Catalysts for the conversion of CO2-rich syngas to methanol and conventional syngas to dimethyl ether

Abstract

The present invention relates to a supported copper catalyst comprising Cu, Zn, Al, Zr, Si and O, the supported copper catalyst comprising elemental copper and exhibiting a Zn:Si atomic ratio in the range of 5:1 to 27:1, and a precursor of the catalyst. Furthermore, the present invention relates to a process for preparing each of the catalyst and catalyst precursor, and a method for producing a CO catalyst using each of the catalysts of the present invention. 2 The present invention relates to a process for the conversion of synthesis gas to methanol and a process for the conversion of synthesis gas to dimethyl ether.

Description

[Technical field]

[0001] The present invention relates to a process for preparing a supported Cu catalyst, a supported Cu catalyst and its use.Furthermore, the present invention relates to a catalyst precursor and a process for preparing a catalyst precursor.Furthermore, the present invention relates to a process for converting a CO2-containing synthesis gas to methanol using a supported catalyst, and a process for converting a synthesis gas to dimethyl ether using a supported catalyst. [Background technology]

[0002] Methanol and dimethyl ether (DME) are important compounds with widespread applications in the production of chemicals and in the energy sector, e.g. as replacements for gasoline or diesel fuel. The standard method for producing methanol is based on the conversion of conventional CO-rich and CO2-poor synthesis gas, where the main reaction is the conversion of CO to methanol by hydrogen according to equation (1): [ka]

[0003] In such typical conversion reactions, the partial pressure of CO2 and the partial pressure of H2O as a by-product of CO2 conversion are low. In such scenarios, non-demanding conditions are typically required to allow for long catalyst life. Conversion of CO2-rich synthesis gas is also possible, where CO2 reacts with hydrogen and is converted to methanol according to equation (2): [ka]

[0004] When using CO2-rich syngas, CO2 and H2 exhibit relatively high partial pressures. The application of CO2-rich syngas for conversion is particularly challenging due to the reverse water-gas shift reaction, which produces H2O according to equation (3): [ka]

[0005] Thus, demanding conditions are required for CO2-rich synthesis gas feed streams. Furthermore, in a further reaction that may occur in the presence of an acidic co-catalyst, the produced methanol reacts to DME in a one-step synthesis. Suitable acidic co-catalysts are disclosed in EP 3727681 A1. The reaction further increases the H2O concentration in the reactor as two CH3OH molecules undergo dehydration reaction to DME according to equation 4: [ka]

[0006] Therefore, special requirements must be met in order to carry out the conversion of CO2-rich synthesis gas or CO2-only feed streams. In particular, the catalysts used in said conversion must meet certain requirements, including catalytic stability. Furthermore, these catalysts must also be suitable for the reverse water-gas shift reaction (see equation (3) above).

[0007] Typically, Cu-based catalysts are used, where Cu can be supported on, for example, ZnO and Al2O3. In general, Cu-based catalysts are prepared by co-precipitation from metal salt solutions with a base solution, controlling the pH value, temperature and agitation. In most cases, hydroxycarbonate precursors of the metals used are obtained. Subsequent calcination results in a defined sequence of the respective metal oxides. The catalysts for methanol preparation are usually pelletized. They are then activated prior to use in the reactor. During activation, the Cu element is usually produced from CuO, while the other metal oxides remain mainly in their oxidation state.

[0008] Wu et al. have disclosed a study on optimizing the preparation conditions and improving the stability of a Cu / ZnO-based multicomponent catalyst for the synthesis of methanol from CO2 and H2. A Cu / ZnO-based multicomponent catalyst that can be prepared by coprecipitation is disclosed therein. In particular, it is disclosed that the addition of a SiO2 source leads to an increase in the stability of the Cu / ZnO-based catalyst. This catalyst can be used for the synthesis of methanol from CO2.

[0009] Based on the results of Wu et al., several catalysts have been developed. US Patent No. 6,048,820 relates to a Cu-based catalyst and its preparation method. The catalyst essentially comprises CuO, ZnO, Al2O3, SiO2. EP 2857095 A1 discloses a catalyst for methanol production, its preparation method, and a method for producing methanol, in which the catalyst comprises Cu, Zn, Al, and Si in a specific molar ratio.

[0010] WO 2020 / 212681A1 discloses a catalyst containing CuO, ZnO, Al2O3 and SiO2, and the catalyst has a molecular weight of 105m 2 / g and a BET specific surface area of ​​37 m 2 The catalysts have a Cu specific surface area of ​​more than 1000000 / g. The catalysts were tested for their activity and stability. Example 8 of WO 2020 / 212681 A1 discloses a catalyst that represents the current state of the art. The catalysts were tested under standard synthesis gas conditions (6% CO by volume, 6% CO2 by volume, 9% N2 by volume, and 79% H2 by volume) and low pressure (50 barg). Summary of the Invention [Problem to be solved by the invention]

[0011] Thus, there was a need for improved catalysts, particularly suitable for the conversion of CO2-rich syngas or CO2-only feed streams, especially CO2-rich syngas containing more than 10 vol.% CO2 and having a CO2 / CO molar ratio higher than 2. In particular, there was a need for catalysts that met demanding stability criteria. Furthermore, there was a need for new processes for the preparation of such improved catalysts.

[0012] The object of the present invention was therefore to provide a new process for the preparation of supported Cu catalysts as well as to provide improved supported Cu catalysts. In particular, the object of the present invention was to provide a highly stable supported Cu catalyst for the hydrogenation of CO2 and CO2-rich synthesis gas. It was an object to provide a supported Cu catalyst exhibiting improved stability under certain demanding conditions, in particular for the synthesis of methanol from CO2 according to the above formula (2) and for the synthesis of DME from methanol according to the above formula (4), in particular at temperatures in the range of 200-350°C and pressures in the range of 1-100 bara, preferably in the range of 40-85 bara, or pressures below 20 bara for the reverse water-gas shift reaction according to the above formula 3. [Means for solving the problem]

[0013] Thus, it has been surprisingly found that an improved supported Cu catalyst can be provided, which comprises Cu, Zn, Al, Zr, Si and O, contains elemental copper and exhibits a specific Zn:Si atomic ratio. Furthermore, it has been surprisingly found that a molded body prepared from the supported Cu catalyst of the present invention and having a specific trifurcated cross section exhibits a relatively lower pressure drop than a conventional tablet. Furthermore, it has been surprisingly found that such a catalyst can be prepared by a novel process, in particular in which the pH of the reaction mixture is controlled to be in a specific range. [Brief description of the drawings]

[0014] [Figure 1A] In Figure 1A, the powder XRD of the dried precipitate according to Example 16 obtained after coprecipitation and drying but before calcination is shown, in which the characteristic hydrotalcite phase is identified. [Figure 1B] FIG. 1B shows the powder XRD of the dried precipitate according to Example 12 obtained after co-precipitation and drying but before calcination. [Diagram 2] 1 shows the powder XRD of the calcined catalyst according to Example 16. In addition to the CuO and ZnO phases, a ZnAl2O4 spinel phase is shown to be formed from the hydrotalcite precursor. [Diagram 3]1 shows the powder XRD of the calcined and activated catalyst from Example 8. In addition to Cu metal, it shows that the typical ZnAl2O4 spinel phase is formed from the hydrotalcite precursor. Furthermore, in addition to ZnAl2O4, CuAl2O4 is likely present. [Figure 4A] FIG. 4A shows the results of the catalytic test according to Example IV for one-step dimethyl ether. [Figure 4B] 4 shows the results of a catalytic test according to Example IV for one-stage dimethyl ether. [Diagram 5] 1 shows a schematic diagram of a molded body having a trifurcated cross section, the trifurcated cross section having a geometric center C, each tip of the trifurcated cross section being rounded by an arc of a circle, and each corner of the trifurcated cross section being rounded by an arc of a circle. [Figure 6] 1 shows a schematic diagram of a molded body having a trifurcated cross section with rounded tips and rounded corners, the trifurcated cross section having a geometric center C, a tip base b, a tip height i, a height h, and a chord length k, each tip of the trifurcated cross section being rounded by an arc of a circle, and each corner of the trifurcated cross section being rounded by an arc of a circle. [Figure 7] 1 shows a schematic diagram of a molded body having a three-pronged cross section with rounded tips and rounded corners. The molded body has a height H. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Thus, the present invention provides (i) preparing a first aqueous solution S1 containing one or more copper-containing compounds, one or more zinc-containing compounds, one or more aluminum-containing compounds, and one or more zirconium-containing compounds, the first aqueous solution having a pH in the range of 0 to 5, preferably in the range of 0 to 4, more preferably in the range of 0.5 to 3.5, even more preferably in the range of 0.5 to 3, even more preferably in the range of 1 to 2.5, and even more preferably in the range of 1 to 2; (ii) preparing a second aqueous solution S2, the pH of which is adjusted to a value in the range of 8.5 to 12, preferably in the range of 8.5 to 11, more preferably in the range of 8.5 to 10.5, even more preferably in the range of 8.5 to 10, and even more preferably in the range of 8.5 to 9.5; (iii) preparing an aqueous mixture M containing solids suspended in water, comprising dosing S1 into S2 under stirring, during said dosing, the pH of the aqueous mixture M resulting from said dosing being maintained in the range of 8 to 10, preferably in the range of 8.5 to 9.5, more preferably the pH is maintained at a pH of 9±0.2; (iv) aging the aqueous mixture M obtained from (iii) for a time in the range of from 1 hour to 12 hours, preferably in the range of from 1 hour to 6 hours, more preferably in the range of from 1.5 hours to 3 hours, and even more preferably in the range of from 2 hours to 2.5 hours; and (v) separating the solids from the aqueous mixture obtained from (iv). 1. A process for the preparation of a catalyst precursor comprising Cu, Zn, Al, Zr, Si and O, preferably a catalyst precursor according to any of the particular and preferred embodiments of the present invention, comprising: one or more silicon-containing compounds are added for the preparation of S2 according to (ii), or one or more silicon-containing compounds are added to M during the aging of M according to (iv), or one or more silicon-containing compounds are added for the preparation of S2 according to (ii) and one or more silicon-containing compounds are added to the mixture M during the aging of M according to (iv).

[0016] Preferably, the one or more copper-containing compounds in (i) are one or more copper salts, preferably one or more Cu(II) salts, wherein the anion of the one or more copper salts is preferably selected from the group consisting of halide, carbonate, hydrogen carbonate, sulfate, hydrogen sulfate, hydroxide, nitrate, phosphate, hydrogen phosphate, dihydrogen phosphate, acetate, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, bromide, fluoride, hydrogen carbonate, hydrogen sulfate, nitric acid, dihydrogen phosphate, acetate, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, fluoride, nitric acid, acetic acid, and combinations of two or more thereof; More preferably, the anion of the copper salt or salts is chloride and / or nitrate, preferably nitrate; More preferably, the one or more copper-containing compounds comprises copper (II) nitrate, and more preferably, the one or more copper-containing compounds is copper (II) nitrate.

[0017] The one or more zinc-containing compounds in (i) are preferably one or more zinc salts, preferably one or more Zn(II) salts, wherein the anion of the one or more zinc salts is preferably selected from the group consisting of halide, carbonate, hydrogen carbonate, sulfate, hydrogen sulfate, hydroxide, nitrate, phosphate, hydrogen phosphate, dihydrogen phosphate, acetate, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, bromide, fluoride, hydrogen carbonate, hydrogen sulfate, nitric acid, dihydrogen phosphate, acetate, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, fluoride, nitric acid, acetic acid, and combinations of two or more thereof; More preferably, the anion of the zinc salt or salts is chloride and / or nitrate, preferably nitrate; More preferably, the one or more zinc-containing compounds comprises zinc(II) nitrate, and more preferably, the one or more zinc-containing compounds is zinc(II) nitrate.

[0018] The one or more aluminum-containing compounds in (i) are preferably one or more aluminum salts, wherein the anion of the one or more aluminum salts is preferably selected from the group consisting of halides, sulfates, hydroxides, nitrates, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, fluoride, sulfate, hydroxide, nitric acid, and combinations of two or more thereof; More preferably, the anion of the one or more aluminium salts is chloride and / or nitrate, preferably nitrate; More preferably, the one or more aluminum-containing compounds comprises aluminum nitrate, and more preferably, the one or more aluminum-containing compounds is aluminum nitrate.

[0019] The one or more zirconium-containing compounds in (i) are preferably one or more zirconium salts and / or zirconyl salts, preferably one or more Zr(IV) salts, wherein the anion of the one or more zirconium salts and / or zirconyl salts is preferably selected from the group consisting of halides, carbonates, hydrogen carbonates, sulfates, hydrogen sulfates, hydroxides, nitrates, phosphates, hydrogen phosphates, dihydrogen phosphates, acetates, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, bromide, fluoride, hydrogen carbonate, hydrogen sulfate, nitric acid, dihydrogen phosphate, acetate, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, fluoride, nitric acid, acetic acid, and combinations of two or more thereof; More preferably, the anion of the zirconium salt or salts is chloride and / or nitrate, preferably nitrate; More preferably, the one or more zirconium-containing compounds comprise zirconium(IV) nitrate and / or zirconyl nitrate, more preferably the one or more zirconium-containing compounds are zirconium(IV) nitrate and / or zirconyl nitrate, preferably zirconium(IV) nitrate.

[0020] Independently of one another, the one or more silicon-containing compounds of (ii) and (iv) are preferably selected from the group consisting of silicates, preferably from the group consisting of silicates, more preferably from the group consisting of alkali metal silicates and mixtures thereof, where the alkali metal is preferably selected from the group consisting of Li, Na, K, Rb, Cs and mixtures of two or more thereof, more preferably from the group consisting of Li, Na, K and mixtures of two or more thereof, more preferably the alkali metal is Na and / or K, preferably Na; More preferably, the one or more silicon-containing compounds comprise sodium silicate, preferably sodium water glass, more preferably Na2SiO3, and more preferably the one or more silicon-containing compounds are sodium silicate, preferably sodium water glass, more preferably Na2SiO3.

[0021] In (i), Cu, Zn, Al and Zr are preferably contained in S1 as their respective salts, preferably as their nitrates.

[0022] It is preferred that solution S1 obtained from (i) exhibits a Cu:Zn:Al:Zr molar ratio of (40-65):(10-25):(15-40):(0.2-10), preferably (45-62):(13-23):(18-35):(0.5-5), more preferably (50-59):(15-21):(22-30):(1-3), and further preferably (55-56):(17-19):(25-26):(1.4-1.6).

[0023] In (iii), the pH of the aqueous mixture M is preferably maintained in a pH range by metering a third aqueous solution S3 into the aqueous mixture M, the pH of S3 being equal to or greater than the pH of S2, and the pH of S3 is preferably in the range of 11 to 14, more preferably 12 to 14, more preferably 13 to 14.

[0024] In (iii), when the pH of the aqueous mixture M is maintained in the pH range by metering a third aqueous solution S3 into the aqueous mixture M, and the pH of S3 is equal to or greater than the pH of S2, it is preferred that S3 comprises one or more bases selected from the group consisting of Bronsted bases and Lewis bases, preferably the one or more bases are selected from the group consisting of inorganic bases and organic bases, more preferably selected from the group of inorganic bases, preferably the one or more bases are selected from the group consisting of hydroxides, carbonates, aluminates, and mixtures of two or more thereof, More preferably, it is selected from the group consisting of alkali metal hydroxides, alkali metal carbonates, alkali metal aluminates, and mixtures of two or more thereof; More preferably, it is selected from the group consisting of alkali metal carbonates, alkali metal aluminates, and mixtures of two or more thereof; The alkali metal is preferably selected from the group consisting of Li, Na, K, Rb, Cs and mixtures of two or more thereof; More preferably, it is selected from the group consisting of Li, Na, K and mixtures of two or more thereof; More preferably, the alkali metal is Na and / or K, preferably Na; More preferably, the one or more bases comprise sodium carbonate and / or sodium hydroxide, preferably sodium carbonate and sodium hydroxide, more preferably the one or more bases are sodium carbonate and / or sodium hydroxide, preferably sodium carbonate and sodium hydroxide.

[0025] It is preferred that the addition in (iii) is carried out continuously or intermittently, preferably continuously.

[0026] To maintain the pH of aqueous mixture M within the pH range of (iii), it is preferred that the pH of aqueous mixture M is semi-continuously or continuously monitored, and preferably is continuously monitored.

[0027] It is preferred that the agitation in (iii) is achieved by stirring.

[0028] It is preferred that the ageing in (iv) is carried out at a temperature in the range of 5-75°C, preferably 15-70°C, more preferably 25-65°C, more preferably 40-60°C, more preferably 45-55°C.

[0029] In (iv), it is preferred that sodium water glass is added after an ageing period in the range of 0.5 to 11.5 hours, preferably sodium water glass is optionally added after an ageing period of 1 hour.

[0030] It is preferred that the aqueous mixture M obtained from (iii) or the aged aqueous mixture obtained from (iv) exhibits a Cu:Zn:Al:Zr:Si molar ratio in the range of (40-65):(10-25):(15-40):(0.2-10):(0.1-5), preferably (45-62):(13-23):(18-35):(0.5-5):(0.3-4.5), more preferably (50-59):(15-21):(22-30):(1-3):(0.8-4), more preferably (55-56):(17-19):(25-26):(1.4-1.6):(1.2-3.6).

[0031] It is preferred that the separation in (v) is accomplished by filtration.

[0032] The process is (vi) washing the solid obtained from (v); and / or, preferably, (vii) Drying the solid obtained from (v) or (vi) at a temperature in the range of preferably 80 to 150° C., preferably 90 to 140° C., more preferably 105 to 130° C., and even more preferably 115 to 125° C. It is preferred that the composition further comprises:

[0033] If the process further comprises (vi), it is preferred that the washing in (vi) is carried out with deionized water.

[0034] When the process further comprises (vi) and / or (vii), it is preferred that the drying in (vii) is carried out for a time in the range of 1 hour to 48 hours, preferably in the range of 6 hours to 36 hours, more preferably in the range of 12 hours to 30 hours, and even more preferably in the range of 18 hours to 24 hours.

[0035] The process is (ix) Calcining the solid obtained from (v), (vi) or (vii) at a temperature preferably in the range of 400 to 750° C., preferably in the range of 500 to 700° C., more preferably in the range of 550 to 650° C. It is preferred that the composition further comprises:

[0036] When the process further comprises (ix), it is preferred that the calcination in (ix) is carried out for a time in the range of 0.5 to 12 hours, preferably 1 to 6 hours, more preferably 1.5 to 2.5 hours.

[0037] If the process further comprises (ix), it is preferred that the calcination in (ix) is carried out in an atmosphere comprising oxygen, preferably in an atmosphere comprising air, more preferably the calcination in (ix) is carried out in air.

[0038] The present invention also relates to a catalyst precursor comprising Cu, Zn, Al, Zr, Si and O, preferably according to any of the particular and preferred embodiments of the present invention, obtainable or obtained according to the process of any of the particular and preferred embodiments of the present invention.

[0039] The present invention also relates to a process for the preparation of a supported copper catalyst comprising Cu, Zn, Al, Zr, Si and O, preferably according to any of the specific and preferred embodiments of the present invention, wherein the catalyst comprises elemental copper, (1) preparing a catalyst precursor comprising Cu, Zn, Al, Zr, Si and O according to any of the processes of the specific and preferred embodiments of the present invention for the preparation of a catalyst precursor comprising a calcination step (ix); (2) reducing the catalyst precursor obtained from (1) in a hydrogen-containing atmosphere to obtain a supported copper catalyst; The present invention relates to a process comprising:

[0040] The reduction in (2) is preferably carried out at a temperature in the range of 150 to 350°C, preferably 170 to 300°C, and more preferably 170 to 230°C.

[0041] The atmosphere (2) preferably contains 0.25 to 80 volume % H2, preferably 0.5 to 50 volume % H2, more preferably 0.5 to 30 volume % H2, even more preferably 1 to 10 volume % H2, and even more preferably 2 to 5 volume % H2.

[0042] The atmosphere (2) preferably contains 99.75 to 20% by volume of an inert gas, more preferably 99.5 to 50% by volume, even more preferably 99.5 to 70% by volume, even more preferably 99 to 90% by volume, and even more preferably 98 to 95% by volume.

[0043] When the atmosphere in (2) contains 99.75 to 20% by volume of an inert gas, the inert gas is selected from the group consisting of a rare gas, nitrogen gas, and methane, preferably contains one or more gases selected from the group consisting of He, Ar, Ne, N2, and CH4, more preferably contains N2, and even more preferably is N2.

[0044] The present invention also relates to a supported copper catalyst comprising Cu, Zn, Al, Zr, Si and O, preferably according to any of the particular and preferred embodiments of the present invention, obtainable or obtained according to any of the particular and preferred embodiments of the inventive process for its preparation, wherein the catalyst comprises elemental copper.

[0045] The present invention also relates to a catalyst precursor comprising Cu, Zn, Al, Zr, Si and O, preferably obtainable or obtained according to any of the particular and preferred embodiments of the inventive process for its preparation, wherein the catalyst precursor exhibits a Zn:Si atomic ratio in the range of 5:1 to 27:1, preferably in the range of 5.5:1 to 25:1, more preferably in the range of 6:1 to 20:1, more preferably in the range of 6.5:1 to 15:1, more preferably in the range of 7:1 to 12:1, more preferably in the range of 7.5:1 to 10:1, more preferably in the range of 8:1 to 9:1.

[0046] It is preferred that the catalyst precursor comprises one or more hydroxycarbonate mixed oxides comprising two or more of Cu, Zn and Al, preferably two or more of Cu, Zn, Al and Zr, more preferably the catalyst precursor comprises one or more hydroxycarbonate mixed oxides of Cu, Zn and Al, preferably Cu, Zn, Al and Zr.

[0047] Preferably, the catalyst precursor comprises CuO.

[0048] The catalyst precursor is Zr-modified Cu3Zn3Al2(OH) 16 CO3, preferably Zr modified Cu3Zn3Al2(OH) 16 CO3·4H2O is preferred. Here, Zr-modified Cu3Zn3Al2(OH) 16 The 003 reflection in the X-ray diffraction diagram of CO3 is Cu3Zn3Al2(OH) 16 Compared to the X-ray diffraction pattern of CO3, it is shifted to higher °2θ values, and Zr-modified Cu3Zn3Al2(OH) 16 The 003 reflection in the X-ray diffraction diagram of CO3 is located in the range of 11 to 13.5° 2θ, the X-ray diffraction diagram being preferably determined according to Reference Example 2.

[0049] Alternatively, the catalyst precursor, preferably the catalyst precursor obtainable or obtained according to any of the processes of the particular and preferred embodiments of the present invention including the calcination step (ix), preferably comprises one or more oxides of Cu, Zn, Al, Zr and Si oxides, the catalyst precursor preferably comprises one or more oxides selected from the group consisting of CuO, ZnO, ZnAl2O4 and CuAl2O4, more preferably the catalyst precursor comprises CuO, ZnO and ZnAl2O4 or CuO, ZnO, ZnAl2O4 and CuAl2O4. According to said preferred embodiment, it is further preferred that the catalyst precursor comprises an amount of CuO in the range of 50-70% by weight, calculated as the oxide CuO, based on the sum of the weights of the oxides of Cu, Zn, Al, Zr and Si calculated as CuO, ZnO, Al2O3, ZrO2 and SiO2 contained in the catalyst precursor. The catalyst precursor preferably contains CuO in an amount ranging from 55 to 65% by weight, more preferably from 58 to 62% by weight.Furthermore, according to the preferred embodiment, it is further preferred that the catalyst precursor contains SiO2.

[0050] It is preferred that the catalyst precursor exhibits a Cu:Zn:Al:Zr:Si molar ratio of (40-65):(10-25):(15-40):(0.2-10):(0.1-5), preferably (45-62):(13-23):(18-35):(0.5-5):(0.3-4.5), more preferably (50-59):(15-21):(22-30):(1-4):(0.8-4), more preferably (55-56):(17-19):(25-26):(1.4-3):(1.2-3.6).

[0051] It is preferable that 95 to 100% by weight, more preferably 97 to 100% by weight, even more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, even more preferably 99.5 to 100% by weight, and even more preferably 99.9 to 100% by weight of the catalyst precursor is composed of Cu, Zn, Al, Zr, Si, and O.

[0052] The present invention also relates to a supported copper catalyst comprising Cu, Zn, Al, Zr, Si and O, preferably obtainable or obtained according to any of the particular and preferred embodiments of the inventive process for its preparation, wherein the catalyst comprises elemental copper and wherein the catalyst exhibits a Zn:Si atomic ratio in the range of 5:1 to 27:1, preferably in the range of 5.5:1 to 25:1, more preferably in the range of 6:1 to 20:1, more preferably in the range of 6.5:1 to 15:1, more preferably in the range of 7:1 to 12:1, more preferably in the range of 7.5:1 to 10:1, more preferably in the range of 8:1 to 9:1.

[0053] It is preferred that the supported copper catalyst comprises one or more oxides of Zn, Al, Zr and Si, and the supported copper catalyst preferably comprises one or more oxides selected from the group consisting of ZnO, ZnAl2O4 and CuAl2O4, and more preferably the supported copper catalyst comprises ZnO and ZnAl2O4, or ZnO and CuAl2O4, or ZnO, ZnAl2O4 and CuAl2O4.

[0054] Supported copper catalyst is 130m 2 It is preferable that the BET surface area is 60 to 130 m / g or less, and more preferably 60 to 130 m 2 The BET surface area is preferably determined according to Reference Example 1.

[0055] The supported copper catalyst is 5 to 15 m 2 / g, preferably 10 to 13 m 2 / g, the copper surface area being determined according to Example 3.

[0056] It is preferred that the supported copper catalyst comprises SiO2.

[0057] The supported copper catalyst preferably exhibits a Cu:Zn:Al:Zr:Si molar ratio of (40-65):(10-25):(15-40):(0.2-10):(0.1-5), preferably (45-62):(13-23):(18-35):(0.5-5):(0.3-4.5), more preferably (50-59):(15-21):(22-30):(1-4):(0.8-4), and more preferably (55-56):(17-19):(25-26):(1.4-3):(1.2-3.6).

[0058] It is preferable that 95 to 100% by weight, preferably 97 to 100% by weight, more preferably 98 to 100% by weight, even more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight, and more preferably 99.9 to 100% by weight of the supported copper catalyst is composed of Cu, Zn, Al, Zr, Si and O.

[0059] The supported copper catalyst is preferably in the form of a shaped body having a height H and a three-pronged cross section with rounded tips and rounded corners. Schematic diagrams of such a shaped body are shown in Figures 6 and 7, and the height H of the shaped body is shown in Figure 7.

[0060] According to the invention, a shaped body is understood as a three-dimensional entity resulting from a shaping process. The term "shaped body" is therefore used synonymously with the term "shaped body".

[0061] When the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, the tip base b of the trifurcated cross section (see FIG. 6) is preferably in the range of 2.00 to 2.60 mm, more preferably in the range of 2.10 to 2.50 mm, more preferably in the range of 2.20 to 2.40 mm, and more preferably in the range of 2.25 to 2.35 mm.

[0062] Furthermore, when the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, the tip height i of the trifurcated cross section (see FIG. 6) is preferably in the range of 2.55 to 3.15 mm, more preferably in the range of 2.65 to 3.05 mm, even more preferably in the range of 2.75 to 2.95 mm, and even more preferably in the range of 2.80 to 2.90 mm.

[0063] Furthermore, when the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, the height h of the trifurcated cross section (see FIG. 6) is preferably in the range of 5.40 to 6.00 mm, more preferably in the range of 5.50 to 5.90 mm, even more preferably in the range of 5.60 to 5.80 mm, and even more preferably in the range of 5.65 to 5.75 mm.

[0064] Furthermore, when the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, the cord length k of the trifurcated cross section (see FIG. 6) is preferably in the range of 6.00 to 6.60 mm, more preferably in the range of 6.10 to 6.50 mm, even more preferably in the range of 6.20 to 6.40 mm, and even more preferably in the range of 6.25 to 6.35 mm.

[0065] Furthermore, when the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, it is preferred that the trifurcated cross section has an interior angle α (see FIG. 6) in the range of 5° to 19°, more preferably in the range of 8° to 16°, more preferably in the range of 10° to 14°, and even more preferably in the range of 11° to 13°.

[0066] In the context of the present invention, the interior angle α defines the relationship of two axes forming part of the tips of a trifurcated cross section, each tip being rounded according to the present invention, in particular by an arc of a circle having a particular radius.

[0067] Furthermore, when the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, it is preferable that each tip of the trifurcated cross section is rounded by an arc of a circle having a radius, independently of each other, in the range of 0.65 to 1.25 mm, more preferably in the range of 0.75 to 1.15 mm, even more preferably in the range of 0.85 to 1.05 mm, and even more preferably in the range of 0.90 to 1.00 mm.

[0068] Furthermore, when the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, the distances between the geometric center C of the trifurcated cross section (see FIG. 6) and each tip of the trifurcated cross section are independently in the range of 2.0 to 5.0 mm, more preferably in the range of 2.7 to 4.3 mm, more preferably in the range of 3.2 to 3.8 mm, and more preferably in the range of 3.4 to 3.6 mm.

[0069] Furthermore, when the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, it is preferable that the trifurcated cross section has an exterior angle β (see Figure 6) in the range of 125° to 155°, more preferably in the range of 135° to 145°, even more preferably in the range of 127° to 137°, and even more preferably in the range of 130° to 134°.

[0070] In the context of the present invention, the exterior angle β defines the relationship of the axis of one tip to the axis of the adjacent tip of the trifurcated cross section, thereby forming an angle. According to the present invention, each corner is rounded, in particular by an arc of a circle having a particular radius.

[0071] Furthermore, when the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, it is preferable that each corner of the trifurcated cross section is rounded by an arc of a circle having a radius, independently of each other, in the range of 0.65 to 1.25 mm, more preferably in the range of 0.75 to 1.15 mm, even more preferably in the range of 0.85 to 1.05 mm, and even more preferably in the range of 0.90 to 1.00 mm.

[0072] Furthermore, when the supported copper catalyst is in the form of a molded body having a height H and a trifurcated cross section with rounded tips and rounded corners, the height H of the molded body is preferably in the range of 3.0 to 11.0 mm, more preferably in the range of 3.5 to 10.5 mm, even more preferably in the range of 4.5 to 9.5 mm, more preferably in the range of 5.5 to 8.5 mm, and even more preferably in the range of 6.5 to 7.5 mm.

[0073] The present invention also provides a method for converting a CO2-containing synthesis gas into methanol, comprising the steps of: (A) providing a supported copper catalyst according to any of the specific and preferred embodiments of the present invention; (B) preparing a gas mixture comprising CO, H2, and CO2; (C) contacting the supported copper catalyst provided in (A) with the gas mixture prepared in (B) at a temperature in the range of 200 to 350°C, preferably in the range of 230 to 260°C. The present invention also relates to a method comprising the steps of:

[0074] The contacting in (B) is preferably carried out at a pressure in the range of 1 to 100 bara, preferably in the range of 40 to 85 bara, more preferably in the range of 70 to 82 bara, and even more preferably in the range of 74 to 81 bara.

[0075] It is preferred that the gas mixture prepared in (B) contains 10 to 24 vol. %, preferably 11 to 20 vol. %, more preferably 12 to 19 vol. %, and even more preferably 15 to 18 vol. % CO2.

[0076] It is preferred that the gas mixture prepared in (B) contains 0.5 to 7 vol. %, preferably 0.8 to 4 vol. %, and more preferably 1 to 2 vol. % CO.

[0077] It is preferred that the gas mixture prepared in (B) exhibits a CO2:CO molar ratio in the range of 2-20, preferably 3-17, more preferably 5-15, and even more preferably 7-13.

[0078] The gas mixture prepared in (B) preferably contains 50 to 90% by volume, preferably 55 to 87% by volume, more preferably 60 to 85% by volume, and even more preferably 65 to 83% by volume of H2.

[0079] It is preferable that the gas mixture prepared in (B) contains 0.1 to 40 volume %, preferably 0.3 to 30 volume %, more preferably 0.5 to 25 volume %, even more preferably 0.8 to 20 volume %, and still more preferably 1 to 15 volume % of an inert gas.

[0080] When the gas mixture prepared in (B) contains 0.1 to 40 volume % of an inert gas, the inert gas is selected from the group consisting of a rare gas and a nitrogen gas, preferably selected from the group consisting of He, Ar, Ne, CH4 and N2, more preferably containing one or more gases selected from the group consisting of Ar, CH4 and N2, even more preferably the inert gas contains CH4 and N2, and even more preferably the inert gas is CH4 and N2.

[0081] The present invention also provides a method for converting synthesis gas to dimethyl ether, comprising the steps of: (A) combining a supported copper catalyst according to any of the specific and preferred embodiments of the present invention with an acidic co-catalyst; (B) preparing a gas mixture comprising CO, H2, and CO2; (C) contacting the catalyst mixture provided in (A) with the gas mixture prepared in (B) at a temperature in the range of 200-300°C, preferably 250-270°C. The present invention relates to a method comprising the steps of:

[0082] In the sense of the present invention, an acidic cocatalyst is a solid catalyst comprising acid sites. In principle, any solid catalyst comprising acid sites may be used, provided that it is suitable for catalyzing the dehydration of methanol to dimethyl ether. According to the present invention, it is preferred that the acidic cocatalyst is a catalyst comprising or consisting of methanol-dimethyl ether catalyst particles according to any of the specific or preferred embodiments disclosed in EP 3727681 A1, i.e. a catalyst comprising or consisting of methanol-dimethyl ether catalyst particles comprising a catalytically active component selected from the group consisting of: (i) Aluminum oxides such as acidic aluminum silicates, silicates, zeolites, gamma-alumina, etc. or mixtures thereof; (ii) Acid aluminum hydroxide, aluminum oxide hydroxide and gamma-aluminum oxide containing 0.1 to 20% by weight of niobium, tantalum, phosphorus or boron based on the catalytically active component, or a mixture thereof; or (iii) Acidic niobium oxide, tantalum oxide, titanium oxide, zirconium oxide, silicon oxide, aluminum phosphate, niobium phosphate, or mixtures thereof. wherein the methanol-dimethyl ether catalyst particles further comprise at least one transition metal, including any preferred or particularly preferred embodiments thereof as disclosed in the claims and specification of EP 3727681 A1.

[0083] It is preferred that the contacting in (B) is carried out at a pressure in the range of 1 to 100 bara, preferably in the range of 50 to 85 bara, more preferably in the range of 60 to 75 bara.

[0084] The gas mixture prepared in (B) preferably contains CO2 in an amount of 25% by volume or less, preferably 2 to 15% by volume, more preferably 3 to 10% by volume, and even more preferably 4 to 6% by volume.

[0085] It is preferred that the gas mixture prepared in (B) contains 2 to 30 vol. %, preferably 5 to 29 vol. %, more preferably 10 to 28 vol. %, even more preferably 20 to 27 vol. %, and even more preferably 24 to 26 vol. % CO.

[0086] It is preferred that the gas mixture prepared in (B) exhibits a CO2:CO molar ratio of 5 or less, preferably in the range of 0.05 to 2, more preferably in the range of 0.05 to 1, more preferably in the range of 0.1 to 0.5, and even more preferably in the range of 0.15 to 0.25.

[0087] It is preferred that the gas mixture prepared in (B) contains 30-70% by volume H2, preferably 40-65% by volume, more preferably 50-60% by volume.

[0088] It is preferred that the gas mixture prepared in (B) contains 1 to 30% by volume, preferably 5 to 25% by volume, and more preferably 10 to 20% by volume of the inert gas.

[0089] When the gas mixture prepared in (B) contains 1 to 30 volume % of an inert gas, the inert gas is selected from the group consisting of a rare gas and a nitrogen gas, preferably contains one or more gases selected from the group consisting of He, Ar, Ne, CH4 and N2, more preferably the inert gas contains CH4 and N2, and even more preferably the inert gas is N2.

[0090] The present invention also relates to the use of a supported copper catalyst according to any of the particular and preferred embodiments of the present invention as a reverse water-gas shift catalyst in the reforming of methanol, the conversion of CO2-containing synthesis gas to methanol, the reforming of dimethyl ether, and the conversion of synthesis gas to dimethyl ether.

[0091] The unit bara is 10 5 It means absolute pressure equivalent to Pa.

[0092] The present invention is further illustrated by the following series of embodiments and combinations of embodiments, which are derived from the indicated dependencies and back references. In particular, it should be noted that in each instance where a range of embodiments is mentioned in conjunction with terms such as "any one of embodiments (1) to (4)", it means that all embodiments within this range are expressly disclosed to those skilled in the art, i.e., the usage of this term should be understood by those skilled in the art to be equivalent to "any one of embodiments (1), (2), (3) and (4)". Furthermore, it should be expressly noted that the following series of embodiments represents a preferred configuration of the present specification, which is directed to the general and preferred aspects of the present invention, rather than a series of claims defining the scope of protection.

[0093] 1. (i) preparing a first aqueous solution S1 containing one or more copper-containing compounds, one or more zinc-containing compounds, one or more aluminum-containing compounds, and one or more zirconium-containing compounds, the first aqueous solution having a pH in the range of 0 to 5, preferably in the range of 0 to 4, more preferably in the range of 0.5 to 3.5, even more preferably in the range of 0.5 to 3, even more preferably in the range of 1 to 2.5, and even more preferably in the range of 1 to 2; (ii) preparing a second aqueous solution S2, the pH of which is adjusted to a value in the range of 8.5 to 12, preferably in the range of 8.5 to 11, more preferably in the range of 8.5 to 10.5, even more preferably in the range of 8.5 to 10, and even more preferably in the range of 8.5 to 9.5; (iii) preparing an aqueous mixture M containing solids suspended in water, comprising dosing S1 into S2 under stirring, during said dosing, the pH of the aqueous mixture M resulting from said dosing being maintained in the range of 8 to 10, preferably in the range of 8.5 to 9.5, more preferably the pH is maintained at a pH of 9±0.2; (iv) aging the aqueous mixture M obtained from (iii) for a time in the range of from 1 hour to 12 hours, preferably in the range of from 1 hour to 6 hours, more preferably in the range of from 1.5 hours to 3 hours, and even more preferably in the range of from 2 hours to 2.5 hours; and (v) separating the solids from the aqueous mixture obtained from (iv). A process for preparing a catalyst precursor comprising Cu, Zn, Al, Zr, Si and O, preferably according to any one of embodiments 31 to 39, comprising: one or more silicon-containing compounds are added for the preparation of S2 according to (ii), or one or more silicon-containing compounds are added to M during aging of M according to (iv), or one or more silicon-containing compounds are added for the preparation of S2 according to (ii) and one or more silicon-containing compounds are added to mixture M during aging of M according to (iv).

[0094] 2. the one or more copper-containing compounds in (i) are one or more copper salts, preferably one or more Cu(II) salts, the anion of the one or more copper salts being preferably selected from the group consisting of halides, carbonates, bicarbonates, sulfates, hydrogen sulfates, hydroxides, nitrates, phosphates, hydrogen phosphates, dihydrogen phosphates, acetates, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, bromide, fluoride, hydrogen carbonate, hydrogen sulfate, nitric acid, dihydrogen phosphate, acetate, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, fluoride, nitric acid, acetic acid, and combinations of two or more thereof; More preferably, the anion of the copper salt or salts is chloride and / or nitrate, preferably nitrate; More preferably, the one or more copper-containing compounds comprises copper(II) nitrate, more preferably the one or more copper-containing compounds is copper(II) nitrate.

[0095] 3. The one or more zinc-containing compounds in (i) are one or more zinc salts, preferably one or more Zn(II) salts, and the anion of the one or more zinc salts is preferably selected from the group consisting of halide, carbonate, bicarbonate, sulfate, hydrogen sulfate, hydroxide, nitrate, phosphate, hydrogen phosphate, dihydrogen phosphate, acetate, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, bromide, fluoride, hydrogen carbonate, hydrogen sulfate, nitric acid, dihydrogen phosphate, acetate, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, fluoride, nitric acid, acetic acid, and combinations of two or more thereof; More preferably, the anion of the zinc salt or salts is chloride and / or nitrate, preferably nitrate; More preferably, the one or more zinc-containing compounds comprises zinc(II) nitrate, more preferably the one or more zinc-containing compounds is zinc(II) nitrate.

[0096] 4. The one or more aluminum-containing compounds in (i) are one or more aluminum salts, and the anion of the one or more aluminum salts is preferably selected from the group consisting of halides, sulfates, hydroxides, nitrates, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, fluoride, sulfate, hydroxide, nitric acid, and combinations of two or more thereof; More preferably, the anion of the one or more aluminium salts is chloride and / or nitrate, preferably nitrate; More preferably, the one or more aluminum-containing compounds comprise aluminum nitrate, more preferably, the one or more aluminum-containing compounds are aluminum nitrate.

[0097] 5. The one or more zirconium-containing compounds in (i) are one or more zirconium salts and / or zirconyl salts, preferably one or more Zr(IV) salts, and the anion of the one or more zirconium salts and / or zirconyl salts is preferably selected from the group consisting of halides, carbonates, hydrogen carbonates, sulfates, hydrogen sulfates, hydroxides, nitrates, phosphates, hydrogen phosphates, dihydrogen phosphates, acetates, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, bromide, fluoride, hydrogen carbonate, hydrogen sulfate, nitric acid, dihydrogen phosphate, acetate, and combinations of two or more thereof; More preferably, it is selected from the group consisting of chloride, fluoride, nitric acid, acetic acid, and combinations of two or more thereof; More preferably, the anion of the zirconium salt or salts is chloride and / or nitrate, preferably nitrate; More preferably, the one or more zirconium-containing compounds comprise zirconium(IV) nitrate and / or zirconyl nitrate, more preferably the one or more zirconium-containing compounds are zirconium(IV) nitrate and / or zirconyl nitrate, preferably zirconium(IV) nitrate.

[0098] 6. Independently from each other, the one or more silicon-containing compounds of (ii) and (iv) are selected from the group consisting of silicates, preferably from the group consisting of silicates, more preferably from the group consisting of alkali metal silicates and mixtures thereof, the alkali metal is preferably selected from the group consisting of Li, Na, K, Rb, Cs and mixtures of two or more thereof, more preferably from the group consisting of Li, Na, K and mixtures of two or more thereof, more preferably the alkali metal is Na and / or K, preferably Na; More preferably, the one or more silicon-containing compounds comprise sodium silicate, preferably sodium water glass, more preferably Na2SiO3; more preferably, the one or more silicon-containing compounds are sodium silicate, preferably sodium water glass, more preferably Na2SiO3. The process according to any one of the preceding claims.

[0099] 7. The process of any one of the preceding embodiments, wherein in (i), Cu, Zn, Al and Zr are included in S1 as their respective salts, preferably as their nitrates.

[0100] 8. The process according to any one of the preceding embodiments, wherein the solution S1 obtained from (i) exhibits a Cu:Zn:Al:Zr molar ratio of (40-65):(10-25):(15-40):(0.2-10), preferably (45-62):(13-23):(18-35):(0.5-5), more preferably (50-59):(15-21):(22-30):(1-3), and even more preferably (55-56):(17-19):(25-26):(1.4-1.6).

[0101] 9. The process according to any one of the preceding embodiments, wherein in (iii), the pH of the aqueous mixture M is maintained in a pH range by metering a third aqueous solution S3 into the aqueous mixture M, the pH of S3 being equal to or greater than the pH of S2, and the pH of S3 is preferably in the range of 11-14, more preferably 12-14, more preferably 13-14.

[0102] 10. S3 comprises one or more bases selected from the group consisting of Bronsted bases and Lewis bases, the one or more bases being selected from the group consisting of inorganic bases and organic bases, more preferably selected from the group of inorganic bases, preferably the one or more bases being selected from the group consisting of hydroxides, carbonates, aluminates, and mixtures of two or more thereof; More preferably, it is selected from the group consisting of alkali metal hydroxides, alkali metal carbonates, alkali metal aluminates, and mixtures of two or more thereof; More preferably, it is selected from the group consisting of alkali metal carbonates, alkali metal aluminates, and mixtures of two or more thereof; The alkali metal is preferably selected from the group consisting of Li, Na, K, Rb, Cs and mixtures of two or more thereof; More preferably, it is selected from the group consisting of Li, Na, K and mixtures of two or more thereof; More preferably, the alkali metal is Na and / or K, preferably Na; More preferably, the one or more bases comprise sodium carbonate and / or sodium hydroxide, preferably sodium carbonate and sodium hydroxide, more preferably the one or more bases are sodium carbonate and / or sodium hydroxide, preferably sodium carbonate and sodium hydroxide.

[0103] 11. The process according to any one of the preceding embodiments, wherein the addition in (iii) is carried out continuously or intermittently, preferably continuously.

[0104] 12. The process according to any one of the preceding embodiments, wherein the pH of aqueous mixture M is monitored semi-continuously or continuously, preferably continuously, to maintain the pH of aqueous mixture M in the pH range of (iii).

[0105] 13. The process of any one of the preceding embodiments, wherein the agitation in (iii) is achieved by stirring.

[0106] 14. The process according to any one of the preceding embodiments, wherein the ageing in (iv) is carried out at a temperature in the range of 5 to 75°C, preferably 15 to 70°C, more preferably 25 to 65°C, more preferably 40 to 60°C, more preferably 45 to 55°C.

[0107] 15. The process according to any one of the preceding embodiments, wherein in (iv), sodium water glass is added after an aging period ranging from 0.5 to 11.5 hours, preferably sodium water glass is optionally added after an aging period of 1 hour.

[0108] 16. The process according to any one of the preceding embodiments, wherein the aqueous mixture M obtained from (iii) or the aged aqueous mixture obtained from (iv) exhibits a Cu:Zn:Al:Zr:Si molar ratio in the ranges of (40-65):(10-25):(15-40):(0.2-10):(0.1-5), preferably (45-62):(13-23):(18-35):(0.5-5):(0.3-4.5), more preferably (50-59):(15-21):(22-30):(1-3):(0.8-4), more preferably (55-56):(17-19):(25-26):(1.4-1.6):(1.2-3.6).

[0109] 17. The process of any one of the preceding embodiments, wherein the separation in (v) is achieved by filtration.

[0110] 18. The process is (vi) washing the solid obtained from (v); and / or, preferably, (vii) Drying the solid obtained from (v) or (vi) at a temperature in the range of preferably 80 to 150° C., preferably 90 to 140° C., more preferably 105 to 130° C., and even more preferably 115 to 125° C. 18. The process of any one of embodiments 1 to 17, further comprising:

[0111] 19. The process of embodiment 18, wherein the washing in (vi) is carried out with deionized water.

[0112] 20. The process according to embodiment 18 or 19, wherein the drying in (vii) is carried out for a time in the range of 1 hour to 48 hours, preferably in the range of 6 hours to 36 hours, more preferably in the range of 12 hours to 30 hours, and even more preferably in the range of 18 hours to 24 hours.

[0113] 21. The process is (ix) Calcining the solid obtained from (v), (vi) or (vii) at a temperature preferably in the range of 400 to 750° C., preferably in the range of 500 to 700° C., more preferably in the range of 550 to 650° C. 21. The process of any one of embodiments 1 to 20, further comprising:

[0114] 22. The process of embodiment 21, wherein the calcination in (ix) is carried out for a time in the range of 0.5 to 12 hours, preferably 1 to 6 hours, more preferably 1.5 to 2.5 hours.

[0115] 23. The process according to embodiment 21 or 22, wherein the calcination in (ix) is carried out in an atmosphere comprising oxygen, preferably in an atmosphere comprising air, more preferably the calcination in (ix) is carried out in air.

[0116] 24. A catalyst precursor comprising Cu, Zn, Al, Zr, Si and O according to any one of embodiments 31 to 39, preferably obtainable or obtained according to a process as described in any one of embodiments 1 to 23.

[0117] 25. A process for the preparation of a supported copper catalyst comprising Cu, Zn, Al, Zr, Si and O, preferably a supported copper catalyst according to any one of embodiments 40 to 46, wherein the catalyst comprises elemental copper, (1) Preparing a catalyst precursor comprising Cu, Zn, Al, Zr, Si, and O according to the process of any one of embodiments 21 to 23; (2) reducing the catalyst precursor obtained from (1) in a hydrogen-containing atmosphere to obtain a supported copper catalyst; A process including.

[0118] 26. The process according to embodiment 25, wherein the reduction of (2) is carried out at a temperature in the range of 150 to 350°C, preferably 170 to 300°C, more preferably 170 to 230°C.

[0119] 27. The process according to embodiment 25 or 26, wherein the atmosphere in (2) contains 0.25 to 80 vol.% H2, preferably 0.5 to 50 vol.% H2, more preferably 0.5 to 30 vol.% H2, even more preferably 1 to 10 vol.% H2, and even more preferably 2 to 5 vol.% H2.

[0120] 28. The process according to any one of embodiments 25 to 27, wherein the atmosphere in (2) contains 99.75 to 20% by volume of an inert gas, more preferably 99.5 to 50% by volume, even more preferably 99.5 to 70% by volume, even more preferably 99 to 90% by volume, and even more preferably 98 to 95% by volume.

[0121] 29. The process of embodiment 28, wherein the inert gas comprises one or more gases selected from the group consisting of noble gases, nitrogen gas, and methane, preferably selected from the group consisting of He, Ar, Ne, N2, and CH4, more preferably the inert gas comprises N2, and even more preferably the inert gas is N2.

[0122] 30. A supported copper catalyst comprising Cu, Zn, Al, Zr, Si and O according to any one of embodiments 40 to 46, preferably obtainable or obtained according to a process as described in any one of embodiments 25 to 29, wherein the catalyst comprises elemental copper.

[0123] 31. A catalyst precursor comprising Cu, Zn, Al, Zr, Si and O, preferably obtainable or obtained according to the process according to any one of embodiments 1 to 23, wherein the catalyst precursor exhibits a Zn:Si atomic ratio in the range of 5:1 to 27:1, preferably in the range of 5.5:1 to 25:1, more preferably in the range of 6:1 to 20:1, more preferably in the range of 6.5:1 to 15:1, more preferably in the range of 7:1 to 12:1, more preferably in the range of 7.5:1 to 10:1, more preferably in the range of 8:1 to 9:1.

[0124] 32. The catalyst precursor according to embodiment 31, wherein the catalyst precursor comprises one or more hydroxycarbonate mixed oxides comprising two or more of Cu, Zn and Al, preferably two or more of Cu, Zn, Al and Zr, more preferably the catalyst precursor comprises one or more hydroxycarbonate mixed oxides of Cu, Zn and Al, preferably Cu, Zn, Al and Zr.

[0125] 33. The catalyst precursor of embodiment 31 or 32, wherein the catalyst precursor comprises CuO.

[0126] 34. The catalyst precursor is Zr-modified Cu3Zn3Al2(OH) 16 CO3, preferably Zr modified Cu3Zn3Al2(OH) 16 Contains CO3·4H2O and Zr modified Cu3Zn3Al2(OH) 16 The 003 reflection in the X-ray diffraction diagram of CO3 is Cu3Zn3Al2(OH) 16 Compared to the X-ray diffraction pattern of CO3, it is shifted to higher °2θ values, and Zr-modified Cu3Zn3Al2(OH) 16 34. The catalyst precursor according to any one of embodiments 31 to 33, wherein the 003 reflection in the X-ray diffraction diagram of CO3 is located in the range of 11 to 13.5° 2θ, and the X-ray diffraction diagram is preferably determined according to Reference Example 2.

[0127] 35. The catalyst precursor according to embodiment 31, wherein the catalyst precursor comprises one or more oxides of Cu, Zn, Al, Zr, and Si, and the catalyst precursor preferably comprises one or more oxides selected from the group consisting of CuO, ZnO, ZnAl2O4, and CuAl2O4, more preferably the catalyst precursor comprises CuO, ZnO, and ZnAl2O4, or CuO, ZnO and CuAl2O4, or CuO, ZnO, ZnAl2O4 and CuAl2O4, preferably obtainable or obtained according to the process of embodiments 21-23.

[0128] 36. The catalyst precursor according to embodiment 35, wherein the catalyst precursor comprises CuO in an amount ranging from 50 to 70% by weight, calculated as the oxide CuO and based on the sum of the weights of the oxides of Cu, Zn, Al, Zr and Si calculated as CuO, ZnO, Al2O3, ZrO2 and SiO2 contained in the catalyst precursor, preferably the catalyst precursor comprises CuO in an amount ranging from 55 to 65% by weight, more preferably 58 to 62% by weight.

[0129] 37. The catalyst precursor of embodiment 35 or 36, wherein the catalyst precursor comprises SiO2.

[0130] 38. The catalyst precursor according to any one of embodiments 31 to 37, wherein the catalyst precursor exhibits a Cu:Zn:Al:Zr:Si molar ratio in the ranges of (40-65):(10-25):(15-40):(0.2-10):(0.1-5), preferably (45-62):(13-23):(18-35):(0.5-5):(0.3-4.5), more preferably (50-59):(15-21):(22-30):(1-4):(0.8-4), more preferably (55-56):(17-19):(25-26):(1.4-3):(1.2-3.6).

[0131] 39. The catalyst precursor according to any one of embodiments 31 to 38, wherein 95 to 100% by weight, more preferably 97 to 100% by weight, even more preferably 98 to 100% by weight, more preferably 99 to 100% by weight, even more preferably 99.5 to 100% by weight, and even more preferably 99.9 to 100% by weight of the catalyst precursor is composed of Cu, Zn, Al, Zr, Si, and O.

[0132] 40. A supported copper catalyst comprising Cu, Zn, Al, Zr, Si and O, preferably obtainable or obtained according to the process of embodiments 25 to 29, wherein the catalyst comprises elemental copper, and the catalyst exhibits a Zn:Si atomic ratio in the range of 5:1 to 27:1, preferably in the range of 5.5:1 to 25:1, more preferably in the range of 6:1 to 20:1, more preferably in the range of 6.5:1 to 15:1, more preferably in the range of 7:1 to 12:1, more preferably in the range of 7.5:1 to 10:1, more preferably in the range of 8:1 to 9:1.

[0133] 41. The supported copper catalyst of embodiment 40, wherein the supported copper catalyst comprises one or more oxides of Zn, Al, Zr, and Si, and the supported copper catalyst preferably comprises one or more oxides selected from the group consisting of ZnO, ZnAl2O4, and CuAl2O4, and more preferably the supported copper catalyst comprises ZnO and ZnAl2O4, or ZnO and CuAl2O4, or ZnO, ZnAl2O4, and CuAl2O4.

[0134] 42. Supported copper catalyst is 130m 2 / g or less, and preferably 60 to 130 m 2 42. The supported copper catalyst of embodiment 40 or 41, exhibiting a BET surface area in the range of 1.0 to 1.0 nm / g, the BET surface area being determined according to Reference Example 1.

[0135] 43. Supported copper catalyst is 5-15m 2 / g, preferably 10 to 13 m 2 / g, 43. The supported copper catalyst according to any one of embodiments 40 to 42, wherein the copper surface area is determined according to Reference Example 3.

[0136] 44. The supported copper catalyst of any one of embodiments 40-43, wherein the supported copper catalyst comprises SiO2.

[0137] 45. The supported copper catalyst according to any one of embodiments 40 to 44, wherein the supported copper catalyst exhibits a Cu:Zn:Al:Zr:Si molar ratio in the ranges of (40-65):(10-25):(15-40):(0.2-10):(0.1-5), preferably (45-62):(13-23):(18-35):(0.5-5):(0.3-4.5), more preferably (50-59):(15-21):(22-30):(1-4):(0.8-4), more preferably (55-56):(17-19):(25-26):(1.4-3):(1.2-3.6).

[0138] 46. ​​The supported copper catalyst according to any one of embodiments 40 to 45, wherein 95 to 100% by weight, preferably 97 to 100% by weight, more preferably 98 to 100% by weight, even more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight, and more preferably 99.9 to 100% by weight, of the supported copper catalyst is composed of Cu, Zn, Al, Zr, Si, and O.

[0139] 47. The supported copper catalyst of any one of embodiments 40 to 46, which is a shaped body having a height H and a three-pronged cross section with rounded tips and rounded corners.

[0140] 48. The supported copper catalyst of embodiment 47, wherein the tip base b of the trifurcated cross section having rounded tips and rounded corners is in the range of 2.00 to 2.60 mm, preferably in the range of 2.10 to 2.50 mm, more preferably in the range of 2.20 to 2.40 mm, and even more preferably in the range of 2.25 to 2.35 mm.

[0141] 49. The supported copper catalyst of embodiment 47 or 48, wherein the tip height i of the trifurcated cross section having rounded tips and rounded corners is in the range of 2.55 to 3.15 mm, preferably in the range of 2.65 to 3.05 mm, more preferably in the range of 2.75 to 2.95 mm, and even more preferably in the range of 2.80 to 2.90 mm.

[0142] 50. The supported copper catalyst of any one of embodiments 47 to 49, wherein the height h of the trifurcated cross section having rounded tips and rounded corners is in the range of 5.40 to 6.00 mm, preferably in the range of 5.50 to 5.90 mm, more preferably in the range of 5.60 to 5.80 mm, and even more preferably in the range of 5.65 to 5.75 mm.

[0143] 51. The supported copper catalyst according to any one of embodiments 47 to 50, wherein the chord length k of the trifurcated cross section having rounded ends and rounded corners is in the range of 6.00 to 6.60 mm, preferably in the range of 6.10 to 6.50 mm, more preferably in the range of 6.20 to 6.40 mm, and even more preferably in the range of 6.25 to 6.35 mm.

[0144] 52. The supported copper catalyst of any one of embodiments 47 to 51, wherein the trifurcated cross section with rounded tips and rounded corners has an interior angle α in the range of 5 to 19°, preferably in the range of 8 to 16°, more preferably in the range of 10 to 14°, and even more preferably in the range of 11 to 13°.

[0145] 53. The supported copper catalyst of any one of embodiments 47 to 52, wherein each tip of the trifurcated cross section is, independently of the others, rounded by an arc of a circle having a radius in the range of 0.65 to 1.25 mm, preferably in the range of 0.75 to 1.15 mm, more preferably in the range of 0.85 to 1.05 mm, and even more preferably in the range of 0.90 to 1.00 mm.

[0146] 54. The supported copper catalyst of any one of embodiments 47 to 53, wherein the distances between the geometric center C of the trifurcated cross section and each tip of the trifurcated cross section are, independently of one another, in the range of 2.0 to 5.0 mm, preferably in the range of 2.7 to 4.3 mm, more preferably in the range of 3.2 to 3.8 mm, and even more preferably in the range of 3.4 to 3.6 mm.

[0147] 55. The supported copper catalyst of any one of embodiments 47 to 54, wherein the trifurcated cross section with rounded tips and rounded corners has an exterior angle β in the range of 125° to 155°, preferably in the range of 135° to 145°, more preferably in the range of 127° to 137°, and even more preferably in the range of 130° to 134°.

[0148] 56. The supported copper catalyst of any one of embodiments 47 to 55, wherein each corner of the trifurcated cross section is rounded, independently of the others, by an arc of a circle having a radius in the range of 0.65 to 1.25 mm, preferably in the range of 0.75 to 1.15 mm, more preferably in the range of 0.85 to 1.05 mm, and even more preferably in the range of 0.90 to 1.00 mm.

[0149] 57. The supported copper catalyst according to any one of embodiments 47 to 56, wherein the height H of the molded body is in the range of 3.0 to 11.0 mm, preferably in the range of 3.5 to 10.5 mm, more preferably in the range of 4.5 to 9.5 mm, even more preferably in the range of 5.5 to 8.5 mm, and still more preferably in the range of 6.5 to 7.5 mm.

[0150] 58. A method for converting a CO2-containing synthesis gas into methanol, comprising the steps of: (A) providing a supported copper catalyst according to any one of embodiments 30 or 40 or 46; (B) preparing a gas mixture comprising CO, H2, and CO2; (C) contacting the supported copper catalyst provided in (A) with the gas mixture prepared in (B) at a temperature in the range of 200 to 350°C, preferably in the range of 230 to 260°C. The method includes:

[0151] 59. The method of embodiment 58, wherein the contacting in (B) is carried out at a pressure in the range of 1 to 100 bara, preferably in the range of 40 to 85 bara, more preferably in the range of 70 to 82 bara, and even more preferably in the range of 74 to 81 bara.

[0152] 60. The method according to embodiment 58 or 59, wherein the gas mixture prepared in (B) contains 10 to 24% by volume, preferably 11 to 20% by volume, more preferably 12 to 19% by volume, and even more preferably 15 to 18% by volume of CO2.

[0153] 61. The method according to any one of embodiments 58 to 60, wherein the gas mixture prepared in (B) comprises 0.5 to 7 vol.%, preferably 0.8 to 4 vol.%, more preferably 1 to 2 vol.% CO.

[0154] 62. The method according to any one of embodiments 58 to 61, wherein the gas mixture prepared in (B) exhibits a CO2:CO molar ratio in the range of 2 to 20, preferably 3 to 17, more preferably 5 to 15, and even more preferably 7 to 13.

[0155] 63. The method according to any one of embodiments 58 to 62, wherein the gas mixture prepared in (B) contains 50 to 90% by volume H2, preferably 55 to 87% by volume, more preferably 60 to 85% by volume, and even more preferably 65 to 83% by volume.

[0156] 64. The method according to any one of embodiments 58 to 63, wherein the gas mixture prepared in (B) contains 0.1 to 40% by volume, preferably 0.3 to 30% by volume, more preferably 0.5 to 25% by volume, even more preferably 0.8 to 20% by volume, and even more preferably 1 to 15% by volume of an inert gas.

[0157] 65. The method of embodiment 64, wherein the inert gas comprises one or more gases selected from the group consisting of noble gases and nitrogen gases, preferably selected from the group consisting of He, Ar, Ne, CH4 and N2, more preferably selected from the group consisting of Ar, CH4, N2, even more preferably the inert gas comprises CH4 and N2, and even more preferably the inert gas is CH4 and N2.

[0158] 66. A process for converting synthesis gas to dimethyl ether, comprising the steps of: (A) mixing the supported copper catalyst of any one of embodiments 30 or 40-57 with an acidic co-catalyst; (B) preparing a gas mixture comprising CO, H2, and CO2; (C) contacting the catalyst mixture provided in (A) with the gas mixture prepared in (B) at a temperature in the range of 200-300°C, preferably 250-270°C. The method includes:

[0159] 67. The method of embodiment 66, wherein the contacting in (B) is carried out at a pressure in the range of 1 to 100 bara, preferably in the range of 50 to 85 bara, more preferably in the range of 60 to 75 bara.

[0160] 68. The method according to embodiment 66 or 67, wherein the gas mixture prepared in (B) contains CO2 in an amount of 25% by volume or less, preferably 2-15% by volume, more preferably 3-10% by volume, and even more preferably 4-6% by volume.

[0161] 69. The method according to any one of embodiments 66 to 68, wherein the gas mixture prepared in (B) comprises 2 to 30 vol.%, preferably 5 to 29 vol.%, more preferably 10 to 28 vol.%, even more preferably 20 to 27 vol.%, and even more preferably 24 to 26 vol.% CO.

[0162] 70. The method according to any one of embodiments 66 to 69, wherein the gas mixture prepared in (B) exhibits a CO2:CO molar ratio of less than or equal to 5, preferably in the range of 0.05 to 2, more preferably in the range of 0.05 to 1, more preferably in the range of 0.1 to 0.5, and even more preferably in the range of 0.15 to 0.25.

[0163] 71. The method according to any one of embodiments 66 to 70, wherein the gas mixture prepared in (B) comprises 30 to 70 vol.%, preferably 40 to 65 vol.%, more preferably 50 to 60 vol.% H2.

[0164] 72. The method according to any one of embodiments 66 to 71, wherein the gas mixture prepared in (B) comprises 1 to 30% by volume, preferably 5 to 25% by volume, more preferably 10 to 20% by volume of an inert gas.

[0165] 73. The method of embodiment 72, wherein the inert gas comprises one or more gases selected from the group consisting of noble gases and nitrogen gases, preferably selected from the group consisting of He, Ar, Ne, CH4 and N2, more preferably the inert gas comprises CH4 and N2, even more preferably the inert gas is N2.

[0166] 74. Use of the supported copper catalyst according to any one of embodiments 30 or 40 to 57 as a reverse water-gas shift catalyst in the reforming of methanol, conversion of CO2-containing synthesis gas to methanol, reforming of dimethyl ether, and conversion of synthesis gas to dimethyl ether.

[0167] The present invention is further illustrated by the following Reference Examples, Examples and Comparative Examples. EXAMPLES

[0168] Samples were synthesised in stirred reaction vessels with full control of temperature, pH and solution inputs.

[0169] Reference Example 1. Determination of BET specific surface area The BET specific surface area was determined by nitrogen physisorption at 77 K according to the method disclosed in DIN 66131.

[0170] Reference Example 2: Powder X-ray diffraction and crystallinity determination Powder X-ray diffraction (PXRD) data were collected using a diffractometer (D8 Advance Series II, Bruker AXS GmbH) equipped with a LYNXEYE detector operated with a copper anode X-ray tube operated at 40 kV and 40 mA. The geometry was Bragg-Brentano and air scattering was reduced using an air scattering shield.

[0171] Calculation of crystallinity: The crystallinity of the samples was determined using the software DIFFRAC.EVA provided by Bruker AXS GmbH, Karlsruhe, according to the method described in the user manual, page 121. Default parameters for the calculation were used.

[0172] Calculation of phase composition: The phase composition was calculated on the raw data using the modeling software DIFFRAC.TOPAS provided by Bruker AXS GmbH (User Manual for DIFFRAC.TOPAS Version 6, 2017, Bruker AXS GmbH, Karlsruhe). Using the identified crystal structures of the phases, the instrumental parameters and the crystal sizes of the individual phases, a diffraction pattern was simulated. This was fitted to the data in addition to a function to model the background intensity.

[0173] Data collection: Samples were homogenized in a mortar and subsequently pressed into a standard flat sample holder provided by Bruker AXS GmbH for Bragg-Brentano geometry data collection. A flat surface was obtained by compressing and flattening the sample powder with a glass plate. Data were collected from the angle range 2-70°2θ with a step size of 0.02°2θ and the variable divergence slit was set at an angle of 0.1°. The crystalline content indicates the intensity of the crystalline signal relative to the total divergence intensity.

[0174] Reference Example 3: Determination of Cu surface area The Cu surface area was determined by the pulse method at 25° C. using N 2 O according to the method disclosed in EP 0 202 824 A.

[0175] Reference Example 4: Overview of prepared catalysts

[0176] [Table 1]

[0177] Example I: Preparation of supported Cu catalyst containing CuO / ZnO / Al2O3 / ZrO2 / SiO2, where SiO2 source is added into the precipitation reactor before charging Demineralized water (1000 g) was charged into the reaction vessel and brought to the target temperature (15-45 °C). To the demineralized water, an appropriate amount of natron water glass (1-60 g of an aqueous solution with 26 wt% Si calculated as SiO2) was added. The pH was adjusted to 9 and the co-precipitation was started. Under continuous stirring, an acid metal nitrate solution of Cu, Zn, Al and Zr (3,100 g, density 1.4 kg / l, composition see Table 1) was charged. In parallel, a basic aqueous solution of NaOH (2 M) mixed with Na2CO3 (0.3 M) (11,000 g) was added to maintain the pH value at 9. During the whole co-precipitation process, the pH and temperature were kept constant. After the complete charging of the solution, the resulting suspension was aged at 50 °C for 2 h under stirring. Afterwards, the suspension was filtered and the residual solid (700-800 g) was washed. The washed solid was dried overnight at 120 °C to finally obtain the catalyst precursor. The precursor was calcined under synthetic air (21 vol.% O2 / 79 vol.% N2) at 600° C. The resulting metal oxide powder was mixed with a graphitic binder and then compressed into tablets.

[0178] Example II: Preparation of supported Cu catalysts containing CuO / ZnO / Al2O3 / ZrO2 / SiO2 with SiO2 source added during aging Demineralized water (1000 g) was charged into the reaction vessel and brought to the target temperature (15-45 °C). The pH was adjusted to 9 and the co-precipitation was started. Under continuous stirring, an acidic metal nitrate solution of Cu, Zn, Al and Zr (3100 g, density 1.4 kg / l, composition see Table 1) was charged. In parallel, a basic aqueous solution of NaOH (2 M) mixed with Na2CO3 (0.3 M) (11,000 g) was added to maintain the pH value at 9. During the whole co-precipitation process, the pH and temperature were kept constant. After the complete charging of the solution, the resulting suspension was aged at 50 °C for 2 h under stirring. After aging for 1 h, an appropriate amount of natron water glass (1-60 g of an aqueous solution with 26 wt% Si calculated as SiO2) was added. After that, the suspension was filtered and the residual solid (700-800 g) was washed. The washed solid was dried overnight at 120 °C to finally obtain the catalyst precursor. The precursor was calcined under synthetic air (21 vol.% O2 / 79 vol.% N2) at 600° C. The resulting metal oxide powder was mixed with a graphitic binder and then compressed into tablets.

[0179] Example III: Catalytic testing in methanol synthesis from CO, CO and H The catalyst was first activated in a reducing atmosphere (5% H2 in Ar) at temperatures up to 250 °C. Once activation was complete, the pressure was increased to 80 bara and the test protocol started. The CO2-rich syngas tested consisted of 15 vol.% CO2, 2 vol.% CO, 73 vol.% H2, and the remainder N2, and was run for 6000–12000 h. -1 The H2 and CO2 feed streams were applied as make-up gases, and a CO content of 2 vol.% was chosen to simulate a process in which CO accumulates during the recycle due to the contribution of the reverse water-gas shift as a side reaction (see Eq. 3).

[0180] A rapid aging step (36 hour dwell) was included between the reference points set at 100 and 200 hours time on stream (TOS). This was done at 260°C and GHSV of 12,000 hours. -1was defined as being stoichiometrically rich in CO2 (30% by volume) in H2 (60% by volume), the balance being N2. Reference points after rapid ageing experiments were important to monitor the deactivation and especially the stability of the catalysts used. The catalysts were tested as sieve fractions of 400-500 microns.

[0181] Table 2 shows the relative space-time yield (STY) values ​​corresponding to the ZnO:SiO2 weight ratio and the difference in activity (%) before and after rapid ageing. Negative values ​​correspond to deactivation and positive values ​​to activation. Additionally, the N2O surface area is given (measurement according to EP 0 202 824 A, pulse method at 25 °C).

[0182] [Table 2]

[0183] As can be seen from the results shown in Table 2, the catalyst according to the present invention thus has a specific Zn to Si atomic ratio and exhibits very good space-time yields and relatively low activity decay.

[0184] Example IV: Catalytic testing in the direct synthesis of dimethyl ether from CO, CO and H The catalyst from Example 16 was applied in a one-step DME synthesis. The catalyst was mixed with an acidic cocatalyst (zeolitic catalyst according to EP 3727681 A1) for the dehydration of MeOH to DME. The activation protocol was the same as in Example III. The experiment was carried out at 63 bara, temperatures between 220 and 280 °C, and with CO rich synthesis gas (50 vol.% H2, 25 vol.% CO, 5 vol.% CO2, balance N2) at GHSV of 3000 h. -1 was supplied.

[0185] The results of the catalyst test are shown in Figures 4A and 4B. As can be seen from Figure 4A, the catalyst according to Example 16 showed a high CO conversion rate, slightly below 90%. After the process started, the CO conversion rate increased continuously during the process, and increased to about 92%.

[0186] As is evident from FIG. 4B, the catalyst according to Example 16 exhibited high selectivity to dimethyl ether. In particular, the selectivity to dimethyl ether was about 63% immediately after the start of the process, and increased slightly to about 64%. Furthermore, the selectivity to CO2 was only about 27% immediately after the start of the process, but then decreased to 26%. Meanwhile, the selectivity to MeOH was about 8% immediately after the start of the process, but then increased to about 10%. Overall, the catalyst was active over a long TOS and improved the selectivity to DME.

[0187] In summary, the catalyst according to Example 16 was found to exhibit very good performance, as shown by the stable conversion of CO and CO2, and the stable selectivity to dimethyl ether, CO2 and MeOH. Thus, the catalyst according to Example 16 is an improved catalyst, and it has been shown to exhibit good test results, especially under the severe conditions of temperature in the range of 220-280°C and pressure of 63 bara. It has also been shown that the catalyst according to Example 16 can withstand high partial pressures of CO2 and H2O. Thus, the catalyst according to the present invention is applicable to hydrogenation reactions of CO2 or CO2-rich synthesis gas, where high partial pressures of CO2 are part of the reactor feed (see Equations 2 and 3) or H2O is particularly concentrated as a by-product (see Equation 4).

[0188] Example V: Evaluation of pressure drop of tablets and compacts CFD simulations were carried out to evaluate the effect of two different compact geometries on the back pressure.

[0189] Tablets with a diameter of 6 mm and a height of 4 mm were used in the simulation as a shape representative of the prior art, and represent compacts that can be prepared by mixing metal oxide powders with a graphitic binder and then compressing them into tablets.

[0190] For the shape according to the invention, a molded body having a three-pronged cross section with rounded ends and rounded corners was used for the simulation, which could be prepared by mixing the metal oxide powder according to the invention with a graphite binder and molding it into a molded body.

[0191] Catalytic tests were carried out on tablets as well as compacts by CFD simulation.

[0192] The pressure drop Δp (Pa / m) and the relative pressure drop were calculated as follows: Δp=(p in -p out ) / H, and Relative Δp=Δp / Δp ref。

[0193] The pressure drop for the tablet was found to be 1 and for the compact it was 0.55.

[0194] As a result, it was found that the molded body allows for a significantly higher gas hourly space velocity at the same level of back pressure.

[0195] Cited Prior Art - Wu et al.Catalysis Today 1998,vol.45,p.215-220 - U.S. Patent No. 6,048,820 - European Patent Application Publication No. 2857095A1 - International Publication No. 2020 / 212681A1 Brochure - European Patent Application Publication No. 3727681A1

Claims

1. 1. A supported copper catalyst comprising Cu, Zn, Al, Zr, Si, and O, comprising elemental copper and exhibiting a Zn:Si atomic ratio in the range of 5:1 to 27:1, （１） (i) preparing a first aqueous solution S1 containing one or more copper-containing compounds, one or more zinc-containing compounds, one or more aluminum-containing compounds, and one or more zirconium-containing compounds, and having a pH in the range of 0 to 5; (ii) preparing a second aqueous solution S2, the pH of which is adjusted to a value in the range of 8.5 to 12; (iii) preparing an aqueous mixture M containing a solid suspended in water, comprising: adding S1 to S2 under stirring, wherein during said adding, the pH of the aqueous mixture M resulting from said adding is maintained in the range of 8 to 10; (iv) aging the aqueous mixture M obtained from (iii) for a time ranging from 1 hour to 12 hours; and (v) separating the solids from the aqueous mixture obtained from (iv). Preparing a catalyst precursor comprising Cu, Zn, Al, Zr, Si and O by a method comprising: one or more silicon-containing compounds are added for the preparation of S2 according to (ii), or one or more silicon-containing compounds are added to M during the aging of M according to (iv), or one or more silicon-containing compounds are added for the preparation of S2 according to (ii) and one or more silicon-containing compounds are added to said mixture M during the aging of M according to (iv); (2) reducing the catalyst precursor obtained from (1) in a hydrogen-containing atmosphere to obtain the supported copper catalyst; A supported copper catalyst obtainable by a process comprising:

2. 10. The supported copper catalyst of claim 1, comprising oxides of one or more of Zn, Al, Zr, and Si.

3. 2. The supported copper catalyst of claim 1, exhibiting a Cu:Zn:Al:Zr:Si molar ratio in the ranges of (50-59):(15-21):(22-30):(1-3):(0.8-4).

4. 1. A catalyst precursor comprising Cu, Zn, Al, Zr, Si, and O, and exhibiting a Zn:Si atomic ratio in the range of 5:1 to 27:1, (i) preparing a first aqueous solution S1 containing one or more copper-containing compounds, one or more zinc-containing compounds, one or more aluminum-containing compounds, and one or more zirconium-containing compounds, and having a pH in the range of 0 to 5; (ii) preparing a second aqueous solution S2, the pH of which is adjusted to a value in the range of 8.5 to 12; (iii) preparing an aqueous mixture M containing a solid suspended in water, comprising: adding S1 to S2 under stirring, wherein during said adding, the pH of the aqueous mixture M resulting from said adding is maintained in the range of 8 to 10; (iv) aging the aqueous mixture M obtained from (iii) for a time ranging from 1 hour to 12 hours; and (v) separating the solids from the aqueous mixture obtained from (iv). Including, A catalyst precursor obtainable by a process in which one or more silicon-containing compounds are added for the preparation of S2 according to (ii), or one or more silicon-containing compounds are added to M during the aging of M according to (iv), or one or more silicon-containing compounds are added for the preparation of S2 according to (ii) and one or more silicon-containing compounds are added to said mixture M during the aging of M according to (iv).

5. or comprising one or more hydroxycarbonate mixed oxides containing two or more of Cu, Zn and Al; 5. The catalyst precursor of claim 4, comprising oxides of one or more of Cu, Zn, Al, Zr, and Si.

6. The catalyst precursor is Zr-modified Cu ３ Zn ３ Al ２ (OH) １６ CO ３ The Zr-modified Cu ３ Zn ３ Al ２ (OH) １６ CO ３ The 003 reflection in the X-ray diffraction diagram of Cu ３ Zn ３ Al ２ (OH) １６ CO ３ The X-ray diffraction pattern of the Zr-modified Cu is shifted to a higher 2θ value compared to that of the Zr-modified Cu. ３ Zn ３ Al ２ (OH) １６ CO ３ 5. The catalyst precursor of claim 4, wherein the 003 reflection in the X-ray diffraction diagram of

7. 5. The catalyst precursor of claim 4, exhibiting a molar ratio of Cu:Zn:Al:Zr:Si in the ranges of (50-59):(15-21):(22-30):(1-3):(0.8-4).

8. (i) preparing a first aqueous solution S1 containing one or more copper-containing compounds, one or more zinc-containing compounds, one or more aluminum-containing compounds, and one or more zirconium-containing compounds, and having a pH in the range of 0 to 5; (ii) preparing a second aqueous solution S2, the pH of which is adjusted to a value ranging from 8.5 to 12; (iii) preparing an aqueous mixture M containing a solid suspended in water, comprising: charging S1 into S2 under stirring, wherein during said charging, the pH of the aqueous mixture M resulting from said charging is maintained in the range of 8 to 10; (iv) aging the aqueous mixture M obtained from (iii) for a time ranging from 1 hour to 12 hours; and (v) separating the solids from the aqueous mixture obtained from (iv).

1. A method for preparing a catalyst precursor comprising Cu, Zn, Al, Zr, Si and O, comprising: A method in which one or more silicon-containing compounds are added for the preparation of S2 according to (ii), or one or more silicon-containing compounds are added to M during the aging of M according to (iv), or one or more silicon-containing compounds are added for the preparation of S2 according to (ii) and one or more silicon-containing compounds are added to the mixture M during the aging of M according to (iv).

9. 9. The method of claim 8, wherein the one or more silicon-containing compounds comprise sodium waterglass.

10. moreover, (vi) washing the solid obtained from (v); and / or (vii) drying the solid obtained from (v) or (vi); and / or (ix) calcining the solid obtained from (v), (vi) or (vii). The method of claim 8, comprising:

11. 9. The method of claim 8, wherein in (iii), the pH of the aqueous mixture M is maintained in the pH range by metering a third aqueous solution S3 into the aqueous mixture M, the pH of S3 being in the range of 11 to 14.

12. 1. A method for preparing a supported copper catalyst comprising Cu, Zn, Al, Zr, Si, and O, said catalyst comprising elemental copper, said method comprising: (1) preparing a catalyst precursor comprising Cu, Zn, Al, Zr, Si, and O according to the method of claim 10; (2) reducing the catalyst precursor obtained from (1) in a hydrogen-containing atmosphere to obtain the supported copper catalyst; A method comprising:

13. CO ２ 1. A method for converting a contained synthesis gas into methanol, comprising: (A) providing a supported copper catalyst according to claim 1; (B) CO, H ２ and CO ２ preparing a gas mixture comprising: (C) contacting the supported copper catalyst provided in (A) with the gas mixture prepared in (B) at a temperature in the range of 200 to 350°C. A method comprising:

14. 1. A process for converting synthesis gas to dimethyl ether, comprising: (A) mixing the supported copper catalyst of claim 1 with an acidic co-catalyst; (B) CO, H ２ and CO ２ preparing a gas mixture comprising: (C) contacting the catalyst mixture provided in (A) with the gas mixture prepared in (B) at a temperature in the range of 200 to 300°C. A method comprising:

15. Methanol reforming, CO ２ 10. Use of the supported copper catalyst of claim 1 as a reverse water-gas shift catalyst in the conversion of synthesis gas containing compounds to methanol, in the reforming of dimethyl ether, and in the conversion of synthesis gas to dimethyl ether.

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