable Energy Fuels, 2020, 4, 2114 - 2133.

[0040] K. Harada et al., International Journal of Hydrogen Energy 45 (2020), pages 31389 - 31395, report a deuterium depletion of one - half to one - third in polymer electrolyte membrane water electrolysis. The separation factor β β = ([H] / [D]) 気体 / ([H] / [D]) 液体 (where "gas" is the evolved gas and "liquid" is water) was found to be 2 - 3 at a current density of 1.0 - 2.0 A cm corresponding to a stoichiometric number λ of 4 - 9 for a given anode water mass flow rate. The stoichiometric number λ is defined as follows: -2 The stoichiometric number λ is defined as follows: λ = V×ρ / (J / 2F×60×M H2O ) (wherein, V (mL / min -1 ) is the mass flow rate of water at the anode, F is the Faraday constant, J is the electrolysis current (A), ρ is the density of water (g / mL -1 ), and M H2O (g / mol -1 ) is the molar weight of water). The stoichiometric number λ of 10 means that fresh water in an amount 10 times the amount that can be theoretically consumed by electrolysis at a given electrolysis current is supplied to the anode.

[0041] H. Sato et al., International Journal of Hydrogen Energy 46 (2021), pages 33689 - 33695 reported that for anion exchange membrane water electrolysis, the deuterium concentration in the generated hydrogen gas is diluted to approximately 1 / 5 with respect to the feed water at λ = 4.

[0042] Therefore, deuterium in the generated hydrogen gas can be easily depleted to 1 / 2 to 1 / 5 with respect to the feed water in polymer electrolyte membrane water electrolysis. Higher depletion coefficients are possible depending on the electrolysis conditions (water flow, current density). Since the average deuterium content of water is approximately 150 ppm based on the total hydrogen content, the hydrogen supplied in step (a) of the method of the present invention can have a deuterium content of 30 - 75 ppm, or even lower, based on the total hydrogen content.

[0043] The electric power is generated at least partially from non - fossil renewable resources. In other words, since the combustion of natural gas produces far less carbon dioxide emissions per megajoule of electrical energy generated than the combustion of coal, a part of the electric power can still be generated from fossil fuels, preferably natural gas. However, the proportion of electrical energy generated from fossil fuels should be as low as possible, preferably 50% or less, preferably 30% or less, and most preferably 20% or less.

[0044] The power from non-fossil resources used in the water electrolysis according to the present invention can be generated by nuclear energy. Nuclear energy is considered renewable by the European Commission as long as certain preconditions (notably the safe long-term storage of nuclear waste) are met.

[0045] The power from non-fossil resources used in the water electrolysis according to the present invention is preferably generated from wind power, solar energy, biomass, hydropower and geothermal energy.

[0046] In one preferred embodiment of the method of the present invention, the power used in the water electrolysis is generated from hydropower. There are many forms of hydropower. Conventionally, hydropower generation is brought about by building large hydropower dams and reservoirs. Small hydropower systems are typically hydropower facilities that generate up to 50 MW of power. These are often used in small rivers or for less impactful development in larger rivers. A run-of-river hydropower plant obtains energy from a river without forming a large reservoir. Water is typically carried along the side of a river valley (using channels, pipes, and / or tunnels) until it is higher than the valley bottom, and then dropped through a penstock to drive a turbine.

[0047] Wave power that captures the energy of ocean surface waves and tidal power that converts the energy of ocean currents are two forms of hydropower with future potential.

[0048] In an even more preferred embodiment of the method of the present invention, the power used in the water electrolysis is generated from wind power. Wind power can be used to operate a wind turbine. Modern utility-scale wind turbines have a rated output in the range of about 600 kW to 9 MW. Since the power available from the wind is a function of the cube of the wind speed, as the wind speed increases, the power output increases up to the maximum output of a particular turbine. Areas where the wind is stronger and more consistent, such as offshore and high-altitude locations, are preferred locations for wind farms.

[0049] In one further preferred embodiment of the method of the present invention, the electric power used in the water electrolysis is generated from solar power, particularly preferably from a photovoltaic system. A photovoltaic system converts light into direct current (DC) by utilizing the photovoltaic effect. A concentrating solar power (CSP) system uses lenses or mirrors and a tracking system to concentrate a wide range of sunlight into a small beam. CSP Stirling has by far the highest efficiency among all solar energy technologies.

[0050] In one further preferred embodiment of the method of the present invention, the electric power used in the water electrolysis is generated from biomass. Biomass is biological material derived from living or recently living organisms. This most often refers to plant or plant-derived materials, particularly those called lignocellulosic biomass. As an energy source, biomass can be used directly, through combustion, to generate heat or electricity, or it can be used indirectly after converting the biomass into various forms of biofuels. The conversion of biomass into biofuels can be achieved by a variety of methods broadly classified into thermal, chemical, and biochemical methods. Wood was the largest biomass energy source in 2012; examples include forest residues - such as dead wood, branches, and tree stumps - yard trimmings, wood chips, and even municipal waste. Industrial biomass can be grown from a number of plant species including miscanthus, switchgrass, hemp, corn, poplar, willow, sorghum, sugarcane, bamboo, and eucalyptus to oil palm.

[0051] Plant energy is generated by crops specially cultivated for use as fuels that provide high biomass production per hectare with low input energy. Grains can be used as liquid transportation fuels, and straw can be burned to generate heat or electricity. Biomass can be converted into other usable forms of energy, such as methane gas or transportation fuels, such as ethanol and biodiesel. Food waste, as well as agricultural waste and manure, all emit methane gas, also known as landfill gas or biogas. Crops, such as corn and sugarcane, can be fermented to produce the transportation fuel, ethanol. Another transportation fuel, biodiesel, can be produced from food leftovers, such as vegetable oils and animal fats.

[0052] In step (b) of the method of the present invention, carbon dioxide is supplied. In a preferred embodiment, the carbon dioxide supplied in step (b) is captured from industrial flue gas or ambient air. All available capture technologies can be used.

[0053] CO2 capture is most cost-effective at point sources, such as large carbon-based energy facilities, industries with large CO2 emissions (such as cement manufacturing, steelmaking), natural gas processing, synthetic fuel plants, and fossil fuel-based hydrogen production plants. It is possible to extract CO2 from the air, but the low concentration of CO2 in the air compared to combustion sources makes the technology more complex and thus the method more expensive.

[0054] In some preferred embodiments, the carbon dioxide supplied in step (b) is captured from industrial flue gas.

[0055] In post-combustion capture, CO2 is removed after the combustion of fossil fuels - this is a scheme applied to fossil fuel power plants. CO2 is captured from the flue gas of power plants or other point sources. Absorption, or carbon scrubbing with amines, is the dominant capture technology. This is the only carbon capture technology that has been used industrially so far.

[0056] CO₂ adsorbs onto the MOF (metal-organic framework) through physical or chemical adsorption based on the porosity and selectivity of the MOF, leaving a gas stream poor in CO₂. Subsequently, temperature swing adsorption (TSA) or pressure swing adsorption (PSA) can be used to strip the CO₂ from the MOF and the MOF can be reused.

[0057] In some other preferred embodiments, the carbon dioxide supplied in step (b) is captured from ambient air.

[0058] Direct air capture (DAC) technology is a method of directly capturing carbon dioxide (CO₂) from ambient air and producing a concentrated stream of CO₂ for sequestration or utilization or production of carbon-neutral fuels. Carbon dioxide removal is achieved when ambient air contacts a chemical medium, typically an aqueous alkaline solvent or adsorbent. Subsequently, CO₂ is stripped from these chemical media through the application of energy (i.e., heat) to obtain a CO₂ stream that can undergo dehydration and compression, while simultaneously regenerating the chemical medium for reuse.

[0059] Dilute CO₂ can be efficiently separated using an anion exchange polymer resin called Marathon MSA, which absorbs air CO₂ when dry and releases it when exposed to moisture. Most of the energy for this method is supplied by the latent heat of the phase change of water. Another substance that can be used is an organometallic structure (or MOF). Membrane separation of CO₂ relies on a semipermeable membrane.

[0060] In step (c), hydrogen and carbon dioxide are reacted in the presence of a catalyst to form methanol.

[0061] An overview of suitable catalyst systems is presented by Kristian Stangeland, Hailong Li & Zhixin Yu, Energy, Ecology and Environment, Vol. 5, pp. 272-285 (2020). This method requires a multi-component catalyst system. The interaction between the components is essential for the high activity and selectivity of the catalyst for the conversion of CO2 to methanol. This has been demonstrated by numerous catalyst systems composed of various metals (i.e., Cu, Pd, Ni) and metal oxides (i.e., ZnO, ZrO2, In2O3). These composite systems can contain mixtures of metal phases, alloy phases, and metal oxide phases. The most promising catalyst systems for large-scale industrial processes are currently Cu-based catalysts and In-based catalysts due to their excellent catalytic performance.

[0062] The method for the synthesis of methanol from CO2 can be carried out, for example, by the method known from German Patent Application Publication No. 42 20 865, which produces methanol under the influence of a silent discharge.

[0063] Alternatively, methanol synthesis can also be carried out in a thermal reactor under pressure and high temperature and in the presence of a copper-based catalyst (German Patent Application Publication No. 43 32 789; German Patent Application Publication No. 19739773).

[0064] Typical catalysts are described in the literature, for example, by N. Kanoun et al., "Catalytic properties of Cu based catalysts containing Zr and / or V for methanol synthesis from a carbon dioxide and hydrogen mixture", CATALYSIS LETTERS 15, (1992) 231 - 235. Potential catalysts such as CuO / ZnO and Cu - ZnO - Al2O3 are also described by R.M. Navarro et al., "Methanol Synthesis from CO2: A Review of the Latest Developments in Heterogeneous Catalysis", Materials (2019), 12, 3902 and "Catalytic carbon dioxide hydrogenation to methanol: A review of recent studies", chemical engineering research and design 92 (2014) 2557 - 2567.

[0065] In recent years, a highly selective catalyst In2O3 / ZrO2 has been described for industrial - related conditions. Typical ranges of industrially relevant conditions for the hydrogenation of CO2 to methanol are T = 200 - 300 °C, P = 10 - 50 MPa, and a gas hourly space velocity (GHSV) of 16000 - 48000 h -1 -1 (Angew. Chem. Int. Ed. 2016, 55, 6261 - 6265).

[0066] Step (c) can be carried out in the presence of a copper - zinc - alumina catalyst. When using a copper - zinc - alumina catalyst, the preferred temperature ranges from 150 - 300 °C, preferably 175 - 300 °C, and the preferred pressure ranges from 10 - 150 bar (absolute).

[0067] Generally, ethylene is produced from methanol in the process of methanol to olefins (MTO process). Since this process involves the cleavage of C-H and C-D bonds respectively, the associated primary isotope effect becomes significant. In the MTO process, a mixture of ethylene and propylene is produced from methanol over a highly selective silicon aluminophosphate zeolite catalyst in a fluidized bed operation. The ratio of propylene to ethylene can be adjusted by selecting appropriate process conditions and can vary from 0.77 in the ethylene production mode and from 1.33 in the propylene production mode.

[0068] Since the kinetic isotope effect also exists in all subsequent manufacturing steps downstream of the value chain, the overall kinetic isotope effect is cumulative.

[0069] The deuterium content of hydrogen produced by electrolysis and the deuterium content of methanol obtained according to the present invention can be determined via mass spectrometry. When hydrogen is produced by electrolysis according to the present invention, its deuterium content is less than 90 ppm. Therefore, it is possible to determine whether methanol is produced from hydrogen by water electrolysis or conventionally, for example via synthesis gas from natural gas, based on the deuterium content of the methanol.

[0070] Methanol having a deuterium content of less than 90 ppm based on the total hydrogen content, which can be obtained according to the present invention, can be used for fuel applications, such as the production of MTBE / TAME, gasoline blending, the production of dimethyl ether and the production of biodiesel, for the production of formaldehyde, acetic acid, olefins, sodium methylate, methylation products, such as dimethylphenol, for the production of dimethyl terephthalate and methyl mercaptan.

[0071] The formaldehyde obtained from the methanol of the present invention can be further used, for example, to produce polyoxymethylene, butynediol, methylene diphenyl diisocyanate, neopentyl glycol, methacrylic acid, phenol formaldehyde resin, urea condensation resin, melamine resin, and acetone resin.

[0072] The acetic acid obtained from the methanol of the present invention can be further used, for example, to produce chloroacetic acid, acetic acid ester, methyl isopropyl ketone, and acetic anhydride.

[0073] The methyl mercaptan obtained from the methanol of the present invention can be further used, for example, to produce methyl mercaptopropionaldehyde, dimethyl disulfide, and methanesulfonic acid.

[0074] In particular, the present invention also relates to the use of methanol having a deuterium content of less than 90 ppm based on the total hydrogen content, obtainable according to the method of the present invention, for the production of formaldehyde, acetic acid, methylamine, methyl tert-butyl ether, methyl methacrylate, trimethylolpropane, methyl chloride, methylchlorosilane, and silicone.

[0075] The present invention also relates to a method for producing formaldehyde, comprising the above steps (a) to (c) and (d) obtaining formaldehyde by dehydrogenation or oxidation of the methanol obtained in step (c) and additional steps.

[0076] Formaldehyde is industrially produced by the catalytic oxidation of methanol. The most common catalysts are silver metal, iron(III) oxide, iron molybdate, or vanadium oxide. In the commonly used formox process, methanol and oxygen react at about 250 - 400 °C in the presence of iron oxide combined with molybdenum and / or vanadium according to the following chemical formula to produce formaldehyde: 2 CH3OH + O2 → 2 CH2O + 2 H2O

[0077] Silver-based catalysts typically operate at higher temperatures of about 650 °C. Two chemical reactions on this catalyst: the reaction shown above and the dehydration reaction simultaneously produce formaldehyde: CH3OH → CH2O + H2

[0078] Using the formaldehyde obtained in step (d), trimethylolpropane can be produced. In a further aspect, the present invention also relates to a method for producing trimethylolpropane, comprising steps (a) to (d) and (e) reacting the formaldehyde obtained in step (d) with butyraldehyde to obtain trimethylolpropane relates to a method comprising additional steps.

[0079] Trimethylolpropane is produced by a two-step process starting from the condensation of butyraldehyde and formaldehyde: CH3CH2CH2CHO + 2 CH2O → CH3CH2C(CH2OH)2CHO

[0080] The second step involves the Cannizzaro reaction: CH3CH2C(CH2OH)2CHO + CH2O + NaOH → CH3CH2C(CH2OH)3 + NaO2CH

[0081] The present invention also relates to a method for producing acetic acid, comprising steps (a) to (c) above and (d) reacting the methanol obtained in step (c) with carbon monoxide to obtain acetic acid relates to a method comprising additional steps.

[0082] Acetic acid can be produced by the carbonylation of methanol in step (d). This method involves iodomethane as an intermediate and is carried out in three steps. A metal carbonyl, which is a catalyst, is required for carbonylation (step 2). 1.CH3OH + HI → CH3I + H2O 2.CH3I + CO → CH3COI 3.CH3COI + H2O → CH3COOH + HI

[0083] There are two related methods for the carbonylation of methanol: the Monsanto process with a rhodium catalyst and the Cativa process with an iridium catalyst.

[0084] The Monsanto process operates at pressures of 30 - 60 atm and temperatures of 150 - 200 °C, giving a selectivity of over 99%. The catalytically active species is the anionic cis-[Rh(CO)2I2]. - The first organometallic step is the oxidative addition of methyl iodide to cis-[Rh(CO)2I2], - forming the six-coordinate species [(CH3)Rh(CO)2I3]. - This anion rapidly converts via the migration of the methyl group to an adjacent carbonyl ligand, giving the five-coordinate acetyl complex [(CH3CO)Rh(CO)I3]. - This five-coordinate complex then reacts with carbon monoxide to form a six-coordinate dicarbonyl complex, which undergoes reductive elimination to release acetyl iodide (CH3C(O)I). The catalytic cycle involves two non-organometallic steps: the conversion of methanol to methyl iodide and the hydrolysis of acetyl iodide to acetic acid and hydrogen iodide.

[0085] The Cativa process is a further method for producing acetic acid by the carbonylation of methanol. This technology is similar to the Monsanto process. This process is based on an iridium-containing catalyst, such as the complex [Ir(CO)2I2]. - The catalytic cycle of the Cativa process starts with the reaction of methyl iodide with a square-planar active catalyst species, giving the octahedral iridium(III) species [Ir(CO)2(CH3)I3]. -It forms. This oxidative addition reaction involves the formal insertion of the iridium(I) center into the carbon-iodine bond of methyl iodide. After ligand exchange of iodide with carbon monoxide, migratory insertion of carbon monoxide into the iridium-carbon bond results in the formation of a species with a coordinated acetyl ligand. The active catalyst species is regenerated by reductive elimination of acetyl iodide. Hydrolysis of acetyl iodide produces acetic acid product and hydroiodic acid in this step, which is then used to convert the starting material methanol to methyl iodide used in the first step.

[0086] The present invention also relates to a process for producing methylamine, comprising the above steps (a) to (c) and (d) reacting the methanol obtained in step (c) with ammonia to obtain methylamine and additional steps.

[0087] Step (d) can be carried out at 350 - 450 °C and 15 - 25 bar in the presence of a catalyst containing Al2O3 and SiO2.

[0088] The present invention also relates to a process for producing methyl tert-butyl ether, comprising the above steps (a) to (c) and (d) reacting the methanol obtained in step (c) with isobutene to obtain methyl tert-butyl ether and additional steps.

[0089] Step (d) can be carried out at 40 - 90 °C and 3 - 20 bar in the presence of an acidic ion exchanger.

[0090] The present invention also relates to a process for producing methyl methacrylate, comprising the above steps (a) to (c) and (d) reacting the methanol obtained in step (c) with methacrylic acid to obtain methyl methacrylate and additional steps.

Claims

1. A method for producing methanol having a deuterium content of less than 90 ppm based on the total hydrogen content, comprising: (a) supplying hydrogen having a deuterium content of less than 90 ppm based on the total hydrogen content by water electrolysis using electricity generated at least partially from non-fossil renewable resources; (b) supplying carbon dioxide; (c) reacting hydrogen and carbon dioxide in the presence of a catalyst to form methanol. A method comprising the above steps.

2. The method according to claim 1, wherein the electricity is generated from wind power, solar energy, biomass, hydropower and geothermal energy.

3. The method according to claim 1 or 2, wherein the hydrogen is supplied by polymer electrolyte membrane water electrolysis.

4. The method according to claim 3, wherein the hydrogen is supplied by proton exchange membrane water electrolysis (PEMWE) or anion exchange membrane water electrolysis (AEMWE).

5. The method according to any one of claims 1 to 4, wherein the carbon dioxide supplied in step (b) is captured from industrial flue gas.

6. The method according to any one of claims 1 to 4, wherein the carbon dioxide supplied in step (b) is captured from ambient air.

7. The method according to any one of claims 1 to 6, wherein step (c) is carried out in the presence of a copper-zinc-alumina catalyst.

8. The method according to any one of claims 1 to 7, wherein the hydrogen supplied in step (a) has a deuterium content of 30 to 75 ppm.

9. The carbon dioxide supplied in step (b) corresponds to a δ １３ C value of -10 to -2.5‰ １３The method according to any one of claims 1 to 8, having a C content.

10. Methanol having a deuterium content of less than 90 ppm based on the total hydrogen content, obtainable by the method according to any one of claims 1 to 9.

11. Methanol according to claim 10, having a deuterium content of 30 to 75 ppm based on the total hydrogen content.

12. -10 to -2.5‰ δ １３ Corresponding to the C value １３ Methanol according to claim 10 or 11, having a C content.

13. Use of the methanol according to any one of claims 10 to 12 for producing ethylene.

14. Use of the methanol according to any one of claims 10 to 12 for producing formaldehyde, acetic acid, methylamine, methyl tert.-butyl ether, methyl methacrylate, trimethylolpropane, methyl chloride, methylchlorosilane and silicone.

15. A method for producing formaldehyde, comprising steps (a) to (c) defined in any one of claims 1 to 9 and (d) obtaining formaldehyde by dehydrogenation or oxidation of the methanol obtained in step (c) A method comprising additional steps.

16. A method for producing trimethylolpropane, comprising steps (a) to (d) defined in claim 15 and (e) reacting the formaldehyde obtained in step (d) with butanal to obtain trimethylolpropane A method comprising additional steps.

17. A method for producing acetic acid, comprising steps (a) to (c) defined in any one of claims 1 to 9 and (d) Reacting the methanol obtained in step (c) with carbon monoxide to obtain acetic acid A method comprising additional steps.

18. A method for producing methylamine, comprising steps (a) to (c) defined in any one of claims 1 to 9 and (d) Reacting the methanol obtained in step (c) with ammonia to obtain methylamine A method comprising additional steps.

19. Step (d) is Al ２ O ３ and SiO ２ The method according to claim 18, wherein the reaction is carried out at 350 to 450 ° C and 15 to 25 bar in the presence of a catalyst containing

20. A method for producing methyl tert-butyl ether, comprising steps (a) to (c) defined in any one of claims 1 to 9 and (d) Reacting the methanol obtained in step (c) with isobutene to obtain methyl tert-butyl ether A method comprising additional steps.

21. The method according to claim 20, wherein step (d) is carried out at 40 to 90 ° C and 3 to 20 bar in the presence of an acidic ion exchanger.

22. A method for producing methyl methacrylate, comprising steps (a) to (c) defined in any one of claims 1 to 9 and (d) Reacting the methanol obtained in step (c) with methacrylic acid to obtain methyl methacrylate A method comprising additional steps.

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