US-20260124604-A1 - METHOD FOR PREPARING A GENERALLY SPHERICAL CATALYST PRECURSOR MATERIAL FOR A METHANATION REACTION, SPHERES OBTAINED BY SUCH A METHOD, METHANATION METHOD AND DEVICE

Abstract

The preparation method ( 100 ) for preparing a generally spherical catalyst precursor material comprises: a formation step ( 101 ) for forming a generally spherical support comprising mesoporous alumina (Al 2 O 3 ) or an alumina precursor and having a sphericity factor greater than 0.75, preferably greater than 0.80 and more preferably greater than 0.85, an incorporation step ( 102 ) for incorporating a nickel precursor into the support comprising mesoporous alumina (Al 2 O 3 ) or an alumina precursor by bringing a composition comprising the nickel precursor into contact with the support and a calcination step ( 103 ) for calcining the support incorporating the nickel precursor to at least partially transform the nickel precursor into nickel oxide (NiO) and the alumina precursor into alumina, and subsequently form a solid having a generally spherical shape, the solid being referred to as a “sphere made of a catalyst precursor material for a methanation reaction”.

Inventors

• YILMAZ KARA
• Larissa BRITO
• ARNAUD LAHOUGUE

Assignees

• ENGIE
• ENERCAT - ALSYS GROUP

Dates

Publication Date

20260507

Application Date

20230704

Priority Date

20220707

Claims (20)

1. 1 - 24 . (canceled)
2. 25 . A preparation method for preparing a generally spherical catalyst precursor material for a methanation reaction, comprising: a formation step for forming a generally spherical support comprising mesoporous alumina (Al 2 O 3 ) or an alumina precursor and having a sphericity factor greater than 0.75, preferably greater than 0.80 and more preferably greater than 0.85: an incorporation step for incorporating a nickel precursor into the support comprising mesoporous alumina (Al 2 O 3 ) or an alumina precursor by bringing a composition comprising the nickel precursor into contact with the support; a calcination step for calcining the support incorporating the nickel precursor to at least partially transform the nickel precursor into nickel oxide (NiO) and the alumina precursor into alumina, and subsequently form a solid having a generally spherical shape, the solid being referred to as a “sphere made of a catalyst precursor material for a methanation reaction”; and a step of mechanically treating the spherical support after the step of forming the support, to increase the sphericity factor of the spherical support.
3. 26 . The method according to claim 25 , wherein the mechanical treatment step is performed in a fluidised bed by passing a gas in contact with the spherical support.
4. 27 . The method according to claim 26 , wherein the mechanical treatment step and the calcination step are concurrent and performed in a fluidised bed.
5. 28 . The method according to claim 26 , wherein during the mechanical treatment step performed in a fluidised bed, the gas in contact with the spherical support is an inert gas.
6. 29 . The method according to claim 26 , wherein during the mechanical treatment step performed in a fluidised bed the fluidisation rate is at least two times higher than the minimum fluidisation velocity.
7. 30 . The method according to claim 26 , wherein during the mechanical treatment step performed in a fluidised bed, preferably, the fluidisation rate is at least six times higher than the minimum fluidisation velocity.
8. 31 . The method according to claim 26 , wherein during the mechanical treatment step performed in a fluidised bed the fluidisation rate is at least ten times higher than the minimum fluidisation velocity.
9. 32 . The method according to claim 26 , wherein, after the step of mechanical treatment in a fluidised bed, the step of incorporating a nickel precursor is also performed in the fluidised-bed reactor.
10. 33 . The method according to claim 25 , wherein the mechanical treatment step is performed using a rotating tank configured to generate impacts between the support particles.
11. 34 . The method according to claim 25 , wherein the generally spherical support comprises a hydrated alumina of boehmite type (formula AlOOH).
12. 35 . The method according to claim 25 , wherein the incorporation step comprises a step of impregnating the support with a solution comprising the nickel precursor.
13. 36 . The method according to claim 25 , wherein the step forming the spherical support comprises at least one of: a granulation step, an atomisation step, a step of droplet coagulation.
14. 37 . A device for preparing a generally spherical catalyst precursor material for a methanation reaction, comprising: a means for forming a generally spherical support comprising mesoporous alumina (Al 2 O 3 ) or an alumina precursor and having a sphericity factor greater than 0.75, preferably greater than 0.80 and more preferably greater than 0.85; a means for incorporating a nickel precursor into the support comprising mesoporous alumina (Al 2 O 3 ) or an alumina precursor, by bringing a composition comprising the nickel precursor (Ni) into contact with the support; and a means for calcining the support incorporating the nickel precursor, configured to at least partially transform the nickel precursor into nickel oxide (NiO) and the alumina precursor into alumina, and configured to form a solid having a generally spherical shape, this solid being referred to as a “sphere made of a catalyst precursor material for a methanation reaction”, which device also comprises a means for mechanically treating the spherical support, after the formation of the support, to increase the sphericity factor of the spherical support.
15. 38 . Spheres made of a catalyst precursor material for a methanation reaction, obtained by the method ( 100 , 200 , 300 ) according to claim 25 , wherein they comprise nickel oxide (NiO) and mesoporous alumina (Al 2 O 3 ), the respective proportions of which are, relative to the total mass of these two compounds: NiO: 1 to 50% by mass; and Al 2 O 3 : 50 to 99% by mass.
16. 39 . The spheres made of a catalyst precursor material according to claim 38 , which have a monomodal granulometry with a median diameter of between 100 and 1000 μm, preferably between 200 and 800 μm, and more preferably between 250 and 350 μm.
17. 40 . The spheres made of a catalyst precursor material according to claim 38 , wherein the alumina (Al 2 O 3 ) has a gamma or delta structure and/or wherein the alumina (Al 2 O 3 ) has a mesoporosity corresponding to a median diameter of the pores, determined by Hg intrusion porosimetry, of between 3 and 50 nm, and preferably between 5 and 25 nm.
18. 41 . The spheres made of a catalyst precursor material according to claim 38 , which have a specific surface area of between 50 and 300 m 2 /g, and preferably between 100 and 250 m 2 /g.
19. 42 . A methanation method ( 500 ), comprising: a step of activating, at least partially, spheres made of a catalyst precursor material according to claim 38 into spheres made of a catalytic material; and a step of passing a gas comprising hydrogen (H 2 ) and at least carbon monoxide (CO) and/or carbon dioxide (CO 2 ) in contact with spheres made of a catalytic material.
20. 43 . A method according to claim 42 , which comprises, prior to the gas passage step, a step of constituting the gas comprising at least one of the following steps: pyrolysis of hydrocarbon materials; pyro-gasification of hydrocarbon materials; gasification of hydrocarbon materials; co-electrolysis of CO 2 /H 2 O; water-gas reaction; reverse water-gas reaction; a step of producing a gas rich in hydrogen; a step of producing a gas rich in CO 2 ; and a step of introducing vapour to the gas.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a method and a device for preparing a catalyst precursor material for a methanation reaction, a material obtained by such a method, and a method and a device for a methanation reaction. It applies, in particular, to the field of the conversion of carbon monoxide (CO) and/or carbon dioxide (CO2), in a gas mixture rich in hydrogen, into a mixture rich in methane (CH4), preferably using a fluidised-bed reactor. STATE OF THE ART For the production of a mixture rich in methane (CH4), from the conversion of carbon monoxide (CO) and/or carbon dioxide (CO2) in a gas mixture rich in hydrogen, also called methanation reaction, there are reactors utilising heterogeneous catalysts for the methanation reaction. These heterogeneous catalysts are mainly made of catalytic materials based on nickel (Ni) supported on a support made of alumina (Al2O3). The reactors of the methanation reaction generally operate with a fixed catalytic bed or a fluidised catalytic bed. In current systems, the catalytic materials used in fluidised catalytic bed methanation reactors do not have a good quality of fluidisation, and resistance to attrition is limited. In effect, during the implementation of a methanation reaction in a fluidised-bed reactor, the attrition of particles made of a catalytic material, also called degradation, takes place as a result of mechanical stresses inherent in the hydrodynamics of the fluidisation. In particular, the particles made of a catalytic material form fines following the attrition, which leads to a drop in catalytic performance. These mechanical stresses are due, for example, to mechanical impacts between the particles made of a catalytic material, between these particles and the inner wall of the reactor, or between these particles and elements present in the reactor, such elements being, for example, cooling tubes, chicanes, and/or supports. In practice, this attrition is also the result of the eradication of the angular shapes likely to be present on the catalytic particles. DESCRIPTION OF THE INVENTION The present invention aims to remedy all or part of these drawbacks. To this end, according to a first aspect, the present invention envisions a method for preparing a generally spherical catalyst precursor material for a methanation reaction according to claim 1. Thanks to these provisions, the method makes it possible to obtain a generally spherical catalyst precursor material having a good quality of fluidisation combined with limited attrition. In particular, such a sphericity factor is dependent on the step forming the spherical support. In addition, these provisions also make it possible to obtain a catalyst precursor material on an industrial scale and having high sphericity. Thanks to the mechanical treatment step, an increase in the sphericity of the catalyst material produced by such a method makes it possible to limit angular shapes for the catalytic particles. In this way, the attrition linked to the presence of angular shapes is limited during a fluidised-bed methanation reaction. In some embodiments, the mechanical treatment step is performed in a fluidised bed by passing a gas in contact with the spherical support. Thanks to these provisions, the method makes it possible to improve the quality of the support by eliminating possible surface faults before the step incorporating the nickel precursor. In particular, the fluidised bed plays a role in the progressive removal of surface faults of the support. The fluidisation therefore performs a dynamic polishing of the surface of the catalyst. This optimises the sphericity of the support. In some embodiments, the mechanical treatment step and calcination step are concurrent and preferably performed in a fluidised bed. In some embodiments, during the mechanical treatment step performed in a fluidised bed, the gas in contact with the spherical support is an inert gas. In some embodiments, during the mechanical treatment step performed in a fluidised bed the fluidisation rate is at least two times higher than the minimum fluidisation velocity. In some embodiments, during the mechanical treatment step performed in a fluidised bed, preferably, the fluidisation rate is at least six times higher than the minimum fluidisation velocity. In some embodiments, during the mechanical treatment step performed in a fluidised bed the fluidisation rate is at least ten times higher than the minimum fluidisation velocity. In some embodiments, after the step of mechanical treatment in a fluidised bed, the step of incorporating a nickel precursor is also performed in the fluidised-bed reactor. In some embodiments, the mechanical treatment step is performed using a rotating tank configured to generate impacts between the support particles. In some embodiments, the generally spherical support comprises a hydrated alumina of boehmite type (formula AlOOH). In some embodiments, the incorporation step compr