Integrated Fischer-Tropsch process

Abstract

The present disclosure generally relates to a method for carrying out an integrated Fischer-Tropsch process, the method comprising providing a first feed stream comprising H2 and CO2, contacting a reverse water gas shift catalyst with the first feed stream at a first temperature and a first pressure in the range of 200 to 900 °C to carry out a reverse water gas shift reaction and providing a first product stream comprising CO and H2, the first product stream having a lower CO2 concentration and a higher CO concentration than the first feed stream, and contacting a Fischer-Tropsch catalyst with a second feed stream comprising at least a portion of the H2 and CO of the first product stream at a second temperature and a second pressure to provide a second product stream comprising C5+ hydrocarbons.

Description

Cross - reference to related applications

[0001] This application claims the benefit of priority of International Patent Application PCT / CN2022 / 102724 filed on June 30, 2022, the entire content of which is incorporated herein by reference.

Technical Field

[0002] The present disclosure generally relates to a reverse water - gas shift catalyst, a method for manufacturing the same, and a method for carrying out a reverse water - gas shift reaction. The present disclosure also relates to integrating a method for carrying out a reverse water - gas shift reaction with a method for carrying out a Fischer - Tropsch reaction.

Background Art

[0003] The reverse water - gas shift reaction (rWGS) is an advantageous route for obtaining carbon monoxide from carbon dioxide for further chemical processing. rWGS converts carbon dioxide and hydrogen into carbon monoxide and water, as shown in Equation (1).

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[0004] This can be used, for example, to change the CO:H2 ratio of a gas mixture for further processing. The carbon monoxide and hydrogen thus formed are valuable feedstocks for many chemical processes, such as the well - known Fischer - Tropsch (FT) process shown in Equation (2).

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[0005] However, the rWGS reaction is not advantageous in all situations. For example, a competing reaction is the Sabatier reaction (Equation (3)), which advantageously reduces the carbon monoxide yield for methane formation, which is not an active feedstock for FT.

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[0006] The strong exothermic Sabatier reaction is thermodynamically more favorable than the endothermic rWGS reaction at lower reaction temperatures. Therefore, minimizing methanation during rWGS, especially at low temperatures, can be an important challenge.

[0007] Similarly, the carbon monoxide product from rWGS can be hydrogenated to methane, as shown in Equation (4).

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[0008] The hydrogenation of carbon monoxide to methane is also an exothermic reaction and is thus also favorable at lower temperatures. The stoichiometry of the reaction requires at least a 3:1 hydrogen to carbon monoxide ratio. This means that performing the rWGS reaction with a large excess of hydrogen to drive the equilibrium towards carbon monoxide (see Equation (1)) is not always ideal as it risks hydrogenating the carbon monoxide product to form methane.

[0009] In combination with Equations (3) and (4), further unwanted side reactions can occur. These side reactions can potentially form unwanted carbon deposits on the surface of the catalyst used to promote rWGS. Examples of these carbon-forming side reactions are shown in Equations (5), (6), and (7). All three of these reactions are endothermic and, like the rWGS reaction, are favorable at higher temperatures.

[0010]

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[0011] Therefore, since the carbon formation side reactions (Equations (5)-(7)) are also endothermic and are more favorable at higher temperatures, operation at a higher temperature to favor the desired carbon monoxide product can have a profound impact on catalyst life through carbon deposition.

[0012] Considering that multiple reactions and competing thermodynamics are at play, a new integration with the Fischer-Tropsch process is still needed in the art. SUMMARY OF THE INVENTION

[0013] In one aspect, the present disclosure provides a method for implementing an integrated Fischer-Tropsch process, the method comprising: forming a first feed stream comprising H2 and CO2; contacting a reverse water gas shift catalyst with the first feed stream at a first temperature and a first pressure in the range of 200 to 900 °C to perform a reverse water gas shift reaction to form a first product stream comprising CO and H2, wherein the first product stream has a lower CO2 concentration and a higher CO concentration than the first feed stream; contacting a Fischer-Tropsch catalyst with a second feed stream comprising H2 and at least a portion of the CO of the first product stream at a second temperature and a second pressure to form a second product stream comprising C5+ hydrocarbons. BRIEF DESCRIPTION OF THE DRAWINGS

[0014]

Figure 1

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[0015] As described above, the reverse water-gas shift reaction reacts carbon dioxide with hydrogen to produce carbon monoxide and water, and is useful for providing a feedstock containing carbon monoxide and hydrogen, often referred to as "synthesis gas", for use in processes such as the Fischer-Tropsch process. However, the Sabatier reaction, carbon monoxide methanation, and carbon formation side reactions can interfere with the rWGS reaction. The Sabatier reaction and CO methanation are exothermic and favored at low temperatures, while the rWGS and carbon formation side reactions are endothermic and favored at high temperatures. Accordingly, there remains a need to integrate the reverse water-gas shift process with the Fischer-Tropsch process.

[0016] In one aspect, the present disclosure provides a method for implementing an integrated Fischer-Tropsch process, the method comprising providing a first feed stream comprising H2 and CO2, contacting a reverse water-gas shift catalyst with the first feed stream at a first temperature and a first pressure in the range of 200-900 °C to effect a reverse water-gas shift reaction and provide a first product stream comprising CO and H2, the first product stream having a lower CO2 concentration and a higher CO concentration than the first feed stream, and contacting a Fischer-Tropsch catalyst with at least a portion of the H2 and CO of the first product stream at a second temperature and a second pressure to provide a second product stream comprising C5+ hydrocarbons.

[0017] The methods described herein include contacting a reverse water gas shift catalyst with a first feed stream described herein. The reverse water gas shift catalyst is not particularly limited, and one skilled in the art can select a suitable catalyst. For example, one skilled in the art can select a catalyst as described in Daza et al., "CO2 Conversion by Reverse Water Gas Shift Catalysts: Comparison of Catalysts, Mechanisms, and the Results They Bring for CO2 Conversion to Liquid Fuels", RSC Adv., 2016, 6, 49675-49691, Zhu et al., "Catalytic Reduction of CO2 to CO by the Reverse Water Gas Shift Reaction: Recent Advances in the Design of Active and Selective Supported Metal Catalysts", Transaction of Tianjin University, 2020, 26, 172-187, and Chen et al., "Recent Advances in Supported Metal Catalysts and Oxide Catalysts for the Reverse Water Gas Shift Reaction", Front. Chem., 2020, 8, 709. These catalysts include rWGS active metals. For example, such active metals may be selected from copper, platinum, palladium, rhodium, rhenium, ruthenium, nickel, gold, and iridium, or combinations thereof.

[0018] Reverse water gas shift catalysts suitable for use in the methods described herein can be in various forms and are not particularly limited. For example, the reverse water gas shift catalyst can be a supported catalyst or an unsupported catalyst. The form of the catalyst is not particularly limited, but in various desirable embodiments, the reverse water gas shift catalyst is a supported catalyst, and the support includes at least one of titanium oxide, zirconium oxide, cerium oxide, aluminum oxide, silicon oxide, and zinc oxide. For example, in various embodiments, the support includes at least one of titanium oxide, zirconium oxide, cerium oxide, and aluminum oxide. In some embodiments of the disclosure described herein, the support is a titanium dioxide support. In some embodiments of the disclosure described herein, the support is a zirconium dioxide support. In some embodiments of the disclosure described herein, the support is a cerium dioxide support. In some embodiments of the disclosure described herein, the support is an aluminum dioxide support.

[0019] Those skilled in the art will understand that the reverse water gas shift catalysts of the present disclosure can be provided in many forms, depending in particular on the specific form of the reactor system in which they are used, for example, in a fixed bed or as a fluidized bed. The carrier of the reverse water gas shift catalyst can itself be provided as a separate body of material, for example, as porous particles, pellets, or shaped extrudates, on which a metal is provided to provide the reverse water gas shift catalyst. However, in other embodiments, the reverse water gas shift catalysts of the present disclosure can themselves be formed as a layer on a underlying substrate. The underlying substrate is not particularly limited. It can be formed, for example, from a metal or metal oxide and can itself be provided in many forms such as particles, pellets, shaped extrudates, or monoliths. Those skilled in the art will select a Fischer-Tropsch catalyst appropriate for a particular reactor system.

[0020] This method includes providing a first feed stream containing H2 and CO2, and contacting the first feed stream with the reverse water gas shift catalyst described herein at a first temperature and a first pressure in the range of 200 to 900 °C to carry out a reverse water gas shift reaction to provide a first product stream containing CO and H2, the first product stream having a lower CO2 concentration and a higher CO concentration than the first feed stream. An example of such a method is schematically shown in FIG. 1. In FIG. 1, method 100 includes performing a reverse water gas shift reaction by supplying a first feed stream 111 consisting of H2 and CO2, here to a first reaction zone, for example reactor 110. The reverse water gas shift catalyst 113 described herein contacts the feed stream 111 at a first temperature in the range of 200 to 900° C. and a first pressure to provide a first product stream 112 containing CO and H2. The first product stream has a lower concentration of CO2 and a higher concentration of CO than the first feed stream. The method of this aspect of the present disclosure also includes contacting a Fischer-Tropsch catalyst at a second temperature and a second pressure with a second feed stream containing H2 and at least a portion of the CO of the first product stream to provide a second product stream containing C5+ hydrocarbons. In method 100 of FIG. 1, at least a portion of the CO of the first product stream 112 is included in the second feed stream 121, which here is contacted with a Fischer-Tropsch catalyst 123 in a second reaction zone (for example, reactor 120). This provides a second product stream 122 containing C5+ hydrocarbons.

[0021] As used herein, "feed stream" is used to mean all the materials input into a method step, such as a reverse water gas shift or Fischer-Tropsch reaction, regardless of whether it is provided as a single physical stream or multiple physical streams, and regardless of whether it passes through a single inlet or multiple inlets. For example, the H2 and CO of the first feed stream can be provided to the reverse water gas shift catalyst in a single physical stream (e.g., a single pipe to reactor 110), or in multiple physical streams (e.g., separate inlets for CO and H2, or one inlet for fresh CO and H2 and another inlet for recycled CO and / or H2). Similarly, "product stream" is used to mean all the material output from a method step, such as a reverse water gas shift or Fischer-Tropsch reaction, regardless of whether it is provided as a single physical stream or multiple physical streams, and regardless of whether it passes through a single outlet or multiple outlets.

[0022] As described above, the first feed stream contains both H2 and CO2 (e.g., provided to the reaction zone in a single physical stream or multiple physical streams). In various embodiments described elsewhere herein, the molar ratio of H2 to CO2 in the first feed stream is at least 0.1:1, e.g., at least 0.5:1. In some embodiments, the molar ratio of H2 to CO2 in the first feed stream is at least 0.9:1, e.g., at least 1:1 or at least 1.5:1. In some embodiments, the molar ratio of H2 to CO2 in the first feed stream is at least 2:1, e.g., at least 2.5:1. In some embodiments, the molar ratio of H2 to CO2 in the first feed stream is 100:1 or less, e.g., 75:1 or less or 50:1 or less. In some embodiments, the molar ratio of H2 to CO2 in the first feed stream is 20:1 or less, e.g., 15:1 or less or 10:1 or less. For example, in some embodiments, the molar ratio of H2 to CO2 in the first feed stream is in the range of 0.5:1 to 10:1. One of ordinary skill in the art can, based on the disclosure herein, provide the desired ratio of H2:CO2 in the first feed stream that provides the desired conversion and selectivity, and excess H2, when consistent with the desired conversion and selectivity, is provided to flow through the system to provide a first product stream having the desired ratio of H2 to CO for downstream processes, e.g., the Fischer-Tropsch process.

[0023] Other gases may also be included in the first feed stream. For example, in some embodiments, the first feed stream further contains CO. In some embodiments of the present disclosure described elsewhere herein, the first feed stream further contains one or more inert gases. For example, in some embodiments, the first feed stream further contains nitrogen and / or methane.

[0024] The methods described herein include contacting an rWGS catalyst with a first feed stream to conduct an rWGS reaction. In particular, the inventors have determined that the rWGS catalysts described herein can provide desirably high CO selectivity. For example, in various embodiments of the present disclosure described herein, the reverse water gas shift reaction has a CO selectivity of at least 70%, e.g., at least 80%. In various embodiments, the reverse water gas shift reaction has a CO selectivity of at least 85%, e.g., or at least 90%. In various embodiments, the reverse water gas shift reaction has a CO selectivity of at least 95%, e.g., or at least 96%. As used herein, the “selectivity” of a given reaction product is the mole fraction of the relevant component of the feed (here, CO2) that is converted to the product (for “CO selectivity,” with respect to CO). The inventors have determined that the rWGS catalysts described herein can provide excellent selectivity to CO even when operating at a lower temperature than many conventional reverse water gas shift catalysts and despite the potential for competition by the Sabatier reaction and methanation of CO. For example, in some embodiments separately described herein, the reverse water gas shift reaction has a CO selectivity of at least 98%, e.g., or at least 99%.

[0025] In particular, even within a wide temperature range, e.g., in the range of 200 to 900 °C, the rWGS catalysts described herein can be operated to provide carbon monoxide with only a very small degree of methane formation. For example, in various embodiments of the present disclosure described herein, the reverse water gas shift reaction has a methane selectivity of 5% or less, e.g., 4% or less. For example, in some embodiments, the reverse water gas shift reaction has a methane selectivity of 2% or less, e.g., 1% or less. In some embodiments, the reverse water gas shift reaction has a methane selectivity of 0.5% or less, e.g., 0.2% or less.

[0026] The inventors have determined that the rWGS catalysts described herein can provide desirably high CO selectivity and desirably low methane selectivity at commercially relevant conversion rates. As used herein, "conversion rate" is the mole fraction of the relevant component feedstock that is reacted (to become the desired product or an undesired species). In various embodiments of the disclosure described herein, the reverse water gas shift reaction has a CO2 conversion of at least 5%, such as at least 10%, or at least 20%. For example, in some embodiments, the reverse water gas shift reaction has a CO2 conversion of at least 30%, such as at least 40%, or at least 50%, or at least 60%. In various embodiments of the disclosure described herein, the reverse water gas shift reaction has a CO2 conversion of 90% or less, such as 80% or less, or 70% or less. For example, in some embodiments, the reverse water gas shift reaction has a CO2 conversion of 65% or less, such as 60% or less. For example, in various embodiments separately described herein, the CO2 conversion is in the range of 10 - 90%, such as 10 - 80%, or 10 - 70%, or 10 - 60%, or 10 - 65%, or 20 - 90%, or 20 - 80%, or 20 - 70%, or 20 - 60%, or 20 - 65%, or 30 - 90%, or 30 - 80%, or 30 - 70%, or 30 - 60%, or 30 - 65%, or 40 - 90%, or 40 - 80%, or 40 - 70%, or 40 - 60%, or 40 - 65%. One of ordinary skill in the art will operate at a degree of conversion that provides the desired product, based on the disclosure herein. Of course, in other embodiments, such as when in a stacked bed or mixed bed system, the effective CO2 conversion can be even higher than that described herein.

[0027] Advantageously, the rWGS method described herein can be carried out at a temperature lower than the temperatures used in many conventional reverse water gas shift methods. As described above, the various methods of performing the rWGS reaction of the present disclosure can be carried out at a first temperature in the range of 200 to 900 °C. For example, in some embodiments, the reverse water gas shift reaction is carried out at a first temperature in the range of 200 to 850 °C, or 200 to 800 °C, or 200 to 750 °C, or 200 to 700 °C, or 200 to 650 °C, or 200 to 600 °C. In some embodiments of the present disclosure described herein, the method for carrying out the reverse water gas shift reaction is carried out at a first temperature in the range of 250 to 900 °C, for example, 250 to 850 °C, or 250 to 800 °C, or 250 to 750 °C, or 250 to 700 °C, or 250 to 650 °C, or 250 to 600 °C. In some embodiments of the present disclosure described herein, the method for carrying out the reverse water gas shift reaction is carried out at a first temperature in the range of 300 to 900 °C, for example, 300 to 850 °C, or 300 to 800 °C, or 300 to 750 °C, or 300 to 700 °C, or 300 to 650 °C, or 300 to 600 °C. In some embodiments of the present disclosure described herein, the method for carrying out the reverse water gas shift reaction is carried out at a first temperature in the range of 350 to 900 °C, for example, 350 to 850 °C, or 350 to 800 °C, or 350 to 750 °C, or 350 to 700 °C, or 350 to 650 °C, or 350 to 600 °C. In some embodiments, the method for carrying out the reverse water gas shift reaction is carried out at a first temperature in the range of 400 to 900 °C, for example, 400 to 850 °C, or 400 to 800 °C, or 400 to 750 °C, or 400 to 700 °C, or 400 to 650 °C, or 400 to 600 °C. In some embodiments, the method for carrying out the reverse water gas shift reaction is carried out at a first temperature in the range of 450 to 900 °C, for example, 450 to 850 °C, or 450 to 800 °C, or 450 to 750 °C, or 450 to 700 °C, or 450 to 650 °C, or 450 to 600 °C.In some embodiments, the method for performing the reverse water gas shift reaction is carried out at a first temperature in the range of 500 to 900 °C, for example, in the range of 500 to 850 °C, or 500 to 800 °C, or 500 to 750 °C, or 500 to 700 °C, or 500 to 650 °C, or 500 to 600 °C. In some embodiments, the method for performing the reverse water gas shift reaction is carried out at a first temperature in the range of 550 to 900 °C, for example, in the range of 550 to 850 °C, or 550 to 800 °C, or 550 to 750 °C, or 550 to 700 °C, or 550 to 650 °C, or 550 to 600 °C.

[0028] In some embodiments, the reverse water gas shift reaction is carried out at a first temperature in the range of 200 to 500 °C, for example, in the range of 200 to 450 °C, or 200 to 400 °C, or 200 to 350 °C, or 250 to 500 °C, or 250 to 450 °C, or 250 to 400 °C, or 250 to 350 °C. The inventors have noted that operation at these temperatures can provide lower energy requirements and easy integration with subsequent Fischer-Tropsch process steps.

[0029] Furthermore, the rWGS method described herein can be carried out at various pressures, as will be understood by those skilled in the art. In various embodiments of the present disclosure, the method for performing the reverse water gas shift reaction is carried out at a first pressure in the range of 1 to 100 barg. For example, the rWGS method is carried out at a first pressure in the range of 1 to 70 barg, or 1 to 50 barg, or 1 to 40 barg, or 1 to 35 barg, or 5 to 70 barg, or 5 to 50 barg, or 5 to 40 barg, or 5 to 35 barg, or 10 to 70 barg, 10 to 50 barg, or 10 to 40 barg, or 10 to 35 barg, or 20 to 70 barg, 20 to 50 barg, or 20 to 40 barg, or 20 to 35 barg, or 25 to 70 barg, 25 to 50 barg, or 25 to 40 barg, or 25 to 35 barg.

[0030] As will be understood by those skilled in the art, the rWGS method described herein can be carried out at various GHSVs (gas hourly space velocities). Therefore, the GHSV for carrying out the reverse water gas shift reaction is not particularly limited. For example, in some embodiments of the present disclosure, the method for carrying out the reverse water gas shift reaction is carried out at a GHSV in the range of 1,000 to 2,000,000 h-1. In various embodiments, the method for carrying out the reverse water gas shift reaction is 1,000 to 1,200,000 h-1, or 1,000 to 500,000 h-1, or 1,000 to 100,000 h-1, or 5,000 to 1,200,000 h-1, or 5,000 to 500,000 h-1, or 5,000 to 100,000 h-1, or 10,000 to 1,200,000 h-1, or 10,000 to 500,000 h-1, or 10,000 to 100,000 h-1 in terms of the GHSV range. In various embodiments of the present disclosure, the method for carrying out the reverse water gas shift reaction is 1,000 to 50,000 h-1, or 2,000 to 50,000 h-1, or 5,000 to 50,000 h-1, or 10,000 to 50,000, or 1,000 to 40,000 h-1, or 2,000 to 40,000 h-1, or 5,000 to 40,000 h-1, or 10,000 to 40,000 h-1, or 1,000 to 30,000 h-1, or 2,000 to 30,000 h-1, or 5,000 to 30,000 h-1, or 10,000 to 30,000 h-1 in terms of the GHSV range.

[0031] For example, it is typically desirable to activate the rWGS catalyst before contacting it with the first feed stream. Thus, in some embodiments of the disclosure described herein, the method includes activating the rWGS catalyst before contacting the catalyst with the feed stream. For example, in some embodiments, activating the catalyst includes contacting the catalyst with a reducing gas, such as a reducing stream containing hydrogen. In various embodiments of the disclosure, the reducing stream contains hydrogen in an amount of at least 25 mol%, such as at least 50 mol%, or 75 mol%, or 90 mol%. One of ordinary skill in the art will determine the appropriate conditions for reducing the activation of the rWGS catalyst. Thus, one of ordinary skill in the art will be able to select the appropriate temperature, pressure, and time for activating the rWGS catalyst. For example, in various embodiments, the activation of the rWGS catalyst is carried out at a temperature in the range of 200°C to 800°C. For example, in various embodiments, the activation of the rWGS catalyst is carried out at a temperature in the range of 250°C to 800°C, or 300°C to 800°C, or 200°C to 700°C, or 250°C to 800°C, or 300°C to 700°C. In some embodiments of the disclosure described herein, activating the rWGS catalyst provides an rWGS catalyst that is reduced by at least 10% (e.g., at least 25%, or at least 50% reduced).

[0032] The inventors have found that by contacting an rWGS catalyst as described herein with a first feed stream, a first product stream having advantageously high CO selectivity and low methane selectivity can be provided. The amount of CO in the first product stream can be further controlled by the rWGS reaction conditions as described above. However, generally, methods for performing an rWGS reaction as described herein provide a first product stream comprising H2 and CO, the first product stream having a lower concentration of CO2 and a higher concentration of CO than the first feed stream, to match the degree of conversion and selectivity described herein. For example, in various embodiments, the first product stream comprises up to 95 mol% CO2, or up to 90 mol% CO2. In some embodiments, the first product stream comprises up to 85 mol% CO2, or up to 80 mol% CO2. In other examples, the first product stream comprises up to 75 mol% or up to 70 mol% CO2.

[0033] It was determined that it may be desirable to carry out the process at a degree of conversion of. Further, the inventors have noted that it may be advantageous to carry out the downstream Fischer-Tropsch process using a relatively high level of inert material, and thus believe that it may be beneficial to pass a significant amount of CO2 through the Fischer-Tropsch process step. Thus, in various embodiments described herein separately, the first product stream comprises an amount of CO2 along with CO. In various embodiments, the first product stream comprises CO2 in the range of 5-95 mol%, such as 5-90 mol%, or 5-85 mol%, or 5-80 mol%, or 5-75 mol%, or 5-70 mol%, or 10-95 mol%, or 10-90 mol%, or 10-85 mol%, or 10-80 mol%, or 10-75 mol%, or 10-70 mol%, or 20-95 mol%, or 20-90 mol%, or 20-85 mol%, or 20-80 mol%, or 20-75 mol%, or 20-70 mol%, or 30-95 mol%, or 30-90 mol%, or 30-85 mol%, or 30-80 mol%, or 30-75 mol%, or 30-70 mol%.

[0034] Other gases may also be included in the first product stream. In some embodiments of the disclosure described herein, the first product stream further comprises one or more inert gases. These inert gases may be included from the first feed stream or provided from a source other than the first feed stream. For example, in some embodiments, the first product stream further comprises nitrogen and / or methane.

[0035] In particular, depending on the conversion rate, CO selectivity, relative amounts of H2 and CO2 in the first feed stream, and reaction conditions, the first product stream can contain H2 in various ratios in combination with CO. For example, in some embodiments, the H2:CO ratio in the first product stream is in the range of 0.1:1 to 100:1 (e.g., in the range of 0.1:1 to 50:1, or 0.1:1 to 25:1, or 0.1:1 to 10:1, or 0.1:1 to 5:1, or 1:1 to 100:1, or 1:1 to 50:1, or 1:1 to 25:1, or 1:1 to 10:1, or 1:1 to 5:1).

[0036] Those skilled in the art will understand that based on the methods described herein, the first product stream can contain H2, CO, and CO2, as well as other components in various amounts. The components of the first product stream can be separated and used for various purposes in an integrated process.

[0037] For example, in various embodiments of the present disclosure described herein, the method further includes separating a first product stream and recycling at least a portion (e.g., at least 5 mol%, at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, or at least 90 mol%) of one or more components of the first product stream to a first feed stream. For example, if the first product stream contains CO2, the method can include recycling at least a portion (e.g., at least 5 mol%, at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, or at least 90 mol%) of the CO2 in the first product stream to the first feed stream. The first product stream can also contain H2. In some embodiments, the method further includes recycling at least a portion (e.g., at least 5 mol%, at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, or at least 90 mol%) of the H2 in the first product stream to the first feed stream.

[0038] Such recycling is shown in method 100 of FIG. 1. Here, method 100 includes separating at least a portion (stream 114) of CO2 from the first product stream 112 and recycling it to the first feed stream 111. Similarly, method 100 includes separating at least a portion (stream 115) of H2 from the first product stream 112 and recycling it to the first product stream 111. Stream 115 is shown as entering the reactor 110 through an inlet different from the remainder of the first feed stream 111, but since it is part of the material introduced into the method steps, it is considered to be part of the first feed stream.

[0039] Furthermore, as described below, Fischer-Tropsch catalysts typically require activation by a reducing gas. As will be understood by those skilled in the art, different Fischer-Tropsch catalysts require different activation conditions (e.g., gas composition, temperature, pressure, time). For example, iron-based Fischer-Tropsch catalysts require activation by both H2 and CO, while cobalt-based Fischer-Tropsch catalysts require activation by H2 only. Thus, this activation can be carried out using H2 and CO or H2 only from the first product stream. Thus, in various embodiments described elsewhere herein, the method comprises separating at least a portion of H2 and CO (preferably in a ratio of at least 1:1 or at least 3:1) from the first product stream and contacting it with a Fischer-Tropsch catalyst to activate the Fischer-Tropsch catalyst. In various other embodiments described elsewhere herein, the method comprises separating at least a portion of H2 from the first product stream and contacting it with a Fischer-Tropsch catalyst to activate the Fischer-Tropsch catalyst. For example, in the method of FIG. 1, stream 125 separates H2 or H2 and CO and directs it to reactor 120. This separation need not be continuous; rather, it may be carried out for only as long as desired to supply the reducing gas to the Fischer-Tropsch catalyst for activation. Of course, as will be understood by those skilled in the art, other sources of H2 or CO may be used to supply the reducing gas to the Fischer-Tropsch catalyst for activation.

[0040] As shown above, water is a product of the reverse water gas shift reaction. Thus, the first product stream generally contains water. In many cases, it is desirable to reduce the amount of water fed to the Fischer-Tropsch process. Accordingly, in various embodiments described elsewhere herein, the method further includes removing at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the water from the first product stream. In the embodiment of FIG. 1, a water removal zone 116 is used to remove water and provide a water-containing stream 117. Those skilled in the art will understand that various methods can be used to remove water from the first product stream. For example, the first product stream can be contacted with a water scavenger to remove water therefrom. For example, a molecular sieve guard bed can be used to remove water from the first product stream, and the water can be recovered from the molecular sieve of the guard bed, for example, by heating and vacuum. In other embodiments, a knockout vessel can be used. However, the use of a knockout vessel may, in some cases, be able to sufficiently cool the first product stream such that it is desirably reheated for introduction into the Fischer-Tropsch process. The water removed from the first product stream can be used, for example, as a water supply for the electrolysis method described herein.

[0041] As described above, one competing reaction in the reverse water gas shift reaction is the Sabatier reaction that produces methane. In various embodiments, the reverse water gas shift methods described herein can be carried out without forming large amounts of methane, although in some embodiments some methane may be formed. Thus, in various embodiments of the methods described herein, the first product stream comprises one or more light hydrocarbons. For example, in some embodiments, the first product stream can comprise one or more of methane, ethane, propane, or combinations thereof. As would be understood by those skilled in the art, it may be desirable to operate the reverse water gas shift reaction to provide a greater amount of light hydrocarbons in the first product feed. For example, such light hydrocarbons can be inert in further processing of the first product stream and thus can be tolerated in higher amounts. Those skilled in the art will be able to select appropriate reaction conditions (e.g., temperature, pressure, first feed stream composition) to provide a first product stream containing methane in the desired amount. For example, in various embodiments described elsewhere herein, the first product stream comprises 20 mol% or less methane or 15 mol% or less methane. As described above, when it is desirable that the amount of methane in the first product stream be less, the rWGS catalysts of the present disclosure can provide very low methane selectivity. Thus, in various embodiments described elsewhere herein, the first product stream comprises 10 mol% or less methane. For example, in various embodiments, the first product stream comprises 5 mol% or less, or 1 mol% or less, or 0.5 mol% or less, or 0.1 mol% or less methane. Generally, light hydrocarbons (e.g., C1-C5 hydrocarbons) can be present in the product stream. For example, in various embodiments described elsewhere herein, the product stream comprises 20 mol% or less light hydrocarbons (e.g., 15 mol% or less, 10 mol% or less, 5 mol% or less, 1 mol% or less, 0.5 mol% or less, or 0.1 mol% or less light hydrocarbons).

[0042] These light hydrocarbons (e.g., C1-C5 hydrocarbons) can be separated and used for other purposes. For example, in various embodiments, the method further includes separating at least a portion of one or more light hydrocarbons from a first product stream to provide a light hydrocarbon stream. For example, in method 100 of FIG. 1, at least a portion of one or more light hydrocarbons is separated from the first product stream 112 to provide a light hydrocarbon stream 118. The light hydrocarbon stream can be used, for example, to provide other products, can be partially oxidized to form CO, can be steam reformed to provide hydrogen, and / or can be combusted to provide heat or other energy (e.g., electricity for electrolysis) for use in an integrated method or other process.

[0043] Of course, as will be understood by those skilled in the art, the light hydrocarbon stream can be used in other processes as well. For example, as will be understood by those skilled in the art, some rWGS catalysts can have reforming capabilities. Without being bound by theory, the inventors hypothesize that one explanation for the low methane production observed using the rWGS catalysts described herein is that methane is formed but is then immediately reformed to CO and H2. Thus, in some embodiments described herein, the light hydrocarbons in the process stream are recycled to the feed stream for the rWGS reaction.

[0044] As described above, the reverse water gas shift process can be provided at a wide variety of temperatures. In some cases, these temperatures may be relatively close to the temperature of a subsequent Fischer-Tropsch process (often 150 to 400 °C, for example, 200 to 350 °C, or other temperatures described below). In other cases, the reverse water gas shift process can be carried out at a temperature significantly higher than the temperature of the Fischer-Tropsch process. The inventors have noted that it may be desirable to provide heat exchange with a relatively hot first product stream to cool the first product stream to an appropriate temperature by the Fischer-Tropsch process and to provide heat elsewhere in the integrated process. For example, in various embodiments of the methods described elsewhere herein, the method further includes exchanging heat between at least a portion of the first product stream and at least a portion of the first feed stream, thereby cooling at least a portion of the first product stream and heating at least a portion of the first feed stream. An example of such a method is schematically shown in FIG. 2. In FIG. 2, method 200, first reactor 210, first feed stream 211, first product stream 212, reverse water gas shift catalyst 213, second reactor 220, second feed stream 221, second product stream 222, and Fischer-Tropsch catalyst 223 are generally as described above. Here, method 200 includes exchanging heat between at least a portion of the first product stream 212 and at least a portion of the first feed stream 211 in a first heat exchange zone 230, thereby cooling at least a portion of the first product stream 212 and heating at least a portion of the first feed stream 211. Those skilled in the art will understand that a wide variety of heat exchangers can be used for this purpose.

[0045] Of course, any excess heat in the first product stream can additionally or alternatively be used for other purposes. For example, in various embodiments, the method further includes exchanging heat between at least a portion of the first product stream and a steam generation zone, thereby cooling at least a portion of the first product stream and providing heat to the steam generation zone. This is shown in FIG. 2. Here, after heat exchange with the first feed stream 211, the first product stream 212 is directed to the steam generation zone 232, cooling the first product stream 212 and providing heat to the steam generation zone 232. Steam can be generated from the supplied heat, and electricity can be generated from the steam. For example, in the embodiment of FIG. 2, the electric current 264 is provided by generating electricity using the steam generated in the steam generation zone 232. Of course, as will be understood by those skilled in the art, the steam generated in the steam generation zone may be used in other ways. In various embodiments, the steam may be used to heat the first feed stream. For example, in the embodiment of FIG. 2, the steam stream 266 generated in the steam generation zone 232 is directed to the heat exchange zone 290 to heat the first feed stream 211.

[0046] As described above, at least a portion of the CO in the first product stream is included in the second feed stream for the reaction in the Fischer-Tropsch process. For example, in various embodiments described elsewhere herein, at least 25% of the CO in the first product stream, such as at least 50% of the CO in the first product stream, at least 75% of the CO, or at least 90% of the CO, is included in the second feed stream. Of course, as described above, a portion of the CO in the first product stream can be used for other purposes, such as for catalyst activation as described herein.

[0047] In some embodiments, substantially all of the CO in the second feed stream comes from the first product stream. However, in other embodiments, the CO can be provided to the second feed stream from a fossil-derived or other alternative source. For example, in various embodiments, the CO is provided to the second feed stream from a CO source other than the first product stream. In FIG. 2, a flow of CO 226a from an alternative source is included in the second feed stream 221. One of ordinary skill in the art will understand that the CO can be provided from various sources, such as gasification, reforming, or electrochemical CO2 reduction. Further, as described in more detail below, the CO can be recycled from the second product stream to the second feed stream; and / or provided by reaction of a light hydrocarbon stream, for example, by partial oxidation or reforming (e.g., steam reforming and / or autothermal reforming).

[0048] As described above, the second feed stream contains H2. In particular, the first product stream often contains, for example, unreacted H2 from the first feed stream. In various embodiments, the first product stream contains H2 and the second feed stream contains at least a portion of the H2 of the first product stream. For example, in various embodiments as described elsewhere herein, at least 25% of the H2 of the first product stream, such as at least 50% of the H2 of the first product stream, at least 75% of the H2, or at least 90% of the H2, is included in the second feed stream. Of course, as described above, a portion of the H2 of the first product stream can be used for other purposes, such as for catalyst activation as described herein.

[0049] In some embodiments, substantially all of the H2 of the second feed stream is derived from the first product stream. In fact, one skilled in the art can supply more H2 in the first feed stream than is required for the water-gas shift reaction in the first feed stream, supply an excess of H2 in the first product stream, and then supply the desired amount of H2 to the second feed stream for the Fischer-Tropsch process. However, in other embodiments, H2 can be provided to the second feed stream from other sources. For example, in various embodiments, H2 is provided to the second feed stream from an H2 source other than the first product stream. In FIG. 2, the H2 stream 226b from other sources is included in the second feed stream 221. One skilled in the art will understand that H2 can be supplied from various sources, such as gasification, reforming, or H2O electrolysis (including the electrolysis described herein). Further, as described in more detail below, H2 can be recycled from the second product stream to the second feed stream.

[0050] Based on the disclosure herein, one skilled in the art can adjust the relative amounts of H2 and CO in the second feed stream to provide the desired ratio. For example, more or less H2 from the first feed stream and / or more or less H2 from electrolysis can be included in the second feed stream. Similarly, more or less CO from the first feed stream and more or less CO from other sources (such as partial oxidation and reforming as described below) can be included in the second feed stream.

[0051] As described above, the Fischer-Tropsch process may desirably be carried out in the presence of significant levels of inert substances. One such inert substance, CO2, can be provided, for example, from the reverse water gas shift via the first product stream. Thus, in various embodiments described herein, the second feed stream comprises at least a portion of the CO2 of the first product stream. For example, in various embodiments, at least 10% of the CO2 of the first product stream, such as at least 25% of the CO2 of the first product stream, at least 50% of the CO2, at least 75% of the CO2, or at least 90% of the CO2 is included in the second feed stream. Of course, in other embodiments, the second feed stream may not contain a substantial amount of the CO2 of the first product stream. Thus, in various embodiments, the second feed stream does not contain a substantial amount of the CO2 of the first product stream. Generally, it may be desirable to recycle CO2 to the first feed stream for use in the reverse water gas shift reaction, but as will be described in more detail below, unreacted CO2 can be recycled from the second product stream to the first feed stream.

[0052] However, additionally or alternatively, it may be desirable for the second feed stream to contain additional inert components, which may be CO2 or other inert substances such as nitrogen and methane. For example, in various embodiments, one or more inert substances (e.g., CO2, nitrogen, and / or methane) are provided to the second feed stream from a source other than the first product stream. In FIG. 2, an inert substance stream 226c from another source is included in the second feed stream 221. Those skilled in the art will understand that inert substances can be provided from various sources. Further, as will be described in more detail below, inert substances can be recycled from the second product stream to the second feed stream.

[0053] As described above, it may be desirable to carry out the Fischer-Tropsch process steps in the presence of an inert substance. Thus, in various embodiments separately described herein, a portion of the first product stream contained in the second feed stream has a CO2 content in the range of 10 to 95 mol% CO2, for example, 10 to 90 mol%, or 10 to 85 mol%, or 10 to 80 mol%, or 10 to 75 mol%, or 10 to 70 mol%, or 20 to 95 mol%, or 20 to 90 mol%, or 20 to 85 mol%, or 20 to 80 mol%, or 20 to 70 mol%, or 30 to 95 mol%, or 30 to 90 mol%, or 30 to 85 mol%, or 30 to 80 mol%, or 30 to 75 mol%, or 30 to 70 mol% CO2.

[0054] Other gases may also be included in the second feed stream as described above. For example, as described above, it may be desirable to carry out the Fischer-Tropsch process steps in the presence of a significant amount of an inert substance (i.e., a component other than H2 or CO). For example, in various embodiments, the second feed stream contains one or more inert substances in an amount up to 80 mol%, for example, in the range of 3 - 80 mol%, or 5 - 80 mol%, or 10 - 80 mol%, or 15 - 80 mol%, or 30 - 80 mol%. In various embodiments, the second feed stream contains an inert substance in an amount of 70 mol% or less, 60 mol% or less, or 50 mol% or less, for example, in the range of 3 - 70 mol%, or 5 - 70 mol%, or 10 - 70 mol%, or 15 - 70 mol%, or 30 - 70 mol%, or 3 - 60 mol%, or 5 - 60 mol%, or 10 - 60 mol%, or 30 - 60 mol%, or 3 - 50 mol%, or 5 - 50 mol%, or 10 - 50 mol%, or 15 - 50 mol%, or 30 - 50 mol%. In various embodiments, the second feed stream contains one or more inert substances selected from CO2, methane, and nitrogen in an amount up to 80%, for example, up to 70 mol%, up to 60 mol%, or up to 50 mol%, or 15 - 70 mol%, or 30 - 70 mol%, or 15 - 60 mol%, or 30 - 60 mol%, or 15 - 50 mol%, or 30 - 50 mol%. In various embodiments, the second feed stream contains CO2 in an amount up to 80 mol%, for example, up to 70 mol%, up to 60 mol%, or up to 50 mol%, or 15 - 70 mol%, or 30 - 70 mol%, or 15 - 60 mol%, or 30 - 60 mol%, or 15 - 50 mol%, or 30 - 50 mol%.

[0055] One skilled in the art can adjust the portion of the first product stream included in the second feed stream to provide a desired H2:CO ratio. For example, in various embodiments, a portion of the first product stream included in the second feed stream has an H2:CO ratio in the range of 0.5:1 to 10:1, such as in the range of 1:1 to 2.5:1. Of course, no matter what the H2:CO ratio of a portion of the first product stream included in the second feed stream is, one skilled in the art can add H2 or CO as described above as needed to provide the desired ratio in the entire second feed stream.

[0056] As described above, the second feed stream contains both H2 and CO, and regardless of whether the second feed stream is provided as a mixture of feeds or as feeds provided separately to the reaction zone, the second feed stream includes all feeds to the Fischer-Tropsch reactor. In various embodiments of the present disclosure described herein, the second feed stream has an H2:CO ratio in the range of 0.5:1 to 6:1. In some embodiments, the second feed stream has an H2:CO ratio in the range of 1:1 to 3:1, or 1:1 to 2.5:1. In some embodiments, the second feed stream has an H2:CO ratio of at least 1.4:1. For example, in some embodiments, the second feed stream has an H2:CO ratio in the range of 1.4:1 to 3:1, or 1.4:1 to 2:1. One skilled in the art will provide the desired ratio of H2:CO in the second feed stream based on the disclosure herein that provides desired conversion rates and selectivities in the Fischer-Tropsch process.

[0057] As described above, it may be desirable to reduce the amount of water sent to the Fischer-Tropsch process step. Thus, in various embodiments described separately herein, a portion of the first product stream included in the second feed stream has a water content of 10 mol% or less, such as, or 2 mol% or less, or 0.5 mol% or less.

[0058] Also, as described above, it may be desirable to carry out the Fischer-Tropsch process in the presence of a relatively small amount of water. Thus, in various embodiments, the second feed stream has a water content of 10 mol% or less, for example, or 2 mol% or less, or 0.5 mol% or less.

[0059] The methods described herein include contacting a Fischer-Tropsch catalyst with the second feed stream described herein. The Fischer-Tropsch catalyst for use in the methods described herein is not particularly limited, and one of ordinary skill in the art will be able to select a catalyst appropriate for the desired Fischer-Tropsch product. In some embodiments, the Fischer-Tropsch catalyst includes cobalt, iron, rhodium, ruthenium, or combinations thereof.

[0060] For example, in some embodiments of the disclosure described herein, the Fischer-Tropsch catalyst includes cobalt in an amount in the range of 5 to 25 wt%, calculated as Co(0). The terms "calculated as Co(0)" and similar terms mean that the weight of the cobalt atoms / ions themselves is used in the calculation and not the total amount of any compounds or polynuclear ions to which those cobalt atoms / ions may be bound. For example, in various embodiments, the Fischer-Tropsch catalyst includes cobalt in an amount in the range of 7 to 25 wt%, or 10 to 25 wt%, or 5 to 20 wt%, or 7 to 20 wt%, or 10 to 20 wt%, calculated as Co(0). As will be understood by one of ordinary skill in the art, cobalt-based catalysts are often provided to the reaction zone in the form of cobalt oxide on a support, and the cobalt can be reductively activated in situ (e.g., with H2) to provide an active catalyst species having a significant concentration of Co(0).

[0061] In some embodiments, the Fischer-Tropsch catalyst comprises iron in an amount in the range of 5 to 95 wt%, calculated as Fe(0). For example, in various embodiments, the Fischer-Tropsch catalyst comprises iron in the range of 10 to 95 wt%, or 25 to 95 wt%, or 50 to 95 wt%, or 5 to 85 wt%, or 10 to 85 wt%, or 25 to 85 wt%, or 50 to 85 wt%, or 5 to 75 wt%, or 10 to 75 wt%, or 25 to 75 wt%, calculated as Fe(0). As will be understood by those skilled in the art, iron-based catalysts are often supplied to the reaction zone in the form of metallic iron or iron oxide, optionally on a support, and the iron can be activated (e.g., by reaction with H2 and CO) to provide an active catalyst species containing a significant concentration of iron carbide.

[0062] In various embodiments described herein, particularly when the catalyst is a cobalt-based catalyst, the Fischer-Tropsch catalyst further comprises manganese. For example, in various embodiments, the Fischer-Tropsch catalyst comprises manganese in an amount up to 15 wt%, e.g., up to 12 wt%, or up to 10 wt%, or up to 7 wt%, calculated as Mn(0). In certain such embodiments, the catalyst material comprises manganese in an amount in the range of 0.1 to 15 wt%, e.g., 0.1 to 10 wt%, or 0.1 to 5 wt%, 0.5 to 15 wt%, or 0.5 to 10 wt%, or 0.5 to 5 wt%, or calculated as Mn(0). Of course, in other embodiments, manganese is substantially absent (e.g., less than 0.1 wt% or less than 0.5 wt% manganese is present).

[0063] The Fischer-Tropsch catalysts suitable for use in the methods described herein can be in various forms and are not particularly limited. For example, the Fischer-Tropsch catalyst can be a supported catalyst or an unsupported catalyst. The form of the catalyst is not particularly limited, but in various desirable embodiments, the Fischer-Tropsch catalyst is a supported catalyst, and the support includes at least one of titanium oxide, zirconium oxide, cerium oxide, aluminum oxide, silicon oxide, and zinc oxide. For example, in various embodiments, the support includes at least one of titanium oxide, aluminum oxide, and silicon oxide. In some embodiments of the present disclosure described herein, the support is a titanium dioxide support.

[0064] Those skilled in the art will understand that the Fischer-Tropsch catalysts of the present disclosure can be provided in many forms, for example, in a fixed bed or as a fluidized bed, depending on the specific form of the reactor system in which they are used. The support of the Fischer-Tropsch catalyst can itself be provided as a discrete body of material, for example, as porous particles, pellets, or shaped extrudates, on which a metal is provided to provide the Fischer-Tropsch catalyst. However, in other embodiments, the Fischer-Tropsch catalysts of the present disclosure can themselves be formed as a layer on a underlying substrate. The underlying substrate is not particularly limited. It can be formed, for example, from a metal or a metal oxide and can itself be provided in many forms such as particles, pellets, shaped extrudates, or monoliths. Those skilled in the art will select the appropriate Fischer-Tropsch catalyst for a particular reactor system.

[0065] Similar to the rWGS catalyst, the Fischer-Tropsch catalyst is typically activated prior to use to provide, for example, cobalt(0) species on a cobalt-based catalyst or iron carbide species on an iron-based catalyst. Such activation can be performed before contacting the Fischer-Tropsch catalyst with a second feed stream.

[0066] For example, in some embodiments, the Fischer-Tropsch catalyst is activated by contact with a reducing gas. For example, hydrogen can be a particularly suitable gas for activating the Fischer-Tropsch catalyst, for example, when activation is a reduction to metal(0) species, as is the case for many cobalt-based catalysts. In various embodiments of the disclosure described elsewhere herein, the reducing gas comprises at least a portion of the H2 from the first product stream. For example, in some embodiments, the method further comprises separating at least a portion of the H2 of the first product stream and contacting it with the Fischer-Tropsch catalyst to activate the Fischer-Tropsch catalyst. In method 100 schematically shown in FIG. 1, at least a portion of hydrogen stream 125 is separated from the first product stream 112 and contacts the Fischer-Tropsch catalyst 123 to activate it. In other embodiments, the H2 present in the second feed stream can be used to activate the catalyst. As will be appreciated by those skilled in the art, the activation temperature can vary depending on the Fischer-Tropsch catalyst used. Thus, those skilled in the art will be able to select an appropriate temperature for activating the catalyst, for example, in the range of 200 to 400 °C.

[0067] In various embodiments, the Fischer-Tropsch catalyst is activated by contact with H2 and CO. This can be particularly suitable when the activation provides for conversion to carbides, such as for many iron-based catalysts. In various embodiments of the present disclosure described herein separately, the reducing gas comprises at least a portion of H2 and CO from the first product stream. For example, in some embodiments, the method further comprises separating at least a portion of the H2 and at least a portion of the CO of the first product stream and contacting the Fischer-Tropsch catalyst therewith to activate the Fischer-Tropsch catalyst. In method 200 schematically shown in FIG. 2, at least a portion of the H2 and CO stream 227 is separated from the first product stream 212 and contacted with the Fischer-Tropsch catalyst 223 to activate it. In other embodiments, the H2 and CO present in the second feed stream can be used to activate the catalyst. The activation temperature can vary, for example, in the range of 200 to 400 °C.

[0068] As described above, the method comprises contacting the Fischer-Tropsch catalyst with the second feed stream at a second temperature and a second pressure. One of ordinary skill in the art will select the appropriate reaction conditions in relation to the particular feedstock and catalyst used to provide the desired Fischer-Tropsch process. In some embodiments of the present disclosure described herein, the second temperature is in the range of 150 to 400 °C. For example, in various embodiments, the second temperature is in the range of 150 to 350 °C, or 150 to 300 °C, or 150 to 250 °C, or 150 to 200 °C, or 200 to 400 °C, or 200 to 350 °C, or 200 to 300 °C, or 200 to 250 °C, or 250 to 400 °C, or 250 to 350 °C, or 250 to 300 °C, or 300 to 400 °C. In some particular embodiments, the second temperature is in the range of 200 to 350 °C.

[0069] In particular, in many embodiments, the first temperature and the second temperature can be relatively close to each other. The inventors have noted that the reverse water gas shift catalysts described herein can provide suitable activity and CO selectivity even at relatively low temperatures. Thus, the first product stream can be provided at a temperature close to, or at least suitable for, the Fischer-Tropsch reaction step. This can desirably provide an increase in process integration. For example, in various embodiments, the first temperature is within 100 °C of the second temperature, such as within 50 °C of the second temperature, or within 25 °C of the second temperature.

[0070] However, in other embodiments, the first temperature and the second temperature are not so close to each other. The inventors have noted that in many cases, the desired reverse water gas shift process temperature is significantly higher than the desired Fischer-Tropsch process temperature. For example, in various embodiments, the first temperature is at least 100 °C higher than the second temperature, such as at least 150 °C higher than the second temperature, or at least 200 °C higher than the second temperature. The excess heat in the first product stream can be used for many purposes, such as to preheat at least a portion of the first feed stream, or as described above, to generate steam for use in power generation.

[0071] In some embodiments of the disclosure described herein, the second pressure ranges from 10 to 50 barg. For example, in various embodiments, the second pressure ranges from 20 to 50 barg, or 25 to 50 barg, or 10 to 40 barg, or 20 to 40 barg, or 25 to 40 barg, or 10 to 35 barg, or 20 to 35 barg, or 25 to 35 barg. In some embodiments, the second pressure ranges from 20 to 50 barg.

[0072] As is understood by those skilled in the art, the Fischer-Tropsch process described in this specification can be carried out at various GHSV (gas hourly space velocity) values. Thus, the GHSV for carrying out the Fischer-Tropsch reaction is not particularly limited. For example, in some embodiments of the present disclosure, the method for carrying out the Fischer-Tropsch reaction is carried out at a GHSV in the range of 1,000 to 2,000,000 h-1. In various embodiments, the method for carrying out the reverse water gas shift reaction is carried out at a GHSV in the range of 1,000 to 1,200,000 h-1, or 1,000 to 500,000 h-1, or 1,000 to 100,000 h-1, or 5,000 to 1,200,000 h-1, or 5,000 to 500,000 h-1, or 5,000 to 100,000 h-1, or 10,000 to 1,200,000 h-1, or 10,000 to 500,000 h-1, or 10,000 to 100,000 h-1. In various embodiments of the present disclosure, the method for carrying out the Fischer-Tropsch reaction is carried out at a GHSV in the range of 1,000 to 50,000 h-1, or 2,000 to 50,000 h-1, or 5,000 to 50,000 h-1, or 10,000 to 50,000, or 1,000 to 40,000 h-1, or 2,000 to 40,000 h-1, or 5,000 to 40,000 h-1, or 10,000 to 40,000 h-1, or 1,000 to 30,000 h-1, or 2,000 to 30,000 h-1, or 5,000 to 30,000 h-1, or 10,000 to 30,000 h-1.

[0073] The Fischer-Tropsch process is typically used to produce C5+ hydrocarbons, such as unsubstituted C5+ hydrocarbons (e.g., alkanes and alkenes) and oxygenated C5+ hydrocarbons (e.g., C5+ alcohols, aldehydes, ketones, carboxylic acids). In various embodiments of the disclosure described herein, contacting a Fischer-Tropsch catalyst with a second feed stream to provide a second product stream is carried out with at least 30%, such as at least 50%, or at least 70% C5+ selectivity (i.e., with respect to all C5+ species). For example, in some embodiments, the selectivity for C5+ alkanes is at least 30%, such as at least 50%, or at least 70%. In some embodiments, the selectivity for C5+ alkanes and C5+ alcohols is at least 30%, such as at least 50%, or at least 70%.

[0074] Additional components may be present in the second product stream. For example, in some embodiments, the second product stream includes water, which is another product of the Fischer-Tropsch reaction. Also, one or more light hydrocarbons (i.e., C1-C4) may be present as by-products. CO and / or H2 may be present, for example, as unreacted materials from the second feed stream. CO2 or other inert substances described herein may also be present. Such components of the second product stream can be separated and / or recycled in various ways.

[0075] For example, in various embodiments, the method further includes separating at least a portion of water from the second product stream. This is schematically illustrated in FIG. 3. In the embodiment of FIG. 3, the water-gas shift catalyst 313 and the Fischer-Tropsch catalyst 323 are provided in separate beds within the same reactor. Thus, the first reaction zone 310 is the volume of the reactor 305 that includes the bed 314 containing the water-gas shift catalyst 313, and the second reaction zone 320 is the volume of the reactor 305 that includes the bed 324 containing the Fischer-Tropsch catalyst 323. The first feed stream 311 contacts the water-gas shift catalyst 313 to provide a first product stream 312, which is sent directly to the Fischer-Tropsch catalyst 323 as the second feed stream 321 to provide a second product stream 322. Here, the method also optionally includes separating at least a portion (e.g., at least 50%, at least 75%, or at least 90%) of water from the second product stream 322 to provide a water-containing stream 334.

[0076] Light hydrocarbons are often not the desired portion of the Fischer-Tropsch products used as fuels or lubricants, but are useful in themselves for many purposes. Thus, in various embodiments, the method further includes separating at least a portion of C1-C4 hydrocarbons from the second product stream to provide a light hydrocarbon stream. The light hydrocarbon stream can be recycled, for example, to the first feed stream or the second feed stream. For example, in the method 200 of FIG. 2, the light hydrocarbons can be provided as part of a recycle stream 236 that is part of the second feed stream 221. In the method 300 of FIG. 3, the light hydrocarbons can be provided as part of a recycle stream 336 that is part of the first feed stream 311. In the method 400 of FIG. 4, the light hydrocarbons are recycled to the first feed stream 411 via a recycle stream 442.

[0077] The light hydrocarbon stream has other uses. For example, in some embodiments, the method further includes oxidizing at least a portion of the light hydrocarbon stream to provide a CO and / or CO2-containing partial oxidation (pOX) stream, and including at least a portion of the pOX stream in a first feed stream and / or a second feed stream. An example of such a method is schematically shown in FIG. 4, where method 400, first feed stream 411, first product stream 412, reverse water gas shift catalyst 413, second feed stream 421, second product stream 422, and Fischer-Tropsch catalyst 423 may be as described separately herein. Here, the method includes oxidizing at least a portion of the light hydrocarbon stream 450 in the partial oxidation reaction zone 452 to provide a CO and / or CO2-containing pOX stream, and including at least a portion of the pOX stream 454 in the first feed stream 411 and / or the second feed stream 421.

[0078] Other methods can be used to provide CO and / or CO2 from the light hydrocarbon stream. For example, reforming techniques such as steam reforming and autothermal reforming can be used to provide CO by reacting hydrocarbons with water. Thus, in various embodiments, the method further includes reforming (e.g., steam reforming and / or autothermal reforming) at least a portion of the light hydrocarbon stream to provide a CO and / or CO2-containing reformed stream, and including at least a portion of the reformed stream in the first feed stream and / or the second feed stream. Water separated from the first and / or second product streams can be provided as part of the feed to the reforming described herein.

[0079] Furthermore, the light hydrocarbon stream can be combusted to provide thermal energy, which can be used to heat various process streams or generate electricity. Thus, in various embodiments, the method includes combusting at least a portion of the light hydrocarbon stream to provide energy, such as thermal energy or electrical energy. For example, in method 400 of FIG. 4, a portion of light hydrocarbon stream 450 is combusted in a power generation zone (here, generator 470) to generate an electrical current 472. In various embodiments, the thermal energy may be used to provide the heat load required for the reverse water gas shift process. For example, in method 400 of FIG. 4, a portion of light hydrocarbon stream 450 is combusted in a power generation zone (here, heat generator 480) to generate a heat stream 482. The heat stream 482 is directed to heat exchange zone 490 to heat the first feed stream 411. The thermal energy can similarly be supplied to the Fischer-Tropsch reaction. Also, as will be appreciated by those skilled in the art, other processing of the light hydrocarbon stream (e.g., partial oxidation) can provide energy, which can be used, for example, as described herein.

[0080] Similar to the first product stream, heat can be exchanged from the second product stream to supply heat, for example, to a feed stream or a steam generation zone. For example, in various embodiments, the method further includes exchanging heat between at least a portion of the second product stream and at least a portion of the first feed stream, thereby cooling at least a portion of the second product stream and heating at least a portion of the first feed stream. In the method 300 of FIG. 3, heat is exchanged between at least a portion of the second product stream 322 and the first feed stream 311 in the second heat exchange zone 330, thereby cooling the second product stream 322 and heating the first feed stream 311. Of course, heat can also be exchanged from the second product stream to the second feed stream. For example, in various embodiments, the method further includes exchanging heat between at least a portion of the second product stream and at least a portion of the second feed stream, thereby cooling at least a portion of the second product stream and heating at least a portion of the second feed stream. In the method 400 of FIG. 4, heat is exchanged between at least a portion of the second product stream 422 and the second feed stream 421 within the second heat exchange zone 430, thereby cooling the second product stream 422 and heating the second feed stream 421. Those skilled in the art will understand that a variety of heat exchangers can be used for this purpose.

[0081] Of course, any excess heat in the second product stream can be additionally or alternatively used for other purposes. For example, in various embodiments, the method further includes exchanging heat between at least a portion of the second product stream and a steam generation zone, thereby cooling at least a portion of the second product stream and providing heat to the steam generation zone. This is shown in FIG. 3. Here, after heat exchange with the first feed stream 311, the second product stream 322 is directed to the steam generation zone 332 to cool the second product stream 322 and provide heat to the steam generation zone 332. Steam can be generated from the supplied heat, and electricity can be generated from the steam (not shown here).

[0082] It may be desirable to recycle hydrogen from the second product stream to, for example, the first feed stream and / or the second feed stream. For example, in various embodiments, the method includes recycling at least a portion of the H2 in the second product stream to the second feed stream. For example, in the method of FIG. 2, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the H2 in the second product stream can be recycled to the second feed stream 221 via recycle stream 236. In various embodiments, the method includes recycling at least a portion of the H2 in the second product stream to the first feed stream. For example, in the method of FIG. 3, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the H2 in the second product stream can be recycled to the first feed stream 311 via recycle stream 336. In various embodiments, at least 25%, for example at least 50%, of the H2 in the second product stream is recycled to the first feed stream or the second feed stream. In various embodiments, at least 75%, for example at least 90%, of the H2 in the second product stream is recycled to the first feed stream or the second feed stream.

[0083] In some cases, for example, when H2 is provided to the second feed stream from an H2 source other than the first product stream, the H2 from the second product stream can constitute a majority, e.g., at least 90%, at least 95%, or at least 98% of the H2 in the first feed stream. This is shown, for example, in FIG. 4. Here, the primary H2 input to the method passes through stream 440 which is part of the second feed stream 421. The H2 in the second product stream is included in recycle stream 442, which becomes part of the first feed stream 411.

[0084] Similarly, it may be desirable to recycle the CO of the second product stream to, for example, the first feed stream and / or the second feed stream. For example, in various embodiments, the method includes recycling at least a portion of the CO of the second product stream to the second feed stream. For example, in the method of FIG. 2, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the CO of the second product stream can be recycled to the second feed stream 221 via recycle stream 236. In various embodiments, the method includes recycling at least a portion of the CO of the second product stream to the first feed stream. For example, in the method of FIG. 3, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the CO of the second product stream can be recycled to the first feed stream 311 via recycle stream 336. In various embodiments, at least 25%, for example at least 50%, of the CO of the second product stream is recycled to the first feed stream or the second feed stream. In various embodiments, at least 75%, for example at least 90%, of the CO of the second product stream is recycled to the first feed stream or the second feed stream.

[0085] Often, both the CO and H2 of the second product stream are recycled.

[0086] Furthermore, when using one or more inert substances in the Fischer-Tropsch process step, it may be desirable to recycle them. For example, in various embodiments, the method includes recycling at least a portion of the inert substances of the second product stream to the second feed stream. For example, in the method of FIG. 2, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the inert substances of the second product stream can be recycled to the second feed stream 221 via recycle stream 236. In various embodiments, the method includes recycling at least a portion of the inert substances of the second product stream to the first feed stream. For example, in the method of FIG. 3, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the inert substances of the second product stream can be recycled to the first feed stream 311 via recycle stream 336. In various embodiments, at least 25%, for example at least 50% of the inert substances of the second product stream are recycled to the first feed stream or the second feed stream. In various embodiments, at least 75%, for example at least 90% of the inert substances of the second product stream are recycled to the first feed stream or the second feed stream. In various embodiments, the purge stream can be incorporated with the recycle stream to prevent uncontrolled accumulation of inert substances in the recycle stream (not shown here).

[0087] Specifically, since CO2 is the carbon source in the reverse water gas shift process step, it may be particularly desirable to recycle CO2 to the first feed stream. Thus, in various embodiments, the method includes recycling at least a portion (e.g., at least 50%, at least 75%, or at least 90%) of the CO2 of the second product stream to the first feed stream. For example, in the method of FIG. 3, at least a portion (e.g., at least 50%, at least 75%, or at least 90%) of the CO2 of the second product stream can be recycled to the first feed stream 311 via recycle stream 336.

[0088] In some cases, for example, when CO2 is provided to a second feed stream from a CO2 source other than the first product stream, the CO2 from the second product stream can constitute a majority of the CO2 in the first feed stream, such as at least 90%, at least 95%, or at least 98% of the CO2 in the first feed stream. This is shown, for example, in FIG. 4. Here, the primary CO2 input to the process passes through a stream 440 that is part of the second feed stream 421. The CO2 in the second product stream is included in a recycle stream 442, which becomes part of the first feed stream 411.

[0089] As described above, the Fischer-Tropsch process step provides a second product stream that includes C5+ hydrocarbons (e.g., unsubstituted hydrocarbons such as alkanes and alkenes, and / or oxygenated hydrocarbons such as alcohols). Thus, in various embodiments, one or more products are provided from at least a portion of the C5+ hydrocarbons in the second product stream. C5+ hydrocarbons can be used as a basis for various fuels such as gasoline, diesel, and aviation fuel. Other products such as waxes and lubricants can also be manufactured. Alkenes and oxygenates can also be used as feedstocks in various other processes.

[0090] One of ordinary skill in the art will use conventional post-treatment techniques to convert the C5+ hydrocarbon-containing product into a desired product such as a desired fuel. For example, in various embodiments, the method further includes hydrotreating at least a portion of the C5+ hydrocarbons in the second product stream. As will be understood by one of ordinary skill in the art, hydrotreating is the treatment of a hydrocarbon stream with hydrogen in the presence of a suitable catalyst. A wide variety of hydrotreating techniques are known, and one of ordinary skill in the art will apply them here. For example, in the method 300 of FIG. 3, the second product stream 322 is hydrotreated in a hydrotreating reactor 350 to provide a hydrotreated product stream 352. As described above, CO2 and H2 are substantial inputs to the claimed method. Advantageously, the inventors recognize that each of these can be derived from a renewable or environmentally responsible source.

[0091] CO2 can generally be captured from the environment or more directly from processes that form CO2 (especially in sectors where it is difficult to remove). This can make the final hydrocarbon product substantially carbon neutral or of lower carbon intensity. Thus, in some embodiments of the disclosure described herein, at least a portion of the CO2 in the first feed stream and / or the second feed stream is derived from a renewable source. In some embodiments, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the CO2 in the first feed stream and / or the second feed stream is from direct air capture. In some embodiments, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the CO2 in the first feed stream and / or the second feed stream is from a manufacturing plant such as a bioethanol plant (e.g., CO2-producing fermentation), a steel mill, or a cement factory. Thus, the rWGS-Fischer Tropsch integration method of the disclosure described herein is not only carbon neutral but, in some cases, can be a net consumer of carbon dioxide. These advantages make the integrated method very attractive, particularly for decarbonizing transportation fuels for both the automotive and aviation sectors, since the carbon monoxide produced in the rWGS reaction can be readily utilized by established techniques for synthesizing liquid hydrocarbon fuels by the Fischer Tropsch process.

[0092] Similarly, H2 can be provided from environmentally responsible sources. In some embodiments, at least a portion of the H2 in the first feed stream and / or the second feed stream is from renewable sources. For example, in various embodiments, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the H2 in the first feed stream and / or the second feed stream can be so-called "green" hydrogen produced, for example, from the electrolysis of water operated using renewable electricity (such as wind, solar, or hydroelectric power). In some embodiments, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the H2 in the first feed stream and / or the second feed stream can be from so-called "blue" sources, for example, from natural gas reforming methods with carbon capture. Of course, other H2 sources can be used in part or in whole. For example, in some embodiments, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the H2 in the first feed stream and / or the second feed stream is gray hydrogen, black hydrogen, brown hydrogen, pink hydrogen, turquoise hydrogen, yellow hydrogen, and / or white hydrogen.

[0093] The inventors have noted that the electrolysis of water is a desirable method for providing hydrogen to the claimed processes. Thus, in some embodiments, the method includes providing at least a portion of H2 to the first feed stream and / or the second feed stream by electrolysis of water. However, the inventors have noted that electricity can be generated as part of the claimed process, for example, using heat exchange from the first or second product stream, or by burning light hydrocarbons as described above. In some embodiments, the electrolysis of water is performed using at least in part electricity generated according to the methods described herein. For example, in method 200 of FIG. 2, water 262 separated from the first product stream is electrolyzed in electrolyzer 260 using electricity 264 generated from steam created in steam generation zone 232 by heat exchange from the first product stream. The H2 generated by electrolysis is supplied to the first feed stream via stream 265. In some embodiments, at least a portion of the O2 generated by electrolysis is provided to the partial oxidation reaction zone as described herein and shown in the embodiment of FIG. 6. Hydrogen from electrolysis can also be burned to provide thermal energy, for example, this can be used to heat the first feed stream.

[0094] The methods described herein can be operated in a wide variety of reactor systems. In some embodiments, a first reaction zone (i.e., where the reverse water gas shift process step is performed) includes a first reactor in which a reverse water gas shift catalyst is disposed, and a second reaction zone (i.e., where the Fischer-Tropsch process step is performed) includes a second reactor in which a Fischer-Tropsch catalyst is disposed. Examples of such methods are schematically shown in FIGS. 1, 2, and 4. In these examples, the methods (100, 200, 400) are performed in a reactor system that includes a first reactor (110, 210, 410) in which a reverse water gas shift catalyst (113, 213, 413) is disposed and a second reactor (120, 220, 420) in which a Fischer-Tropsch catalyst (123, 223, 423) is disposed. The reactors used in the integrated methods of the present disclosure described herein are not particularly limited, and those skilled in the art can select appropriate reactors.

[0095] However, other embodiments are possible. For example, in some embodiments, the method is performed in a reactor system that includes a first catalyst bed in which a reverse water gas shift catalyst is disposed, and the second reaction zone includes a second catalyst bed in which a Fischer-Tropsch catalyst is disposed. In some embodiments, the first reactor bed and the second reactor bed are disposed within the same reactor. Such a configuration is shown in FIG. 3, where the reverse water gas shift catalyst 313 is disposed in the first catalyst bed 314 and the Fischer-Tropsch catalyst 323 is disposed in the second catalyst bed 324. Here, the catalyst beds 314 and 324 are within the same reactor 305, and the process gas flows between them. Such a configuration is particularly desirable when the first temperature and the second temperature are relatively close to each other.

[0096] In various embodiments, the method is performed in a reactor system that includes one or more first catalyst vessels in which a reverse water gas shift catalyst is disposed, and the second reaction zone includes one or more second catalyst vessels in which a Fischer-Tropsch catalyst is disposed. These can be provided within the same reactor as described above with respect to the catalyst beds.

[0097] As described above, the reverse water gas shift process step and the Fischer-Tropsch process step using the catalyst described in this specification can be carried out under similar conditions. Therefore, in various embodiments, the reverse water gas shift catalyst and the Fischer-Tropsch catalyst can be provided together in the same catalyst bed, for example, they can be mixed together. Such an embodiment is shown in FIG. 5. Here, the method 500 is carried out in a reactor system including a reactor 505, in which the reverse water gas shift catalyst 513 and the Fischer-Tropsch catalyst 523 are mixed together in a single catalyst bed 524. Here, the first feed stream 511 and the second product stream 522 can be substantially as described in this specification. The first product stream and the second feed stream are understood to be a mixture of process gases in the mixed catalyst.

[0098] In particular, in the above-described embodiments, separate rWGS catalysts and Fischer-Tropsch catalysts can be used, for example, in separate reactors, in separate regions of the same reactor, or even mixed in the same region of the reactor.

[0099] However, the inventors also note that there are certain commonalities between the rWGS catalysts described herein and certain Fischer-Tropsch catalysts. For example, as will be understood by those skilled in the art, manganese is a common modifier used in Fischer-Tropsch catalysts, particularly cobalt-based catalysts. The inventors also note that similar supports can be used for each.

[0100] Accordingly, in addition to the above configurations, the inventors contemplate providing a single bifunctional catalyst having both reverse water gas shift activity and Fischer-Tropsch activity. Such a bifunctional catalyst includes both an rWGS-active catalyst metal and a Fischer-Tropsch-active catalyst metal in the same body. Those skilled in the art will understand that both the rWGS catalyst and the Fischer-Tropsch catalyst are supported catalysts, e.g., metal oxide supported catalysts. Thus, in various embodiments of the present disclosure, the rWGS-active catalyst metal and the Fischer-Tropsch-active catalyst metal can be provided together on the same support to provide a bifunctional catalyst. For example, in some embodiments, the support of the bifunctional catalyst is itself provided as an individual body of material such as, e.g., porous particles, pellets, or shaped extrudates, and the rWGS-active catalyst metal and the FT-active catalyst metal are provided thereon to provide a bifunctional catalyst. The rWGS-active catalyst metal and the FT-active catalyst metal may be uniformly distributed throughout the support or may be distributed in discrete regions throughout the support. However, in other embodiments, the bifunctional catalyst of the present disclosure can itself be formed as a layer on a underlying substrate. For example, in some embodiments, the bifunctional catalyst is formed from a layer of rWGS-active catalyst metal and a layer of FT-active catalyst metal on a underlying substrate. The rWGS-active catalyst metal and the FT-active catalyst metal may be uniformly distributed on the underlying substrate. In other embodiments, the rWGS-active catalyst metal and the FT-active catalyst metal may be in separate regions on the underlying substrate. The underlying substrate is not particularly limited. It can be formed, e.g., from a metal or a metal oxide and can itself be provided in many forms such as, e.g., particles, pellets, shaped extrudates, or monoliths.

[0101] The dual-functional catalyst comprises a support material, an rWGS-active catalyst metal as described herein, and a Fischer-Tropsch-active catalyst metal as described herein. For example, the dual-functional catalyst comprises a support which is a metal oxide support comprising at least one of titanium oxide, zirconium oxide, cerium oxide, or aluminum oxide. The rWGS-active catalyst metal and the Fischer-Tropsch-active catalyst metal are not particularly limited, and one skilled in the art will be able to select a suitable metal. For example, one skilled in the art can select a suitable rWGS-active metal as described in Daza et al., “CO2 Conversion by Reverse Water Gas Shift Catalysts: Comparison of Catalysts, Mechanisms and the Outcomes They Bring” RSC Adv., 2016, 6, 49675-49691, Zhu et al., “Catalytic Reduction of CO2 by the Reverse Water Gas Shift Reaction: Recent Advances in the Design of Active and Selective Supported Metal Catalysts”, Transaction of Tianjin University, 2020, 26, 172-187, and Chen et al., “Recent Advances in Supported Metal Catalysts and Oxide Catalysts for the Reverse Water Gas Shift Reaction”, Front. Chen., 2020, 8, 709. For example, the rWGS-active metal may be selected from copper, platinum, palladium, rhodium, rhenium, ruthenium, nickel, gold, and iridium, or combinations thereof. Similarly, one skilled in the art will be able to select a suitable Fischer-Tropsch-active metal as described herein. For example, the Fischer-Tropsch-active metal may be selected from cobalt, iron, rhodium, ruthenium, manganese, or combinations thereof.

[0102] The ratio of the rWGS-active catalyst metal to the FT-active catalyst metal in the dual-functional catalyst is not particularly limited, and one skilled in the art can select a suitable ratio. For example, in some embodiments, the ratio of the rWGS-active catalyst metal to the FT-active catalyst metal in the dual-functional catalyst is at least 0.1:1. In various embodiments, the ratio of the rWGS-active catalyst metal to the FT-active catalyst metal in the dual-functional catalyst is at least 0.2:1, or 0.5, or 1:1.

[0103] Such catalysts can be used in embodiments such as those described with respect to FIG. 5. One of ordinary skill in the art will select reaction conditions that provide an appropriate balance of reverse water gas shift activity and Fischer-Tropsch activity.

[0104] FIG. 6 is a schematic diagram of another integrated method according to the present disclosure. Here, the reverse water gas shift and Fischer-Tropsch process steps are integrated with the partial oxidation of light hydrocarbons to provide CO and H2 to the Fischer-Tropsch process step, electrolysis to provide H2 for the reverse water gas shift process step and O2 for the partial oxidation, and various recycles and any feedstocks, as described throughout this specification.

[0105] Further aspects of the present disclosure are provided by the embodiments listed below, which may be combined in any number and in any combination that is not logically or technically inconsistent.

[0106] Embodiment 1. A method for performing an integrated Fischer-Tropsch process, comprising: forming a first feed stream comprising H2 and CO2; contacting a reverse water gas shift catalyst with the first feed stream at a first temperature and a first pressure in the range of 200 to 900 °C to perform a reverse water gas shift reaction to form a first product stream comprising CO and H2, the first product stream having a lower CO2 concentration and a higher CO concentration than the first feed stream; contacting a Fischer-Tropsch catalyst with a second feed stream comprising H2 and at least a portion of the CO of the first product stream at a second temperature and a second pressure to form a second product stream comprising C5+ hydrocarbons.

[0107] Embodiment 2. The method according to Embodiment 1, wherein the molar ratio of H2 to CO2 in the first feed stream is at least 0.1:1, for example, at least 0.5:1.

[0108] Embodiment 3. The method according to Embodiment 1 or Embodiment 2, wherein the molar ratio of H2 to CO2 in the first feed stream is at least 0.9:1, for example, at least 1:1 or at least 1.5:1.

[0109] Embodiment 4. The method according to any one of Embodiments 1 to 3, wherein the molar ratio of H2 to CO2 in the first feed stream is at least 2:1, for example, at least 2.5:1.

[0110] Embodiment 5. The method according to any one of Embodiments 1 to 4, wherein the molar ratio of H2 to CO2 in the first feed stream is 100:1 or less, for example, 75:1 or less, or 50:1 or less.

[0111] Embodiment 6. The method according to any one of Embodiments 1 to 4, wherein the molar ratio of H2 to CO2 in the first feed stream is 20:1 or less, for example, 15:1 or less, or 10:1 or less.

[0112] Embodiment 7. The method according to any one of Embodiments 1 to 6, wherein the molar ratio of H2 to CO2 in the first feed stream is in the range of 0.5:1 to 10:1.

[0113] Embodiment 8. The method according to any one of Embodiments 1 to 7, wherein the first feed stream further contains CO.

[0114] Embodiment 9. The method according to any one of Embodiments 1 to 8, wherein the first feed stream further contains one or more inert gases (for example, nitrogen and / or methane).

[0115] Embodiment 10. The method according to any one of Embodiments 1 to 9, wherein the reverse water gas shift reaction has a CO selectivity of at least 70%, for example, at least 80%.

[0116] Embodiment 11. The method according to any one of Embodiments 1 to 9, wherein the reverse water gas shift reaction has a CO selectivity of at least 85%, for example, or at least 90%.

[0117] Embodiment 12. The method according to any one of Embodiments 1 to 11, wherein the reverse water gas shift reaction has a CO selectivity of at least 95%, for example, at least 96%.

[0118] Embodiment 13. The method according to any one of Embodiments 1 to 11, wherein the reverse water gas shift reaction has a CO selectivity of at least 98%, for example, or at least 99%.

[0119] Embodiment 14. The method according to any one of Embodiments 1 to 13, wherein the reverse water gas shift reaction has a methane selectivity of 5% or less, for example, 4% or less.

[0120] Embodiment 15. The method according to any one of Embodiments 1 to 13, wherein the reverse water gas shift reaction has a methane selectivity of 2% or less, for example, 1% or less.

[0121] Embodiment 16. The method according to any one of Embodiments 1 to 13, wherein the reverse water gas shift reaction has a methane selectivity of 0.5% or less, for example, 0.2% or less.

[0122] Embodiment 17. The method according to any one of Embodiments 1 to 16, wherein the reverse water gas shift reaction has a CO2 conversion rate of at least 5%, for example, at least 10%, or 20%.

[0123] Embodiment 18. The method according to any one of Embodiments 1 to 16, wherein the reverse water gas shift reaction has a CO2 conversion rate of at least 30%, for example, at least 40%.

[0124] Embodiment 19. The method according to any one of Embodiments 1 to 18, wherein the reverse water gas shift reaction has a CO2 conversion rate of 90% or less, for example, 80% or less, or 70% or less.

[0125] Embodiment 20. The method according to any one of Embodiments 1 to 18, wherein the reverse water gas shift reaction has a CO2 conversion rate of 65% or less, for example, 60% or less.

[0126] Embodiment 21. The method according to any one of Embodiments 1 to 20, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 200 to 850 °C, for example, in the range of 200 to 800 °C, 200 to 750 °C, 200 to 700 °C, or 200 to 650 °C, or 200 to 600 °C.

[0127] Embodiment 22. The method according to any one of Embodiments 1 to 20, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 250 to 900 °C, for example, in the range of 250 to 850 °C, or 250 to 800 °C, or 250 to 750 °C, or 250 to 700 °C, or 250 to 650 °C, or 250 to 600 °C.

[0128] Embodiment 23. The method according to any one of Embodiments 1 to 20, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 300 to 900 °C, for example, in the range of 200 to 850 °C, or 200 to 800 °C, or 300 to 750 °C, or 300 to 700 °C, or 300 to 650 °C, or 300 to 600 °C.

[0129] Embodiment 24. The method according to any one of Embodiments 1 to 20, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 350 to 900 °C, for example, in the range of 350 to 850 °C, or 350 to 800 °C, or 350 to 750 °C, or 350 to 700 °C, or 350 to 650 °C, or 350 to 600 °C.

[0130] Embodiment 25. The method according to any one of Embodiments 1 to 20, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 400 to 900 °C, for example, in the range of 400 to 850 °C, or 400 to 800 °C, or 400 to 750 °C, or 400 to 700 °C, or 400 to 650 °C, or 400 to 600 °C.

[0131] Embodiment 26. The method according to any one of Embodiments 1 to 20, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 450 to 900 °C, for example, in the range of 450 to 850 °C, or 450 to 800 °C, or 450 to 750 °C, or 450 to 700 °C, or 450 to 650 °C, or 450 to 600 °C.

[0132] Embodiment 27. The method according to any one of Embodiments 1 to 20, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 500 to 900 °C, for example, in the range of 500 to 850 °C, or 500 to 800 °C, or 500 to 750 °C, or 500 to 700 °C, or 500 to 650 °C, or 500 to 600 °C.

[0133] Embodiment 28. The method according to any one of Embodiments 1 to 20, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 550 to 900 °C, for example, in the range of 550 to 850 °C, or 550 to 800 °C, or 550 to 750 °C, or 550 to 700 °C, or 550 to 650 °C, or 550 to 600 °C.

[0134] Embodiment 29. The method according to any one of Embodiments 1 to 20, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 200 to 500 °C, for example, in the range of 200 to 450 °C, or 200 to 400 °C, or 200 to 350 °C, or in the range of 250 to 500 °C, for example, 250 to 450 °C, or 250 to 400 °C, or 250 to 350 °C.

[0135] Embodiment 30. The method according to any one of Embodiments 1 to 29, wherein the reverse water gas shift reaction is carried out at a pressure in the range of 1 to 100 barg (for example, in the range of 1 to 70 barg, or 1 to 50 barg, or 1 to 40 barg, or 1 to 35 barg, or 5 to 80 barg, or 5 to 50 barg, or 5 to 40 barg, or 5 to 35 barg, or 10 to 70 barg, 10 to 50 barg, or 10 to 40 barg, or 10 to 35 barg, or 20 to 70 barg, 20 to 50 barg, or 20 to 40 barg, or 20 to 35 barg, or 25 to 70 barg, 25 to 50 barg, or 25 to 40 barg, or 25 to 35 barg).

[0136] Embodiment 31. The method according to any one of Embodiments 1 to 30, wherein the reverse water gas shift reaction is carried out at a GHSV in the range of 1,000 to 2,000,000 h-1 (for example, in the range of 1,000 to 1,200,000 h-1, or 1,000 to 500,000 h-1, or 1,000 to 100,000 h-1, or 5,000 to 1,200,000 h-1, or 5,000 to 500,000 h-1, or 5,000 to 100,000 h-1, or 10,000 to 1,200,000 h-1, or 10,000 to 500,000 h-1, or 10,000 to 100,000 h-1).

[0137] Embodiment 32. The method according to any one of Embodiments 1 to 46, including activating the reverse water gas shift catalyst, for example, before contacting the reverse water gas shift catalyst with the first feed stream.

[0138] Embodiment 33. The method according to Embodiment 32, wherein activating the rWGS catalyst includes contacting the rWGS catalyst with a reducing stream containing a reducing gas (for example, hydrogen).

[0139] Embodiment 34. The method according to Embodiment 32 or Embodiment 33, wherein the reducing stream contains at least 25 mol% (for example, at least 50 mol%, or 75 mol%, or 90 mol%) of hydrogen.

[0140] Embodiment 35. The method according to any one of Embodiments 32 to 34, wherein the activation of the rWGS catalyst is carried out at a temperature in the range of 200°C to 800°C (for example, in the range of 250°C to 800°C, or 300°C to 800°C, or 200°C to 700°C, or 250°C to 700°C, or 300°C to 700°C).

[0141] Embodiment 36. The method according to any one of Embodiments 32 to 35, wherein by activating the rWGS catalyst, a catalyst with at least 10% (for example, at least 25%, or 50%) reduction is obtained.

[0142] Embodiment 37. The method according to any one of Embodiments 1 to 36, wherein the first product stream contains 95 mol% or less of CO2 (for example, 90 mol% or less of CO2).

[0143] Embodiment 38. The method according to any one of Embodiments 1 to 36, wherein the first product stream contains 85 mol% or less of CO2 (for example, 80 mol% or less of CO2).

[0144] Embodiment 39. The method according to any one of Embodiments 1 to 36, wherein the first product stream contains 75 mol% or less of CO2 (for example, 70 mol% or less of CO2).

[0145] Embodiment 40. The method according to any one of Embodiments 1 to 36, wherein the first product stream contains CO2 in the range of 5 to 95 mol%, for example, 5 to 90 mol%, or 5 to 85 mol%, or 5 to 80 mol%, or 5 to 75 mol%, or 5 to 70 mol%, or 10 to 95 mol%, or 10 to 90 mol%, or 10 to 85 mol%, or 10 to 80 mol%, or 10 to 75 mol%, or 10 to 70 mol%, or 20 to 95 mol%, or 20 to 90 mol%, or 20 to 85 mol%, or 30 to 85 mol%, or 30 to 80 mol%, or 30 to 75 mol%, or 30 to 70 mol%.

[0146] Embodiment 41. The method according to any one of Embodiments 1 to 40, wherein the first product stream contains 20 mol% or less of methane, for example, 15 mol% or less of methane.

[0147] Embodiment 42. The method according to any one of Embodiments 1 to 40, wherein the first product stream contains 10 mol% or less of methane, for example, 5 mol% or less, or 1 mol% or less, or 0.5 mol% or less, or 0.1 mol% or less of methane.

[0148] Embodiment 43. The method according to any one of Embodiments 1 to 42, wherein the ratio of H2:CO in the first product stream is at most 100:1, for example, at most 50:1, or at most 25:1, or at most 10:1.

[0149] Embodiment 44. The method according to any one of Embodiments 1 to 42, wherein the ratio of H2:CO in the first product stream is in the range of 0.1:1 to 100:1 (for example, in the range of 0.1:1 to 50:1, or 0.1:1 to 25:1, or 0.1:1 to 10:1, or 0.1:1 to 5:1, or 1:1 to 100:1, or 1:1 to 50:1, or 1:1 to 25:1, or 1:1 to 10:1, or 1:1 to 5:1).

[0150] Embodiment 45. The method according to any one of Embodiments 1 to 44, further comprising separating the first product stream and recycling at least a portion of one or more components of the first product stream to the first feed stream.

[0151] Embodiment 46. The method according to any one of Embodiments 1 to 45, further comprising separating the first product stream and recycling at least a portion (for example, at least 5 mol%, at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, or at least 90 mol%) of the CO2 in the first product stream to the first feed stream.

[0152] Embodiment 47. The method according to any one of Embodiments 1 to 46, further comprising separating the first product stream and recycling at least a portion (for example, at least 5 mol%, at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, or at least 90 mol%) of the H2 in the first product stream to the first feed stream.

[0153] Embodiment 48. The method according to any one of Embodiments 1 to 47, further comprising separating at least a portion of H2 and / or CO from the first product stream and contacting it with the Fischer-Tropsch catalyst to activate the Fischer-Tropsch catalyst.

[0154] Embodiment 49. The method according to any one of Embodiments 1 to 48, further comprising removing at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of water from the first product stream.

[0155] Embodiment 50. The method according to any one of Embodiments 1 to 49, wherein the first product stream contains one or more light hydrocarbons (e.g., methane, ethane, propane).

[0156] Embodiment 51. The method according to Embodiment 50, further comprising separating at least a portion of one or more light hydrocarbons from the first product stream to provide a light hydrocarbon stream.

[0157] Embodiment 52. The method according to any one of Embodiments 1 to 51, further comprising exchanging heat between at least a portion of the first product stream and at least a portion of the first feed stream, thereby cooling at least a portion of the first product stream and heating at least a portion of the first feed stream.

[0158] Embodiment 53. The method according to any one of Embodiments 1 to 52, further comprising exchanging heat between at least a portion of the first product stream and a steam generation zone, thereby cooling at least a portion of the first product stream and supplying heat to the steam generation zone.

[0159] Embodiment 54. The method according to Embodiment 53, further comprising generating steam from the heat supplied to the steam generation zone and generating electricity from the steam.

[0160] Embodiment 55. The method according to Embodiment 53 or 54, wherein the steam is used to heat the first feed stream and / or the second feed stream.

[0161] Embodiment 56. The method according to any one of Embodiments 1 to 55, wherein at least 25%, for example, at least 50%, at least 75%, or at least 90% of the CO in the first product stream is contained in the second feed stream.

[0162] Embodiment 57. The method according to any one of Embodiments 1 to 56, wherein the CO is provided to the second feed stream from a CO source other than the first product stream.

[0163] Embodiment 58. The method according to any one of Embodiments 1 to 57, wherein the first product stream contains H2 and the second feed stream contains at least a part of the H2 in the first product stream.

[0164] Embodiment 59. The method according to any one of Embodiments 1 to 58, wherein at least 25%, for example, at least 50%, at least 75%, or at least 90% of the H2 in the first product stream is contained in the second feed stream.

[0165] Embodiment 60. The method according to any one of Embodiments 1 to 59, wherein the H2 is provided to the second feed stream from a hydrogen source other than the first product stream.

[0166] Embodiment 61. The method according to any one of Embodiments 1 to 60, wherein the second feed stream contains at least a part of the CO2 in the first product stream.

[0167] Embodiment 62. The method according to any one of Embodiments 1 to 61, wherein at least 10%, for example, at least 25%, at least 50%, at least 75%, or at least 90% of the CO2 in the first product stream is contained in the second feed stream.

[0168] Embodiment 63. The method according to any one of Embodiments 1 to 61, wherein the second feed stream does not contain a substantial amount of the CO2 in the first product stream.

[0169] Embodiment 64. The method according to any one of Embodiments 1 to 63, wherein a part of the first product stream included in the second feed stream has an H2:CO ratio in the range of 0.5:1 to 10:1, for example, in the range of 1:1 to 3:1.

[0170] Embodiment 65. The method according to any one of Embodiments 1 to 64, wherein a part of the first product stream included in the second feed stream has a water content of 10 mol% or less, for example, 2 mol% or less, or 0.5 mol% or less.

[0171] Embodiment 66. The method according to any one of Embodiments 1 to 65, wherein a part of the first product stream included in the second feed stream has a CO2 content in the range of 10 to 95 mol% of CO2, for example, 10 to 90 mol%, or 10 to 85 mol%, or 10 to 80 mol%, or 10 to 75 mol%, or 10 to 70 mol%, or 20 to 95 mol%, or 20 to 90 mol%, or 20 to 85 mol%, or 20 to 80 mol%, or 20 to 70 mol%, or 30 to 95 mol%, or 30 to 90 mol%, or 30 to 85 mol%, or 30 to 80 mol%, or 30 to 75 mol%, or 30 to 70 mol% of CO2.

[0172] Embodiment 67. The method according to any one of Embodiments 1 to 66, wherein the second feed stream has an H2:CO ratio in the range of 0.5:1 to 6:1.

[0173] Embodiment 68. The method according to any one of Embodiments 1 to 66, wherein the second feed stream has an H2:CO ratio in the range of 1:1 to 3:1, for example, 1:1 to 2.5:1.

[0174] Embodiment 69. The method according to any one of Embodiments 1 to 66, wherein the second feed stream has an H2:CO ratio of at least 1.4:1, for example, in the range of 1.4:1 to 3:1, or 1.4:1 to 2.5:1.

[0175] Embodiment 70. The method according to any one of Embodiments 1 to 69, wherein the second feed stream contains one or more inert substances of 80% or less, for example, 70 mol% or less, 60 mol% or less, or 50 mol% or less, or 15 to 70 mol%, or 30 to 70 mol%, or 15 to 60 mol%, or 30 to 60 mol%, or 15 to 50 mol%, or 30 to 50 mol%.

[0176] Embodiment 71. The method according to any one of Embodiments 1 to 69, wherein the second feed stream contains up to 80%, for example, up to 70 mol%, up to 60 mol%, or up to 50 mol%, or 15 to 70 mol%, or 30 to 70 mol%, or 15 to 60 mol%, or 30 to 60 mol%, or 15 to 50 mol%, or 30 to 50 mol% of one or more inert substances selected from CO2, methane, and nitrogen.

[0177] Embodiment 72. The method according to any one of Embodiments 1 to 71, wherein the second feed stream contains up to 80%, for example, up to 70 mol%, up to 60 mol%, or up to 50 mol%, or 15 to 70 mol%, or 30 to 70 mol%, or 15 to 60 mol%, or 30 to 60 mol%, or 15 to 50 mol%, or 30 to 50 mol% of CO2.

[0178] Embodiment 73. The method according to any one of Embodiments 1 to 72, wherein the second feed stream has a water content of 10 mol% or less, for example, or 2 mol% or less, or 0.5 mol% or less.

[0179] Embodiment 74. The method according to any one of Embodiments 1 to 73, wherein the Fischer-Tropsch catalyst contains cobalt, iron, rhodium, ruthenium, or a combination thereof.

[0180] Embodiment 75. The method according to any one of Embodiments 1 to 73, wherein the Fischer-Tropsch catalyst contains cobalt in an amount in the range of 5 to 25% by weight, for example, calculated as Co(0), 7 to 25% by weight, or 10 to 25% by weight, or 5 to 20% by weight, or 7 to 20% by weight, or 10 to 20% by weight.

[0181] Embodiment 76. The method according to any one of Embodiments 1 to 74, wherein the Fischer-Tropsch catalyst contains iron in an amount in the range of 5 to 95% by weight, for example, 10 to 95% by weight, or 25 to 95% by weight, or 50 to 95% by weight, or 5 to 85% by weight, or 10 to 85% by weight, or 25 to 85% by weight, or 50 to 85% by weight, or 5 to 75% by weight, or 10 to 75% by weight, or 25 to 75% by weight, calculated as Fe(0).

[0182] Embodiment 77. The method according to any one of Embodiments 74 to 76, wherein the Fischer-Tropsch catalyst further contains manganese.

[0183] Embodiment 78. The method according to Embodiment 77, wherein manganese is present in an amount up to 15% by weight, for example, up to 12% by weight, or up to 10% by weight, or up to 7% by weight, or in the range of 0.1 to 15% by weight, for example, 0.1 to 10% by weight, or 0.1 to 5% by weight, 0.5 to 15% by weight, or 0.5 to 10% by weight, or 0.5 to 5% by weight, calculated as Mn(0).

[0184] Embodiment 79. The method according to any one of Embodiments 1 to 78, wherein the Fischer-Tropsch catalyst is a supported catalyst, and the carrier contains at least one of titanium oxide, zirconium oxide, cerium oxide, aluminum oxide, silicon oxide, and zinc oxide.

[0185] Embodiment 80. The method according to any one of Embodiments 1 to 78, wherein the Fischer-Tropsch catalyst is a supported catalyst, and the carrier contains at least one of titanium oxide, aluminum oxide, and silicon oxide.

[0186] Embodiment 81. The method according to any one of Embodiments 1 to 78, wherein the Fischer-Tropsch catalyst is a supported catalyst, and the carrier is a titanium dioxide carrier.

[0187] Embodiment 82. The method according to any one of Embodiments 1 to 81, wherein the Fischer-Tropsch catalyst is activated by contact with a reducing gas, such as hydrogen.

[0188] Embodiment 83. The method according to Embodiment 80, wherein the reducing gas contains at least a part of hydrogen from the first product stream.

[0189] Embodiment 84. The method according to any one of Embodiments 1 to 81, wherein the Fischer-Tropsch catalyst is activated by contact with H2 and CO.

[0190] Embodiment 85. The method according to Embodiment 84, wherein the reducing gas contains at least a part of H2 and CO from the first product stream.

[0191] Embodiment 86. The method according to any one of Embodiments 82 to 84, wherein the activation is carried out at a temperature in the range of 200 to 400 °C.

[0192] Embodiment 87. The method according to any one of Embodiments 1 to 86, wherein the second temperature is in the range of 150 to 400 °C (for example, in the range of 150 to 350 °C, or 150 to 300 °C, or 150 to 250 °C, or 150 to 200 °C, or 200 to 400 °C, or 200 to 350 °C, or 200 to 300 °C, or 200 to 250 °C, or 250 to 400 °C, or 250 to 350 °C, or 250 to 300 °C, or 300 to 400 °C).

[0193] Embodiment 88. The method according to any one of Embodiments 1 to 87, wherein the second temperature is in the range of 200 to 350 °C.

[0194] Embodiment 89. The method according to any one of Embodiments 1 to 88, wherein the first temperature is within 100 °C of the second temperature, for example, within 50 °C of the second temperature, or within 25 °C of the second temperature.

[0195] Embodiment 90. The method according to any one of Embodiments 1 to 89, wherein the first temperature is at least 100 °C higher than the second temperature, for example, at least 150 °C higher than the second temperature, or at least 200 °C higher than the second temperature.

[0196] Embodiment 91. The method according to any one of Embodiments 1 to 90, wherein the second pressure ranges from 10 to 50 barg (for example, 20 to 50 barg, or 25 to 50 barg, or 10 to 40 barg, or 20 to 40 barg, or 25 to 40 barg, or 10 to 35 barg, or 20 to 35 barg, or 25 to 35 barg).

[0197] Embodiment 92. The method according to any one of Embodiments 1 to 91, wherein the second pressure ranges from 20 to 50 barg.

[0198] Embodiment 93. The method according to any one of Embodiments 1 to 92, wherein the Fischer-Tropsch reaction is carried out at a GHSV in the range of 1,000 to 2,000,000 h-1 (for example, 1,000 to 1,200,000 h-1, or 1,000 to 500,000 h-1, or 1,000 to 100,000 h-1, or 5,000 to 1,200,000 h-1, or 5,000 to 500,000 h-1, or 5,000 to 100,000 h-1, or 10,000 to 1,200,000 h-1, or 10,000 to 500,000 h-1, or 10,000 to 100,000 h-1).

[0199] Embodiment 94. The method according to any one of Embodiments 1 to 93, wherein contacting the Fischer-Tropsch catalyst with the second feed stream to obtain the second product stream is carried out at a C5+ selectivity of at least 30%, for example, at least 50%, or at least 70%.

[0200] Embodiment 95. The method according to any one of Embodiments 1 to 94, wherein contacting the Fischer-Tropsch catalyst with a second feed stream to obtain a second product stream is carried out with a selectivity for C5+ alkanes of at least 30%, for example at least 50%, or at least 70%.

[0201] Embodiment 96. The method according to any one of Embodiments 1 to 95, wherein contacting the Fischer-Tropsch catalyst with a second feed stream to provide a second product stream is carried out with a selectivity for C5+ alkanes and C5+ alcohols of at least 30%, for example at least 50%, or at least 70%.

[0202] Embodiment 97. The method according to any one of Embodiments 1 to 96, further comprising separating at least a portion of water from the second product stream.

[0203] Embodiment 98. The method according to any one of Embodiments 1 to 97, further comprising separating at least a portion of C1-C4 hydrocarbons from the second product stream to provide a light hydrocarbon stream.

[0204] Embodiment 99. The method according to Embodiment 98, further comprising including at least a portion of the light hydrocarbon stream in the first feed stream and / or the second feed stream.

[0205] Embodiment 100. The method according to Embodiment 98 or Embodiment 99, further comprising oxidizing at least a portion of the light hydrocarbon stream to provide a pOX stream containing CO and / or CO2, and including at least a portion of the pOX stream in the first feed stream and / or the second stream.

[0206] Embodiment 101. The method according to any one of Embodiments 98 to 100, further comprising reforming (e.g., steam reforming and / or autothermal reforming) at least a portion of the light hydrocarbon stream to provide a reformed stream containing CO and / or CO2, and including at least a portion of the reformed stream in the first feed stream and / or the second feed stream.

[0207] Embodiment 102. The method according to embodiment 100 or 101, wherein the oxidation or reforming provides energy, thermal energy, or electrical energy.

[0208] Embodiment 103. The method according to any one of embodiments 98 - 102, further comprising burning at least a portion of the light hydrocarbon stream to provide energy, such as thermal energy or electrical energy.

[0209] Embodiment 104. The method according to embodiment 102 or 103, wherein thermal energy is provided and the thermal energy is used to heat the first feed stream.

[0210] Embodiment 105. The method according to any one of embodiments 1 - 104, further comprising exchanging heat between at least a portion of the second product stream and a steam generation zone, thereby cooling at least a portion of the first feed stream and providing heat to the steam generation zone.

[0211] Embodiment 106. The method according to embodiment 105, further comprising generating steam from the heat provided to the steam generation zone and generating electricity from the steam.

[0212] Embodiment 107. The method according to embodiment 105 or 106, wherein the steam is used to heat the first feed stream and / or the second feed stream.

[0213] Embodiment 108. The method according to any one of embodiments 1 - 107, further comprising exchanging heat between at least a portion of the second product stream and at least a portion of the second feed stream, thereby cooling at least a portion of the second product stream and heating at least a portion of the second feed stream.

[0214] Embodiment 109. The method according to any one of embodiments 1 - 108, further comprising recycling at least a portion of the H2 of the second product stream to the second feed stream.

[0215] Embodiment 110. The method according to any one of Embodiments 1 to 109, further comprising recycling at least a part of the H2 in the second product stream to the first feed stream.

[0216] Embodiment 111. The method according to Embodiment 110, further comprising providing H2 from an H2 source other than the first product stream to the second feed stream.

[0217] Embodiment 112. The method according to Embodiment 111, where the H2 from the second product stream constitutes a majority of the H2 in the first feed stream, for example, at least 90%, at least 95%, or at least 98% of the H2 in the first feed stream.

[0218] Embodiment 113. The method according to any one of Embodiments 1 to 112, further comprising recycling at least a part of the CO in the second product stream to the second feed stream.

[0219] Embodiment 114. The method according to any one of Embodiments 1 to 113, further comprising recycling at least a part of the CO in the second product stream to the first feed stream.

[0220] Embodiment 115. The method according to any one of Embodiments 1 to 114, further comprising recycling at least a part of the inert substances in the second product stream to the second feed stream.

[0221] Embodiment 116. The method according to any one of Embodiments 1 to 115, further comprising recycling at least a part of the inert substances in the second product stream to the first feed stream.

[0222] Embodiment 117. The method according to any one of Embodiments 1 to 116, further comprising recycling at least a part of the CO2 in the second product stream to the first feed stream.

[0223] The method according to embodiment 117, further comprising providing CO2 from a CO2 source other than the first product stream to the second feed stream.

[0224] Embodiment 119. The method according to embodiment 118, wherein the CO2 from the second product stream constitutes a majority of the CO2 in the first feed stream, for example, at least 90%, at least 95%, or at least 98% of the CO2 in the first product stream.

[0225] Embodiment 120. The method according to any one of embodiments 1 to 119, wherein one or more products are provided from at least a portion of the C5+ hydrocarbons in the second product stream.

[0226] Embodiment 121. The method according to embodiment 120, wherein one or more products include fuels (e.g., gasoline, diesel fuel, aviation fuel), lubricants, and waxes.

[0227] Embodiment 122. The method according to any one of embodiments 1 to 121, further comprising hydrotreating at least a portion of the C5+ hydrocarbons in the second product stream.

[0228] Embodiment 123. The method according to any one of embodiments 1 to 122, wherein at least a portion of the CO2 in the first feed stream and / or the second feed stream is from a renewable source.

[0229] Embodiment 124. The method according to any one of embodiments 1 to 123, wherein at least a portion of the CO2 in the first feed stream and / or the second feed stream is from direct air capture.

[0230] Embodiment 125. The method according to any one of embodiments 1 to 124, wherein at least a portion of the CO2 in the first feed stream and / or the second feed stream is captured from a manufacturing plant, such as a bioethanol plant, a steel mill, or a cement factory.

[0231] Method according to any one of Embodiments 1 to 125, wherein at least a part of the H2 in the first feed stream or the second feed stream is from a renewable source.

[0232] Method according to any one of Embodiments 1 to 126, wherein at least a part of the hydrogen in the first feed stream or the second feed stream is green hydrogen.

[0233] Method according to any one of Embodiments 1 to 127, wherein at least a part of the hydrogen in the first feed stream or the second feed stream is blue hydrogen.

[0234] Method according to any one of Embodiments 1 to 128, wherein at least a part of the hydrogen in the first feed stream or the second feed stream is grey hydrogen, black hydrogen, brown hydrogen, pink hydrogen, turquoise hydrogen, yellow hydrogen, and / or white hydrogen.

[0235] Method according to any one of Embodiments 1 to 129, further comprising providing at least a part of the H2 to the first feed stream and / or the second feed stream by electrolysis of water.

[0236] Method according to Embodiment 130, wherein the electrolysis of water is carried out using at least partially electricity from renewable resources.

[0237] Method according to Embodiment 130 or Embodiment 131, wherein the electrolysis of water is carried out using at least partially electricity generated from heat exchange from the first product stream and / or the second product stream or from steam generated by burning a light hydrocarbon stream.

[0238] Method according to any one of Embodiments 130 to 132, further comprising providing at least a part of the O2 generated in the electrolysis for partial oxidation.

[0239] Embodiment 134. The method according to any one of Embodiments 1 to 133, wherein the method is carried out in a reactor system including a first reactor in which a reverse water gas shift catalyst is disposed and a second reactor in which a Fischer-Tropsch catalyst is disposed.

[0240] Embodiment 135. The method according to any one of Embodiments 1 to 134, wherein the method is carried out in a reactor system including a first catalyst bed in which a reverse water gas shift catalyst is disposed, and the second reaction zone includes a second catalyst bed in which a Fischer-Tropsch catalyst is disposed.

[0241] Embodiment 136. The method according to Embodiment 135, wherein the first reactor bed and the second reactor bed are disposed in the same reactor.

[0242] Embodiment 137. The method according to any one of Embodiments 1 to 133, wherein the method is carried out in a reactor system including one or more first catalyst containers in which a reverse water gas shift catalyst is disposed, and the second reaction zone includes one or more second catalyst containers in which a Fischer-Tropsch catalyst is disposed.

[0243] Embodiment 138. The method according to Embodiment 137, wherein the one or more first catalyst containers and the one or more second catalyst containers are disposed in the same reactor.

[0244] Embodiment 139. The method according to any one of Embodiments 1 to 138, wherein the method is carried out in a reactor system including a reactor in which a reverse water gas shift catalyst and a Fischer-Tropsch catalyst are disposed, for example, in a mixture.

[0245] The details presented herein are for illustrative purposes only, for the purpose of exemplarily considering the preferred embodiments of the present invention, and are provided to offer what is considered to be the most useful and readily understandable explanation of the principles and conceptual aspects of the various embodiments of the present invention. In this regard, no attempt is made to show the structural details of the present invention in more detail than is necessary for a basic understanding of the present invention, and the description made together with the drawings and / or examples will clarify to those skilled in the art how some forms of the present invention can actually be embodied. Therefore, before the disclosed methods and devices are described, it should be understood that the aspects described herein are not limited to specific embodiments, devices, or configurations, and thus, of course, can vary. It should also be understood that the terms used herein are for the sole purpose of describing a particular aspect and are not intended to be limiting unless specifically defined herein.

[0246] The terms "a", "an", "the", and similar referents used in the context of describing the present invention (in particular, the context of the following claims) should be construed to include both the singular and the plural unless otherwise indicated herein or clearly contradicted by the context. The recitation of a range of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within that range. Unless specifically indicated herein, each individual value is incorporated herein as if it were individually recited herein. Furthermore, it will be understood that the endpoints of each range are significant both in relation to the other endpoint and independently of the other endpoint.

[0247] All methods described in this specification can be performed in any suitable order of steps, unless otherwise indicated herein or clearly inconsistent with the context. Any and all examples provided herein, or the use of exemplary language (e.g., "such as"), are merely intended to clarify the invention better and do not limit the scope of the invention as otherwise claimed. No language in this specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0248] Throughout this specification and the claims, unless the context clearly requires otherwise, words such as "comprise", "comprising", etc. shall be construed in an inclusive sense, i.e., in the sense of "including, but not limited to", rather than in an exclusive or exhaustive sense. Words using the singular or plural number shall also include the plural and the singular respectively. Further, the words "herein", "above", and "below", and words of similar import, when used in this application, refer to the whole of this application and not to any particular part of this application.

[0249] As will be understood by those skilled in the art, each embodiment disclosed in this specification can include, consist essentially of, or consist of its specific recited elements, steps, components, or constituents. As used herein, the transitional phrase "comprise" or "comprises" means including, but not limited to, and allows the inclusion of elements, steps, components, or constituents not specifically recited, even in large quantities. The transitional phrase "consisting of" excludes any element, step, component, or constituent not specifically recited. The transitional phrase "consisting essentially of" limits the scope of an embodiment to the specific elements, steps, components, or constituents, and those that do not materially affect the embodiment.

[0250] Unless otherwise indicated, the numerical parameters set forth in the specification and claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the claims, each numerical parameter should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0251] Numerical ranges and parameters setting forth the broad scope of the invention disclosed herein are approximations, however, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0252] The grouping of alternative elements or embodiments of the invention disclosed herein should not be construed as a limitation. Members of each group may be referred to individually, or in any combination with other members of the group or other elements found herein, and may be claimed. It is anticipated that one or more members of a group may be included in, or deleted from, the group for convenience and / or for reasons of patentability. Any such inclusion or deletion shall occur, the specification is considered to include the modified group and thus to satisfy the written description of all Markush groups used in the appended claims.

[0253] Some embodiments of the present invention are described herein, including the best mode known to the inventors for carrying out the present invention. Of course, variations of these described embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventors expect those skilled in the art to appropriately use such variations, and the inventors intend for the present invention to be practiced in a manner different from that specifically described herein. Accordingly, the present invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Further, unless otherwise indicated herein or clearly contradicted by context, any combination of the above elements in all possible variations thereof is included by the present invention.

[0254] Throughout this specification, numerous references are made to patents and printed publications. Each of the cited references and printed publications is hereby incorporated by reference in its entirety into this specification.

[0255] Furthermore, it should be understood that the embodiments of the present invention disclosed herein are illustrative of the principles of the present invention. Other modifications that may be used are within the scope of the present invention. Accordingly, by way of example and not limitation, alternative configurations of the present invention may be utilized in accordance with the teachings herein. Accordingly, the present invention is not strictly limited to that which is shown and described.

Claims

**Claim 1** A method for performing an integrated Fischer - Tropsch process, comprising: providing a first feed stream comprising H2 and CO2; contacting a first feed stream with a reverse water - gas shift catalyst at a first temperature in the range of 200 - 900 °C and a first pressure to perform a reverse water - gas shift reaction, thereby providing a first product stream comprising CO and H2, wherein the first product stream has a lower CO2 concentration and a higher CO concentration than the first feed stream; contacting a Fischer - Tropsch catalyst with a second feed stream comprising H2 and at least a portion of the CO of the first product stream at a second temperature and a second pressure to provide a second product stream comprising C5+ hydrocarbons. **Claim 2** The method according to claim 1, wherein the molar ratio of H2 to CO2 in the first feed stream is in the range of 0.5:1 to 10:

1. **Claim 3** The method according to claim 1, wherein the reverse water - gas shift reaction has a CO selectivity of at least 95%. **Claim 4** The method according to claim 1, wherein the reverse water - gas shift reaction has a methane selectivity of 2% or less. **Claim 5** The method according to claim 1, wherein the reverse water - gas shift reaction has a CO2 conversion rate of at least 30%. **Claim 6** The method according to claim 1, wherein the reverse water - gas shift reaction has a CO2 conversion rate of 80% or less. **Claim 7** The method according to claim 1, wherein the reverse water - gas shift reaction is carried out at a temperature in the range of 400 - 700 °C. **Claim 8** The method according to claim 1, further comprising activating the reverse water - gas shift catalyst with a reducing stream comprising a reducing gas. **Claim 9** The method according to claim 1, wherein the first product stream comprises 75 mol% or less of CO2. **Claim 10** The method according to claim 1, wherein the first product stream comprises 5 mol% or less of methane. **Claim 11** The method according to claim 1, further comprising separating the first product stream and recycling at least a portion of the CO2 or H2 of the first product stream to the first feed stream. **Claim 12** The method according to claim 1, further comprising cooling at least a portion of the first product stream and heating at least a portion of the first feed stream by heat exchange between at least a portion of the first product stream and at least a portion of the first feed stream. **Claim 13** The method according to claim 1, wherein at least 25% of the CO of the first product stream is included in the second feed stream. **Claim 14** The method according to claim 1, wherein the first product stream comprises H2 and at least 25% of the H2 of the first product stream is included in the second feed stream. **Claim 15** The method according to claim 1, wherein at least 10% of the CO2 in the first product stream is included in the second feed stream.

16. The method according to claim 1, wherein the second feed stream contains substantially no CO2 from the first product stream.

17. The method according to claim 1, wherein the second feed stream has an H2:CO ratio in the range of 0.5:1 to 6:

1.

18. The method according to claim 1, wherein the Fischer-Tropsch catalyst comprises cobalt, iron, rhodium, ruthenium, or a combination thereof.

19. The method according to claim 18, wherein the Fischer-Tropsch catalyst further comprises manganese.

20. The method according to claim 1, wherein the Fischer-Tropsch catalyst is activated by contact with a reducing gas containing at least a portion of the hydrogen from the first product stream.

21. The method according to claim 1, wherein the second temperature is in the range of 200 to 350 °C.

22. The method according to claim 1, wherein the first temperature is at least 100 °C higher than the second temperature.

23. The method according to claim 1, wherein forming the second product stream by contacting the Fischer-Tropsch catalyst with the second feed stream is carried out with a selectivity of at least 30% for C5+ alkanes.

24. The method according to claim 1, further comprising separating at least a portion of the C1-C4 hydrocarbons from the second product stream to form a light hydrocarbon stream.

25. The method according to claim 24, further comprising including at least a portion of the light hydrocarbon stream in the first feed stream and / or the second feed stream.

26. The method according to claim 24, further comprising oxidizing at least a portion of the light hydrocarbon stream to form a pOX stream containing CO and / or CO2, and further including at least a portion of the pOX stream in the first feed stream and / or the second stream.

27. The method according to claim 24, further comprising burning at least a portion of the light hydrocarbon stream to provide thermal energy, and the thermal energy is used to heat the first feed stream.

28. The method according to claim 1, further comprising cooling at least a portion of the second product stream by heat exchange between at least a portion of the second product stream and at least a portion of the second feed stream, and heating at least a portion of the second feed stream.

29. The method according to claim 1, further comprising recycling at least a portion of the H2 in the second product stream to the second feed stream.

30. The method according to claim 1, further comprising recycling at least a portion of the H2 in the second product stream to the first feed stream, wherein the H2 from the second product stream constitutes at least 90% of the H2 in the first feed stream.

31. The method according to claim 1, further comprising recycling at least a portion of the CO in the second product stream to the second feed stream or the first feed stream.

32. The method according to claim 1, further comprising recycling at least a portion of the CO2 in the second product stream to the first feed stream, wherein the CO2 from the second product stream constitutes at least 90% of the CO2 in the first feed stream.

33. The method according to claim 1, carried out in a reactor system comprising a first reactor in which a reverse water gas shift catalyst is disposed and a second reactor in which the Fischer-Tropsch catalyst is disposed.

34. The method according to claim 1, implemented in a reactor system comprising a first catalyst bed in which a reverse water gas shift catalyst is disposed and a second catalyst bed in which the Fischer-Tropsch catalyst is disposed, wherein the first reactor bed and the second reactor bed are disposed in the same reactor.

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