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EP-4735169-A1 - NICKEL-GALLIUM CATALYSTS FOR REVERSE WATER-GAS SHIFT AND INTEGRATED FISCHER-TROPSCH PROCESSES

EP4735169A1EP 4735169 A1EP4735169 A1EP 4735169A1EP-4735169-A1

Abstract

The present disclosure relates generally to reverse water-gas shift processes, integrated Fischer-Tropsch processes, and a supported reverse water-gas shift catalyst for conducting these processes. The catalysts described herein include a support; nickel, present in an amount in the range of 0.05 to 20 wt%of the catalyst, based on the total weight of the catalyst; and gallium, present in an amount in the range of 0.5 to 20 wt%of the catalyst, based on the total weight of the catalyst.

Inventors

  • GUO, Meiling
  • Doskocil, Eric
  • PATERSON, ALEXANDER JAMES

Assignees

  • BP P.L.C.

Dates

Publication Date
20260506
Application Date
20230629

Claims (20)

  1. A supported reverse water-gas shift catalyst comprising: a support; nickel, present in an amount in the range of 0.05 to 20 wt%of the catalyst, based on the total weight of the catalyst; and gallium, present in an amount in the range of 0.5 to 20 wt%of the catalyst, based on the total weight of the catalyst.
  2. The catalyst of claim 1, wherein the support makes up at least 70 wt%of the catalyst, on an oxide basis.
  3. The catalyst of claim 1, wherein the support is a cerium oxide support.
  4. The catalyst of claim 3, wherein the cerium oxide support comprises at least 90 wt%cerium oxide, on an oxide basis.
  5. The catalyst of claim 1, wherein the support is a titanium oxide support.
  6. The catalyst of claim 5, wherein the titanium oxide support comprises at least 90 wt%titanium oxide, on an oxide basis.
  7. The catalyst of claim 1, wherein the support is an aluminum oxide support or a zirconium oxide support.
  8. The catalyst of claim 1, wherein nickel is present in the catalyst in an amount in the range of 0.1 to 10 wt%, based on the total weight of the catalyst.
  9. The catalyst of claim 1, wherein gallium is present in the catalyst in an amount in the range of 2 to 20 wt%, based on the total weight of the catalyst.
  10. The catalyst of claim 1, wherein a weight ratio of nickel to gallium is at least 0.05: 1.
  11. The catalyst of claim 1, wherein a weight ratio of nickel to gallium is at most 2: 1.
  12. The catalyst of claim 1, wherein a ratio of nickel to gallium is in the range of 0.05: 1 to 1: 1.
  13. The catalyst of claim 1, wherein the total amount of cerium, titanium, aluminum, zirconium, gallium, and nickel in the catalyst is at least 90 wt%, on a metallic basis.
  14. A method for making the catalyst of any of claims 1-13, the method comprising: providing a support; contacting the support with one or more liquids each comprising one or more nickel-containing compounds and/or one or more gallium-containing compounds dispersed in a solvent (s) ; allowing the solvent (s) to evaporate to provide a catalyst precursor; and calcining the catalyst precursor.
  15. A method for performing a reverse water-gas shift reaction, the method comprising: contacting at a temperature in the range of 250-900℃ a catalyst according to any of claims 1-13 with a feed stream comprising CO 2 and H 2 , to provide a product stream comprising CO and H 2 , the product stream having a lower concentration of CO 2 and a higher concentration of CO than the feed stream.
  16. A process for performing an integrated Fischer-Tropsch process, the process comprising: providing a first feed stream comprising H 2 and CO 2 ; contacting at a first temperature in the range of 250-900℃ and at a first pressure a reverse water-gas shift catalyst with the first feed stream to perform a reverse water-gas shift reaction to provide a first product stream comprising CO and H 2 , the first product stream having a lower concentration of CO 2 and a higher concentration of CO than the first feed stream; contacting at a second temperature and at a second pressure a Fischer-Tropsch catalyst with a second feed stream comprising H 2 and at least a portion of CO of the first product stream to provide a second product stream comprising C 5+ hydrocarbons, wherein the reverse water-gas shift catalyst is a supported reverse water-gas shift catalyst comprising: a support; nickel, present in an amount in the range of 0.05 to 20 wt%of the catalyst, based on the total weight of the catalyst; and gallium, present in an amount in the range of 0.5 to 20 wt%of the catalyst, based on the total weight of the catalyst.
  17. The process of claim 16, wherein the molar ratio of H 2 to CO 2 in the first feed stream is in the range of 0.5: 1 to 10: 1.
  18. The process of claim 16, wherein the reverse water-gas shift reaction has a CO selectivity of at least 50%.
  19. The process of claim 16, wherein the reverse water-gas shift reaction has a methane selectivity of no more than 40%.
  20. The process of claim 16, wherein the reverse water-gas shift reaction has a methane selectivity of no more than 10%.

Description

NICKEL-GALLIUM CATALYSTS FOR REVERSE WATER-GAS SHIFT AND INTEGRATED FISCHER-TROPSCH PROCESSES BACKGROUND OF THE DISCLOSURE 1. Field The present disclosure relates generally to reverse water-gas shift catalysts, processes of making the same, and processes for performing reverse water-gas shift reactions. The present disclosure also relates to integrating processes for performing reverse water-gas shift reactions with processes for performing Fischer-Tropsch reactions. 2. Technical Background The reverse water-gas shift reaction (rWGS) is an advantageous route to obtain carbon monoxide from carbon dioxide for further chemical processing. The rWGS converts carbon dioxide and hydrogen to carbon monoxide and water, as shown in Equation (1) . This can be used, for example, to modify the CO: H2 ratio of a gas mixture for further processing. The carbon monoxide and hydrogen so formed is a valuable feedstock for a number of chemical processes, for example, the well-known Fischer-Tropsch (FT) process, shown in Equation (2) . However, the rWGS reaction is not favored in all circumstances. For example, a competing reaction is the Sabatier reaction (Equation (3) ) , which decreases carbon monoxide yield in favor of methane production, which is not an active feedstock for FT. The strongly exothermic Sabatier reaction is thermodynamically favored over the endothermic rWGS reaction at lower reaction temperatures. As such, minimizing the methanation during rWGS, especially at low temperatures, can become a significant challenge. Similarly, the carbon monoxide product from rWGS can be hydrogenated to methane, as shown in Equation (4) . Hydrogenation of carbon monoxide to methane is also an exothermic reaction, so it too is favored at lower temperatures. The stoichiometry of the reaction requires at least a 3: 1 ratio  of hydrogen to carbon monoxide. This means that performing the rWGS reaction with a large excess of hydrogen to drive the equilibrium toward carbon monoxide (see Equation (1) ) is not always ideal because it runs the risk of hydrogenating the carbon monoxide product to form methane. Coupled with Equations (3) and (4) , further undesirable side reactions can occur. These side reactions can form undesirable carbon deposits on the surface of catalysts 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 are favored at higher temperatures, just like the rWGS reaction. Accordingly, because the carbon-producing side reactions (Equations (5) - (7) ) are also endothermic and are favored at higher temperatures, operation at higher temperatures to favor the desired carbon monoxide product can severely impact catalyst lifetime through the deposition of carbon. Given the multiple reactions and competing thermodynamics at play, there remains a need in the art for new rWGS catalysts and processes, especially for integration with Fischer-Tropsch processes. SUMMARY In one aspect, the present disclosure provides for a supported reverse water-gas shift catalyst comprising: a support; nickel, present in an amount in the range of 0.05 to 20 wt%of the catalyst, based on the total weight of the catalyst; and gallium, present in an amount in the range of 0.5 to 20 wt%of the catalyst, based on the total weight of the catalyst. In another aspect, the present disclosure provides for a method of making the catalyst as described herein, the method comprising: providing a support; contacting the support with a liquid comprising one or more nickel-containing compounds and one or more gallium-containing compounds dispersed in a solvent; allowing the solvent to evaporate to provide a catalyst precursor; and calcining the catalyst precursor. In another aspect, the present disclosure provides for a catalyst as described herein made by the method as described herein. In another aspect, the present disclosure provides a method for performing a reverse water-gas shift reaction, the method comprising contacting at a temperature in the range of 250-900℃ a catalyst as described herein with a feed stream comprising CO2 and H2, to provide a product stream comprising CO and H2, the product stream having a lower concentration of CO2 and a higher concentration of CO than the feed stream. In one aspect, the present disclosure provides for a process for performing an integrated Fischer-Tropsch process, the process comprising: providing a first feed stream comprising H2 and CO2; contacting at a first temperature in the range of 250-900℃ and at a first pressure a reverse water-gas shift catalyst with the first feed stream to perform a reverse water-gas shift reaction to provide a first product stream comprising CO and H2, the first product stream having a lower concentration of CO2 and a higher concentration of CO than the first feed stream; contacting at a second temperature and at a second pressure a Fischer-Tropsch catalyst with a secon