Palladium, Platinum, and Gold Catalysts for Reverse Water Gas Shift and Integrated Fischer-Tropsch Processes

Abstract

The present disclosure generally relates to reverse water gas shift processes, integrated Fischer-Tropsch processes, and supported reverse water gas shift catalysts for carrying out these processes. The catalysts described herein include a support that is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support containing a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; at least one of platinum, palladium, and gold present in an amount ranging from 0.05 to 10 wt.% of the catalyst based on the total weight of the catalyst; and manganese present in an amount ranging from 0.5 to 20 wt.% of the catalyst based on the total weight of the catalyst.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority from International Patent Application Nos. PCT / CN2022 / 102685 (filed June 30, 2022), PCT / CN2022 / 102763 (filed June 30, 2022), PCT / CN2022 / 102976 (filed June 30, 2022), and PCT / CN2022 / 102812 (filed June 30, 2022), each of which is incorporated herein by reference in its entirety. [Technical Field]

[0002] The present disclosure generally relates to reverse water gas shift catalysts, methods for making the same, and methods for performing a reverse water gas shift reaction. The present disclosure also relates to integrating a process for performing a reverse water gas shift reaction with a process for performing a Fischer-Tropsch reaction. [Background technology]

[0003] The reverse water gas shift reaction (rWGS) is a favorable route to obtain 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] However, the rWGS reaction is not favored in all situations. For example, a competing reaction is the Sabatier reaction (Equation (3)), which reduces carbon monoxide yield in favor of methane production, which is not an active feedstock for FT.

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[0005] Similarly, the carbon monoxide product from rWGS can be hydrogenated to methane, as shown in equation (4).

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[0006] Coupled with equations (3) and (4), additional undesirable side reactions can occur. These side reactions can form undesirable carbon deposits on the surface of the catalyst used to promote rWGS. Examples of these carbon-producing side reactions are shown in equations (5), (6), and (7). All three of these reactions are endothermic and, like the rWGS reaction, are favored at higher temperatures.

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[0007] Given the multiple reactions and competing thermodynamics at play, there remains a need in the art for new rWGS catalysts and methods, particularly for integration with the Fischer-Tropsch process. Summary of the Invention

[0008] In one aspect, the present disclosure provides a supported reverse water gas shift catalyst, the catalyst comprising: a support which is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support comprising a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; at least one of platinum, palladium, and gold present in an amount ranging from 0.05 to 10 weight percent of the catalyst, based on the total weight of the catalyst; and and manganese present in an amount ranging from 0.5 to 20 weight percent of the catalyst, based on the total weight of the catalyst.

[0009] In another aspect, the present disclosure provides a method of making the catalyst described herein, the method comprising: providing a support which is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium support, or a mixed oxide support comprising a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; contacting the support with a liquid comprising one or more platinum, palladium, or gold-containing compounds and one or more manganese-containing compounds dispersed in a solvent; evaporating the solvent to form a catalyst precursor; and calcining said catalyst precursor.

[0010] In another aspect, the present disclosure provides a catalyst described herein made by a method described herein.

[0011] In another aspect, the present disclosure provides a method for conducting a reverse water gas shift reaction, the method comprising contacting a catalyst described herein with a feed stream comprising CO and H at a temperature in the range of 200 to 900° C. to form a product stream comprising CO and H, wherein the product stream has a lower concentration of CO and a higher concentration of CO than the feed stream.

[0012] In one aspect, the present disclosure provides a process for conducting an integrated Fischer-Tropsch process, the process comprising: forming a first feed stream comprising H2 and CO2; contacting the 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 conduct a reverse water gas shift reaction and 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 H and at least a portion of the CO of said first product stream at a second temperature and a second pressure to form a second product stream comprising C5+ hydrocarbons; The reverse water gas shift catalyst is a supported reverse water gas shift catalyst, a support which is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support comprising a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; At least one of platinum, palladium, and gold present in an amount ranging from 0.05 to 10 weight percent of the catalyst, based on the total weight of the catalyst; and and manganese present in an amount ranging from 0.5 to 20% by weight of the catalyst, based on the total weight of the catalyst.

[0013] The accompanying drawings are included to provide a further understanding of the methods of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings are not necessarily to scale, and sizes of various elements may be distorted for clarity. The drawings illustrate one or more embodiments of the present disclosure and, together with the description, serve to explain the principles and operation of the present disclosure. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram of the reverse water gas shift reaction described herein. [Figure 2] Figure 2 is a schematic diagram of a method for carrying out the integrated Fischer-Tropsch process described herein. [Figure 3] Figure 3 is a schematic diagram of a method for carrying out the integrated Fischer-Tropsch process described herein. [Figure 4] Figure 4 is a schematic diagram of a method for carrying out the integrated Fischer-Tropsch process described herein. [Figure 5] Figure 5 is a schematic diagram of a method for carrying out the integrated Fischer-Tropsch process described herein. [Figure 6] Figure 6 is a schematic diagram of a method for carrying out the integrated Fischer-Tropsch process described herein. [Figure 7] Figure 7 is a schematic diagram of a method for carrying out the integrated Fischer-Tropsch process described herein. [Figure 8] FIG. 8 is a graph of carbon dioxide conversion for an rWGS catalyst as described herein. [Figure 9] FIG. 9 is a graph of the carbon molar selectivity to methane for the rWGS catalysts described herein. [Figure 10] FIG. 10 is a graph of carbon dioxide conversion for a rWGS catalyst as described herein. [Figure 11] FIG. 11 is a graph of the carbon molar selectivity to methane for the rWGS catalysts described herein. [Figure 12] FIG. 12 is a graph of carbon dioxide conversion for an rWGS catalyst as described herein. [Figure 13] FIG. 13 is a graph of the carbon molar selectivity to methane for the rWGS catalysts described herein. DETAILED DESCRIPTION OF THE INVENTION

[0015] As mentioned above, the reverse water-gas shift reaction (rWGS) is useful for reacting carbon dioxide with hydrogen to produce carbon monoxide and water, providing a carbon monoxide- and hydrogen-containing feedstock, often referred to as "syngas," for use in processes such as the Fischer-Tropsch process. However, the Sabatier reaction, carbon monoxide methanation, and carbon-forming side reactions can interfere with the rWGS reaction. While the Sabatier reaction and CO methanation are exothermic and favored at low temperatures, the rWGS and carbon-forming side reactions are endothermic and favored at high temperatures. Therefore, there remains a need for rWGS catalysts that can provide good performance despite these complicating factors. Here, we have provided a supported reverse water-gas shift catalyst containing a metal oxide support, at least one of platinum, palladium, and gold, and manganese, that can meet the requirements for a commercially useful rWGS process. Furthermore, the inventors have discovered that the rWGS process is particularly advantageous for integration with the Fischer-Tropsch process by using a supported reverse water gas shift catalyst containing a metal oxide support, at least one of platinum, palladium, and gold, and manganese.

[0016] Reverse Water Gas Shift Catalyst In one aspect, the present disclosure provides a supported reverse water gas shift catalyst for use in, for example, an rWGS process integrated with an FT process. The supported reverse water gas shift catalyst includes a support that is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support including a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; at least one of platinum, palladium, and gold, present in an amount ranging from 0.05 to 10 wt. % of the catalyst, based on the total weight of the catalyst; and manganese, present in an amount ranging from 0.5 to 20 wt. % of the catalyst, based on the total weight of the catalyst.

[0017] As noted above, the reverse water gas shift catalyst of the present disclosure is a supported catalyst. In various embodiments described elsewhere herein, the support comprises at least 70 wt. % of the catalyst on an oxide basis, e.g., at least 75 wt. %, or 80 wt. %, or 85 wt. %, or 90 wt. %.

[0018] In various embodiments described elsewhere herein, the support is a cerium oxide support. As used herein, a "cerium oxide" support is a support exhibiting at least a surface layer (e.g., 50 microns thick) that is at least 50% cerium oxide by weight, on an oxide basis. In various embodiments of the present disclosure described herein, at least the surface layer of the cerium oxide support comprises at least 60% cerium oxide by weight, e.g., at least 70% cerium oxide by weight, or at least 80% cerium oxide by weight. In some such embodiments, at least the surface layer of the cerium oxide support comprises at least 90% cerium oxide by weight. For example, in some embodiments, at least the surface layer of the cerium oxide support comprises at least 95% cerium oxide by weight or at least 98% cerium oxide by weight. In various examples, the cerium oxide support contains cerium oxide substantially throughout, e.g., at least 50% by weight of the cerium oxide support is cerium oxide, on an oxide basis. For example, in various embodiments, the cerium oxide support comprises at least 60% by weight cerium oxide, e.g., at least 70% by weight cerium oxide, or at least 80% by weight cerium oxide. In various embodiments, the cerium oxide support comprises at least 90% by weight cerium oxide, e.g., at least 95% by weight cerium oxide, or at least 98% by weight cerium oxide. In some embodiments, the cerium oxide support may further comprise an additional metal or metal oxide.

[0019] In various embodiments described elsewhere herein, the support is a titanium oxide support. As used herein, a "titanium oxide" support is a support exhibiting at least a surface layer (e.g., 50 microns thick) that is at least 50% titanium oxide by weight, on an oxide basis. In various embodiments of the present disclosure described herein, at least the surface layer of the titanium oxide support comprises at least 60% titanium oxide by weight, e.g., at least 70% titanium oxide by weight, or at least 80% titanium oxide by weight. In some such embodiments, at least the surface layer of the titanium oxide support comprises at least 90% titanium oxide by weight. For example, in some embodiments, at least the surface layer of the titanium oxide support comprises at least 95% titanium oxide by weight or at least 98% titanium oxide by weight. In various examples, the titanium oxide support contains titanium oxide substantially throughout, e.g., at least 50% titanium oxide by weight, on an oxide basis, of the titanium oxide support. For example, in various embodiments, the titanium oxide support comprises at least 60% titanium oxide by weight, e.g., at least 70% titanium oxide by weight, or at least 80% titanium oxide by weight. In various embodiments, the titanium oxide support comprises at least 90% by weight titanium oxide, e.g., at least 95% by weight titanium oxide, or at least 98% by weight titanium oxide. In some embodiments, the titanium oxide support may further comprise an additional metal or metal oxide.

[0020] In various embodiments described elsewhere herein, the support is an aluminum oxide support. As used herein, an "aluminum oxide" support is a support exhibiting at least a surface layer (e.g., 50 microns thick) that is at least 50% aluminum oxide by weight, on an oxide basis. In various embodiments of the present disclosure described herein, at least the surface layer of the aluminum oxide support comprises at least 60% aluminum oxide by weight, e.g., at least 70% aluminum oxide by weight, or at least 80% aluminum oxide by weight. In some such embodiments, at least the surface layer of the aluminum oxide support comprises at least 90% aluminum oxide by weight. For example, in some embodiments, at least the surface layer of the aluminum oxide support comprises at least 95% aluminum oxide by weight or at least 98% aluminum oxide by weight. In various examples, the aluminum oxide support contains aluminum oxide substantially throughout, e.g., at least 50% aluminum oxide by weight, on an oxide basis, of the aluminum oxide support. For example, in various embodiments, the aluminum oxide support comprises at least 60% aluminum oxide by weight, e.g., at least 70% aluminum oxide by weight, or at least 80% aluminum oxide by weight. In various embodiments, the aluminum oxide support comprises at least 90% by weight aluminum oxide, e.g., at least 95% by weight aluminum oxide, or at least 98% by weight aluminum oxide. In some embodiments, the aluminum oxide support may further comprise an additional metal or metal oxide.

[0021] In various embodiments described elsewhere herein, the support is a zirconium oxide support. As used herein, a "zirconium oxide" support is a support exhibiting at least a surface layer (e.g., 50 microns thick) that is at least 50% by weight zirconium oxide on an oxide basis. In various embodiments of the present disclosure described herein, at least the surface layer of the zirconium oxide support comprises at least 60% by weight zirconium oxide, e.g., at least 70% by weight zirconium oxide, or at least 80% by weight zirconium oxide. In some such embodiments, at least the surface layer of the zirconium oxide support comprises at least 90% by weight zirconium oxide. For example, in some embodiments, at least the surface layer of the zirconium oxide support comprises at least 95% by weight zirconium oxide or at least 98% by weight zirconium oxide. In various examples, the zirconium oxide support contains zirconium oxide substantially throughout, e.g., at least 50% by weight of the zirconium oxide support is zirconium oxide on an oxide basis. For example, in various embodiments, the zirconium oxide support comprises at least 60 wt. % zirconium oxide, e.g., at least 70 wt. % zirconium oxide, or at least 80 wt. % zirconium oxide. In various embodiments, the zirconium oxide support comprises at least 90 wt. % zirconium oxide, e.g., at least 95 wt. % zirconium oxide, or at least 98 wt. % zirconium oxide. In some embodiments, the zirconium oxide support may further comprise an additional metal or metal oxide.

[0022] In various embodiments described elsewhere herein, the support is a mixed oxide support. These can be provided, for example, by forming a support containing a mixture of the above oxides, or both. For example, in some embodiments, the mixed oxide support is a mixture of two or more metal oxides, such as cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide. In some embodiments, at least the surface layer of the support comprises, on an oxide basis, at least 50% by weight of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide in total. In some embodiments, at least the surface layer of the mixed oxide support comprises at least 60% by weight, e.g., at least 70% by weight, or at least 80% by weight of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide in total. In some embodiments, at least the surface layer of the mixed oxide support comprises at least 90% by weight, e.g., at least 95% by weight, or at least 98% by weight of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide. In various examples, the mixed oxide support contains oxides substantially throughout, e.g., at least 50 wt.% of the mixed oxide support is two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide. In various embodiments, the mixed oxide support comprises a total of at least 60 wt.%, e.g., at least 70 wt.%, or at least 80 wt.%, of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide. In various embodiments, the mixed oxide support comprises a total of at least 90 wt.%, e.g., at least 95 wt.%, or at least 98 wt.%, of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide. In some embodiments, the mixed oxide support may further comprise an additional metal or metal oxide.

[0023] The inventors have found that cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide can provide good performance when there are no substantial amounts of other metals present in the support. For example, in various embodiments of the present disclosure described elsewhere herein, the support does not contain additional metals in a total amount of more than 2 wt. %, e.g., more than 1 wt. %, or more than 0.5 wt. % additional metals, on an oxide basis.

[0024] However, the inventors have noted that in many cases, performance can be desirably affected by including other metals in the support. Accordingly, in other embodiments described elsewhere herein, the support includes at least one additional metal. In various embodiments, the total amount of the at least one additional metal, on an oxide basis, ranges from 0.5 to 20 wt %, e.g., 1 to 20 wt %, or 2 to 20 wt %, or 0.5 to 15 wt %, or 1 to 15 wt %, or 2 to 15 wt %, or 0.5 to 10 wt %, or 1 to 10 wt %, or 2 to 10 wt %, or 0.5 to 5 wt %, or 1 to 5 wt %.

[0025] Supports suitable for use herein can have a range of pore volumes. One of skill in the art will select an appropriate pore volume for the desired catalytic process. For example, in various embodiments described elsewhere herein, the pore volume is at least 0.05 mL / g, e.g., at least 0.1 mL / g. In various embodiments described elsewhere herein, the pore volume is at most 1.5 mL / g, e.g., at most 1 mL / g. In various embodiments of the present disclosure described herein, the pore volume ranges from 0.05 to 1.5 mL / g, e.g., from 0.1 mL / g to 1 mL / g. Pore volume is measured by mercury porosimetry, for example, as measured according to ASTM D4284-12.

[0026] As described above, the supported reverse water gas shift catalyst of the present disclosure includes at least one of platinum, palladium, and gold. For example, in various embodiments described elsewhere herein, platinum is present in the catalyst. For purposes of this disclosure, the amount of platinum present is calculated as the weight percent of platinum atoms in the catalyst based on the total weight of the catalyst, regardless of the form in which the platinum may be present. Platinum may be present in the catalyst in various forms; most commonly, platinum is present primarily as a metal, a metal oxide, or a combination thereof. In some embodiments of the present disclosure described herein, platinum is present in the catalyst in an amount ranging from 0.05 to 10 wt %, e.g., from 0.1 to 10 wt %, or from 0.5 to 10 wt %, or from 1 to 10 wt %, or from 2 to 10 wt %, or from 5 to 10 wt %, based on the total weight of the catalyst. For example, in some embodiments, platinum is present in the catalyst in an amount ranging from 0.05 to 7 wt %, e.g., 0.1 to 7 wt %, or 0.5 to 7 wt %, or 1 to 7 wt %, or 2 to 7 wt %, based on the total weight of the catalyst. In some embodiments, platinum is present in the catalyst in an amount ranging from 0.05 to 5 wt %, e.g., 0.1 to 5 wt %, or 0.5 to 5 wt %, or 1 to 5 wt %, or 2 to 5 wt %, based on the total weight of the catalyst. For example, in some embodiments of the present disclosure described herein, platinum is present in the catalyst in an amount ranging from 0.05 to 2 wt %, e.g., 0.1 to 2 wt %, or 0.3 to 2 wt %, or 0.5 to 2 wt %, based on the total weight of the catalyst. In some embodiments, platinum is present in the catalyst in an amount ranging from 0.05 to 1.5 wt %, e.g., 0.1 to 1.5 wt %, or 0.3 to 1.5 wt %, or 0.5 to 1.5 wt %, based on the total weight of the catalyst. In some embodiments, platinum is present in an amount ranging from 0.05 to 1 wt %, e.g., 0.1 to 1 wt %, or 0.3 to 1 wt %, or 0.5 to 1 wt %, based on the total weight of the catalyst. In some embodiments, platinum is present in an amount ranging from 0.05 to 0.8 wt %, e.g., 0.1 to 0.8 wt %, or 0.3 to 0.8 wt %, or 0.5 to 0.8 wt %, based on the total weight of the catalyst.

[0027] In various embodiments described elsewhere herein, palladium is present in the catalyst. For purposes of this disclosure, the amount of palladium present is calculated as the weight percent of palladium atoms in the catalyst based on the total weight of the catalyst, regardless of the form in which the palladium may be present. Palladium may be present in various forms in the catalyst; most commonly, palladium is present primarily as the metal, a metal oxide, or a combination thereof. In some embodiments of the present disclosure described herein, palladium is present in the catalyst in an amount ranging from 0.05 to 10 wt %, e.g., from 0.1 to 10 wt %, or from 0.5 to 10 wt %, or from 1 to 10 wt %, or from 2 to 10 wt %, or from 5 to 10 wt %, based on the total weight of the catalyst. For example, in some embodiments, palladium is present in the catalyst in an amount ranging from 0.05 to 7 wt %, e.g., from 0.1 to 7 wt %, or from 0.5 to 7 wt %, or from 1 to 7 wt %, or from 2 to 7 wt %, based on the total weight of the catalyst. In some embodiments, palladium is present in the catalyst in an amount ranging from 0.05 to 5 wt %, e.g., from 0.1 to 5 wt %, or from 0.5 to 5 wt %, or from 1 to 5 wt %, or from 2 to 5 wt %, based on the total weight of the catalyst. For example, in some embodiments of the present disclosure described herein, palladium is present in the catalyst in an amount ranging from 0.05 to 2 wt %, e.g., from 0.1 to 2 wt %, or from 0.3 to 2 wt %, or from 0.5 to 2 wt %, based on the total weight of the catalyst. In some embodiments, palladium is present in the catalyst in an amount ranging from 0.05 to 1.5 wt %, e.g., from 0.1 to 1.5 wt %, or from 0.3 to 1.5 wt %, or from 0.5 to 1.5 wt %, based on the total weight of the catalyst. In some embodiments, palladium is present in an amount ranging from 0.05 to 1 wt %, e.g., from 0.1 to 1 wt %, or from 0.3 to 1 wt %, or from 0.5 to 1 wt %, based on the total weight of the catalyst. In some embodiments, palladium is present in the catalyst in an amount in the range of 0.05 to 0.8 wt %, e.g., 0.1 to 0.8 wt %, or 0.3 to 0.8 wt %, or 0.5 to 0.8 wt %, based on the total weight of the catalyst.

[0028] For example, in various embodiments described elsewhere herein, gold is present in the catalyst. For purposes of this disclosure, the amount of gold present is calculated as the weight percent of gold atoms in the catalyst based on the total weight of the catalyst, regardless of the form in which the gold may be present. Gold may be present in various forms in the catalyst; most commonly, gold is present primarily as the metal, metal oxide, or a combination thereof. In some embodiments of the present disclosure described herein, gold is present in the catalyst in an amount ranging from 0.05 to 10 wt %, e.g., 0.1 to 10 wt %, or 0.5 to 10 wt %, or 1 to 10 wt %, or 2 to 10 wt %, or 5 to 10 wt %, based on the total weight of the catalyst. For example, in some embodiments, gold is present in the catalyst in an amount ranging from 0.05 to 7 wt %, e.g., 0.1 to 7 wt %, or 0.5 to 7 wt %, or 1 to 7 wt %, or 2 to 7 wt %, based on the total weight of the catalyst. In some embodiments, gold is present in the catalyst in an amount ranging from 0.05 to 5 wt %, e.g., 0.1 to 5 wt %, or 0.5 to 5 wt %, or 1 to 5 wt %, or 2 to 5 wt %, based on the total weight of the catalyst. For example, in some embodiments of the present disclosure described herein, gold is present in the catalyst in an amount ranging from 0.05 to 2 wt %, e.g., 0.1 to 2 wt %, or 0.3 to 2 wt %, or 0.5 to 2 wt %, based on the total weight of the catalyst. In some embodiments, gold is present in the catalyst in an amount ranging from 0.05 to 1.5 wt %, e.g., 0.1 to 1.5 wt %, or 0.3 to 1.5 wt %, or 0.5 to 1.5 wt %, based on the total weight of the catalyst. In some embodiments, gold is present in an amount ranging from 0.05 to 1 wt %, e.g., 0.1 to 1 wt %, or 0.3 to 1 wt %, or 0.5 to 1 wt %, based on the total weight of the catalyst. In some embodiments, gold is present in the catalyst in an amount ranging from 0.05 to 0.8 wt %, e.g., from 0.1 to 0.8 wt %, or from 0.3 to 0.8 wt %, or from 0.5 to 0.8 wt %, based on the total weight of the catalyst.

[0029] As noted above, the supported reverse water gas shift catalyst of the present disclosure also contains manganese. The inventors have determined that including manganese in the catalyst can result in improved performance, as described in the Examples below. For purposes of this disclosure, the amount of manganese present is calculated as the weight percent of manganese atoms in the catalyst based on the total weight of the catalyst, regardless of the form in which the manganese may be present. Manganese may be present in the catalyst in various forms; most commonly, manganese is present primarily as a metal oxide, a metal, or a combination thereof. In various embodiments of the present disclosure described elsewhere herein, manganese is present in the catalyst in an amount ranging from 0.5 to 20 wt %, based on the total weight of the catalyst. For example, in various embodiments, manganese is present in the catalyst in an amount ranging from 0.5 to 15 wt %, or from 0.5 to 12 wt %, or from 0.5 to 10 wt %, based on the total weight of the catalyst. In various embodiments of the present disclosure described herein, manganese is present in the catalyst in an amount ranging from 1 to 20 wt%, e.g., from 1 to 15 wt%, or from 1 to 12 wt%, or from 1 to 10 wt%, based on the total weight of the catalyst. In various embodiments of the present disclosure described herein, manganese is present in an amount ranging from 2 to 20 wt%, e.g., from 2 to 15 wt%, or from 2 to 12 wt%, or from 2 to 10 wt%, based on the total weight of the catalyst. In various embodiments of the present disclosure described herein, manganese is present in an amount ranging from 4 to 20 wt%, e.g., from 4 to 15 wt%, or from 4 to 12 wt%, or from 4 to 10 wt%, based on the total weight of the catalyst.

[0030] The platinum, palladium, and / or gold and manganese may be provided in various weight ratios. For example, in some embodiments of the present disclosure described herein, the weight ratio of platinum, palladium, and / or gold to manganese present in the catalyst is at least 0.05:1. For example, in various embodiments, the weight ratio of platinum, palladium, and / or gold to manganese is at least 0.1:1. In various embodiments of the present disclosure described herein, the weight ratio of platinum, palladium, and / or gold to manganese present in the catalyst is at most 1:1. For example, the weight ratio of platinum, palladium, and / or gold to manganese is at most 0.5:1. For example, in various embodiments, the weight ratio of platinum, palladium, and / or gold to manganese present in the catalyst ranges from 0.05:1 to 1:1. For example, the weight ratio of platinum, palladium, and / or gold to manganese ranges from 0.05:1 to 0.5:1, or from 0.05:1 to 0.3:1, or from 0.07:1 to 1:1, or from 0.07:1 to 0.5:1, or from 0.07:1 to 0.3:1, or from 0.1:1 to 1:1, or from 0.1:1 to 0.5:1, or from 0.1:1 to 0.3:1.

[0031] The inventors have determined that a suitable reverse water gas shift catalyst can be formed from one or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide as a support and have platinum, palladium, and / or gold in combination with manganese contained in / on the catalyst. As will be understood by those skilled in the art, the amounts of cerium, titanium, aluminum, zirconium, platinum, palladium, gold, and manganese can be quantified on a metal basis, regardless of the form in which these metals may exist. For example, the amounts of these metals can be calculated as a weight percent based on the total weight of the metals in the catalyst (i.e., on a metal basis), without including oxygen or non-metallic counterions in the calculation. Thus, in various embodiments of the present disclosure described herein, the total amount of cerium, titanium, aluminum, zirconium, manganese, platinum, palladium, and gold in the catalyst is at least 90% by weight, e.g., at least 95% by weight, or at least 98% by weight, of the catalyst on a metal basis. For example, in some particular embodiments, the total amount of cerium, manganese, platinum, palladium, and gold in the catalyst is at least 90% by weight, e.g., at least 95% by weight, or at least 98% by weight, of the catalyst on a metals basis. In other embodiments, the total amount of titanium, manganese, platinum, palladium, and gold in the catalyst is at least 90% by weight, e.g., at least 95% by weight, or at least 98% by weight, of the catalyst on a metals basis. In other embodiments, the total amount of aluminum, manganese, platinum, palladium, and gold in the catalyst is at least 90% by weight, e.g., at least 95% by weight, or at least 98% by weight, of the catalyst on a metals basis. In other embodiments, the total amount of zirconium, manganese, platinum, palladium, and gold in the catalyst is at least 90% by weight, e.g., at least 95% by weight, or at least 98% by weight, of the catalyst on a metals basis.

[0032] As described above, the catalysts described herein are composed predominantly of cerium, titanium, aluminum, zirconium, manganese, platinum, palladium, and / or gold. In some embodiments described herein, the catalyst has an additional metal content of 10 wt. % or less, based on the total weight of the catalyst. The additional metal may be any metal other than platinum, palladium, gold, manganese, cerium, titanium, aluminum, or zirconium. For example, the additional metal may be selected from alkali metals, alkaline earth metals, rare earth metals, coinage metals, or other transition metals. For example, in various embodiments, the catalyst has an additional metal content of 5 wt. % or less, or 2 wt. % or less, or 1 wt. % or less, based on the total weight of the catalyst. In some embodiments described herein, the catalyst has a copper content of 10 wt. % or less, based on the total weight of the catalyst. For example, in various embodiments, the catalyst has a copper content of 5 wt. % or less, or 2 wt. % or less, or 1 wt. % or less, based on the total weight of the catalyst. In some embodiments described herein, the catalyst has an alkali metal content of 10 wt. % or less, based on the total weight of the catalyst. For example, in various embodiments, the catalyst has an alkali metal content of 5 wt.% or less, or 2 wt.% or less, or 1 wt.% or less, based on the total weight of the catalyst. In some embodiments described herein, the catalyst has an alkaline earth metal content of 10 wt.% or less, based on the total weight of the catalyst. For example, in various embodiments, the catalyst has an alkaline earth metal content of 5 wt.% or less, or 2 wt.% or less, or 1 wt.% or less, based on the total weight of (a) and (b).

[0033] As described above, the supported catalyst contains manganese and at least one of platinum, palladium, and gold. Depending on the synthesis process, these species are typically present primarily in metallic and / or oxide form and can be located in a variety of different locations on the support. For example, they can be found in the pores of the support and on the outer surface of the support. They can be found substantially throughout the support, for example, when a large amount of impregnation solution is used, or only in the surface layer of the support if the impregnation solution does not penetrate the entire support, for example, when using an incipient wetness technique.

[0034] While not intending to be bound by theory, it is believed that the active forms of platinum, palladium, and gold are typically substantially metallic forms. As described below, platinum, palladium, and gold may exist substantially in oxide form after catalyst preparation and during transportation and storage, and therefore it is typically desirable to activate the catalyst by contacting the catalyst with a reducing agent, such as hydrogen gas, to convert a substantial fraction of such oxides to the metallic form. However, those skilled in the art will understand that the present disclosure contemplates the usefulness of a wide variety of palladium, platinum, and gold forms in the catalyst, as these may be active or may be conveniently converted to the active form.

[0035] Manganese is typically provided in oxide form after catalyst preparation and during transportation and storage. Without being bound by theory, the inventors believe that manganese acts to improve the catalytic activity of supported platinum, palladium, and / or gold catalysts by reducing CO methanation, which can occur over a typical reverse water gas shift reaction temperature range, affecting CO selectivity. The inventors believe that the improved activity can be attributed to manganese interfacing with both the platinum, palladium, and / or gold and the support (e.g., cerium oxide, titanium oxide, aluminum oxide, zirconium oxide, or mixed oxide). The inventors believe that some manganese oxide may be converted to a metallic form during activation of the platinum, palladium, and / or gold species. However, those skilled in the art will understand that the present disclosure contemplates the usefulness of a wide variety of manganese forms in the catalyst, as they may provide a promoting effect or may be conveniently converted to a form that provides a promoting effect.

[0036] Those skilled in the art will understand that the catalysts of the present disclosure can be provided in many forms, for example, in a fixed bed or as a fluidized bed, depending particularly on the particular configuration of the reactor system in which they are used. The support itself can be provided as a separate body of material, for example, as porous particles, pellets, or shaped extrudates, onto which platinum, palladium, and / or gold and manganese are provided to provide the catalyst. However, in other embodiments, the catalysts of the present disclosure can themselves be formed as a layer on an 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 understand, for example, that a layer of support can be provided on a substrate using coating or other forming techniques, and then platinum, palladium, and / or gold and manganese can be added.

[0037] Another aspect of the present disclosure provides a method for making the catalyst described herein. As described above, the method includes providing a support that is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support containing a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; contacting the support with one or more liquids each containing one or more platinum-, palladium-, or gold-containing compounds and / or one or more manganese-containing compounds dispersed in a solvent; evaporating the solvent to provide a catalyst precursor; and calcining the catalyst precursor. Those skilled in the art will understand, of course, that other methods can be used to make the catalyst described herein.

[0038] In some embodiments of the present disclosure described herein, contacting the support with a liquid comprises adding the liquid in an amount approximately equal to (i.e., within 25%, or within 10%) the pore volume of the support. In other embodiments, contacting the support with a liquid comprises adding the liquid in an amount greater than the pore volume of the support. For example, in some embodiments, the ratio of the amount of liquid to the amount of support, by weight, is in the range of 0.75:1 to 5:1, e.g., 0.9:1 to 3:1. In some embodiments, contacting the support with a liquid results in a slurry.

[0039] In various embodiments of the present disclosure described herein, evaporating the solvent is carried out at ambient temperature. In various embodiments, evaporating the solvent is carried out at an elevated temperature for a drying period. Those skilled in the art can select an appropriate device or equipment for evaporating the solvent, and such device or equipment is not particularly limited. Furthermore, those skilled in the art will understand that the elevated temperature for evaporating the solvent depends on the boiling point of the solvent. Therefore, those skilled in the art will be able to select an appropriate elevated temperature. For example, in some embodiments, the elevated temperature is in the range of 50 to 150°C, e.g., 50 to 120°C, or 50 to 100°C, or 100 to 150°C, or 100 to 120°C. In some embodiments, the drying time is in the range of 1 to 48 hours, e.g., 10 to 36 hours, or 12 to 24 hours. For example, in certain embodiments, the drying time is about 24 hours. In some embodiments, evaporating the solvent is carried out under vacuum and at an elevated temperature for a drying period, as described herein. In some embodiments, evaporating the solvent is carried out in a stirred drying bath at an elevated temperature, e.g., 30 to 100°C.

[0040] In some embodiments of the present disclosure described herein, calcining the catalyst precursor is performed in a furnace for a calcination time and a calcination temperature. For example, in some embodiments, the calcination time ranges from 0.5 to 24 hours, or from 0.5 to 15 hours, or from 0.5 to 10 hours, or from 0.5 to 5 hours. In some embodiments, the calcination temperature ranges from 100 to 600°C, e.g., from 120 to 500°C.

[0041] As described above, the method for making the catalyst described herein includes contacting a support with one or more liquids each containing one or more platinum-, palladium-, or gold-containing compounds and / or one or more manganese-containing compounds dispersed in a solvent. The platinum-, palladium-, gold-, and manganese-containing compounds are not particularly limited, and one skilled in the art can select appropriate compounds that are soluble in the solvent. For example, in some embodiments of the present disclosure described herein, the platinum-, palladium-, gold-, and manganese-containing compounds can be selected from metal salts (e.g., nitrates and acetates). The solvent is also not particularly limited, and one skilled in the art can select an appropriate solvent that can be absorbed by the support. For example, in some embodiments of the present disclosure described herein, the solvent is water. As one skilled in the art will understand, these metal species are conveniently provided in the same liquid, so that only one step of contacting the support with the liquid is required. However, other schemes are possible.

[0042] In another aspect, the present disclosure provides a catalyst described herein made by a method described herein.

[0043] Reverse Water Gas Shift Reaction Another aspect of the present disclosure provides a method for performing a reverse water gas shift reaction. As described above, the method includes contacting a catalyst described herein with a feed stream containing CO and H at a temperature ranging from 200 to 900°C to provide a product stream containing CO and H, the product stream having a lower CO concentration and a higher CO concentration than the feed stream. An example of such a method is shown schematically in FIG. 1. In FIG. 1, the method 100 includes conducting a reverse water gas shift reaction by supplying a feed stream 111, here consisting of H and CO, to a reaction zone, e.g., reactor 110. A reverse water gas shift catalyst 113 described herein contacts the feed stream 111 at a temperature ranging from 200 to 900°C to provide a product stream 112 containing CO and H. The product stream has a lower concentration of CO and a higher concentration of CO than the feed stream.

[0044] As used herein, "feed stream" is used to mean all materials input to a process step, whether provided in a single physical stream or multiple physical streams, and whether through a single inlet or multiple inlets. For example, the H and CO feed streams may 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 H, or one inlet for fresh CO and H and another inlet for recycled CO and / or H). Similarly, "product stream" is used to mean all materials output from a process step, whether provided in a single physical stream or multiple physical streams, and whether through a single outlet or multiple outlets.

[0045] In various embodiments of the present disclosure described herein, 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 feed (here, CO) that is converted to the product ("CO selectivity", relative to CO). The inventors have determined that the present catalyst can provide excellent selectivity for CO, even when operated at lower temperatures than many conventional reverse water gas shift catalysts, despite possible competition from the Sabatier reaction and CO methanation. For example, in some embodiments described elsewhere herein, the reverse water gas shift reaction has a CO selectivity of at least 98%, e.g., or at least 99%.

[0046] In particular, even at relatively low temperatures in the range of 200-900°C, the 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 elsewhere 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.

[0047] The inventors have determined that the catalysts described herein can provide desirably high CO selectivity and desirably low methane selectivity at commercially relevant conversions. As used herein, "conversion" refers to the mole fraction of the feedstock that is reacted (to desired products or undesired species). In various embodiments of the present disclosure described herein, the reverse water gas shift reaction has a CO conversion of at least 5%, e.g., at least 10%, or 20%. For example, in some embodiments, the reverse water gas shift reaction has a CO conversion of at least 30%, e.g., at least 40%, or 50%, or 60%. In various embodiments of the present disclosure described herein, the reverse water gas shift reaction has a CO conversion of 90% or less, e.g., 80% or less, or 70% or less. For example, in some embodiments, the reverse water gas shift reaction has a CO conversion of 65% or less, e.g., 60% or less. For example, in various embodiments described elsewhere herein, CO conversions range from 10 to 90%, e.g., 10 to 80%, or 10 to 70%, or 10 to 60%, or 10 to 65%, or 20 to 90%, or 20 to 80%, or 20 to 70%, or 20 to 60%, or 20 to 65%, or 30 to 90%, or 30 to 80%, or 30 to 70%, or 30 to 60%, or 30 to 65%, or 40 to 90%, or 40 to 80%, or 40 to 70%, or 40 to 60%, or 40 to 65%. One skilled in the art, based on the disclosure herein, will operate at a conversion that provides the desired product. Of course, in other embodiments, CO conversions can be even higher than those described herein, for example, when in stacked bed or mixed bed systems.

[0048] Advantageously, the processes described herein can be carried out at temperatures lower than those used in many conventional reverse water gas shift processes. As noted above, various processes of the present disclosure can be carried out at temperatures ranging from 200 to 900°C. For example, in some embodiments, the method for carrying out the reverse water gas shift reaction is carried out at a temperature ranging from 200 to 850°C, e.g., from 200 to 800°C, or from 200 to 750°C, or from 200 to 700°C, or from 200 to 650°C, or from 200 to 600°C. In some embodiments, the method for carrying out the reverse water gas shift reaction is carried out at a temperature ranging from 250 to 900°C, e.g., from 250 to 850°C, or from 250 to 800°C, or from 250 to 700°C, or from 250 to 650°C, or from 250 to 600°C. In some embodiments of the disclosure described herein, the method for conducting the reverse water gas shift reaction is carried out at a temperature in the range of 300 to 900° C., e.g., 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 disclosure described herein, the method for conducting the reverse water gas shift reaction is carried out at a temperature in the range of 350 to 900° C., e.g., 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 conducting the reverse water gas shift reaction is carried out at a temperature in the range of 400-900° C., e.g., 400-850° C., or 400-800° C., or 400-750° C., or 400-700° C., or 400-650° C., or 400-600° C. In some embodiments, the method for conducting the reverse water gas shift reaction is carried out at a temperature in the range of 450-900° C., e.g., 450-850° C., or 450-800° C., or 450-750° C., or 450-700° C., or 450-650° C., or 450-600° C.In some embodiments, the method for conducting the reverse water gas shift reaction is carried out at a temperature in the range of 500-900° C., e.g., 500-850° C., or 500-800° C., or 500-750° C., or 500-700° C., or 500-650° C., or 500-600° C. In some embodiments, the method for conducting the reverse water gas shift reaction is carried out at a temperature in the range of 550-900° C., e.g., 550-850° C., or 550-800° C., or 550-750° C., or 550-700° C., or 550-650° C., or 550-600° C.

[0049] In some embodiments, the reverse water gas shift reaction is carried out at a temperature in the range of 200-500° C., e.g., 200-450° C., or 200-400° C., or 200-350° C., or 250-500° C., or 250-450° C., or 250-400° C., or 250-350° C. The inventors have noted that operation at these temperatures can provide lower energy demands.

[0050] As described above, the feed stream includes CO and H. Advantageously, the inventors recognize that both of these can come from renewable or other environmentally responsible sources. For example, at least a portion of the H can be so-called "green" hydrogen, produced from, for example, water electrolysis operated using renewable electricity (such as wind, solar, or hydroelectric power). In other embodiments, at least a portion of the H may be from so-called "blue" sources, such as natural gas reforming processes with carbon capture. Of course, other hydrogen sources can be used, partially or completely. For example, in some embodiments, at least a portion of the H in the feed stream is gray hydrogen, black hydrogen, brown hydrogen, pink hydrogen, turquoise hydrogen, yellow hydrogen, and / or white hydrogen. CO can generally be captured from the environment or from processes that more directly form CO (especially in sectors where it is difficult to remove), creating products that are subsequently made from at least carbon-neutral CO. For example, in some embodiments, at least a portion of the CO is from direct air capture or from a manufacturing plant such as a bioethanol plant (e.g., CO-generating fermentation), a steel mill, or a cement factory. Thus, the rWGS reaction is not only carbon neutral, but can in some cases be a net consumer of carbon dioxide. These advantages make the rWGS reaction very attractive for decarbonizing transportation fuels for both the automotive and aviation sectors, especially since the carbon monoxide produced in the reaction can be readily utilized by well-established technologies for synthesizing liquid hydrocarbon fuels.

[0051] The feed stream contains both H and CO (e.g., provided to the reaction zone in a single physical stream or multiple physical streams). As used herein, a feed stream includes all feeds to a process, whether provided as a mixture of gases or as gases provided individually to the reaction zone. In various embodiments described elsewhere herein, the molar ratio of H to CO in the feed stream is at least 0.1:1, e.g., at least 0.5:1. In some embodiments, the molar ratio of H to CO in the feed stream is at least 0.9:1, e.g., 1:1 or at least 1.5:1. In some embodiments, the molar ratio of H to CO in the feed stream is at least 2:1, e.g., at least 2.5:1. In some embodiments, the molar ratio of H to CO in the 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 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 feed stream ranges from 0.5:1 to 10:1. One skilled in the art, based on the disclosure herein, will provide a desired ratio of H2:CO2 in the feed stream that provides a desired conversion and selectivity, and, if consistent with the desired conversion and selectivity, can provide excess H2 to flow through the system to provide a product stream having a desired ratio of H2 to CO2 for downstream processing.

[0052] Other gases may also be included in the feed stream. For example, in some embodiments, the feed stream further comprises CO. In some embodiments of the present disclosure described elsewhere herein, the feed stream further comprises one or more inert gases. For example, in some embodiments, the feed stream further comprises nitrogen and / or methane.

[0053] The processes described herein can be carried out at a variety of pressures, as will be appreciated by those skilled in the art. In various embodiments of the present disclosure, the method for carrying out the reverse water gas shift reaction is carried out at a pressure ranging from 1 to 100 barg. For example, the method is carried out at a pressure ranging from 1 to 70 barg, or from 1 to 50 barg, or from 1 to 40 barg, or from 1 to 35 barg, or from 5 to 70 barg, or from 5 to 50 barg, or from 5 to 40 barg, or from 5 to 35 barg, or from 10 to 70 barg, or from 10 to 50 barg, or from 10 to 40 barg, or from 10 to 35 barg, or from 20 to 70 barg, or from 20 to 50 barg, or from 20 to 40 barg, or from 20 to 35 barg, or from 25 to 70 barg, or from 25 to 50 barg, or from 25 to 40 barg, or from 25 to 35 barg.

[0054] The process described herein can be carried out at various GHSV (gas hourly space velocity), as will be understood by those skilled in the art. 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 of performing the reverse water gas shift reaction is performed at a GHSV ranging from 1,000 to 1,200,000 h, or from 1,000 to 500,000 h, or from 1,000 to 100,000 h, or from 5,000 to 1,200,000 h, or from 5,000 to 500,000 h, or from 5,000 to 100,000 h, or from 10,000 to 1,200,000 h, or from 10,000 to 500,000 h, or from 10,000 to 100,000 h. In various embodiments of the present disclosure, the process of conducting the reverse water gas shift reaction is carried out at a GHSV ranging from 1,000 to 50,000 h, or from 2,000 to 50,000 h, or from 5,000 to 50,000 h, or from 10,000 to 50,000, or from 1,000 to 40,000 h, or from 2,000 to 40,000 h, or from 5,000 to 40,000 h, or from 10,000 to 40,000 h, or from 1,000 to 30,000 h, or from 2,000 to 30,000 h, or from 5,000 to 30,000 h, or from 10,000 to 30,000 h.

[0055] The rWGS catalysts described herein are based in part on platinum, palladium, and / or gold. It is typically desirable to activate the rWGS catalyst, e.g., before contacting it with a feed stream. Accordingly, in some embodiments of the present disclosure described herein, the method includes activating the rWGS catalyst before contacting it with a feed stream. For example, in some embodiments, activating the catalyst includes contacting the catalyst with a reducing stream containing a reducing gas, e.g., hydrogen. In various embodiments of the present disclosure, the reducing stream contains hydrogen in an amount of at least 25 mol%, e.g., at least 50 mol%, or 75 mol%, or 90 mol%. Those skilled in the art will determine suitable conditions for activating the rWGS catalyst. Accordingly, those skilled in the art will be able to select appropriate temperatures, pressures, and times for activating the rWGS catalyst. For example, in various embodiments, the catalyst activation is performed at a temperature ranging from 200°C to 800°C. In some embodiments, activating the catalyst is carried out at a temperature ranging from 250° C. to 800° C., or from 300° C. to 800° C., or from 200° C. to 700° C., or from 250° C. to 800° C., or from 300° C. to 700° C. In some embodiments of the disclosure described herein, activating the catalyst provides a catalyst that is at least 10% reduced (e.g., at least 25%, or at least 50% reduced).

[0056] The inventors have found that contacting a feed stream with an rWGS catalyst as described herein can advantageously provide a product stream having high CO selectivity and low methane selectivity. The amount of CO in the product stream can be further controlled by the rWGS reaction conditions, as described above. However, in general, methods for conducting an rWGS reaction as described herein provide a product stream comprised of H and CO, with the product stream having a lower concentration of CO and a higher concentration of CO than the feed stream, consistent with the degrees of conversion described herein. For example, in various embodiments, the product stream contains 95 mol% or less CO, or 90 mol% or less CO. In some embodiments, the product stream contains 85 mol% or less CO, or 80 mol% or less CO. In other examples, the product stream contains 75 mol% or less CO, or 70 mol% or less CO. However, as described above, the inventors have determined that it may be desirable to run the process at intermediate degrees of conversion to provide a desirably high CO selectivity and a desirably low methane selectivity. Thus, in various embodiments as described elsewhere herein, the product stream includes CO along with an amount of CO.

[0057] Other gases may also be included in the product stream. In some embodiments of the present disclosure described elsewhere herein, the product stream further comprises one or more inert gases. These inert gases may be included in the feed stream or may be provided from a source other than the feed stream. For example, in some embodiments, the product stream further comprises nitrogen and / or methane.

[0058] Depending on, among other things, the degree of conversion, CO selectivity, the relative amounts of H and CO in the feed stream, and the reaction conditions, the product stream can contain H in combination with CO in various ratios. For example, in some embodiments, the ratio of H:CO in the product stream ranges from 0.1:1 to 100:1 (e.g., from 0.1:1 to 50:1, or from 0.1:1 to 25:1, or from 0.1:1 to 10:1, or from 0.1:1 to 5:1, or from 1:1 to 100:1, or from 1:1 to 50:1, or from 1:1 to 25:1, or from 1:1 to 10:1, or from 1:1 to 5:1).

[0059] Those skilled in the art will understand that, based on the methods described herein, the product stream may contain varying amounts of H, CO, and CO, as well as other components. The components of the product stream may be separated and used for various purposes in the rWGS process.

[0060] For example, in various embodiments of the disclosure described herein, the method further comprises separating the 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 product stream to the feed stream. For example, if the product stream comprises CO, the method can comprise 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 CO of the product stream to the feed stream. The product stream may also comprise H, and in some embodiments, the method further comprises 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 H of the product stream to the feed stream.

[0061] Such recycling is illustrated in process 100 of Figure 1 (and Figure 2), where process 100 includes separating at least a portion of the CO (Stream 114) from product stream 112 for recycling to feed stream 111. Similarly, process 100 includes separating at least a portion of the H (Stream 115) from product stream 112 for recycling to product stream 111. Although stream 115 is shown as entering reactor 110 through a different inlet than the rest of feed stream 111, it is considered part of the feed stream because it is part of the material input to the process step.

[0062] As mentioned above, one competing reaction in the reverse water gas shift reaction is the Sabatier reaction, which produces methane. In various embodiments, the reverse water gas shift processes described herein can be performed without forming significant amounts of methane, although in some embodiments, some methane may be formed. Thus, in various embodiments of the methods described herein, the product stream includes one or more light hydrocarbons. For example, in some embodiments, the product stream may include one or more of methane, ethane, propane, or a combination thereof. As will 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 product feed. For example, such light hydrocarbons may be inert in further processing of the product stream and therefore may be tolerated in higher amounts. One skilled in the art will be able to select appropriate reaction conditions (e.g., temperature, pressure, feed stream composition) to provide a product stream containing methane in a desired amount. For example, in various embodiments described elsewhere herein, the product stream includes 20 mol% or less methane or 15 mol% or less methane. As discussed above, when a lower amount of methane in the product stream is desired, the catalysts of the present disclosure can provide very low methane selectivity. Accordingly, in various embodiments described elsewhere herein, the product stream contains 10 mol% or less of methane. For example, in various embodiments, the product stream contains 5 mol% or less, or 1 mol% or less, or 0.5 mol% or less, or 0.1 mol% or less of methane. Generally, light hydrocarbons (e.g., C1-C5 hydrocarbons) may be present in the product stream. For example, in various embodiments described elsewhere herein, the product stream contains 20 mol% or less of 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 of light hydrocarbons).

[0063] These light hydrocarbons (e.g., C1-C5 hydrocarbons) of the product stream can be separated and used for other purposes. For example, in various embodiments, the method further includes separating at least a portion of the one or more light hydrocarbons from the product stream to provide a light hydrocarbon stream. For example, in method 100 of FIG. 1, at least a portion of the one or more light hydrocarbons is separated from product stream 112 to provide light hydrocarbon stream 116. The light hydrocarbon stream can be used to provide other products, for example, 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 the rWGS process or other processes.

[0064] Of course, as will be appreciated by those skilled in the art, the light hydrocarbon stream can be used in other processes as well. For example, as will be appreciated by those skilled in the art, some rWGS catalysts can have reforming capabilities. Without wishing to be 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 H. Accordingly, in some embodiments described herein, the light hydrocarbons of the process stream are recycled to the feed stream for the rWGS reaction. These light 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 the first product stream to provide a light hydrocarbon stream. For example, in process 100 of FIG. 2, at least a portion of one or more light hydrocarbons is separated from first product stream 112 to provide light hydrocarbon stream 118. The light hydrocarbon stream may, for example, be used to provide other products, may be partially oxidized to form CO, may be steam reformed to provide hydrogen, and / or may be combusted to provide heat or other energy (e.g., electricity for electrolysis) for use in an integrated process or otherwise. Of course, as will be appreciated by those skilled in the art, the light hydrocarbon stream may be used in other processes as well.

[0065] Integrated Fischer-Tropsch Process In some embodiments described herein, the supported reverse water gas shift can be used in an rWGS process integrated with a FT process. Embodiments related to the reverse water gas shift portion of the integrated FT process are described above in the previous section. For example, the feed stream of the rWGS process corresponds to the first feed stream in the integrated FT process, and the product stream of the rWGS process corresponds to the first product stream in the integrated FT process.

[0066] Another aspect of the present disclosure provides a process for conducting an integrated Fischer-Tropsch process (i.e., integrated with an rWGS process). The method includes providing a first feed stream containing H and CO; and contacting a reverse water gas shift catalyst described herein with the first feed stream at a first temperature in the range of 200-900°C and a first pressure to conduct a reverse water gas shift reaction and provide a first product stream containing CO and H, where the first product stream has a lower CO concentration and a higher CO concentration than the first feed stream. An example of such a process is shown schematically in FIG. 2. In FIG. 2, process 100 includes conducting a reverse water gas shift reaction by supplying a first feed stream 111 consisting of H and CO to a first reaction zone, here reactor 110. A reverse water gas shift catalyst 113 described herein contacts feed stream 111 at a first temperature in the range of 200-900°C and a first pressure to provide a first product stream 112 containing CO and H. 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 disclosure also includes 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. In the method 100 of Figure 2, at least a portion of the CO of the first product stream 112 is included in a second feed stream 121, which is now contacted with a Fischer-Tropsch catalyst 123 in a second reaction zone (e.g., reactor 120). This provides a second product stream 122 comprising C5+ hydrocarbons.

[0067] The inventors have discovered that contacting a first feed stream with an rWGS catalyst as described herein can provide a first product stream having advantageously high CO selectivity and low methane selectivity. The amount of CO in the first product stream can be further controlled by the rWGS reaction conditions, as described above.

[0068] However, as noted above, the inventors have determined that it may be desirable to operate the process at intermediate degrees of conversion to provide desirably high CO selectivity and desirably low methane selectivity. Furthermore, the inventors have noted that it may be advantageous to operate the downstream Fischer-Tropsch process with relatively high levels of inerts, and therefore believe that it may be beneficial to pass a significant amount of CO through the Fischer-Tropsch process step. Thus, in various embodiments described elsewhere herein, the first product stream includes CO along with an amount of CO. In various embodiments, the first product stream comprises 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 20 to 80 mol%, or 20 to 75 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.

[0069] Furthermore, as described below, Fischer-Tropsch catalysts typically require activation with a reducing gas. As will be appreciated 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 with both H and CO, while cobalt-based Fischer-Tropsch catalysts require activation with H alone. Thus, this activation can be performed using H and CO from the first product stream, or H alone. Accordingly, in various embodiments described elsewhere herein, the method includes separating at least a portion of the H and CO from the first product stream (desirably in a ratio of at least 1:1 or at least 3:1) and contacting it with a Fischer-Tropsch catalyst to activate the Fischer-Tropsch catalyst. In various other embodiments described elsewhere herein, the method includes separating at least a portion of the H from the first product stream and contacting it with a Fischer-Tropsch catalyst to activate the Fischer-Tropsch catalyst. For example, in the process of Figure 2, stream 125 separates H or H and CO and directs it to reactor 120. This separation need not be continuous, but rather only occurs for as long as desired to provide reducing gas to the Fischer-Tropsch catalyst for activation. Of course, as will be appreciated by those skilled in the art, other sources of H or CO may be used to provide reducing gas to the Fischer-Tropsch catalyst for activation.

[0070] As noted above, water is a product of the reverse water-gas shift reaction. Therefore, the first product stream generally contains water. It is often desirable to reduce the amount of water fed to a Fischer-Tropsch process step. Accordingly, in various embodiments described elsewhere herein, the process further includes removing at least a portion of the water from the first product stream (e.g., at least 25%, at least 50%, or at least 75%). In the embodiment of FIG. 2 , a water removal zone 116 is used to remove water and provide a water-containing stream 117. Those skilled in the art will appreciate that various processes 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 sieves in the guard bed by, for example, heating and vacuum. In other embodiments, a knock-out vessel can be used. However, the use of a knock-out vessel can, in some cases, sufficiently cool the first product stream so that it can be desirably reheated for introduction into a Fischer-Tropsch process step. The water removed from the first product stream can be used, for example, as feedwater for the electrolysis processes described herein.

[0071] As noted above, the reverse water gas shift process can be performed at a wide variety of temperatures. In some cases, these temperatures may be relatively close to the temperatures of the subsequent Fischer-Tropsch process steps (often 150-400°C, e.g., 200-350°C, or other temperatures described below). In other cases, the reverse water gas shift process can be performed at temperatures significantly higher than the temperatures of the Fischer-Tropsch process steps. 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 a temperature more suitable for the Fischer-Tropsch process and to provide heat elsewhere in the integrated process. For example, in various embodiments of the processes described elsewhere herein, the process 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 process is shown schematically in FIG. 3. 3, process 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, process 200 includes exchanging heat between at least a portion of first product stream 212 and at least a portion of first feed stream 211 in a first heat exchange zone 230, thereby cooling at least a portion of first product stream 212 and heating at least a portion of first feed stream 211. Those skilled in the art will appreciate that a wide variety of heat exchangers can be used for this purpose.

[0072] 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 process 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. 3 , where, after heat exchange with first feed stream 211, first product stream 212 is directed to steam generation zone 232, cooling first product stream 212 and providing heat to 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. 3 , electricity stream 264 is provided by generating electricity using steam generated in steam generation zone 232. Of course, as will be understood by those skilled in the art, steam generated in the steam generation zone can be used in other processes. In various embodiments, the steam can be used to heat the first feed stream. For example, in the embodiment of FIG. 3, vapor stream 266 generated in vapor generation zone 232 is directed to heat exchange zone 290 to heat first feed stream 211 .

[0073] As discussed above, at least a portion of the CO of the first product stream is included in the second feed stream for reaction in the Fischer-Tropsch process. For example, in various embodiments described elsewhere herein, at least 25% of the CO of the first product stream is included in the second feed stream, e.g., at least 50%, at least 75%, or at least 90% of the CO of the first product stream. Of course, as discussed above, a portion of the CO of the first product stream can be used for other purposes, such as catalyst activation as described herein.

[0074] In some embodiments, substantially all of the CO of the second feed stream comes from the first product stream. However, in other embodiments, CO may be provided to the second feed stream from other sources, fossil or otherwise. For example, in various embodiments, CO is provided to the second feed stream from a CO source other than the first product stream. In FIG. 3 , a stream of CO from other sources 226a is included in second feed stream 221. Those skilled in the art will appreciate that CO may be provided from a variety of sources, for example, gasification, reforming, or electrochemical CO reduction. Additionally, as described in more detail below, CO may be recycled from the second product stream to the second feed stream; and / or may be provided by reaction of a light hydrocarbon stream, for example, by partial oxidation or reforming (e.g., steam reforming and / or autothermal reforming).

[0075] As discussed above, the second feed stream includes H. In particular, the first product stream often includes unreacted H, for example, from the first feed stream. In various embodiments, the first product stream includes H, and the second feed stream includes at least a portion of the H from the first product stream. For example, in various embodiments as described elsewhere herein, at least 25% of the H from the first product stream, e.g., at least 50%, at least 75%, or at least 90% of the H from the first product stream, is included in the second feed stream. Of course, as discussed above, a portion of the H from the first product stream can be used for other purposes, such as catalyst activation as described herein.

[0076] In some embodiments, substantially all of the H2 in the second feed stream originates from the first product stream. Indeed, one skilled in the art can provide more H2 in the first feed stream than is required for the reverse water gas shift reaction to provide excess H2 in the first product stream and then provide the desired amount of H2 in the second feed stream for the Fischer-Tropsch process step. 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 a source other than the first product stream. In Figure 3, H2 from other source stream 226b is included in second feed stream 221. One skilled in the art will appreciate that H2 can be provided from a variety of sources, such as gasification, reforming, and H2O electrolysis (including electrolysis as described herein). Additionally, as described in more detail below, H2 can be recycled from the second product stream to the second feed stream.

[0077] Those skilled in the art will be able, based on the disclosure herein, to adjust the relative amounts of H and CO in the second feed stream to provide the desired ratio. For example, more or less H from the first feed stream and / or more or less H 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 (e.g., partial oxidation and reforming as described below) can be included in the second feed stream.

[0078] As mentioned above, it may be desirable to operate a Fischer-Tropsch process step in the presence of significant levels of inerts. One such inert, CO, may come from the reverse water gas shift, for example, via the first product stream. Accordingly, in various embodiments described elsewhere herein, the second feed stream comprises at least a portion of the CO of the first product stream. For example, in various embodiments, at least 10% of the CO of the first product stream, e.g., at least 25%, at least 50%, at least 75%, or at least 90% of the CO of the first product stream, is included in the second feed stream. Of course, in other embodiments, the second feed stream may not comprise any substantial amount of CO from the first product stream. Accordingly, in various embodiments, the second feed stream does not comprise a substantial amount of CO from the first product stream. Generally, it may be desirable to recycle the CO to the first feed stream for use in the reverse water gas shift reaction, although, as explained in more detail below, unreacted CO can be recycled from the second product stream to the first feed stream.

[0079] Additionally or alternatively, however, it may be desirable to include additional inert components in the second feed stream, be it CO or other inerts such as nitrogen and methane. For example, in various embodiments, one or more inerts (e.g., CO, nitrogen, and / or methane) are provided to the second feed stream from a source other than the first product stream. In FIG. 3, a stream of inerts from other sources 226c is included in the second feed stream 221. Those skilled in the art will appreciate that inerts can be provided from a variety of sources. Furthermore, as described in more detail below, inerts can be recycled from the second product stream to the second feed stream.

[0080] As noted above, it may be desirable to conduct a Fischer-Tropsch process step in the presence of an inert material. Thus, in various embodiments described elsewhere herein, the portion of the first product stream included in the second feed stream has a CO content in the range of 10-95 mol% CO, e.g., 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 20-70 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% CO.

[0081] Other gases may also be included in the second feed stream, as described above. For example, as described above, it may be desirable to perform a Fischer-Tropsch process step in the presence of a significant amount of inerts (i.e., components that are not H or CO). For example, in various embodiments, the second feed stream includes up to 80 mol% of one or more inerts, such as 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 comprises 70 mol% or less inerts, 60 mol% or less inerts, or 50 mol% or less inerts, for example, 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% inerts. In various embodiments, the second feed stream comprises up to 80% CO, e.g., 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% of one or more inerts selected from CO, methane, and nitrogen. In various embodiments, the second feed stream comprises up to 80 mol%, e.g., 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% CO. 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, the 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, e.g., 1:1 to 2.5:1. Of course, whatever the H2:CO ratio of the portion of the first product stream included in the second feed stream, one skilled in the art can add H2 or CO as needed, as described above, to provide the desired ratio in the entire second feed stream.

[0082] As described above, the second feed stream contains both H2 and CO, and whether the second feed stream is provided as a mixture of feeds or as separate feeds to the reaction zone, the second feed stream comprises all of the feed to the Fischer-Tropsch reactor. In various embodiments of the present disclosure described herein, the second feed stream has an H2:CO ratio ranging from 0.5:1 to 6:1. In some embodiments, the second feed stream has an H2:CO ratio ranging from 1:1 to 3:1, or from 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 ranging from 1.4:1 to 3:1, or from 1.4:1 to 2:1. One skilled in the art will be able to provide a desired ratio of H2:CO in the second feed stream based on the disclosure herein to provide the desired conversion and selectivity in a Fischer-Tropsch process.

[0083] As noted above, it may be desirable to reduce the amount of water sent to a Fischer-Tropsch process step. Thus, in various embodiments described elsewhere herein, the portion of the first product stream included in the second feed stream has a water content of 10 mol% or less, e.g., 2 mol% or less, or 0.5 mol% or less. Also, as noted above, it may be desirable to operate the Fischer-Tropsch process in the presence of relatively low amounts of water. Thus, in various embodiments, the second feed stream has a water content of 10 mol% or less, e.g., 2 mol% or less, or 0.5 mol% or less.

[0084] The methods described herein include contacting a Fischer-Tropsch catalyst with a 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 would be able to select an appropriate catalyst for the desired Fischer-Tropsch product. In some embodiments, the Fischer-Tropsch catalyst comprises cobalt, iron, rhodium, ruthenium, or a combination thereof.

[0085] For example, in some embodiments of the present disclosure described herein, the Fischer-Tropsch catalyst contains cobalt in an amount ranging from 5 to 25 wt. %, calculated as Co(0). "Calculated as Co(0)" and similar terms mean that the weight of the cobalt atoms / ions themselves is used in the calculation, not the total amount of any compounds or polynuclear ions to which those cobalt atoms / ions may be associated. For example, in various embodiments, the Fischer-Tropsch catalyst contains cobalt in an amount ranging from 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 one skilled in the art will appreciate, 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 H) to provide active catalytic species with significant concentrations of Co(0).

[0086] In some embodiments, the Fischer-Tropsch catalyst comprises iron in an amount ranging from 5 to 95 wt%, for example, 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 appreciated by those skilled in the art, iron-based catalysts are often provided 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 H and CO) to provide active catalytic species, including significant concentrations of iron carbide.

[0087] In various embodiments of the present disclosure 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 of 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 catalytic material comprises manganese in an amount ranging from 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).

[0088] The Fischer-Tropsch catalyst suitable for use in the methods described herein can be in a variety of forms, including but not limited to, for example, a supported or unsupported Fischer-Tropsch catalyst. While the form of the catalyst is not particularly limited, in various desirable embodiments, the Fischer-Tropsch catalyst is a supported catalyst, and the support comprises at least one of titanium oxide, zirconium oxide, cerium oxide, aluminum oxide, silicon oxide, and zinc oxide. For example, in various embodiments, the support comprises 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.

[0089] 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 particularly on the particular configuration of the reactor system in which they are used. The support for the Fischer-Tropsch catalyst itself can be provided as a discrete body of material, for example, porous particles, pellets, or shaped extrudates, onto which the metal is provided to provide the Fischer-Tropsch catalyst. However, in other embodiments, the Fischer-Tropsch catalyst of the present disclosure can itself be formed as a layer on an 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 be able to select a Fischer-Tropsch catalyst appropriate for a particular reactor system.

[0090] Similar to rWGS catalysts, Fischer-Tropsch catalysts are typically activated prior to use, for example, to provide cobalt(0) species on cobalt-based catalysts or iron carbide species on iron-based catalysts. Such activation can occur before contacting the Fischer-Tropsch catalyst with the second feed stream.

[0091] For example, in some embodiments, the Fischer-Tropsch catalyst is activated by contact with a reducing gas. For example, hydrogen may be a particularly suitable gas for activating a Fischer-Tropsch catalyst, for example, when the activation is by reduction to a metal(0) species, as is the case with many cobalt-based catalysts. In various embodiments of the present disclosure described elsewhere herein, the reducing gas comprises at least a portion of the H from the first product stream. For example, in some embodiments, the process further comprises separating at least a portion of the H from the first product stream and contacting it with a Fischer-Tropsch catalyst to activate the Fischer-Tropsch catalyst. In the process 100 shown generally in FIG. 2, at least a portion of the hydrogen stream 125 is separated from the first product stream 112 and contacts the Fischer-Tropsch catalyst 123 to activate it. In other embodiments, H 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 may vary depending on the Fischer-Tropsch catalyst used. Therefore, one skilled in the art would be able to select an appropriate temperature for activating the catalyst, for example, in the range of 200 to 400°C.

[0092] In various embodiments, the Fischer-Tropsch catalyst is activated by contact with H2 and CO. This may be particularly suitable when activation provides conversion to carbide, such as many iron-based catalysts. In various embodiments of the present disclosure described elsewhere herein, the reducing gas comprises at least a portion of the H2 and CO from the first product stream. For example, in some embodiments, the process further includes separating at least a portion of the H2 and at least a portion of the CO from the first product stream and contacting them with a Fischer-Tropsch catalyst to activate the Fischer-Tropsch catalyst. In process 200, as shown schematically in FIG. 3, at least a portion of the H2 and CO stream 227 is separated from first product stream 212 and contacts Fischer-Tropsch catalyst 223 to activate it. In other embodiments, H2 and CO present in the second feed stream can be used to activate the catalyst. The activation temperature can vary, for example, from 200 to 400°C.

[0093] As described above, the method includes contacting a Fischer-Tropsch catalyst with a second feed stream at a second temperature and a second pressure. One skilled in the art will select appropriate reaction conditions in conjunction with 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 150-400°C. For example, in various embodiments, the second temperature is in the range of 150-350°C, or 150-300°C, or 150-250°C, or 150-200°C, or 200-400°C, or 200-350°C, or 200-300°C, or 200-250°C, or 250-400°C, or 250-350°C, or 250-300°C, or 300-400°C. In some specific embodiments, the second temperature is in the range of 200-350°C.

[0094] In particular, in many embodiments, the first and second temperatures can be relatively close to one another. 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 suitable for, or at least close to, the Fischer-Tropsch reaction step. This can desirably provide increased process integration. For example, in various embodiments, the first temperature is within 100°C of the second temperature, e.g., within 50°C of the second temperature, or within 25°C of the second temperature.

[0095] 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, e.g., 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 a number of 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.

[0096] In some embodiments of the present disclosure described herein, the second pressure is in the range of 10 to 50 barg. For example, in various embodiments, the second pressure is in the range of 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 is in the range of 20 to 50 barg.

[0097] The Fischer-Tropsch process described herein can be carried out at a variety of GHSV (gas hourly space velocity) values, as will be understood by those skilled in the art. Thus, the GHSV for carrying out the Fischer-Tropsch reaction is not particularly limited. For example, in some embodiments of the present disclosure, the process 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 process for conducting the reverse water gas shift reaction is carried out at a GHSV ranging from 1,000 to 1,200,000 h, or from 1,000 to 500,000 h, or from 1,000 to 100,000 h, or from 5,000 to 1,200,000 h, or from 5,000 to 500,000 h, or from 5,000 to 100,000 h, or from 10,000 to 1,200,000 h, or from 10,000 to 500,000 h, or from 10,000 to 100,000 h. In various embodiments of the present disclosure, the process for conducting a Fischer-Tropsch reaction is conducted at a GHSV ranging from 1,000 to 50,000 h, or from 2,000 to 50,000 h, or from 5,000 to 50,000 h, or from 10,000 to 50,000 h, or from 1,000 to 40,000 h, or from 2,000 to 40,000 h, or from 5,000 to 40,000 h, or from 10,000 to 40,000 h, or from 1,000 to 30,000 h, or from 2,000 to 30,000 h, or from 5,000 to 30,000 h, or from 10,000 to 30,000 h.

[0098] 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 present disclosure described herein, contacting the Fischer-Tropsch catalyst with the second feed stream to provide the second product stream is carried out at a C5+ selectivity (i.e., relative to all C5+ species) of at least 30%, e.g., at least 50%, or at least 70%. For example, in some embodiments, the selectivity to C5+ alkanes is at least 30%, e.g., at least 50%, or at least 70%. In some embodiments, the selectivity to C5+ alkanes and C5+ alcohols is at least 30%, e.g., at least 50%, or at least 70%.

[0099] Additional components may be present in the second product stream. For example, in some embodiments, the second product stream includes water, another product of the Fischer-Tropsch reaction. One or more light hydrocarbons (i.e., C1-C4) may also be present as by-products. CO and / or H2 may be present, for example, as unreacted products from the second feed stream. CO2 or other inert materials described herein may also be present. Such components of the second product stream can be separated and / or recycled in various ways.

[0100] For example, in various embodiments, the method further includes separating at least a portion of the water from the second product stream. This is shown schematically in FIG. 4. In the embodiment of FIG. 4, the reverse 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 reverse 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 reverse water gas shift catalyst 313 to provide the first product stream 312, which is sent directly to the Fischer-Tropsch catalyst 323 as the second feed stream 321 to provide the 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 the water from the second product stream 322 to provide a water-containing stream 334.

[0101] While light hydrocarbons are often not a desired portion of a Fischer-Tropsch product used as a fuel or lubricant, they are useful for many purposes in their own right. Accordingly, in various embodiments, the method further includes separating at least a portion of the 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 process 200 of FIG. 3, the light hydrocarbons can be provided as part of recycle stream 236, which becomes part of second feed stream 221. In process 300 of FIG. 4, the light hydrocarbons can be provided as part of recycle stream 336, which becomes part of first feed stream 311. In process 400 of FIG. 5, the light hydrocarbons are recycled to first feed stream 411 via recycle stream 442.

[0102] 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 process is shown schematically in Figure 5, where process 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 elsewhere herein. Here, the process includes oxidizing at least a portion of a light hydrocarbon stream 450 in a partial oxidation reaction zone 452 to provide a pOX stream containing CO and / or CO2, and including at least a portion of the pOX stream 454 in a first feed stream 411 and / or a second feed stream 421.

[0103] Other methods can be used to provide CO and / or CO from the light hydrocarbon stream. For example, reforming techniques such as steam reforming and autothermal reforming can be used to provide CO by reaction of 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 CO 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.

[0104] Additionally, 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 process includes combusting at least a portion of the light hydrocarbon stream to provide energy, such as thermal energy or electrical energy. For example, in process 400 of FIG. 5 , a portion of light hydrocarbon stream 450 is combusted in a power generation zone (here, generator 470) to generate electrical stream 472. In various embodiments, the thermal energy may be used to provide the heat load required for a reverse water gas shift process. For example, in process 400 of FIG. 5 , a portion of light hydrocarbon stream 450 is combusted in a power generation zone (here, heat generator 480) to generate heat stream 482. Heat stream 482 is directed to heat exchange zone 490 to heat first feed stream 411. Thermal energy can similarly be supplied to a Fischer-Tropsch reaction. As one skilled in the art will also appreciate, other treatments of light hydrocarbon streams (e.g., partial oxidation) can also provide energy, which can be used, for example, as described herein.

[0105] Similar to the first product stream, heat can be exchanged from the second product stream to, for example, supply heat 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 process 300 of FIG. 4 , 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. 5, heat is exchanged between at least a portion of the second product stream 422 and the second feed stream 421 in 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 appreciate that a wide variety of heat exchangers can be used for this purpose.

[0106] Of course, any excess heat in the second product stream may additionally or alternatively be used for other purposes. For example, in various embodiments, the process 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. 4 , where, after heat exchange with the first feed stream 311, the second product stream 322 is directed to a 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).

[0107] It may be desirable to recycle hydrogen from the second product stream, for example, to the first feed stream and / or the second feed stream. For example, in various embodiments, the process includes recycling at least a portion of the H of the second product stream to the second feed stream. For example, in the process of FIG. 3, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the H 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 H of the second product stream to the first feed stream. For example, in the process of FIG. 4, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the H of the second product stream can be recycled to the first feed stream 311 via recycle stream 336. In various embodiments, at least 25%, e.g., at least 50%, of the H of the second product stream is recycled to the first feed stream or the second feed stream. In various embodiments, at least 75%, eg, at least 90%, of the H2 of the second product stream is recycled to the first feed stream or the second feed stream.

[0108] In some cases, for example, when H2 is provided to the second feed stream from a source other than the first product stream, the H2 from the second product stream can constitute a majority of the H2 of the first feed stream, e.g., at least 90%, at least 95%, or at least 98% of the H2 of the first feed stream. This is shown, for example, in Figure 5, where the primary H2 input to the process is through stream 440, which becomes part of second feed stream 421. H2 from the second product stream is included in recycle stream 442, which becomes part of first feed stream 411.

[0109] Similarly, it may be desirable to recycle the CO of the second product stream, for example, to the first feed stream and / or the second feed stream. For example, in various embodiments, the process includes recycling at least a portion of the CO of the second product stream to the second feed stream. For example, in the process 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 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 process of FIG. 4, 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%, e.g., 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%, e.g., at least 90%, of the CO of the second product stream is recycled to the first feed stream or the second feed stream.

[0110] In many cases, both the CO and H2 of the second product stream are recycled.

[0111] Additionally, if one or more inerts are used in a Fischer-Tropsch process step, it may be desirable to recycle them. For example, in various embodiments, the process includes recycling at least a portion of the inerts of the second product stream to the second feed stream. For example, in the process of FIG. 3, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the inerts of the second product stream can be recycled to the second feed stream 221 via recycle stream 236. In various embodiments, the process includes recycling at least a portion of the inerts of the second product stream to the first feed stream. For example, in the process of FIG. 4, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the inerts of the second product stream can be recycled to the first feed stream 311 via recycle stream 336. In various embodiments, at least 25%, e.g., at least 50%, of the inerts of the second product stream are recycled to the first feed stream or the second feed stream. In various embodiments, at least 75%, e.g., at least 90%, of the inerts of the second product stream are recycled to the first feed stream or the second feed stream. In various embodiments, a purge stream can be incorporated with the recycle stream to prevent uncontrolled accumulation of inerts in the recycle stream (not shown here).

[0112] Specifically, because CO is a carbon source in the reverse water gas shift process step, it may be particularly desirable to recycle CO to the first feed stream. Accordingly, in various embodiments, the process includes recycling at least a portion (e.g., at least 50%, at least 75%, or at least 90%) of the CO of the second product stream to the first feed stream. For example, in the process of Figure 4, at least a portion (e.g., at least 50%, at least 75%, or at least 90%) of the CO of the second product stream may be recycled to the first feed stream 311 via recycle stream 336.

[0113] In some cases, for example, when CO is provided to the second feed stream from a CO source other than the first product stream, the CO from the second product stream can constitute a majority of the CO of the first feed stream, e.g., at least 90%, at least 95%, or at least 98% of the CO of the first feed stream. This is shown, for example, in Figure 5, where the primary CO input to the process is through stream 440, which becomes part of second feed stream 421. The CO of the second product stream is included in recycle stream 442, which becomes part of first feed stream 411.

[0114] As described above, the Fischer-Tropsch process step provides a second product stream containing C5+ hydrocarbons (e.g., unsubstituted hydrocarbons such as alkanes and alkenes, and / or oxygenated hydrocarbons such as alcohols). Accordingly, in various embodiments, one or more products are provided from at least a portion of the C5+ hydrocarbons of the second product stream. The C5+ hydrocarbons can be used as the basis for various fuels, such as gasoline, diesel, and aviation fuel. Other products, such as waxes and lubricants, can also be produced. Additionally, the alkenes and oxygenates can be used as feedstocks in various other processes.

[0115] Those skilled in the art will use conventional post-processing techniques to convert the C5+ hydrocarbon-containing product into desired products, such as a desired fuel. For example, in various embodiments, the method further includes hydrotreating at least a portion of the C5+ hydrocarbons of the second product stream. As will be understood by those skilled 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 those skilled in the art will apply them herein. For example, in process 300 of Figure 4, second product stream 322 is hydrotreated in hydrotreating reactor 350 to provide hydrotreated product stream 352.

[0116] As noted above, CO and H are substantial inputs to the claimed process. Advantageously, the inventors recognize that each of these can come from renewable or other environmentally responsible sources.

[0117] 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 lower in carbon intensity. Accordingly, in some embodiments of the present disclosure described herein, at least a portion of the CO2 in the first feed stream and / or the second feed stream is 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 plant. Thus, the integrated rWGS-Fischer-Tropsch process of the present 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 for decarbonizing transportation fuels, especially for both the automotive and aviation sectors, since the carbon monoxide produced in the rWGS reaction can be easily utilized by established techniques for synthesizing liquid hydrocarbon fuels by the Fischer-Tropsch process.

[0118] Similarly, H2 can be provided from environmentally responsible sources. In some embodiments, at least a portion of the H2 of the first feed stream and / or the second feed stream is from a renewable source. For example, in various embodiments, at least a portion (e.g., at least 25%, at least 50%, or at least 75%) of the H2 of the first feed stream and / or the second feed stream can be so-called "green" hydrogen, e.g., produced from 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 of the first feed stream and / or the second feed stream can be from so-called "blue" sources, e.g., from a natural gas reforming process with carbon capture. Of course, other H2 sources can be used, partially or completely. 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.

[0119] The inventors have noted that water electrolysis is a desirable method for providing hydrogen to the claimed process. Accordingly, in some embodiments, the method includes providing at least a portion of H to the first feed stream and / or the second feed stream by water electrolysis. 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, water electrolysis is performed at least in part using electricity generated according to the processes described herein. For example, in process 200 of FIG. 3, 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. H generated in the electrolysis is provided to the first feed stream via stream 265. In some embodiments, at least a portion of the O produced in the electrolysis is provided to the partial oxidation reaction zone, as described herein and shown in the embodiment of FIG. 7. Hydrogen from electrolysis can also be combusted to provide thermal energy, for example, which can be used to heat the first feed stream.

[0120] The processes described herein can be operated in a wide variety of reactor systems. In some embodiments, the first reaction zone (i.e., where the reverse water gas shift process step occurs) comprises a first reactor containing a reverse water gas shift catalyst, and the second reaction zone (i.e., where the Fischer-Tropsch process step occurs) comprises a second reactor containing a Fischer-Tropsch catalyst. Examples of such processes are shown schematically in Figures 1, 2, and 4. In these examples, the processes (100, 200, 400) are carried out in reactor systems including a first reactor (110, 210, 410) containing a reverse water gas shift catalyst (113, 213, 413) and a second reactor (120, 220, 420) containing a Fischer-Tropsch catalyst (123, 223, 423). The reactors used in the integrated processes of the present disclosure described herein are not particularly limited, and one of ordinary skill in the art can select an appropriate reactor.

[0121] However, other embodiments are possible. For example, in some embodiments, the process is carried out in a reactor system including a first catalyst bed containing a reverse water gas shift catalyst, and the second reaction zone includes a second catalyst bed containing a Fischer-Tropsch catalyst. In some embodiments, the first and second reactor beds are located within the same reactor. Such a configuration is shown in FIG. 4, where the reverse water gas shift catalyst 313 is located in the first catalyst bed 314 and the Fischer-Tropsch catalyst 323 is located in the second catalyst bed 324. Here, the catalyst beds 314 and 324 are located within the same reactor 305, with the process gas flowing between them. Such a configuration is particularly desirable when the first and second temperatures are relatively close to each other.

[0122] In various embodiments, the process is carried out in a reactor system including one or more first catalyst vessels containing a reverse water gas shift catalyst, and the second reaction zone includes one or more second catalyst vessels containing a Fischer-Tropsch catalyst, which may be provided within the same reactor, as described above with respect to catalyst beds.

[0123] As noted above, the reverse water gas shift process steps and Fischer-Tropsch process steps using the platinum, palladium, and / or gold catalysts described herein can be carried out under similar conditions. Accordingly, in various embodiments, the reverse water gas shift catalyst and the Fischer-Tropsch catalyst can be provided together in the same catalyst bed, e.g., mixed together. Such an embodiment is shown in FIG. 6 , where process 500 is carried out in a reactor system including reactor 505, in which reverse water gas shift catalyst 513 and Fischer-Tropsch catalyst 523 are mixed together in a single catalyst bed 524. Here, first feed stream 511 and second product stream 522 can be substantially as described herein. The first product stream and second feed stream are understood to be a mixture of process gases within the mixed catalyst.

[0124] In particular in the above-described embodiments, separate rWGS catalysts and Fischer-Tropsch catalysts may be used, for example, in separate reactors, in separate zones of the same reactor, or even mixed in the same zone of the reactor.

[0125] However, the inventors also note that there are certain commonalities between the rWGS catalysts described herein and certain Fischer-Tropsch catalysts. For example, as those skilled in the art will appreciate, manganese is a common modifier used in Fischer-Tropsch catalysts, particularly cobalt-based catalysts. The inventors also note that similar supports may be used for each.

[0126] Therefore, in addition to the above configurations, the present 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 catalytic metal and a Fischer-Tropsch-active catalytic metal in the same body. Those skilled in the art will understand that both the rWGS catalyst and the Fischer-Tropsch catalyst can be supported catalysts, e.g., metal oxide-supported catalysts. Thus, in various embodiments of the present disclosure, the rWGS-active catalytic metal and the Fischer-Tropsch-active catalytic metal can be provided together on the same support to provide the bifunctional catalyst. For example, in some embodiments, the support for the bifunctional catalyst itself is provided as a separate body of material, such as a porous particle, pellet, or shaped extrudate, on which the rWGS-active catalytic metal and the FT-active catalytic metal are provided to provide the bifunctional catalyst. The rWGS-active catalytic metal and the FT-active catalytic 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 may itself be formed as a layer on an underlying substrate. For example, in some embodiments, the bifunctional catalyst is formed from a layer of rWGS-active catalytic metal and a layer of FT-active catalytic metal on the underlying substrate. The rWGS-active catalytic metal and the FT-active catalytic metal may be uniformly distributed on the underlying substrate. In other embodiments, the rWGS-active catalytic metal and the FT-active catalytic metal may be in separate regions on the underlying substrate. The underlying substrate is not particularly limited. It may be formed, for example, from a metal or metal oxide and may itself be provided in many forms, such as particles, pellets, shaped extrudates, or monoliths.

[0127] The bifunctional catalyst comprises a support material, a rWGS-active catalytic metal described herein, and a Fischer-Tropsch-active catalytic metal described herein. For example, the bifunctional catalyst comprises a support that is a metal oxide support described herein, at least one of platinum, palladium, and gold, manganese, and at least one of cobalt, iron, rhodium, and ruthenium. In some embodiments of the present disclosure, the bifunctional catalyst comprises a support that is a metal oxide support described herein, at least one of platinum, palladium, and gold, manganese, and cobalt. In some embodiments of the present disclosure, the bifunctional catalyst comprises a support that includes at least one of titanium oxide, zirconium oxide, cerium oxide, or aluminum oxide, at least one of platinum, palladium, and gold, manganese, and cobalt. In some embodiments, the bifunctional catalyst comprises a titanium oxide support, at least one of platinum, palladium, and gold, manganese, and cobalt. In some embodiments, the bifunctional catalyst comprises a titanium oxide support, platinum, manganese, and cobalt. In some embodiments, the bifunctional catalyst comprises a titanium oxide support, palladium, manganese, and cobalt. In some embodiments, the bifunctional catalyst comprises a titanium oxide support, gold, manganese, and cobalt. For example, in some embodiments, the bifunctional catalyst comprises a titanium oxide support, at least one of platinum, palladium, and gold present in an amount ranging from 0.05 to 10 wt%, manganese present in an amount ranging from 0.5 to 20 wt%, and cobalt present in an amount ranging from 7 to 25 wt%. In some embodiments, the bifunctional catalyst comprises a titanium oxide support, platinum present in an amount ranging from 0.05 to 10 wt%, manganese present in an amount ranging from 0.5 to 20 wt%, and cobalt present in an amount ranging from 7 to 25 wt%. In some embodiments, the bifunctional catalyst comprises a titanium oxide support, palladium present in an amount ranging from 0.05 to 10 wt %, manganese present in an amount ranging from 0.5 to 20 wt %, and cobalt present in an amount ranging from 7 to 25 wt %.In some embodiments, the bifunctional catalyst comprises a titanium oxide support, gold present in an amount ranging from 0.05 to 10 wt %, manganese present in an amount ranging from 0.5 to 20 wt %, and cobalt present in an amount ranging from 7 to 25 wt %.

[0128] The ratio of the rWGS-active catalytic metal to the FT-active catalytic metal in the bifunctional catalyst is not particularly limited, and those skilled in the art can select an appropriate ratio. For example, in some embodiments, the ratio of the rWGS-active catalytic metal to the FT-active catalytic metal in the bifunctional catalyst is at least 0.1:1. In various embodiments, the ratio of the rWGS-active catalytic metal to the FT-active catalytic metal in the bifunctional catalyst is at least 0.2:1, or 0.5, or 1:1.

[0129] Such catalysts may be used in embodiments such as those described with respect to Figure 6. One skilled in the art will select reaction conditions that provide an appropriate balance of reverse water gas shift activity and Fischer-Tropsch activity.

[0130] 7 is a schematic diagram of another integrated process according to the present disclosure, in which the reverse water gas shift and Fischer-Tropsch process steps are integrated together with the partial oxidation of light hydrocarbons to provide CO and H for the Fischer-Tropsch process step, electrolysis to provide H for the reverse water gas shift process step and O for the partial oxidation, and various recycles and optional feeds as described throughout this specification.

[0131] One skilled in the art will, based on the above general disclosure and with reference to the following examples, provide the materials and practice the processes described herein. [Example]

[0132] The following examples illustrate specific embodiments of the catalysts and processes of the present disclosure, as well as various uses thereof. They are provided for illustrative purposes only and should not be construed as limiting the scope of the present disclosure.

[0133] Example 1. Modeling We modeled various equilibrium conditions for the reverse water-gas shift reaction. The predicted carbon dioxide conversion and product composition of the rWGS reaction (Equation 1), which competes with the Sabatier reaction (Equation 3) and the CO methanation reaction (Equation 4), were calculated over a temperature range of 400 to 800 °C based on thermodynamic equilibrium. From the modeling, carbon monoxide selectivity increased at temperatures above 600 °C, while methane selectivity decreased at higher temperatures.

[0134] These results clearly show that the Sabatier reaction (Equation (3)) and CO methanation (Equation (4)) side reactions are exothermic and favored at low temperatures, while the rWGS reaction (Equation (1)) is endothermic and favored at high temperatures. However, other carbon-producing side reactions not accounted for in this example may occur at high temperatures. Therefore, we investigated catalysts that operate at intermediate temperatures. These catalysts are discussed in more detail below.

[0135] Example 2. Preparation of catalyst The catalysts were prepared using a conventional impregnation process before being tested for their catalytic effectiveness in the reverse water gas shift reaction. The supports used are listed in Table 1.

[0136] [Table 1]

[0137] To prepare the catalysts, solutions of active metals (e.g., Pd, Pt, or Au) and manganese acetate tetrahydrate (99.9% purity, Fisher Chemicals) were prepared in deionized water. For platinum-containing solutions, a platinum(II) nitrate solution with 17.5 wt% Pt and 99.95% purity from Umicore was used. For palladium-containing solutions, a palladium(II) nitrated solution with 23.9 wt% Pd and 99.95% metal purity from Umicore was used. For gold-containing solutions, gold(III) hydroxide (79.1% Au measured after reduction with hydrazine dihydrate) from Sigma-Aldrich was used. The active metal salt and manganese solutions were added to the support powder. The amount of support added was based on the amount of water by mass, with a water:support ratio of 3:1. The slurry was then stirred at room temperature for 4 hours. Excess water was then evaporated using a stirred dry bath at a temperature of 60 °C. The resulting catalyst precursor powder was then dried in a drying oven at 90° C. for 24 hours.

[0138] The catalyst precursor powder was then subjected to calcination by uniformly spreading the powder in a crucible. The crucible was placed in a calcination furnace, and the temperature was increased from ambient temperature to 120°C at a rate of 10°C per minute. The temperature was then held at 120°C for 1 hour, and then increased from 120°C to 500°C at a rate of 2°C per minute. The temperature was held at 500°C for 4 hours, and then cooled to ambient temperature. The resulting catalyst was then tested for its viability for the reverse water gas shift reaction.

[0139] Example 3. Performance of platinum and palladium catalysts The catalysts prepared by the methods described herein were then tested for their catalytic performance in the reverse water gas shift reaction. The catalysts were ceria-supported catalysts containing either 0.25 wt%, 0.5 wt%, or 2 wt% platinum or palladium, and either 0 wt%, 1 wt%, or 5 wt% manganese. To test the catalytic performance of these catalysts, 20 μL of catalyst diluted with SiC F100 to provide a 1:10 ratio was loaded into a 3 mm ID ceramic tube reactor, resulting in a 0.22 mL catalyst bed with a zone height of 31.1 mm. Prior to conducting the rWGS reaction, the catalyst was activated at 590 °C for 5 hours in a 97% hydrogen and 3% argon atmosphere. The catalyst was then contacted with a feed stream containing H2 and CO2 in a 2:1 ratio at a temperature of 600 °C. The total pressure was maintained at 30 barg. For Tests 1-2, 4, and 6-8, the GHSV was maintained at 29,500 h-1, while for Tests 3 and 5, the GHSV was maintained at 1,200,000 h-1. The catalytic performance was analyzed by detecting the gas composition of the reactor outlet feed using a multi-detector gas chromatograph. The catalytic performance of these catalysts is shown in Table 2. In Table 2 and the following Tables 3-7, the amount of platinum, palladium, and / or manganese present in the catalyst is shown in parentheses. These values are in weight percent and are based on the total weight of the catalyst. For example, CeO2Pt(0.5)Mn(1) corresponds to a catalyst with 0.5 wt% Pt, 1 wt% Mn, and 98.5 wt% CeO2.

[0140] [Table 2]

[0141] Catalysts containing 0.5 wt % platinum or palladium exhibit very high CO selectivity, and the addition of manganese to the catalyst increases both catalytic activity and CO selectivity.

[0142] To further investigate these catalysts, the CeO2Pd(0.5)Mn(5), CeO2Pd(0.5)Mn(1), CeO2Pt(0.5)Mn(1), and CeO2Pt(0.5)Mn(5) catalysts were also tested at different temperatures and pressures. Tests 9–20 were conducted at a 2:1 H2:CO2 molar ratio and a GHSV of 16,000 h-1, while Test 21 was conducted at a 2:1 H2:CO2 molar ratio and a GHSV of 1,200,000 h-1. These results are shown in Table 3.

[0143] [Table 3]

[0144] As shown in Table 3, the catalyst exhibits excellent CO selectivity, which remains consistent over the range of process conditions tested. The high CO selectivity demonstrated in the above tests provides an effluent stream suitable for integration with other processes.

[0145] Example 4. Effect of manganese on ceria-supported platinum catalysts To investigate the effect of manganese on supported reverse water gas shift catalysts, ceria-supported platinum catalysts with and without manganese were measured. Platinum was present in the catalysts at concentrations of 0.1 wt%, 0.5 wt%, or 1 wt%, with or without manganese present at 5 wt%. Ceria itself, as well as a 5 wt% manganese catalyst on ceria without platinum, were also measured. These catalysts were prepared by the method described herein. To test the catalytic performance of these catalysts, a Meryer quartz reactor was used with 0.1 g of catalyst at a concentration of approximately 2 g / mL. A total flow rate of 37.7 mL / min (9.6 mol% CO partial pressure, H partial pressure variation for different H:CO ratios, equilibrated with Ar) was used. These catalysts were then contacted with a feed stream of H and CO present in a 3:1 molar ratio at two different temperatures, under 1 bar pressure, and a GHSV of 34,560 h. The catalyst performance was analyzed by detecting the gas composition of the reactor outlet feed using a multi-detector gas chromatograph, and the results are shown in Table 4.

[0146] [Table 4]

[0147] Table 4 shows that one route to increasing catalytic activity is by increasing the platinum loading. However, this is accompanied by a decrease in CO selectivity. When up to 5 wt.% manganese without platinum is placed on the supported catalyst, there is a loss of activity, but CO can be recovered to over 99% under the conditions tested. However, when 0.1 wt.% to 1 wt.% platinum is added to the 5 wt.% manganese on ceria catalyst, an increase in CO selectivity and CO conversion is observed, as shown in Table 4. Some loss in catalytic activity is accompanied by a large increase in CO selectivity. However, without being bound by theory, the inventors believe that the decrease in conversion may be due to less methanation occurring.

[0148] To further investigate the effect of ceria-supported manganese catalysts containing 0.5 wt.% or 1 wt.% platinum, with and without 5 wt.% manganese, they were contacted with feed streams having high H:CO ratios at two different temperatures. These tests were conducted at a pressure of 1 barg and a GHSV of 2250 h. Table 5 reports the results.

[0149] [Table 5]

[0150] Table 5 shows that the presence of Mn in the catalyst maintains CO selectivity even at very high H:CO ratios. When using catalysts with manganese and platinum or palladium supported on ceria, CO selectivity is observed to remain robust with values above 99%, as shown in Table 5.

[0151] Example 5. Effect of the support on catalyst performance The effect of the support on catalytic performance was also evaluated by evaluating platinum and manganese supported catalysts on various catalyst supports (ceria, alumina, and titania). These catalysts contained 0.5 wt. % platinum and 5 wt. % manganese. As in the previous examples, these catalysts were prepared by the methods described herein. The reactor setup and catalyst activation described in Example 4 were also used here. These catalysts were then contacted with a feed stream of H2 and CO2 present in a 3:1 molar ratio at two different temperatures, under a pressure of 1 barg, and a GHSV of 34,560 h-1. Catalyst performance was analyzed by detecting the gas composition of the reactor outlet feed using a multi-detector gas chromatograph. The results are shown in Table 6.

[0152] [Table 6]

[0153] Table 6 shows that the effect of manganese remains viable across a range of supports for platinum catalysts. Addition of 5 wt. % manganese to various metal oxide supports (alumina, praseodymium-doped ceria, titania, and ceria) loaded with 0.5 wt. % platinum reduces catalytic activity but increases CO selectivity. As discussed above with respect to the results shown in Table 4, without being bound by theory, the inventors believe that the reduced conversion may be due to less methanation occurring.

[0154] Example 6. Methane selectivity of ceria-supported platinum catalysts The catalysts prepared by the methods described herein were then tested for their methane selectivity for the reverse water gas shift reaction. These catalysts were ceria-supported catalysts containing 0.5 wt.% platinum and either 0 wt.%, 1 wt.%, or 5 wt.% manganese. The catalysts were contacted with a feed stream containing 6 vol.% H2 and 2 vol.% CO2. The GHSV was 1200 h-1. The amount of catalyst used was 50 mg. The carbon dioxide conversion and carbon molar selectivity for methane were followed over a temperature range from 200 °C to 700 °C.

[0155] Figure 8 shows the CO conversion for the equilibrium conversion of CO to CO, along with the reaction conversion for the following catalysts: CeO2Pt(0.5), CeO2Pt(0.5)Mn(1), and CeO2Pt(0.5)Mn(5). Figure 9 shows the carbon molar selectivity of methane for the three catalysts. From Figure 8, it can be seen that the presence of the CeO2Pt(0.5) catalyst reduces the CO conversion relative to the equilibrium conversion at temperatures below 375 °C, and the inclusion of manganese further reduces the conversion. However, without being bound by theory, the inventors believe that the reduced conversion may be due to less methanation occurring, as shown in Figure 9. The results suggest that the inclusion of 1 wt% or 5 wt% manganese can modify product selectivity, for example, by reducing methane selectivity. For example, as shown in Figure 9, the addition of manganese to a ceria-supported platinum catalyst reduced methane conversion from 11% to 0% at 500°C.

[0156] Example 7. Methane selectivity of titania-supported platinum catalysts The catalysts prepared by the methods described herein were then tested for their methane selectivity for the reverse water gas shift reaction. These catalysts were titania-supported catalysts containing 0.5 wt.% platinum and either 0 wt.%, 1 wt.%, or 5 wt.% manganese. The catalysts were contacted with a feed stream containing 6 vol.% H2 and 2 vol.% CO2. The GHSV was 1200 h-1. The amount of catalyst used was 50 mg. The carbon dioxide conversion and carbon molar selectivity for methane were followed over a temperature range from 200 °C to 700 °C.

[0157] Figure 10 shows the CO conversion for the equilibrium conversion of CO to CO using the TiO2Pt(0.5), TiO2Pt(0.5)Mn(1), and TiO2PtMn(5) catalysts. Figure 10 shows the carbon molar selectivity for methane for the three catalysts. These results show similar effects to those shown in Figures 8 and 9. Activity shifts to higher temperatures at 1 wt% manganese and shifts further at 5 wt% manganese, with methane selectivity decreasing significantly at 1 wt% manganese and below the gas chromatographic detection limit at 5 wt% manganese.

[0158] Example 8. Methane selectivity of alumina-supported platinum catalysts The catalysts prepared by the methods described herein were then tested for their methane selectivity for the reverse water gas shift reaction. These catalysts were alumina-supported catalysts containing 0.5 wt.% platinum and 0 wt.%, 1 wt.%, or 5 wt.% manganese. The catalysts were contacted with a feed stream consisting of 6 vol.% H2 and 2 vol.% CO2. The GHSV was 1200 h-1. The amount of catalyst used was 50 mg catalyst. The carbon dioxide conversion and carbon molar selectivity for methane were tracked over a temperature range from 200 °C to 700 °C and are shown in Figures 9 and 10, respectively.

[0159] Figure 12 shows the CO conversion for the equilibrium conversion of CO to CO using the Al2O3Pt(0.5), Al2O3Pt(0.5)Mn(1), and Al2O3Pt(0.5)Mn(5) catalysts, and Figure 13 shows the carbon molar selectivity for methane for the three catalysts. These results show the same effect as shown in Figures 7-11. Activity shifts to higher temperatures with 1 wt% manganese and shifts further with 5 wt% manganese. Furthermore, methane selectivity decreases significantly with 1 wt% manganese. At 5 wt% manganese, methane selectivity decreases to 2%.

[0160] Example 9. Effect of catalyst activation on catalytic performance Catalysts prepared by the methods described herein were evaluated for the effect of catalyst activation on catalytic performance. A ceria-supported catalyst containing 0.5 wt.% platinum and 5 wt.% manganese was activated in a hydrogen atmosphere at three different temperatures (400°C, 590°C, and 760°C) and then used in the rWGS process. A 3 mm inner diameter ceramic tube reactor was filled with 20 μL of catalyst diluted 1:10 with SiC F100, resulting in a 0.22 mL catalyst bed with a zone height of 31.1 mm. Catalyst activation was carried out at a GHSV of 200,000 h-1 using pure H2. The reactor pressure was set to 10 barg, and the reactor was then heated at a rate of 1 K / min to the desired activation temperature and held at that temperature for 5 hours. After activation, the reactor was cooled to the temperature for the rWGS process. Four rWGS reaction temperatures were evaluated: 400°C, 500°C, 600°C, and 700°C. Once the rWGS reaction temperature was reached, the feed stream was introduced, followed by the reaction pressure. The activated catalyst was contacted with a feed stream of H2 and CO2 present in a 2:1 molar ratio at a pressure of 30 barg and a GHSV of 1,200,000 h-1. The catalyst performance was analyzed by detecting the gas composition of the reactor outlet feed using a multi-detector gas chromatograph. The results are shown in Table 7.

[0161] [Table 7]

[0162] The results in Table 7 show consistent CO selectivity and CO conversion regardless of activation temperature. Additionally, the results in Table 7 show that CO selectivity is high (above 98%) for all rWGS temperatures measured, but CO conversion increases with increasing reaction temperature. However, using higher activation temperatures and higher rWGS reaction temperatures appears to have a negative impact on catalyst activity, as seen in Test 70. Overall, the results in Table 7 indicate that activation temperature is another variable for adjusting the resulting product stream.

[0163] Example 10. Performance of Au catalyst The catalysts prepared by the methods described herein were then tested for their catalytic performance in the reverse water gas shift reaction. The catalysts tested were ceria-supported catalysts containing 0.5 wt% gold and 0, 1, or 5 wt% manganese. To test the catalytic performance of these catalysts, 20 μL of catalyst diluted with SiC F100 to provide a 1:10 ratio was loaded into a 3 mm ID ceramic tube reactor, resulting in a 0.22 mL catalyst bed with a zone height of 31.1 mm. Prior to conducting the rWGS reaction, the catalyst was activated at 590 °C for 5 h in a 97% hydrogen and 3% argon atmosphere. The catalyst was then contacted with a feed stream containing H2 and CO2 in a 2:1 ratio at 600 °C to conduct the rWGS reaction. The total pressure and GHSV were maintained at 30 barg and 29,500 h-1, respectively. Catalytic performance was analyzed by detecting the gas composition of the reactor outlet feed using a multi-detector gas chromatograph. The catalytic performance of these catalysts is shown in Table 8. In Tables 8 and 9-11 below, the amount of gold and / or manganese present in the catalyst is shown in parentheses. These values are in weight percent and are based on the total weight of the catalyst. For example, CeO2Au(0.5)Mn(1) corresponds to a catalyst having 0.5 wt% Au, 1 wt% Mn, and 98.5 wt% CeO2.

[0164] [Table 8]

[0165] The catalyst containing 0.5 wt. % gold exhibits very high selectivity, and the addition of 1 wt. % and 5 wt. % manganese to the catalyst leads to an increase in both catalytic activity and CO selectivity.

[0166] Catalysts containing 0.5 wt% gold and 0 and 5 wt% manganese were also tested at 500 °C, a 2:1 H2:CO2 ratio, a GHSV of 16,000 h-1, and two different pressures. These results are reported in Table 9.

[0167] [Table 9]

[0168] Table 9 shows that the ceria-supported manganese and gold catalysts exhibit very high CO selectivity at other operating conditions.

[0169] Example 11. Effect of manganese on ceria-supported gold catalysts To investigate the effect of manganese on supported reverse water gas shift catalysts, ceria-supported gold catalysts with and without manganese were measured under different temperatures and pressures. Gold was present in the catalyst at a concentration of 0.5 wt %, with or without manganese present at 5 wt %. These catalysts were prepared by the methods described herein. The reactor setup and catalyst activation described in Example 10 were also used here. For the rWGS reaction, Runs A-8 through A-13 were conducted at a 2:1 H:CO molar ratio and a GHSV of 29,500 h-1. Catalyst performance was analyzed by detecting the gas composition of the reactor outlet feed using a multi-detector gas chromatograph. The results are shown in Table 10.

[0170] [Table 10]

[0171] The results in Tables 9 and 10 show that the catalyst exhibits excellent CO selectivity, and the selectivity remains robust over the range of process conditions tested, especially at temperatures between 500°C and 700°C. The addition of 5 wt% manganese to the catalyst increases CO selectivity, with higher overall CO yields observed at 500°C and 600°C. A slight increase in CO selectivity is observed in Tests A10 and A11, which were performed at 700°C.

[0172] The CO selectivity of the supported gold catalyst is extremely high throughout the conditions tested. There is a general trend for the CeO2Au(0.5)Mn(5) catalyst to be more selective than the manganese-free ceria-supported gold catalyst. This suggests that including manganese in the formulation is beneficial for CO selectivity. Most importantly, carbon monoxide selectivity does not decrease as the pressure increases from 12 to 20 barg. This is important because methanation activity typically increases when operating at higher pressures, typically resulting in lower CO selectivity. Operating further away from equilibrium can be helpful in this situation as well.

[0173] Example 12. Au catalyst performance at low temperatures The performance of the CeO2Au(0.5)Mn(5) catalyst was evaluated at lower temperatures and different H2:CO2 ratios. The catalyst was prepared by the method described herein, and the reactor setup and catalyst activation were used as described in Example 10. For the rWGS reaction, Tests A14-A16 were conducted at a pressure of 10 barg, and Test A17 was conducted at 20 barg. All tests were conducted at a GHSV of 16,000 h-1. Catalyst performance was analyzed by detecting the gas composition of the reactor outlet feed using a multi-detector gas chromatograph. The results are shown in Table 11.

[0174] [Table 11]

[0175] The catalyst exhibits high CO selectivity under the conditions tested in Table 11. Under the conditions used, the catalyst provides an effluent stream suitable for integration with other processes. Further aspects of the present disclosure are provided by the embodiments listed below, which may be combined in any number and in any combination not logically or technically consistent.

[0176] Embodiment 1. A supported reverse water gas shift catalyst comprising: a support which is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support comprising a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; at least one of platinum, palladium, and gold present in an amount ranging from 0.05 to 10 weight percent of the catalyst, based on the total weight of the catalyst; and and manganese present in an amount ranging from 0.5 to 20 weight percent of the catalyst, based on the total weight of the catalyst. Embodiment 2. The catalyst of embodiment 1, wherein the support comprises at least 70% by weight (e.g., at least 75%, or 80%, or 85%, or 90% by weight) of the catalyst on an oxide basis. Embodiment 3. The catalyst of embodiment 1 or embodiment 2, wherein the support is a cerium oxide support. Embodiment 4. The catalyst of embodiment 3, wherein at least one surface layer of the cerium oxide support comprises, on an oxide basis, at least 60% by weight cerium oxide, e.g., at least 70% by weight cerium oxide, or at least 80% by weight cerium oxide. Embodiment 5. The catalyst of embodiment 3, wherein at least the surface layer of the cerium oxide support comprises, on an oxide basis, at least 90% by weight cerium oxide, e.g., at least 95% by weight cerium oxide, or at least 98% by weight cerium oxide. Embodiment 6. The catalyst of any one of embodiments 3-5, wherein the cerium oxide support comprises, on an oxide basis, at least 50% by weight cerium oxide, e.g., at least 60% by weight cerium oxide, or at least 70% by weight cerium oxide, or at least 80% by weight cerium oxide. Embodiment 7. The catalyst of any one of embodiments 3-5, wherein the cerium oxide support comprises, on an oxide basis, at least 90% by weight cerium oxide, e.g., at least 95% by weight cerium oxide, or at least 98% by weight cerium oxide. Embodiment 8. The catalyst of embodiment 1 or embodiment 2, wherein the support is a titanium oxide support. Embodiment 9. The catalyst of embodiment 8, wherein at least the surface layer of the titanium oxide support comprises, on an oxide basis, at least 60% by weight titanium oxide, e.g., at least 70% by weight titanium oxide, or at least 80% by weight titanium oxide. Embodiment 10. The catalyst of embodiment 8, wherein at least one surface layer of the titanium oxide support comprises, on an oxide basis, at least 90% by weight titanium oxide, e.g., at least 95% by weight titanium oxide, or at least 98% by weight titanium oxide. Embodiment 11. The catalyst of any one of embodiments 8 to 10, wherein the titanium oxide support comprises, on an oxide basis, at least 50% by weight titanium oxide, e.g., at least 60% by weight titanium oxide, or at least 70% by weight titanium oxide, or at least 80% by weight titanium oxide. Embodiment 12. The catalyst of any one of embodiments 8 to 10, wherein the titanium oxide support comprises, on an oxide basis, at least 90% by weight titanium oxide, e.g., at least 95% by weight titanium oxide, or at least 98% by weight titanium oxide. Embodiment 13. The catalyst of embodiment 1 or embodiment 2, wherein the support is an aluminum oxide support. Embodiment 14. The catalyst of embodiment 13, wherein at least a surface layer of the aluminum oxide support comprises, on an oxide basis, at least 60 wt. % aluminum oxide, e.g., at least 70 wt. % aluminum oxide, or at least 80 wt. % aluminum oxide. Embodiment 15. The catalyst of embodiment 13, wherein at least a surface layer of the aluminum oxide support comprises, on an oxide basis, at least 90% by weight aluminum oxide, e.g., at least 95% by weight aluminum oxide, or at least 98% by weight aluminum oxide. Embodiment 16. The catalyst of any of embodiments 13-15, wherein the aluminum oxide support comprises, on an oxide basis, at least 50 wt. % aluminum oxide, e.g., at least 60 wt. % aluminum oxide, or at least 70 wt. % aluminum oxide, or at least 80 wt. % aluminum oxide. Embodiment 17. The catalyst of any of embodiments 13-15, wherein the aluminum oxide support comprises, on an oxide basis, at least 90% by weight aluminum oxide, e.g., at least 95% by weight aluminum oxide, or at least 98% by weight aluminum oxide. Embodiment 18. The catalyst of embodiment 1 or embodiment 2, wherein the support is a zirconium oxide support. Embodiment 19. The catalyst of embodiment 18, wherein at least the surface layer of the zirconium oxide support comprises, on an oxide basis, at least 60 wt. % zirconium oxide, e.g., at least 70 wt. % zirconium oxide or at least 80 wt. % zirconium oxide. Embodiment 20. The catalyst of embodiment 18, wherein at least the surface layer of the zirconium oxide support comprises, on an oxide basis, at least 90 wt. % zirconium oxide, e.g., at least 95 wt. % zirconium oxide, or at least 98 wt. % zirconium oxide. Embodiment 21. The catalyst of any of embodiments 18-20, wherein the zirconium oxide support comprises, on an oxide basis, at least 50 wt. % zirconium oxide, e.g., at least 60 wt. % zirconium oxide, or at least 70 wt. % zirconium oxide, or at least 80 wt. % zirconium oxide. Embodiment 22. The catalyst of any one of embodiments 18-21, wherein the zirconium oxide support comprises, on an oxide basis, at least 90 wt. % zirconium oxide, e.g., at least 95 wt. % zirconium oxide, or at least 98 wt. % zirconium oxide. Embodiment 23. The catalyst of embodiment 1 or embodiment 2, wherein the support is a mixed oxide support having at least one surface layer comprising at least 50% by weight, based on the oxides, of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide. Embodiment 24. The catalyst of any one of embodiments 1 to 23, wherein the support does not contain additional metals in a total amount of more than 2 wt. % additional metals, e.g., more than 1 wt. %, or more than 0.5 wt. %, on an oxide basis. Embodiment 25. The catalyst of any one of embodiments 1 to 23, wherein the support comprises at least one additional metal. Embodiment 26. The catalyst of embodiment 25, wherein the total amount of the at least one additional metal is in the range of 0.5 to 20 wt.%, e.g., 1 to 20 wt.%, or 2 to 20 wt.%, or 0.5 to 15 wt.%, or 1 to 15 wt.%, or 2 to 15 wt.%, or 0.5 to 10 wt.%, or 1 to 10 wt.%, or 2 to 10 wt.%, or 0.5 to 5 wt.%, or 1 to 5 wt.%, based on the oxide. Embodiment 27. The catalyst of any one of embodiments 1 to 26, wherein the support has a pore volume of at least 0.05 mL / g. Embodiment 28. The catalyst of any one of embodiments 1 to 27, wherein the support has a pore volume of at most 1.5 mL / g. Embodiment 29. The catalyst of any one of embodiments 1 to 28, wherein the support has a pore volume in the range of 0.05 to 1.5 mL / g. Embodiment 30. The catalyst of any one of embodiments 1 to 29, wherein platinum is present in the catalyst. Embodiment 31. The catalyst of embodiment 30, wherein platinum is present in the catalyst in an amount ranging from 0.1 to 10 wt. %, for example, from 0.5 to 10 wt. %, or from 1 to 10 wt. %, or from 2 to 10 wt. %, or from 5 to 10 wt. %, based on the total weight of the catalyst. Embodiment 32. The catalyst of embodiment 30, wherein platinum is present in the catalyst in an amount ranging from 0.05 to 7 wt.%, for example, from 0.1 to 7 wt.%, or from 0.5 to 7 wt.%, or from 1 to 7 wt.%, or from 2 to 7 wt.%, based on the total weight of the catalyst. Embodiment 33. The catalyst of embodiment 30, wherein platinum is present in the catalyst in an amount ranging from 0.05 to 5 wt.%, for example, from 0.1 to 5 wt.%, or from 0.5 to 5 wt.%, or from 1 to 5 wt.%, or from 2 to 5 wt.%, based on the total weight of the catalyst. Embodiment 34. The catalyst of embodiment 30, wherein platinum is present in the catalyst in an amount ranging from 0.05 to 2 wt. %, for example, from 0.1 to 2 wt. %, or from 0.3 to 2 wt. %, or from 0.5 to 2 wt. %, or from 1 to 2 wt. %, based on the total weight of the catalyst. Embodiment 35. The catalyst of embodiment 30, wherein platinum is present in the catalyst in an amount ranging from 0.05 to 1.5 wt. %, for example, from 0.1 to 1.5 wt. %, or from 0.3 to 1.5 wt. %, or from 0.5 to 1.5 wt. %, based on the total weight of the catalyst. Embodiment 36. The catalyst of embodiment 30, wherein platinum is present in the catalyst in an amount ranging from 0.05 to 1 wt. %, for example, from 0.1 to 1 wt. %, or from 0.3 to 1 wt. %, or from 0.5 to 1 wt. %, based on the total weight of the catalyst. Embodiment 37. The catalyst of embodiment 30, wherein platinum is present in the catalyst in an amount ranging from 0.05 to 0.8 wt %, for example, from 0.1 to 0.8 wt %, or from 0.3 to 0.8 wt %, or from 0.5 to 0.8 wt %, based on the total weight of the catalyst. Embodiment 38. The catalyst of any one of embodiments 1 to 37, wherein palladium is present in the catalyst. Embodiment 39. The catalyst of embodiment 38, wherein the palladium is present in the catalyst in an amount ranging from 0.1 to 10% by weight, for example, from 0.5 to 10% by weight, or from 1 to 10% by weight, or from 2 to 10% by weight, or from 5 to 10% by weight, based on the total weight of the catalyst. Embodiment 40. The catalyst of embodiment 38, wherein the palladium is present in the catalyst in an amount ranging from 0.05 to 7 wt.%, for example, from 0.1 to 7 wt.%, or from 0.5 to 7 wt.%, or from 1 to 7 wt.%, or from 2 to 7 wt.%, based on the total weight of the catalyst. Embodiment 41. The catalyst of embodiment 38, wherein the palladium is present in the catalyst in an amount ranging from 0.05 to 5 wt.%, for example, from 0.1 to 5 wt.%, or from 0.5 to 5 wt.%, or from 1 to 5 wt.%, or from 2 to 5 wt.%, based on the total weight of the catalyst. Embodiment 42. The catalyst of embodiment 38, wherein the palladium is present in the catalyst in an amount ranging from 0.05 to 2 wt. %, for example, from 0.1 to 2 wt. %, or from 0.3 to 2 wt. %, or from 0.5 to 2 wt. %, based on the total weight of the catalyst. Embodiment 43. The catalyst of embodiment 38, wherein the palladium is present in the catalyst in an amount ranging from 0.05 to 1.5 wt.%, for example, from 0.1 to 1.5 wt.%, or from 0.3 to 1.5 wt.%, or from 0.5 to 1.5 wt.%, based on the total weight of the catalyst. Embodiment 44. The catalyst of embodiment 38, wherein the palladium is present in the catalyst in an amount ranging from 0.05 to 1 wt. %, for example, from 0.1 to 1 wt. %, or from 0.3 to 1 wt. %, or from 0.5 to 1 wt. %, based on the total weight of the catalyst. Embodiment 45. The catalyst of embodiment 38, wherein the palladium is present in the catalyst in an amount ranging from 0.05 to 0.8 wt.%, for example, from 0.1 to 0.8 wt.%, or from 0.3 to 0.8 wt.%, or from 0.5 to 0.8 wt.%, based on the total weight of the catalyst. Embodiment 46. The catalyst of any one of embodiments 1 to 45, wherein gold is present in the catalyst. Embodiment 47. The catalyst of embodiment 46, wherein the gold is present in the catalyst in an amount ranging from 0.1 to 10 wt. %, for example, from 0.5 to 10 wt. %, or from 1 to 10 wt. %, or from 2 to 10 wt. %, or from 5 to 10 wt. %, based on the total weight of the catalyst. Embodiment 48. The catalyst of embodiment 46, wherein the gold is present in the catalyst in an amount ranging from 0.05 to 7 wt.%, for example, from 0.1 to 7 wt.%, or from 0.5 to 7 wt.%, or from 1 to 7 wt.%, or from 2 to 7 wt.%, based on the total weight of the catalyst. Embodiment 49. The catalyst of embodiment 46, wherein the gold is present in the catalyst in an amount ranging from 0.05 to 5 wt.%, for example, from 0.1 to 5 wt.%, or from 0.5 to 5 wt.%, or from 1 to 5 wt.%, or from 2 to 5 wt.%, based on the total weight of the catalyst. Embodiment 50. The catalyst of embodiment 46, wherein the gold is present in the catalyst in an amount ranging from 0.05 to 2 wt.%, e.g., from 0.1 to 2 wt.%, or from 0.3 to 2 wt.%, or from 0.5 to 2 wt.%, or from 1 to 2 wt.%, based on the total weight of the catalyst. Embodiment 51. The catalyst of embodiment 46, wherein the gold is present in the catalyst in an amount ranging from 0.05 to 1.5 wt. %, e.g., from 0.1 to 1.5 wt. %, or from 0.3 to 1.5 wt. %, or from 0.5 to 1.5 wt. %, based on the total weight of the catalyst. Embodiment 52. The catalyst of embodiment 46, wherein the gold is present in the catalyst in an amount ranging from 0.05 to 1 wt. %, e.g., from 0.1 to 1 wt. %, or from 0.3 to 1 wt. %, or from 0.5 to 1 wt. %, based on the total weight of the catalyst. Embodiment 53. The catalyst of embodiment 46, wherein the gold is present in the catalyst in an amount ranging from 0.05 to 0.8 wt. %, for example, from 0.1 to 0.8 wt. %, or from 0.3 to 0.8 wt. %, or from 0.5 to 0.8 wt. %, based on the total weight of the catalyst. Embodiment 54. The catalyst of any one of embodiments 1 to 53, wherein manganese is present in the catalyst in an amount ranging from 0.5 to 15 wt. %, e.g., from 0.5 to 12 wt. %, or from 0.5 to 10 wt. %, based on the total weight of the catalyst. Embodiment 55. The catalyst of any one of embodiments 1 to 53, wherein manganese is present in the catalyst in an amount ranging from 1 to 20 wt. %, for example, from 1 to 15 wt. %, or from 1 to 12 wt. %, or from 1 to 10 wt. %, based on the total weight of the catalyst. Embodiment 56. The catalyst of any one of embodiments 1 to 53, wherein manganese is present in the catalyst in an amount ranging from 2 to 20 wt. %, for example, from 2 to 15 wt. %, or from 2 to 12 wt. %, or from 2 to 10 wt. %, based on the total weight of the catalyst. Embodiment 57. The catalyst of any one of embodiments 1 to 53, wherein manganese is present in the catalyst in an amount ranging from 4 to 20 wt. %, for example, from 4 to 15 wt. %, or from 4 to 12 wt. %, or from 4 to 10 wt. %, based on the total weight of the catalyst. Embodiment 58. The catalyst of any one of embodiments 1 to 57, wherein the weight ratio of platinum, palladium, and / or gold to manganese is at least 0.05:1, such as at least 0.1:1. Embodiment 59. The catalyst of any one of embodiments 1 to 58, wherein the weight ratio of platinum, palladium, and / or gold to manganese is at most 5:1, e.g., at most 2:1, or 1:1, or 0.5:1. Embodiment 60. The catalyst of any one of embodiments 1 to 59, wherein the ratio of platinum, palladium, and / or gold to manganese is in the range of 0.05:1 to 1:1 (e.g., in the range of 0.05:1 to 2:1, or 0.05:1 to 1:1, or 0.05:1 to 0.5:1, or 0.05:1 to 0.3:1, or 0.07:1 to 5:1, or 0.07:1 to 2:1, or 0.07:1 to 1:1, or 0.07:1 to 0.5:1, or 0.07:1 to 0.3:1, or 0.1:1 to 5:1, or 0.1:1 to 2:1, or 0.1:1 to 1:1, or 0.1:1 to 0.5:1, or 0.1:1 to 0.3:1). Embodiment 61. The catalyst of any one of embodiments 1 to 60, wherein the total amount of cerium, titanium, aluminum, zirconium, manganese, platinum, palladium, and gold in the catalyst is at least 90% by weight, e.g., at least 95% by weight, or at least 98% by weight, of the catalyst, on a metals basis. Embodiment 62. The catalyst of any one of embodiments 1 to 61, wherein the catalyst has an additional metal content (i.e., not Mn, Pd, Pt, Au, Ce, Ti, Al, or Zr) of 10 wt. % or less (e.g., 5 wt. % or less, or 2 wt. % or less, or 1 wt. % or less) based on the total weight of the catalyst. Embodiment 63. The catalyst of any one of embodiments 1 to 62, wherein the catalyst has a Cu content of 10 wt. % or less (e.g., 5 wt. % or less, or 2 wt. % or less, or 1 wt. % or less), based on the total weight of the catalyst. Embodiment 64. The catalyst of any one of embodiments 1 to 63, wherein the catalyst has an alkali metal content of 10 wt. % or less (e.g., 5 wt. % or less, or 2 wt. % or less, or 1 wt. % or less), based on the total weight of the catalyst. Embodiment 65. The catalyst of any one of embodiments 1 to 64, wherein the catalyst has an alkaline earth metal content of 10 wt. % or less (e.g., 5 wt. % or less, or 2 wt. % or less, or 1 wt. % or less), based on the total weight of the catalyst. Embodiment 66. A method for making the catalyst of any one of Embodiments 1 to 65, comprising: providing a support which is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support comprising a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; contacting the support with one or more liquids each comprising one or more platinum, palladium, or gold-containing compounds and / or one or more manganese-containing compounds dispersed in a solvent; evaporating the solvent to form a catalyst precursor; calcining said catalyst precursor. Embodiment 67. The method of embodiment 66, wherein contacting the support with a liquid comprises adding a volume of liquid equal to the pore volume of the support. Embodiment 68 The method of embodiment 66, wherein contacting the support with a liquid comprises adding the liquid in an amount greater than the pore volume of the support. Embodiment 69. The method of any one of embodiments 66 to 68, wherein the ratio of the amount of liquid to the amount of carrier by mass is in the range of 1:1 to 5:1 (e.g., in the range of 1:1 to 3:1). Embodiment 70. The method of any one of embodiments 66 to 69, wherein the slurry is obtained by contacting the carrier with a liquid. Embodiment 71 The method of any one of embodiments 66 to 70, wherein evaporating the solvent occurs at ambient temperature. Embodiment 72. The method of any one of embodiments 66 to 70, wherein evaporating the solvent is carried out at an elevated temperature (e.g., in the range of 50 to 150°C) for a drying time (e.g., 24 hours). Embodiment 73. The method of any one of embodiments 66 to 70, wherein evaporating the solvent is carried out under vacuum and at elevated temperature (e.g., in the range of 50 to 150°C) for a drying time (e.g., 24 hours). Embodiment 74. The method of any one of embodiments 66 to 70, wherein evaporating the solvent is carried out at elevated temperature (e.g., in the range of 30 to 100°C) in a stirred dry bath. Embodiment 75. The method of any one of embodiments 66-74, wherein calcining the catalyst precursor is carried out for a calcination time ranging from 0.5 to 24 hours (e.g., from 0.5 to 15 hours, or from 0.5 to 10 hours, or from 0.5 to 5 hours). Embodiment 76 The method of any one of embodiments 66 to 75, wherein the step of calcining the catalyst precursor is carried out for calcination in the range of 100 to 600°C (e.g., in the range of 120 to 500°C). Embodiment 77. The catalyst of any one of embodiments 1 to 65, made by the method of any one of embodiments 66 to 76. Embodiment 78. A method for performing a reverse water gas shift reaction, comprising: 78. A process comprising contacting the catalyst of any one of embodiments 1 to 65 and 77 with a feed stream comprising CO and H at a temperature in the range of 200 to 900 °C to form a product stream comprising CO and H, wherein the product stream has a lower concentration of CO and a higher concentration of CO than the feed stream. Embodiment 79. The method of embodiment 78, wherein the reverse water gas shift reaction has a CO selectivity of at least 95%, such as at least 96%. Embodiment 80 The method of embodiment 78, wherein the reverse water gas shift reaction has a CO selectivity of at least 98%, e.g., at least 99%. Embodiment 81. The method of any one of embodiments 78-80, wherein the reverse water gas shift reaction has a methane selectivity of 5% or less, such as 4% or less. Embodiment 82 The method of any one of embodiments 78-80, wherein the reverse water gas shift reaction has a methane selectivity of 2% or less, such as 1% or less. Embodiment 83 The method of any one of embodiments 78-80, wherein the reverse water gas shift reaction has a methane selectivity of 0.5% or less, such as 0.2% or less. Embodiment 84 The method of any of embodiments 78-83, having a CO2 conversion of at least 5%, such as at least 10%, or 20%. Embodiment 85. The method of any one of embodiments 78-83, having a CO2 conversion of at least 30%, for example, at least 40%. Embodiment 86. The method of any one of embodiments 78-85, having a CO2 conversion of 90% or less, e.g., 80% or less or 70% or less. Embodiment 87. The method of any one of embodiments 78-85, having a CO2 conversion of 65% or less, e.g., 60% or less. Embodiment 88a. The method of any one of embodiments 78 to 87, carried out at a temperature in the range of 200 to 850°C, e.g., 200 to 800°C, or 200 to 750°C, or 200 to 700°C, or 200 to 650°C, or 200 to 600°C. Embodiment 88b. The method of any one of embodiments 78 to 87, carried out at a temperature in the range of 250 to 900°C, e.g., 250 to 850°C, or 250 to 800°C, or 250 to 700°C, or 250 to 650°C, or 250 to 600°C. Embodiment 89. The method of any one of embodiments 78 to 87, carried out at a temperature in the range of 300 to 900°C, e.g., 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. Embodiment 90. The method of any one of embodiments 78 to 87, carried out at a temperature in the range of 350 to 900°C, e.g., 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. Embodiment 91. The method of any one of embodiments 78 to 87, carried out at a temperature in the range of 400 to 900°C, e.g., 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. Embodiment 92. The method of any one of embodiments 78 to 87, carried out at a temperature in the range of 450 to 900°C, e.g., 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. Embodiment 93. The method of any one of embodiments 78 to 87, carried out at a temperature in the range of 500 to 900°C, e.g., 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. Embodiment 94. The method of any one of embodiments 78 to 87, carried out at a temperature in the range of 550 to 900°C, e.g., 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. Embodiment 95 The method of any of embodiments 78-94, wherein at least a portion of the H2 in the feed stream is from a renewable source. Embodiment 96. The method of any one of embodiments 78-95, wherein at least a portion of the H2 in the feed stream is green hydrogen. Embodiment 97. The method of any one of embodiments 78-96, wherein at least a portion of the H2 in the feed stream is blue hydrogen. Embodiment 98. The method of any of embodiments 78-97, wherein at least a portion of the H2 in the feed stream is gray hydrogen, black hydrogen, brown hydrogen, pink hydrogen, turquoise hydrogen, yellow hydrogen, and / or white hydrogen. Embodiment 99. The method of any one of embodiments 78-98, wherein at least a portion of the CO2 in the feed stream is from a renewable resource. Embodiment 100. The method of any of embodiments 78-99, wherein at least a portion of the CO2 of the feed stream is from direct air capture. Embodiment 101. The method of any of embodiments 78-100, wherein at least a portion of the CO2 of the feed stream is captured from a manufacturing plant, such as a bioethanol plant, a steel mill, or a cement plant. Embodiment 102. The method of any of embodiments 78-101, wherein the molar ratio of H2 to CO2 in the feed stream is at least 0.1:1, such as at least 0.5:1. Embodiment 103. The method of any of embodiments 78-101, wherein the molar ratio of H2 to CO2 in the feed stream is at least 0.9:1, e.g., at least 1:1 or at least 1.5:1. Embodiment 104. The method of any of embodiments 78-101, wherein the molar ratio of H2 to CO2 in the feed stream is at least 2:1, such as at least 2.5:1. Embodiment 105. The method of any of embodiments 78-104, wherein the molar ratio of H2 to CO2 in the feed stream is 100:1 or less, e.g., 75:1 or less, or 50:1 or less. Embodiment 106. The method of any of embodiments 78-104, wherein the molar ratio of H2 to CO2 in the feed stream is 20:1 or less, e.g., 15:1 or less, or 10:1 or less. Embodiment 107. The method of any one of embodiments 78 to 104, wherein the molar ratio of H2 to CO2 in the feed stream ranges from 0.5:1 to 10:1. Embodiment 108. The method of any of embodiments 78 to 107, carried out at a pressure in the range of 1 to 100 barg (e.g., 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, or 10 to 50 barg, or 10 to 40 barg, or 10 to 35 barg, or 20 to 70 barg, or 20 to 50 barg, or 20 to 40 barg, or 20 to 35 barg, or 25 to 70 barg, or 25 to 50 barg, or 25 to 40 barg, or 25 to 35 barg). Embodiment 109. The method of any one of embodiments 78 to 108, carried out at a GHSV in the range of 1,000 to 2,000,000 h-1 (e.g., 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). Embodiment 110. The method of any one of embodiments 78-109, wherein the product stream comprises 95 mol% or less CO2 (e.g., 90 mol% or less CO2). Embodiment 111. The method of any one of embodiments 78-109, wherein the product stream comprises 85 mol% or less CO2 (e.g., 80 mol% or less CO2). Embodiment 112. The method of any one of embodiments 78-109, wherein the product stream comprises 75 mol% or less CO2 (e.g., 70 mol% or less CO2). Embodiment 113. The method of any of embodiments 78-112, wherein the product stream further comprises CO2, and the method further comprises recycling at least a portion of the CO2 of the product stream to the feed stream. Embodiment 114 The method of any of embodiments 78-113, wherein the product stream further comprises hydrogen, and the method further comprises recycling at least a portion of the hydrogen of the product stream to the feed stream. Embodiment 115. The method of any one of embodiments 78 to 114, wherein the ratio of H2:CO in the 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). Embodiment 116 The method of any one of embodiments 78 to 115, wherein the product stream comprises 20 mol% or less methane, such as 15 mol% or less methane. Embodiment 117. The method of any of embodiments 78-115, wherein the product stream comprises 10 mol% or less methane, e.g., 5 mol% or less, or 1 mol% or less, or 0.5 mol% or less, or 0.1 mol% or less methane. Embodiment 118 The method of any one of embodiments 78 to 117, comprising activating the catalyst before contacting the catalyst with the feed stream. Embodiment 119. The method of embodiment 118, wherein activating the catalyst comprises contacting the catalyst with a reducing stream comprising a reducing gas (e.g., hydrogen). Embodiment 120. The method of embodiment 118 or embodiment 119, wherein the reducing stream comprises hydrogen in an amount of at least 25 mol % (e.g., at least 50 mol %, or 75 mol %, or 90 mol %). Embodiment 121. The method of any one of embodiments 118 to 120, wherein activating the catalyst is carried out at a temperature in the range of 200 to 800°C (e.g., 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). Embodiment 122 The method of any of embodiments 118-121, wherein activating the catalyst provides a catalyst that is reduced by at least 10% (e.g., at least 25%, or 50%). Embodiment 123. A process for carrying out an integrated Fischer-Tropsch process, comprising: forming a first feed stream comprising H2 and CO2; contacting the 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 conduct a reverse water gas shift reaction and 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 H and at least a portion of the CO of said first product stream at a second temperature and a second pressure to form a second product stream comprising C5+ hydrocarbons; The reverse water gas shift catalyst is a supported reverse water gas shift catalyst, a support which is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support comprising a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; At least one of platinum, palladium, and gold present in an amount ranging from 0.05 to 10 weight percent of the catalyst, based on the total weight of the catalyst; and and manganese present in an amount ranging from 0.5 to 20 weight percent of said catalyst, based on the total weight of said catalyst. Embodiment 124. The process of embodiment 123, wherein the molar ratio of H2 to CO2 in the first feed stream is at least 0.1:1, such as at least 0.5:1. Embodiment 125. The process of embodiment 123, wherein 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. Embodiment 126. The process of embodiment 123, wherein the molar ratio of H2 to CO2 in the first feed stream is at least 2:1, e.g., at least 2.5:1. Embodiment 127. The process of any one of embodiments 1 to 126, wherein 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. Embodiment 128. The process of any one of embodiments 1 to 126, wherein 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. Embodiment 129. The process of any one of embodiments 1 to 128, wherein the molar ratio of H2 to CO2 in the first feed stream is in the range of 0.5:1 to 10:1. Embodiment 130 The process of any one of embodiments 1 to 129, wherein the first feed stream further comprises CO. Embodiment 131. The process of any one of embodiments 1 to 130, wherein the first feed stream further comprises one or more inert gases (e.g., nitrogen and / or methane). Embodiment 132. The process of any one of embodiments 1 to 131, wherein the reverse water gas shift reaction has a CO selectivity of at least 70%, such as at least 80%. Embodiment 133 The process of any one of embodiments 1 to 131, wherein the reverse water gas shift reaction has a CO selectivity of at least 85%, for example, or at least 90%. Embodiment 134. The process of any one of embodiments 1 to 133, wherein the reverse water gas shift reaction has a CO selectivity of at least 95%, such as at least 96%. Embodiment 135. The process of any one of embodiments 1 to 133, wherein the reverse water gas shift reaction has a CO selectivity of at least 98%, for example, or at least 99%. Embodiment 136. The process of any one of embodiments 1 to 135, wherein the reverse water gas shift reaction has a methane selectivity of 5% or less, such as 4% or less. Embodiment 137. The process of any one of embodiments 1 to 135, wherein the reverse water gas shift reaction has a methane selectivity of 2% or less, such as 1% or less. Embodiment 138. The process of any one of embodiments 1 to 135, wherein the reverse water gas shift reaction has a methane selectivity of 0.5% or less, such as 0.2% or less. Embodiment 139. The process of any one of embodiments 1 to 138, wherein the reverse water gas shift reaction has a CO2 conversion of at least 5%, such as at least 10%, or 20%. Embodiment 140. The process of any one of embodiments 1 to 138, wherein the reverse water gas shift reaction has a CO2 conversion of at least 30%, such as at least 40%. Embodiment 141. The process of any one of embodiments 1 to 140, wherein the reverse water gas shift reaction has a CO2 conversion of 90% or less, e.g., 80% or less or 70% or less. Embodiment 142. The process of any one of embodiments 1 to 140, wherein the reverse water gas shift reaction has a CO2 conversion of 65% or less, such as 60% or less. Embodiment 143. The process of any one of embodiments 1 to 142, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 200 to 850°C, e.g., 200 to 850°C, or 200 to 750°C, or 200 to 700°C, or 200 to 650°C, or 200 to 600°C. Embodiment 144. The process of any one of embodiments 1 to 142, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 250 to 900°C, e.g., 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. Embodiment 145. The process of any one of embodiments 1 to 142, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 300 to 900°C, e.g., 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. Embodiment 146. The process of any one of embodiments 1 to 142, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 350 to 900°C, e.g., 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. Embodiment 147. The process of any one of embodiments 1 to 142, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 400 to 900°C, e.g., 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. Embodiment 148. The process of any one of embodiments 1 to 142, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 450 to 900°C, e.g., 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. Embodiment 149. The process of any one of embodiments 1 to 142, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 500 to 900°C, e.g., 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. Embodiment 150. The process of any one of embodiments 1 to 142, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 550 to 900°C, e.g., 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. Embodiment 151. The process of any one of embodiments 1 to 142, wherein the reverse water gas shift reaction is carried out at a temperature in the range of 200 to 500°C, e.g., 200 to 450°C, or 200 to 400°C, or 200 to 350°C, or 250 to 500°C, e.g., 250 to 450°C, or 250 to 400°C, or 250 to 350°C. Embodiment 152. The process of any of embodiments 1-151, wherein the reverse water gas shift reaction is carried out at a pressure in the range of 1 to 100 barg (e.g., 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, or 10 to 50 barg, or 10 to 40 barg, or 10 to 35 barg, or 20 to 70 barg, or 20 to 50 barg, or 20 to 40 barg, or 20 to 35 barg, or 25 to 70 barg, or 25 to 50 barg, or 25 to 40 barg, or 25 to 35 barg). Embodiment 153. The process of any of embodiments 1-152, 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 (e.g., 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). Embodiment 154. The process of any one of embodiments 1 to 153, wherein the process comprises activating the reverse water gas shift catalyst, for example, before contacting the reverse water gas shift catalyst with the first feed stream. Embodiment 155. The process of embodiment 154, wherein activating the rWGS catalyst comprises contacting the rWGS catalyst with a reducing stream comprising a reducing gas (e.g., hydrogen). Embodiment 156. The process of embodiment 154 or embodiment 155, wherein the reducing stream comprises hydrogen in an amount of at least 25 mol % (e.g., at least 50 mol %, or 75 mol %, or 90 mol %). Embodiment 157. The process of any of embodiments 154 to 156, wherein the activation of the rWGS catalyst is carried out at a temperature in the range of 200°C to 800°C (e.g., 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). Embodiment 158 The process of any of embodiments 154-157, wherein activating the rWGS catalyst results in at least 10% (e.g., at least 25%, or 50%) reduced catalyst. Embodiment 159. The process of any one of embodiments 1 to 158, wherein the first product stream comprises 95 mol% or less CO2 (e.g., 90 mol% or less CO2). Embodiment 160. The process of any one of embodiments 1-158, wherein the first product stream comprises 85 mol% or less CO2 (e.g., 80 mol% or less CO2). Embodiment 161. The process of any one of embodiments 1 to 158, wherein the first product stream comprises 75 mol % or less CO2 (e.g., 70 mol % or less CO2). Embodiment 162. The process of any of embodiments 1-158, wherein the first product stream comprises CO2 in the range of 5-95 mol%, e.g., 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% CO2. Embodiment 163. The process of any one of embodiments 1 to 162, wherein the first product stream comprises 20 mol % or less methane, such as 15 mol % or less methane. Embodiment 164. The process of any of embodiments 1-162, wherein the first product stream comprises 10 mol% or less methane, e.g., 5 mol% or less, or 1 mol% or less, or 0.5 mol% or less, or 0.1 mol% or less methane. Embodiment 165. The process of any one of embodiments 1 to 164, wherein the ratio of H2:CO in the first product stream is up to 100:1, e.g., up to 50:1, or up to 25:1, or up to 10:1. Embodiment 166. The process of any one of embodiments 1 to 164, wherein the ratio of H2:CO 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). Embodiment 167. The process of any one of embodiments 1-166, wherein the process further comprises separating the first product stream to recycle at least a portion of one or more components of the first product stream to the first feed stream. Embodiment 168. The process of any of embodiments 1-167, wherein the process further comprises separating the first product stream to recycle 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 of the first product stream to the first feed stream. Embodiment 169. The process of any of embodiments 1-168, further comprising separating the first product stream to recycle at least a portion of the H2 (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%) to the first feed stream. Embodiment 170. The process of any one of embodiments 1 to 169, wherein the process further comprises separating at least a portion of the H2 and / or CO from the first product stream and contacting it with a Fischer-Tropsch catalyst to activate the Fischer-Tropsch catalyst. Embodiment 171. The process of any one of embodiments 1 to 170, wherein the process further comprises 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. Embodiment 172. The process of any one of embodiments 1 to 171, wherein the first product stream comprises one or more light hydrocarbons (e.g., methane, ethane, propane). Embodiment 173. The process of embodiment 172, further comprising separating at least a portion of the one or more light hydrocarbons from the first product stream to provide a light hydrocarbon stream. Embodiment 174. The process of any one of embodiments 1 to 173, wherein the process further comprises 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. Embodiment 175. The process of any one of embodiments 1-174, wherein the process further comprises exchanging heat between at least a portion of the first product stream and the steam generation zone, thereby cooling at least a portion of the first product stream and providing heat to the steam generation zone. Embodiment 176. The process of embodiment 175, further comprising generating steam from the heat provided to the steam generation zone and generating electricity from the steam. Embodiment 177. The process of embodiment 175 or 176, wherein steam is used to heat the first feed stream and / or the second feed stream. Embodiment 178. The process of any of embodiments 1-177, wherein at least 25% of the CO of the first product stream is contained in the second feed stream, e.g., at least 50% of the CO, at least 75% of the CO, or at least 90% of the CO of the first product stream. Embodiment 179. The process of any one of embodiments 1 to 178, wherein CO is provided to the second feed stream from a CO source other than the first product stream. Embodiment 180. The process of any one of embodiments 1-179, wherein the first product stream comprises H2 and the second feed stream comprises at least a portion of the H2 of the first product stream. Embodiment 181. The process of any of embodiments 1-180, wherein at least 25% of the H2 of the first product stream, e.g., at least 50% of the H2, at least 75% of the H2, or at least 90% of the H2 of the first product stream, is contained in the second feed stream. Embodiment 182. The process of any one of embodiments 1 to 181, wherein the second feed stream is provided with H2 from a hydrogen source other than the first product stream. Embodiment 183. The process of any one of embodiments 1 to 182, wherein the second feed stream comprises at least a portion of the CO2 of the first product stream. Embodiment 184. The process of any of embodiments 1-183, wherein at least 10% of the CO2 of the first product stream, e.g., at least 25% of the CO2, at least 50% of the CO2, at least 75% of the CO2, or at least 90% of the CO2 of the first product stream, is contained in the second feed stream. Embodiment 185. The process of any one of embodiments 1 to 183, wherein the second feed stream does not contain a substantial amount of the CO2 of the first product stream. Embodiment 186. The process of any one of embodiments 1 to 185, wherein the 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, e.g., in the range of 1:1 to 3:1. Embodiment 187. The process of any of embodiments 1-186, wherein the portion of the first product stream included in the second feed stream has a water content of 10 mol% or less, e.g., or 2 mol% or less, or 0.5 mol% or less. Embodiment 188. The process of any of embodiments 1-187, wherein the portion of the first product stream included in the second feed stream has a CO2 content in the range of 10 to 95 mol% CO2, e.g., 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. Embodiment 189. The process of any one of embodiments 1 to 188, wherein the second feed stream has an H2:CO ratio in the range of 0.5:1 to 6:1. Embodiment 190. The process of any one of embodiments 1 to 188, 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. Embodiment 191. The process of any of embodiments 1-188, wherein the second feed stream has an H2:CO ratio of at least 1.4:1, e.g., in the range of 1.4:1 to 3:1, or 1.4:1 to 2.5:1. Embodiment 192. The process of any of embodiments 1-191, wherein the second feed stream comprises up to 80%, e.g., 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% of one or more inerts. Embodiment 193. The process of any of embodiments 1-191, wherein the second feed stream comprises up to 80%, e.g., 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% of one or more inerts selected from CO2, methane, and nitrogen. Embodiment 194. The process of any of embodiments 1-193, wherein the second feed stream comprises up to 80% CO2, e.g., 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%. Embodiment 195. The process of any one of embodiments 1 to 194, wherein 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. Embodiment 196. The process of any one of embodiments 1 to 195, wherein the Fischer-Tropsch catalyst comprises cobalt, iron, rhodium, ruthenium, or a combination thereof. Embodiment 197. The process of any one of embodiments 1 to 195, wherein the Fischer-Tropsch catalyst comprises cobalt, e.g., calculated as Co(0), in an amount ranging from 5-25 wt%, e.g., 7-25 wt%, or 10-25 wt%, or 5-20 wt%, or 7-20 wt%, or 10-20 wt%. Embodiment 198. The process of any of embodiments 1 to 195, wherein the Fischer-Tropsch catalyst comprises iron, e.g., calculated as Fe(0), in an amount ranging from 5-95 wt%, e.g., 10-95 wt%, or 25-95 wt%, or 50-95 wt%, or 5-85 wt%, or 10-85 wt%, or 25-85 wt%, or 50-85 wt%, or 5-75 wt%, or 10-75 wt%, or 25-75 wt%. Embodiment 199. The process of any one of embodiments 196 to 198, wherein the Fischer-Tropsch catalyst further comprises manganese. Embodiment 200. The process of embodiment 199, wherein manganese is present in an amount in the range of up to 15 wt.%, for example up to 12 wt.%, or up to 10 wt.%, or up to 7 wt.%, or from 0.1 to 15 wt.%, for example, from 0.1 to 10 wt.%, or from 0.1 to 5 wt.%, 0.5 to 15 wt.%, or from 0.5 to 10 wt.%, or from 0.5 to 5 wt.%, calculated as Mn(0). Embodiment 201. The process of any one of embodiments 1 to 200, wherein the Fischer-Tropsch catalyst is a supported catalyst, and the support comprises at least one of titanium oxide, zirconium oxide, cerium oxide, aluminum oxide, silicon oxide, and zinc oxide. Embodiment 202. The process of any one of embodiments 1 to 200, wherein the Fischer-Tropsch catalyst is a supported catalyst, and the support comprises at least one of titanium oxide, aluminum oxide, and silicon oxide. Embodiment 203. The process of any one of embodiments 1 to 200, wherein the Fischer-Tropsch catalyst is a supported catalyst and the support is a titanium dioxide support. Embodiment 204. The process of any one of embodiments 1 to 203, wherein the Fischer-Tropsch catalyst is activated by contact with a reducing gas, such as hydrogen. Embodiment 205. The process of embodiment 204, wherein the reducing gas comprises at least a portion of the hydrogen from the first product stream. Embodiment 206 The process of any one of embodiments 1 to 203, wherein the Fischer-Tropsch catalyst is activated by contact with H2 and CO. Embodiment 207. The process of embodiment 206, wherein the reducing gas comprises at least a portion of the H2 and CO from the first product stream. Embodiment 208 The process of any one of embodiments 204 to 206, wherein the activation is carried out at a temperature in the range of 200 to 400°C. Embodiment 209. The process of any one of embodiments 1 to 208, wherein the second temperature is in the range of 150 to 400°C (e.g., 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). Embodiment 210. The process of any one of embodiments 1 to 209, wherein the second temperature is in the range of 200 to 350°C. Embodiment 211. The method of any one of embodiments 1-210, wherein the first temperature is within 100°C of the second temperature, e.g., within 50°C of the second temperature, or within 25°C of the second temperature. Embodiment 212. The process of any one of embodiments 1 to 210, wherein the first temperature is at least 100°C higher than the second temperature, e.g., at least 150°C higher than the second temperature, or at least 200°C higher than the second temperature. Embodiment 213. The process of any one of embodiments 1 to 212, wherein the second pressure is in the range of 10-50 barg (e.g., 20-50 barg, or 25-50 barg, or 10-40 barg, or 20-40 barg, or 25-40 barg, or 10-35 barg, or 20-35 barg, or 25-35 barg). Embodiment 214. The process of any one of embodiments 1 to 213, wherein the second pressure is in the range of 20-50 barg. Embodiment 215. The process of any one of embodiments 1 to 214, wherein the Fischer-Tropsch reaction is carried out at a GHSV in the range of from 1,000 to 2,000,000 h-1 (e.g., in the range of from 1,000 to 1,200,000 h-1, or from 1,000 to 500,000 h-1, or from 1,000 to 100,000 h-1, or from 5,000 to 1,200,000 h-1, or from 5,000 to 500,000 h-1, or from 5,000 to 100,000 h-1, or from 10,000 to 1,200,000 h-1, or from 10,000 to 500,000 h-1, or from 10,000 to 100,000 h-1). Embodiment 216. The process of any one of embodiments 1 to 215, wherein contacting the Fischer-Tropsch catalyst with the second feed stream to provide the second product stream is conducted at a C5+ selectivity of at least 30%, e.g., at least 50%, or at least 70%. Embodiment 217. The process of any one of embodiments 1 to 216, wherein contacting the Fischer-Tropsch catalyst with the second feed stream to provide the second product stream is carried out at a selectivity for C5+ alkanes of at least 30%, e.g., at least 50%, or at least 70%. Embodiment 218. The process of any one of embodiments 1 to 217, wherein contacting the Fischer-Tropsch catalyst with the second feed stream to provide the second product stream is carried out at a selectivity to C5+ alkanes and C5+ alcohols of at least 30%, e.g., at least 50%, or at least 70%. Embodiment 219. The process of any one of embodiments 1 to 218, further comprising separating at least a portion of the water from the second product stream. Embodiment 220. The process of any one of embodiments 1 to 219, further comprising separating at least a portion of the C1-C4 hydrocarbons from the second product stream to provide a light hydrocarbon stream. Embodiment 221. The process of embodiment 220, further comprising including at least a portion of the light hydrocarbon stream in the first feed stream and / or the second feed stream. Embodiment 222. The process of embodiment 220 or embodiment 221, further comprising oxidizing at least a portion of the light hydrocarbon stream to provide a CO and / or CO2-containing pOX stream, and including at least a portion of the pOX stream in the first feed stream and / or the second stream. Embodiment 223. The process of any of embodiments 220-222, further comprising 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 reformate stream, and including at least a portion of the reformate stream in the first feed stream and / or the second feed stream. Embodiment 224 The process of embodiment 222 or embodiment 223, wherein the oxidation or reforming provides energy, thermal energy, or electrical energy. Embodiment 225 The process of any of embodiments 220-224, further comprising combusting at least a portion of the light hydrocarbon stream to provide energy, e.g., thermal energy or electrical energy. Embodiment 226. The process of embodiment 225, wherein thermal energy is provided and the thermal energy is used to heat the first feed stream. Embodiment 227. The process of any one of embodiments 1-226, wherein the process further comprises exchanging heat between at least a portion of the second product stream and the steam generation zone, thereby cooling at least a portion of the first feed stream and providing heat to the steam generation zone. Embodiment 228. The process of embodiment 227, further comprising generating steam from the heat provided to the steam generation zone and generating electricity from the steam. Embodiment 229. The process of embodiment 227 or 228, wherein steam is used to heat the first feed stream and / or the second feed stream. Embodiment 230. The process of any one of embodiments 1-229, wherein the process further comprises 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. Embodiment 231. The process of any one of embodiments 1 to 230, further comprising recycling at least a portion of the H2 of the second product stream to the second feed stream. Embodiment 232. The process of any one of embodiments 1 to 231, further comprising recycling at least a portion of the H2 of the second product stream to the first feed stream. Embodiment 233. The process of embodiment 232, further comprising providing H2 to the second feed stream from an H2 source other than the first product stream. Embodiment 234. The process of embodiment 233, wherein the H2 from the second product stream constitutes a majority of the H2 of the first feed stream, e.g., at least 90%, at least 95%, or at least 98% of the H2 of the first feed stream. Embodiment 235. The process of any one of embodiments 1 to 234, further comprising recycling at least a portion of the CO of the second product stream to the second feed stream. Embodiment 236. The process of any one of embodiments 1 to 235, further comprising recycling at least a portion of the CO of the second product stream to the first feed stream. Embodiment 237. The process of any one of embodiments 1 to 236, further comprising recycling at least a portion of the inerts of the second product stream to the second feed stream. Embodiment 238. The process of any one of embodiments 1 to 237, further comprising recycling at least a portion of the inerts of the second product stream to the first feed stream. Embodiment 239. The process of any one of embodiments 1 to 238, further comprising recycling at least a portion of the CO2 of the second product stream to the first feed stream. Embodiment 240. The process of embodiment 239, further comprising providing CO2 to the second feed stream from a CO2 source other than the first product stream. Embodiment 241. The process of embodiment 240, wherein the CO2 from the second product stream constitutes a majority of the CO2 of the first feed stream, e.g., at least 90%, at least 95%, or at least 98% of the CO2 of the first product stream. Embodiment 242. The process of any one of embodiments 1 to 241, wherein the one or more products are provided from at least a portion of the C5+ hydrocarbons of the second product stream. Embodiment 243. The process of embodiment 242, wherein the one or more products include fuels (e.g., gasoline, diesel fuel, aviation fuel), lubricants, and waxes. Embodiment 244. The process of any one of embodiments 1 to 243, further comprising hydrotreating at least a portion of the C5+ hydrocarbons of the second product stream. Embodiment 245. The process of any one of embodiments 1 to 244, wherein at least a portion of the CO2 of the first feed stream and / or the second feed stream is from a renewable resource. Embodiment 246. The process of any one of embodiments 1 to 245, wherein at least a portion of the CO2 of the first feed stream and / or the second feed stream is from direct air capture. Embodiment 247. The process of any of embodiments 1 to 246, wherein at least a portion of the CO2 of 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. Embodiment 248. The process of any one of embodiments 1 to 247, wherein at least a portion of the H2 of the first feed stream or the second feed stream is from a renewable source. Embodiment 249. The process of any one of embodiments 1 to 248, wherein at least a portion of the hydrogen in the first feed stream or the second feed stream is green hydrogen. Embodiment 250. The process of any one of embodiments 1 to 249, wherein at least a portion of the hydrogen in the first feed stream or the second feed stream is blue hydrogen. Embodiment 251. The process of any of embodiments 1 to 250, wherein at least a portion of the hydrogen in the first feed stream or the second feed stream is gray hydrogen, black hydrogen, brown hydrogen, pink hydrogen, turquoise hydrogen, yellow hydrogen, and / or white hydrogen. Embodiment 252. The process of any one of embodiments 1 to 251, further comprising providing at least a portion of the H2 to the first feed stream and / or the second feed stream by electrolysis of water. Embodiment 253. The process of embodiment 252, wherein the electrolysis of water is carried out at least in part using electricity from a renewable resource. Embodiment 254. The process of embodiment 252 or embodiment 253, wherein the electrolysis of water is carried out at least in part using electricity generated by heat exchange from the first product stream and / or the second product stream, or from steam produced by burning a light hydrocarbon stream. Embodiment 255. The process of any one of embodiments 252-254, further comprising providing at least a portion of the O2 produced in the electrolysis to the partial oxidation. Embodiment 256. The process of any one of embodiments 1 to 255, wherein the process is carried out in a reactor system comprising a first reactor disposed with a reverse water gas shift catalyst and a second reactor disposed with a Fischer-Tropsch catalyst. Embodiment 257. The process of any one of embodiments 1 to 255, wherein the process is carried out in a reactor system comprising a first catalyst bed disposed with a reverse water gas shift catalyst, and the second reaction zone comprises a second catalyst bed disposed with a Fischer-Tropsch catalyst. Embodiment 258 The process of embodiment 257, wherein the first reactor bed and the second reactor bed are located within the same reactor. Embodiment 259. The process of any one of embodiments 1 to 255, wherein the process is carried out in a reactor system comprising one or more first catalyst vessels in which a reverse water gas shift catalyst is disposed, and the second reaction zone comprises one or more second catalyst vessels in which a Fischer-Tropsch catalyst is disposed. Embodiment 260. The process of embodiment 259, wherein the one or more first catalyst vessels and the one or more second catalyst vessels are located within the same reactor. Embodiment 261. The process of any one of embodiments 1 to 260, wherein the process is carried out in a reactor system comprising a reactor in which the reverse water gas shift catalyst and the Fischer-Tropsch catalyst are disposed, e.g., in admixture.

[0177] The details set forth herein are presented by way of example only for purposes of illustrative discussion of preferred embodiments of the present invention and to provide what is believed to be the most useful and readily understood explanation of the principles and conceptual aspects of various embodiments of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than necessary for a fundamental understanding of the invention; the description, taken together with the figures and / or examples, will make clear to those skilled in the art how several forms of the present invention may be embodied in practice. Therefore, before the disclosed processes and devices are described, it should be understood that the aspects described herein are not limited to specific embodiments, apparatus, or configurations, which may, of course, vary. It should also be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting unless specifically defined herein.

[0178] As used in the context of describing the present invention (particularly in the context of the claims that follow), the terms "a," "an," "the," and similar referents should be construed to encompass both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The recitation of ranges of values herein is intended merely to serve as a shorthand process for individually referring to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated herein as if set forth individually 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.

[0179] All processes described herein can be performed in any suitable order of steps unless otherwise indicated herein or clearly contradicted by context. Any and all examples provided herein, or the use of exemplary language (e.g., "etc."), are intended merely to better clarify the invention and do not impose limitations on the scope of the invention as otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention. Unless the context clearly dictates otherwise, throughout this specification and the claims, words like "comprise," "comprising," and the like are to be construed in an inclusive sense, i.e., "including, but not limited to," rather than an exclusive or exhaustive sense. Words using the singular or plural also include the plural and singular, respectively. Furthermore, the words "herein," "above," and "below," and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application.

[0180] As will be understood by one of ordinary skill in the art, each embodiment disclosed herein can comprise, consist essentially of, or consist of its specified recited elements, steps, ingredients, or components. As used herein, the transitional phrases "comprise" or "comprises" mean including, but not limited to, and allow for the inclusion of unspecified elements, steps, ingredients, or components, even if they amount to a large amount. The transitional phrase "consisting of" excludes any unspecified element, step, ingredient, or component. The transitional phrase "consisting essentially of" limits the scope of the embodiment to the specified elements, steps, ingredients, or components, and those that do not materially affect the embodiment.

[0181] Unless indicated to the contrary, the numerical parameters set forth in the specification and attached 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 scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0182] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible, however, any numerical values inherently contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0183] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limiting. Each group member may be referred to and claimed individually or in any combination with other members of the group or other elements found herein. It is anticipated that one or more members of a group may be included in, or deleted from, a group for reasons of convenience and / or patentability. When any such inclusion or deletion occurs, the specification is deemed to include the group as modified and thus fulfill the written description of all Markush groups used in the appended claims.

[0184] Several embodiments of the present invention are described herein, including the best mode known to the inventors for carrying out the invention. Of course, variations on these described embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventors anticipate that skilled artisans will employ such variations as appropriate, and the inventors intend that the invention may be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or clearly contradicted by context.

[0185] Furthermore, it is to be understood that the embodiments of the invention disclosed herein are illustrative of the principles of the invention. Other modifications that may be employed are within the scope of the invention. Thus, by way of example, and not of limitation, alternative configurations of the invention may be utilized in accordance with the teachings herein. Accordingly, the invention is not limited to that precisely as shown and described.

Claims

1. 1. A method for conducting a reverse water gas shift reaction, comprising: contacting a supported reverse water gas shift catalyst with a feed stream comprising CO and H at a temperature in the range of 200 to 900°C to form a product stream comprising CO and H, wherein the product stream has a lower CO concentration and a higher CO concentration than the feed stream; The catalyst comprises a support which is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support comprising a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; at least one of platinum, palladium, and gold present in an amount ranging from 0.05 to 10 weight percent of the catalyst based on the total weight of the catalyst; and and manganese present in an amount ranging from 0.5 to 20 weight percent of said catalyst based on the total weight of said catalyst.

2. 10. The method of claim 1, wherein the reverse water gas shift reaction has a CO selectivity of at least 95%, such as at least 96%.

3. 2. The method of claim 1, wherein the reverse water gas shift reaction has a methane selectivity of 5% or less, such as at least 4%.

4. 10. The method of claim 1, having a CO2 conversion rate of at least 30%, such as at least 40%.

5. 10. The method of claim 1, having a CO2 conversion rate of 90% or less, for example, 80% or less or 70% or less.

6. 10. The method of claim 1, carried out at a temperature in the range of 550 to 800°C, such as 550 to 750°C, or 550 to 700°C, or 550 to 650°C, or 550 to 600°C.

7. 2. The process of claim 1, wherein the molar ratio of H2 to CO2 in the feed stream is in the range of 0.5:1 to 10:

1.

8. 10. The method of claim 1, wherein the product stream comprises 75 mol% or less CO2 (e.g., 70 mol% or less CO2).

9. 10. The method of claim 1, wherein the product stream further comprises CO2, and further comprising recycling at least a portion of the CO2 of the product stream to the feed stream.

10. 10. The method of claim 1, wherein the product stream further comprises hydrogen, and further comprising recycling at least a portion of the hydrogen of the product stream to the feed stream.

11. 10. The method of claim 1, wherein the product stream comprises no more than 20 mol% methane, such as no more than 15 mol% methane.

12. 10. The method of claim 1, wherein the product stream comprises no more than 10 mol% methane, e.g., no more than 5 mol%, or no more than 1 mol%, or no more than 0.5 mol%, or no more than 0.1 mol% methane.

13. 1. A method for conducting an integrated Fischer-Tropsch process, comprising: forming a first feed stream comprising H2 and CO2; contacting the first feed stream with a reverse water gas shift catalyst at a first temperature in the range of 200 to 900°C and a first pressure 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 H 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; the reverse water gas shift catalyst is a supported reverse water gas shift catalyst; a support which is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support comprising a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; at least one of platinum, palladium, and gold present in an amount ranging from 0.05 to 10% by weight of the catalyst based on the total weight of the catalyst; and and manganese present in an amount ranging from 0.5 to 20 weight percent of the catalyst based on the total weight of the catalyst.

14. 14. The method of claim 13, wherein the support comprises at least 70% by weight of the catalyst on an oxide basis.

15. 14. The method of claim 13, wherein the platinum is present in the catalyst in an amount ranging from 0.05 to 2 wt. %, based on the total weight of the catalyst.

16. 14. The method of claim 13, wherein the palladium is present in the catalyst in an amount ranging from 0.05 to 2 wt. % based on the total weight of the catalyst.

17. 14. The method of claim 13, wherein the gold is present in the catalyst in an amount ranging from 0.05 to 2 wt %, based on the total weight of the catalyst.

18. 14. The method of claim 13, wherein manganese is present in the catalyst in an amount ranging from 2 to 20 wt %, based on the total weight of the catalyst.

19. 14. The method of claim 13, wherein the ratio of platinum, palladium, and / or gold to manganese is in the range of 0.05:1 to 1:

1.

20. 14. The method of claim 13, wherein the molar ratio of H2 to CO2 in the first feed stream ranges from 0.5:1 to 10:

1.

21. 14. The method of claim 13, wherein the reverse water gas shift reaction has a methane selectivity of 2% or less.

22. 14. The method of claim 13, comprising activating the reverse water gas shift catalyst with a reducing stream comprising a reducing gas.

23. 14. The method of claim 13, wherein the first product stream comprises 75 mol % or less of CO2.

24. 14. The method of claim 13, wherein the first product stream comprises 5 mole percent or less of methane.

25. 14. The method of claim 13, wherein at least 25% of the CO of the first product stream is contained in the second feed stream.

26. 14. The method of claim 13, wherein the first product stream comprises H2 and at least 25% of the H2 of the first product stream is contained in the second feed stream.

27. 14. The method of claim 13, wherein at least 10% of the CO2 of the first product stream is contained in the second feed stream.

28. 14. The method of claim 13, wherein the second feed stream does not contain a substantial amount of the CO2 of the first product stream.

29. 14. The method of claim 13, wherein the second feed stream has a H2:CO ratio in the range of 0.5:1 to 6:

1.

30. 14. The method of claim 13, wherein the second temperature is in the range of 200 to 350°C.

31. 14. The method of claim 13, wherein the first temperature is at least 100° C. higher than the second temperature.

32. 14. The process of claim 13, wherein contacting the Fischer-Tropsch catalyst with the second feed stream to form the second product stream is conducted at a selectivity to C5+ alkanes of at least 30%.

33. 14. The method of claim 13, further comprising separating at least a portion of the C1 to C4 hydrocarbons from the second product stream to provide a light hydrocarbon stream.

34. 14. The method of claim 13, further comprising cooling at least a portion of the second product stream and heating at least a portion of the second feed stream by exchanging heat between at least a portion of the second product stream and at least a portion of the second feed stream.

35. 14. The method of claim 13, further comprising recycling at least a portion of the H2 of the second product stream to the second feed stream.

36. 14. The method of claim 13, further comprising recycling at least a portion of the H2 of the second product stream to the first feed stream, wherein the H2 from the second product stream comprises at least 90% of the H2 of the first feed stream.

37. 14. The method of claim 13, further comprising recycling at least a portion of the CO of the second product stream to the second feed stream or the first feed stream.

38. 14. The method of claim 13, further comprising recycling at least a portion of the CO2 of the second product stream to the first feed stream, wherein the CO2 from the second product stream comprises at least 90% of the CO2 of the first feed stream.

39. 1. A supported reverse water gas shift catalyst comprising: a support which is a cerium oxide support, a titanium oxide support, an aluminum oxide support, a zirconium oxide support, or a mixed oxide support comprising a mixture of two or more of cerium oxide, titanium oxide, aluminum oxide, and zirconium oxide; at least one of platinum, palladium, and gold present in an amount ranging from 0.05 to 10% by weight of the catalyst based on the total weight of the catalyst; and and manganese present in an amount ranging from 0.5 to 20 weight percent of said catalyst based on the total weight of said catalyst.

40. 40. The catalyst of claim 39, wherein at least a surface layer of the cerium oxide support comprises at least 90 wt. % cerium oxide, e.g., at least 95 wt. % cerium oxide, or at least 98 wt. % cerium oxide, on an oxide basis.

41. 40. The catalyst of claim 39, wherein the total amount of cerium, titanium, aluminum, zirconium, manganese, platinum, palladium, and gold in the catalyst is at least 90% by weight, e.g., at least 95% by weight, or at least 98% by weight, of the catalyst, on a metals basis.

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