Cleaning of supply gas containing CO2

Abstract

The present invention relates to a method for washing a CO2-rich gas feed in the presence of a hydrogen-rich feed, particularly for removing sulfur-containing impurities and, if necessary, oxygen.

Description

Technical Field

[0001] Technical Field The present invention relates to a method for cleaning a CO2-rich gas feed for removing sulfur-containing impurities and, optionally, oxygen (O2).

Background Art

[0002] Background Carbon dioxide (CO2) is commercially available in various grades. Typically, "food grade" or "beverage grade" CO2 has a purity of 99.9%. However, in processes involving catalytic conversion of CO2 to other chemical products (e.g., power-to-X), impurities such as sulfur-containing impurities and oxygen in the CO2 stream can poison the synthesis catalyst, even when present at a concentration as low as 0.00001% (100 ppbV). Although it is rare for oxygen (O2) to actually inhibit the catalyst, when present at high concentrations, e.g., 100 ppm or more, it can cause structural damage to the catalyst due to its ability to oxidize the catalyst material, leading to mechanical degradation and a decrease in catalyst activity.

[0003] It has been found that certain CO2 sources, despite being of high purity, require further purification to avoid poisoning or decomposition of downstream synthesis catalysts.

[0004] Sulfur compounds are well-known as catalyst poisons and react with the active substances on the catalyst to deactivate it. In some catalysts, oxygen (O2) is also an important substance that causes catalyst decomposition. For example, copper-based methanol catalysts are susceptible to oxidation by oxygen, so when high concentrations of oxygen are present in the feed gas CO2 (or H2) to a methanol plant, it is necessary to remove it upstream of the methanol catalyst.

[0005] Catalyst / absorbent systems developed to remove sulfur impurities from CO2 have been found to be sensitive to relatively high oxygen concentrations, and solutions have been developed to remove O2 before the CO2 gas enters the sulfur removal system.

[0006] CO2 flow purification systems and methods are known, for example, in EP2457636, CN112999843, US2007028764, US200702877, US2022333015 and CN112957872. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] EP2457636 [Patent Document 2] CN112999843 [Patent Document 3] US2007028764 [Patent Document 4] US200702877 [Patent Document 5] US2022333015 [Patent Document 6] CN112957872 [Overview of the project] [Problems that the invention aims to solve]

[0008] overview The inventors found that sulfur removal from the CO2 feed is necessary and can be achieved by adsorption onto a metal-enhanced guard material after the addition of 2% H2, resulting in a sulfur content in the CO2 stream of <10 ppbV (less than 10 ppbV). They also found that oxygen in the CO2 feed can affect the sulfur treatment capacity and mechanical integrity of the guard material.

[0009] Therefore, a first embodiment of the present invention relates to a method for washing a CO2-rich gas feed containing at least 80% by mass of CO2 and one or more sulfur-containing impurities, the method comprising the following steps: The step of passing a CO2-rich gas supply together with a hydrogen-rich supply through a guard material, adsorbing one or more sulfur-containing compounds onto the guard material, and providing a cleaned CO2-rich gas flow.

[0010] A method for producing a synthesis gas flow is also provided, which includes the method described above and further includes: - To provide at least a portion of the cleaned CO2-rich gas stream from the above method; - To provide a second hydrogen-rich feedstock, optionally obtained from the electrolysis process of water, in one or more electrolytic devices; - Reacting a portion of the washed CO2-rich gas flow with the second hydrogen-rich feed to provide at least one synthesis gas flow.

[0011] A method for producing a synthetic fuel stream is also provided. The method includes the method described above and further includes the step of converting the at least one synthesis gas stream into at least one synthetic fuel stream, preferably a methanol (MeOH) stream, a dimethyl ether (DME) stream, or a synthetic fuel stream, the synthetic fuel may be aviation fuel, gasoline, diesel fuel, or similar.

[0012] Additional aspects are shown in the following description, drawings, and claims. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 shows a simplified layout of one embodiment of the method of the present invention. [Figure 2] Figure 2 shows the layout for producing the synthesis gas flow. [Figure 3] Figure 3 shows another layout of the CO2 gas purification method. [Figure 4]Figure 4 shows the data of Example II.

Mode for Carrying Out the Invention

[0014] Detailed Description Unless otherwise specified, the percentage of gas content is expressed in volume ratio as %(percent), ppm (one part per million), or ppb (one part per billion). All feeds are preheated as required. Unless otherwise specified, the concentration is shown on a dry basis. That is, the existing moisture is not considered.

[0015] The washed CO2 stream is defined as the outlet stream from the method for CO2 washing, and at least 95% of the total amount of sulfur-containing impurities in the feed has been removed, or the total amount of sulfur-containing impurities in the washed CO2 stream is less than 500 ppb (one part per billion by volume), preferably less than 100 ppb, and most preferably less than 50 ppb.

[0016] The total sulfur content in the washed CO2 stream should be understood as a sulfur-equivalent value. That is, 100 ppb of SO2 corresponds to 100 ppb of sulfur, while 100 ppb of CS2 corresponds to 200 ppb of sulfur.

[0017] Similarly, the washed CO2 stream as the outlet stream from the method for CO2 washing is defined such that at least 95% of the oxygen in the feed has been removed, or the O2 concentration in the washed CO2 stream is less than 200 ppm, preferably less than 100 ppm, and most preferably less than 50 ppm.

[0018] The term "syngas" is used as a reference to synthesis gas, which is a mixture of gases containing hydrogen, carbon monoxide, carbon dioxide, and usually water vapor or methane. It is called synthesis gas / syngas because it serves as the feed for downstream catalytic synthesis to obtain the desired product. In some applications, the feed gas downstream of the aforementioned purification process can be mixed with hydrogen and used as synthesis gas (e.g., methanol synthesis). In other applications, the purified gas needs to be mixed with hydrogen and optionally water vapor, and then converted in a reverse water-gas shift reactor (RWGS) or a combination of an RWGS and a methane reactor to form the final synthesis gas for the synthesis of the final product.

[0019] The proposed solution ensures that feed gases for downstream conversion to synthesis gas, and for the synthesis of chemicals such as MeOH, DME, FT (Fischer Tropsch) synthetic fuels, and TIGAS-based gasoline, do not pose a problem in terms of sulfur and oxygen inhibition of downstream synthesis catalysts. This enables long-term operation and ensures the catalyst life expected for industrial catalysts.

[0020] Therefore, as a first aspect, we provide a method for cleaning CO2-rich gas feedstocks.

[0021] The CO2-rich gas feed supplied to this method contains at least 90% by mass of CO2, for example, at least 95% by mass of CO2, at least 99.0% by mass of CO2, preferably at least 99.5% by mass of CO2, and more preferably at least 99.9% by mass of CO2. Therefore, the CO2-rich gas feed is already of high purity before the method of the present invention.

[0022] Preferably, the CO2 supply is derived from renewable resources: for example, - Combustion or gasification of lignocellulose-based biomass, such as wood products, algae, grass, forestry waste and / or agricultural residues; - Incineration or gasification of municipal waste, in particular its organic parts, where municipal waste is defined as supply materials including materials from articles discarded by the public, such as mixed municipal waste as defined in EU Directive 2018 / 2001 (RED II) Annex IX Part A; - Nitrogen-rich renewable raw materials, such as fertilizers or sewage sludge, through microbial conversion; - Fermentation of carbohydrates (sugars) such as corn, sugarcane, and beets, which are rich in supply logistics.

[0023] CO2-rich gas sources can also be obtained from direct air recovery processes, metallurgical processes, cement production, or fossil fuel combustion.

[0024] In most of the above gas streams, the CO2 concentration is usually too low for further chemical treatment; therefore, a concentration step is required to increase the CO2 concentration to the desired value mentioned above.

[0025] The CO2-rich gas feed contains one or more sulfur-containing impurities. The one or more sulfur-containing impurities in the CO2-rich gas feed source are selected from organic sulfur compounds, such as thiols, sulfides, disulfides, sulfones, sulfoxides, thioketones, CS2, COS, SO3, SO2, and H2S, preferably H2S and SO2, most preferably SO2. The total SO2 content in the CO2-rich gas feed source is 0.1 to 50 ppmV of SO2, for example 0.2 to 10 ppm of SO2, for example 1 to 10 ppm of SO2, for example 0.5 to 5 ppm of SO2, for example 1 to 5 ppm of SO2.

[0026] CO2-rich gas feeds may also contain water. However, high concentrations of water can limit / inhibit the adsorption of sulfur compounds onto the guard material, and limiting the water concentration allows for more efficient operation of the guard system. Therefore, the total H2O content in a feed combining CO2-rich gas feeds and hydrogen-rich feeds should be 10% by volume or less, preferably 5.0% by volume or less, more preferably 1.0% by volume or less, for example, about 0.5% by volume or less.

[0027] CO2-rich gas feeds may contain oxygen (O2) in certain cases. Because oxygen can contaminate, toxicize, or degrade downstream catalysts and guard materials, oxygen in CO2-rich gas feeds should normally be reduced or removed. The total O2 content in CO2-rich gas feeds is typically between 50 and 10,000 ppm, e.g., 50 to 5,000 ppm, e.g., 100 to 3,000 ppm.

[0028] Generally, this method includes the following steps: passing a CO2-rich gas feed through a guard material together with a hydrogen-rich feed, adsorbing one or more sulfur-containing compounds onto the guard material, and providing a cleaned CO2-rich gas stream.

[0029] In one embodiment, the CO2-rich gas feed further contains oxygen (O2), and the method includes an additional step: - A step of passing a CO2-rich gas feed together with the hydrogen-rich feed through a catalyst active in the hydrogenation of oxygen, thereby reducing the oxygen in the CO2 / H2 gas mixture and providing a first CO2-rich gas flow. The following step involves passing the CO2-rich gas supply through a guard material for adsorbing one or more sulfur-containing impurities, thereby providing a cleaned CO2-rich gas stream.

[0030] The CO2-rich gas feed to be purified can first be mixed with a hydrogen-rich feed, which functions as a reducing agent for one or more sulfur-containing impurities and, optionally, oxygen in the CO2-rich gas feed. The hydrogen-rich feed to this method contains at least 90% by mass of hydrogen, for example, at least 95% by mass of hydrogen, for example, at least 98% by mass of hydrogen.

[0031] In one embodiment, hydrogen is added appropriately such that the total H2 content in the mixed feed of the CO2-rich gas feed and the hydrogen-rich feed after mixing of the feeds is 0.2 to 10 volume percent of H2, for example, 0.5 to 3 volume percent of H2. The advantage of this embodiment is that undesirable side reactions such as methanol production can be limited by controlling the addition of H2. The amount of hydrogen added should always be sufficient to generate excess H2 in the product gas discharged from the guard material.

[0032] In one embodiment, in a combined feed of a CO2-rich gas feed and a hydrogen-rich feed, hydrogen is appropriately added after mixing the feeds such that the molar ratio H2:O2 exceeds 2, and the H2 content in the purified CO2 discharged from the CO2 washing system is 0.2 to 10 volume%, for example, 0.5 to 3 volume%. The advantage of this embodiment is that by controlling the addition of H2, it is possible to maintain a sufficient excess amount of H2 to ensure high-level hydrogenation of oxygen and sulfur impurities while limiting undesirable side reactions such as methanol production. Furthermore, in this embodiment, the smallest possible reactor and apparatus size can be achieved in order to minimize the total gas flow rate.

[0033] In another embodiment of the present invention, an amount of hydrogen corresponding to the feed composition for downstream processes for the production of synthesis gas, methanol, synthetic fuels, and other chemical products is added to the CO2-rich gas feed. For example, in methanol production, the feed composition for the methanol process is approximately 12% by mass (w / w) of H2 and 88% by mass of CO2. This corresponds to a ratio of 3 moles of H2 per mole of CO2. An advantage of this embodiment is that H2 and CO2 can be mixed and preferably compressed before CO2 washing. The CO2 washing method can be placed downstream of the final compression step or between intermediate compression steps, and the optimal location is selected considering cost, water concentration, the risk of carbonate formation on the guard material, and the risk of formation of undesirable by-products such as water and methanol. Another advantage of this embodiment is that O2 present in the H2-rich feed is also hydrogenated. H2 obtained by the electrolysis of water may contain varying amounts of O2 depending on the operating state of the electrolyte.

[0034] The one or more sulfur-containing compounds adsorbed on the guard material are usually selected from COS, SO2, and H2S, and are preferably SO2. The guard material is appropriately active in the absorption of SO2 and H2S, and is preferably a Cu-Zn-Al guard material. In the presence of H2, the guard material can catalytically reduce SO2 in a CO2-rich feed gas to produce H2S, which is adsorbed much more efficiently on the guard than SO2. The guard can also react the oxygen content in the CO2 feed gas with hydrogen to form water.

[0035] This method provides a cleaned CO2-rich gas flow. This cleaned CO2-rich flow typically includes the following: -Sulfur less than 500 ppb, preferably less than 100 ppb, more preferably less than 50 ppb, more preferably less than 25 ppb O2 with less than -200 ppmV, less than 100 ppmV, and less than 50 ppmV. The guard material used in the method of the present invention is appropriately placed in a reaction vessel, which is configured to receive a CO2-rich gas feed and a hydrogen-rich feed in a mixed state as needed.

[0036] The guard material preferably has a chemical composition of 25-60% by mass (w / w%) Cu, 15-70% by mass Zn, and optionally 2-10% by mass Al. Trace amounts of K and C may be included. The elements exist in either a reduced or oxidized state.

[0037] The CO2 washing method described above is typically operated in a pressure range of 1 to 100 bar, preferably 1 to 50 bar, depending on the pressure of the supply logistics and the pressure of the downstream conversion process.

[0038] To achieve an optimal balance between high catalyst / adsorption efficiency and a low tendency for undesirable side reactions such as carbonate formation and water / methanol production, CO2 washing methods are typically operated in a temperature range of 120-250°C. The pressure is also typically in the range of 1-90 bar.

[0039] In one embodiment, more than 95% of one or more sulfur-containing impurities are retained by the guard material, or the total concentration of sulfur-containing impurities in the washed CO2-rich gas stream is <500 ppb (less than 500 ppb), for example, <100 ppb, for example, <50 ppb.

[0040] As described above, the washed CO2-rich gas stream is sufficiently pure, and catalyst poisoning in downstream processes is significantly reduced. Therefore, the present invention provides a method for producing a synthesis gas stream, the method including the method described above, and further including: - To provide at least a portion of the cleaned CO2-rich gas stream obtained by the method described herein; -Optionally, to provide a second hydrogen-rich feed obtained from the electrolysis process of water in one or more electrolytic devices; - A portion of the washed CO2-rich gas feed is reacted with the second hydrogen-rich feed to provide at least one synthesis gas stream.

[0041] In this method, the step of reacting a portion of the washed CO2-rich gas feed with a second hydrogen-rich feed to provide at least one synthesis gas stream can be carried out in the presence of a catalyst active in the reverse water-gas shift reaction.

[0042] An integrated process is also possible, in which CO2 removal, synthesis gas production, and subsequent downstream synthesis are carried out in sequence. Thus, a method is provided for producing a synthetic fuel flow, the method comprising providing at least one synthesis gas flow as described herein, and further comprising the step of converting the at least one synthesis gas flow into at least one synthetic fuel flow, which is preferably a methanol flow, a DME flow, or a synthetic fuel flow, preferably the synthetic fuel being aviation fuel, gasoline, or diesel fuel. In one embodiment, the method for converting the at least one synthesis gas flow into at least one synthetic fuel flow is the Fischer-Tropsch process for providing a synthetic fuel flow. In another embodiment, the method for converting the at least one synthesis gas flow into at least one synthetic fuel flow is the TIGAS process for providing a synthetic fuel flow.

[0043] Specific Embodiments Figure 1 shows a simplified layout of one embodiment of the process of the present invention. A CO2-rich gas feed 1 is mixed with a hydrogen-rich feed 2 and passes through a guard material 10 in a reactor vessel 100. Sulfur-containing compounds are adsorbed on the guard material 10, and the washed CO2-rich gas stream 50 is discharged.

[0044] Figure 2 shows the production layout of the synthesis gas flow. The reactor vessel 100, CO2-rich gas feed 1, hydrogen-rich feed 2, and the washed CO2-rich gas flow 50 are the same as in Figure 1. Subsequently, the second hydrogen-rich feed 202 reacts with the washed CO2-rich flow feed 50 in the synthesis gas section 300 to provide at least one synthesis gas flow 301.

[0045] Figure 3 shows an example of a layout for a CO2 gas purification method. A CO2 gas feed (1) containing O2 and one or more sulfur impurities is mixed with a certain amount of hydrogen-rich gas (2). The mixed gas is sent to a compressor (5) where the pressure increases. The high-pressure feed gas (6) is then preheated in a heat exchanger (7), and the heated feed gas (9) is sent to an oxygen-hydrogenation reactor (11), where an oxygen-hydrogenation catalyst (12) is installed to hydrogenate O2 to H2O. A substantially O2-free CO2 gas stream (17) is cooled in a heat exchanger (18) and adjusted so that the feed gas (20) to the desulfurization reactor (22) is at an optimal temperature. A guard material (10) is installed in the reactor to remove sulfur impurities. The off-gas from the desulfurization reactor (26) has been substantially free of oxygen and sulfur impurities and can be further processed into synthesis gas and other products. [Examples]

[0046] example A test was conducted to evaluate the efficiency of SO2 removal from guard material under isothermal conditions in a laboratory fixed-bed reactor. The fixed-bed reactor was placed in an electrically heated oven and heated to a predetermined operating temperature. Two internal thermocouples measured the inlet and outlet temperatures of the catalyst layer. The oven was equipped with an external thermocouple to control the temperature zones within the oven. These zones were controlled by the readings of the internal thermocouples to achieve isothermal reaction conditions within the fixed bed.

[0047] The guard material is placed on a grid inside the reactor, which is made of stainless steel coated with SilcoNert 2000®, and the reactor is positioned in the center of the electric oven. The feed gas is mixed from gas cylinders using a mass flow controller to control the supply rate of each gas. This includes nitrogen (N2), hydrogen (H2), carbon dioxide (CO2), and sulfur dioxide (SO2 in CH4) at 15 or 100 ppmV in methane. Liquid water is supplied by pump and, after passing through an evaporator, is mixed with the feed gas upstream of the fixed-bed reactor.

[0048] The guard material used is a co-precipitated Cu / ZnO / alumina-based guard material. In individual tests where the guard material can be separated into multiple fractions (beds), the total weight of the guard material and the number of fractions / beds are indicated. Each fraction is usually of uniform size. The guard material was crushed and sieved before charging to obtain the optimal particle size in the experimental reactor, and adjusted to a particle size range of 600 μm to 1000 μm from the original particle size. Before measuring the SO2 removal rate in the feed gas, the guard material was reduced in a 2% H2 atmosphere in N2 under conditions of 220°C and 3 barg.

[0049] Table 1 lists the different tests conducted with SO2 in the CO2 feed gas, and the outlet analyses listed are the results after continuous SO2 addition for 200 hours.

[0050] [Table 1]

[0051] Sulfur supply and exhaust gas concentrations were measured using an Agilent 7890AGC system equipped with an OI 5380 pulsed flame photometric detector (PFPD), except for experiments 1 and 2. Experiments 1 and 2 used Agilent 8355,S and S chemiluminescence detectors with a high detection limit of 100 ppbV. For experiments #5b and 6, since the detection limit for SO2 was 50 ppbV, the outlet analysis value for SO2 was estimated based on the sulfur balance. These results are shown in italics.

[0052] Example (II) The O2 hydrogenation activity of Topsoe's O2Xtract® hydrogenation catalyst, containing Pd and Pt as active ingredients, was evaluated. Hydrogenation activity was measured in a CO2-rich feed gas containing 2.5 vol% H2, 2,000 ppm O2, and 0 or 10 ppm SO2. The catalyst space velocity was 180,000 Nm. 3 / h / m 3 The temperature was varied within the range of 50 to 350°C. The O2 concentration was measured at the catalyst inlet and outlet using a dedicated O2 / CO2 sensor, and the O2 hydrogenation conversion rate was calculated based on these concentrations. The conversion rate as a function of catalyst temperature is shown in Figure 4. While it is clear that this hydrogenation catalyst is highly active in O2 hydrogenation, it has also been shown that the catalytic activity is significantly inhibited by the presence of SO2. To operate the O2 hydrogenation catalyst without the risk of sulfur poisoning, the temperature should be higher than 200°C, preferably closer to 250-350°C or higher.

[0053] Example III In the process layout shown in Figure 3, after CO2 gas purification, the CO2 feed gas is mixed with an amount of H2 equivalent to 3 moles of H2 per mole of CO2, resulting in a mixed gas suitable for methanol production in the downstream synthesis plant.

[0054] The CO2 feed gas contains 1 volume% O2 and 5 ppm SO2. The CO2 feed gas is mixed with the total H2 feed, compressed to 90 barg, and preheated to 185°C in a dedicated heat exchanger. However, the heat exchanger 7 in Figure 3 is divided into a feed gas preheater equipped with its own heat source such as steam or electricity, and a feed / exhaust heat exchanger connecting the low-temperature side of heat exchanger 7 to the high-temperature end of heat exchanger 18.

[0055] The feed gas at 185°C is preheated to 300°C in the feed / exhaust heat exchanger by heat exchange with the high-temperature gas from the outlet of the O2 hydrogenation reactor 11. At this temperature, the O2 hydrogenation catalyst is active and is not poisoned by SO2 in the mixed gas. The O2 hydrogenation reaction is a strongly exothermic reaction, raising the temperature by 35°C to 335°C, so the temperature rise in the feed / exhaust heat exchanger is adequately compensated for. To control the reactor inlet temperature, 15-20% of the high-temperature gas from the O2 hydrogenation reactor (17) is bypassed to the feed / exhaust heat exchanger. The high-temperature gas from the reactor is cooled to 195°C in the feed / exhaust heat exchanger and mixed with the bypassed high-temperature gas, resulting in a mixed gas temperature of 220°C to the downstream guard material (10), which falls within the optimal temperature range for this method. SO2 is hydrogenated to H2S and captured at the Cu and Zn sites of the guard material. The process gas, thus purified, is sent to the methanol synthesis plant at the optimal temperature for the methanol converter.

[0056] Alternatively, instead of the aforementioned high-temperature gas bypass, there is also the option of bypassing a portion of the low-temperature gas to the feed / exhaust heat exchanger.

[0057] Typically, supply / exhaust heat exchangers are designed with a minimum temperature difference of 10–20°C to provide an economical and efficient heat exchanger. If the CO2 feed contains 0.2 vol% O2, the adiabatic temperature rise of the O2 hydrogenation reactor in this example is 7°C, which falls below the usual design standard. To reduce the design temperature difference, the heat exchange area can be increased, or a small auxiliary heater can be installed to compensate for the required temperature difference of 3–13°C. In principle, it is also possible to increase the heat output by adding O2 to the CO2 gas to accelerate the hydrogenation reaction, but this option can be costly in terms of H2 consumption. Furthermore, the excess water produced reduces the capacity and conversion efficiency of the guard material in the downstream methanol plant.

[0058] An alternative solution involves performing O2 hydrogenation and sulfur removal before adding total hydrogen. Specifically, 3 vol% hydrogen is added, sufficient to hydrogenate both O2 and sulfur. Because the gas volume is reduced, the adiabatic temperature rise is 21°C, and the supply / exhaust heat exchanger functions efficiently without modification.

[0059] In carbon dioxide-rich and hydrogen-rich flows with high concentrations of oxygen, it is beneficial to remove the generated water vapor in guard materials and upstream of the synthesis plant. Water removal can be achieved by cooling the gas mixture to below the dew point of water, allowing the water vapor to condense and be separated and recovered as a liquid.

[0060] The present invention has been described with reference to several aspects and drawings. However, those skilled in the art can select and combine various aspects within the scope of the invention as defined by the appended claims. All references herein are incorporated by reference.

Claims

1. CO ２ - A method for cleaning a rich gas supply (1), wherein the CO ２ - Rich gas supply (1) contains at least 80% by mass of CO ２ and containing one or more sulfur-containing impurities, the next step is: - The aforementioned CO ２ - The rich gas supply (1) is passed through the guard material (10) together with the hydrogen-rich supply (2), and one or more sulfur-containing compounds are adsorbed onto the guard material (10), and the washed CO ２ - Steps to provide a rich gas flow (50), The method, including the method described above.

2. The above-mentioned CO ２ -rich gas supply (1) contains at least 90% by mass of CO ２ , for example, at least 95.0% by mass of CO ２ , preferably at least 99% by mass of CO ２ , more preferably at least 99.5% by mass of CO ２ The method according to claim 1, which comprises

3. The aforementioned CO ２ - The one or more sulfur-containing impurities in the rich gas supply (1) are organic sulfur compounds such as thiols, sulfides, disulfides, sulfones, sulfoxides and thioketones, COS, SO2 ３ SO ２ and H ２ S, preferably H ２ S and SO ２ Therefore, more preferably SO ２ The method according to claim 1 or 2, selected from the above.

4. The guard material (10) is SO ２ From H ２ Reduction to S, and H ２ The method according to any one of claims 1 to 3, wherein the material is active in adsorbing S and is preferably a Cu-Zn-Al guard material.

5. The guard material (10) is placed inside the reaction vessel (100), and the reaction vessel (100) is the CO ２ The method according to any one of claims 1 to 4, wherein the rich gas supply (1) and the hydrogen-rich supply (2) are optionally arranged to be received in a mixed state.

6. The aforementioned sulfur-containing impurity is SO ２ The CO ２ - SO in rich gas supply (1) ２ The concentration is 0.1 to 50 ppm SO ２ For example, 1 to 10 ppm SO ２ For example, 1-5 ppm SO ２ The method according to any one of claims 1 to 5.

7. The aforementioned CO ２ - Rich gas feed (1) and / or hydrogen-rich feed (2) further contains oxygen (O ２ ) and the following additional steps: -CO ２ - The rich gas feed (1) is passed together with the hydrogen-rich feed (2) through a catalyst (12) that is active in the hydrogenation of oxygen, CO ２ / H ２ The oxygen in the gas mixture is reduced to form the first oxygen-depleted CO2 ２ - Step of providing a rich gas flow, Includes, Subsequently, the first oxygen-depleted CO2 ２ The rich gas supply is passed through a guard material (10) to adsorb one or more sulfur-containing impurities, and the washed CO ２ - The method according to any one of claims 1 to 6, which provides a rich gas flow.

8. The aforementioned CO ２ - O in rich gas supply (1) ２ The total content is 50 to 10,000 ppm of O ２ For example, 50 to 5000 ppm O ２ For example, 100-3000 ppm O ２ The method according to any one of claims 1 to 7.

9. More than 95% of O is present on the catalyst that is active in the hydrogenation of oxygen. ２ The CO2 is converted, or the washed CO2 is converted. ２ - O in a rich gas stream ２ The method according to any one of claims 1 to 8, wherein the total concentration of is <200 ppm, for example <100 ppm, for example <50 ppm.

10. The aforementioned CO ２ The method according to any one of claims 1 to 9, wherein the step of passing a -rich gas feed (1) and a hydrogen-rich feed (2) through a catalyst (12) active in the hydrogenation reaction is carried out at a temperature in the range of 200 to 400°C and a pressure in the range of 1 to 90 bar.

11. The aforementioned CO ２ - In a combined feed of the rich gas feed (1) and the hydrogen-rich feed (2), after mixing the feeds, and this mixture is subjected to any O ２ H ２ The total content of H is 0.2 to 10% by volume. ２ For example, 0.5 to 3 volume percent of H ２ The method according to any one of claims 1 to 10.

12. The aforementioned CO ２ - In a combined feed of rich gas feed (1) and hydrogen-rich feed (2), after mixing of the feeds, H ２ The total content is CO ２ 2 to 5 moles of H per mole ２ A method according to any one of claims 1 to 9, which corresponds to the ratio of .

13. The aforementioned CO ２ - In a combined feed of rich gas feed (1) and hydrogen-rich feed (2), after mixing of the feeds, H ２ The method according to any one of claims 1 to 12, wherein the total content of O is 10% by volume or less, preferably 5.0% by volume or less, preferably 1.0% by volume or less, for example, about 0.5% by volume.

14. The aforementioned CO ２ The method according to any one of claims 1 to 13, wherein the step of passing a -rich gas feed (1) and a hydrogen-rich feed (2) through a guard material (10) is carried out at a temperature in the range of 120 to 250°C and a pressure in the range of 1 to 90 bar.

15. More than 95% of one or more sulfur-containing impurities are retained in the guard material, or the CO2 is washed away. ２ - The method according to any one of claims 1 to 14, wherein the total concentration of sulfur-containing impurities in the rich gas stream is <500 ppb, for example <100 ppb, for example <50 ppb.

16. The aforementioned CO ２ The supply (1) is a renewable resource derived from, for example, renewable resources from the following, according to any one of claims 1 to 15: - Combustion or gasification of lignocellulose-based biomass, such as wood products, algae, grass, forestry waste and / or agricultural residues; - Incineration or gasification of municipal waste, in particular its organic parts, where municipal waste is defined as supply materials including materials from articles discarded by the public, such as mixed municipal waste as defined in Annex IX Part A of EU Directive 2018 / 2001 (RED II); - Nitrogen-rich renewable raw materials, such as fertilizers or sewage sludge, through microbial conversion; - Fermentation of hydrocarbon (sugar)-rich supply logistics from corn, sugarcane, beets, etc.

17. A method for producing a synthesis gas flow, comprising the method according to any one of claims 1 to 16, further - The cleaned CO from the method according to any one of claims 1 to 16 ２ - A step of providing at least a portion of the rich gas flow (50); -Optionally, a step of providing a second hydrogen-rich feed (202) optionally obtained from the electrolysis of water in one or more electrolytic devices; - The washed CO ２ - A step of reacting a portion of the rich flow feed (50) with the second hydrogen-rich feed (202) to provide at least one synthesis gas flow (301). The method, including the method described above.

18. The washed CO ２ The method according to claim 17, wherein the step of reacting a portion of the rich flow feed (50) with the second hydrogen-rich feed (202) to provide at least one synthesis gas flow (301) is carried out in the presence of a catalyst active in the reverse water-gas shift reaction.

19. A method for producing a synthetic fuel flow, comprising the method according to any one of claims 17 to 18, further comprising the step of converting the at least one synthetic gas flow (301) into at least one synthetic fuel flow, preferably a MeOH flow, a synthetic fuel flow, or a TIGAS flow.

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