WO2025008320A1

WO2025008320A1 - Reactor system for sorption-enhanced catalytic reactions with continuous regeneration of adsorbent, and related methods

Info

Publication number: WO2025008320A1
Application number: PCT/EP2024/068543
Authority: WO
Inventors: Miguel MENÉNDEZ SASTRE; Javier Herguido Huerta; Jaime Soler Herrero; Javier LASOBRAS LAGUNA
Original assignee: Universidad de Zaragoza
Current assignee: Universidad de Zaragoza
Priority date: 2023-07-04
Filing date: 2024-07-02
Publication date: 2025-01-09
Anticipated expiration: 2026-01-04

Abstract

The present invention relates to a circulating, fluidized bed, catalytic reactor, wherein the circulating, fluidized bed, catalytic reactor comprises a plurality of catalyst particles and a plurality of adsorbent particles, wherein the plurality of catalyst particles and the plurality of adsorbent particles have different size and/or different density, such that the plurality of catalyst particles and the plurality of adsorbent particles are capable of separating by means of particle segregation; and means for recirculating a solid stream of the plurality of adsorbent particles. The invention also relates to a reactor system that comprises said catalytic reactor, connected to an adsorbent regeneration reactor. Finally, the invention relates to a method for the continuous, selective regeneration of adsorbent particles in a Sorption Enhanced Reaction (SER), and to uses of the reactor system of the invention in the context of specific reactions.

Description

DESCRIPTION

REACTOR SYSTEM FOR SORPTION-ENHANCED CATALYTIC REACTIONS WITH CONTINUOUS REGENERATION OF ADSORBENT, AND RELATED METHODS

FIELD OF THE INVENTION

The present invention relates to the field of catalyst-mediated reactions, more specifically to the field of Sorption-Enhanced Reactions (SER), wherein adsorbent particles are capable of removing a reaction product from the medium, thereby providing a yield larger than the corresponding to the thermodynamic equilibrium in a conventional reactor.

BACKGROUND ART

The instant invention relates to the field of catalyst-mediated reactions, wherein the yield of the catalyst-mediated reaction is limited by the thermodynamic equilibrium. This limitation often results in low yields when the reaction is carried out in a conventional reactor. Low yields make it necessary to separate and recirculate unconverted reactants, which increases operational costs. To solve this issue, several types of reactors may be used, wherein the thermodynamic equilibrium is displaced by the specific separation of a reaction product, either using membrane reactors or though Sorption Enhanced Reaction (SER). Sorption Enhanced Reactions (SER) are catalyst-aided processes which involve, in addition to the catalyst, the use of an adsorbent in order to modify the thermodynamic equilibrium in a chemical reaction, such that the reaction rate is increased.

Fixed bed reactors have been typically used for SER purposes, wherein catalyst solid particles are intimately mixed with adsorbent solid particles. In this type of reactors, the adsorbent becomes saturated with one of the reaction by-products after a certain amount of time and needs to be regenerated. Since the catalyst and adsorbent solid particles are intimately mixed, both catalyst and adsorbent particles are subjected to the same regeneration conditions. This mode of operation has several drawbacks, such as operating in a non-stationary state, which is not industrially desirable, or needing several beds, so that some beds can be in operation while others are undergoing the regeneration process. Importantly, in these reactors, catalyst particles are subjected to the same processes of heating, environmental changes, etc; which are required for the regeneration of the adsorbent. These process conditions can damage the catalyst (deactivation, sintering, etc.). The problem of operating in a non-stationary state is solved by using circulating fluidized bed reactors, wherein the mixture of catalyst and adsorbent solid particles is continuously directed to a second, separate reactor for regeneration of the adsorbent. As in the case of fixed bed reactors, this mode of operation involves that catalyst particles undergo the relatively harsh conditions of the regeneration process and, as a consequence, the risk also exists that the catalyst may be damaged.

Bjornar Arstad et al. (“Continuous hydrogen production by sorption enhanced steam methane reforming (SE-SMR) in a circulating fluidized bed reactor: Sorbent to catalyst ratio dependencies”, Chemical Engineering Journal 189- 190 (2012) 413-421) disclose continuous hydrogen production, which is attained by sorption enhanced steam methane reforming (SE-SMR) using a circulating fluidized bed reactor system that comprises a catalyst (Ni/NiAhOt) and a CO2 adsorbent (calcined natural dolomite). Bjornar Arstad et al. mention catalyst deactivation issues, mainly due to sintering (active surface loss) and/or oxidation. As a solution, they suggest the addition of an active component to the catalyst to prevent catalyst oxidation, and/or the introduction of H2 into the regenerator.

Isabel Martinez et al. (“Performance and operating limits of a sorbent-catalyst system for sorption-enhanced reforming (SER) in a fluidized bed reactor”, Chemical Engineering Science, Volume 205, pp. 94-105, 2019) compare different types of catalyst-sorbent combinations in the context of sorption-enhanced reforming (SER) processes. The authors acknowledge that where the SER process is operated in steady state in a dual fluidized bed system by circulating the solids between two reactors (i.e. , continuous process operation), the sorbent requires regeneration in a highly oxidizing and steam-rich atmosphere. This document addresses the issue of catalyst deactivation due to oxidation while sorbent regeneration takes place but suggests that the problem may be solved by ensuring a minimum presence of H2 in the regenerator.

As shown, catalyst deactivation during the regeneration of adsorbent particles in the context of sorption-enhanced catalytic reactions is a problematic issue in this technical field and the provision of alternative, effective solutions is highly desired.

SUMMARY OF THE INVENTION The instant invention solves the issue of catalyst deactivation by attaining the selective regeneration of adsorbent particles (i.e., independently from catalyst particles) in a reactor set-up that comprises a circulating, fluidized bed, catalytic reactor suitable for carrying out the Sorption Enhanced Reaction (SER) of interest, wherein the reactor can support the selective, continuous flow of adsorbent particles for independent regeneration in a separate reactor. This is achieved in the context of the invention by exploiting the phenomenon of particle separation in binary mixtures of particles with different size and/or different density in a fluidized bed reactor. Accordingly, the instant invention relates to reaction systems and methods that involve Sorption Enhanced Reactions (SER) which are carried out in circulating, fluidized bed, catalytic reactors that allow for the selective, continuous recirculation of the solid adsorbent particles (which are responsible for removing one of the reaction products from the medium), such that the adsorbent particles may be selectively and continuously treated in a separate regeneration reactor. This avoids that the solid catalyst particles unnecessarily undergo the sorbent regeneration treatment and prevents catalyst particle degradation.

Thus, the instant invention relates in a first aspect to a circulating, fluidized bed, catalytic reactor, wherein the circulating, fluidized bed, catalytic reactor comprises a plurality of catalyst particles and a plurality of adsorbent particles, wherein the plurality of catalyst particles and the plurality of adsorbent particles have different size and/or different density, such that the plurality of catalyst particles and the plurality of adsorbent particles are capable of separating by means of particle segregation; and means for recirculating a solid stream of the plurality of adsorbent particles.

In addition, the instant invention relates in a second aspect to a reactor system, wherein the reactor system comprises a circulating, fluidized bed, catalytic reactor according to the first aspect of the invention; and an adsorbent regeneration reactor; wherein the means for recirculating a solid stream of the plurality of adsorbent particles in the circulating, fluidized bed, catalytic reactor are connected to the adsorbent regeneration reactor.

Moreover, in a third aspect the invention relates to a method for the continuous, selective regeneration of adsorbent particles in a Sorption Enhanced Reaction (SER), wherein the method comprises providing a reactor system according to the second aspect of the invention; carrying out the SER in the circulating, fluidized bed, catalytic reactor under conditions that separate the plurality of catalyst particles from the plurality of adsorbent particles; continuously extracting adsorbent particles using the means for recirculating a solid stream of adsorbent particles in the circulating, fluidized bed, catalytic reactor; regenerating the adsorbent particles in the adsorbent regeneration reactor; and returning the regenerated adsorbent particles to the fluidized bed catalytic reactor.

Finally, in a fourth aspect the invention relates to the use of the fluidized bed catalytic reactor according to the first aspect of the invention, or the use of a reactor system according to the second aspect of the invention for carrying out a reaction selected from the group comprising:

Methanol synthesis from CO2, CO, or mixtures of CO2 and CO; and hydrogen;

Dimethyl ether production from CO2, CO, or mixtures of CO2 and CO; and hydrogen;

Synthesis of synthetic natural gas by CO2 hydrogenation or by CO hydrogenation; Fischer-Tropsch hydrocarbon production from syngas;

Hydrogen production from CO + H2O mixtures by water gas shift reaction;

CO production from CO2 + H2 mixtures by reverse water gas shift reaction;

Hydrogen production from natural gas or hydrocarbons by steam reforming (CH4 + 2H₂O CO₂ + 4H₂, CH₄ + H₂O CO + 3H₂, or C_nH_m + 2n H₂O n CO₂ + (m/2+2n) H2); and

Desulfurization of organic compounds such as naphtha, liquefied petroleum gases and, in general, petroleum derivatives that can be hydrogenated in the gas phase.

BRIEF SUMMARY OF THE FIGURES

- Figure 1 shows a reactor system comprising a circulating, fluidized bed, catalytic reactor, and an adsorbent regeneration reactor.

- Figure 2 shows catalyst and adsorbent concentration profiles in the circulating, fluidized bed, catalytic reactor bed. Grey colour variation (from dark to light) of the adsorbent particles indicate concentration changes of the adsorbed compound.

- Figure 3 shows variation of concentration in an experimental set up wherein the catalyst particles are flotsam and wherein the adsorbent particles are jetsam.

- Figure 4 shows variation of concentration in an experimental set up wherein the catalyst particles are jetsam and wherein the adsorbent particles are flotsam.

- Figure 5 shows an experimental set up wherein the reactor has different diameters in different sections along its height.

- Figure 6 shows an experimental set up wherein the reactor comprises a stream of an oxidant to regenerate the catalyst particles. DETAILED DESCRIPTION

As explained above, the instant invention solves the issue of catalyst deactivation due to the conditions of the absorbent regeneration process by attaining the selective regeneration of adsorbent particles (i.e., independently from catalyst particles) in a reactor set-up that comprises a circulating, fluidized bed, catalytic reactor suitable for carrying out the Sorption Enhanced Reaction (SER) of interest, wherein the reactor can support the selective, continuous flow of adsorbent particles for independent regeneration in a separate reactor. This is achieved in the context of the invention by exploiting the phenomenon of particle separation in binary mixtures of particles with different size and/or different density in a fluidized bed reactor. Accordingly, the instant invention relates to reaction systems and methods that involve Sorption Enhanced Reactions (SER) which are carried out in circulating, fluidized bed, catalytic reactors that allow for the selective, continuous recirculation of the solid adsorbent particles (which are responsible for removing one of the reaction products from the medium), such that the adsorbent particles may be selectively and continuously treated in a separate regeneration reactor. This avoids that the solid catalyst particles unnecessarily undergo the sorbent regeneration treatment and prevents catalyst particle degradation. Thus, the invention relates to several aspects, as disclosed herein below.

Circulating, fluidized bed, catalytic reactor, and reactor system of the invention

The instant invention relates in a first aspect to a circulating, fluidized bed, catalytic reactor, wherein the circulating, fluidized bed, catalytic reactor comprises:

- a plurality of catalyst particles and a plurality of adsorbent particles, wherein the plurality of catalyst particles and the plurality of adsorbent particles have different size and/or different density, such that the plurality of catalyst particles and the plurality of adsorbent particles are capable of separating by means of particle segregation; and

- means for recirculating a solid stream of the plurality of adsorbent particles.

As used herein, the term “reactor” or “chemical reactor” refers to a vessel designed to contain a controlled chemical reaction, such that the reaction takes place within the reactor (i.e., inside the reactor), in conditions which can be monitored and controlled for safety and efficiency. Chemical reactors are typically designed to produce the highest possible product yield while requiring the least amount of operating costs. Normal operating expenses include energy input, energy removal, costs of raw materials, and the like. In the context of the present invention, the chemical reactor is a fluidized bed reactor. The term “fluidized bed reactor” or FBR, as used herein, refers to a type of reactor wherein a fluid (gas or liquid) is passed through a solid particulate material at speeds that are sufficiently high to suspend the solid in a process known as fluidization and cause the solid to behave as though it were a fluid. The chemical reactor of the invention is a circulating reactor. As used herein, the term “circulating” refers to chemical reactors wherein a fraction of the particulate solids is continuously extracted from the reaction vessel, transferred between different reactors having distinctive reactive environments, and finally returned to the original chemical reactor after controlled material handling (e.g., material regeneration). In the context of the instant invention, the chemical reactor is a catalytic reactor in the sense that the chemical reaction that takes place within the chemical reactor is a catalyst assisted reaction.

As indicated above, the circulating, fluidized bed, catalytic reactor comprises a plurality of catalyst particles and a plurality of adsorbent particles. The plurality of catalyst particles and adsorbent particles are in the solid phase. The catalyst particles comprise the chemical catalyst that assists the chemical reaction (i.e., the catalyst increases the rate of the chemical reaction), whereas the adsorbent particles are capable of selectively adsorbing one of the reaction products, thereby affecting the reaction rate and the thermodynamic equilibrium of the chemical reaction of interest. In particular embodiments of the invention, the catalyst is selected from the group consisting of CuO/ZnO/AhCh, or CuO/ZnO/ZrCh, Cu/CeC>2, Cu/TiC>2, or Pd/ZnO or Pd/ln2Oa orAu/ZrCh (with or without a doping agent, such as for example Ga); an alumina, a silica-alumina or a zeolite (for example, ZSM-5 or Zeolite Y) ; Fe or Co, or Ni or Ru on a SiC>2 or AI2O3 support and a promoter (eg K or Cu); Ni- Fe/AhCh, Ni/AhCh; iron oxides, cobalt oxides, chromium oxides, nickel oxides, copper oxides or carbon oxides, ruthenium, supported on materials such as alumina, silica or zeolites, and combinations thereof. In particular embodiments of the invention, the adsorbent is selected from the group consisting of alumina, silica alumina, FCC catalyst, zeolite, as for example zeolite 3A, zeolite 4A, zeolite 5A, zeolite 13X, montmorillonite, CaO, MgO, calcined dolomite, USY zeolite on a silica-alumina support, and combinations thereof.

As indicated above, the plurality of catalyst particles and the plurality of adsorbent particles have different size and/or different density, such that the plurality of catalyst particles and the plurality of adsorbent particles are capable of separating. In particular embodiments of the invention, the plurality of catalyst particles and the plurality of adsorbent particles correspond to Geldart classification types A and/or B (D. Geldart, “Types of Gas Fluidization”, Powder Technology, 7 (1973), pp. 285-292). In an embodiment of the invention, the plurality of catalyst particles are particles in Geldart Group A and the plurality of adsorbent particles are particles in Geldart Group B. In another embodiment of the invention, the plurality of catalyst particles are particles in Geldart Group B and the plurality of adsorbent particles are particles in Geldart Group A. Particles typically used in fluidized beds are Group A powders. Geldart Group A particles tend to be aeratable and fluidize well. Group A particle sizes range from 30pm to 150pm, and particle densities are in the range of about 1500kg/m³ or less. Geldart Group B particles have a particle size range of 150pm to 2000pm (i.e., 0.15mm to 2.00mm) and particle densities in the range from 1400- 4000kg/m³. Particles larger than 1000 micrometres, with densities around 1000 kg/m³, are Geldart Group D, and they fluidize in the form of jets, so they are not very suitable in the context of the instant invention. However, under particular experimental set-ups (e.g., reactor beds with different diameter in different sections), Geldart Group D particles can be used, so that the Geldart Group D particle is fluidising in the smaller diameter section and segregation would occur in the upper zone, with a larger diameter. Geldart Group D particles can be used in a mostly Geldart Group B bed. Thus, in particular embodiments, the plurality of catalyst particles and the plurality of adsorbent particles correspond to Geldart classification types B and/or D (Rovero et al., “Optimization of Spouted Bed Scale-Up by Square-Based Multiple Unit Design”, Advances in Chemical Engineering 2012, pp. 405- 434; Cocco et al., “Introduction to Fluidization”, American Institute of Chemical Engineers, AIChE, CEP 2014, pp. 21-29). In particular embodiments of the invention, the term particle size refers to mean particle diameter.

The particles used in the context of the invention may be of any form and shape. However, essentially spherical particles are typically used, since elongated or flat particles are not easy to use in fluidized beds. Thus, in a particular embodiment, the plurality of catalyst particles and the plurality of adsorbent particles are essentially spherical particles.

In particular embodiments of the invention, the plurality of catalyst particles are particles in Geldart Group A with particle sizes in the range from 30pm to 150pm, and particle densities in the range of about 1500kg/m³ or less, such as for example 500-1500kg/m³. In particular embodiments, the plurality of catalyst particles are particles with particle sizes of 30pm, 40pm, 50pm, 60pm, 70pm, 80pm, 90pm, 100pm, 110pm, 120pm, 130pm, 140pm, or 150pm. In particular embodiments, the plurality of catalyst particles are particles with particle densities of about 500kg/m³, of about 600kg/m³, of about 700kg/m³, of about 800kg/m³, of about 900kg/m³, of about 1000kg/m³, of about 1100kg/m³, of about 1200kg/m³, of about 1300kg/m³, of about 1400kg/m³, or of about 1500kg/m³. In particular embodiments of the invention, the plurality of catalyst particles are particles in Geldart Group B with particle sizes in the range from 150pm to 2000pm, and particle densities in the range of about 1400-4000kg/m³. In particular embodiments, the plurality of catalyst particles are particles with particle sizes of 150pm, 200pm, 250pm, 300pm, 350pm, 400pm, 450pm, 500pm, 550pm, 600pm, 650pm, 700pm, 750pm, 800pm, 850pm, 900pm, 950pm, 1000pm, 1100pm, 1200pm, 1300pm, 1400pm, 1500pm, 1600pm, 1700pm, 1800pm, 1900pm, or of 2000pm. In particular embodiments, the plurality of catalyst particles are particles with particle densities of about 1400kg/m³, of about 1600kg/m³, of about 1800kg/m³, of about 2000kg/m³, of about 2200kg/m³, of about 2400kg/m³, of about 2600kg/m³, of about 2800kg/m³, of about 3000kg/m³, of about 3200kg/m³, of about 3400kg/m³, of about 3600kg/m³, of about 3800kg/m³, or of about 4000kg/m³.

In particular embodiments of the invention, the plurality of adsorbent particles are particles in Geldart Group A with particle sizes in the range from 30pm to 150pm, and particle densities in the range of about 1500kg/m³ or less, such as for example 500-1500kg/m³. In particular embodiments, the plurality of adsorbent particles are particles with particle sizes of 30pm, 40pm, 50pm, 60pm, 70pm, 80pm, 90pm, 100pm, 110pm, 120pm, 130pm, 140pm, or 150pm. In particular embodiments, the plurality of adsorbent particles are particles with particle densities of about 500kg/m³, of about 600kg/m³, of about 700kg/m³, of about 800kg/m³, of about 900kg/m³, of about 1000kg/m³, of about 1100kg/m³, of about 1200kg/m³, of about 1300kg/m³, of about 1400kg/m³, or of about 1500kg/m³. In particular embodiments of the invention, the plurality of adsorbent particles are particles in Geldart Group B with particle sizes in the range from 150pm to 2000pm, and particle densities in the range of about 1400-4000kg/m³. In particular embodiments, the plurality of adsorbent particles are particles with particle sizes of 150pm, 200pm, 250pm, 300pm, 350pm, 400pm, 450pm, 500pm, 550pm, 600pm, 650pm, 700pm, 750pm, 800pm, 850pm, 900pm, 950pm, 1000pm, 1100pm, 1200pm, 1300pm, 1400pm, 1500pm, 1600pm, 1700pm, 1800pm, 1900pm, or of 2000pm. In particular embodiments, the plurality of adsorbent particles are particles with particle densities of about 1400kg/m³, of about 1600kg/m³, of about 1800kg/m³, of about 2000kg/m³, of about 2200kg/m³, of about 2400kg/m³, of about 2600kg/m³, of about 2800kg/m³, of about 3000kg/m³, of about 3200kg/m³, of about 3400kg/m³, of about 3600kg/m³, of about 3800kg/m³, or of about 4000kg/m³.

In particular embodiments of the invention, the particle diameter ratio (catalyst particle diameter to adsorbent particle diameter, or adsorbent particle diameter to catalyst particle diameter, wherein the higher particle diameter value is always the numerator and wherein the lower particle diameter value is always the denominator) is equal to or higher than 1 .5. In particular embodiments, the particle diameter ratio is between 1.5 to 33.3, between 2.0 to 20.0, or between 3.0 to 10.0. In particular embodiments, the particle diameter ratio is 1 .5, 2.0, 2.5, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 15.0, 20.0, 25.0, 30.0, or 33.3. In particular embodiments, if one particle (catalyst or adsorbent) has a 50% or more higher density than the other, instead of the particle diameter ratio, the ratio of particle diameters times the square root of the ratio of densities should be used. The difference in density in the context of the instant invention cannot be very large (both the adsorbent and the catalyst are porous solids, with similar porosity values, because if they are too porous, they do not have mechanical resistance and if they are not porous there is no mass transfer within the particle). In addition, the effect of density is smaller, since it affects in proportion to the square root of the ratio of densities, while the particle diameter linearly affects (approximately) the minimum fluidization velocity.

As explained above, the plurality of catalyst particles and the plurality of adsorbent particles have different size and/or different density, such that the plurality of catalyst particles and the plurality of adsorbent particles are capable of separating by means of particle segregation. Separation by means of particle segregation involves that one type of particles will separate towards the top end of the solid particle mixture (flotsam) whereas the other type of particles will separate towards the bottom end of the solid particle mixture (jetsam) in the reactor. Thus, in a particular embodiment, the plurality of catalyst particles is capable of separating as jetsam and the plurality of adsorbent particles is capable of separating as flotsam. Alternatively, in another particular embodiment, the plurality of catalyst particles is capable of separating as flotsam and the plurality of adsorbent particles is capable of separating as jetsam.

In particular embodiments of the instant invention, the proportion of catalyst particles versus adsorbent particles is between 90:10 and 10:90. In particular embodiments, the proportion of catalyst particles versus adsorbent particles is 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80, 10:90.

In a particular embodiment of the invention, the reactor comprises a reactor vessel, wherein said reaction vessel has different diameters in at least two different sections along the vessel height. In a particular embodiment, the diameter of the different sections of the reactor vessel decreases from top to bottom. For example, in a reactor vessel with two sections, the diameter of the top section is larger than the diameter of the bottom section. In an alternative embodiment, the diameter of the different sections of the reactor vessel increases from top to bottom. For example, in a reactor vessel with two sections, the diameter of the top section is smaller than the diameter of the bottom section. Variations in section diameter are associated so several advantages. If the top section has a larger diameter, it is possible to have more segregation at the top and good mixing at the bottom of the reaction vessel. Thus, the purest adsorbent stream (in this case, the flotsam) would be removed from the top. In the lower part, there would be a more isothermal system, which is advantageous to avoid hot spots, due to the exothermicity of the reaction (for example, in CO2 hydrogenation). If the section is larger at the bottom, it would allow segregation at the bottom. This would allow for the removal of the purest adsorbent stream (in this case, the jetsam) from the bottom of the reaction vessel. Furthermore, by adding cold adsorbent on top, the exothermicity of the reactions can be compensated.

In another particular embodiment of the invention, the reactor further comprises an inlet stream of an oxidizing agent, such that catalyst regeneration can take place in the reactor, in agreement with the systems already known in the art. Oxidizing agents can be used in reactions in which coke can be formed on the catalyst, deactivating it, such as steam reforming if the steam/ carbon ratio is low. Suitable oxidizing agents include oxygen, water vapor or CO2. In a further embodiment, the two-zone fluidized bed reactor may be combined with an inlet stream of an oxidizing agent. In a particular embodiment, the regeneration of the catalyst involves the addition of an oxidizing agent at the bottom of the reactor, while the reactants for the specific reaction are fed at an intermediate point of the reactor. In this embodiment, two zones with different atmospheres can be distinguished within the same reactor.

In a second aspect, the invention refers to a reactor system, wherein the reactor system comprises: a circulating, fluidized bed, catalytic reactor according to the first aspect of the invention; and an adsorbent regeneration reactor; wherein the means for recirculating a solid stream of the plurality of adsorbent particles in the circulating, fluidized bed, catalytic reactor are connected to the adsorbent regeneration reactor.

In the context of the invention the term “means for recirculating” in connection with a solid stream of a plurality of adsorbent particles refers to devices or constructions that allow the exit and entry of solids into and from the catalytic reactor. Said means for recirculating may take any suitable form known in the art, such as, for example, overflow systems, tubes, loop seals, standpipes, II valves, J valves, L valves or loops, and the like. The circulating, fluidized bed, catalytic reactor, and the adsorbent regeneration reactor are connected by said means for recirculating, which allow the transfer of fluidised solid particles between the two, generally avoiding gas leakage between both reaction and regeneration atmospheres. In particular embodiments, the reactors may be interconnected by means of a riser/ cyclone system and two loop seals.

The adsorption regeneration reactor can take any form that is suitable for the desorption of the adsorbed reaction by-product, and thus is suitable for adsorbent regeneration. In particular embodiments of the invention, the adsorbent regeneration reactor is a fluidized bed reactor or a pneumatic transport reactor.

Method for the continuous, selective regeneration of adsorbent particles

A method for the continuous, selective regeneration of adsorbent particles in a Sorption Enhanced Reaction (SER), wherein the method comprises: providing a reactor system according to the instant invention; carrying out the SER in the circulating, fluidized bed, catalytic reactor under conditions that separate the plurality of catalyst particles from the plurality of adsorbent particles; continuously extracting adsorbent particles using the means for recirculating a solid stream of adsorbent particles in the circulating, fluidized bed, catalytic reactor; regenerating the adsorbent particles in the adsorbent regeneration reactor; returning the regenerated adsorbent particles to the fluidized bed catalytic reactor.

In the context of the instant invention, the parameters that condition the separation of catalyst and adsorbent particles include, but are not limited to, fluid velocity (i.e., gas velocity), fluid density and viscosity (i.e., gas density and viscosity), catalyst to adsorbent ratios (i.e., percentage of each solid in the mixture), catalyst and adsorbent particle diameter, catalyst and adsorbent particle density, and reactor section changes with height.

In particular embodiments, separation by means of segregation is achieved when the fluid velocity is 1-4 times, 1-3 times, or 1-2 times the minimum fluidization velocity of the mixture. In particular embodiments, separation by means of segregation is achieved when the fluid velocity is 1 times the minimum fluidization velocity of the mixture (i.e., when the fluid velocity is equal to the minimum fluidization velocity of the mixture), 1.2 times the minimum fluidization velocity of the mixture, 1.4 times the minimum fluidization velocity of the mixture, 1 .6 times the minimum fluidization velocity of the mixture, 1.8 times the minimum fluidization velocity of the mixture, 2.0 times the minimum fluidization velocity of the mixture, 2.2 times the minimum fluidization velocity of the mixture, 2.4 times the minimum fluidization velocity of the mixture, 2.6 times the minimum fluidization velocity of the mixture, 2.8 times the minimum fluidization velocity of the mixture, 3.0 times the minimum fluidization velocity of the mixture, 3.2 times the minimum fluidization velocity of the mixture, 3.4 times the minimum fluidization velocity of the mixture, 3.6 times the minimum fluidization velocity of the mixture, 3.8 times the minimum fluidization velocity of the mixture, or 4.0 times the minimum fluidization velocity of the mixture.

In the context of the instant invention, the minimum fluidization velocity (Umf) of the mixture can be defined as the fluid velocity at which the drag force of the upward moving fluid (gas or liquid) becomes equal to the weight of the solid particles within the reactor bed.

The step of “continuously extracting adsorbent particles” refers to the continuous and selective extraction of a stream of adsorbent particles from the catalytic reactor. As used herein, the stream of adsorbent particles is considered a selective extraction if said stream contains at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99% of adsorbent particles. In particular embodiments, the stream of adsorbent particles contains 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91 %, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% of adsorbent particles.

The step of “regenerating the adsorbent particles” in the adsorbent regeneration reactor involves the regeneration of at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99% of the adsorbent particles that are circulated towards the regeneration reactor. In particular embodiments, the stream of regenerated adsorbent particles contains a 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81 %, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% of adsorbent particles that have been regenerated (i.e., where the adsorbed reaction by-product has been desorbed).

Use of the circulating, fluidized bed, catalytic reactor, and reactor system of the invention Finally, in a fourth aspect the invention relates to the use of the fluidized bed catalytic reactor according to the first aspect of the invention, or the use of a reactor system according to the second aspect of the invention for carrying out a reaction selected from the group comprising:

Methanol synthesis from CO2 and hydrogen, wherein the methanol synthesis reaction proceeds via the reverse water-gas shift reaction (RWGS, CO2 + H2 CO + H2O), which is followed by CO hydrogenation to methanol via HCO (CO + 2H2 CH3OH), such that the global reaction is (CO2 + 3H2 CH3OH + H2O). Performance can be increased with an H2O adsorbent, such as for example zeolite A;

Dimethyl ether (DME) production from CO2 and hydrogen, wherein methanol is first produced from the hydrogenation of carbon dioxide (CO2 + 3H2 CH3OH + H2O) followed by DME formation via alcohol dehydration (2CH3OH CH3OCH3 + H2O), such that the global reaction is (2CO2 + 6H2 CH3-O-CH3 + 3H2O). Performance can be increased with an H2O adsorbent;

Synthesis of synthetic natural gas by CO2 hydrogenation (CO2 + 4H2 CH4 + 2H2O) or synthesis of synthetic natural gas by CO hydrogenation (CO + 3H2 CH4 + H2O), via methanation reactions. Performance can be increased with an H2O adsorbent;

Fischer-Tropsch hydrocarbon production from syngas (i.e., syngas is mixtures of CO, CO2 and hydrogen), wherein the reaction may be represented as (nCO + 2nH2 — > CnF^n + nH₂O) y/o (nCO2 + 3nH2 — > CnF^n + 2H2O). Performance can be increased with an H2O adsorbent;

Hydrogen production from CO + H2O mixtures by water gas shift reaction, wherein the reaction is (CO + H2O CO2 + H2). Performance can be increased with a CO2 adsorbent, such as CaO. An H2 adsorbent can also be used;

CO production from CO2 + H2 mixtures by reverse water gas shift reaction, wherein the reaction is (CO2 + H2 CO + H2O). Performance can be increased with an H2O adsorbent;

Hydrogen production from natural gas or hydrocarbons by steam reforming, wherein the reaction may be represented as (CH4 + 2H2O CO2 + 4H2) or (C_nH_m + 2n H2O n CO2 + (m/2+2n) H2). In this case, a CO2 adsorbent can be used to increase the yield and obtain higher purity hydrogen; and

Desulfurization of organic compounds such as naphtha, liquefied petroleum gases and, in general, petroleum derivatives that can be hydrogenated in the gas phase. In this case, a sorbent such as ZnO should be added, which would remove the H2S formed and therefore allow a more complete desulfurization to be achieved. The catalyst to be used will depend on the specific reaction. The catalyst can be any of those described in the state of the art for the reaction of interest. Thus, if methanol synthesis is carried out, CuO/ZnO/AhCh or CuO/ZnO/ZrCh, Cu/CeCh, Cu/TiCh, or Pd/ZnO or Pd/ln2Oa or Au/ZrC>2 catalysts (any of which can be used with a doping agent, such as e.g., Ga) or any other catalysts described in the state of the art for this reaction. If the reaction of interest is the formation of dimethyl ether, the catalyst will be a combination of a catalyst for the synthesis of methanol with an acid catalyst that can be an alumina, a silica-alumina or a zeolite, for example ZSM-5, Zeolite Y or any other acid catalyst described in the state of the art. If the reaction is Fischer-Tropsch, the catalyst can be Fe or Co, or Ni or Ru on a SiC>2 or AI2O3 support and a promoter (eg K or Cu) or any other of the catalysts described in the state of the art. If the reaction is to reform hydrocarbons with steam, the catalyst can be Ni/AhCh or any other of the catalysts described in the state of the art. If the reaction is the hydrogenation of CO or CO2 to obtain synthetic natural gas, the catalyst can be Ni/AhOa or any other of those described in the state of the art. If the reaction is the production of CO from CO2+H2 mixtures by the reverse reaction of water gas shift, the catalyst can be iron oxides, cobalt oxides, chromium oxides, nickel oxides, copper oxides or carbon oxides, ruthenium, supported on materials such as alumina, silica or zeolites.

In a particular embodiment of the invention, the reaction is selected from the group consisting of:

Methanol synthesis from CO2, CO, or mixtures of CO2-CO; and hydrogen;

Dimethyl ether production from CO2, CO, or mixtures of CO2-CO; and hydrogen;

Synthesis of synthetic natural gas by CO2 hydrogenation;

Synthesis of synthetic natural gas by CO hydrogenation;

Fischer-Tropsch hydrocarbon production from syngas; and

CO production from CO2 + H2 mixtures by reverse water gas shift reaction.

All the terms and embodiments described anywhere in this document are equally applicable to all aspects of the invention. It should be noted that, as used in the specification and in the appended claims, the singular forms “a”, “an”, and “the” include their plural referents unless the context clearly indicates otherwise. Similarly, the term “comprises” or “comprising” as used herein also describes “consists of” or “consisting of” in accordance with generally accepted patent practice.

EXAMPLES The following invention is hereby described by way of the following examples, which are to be construed as merely illustrative and not limitative of the scope of the invention.

Example 1 : Reactor system for continuous regeneration of adsorbent particles

The reactor system of the instant invention is characterized by comprising a catalytic reactor with two different solids (catalyst and adsorbent solid particles) of different particle size and/or different density within the fluidized bed, such that the different solids tend to segregate. That is, one of them tends to rise to the upper part of the fluidized bed (flotsam) whereas the other tends to fall to the lower part (jetsam). The solid particles of the invention typically correspond to Geldart classification types A and/or B (D. Geldart, “Types of Gas Fluidization”, Powder Technology, 7 (1973), pp. 285-292). The content of adsorbent particles in relation to the total amount of solids is between 10-90%. The selection of suitable particle sizes and/or densities for each of the solids results in efficient segregation, thus allowing for the specific removal of the adsorbent in a continuous manner, wherein a solid stream is removed at a point where the adsorbent concentration is much higher than the catalyst concentration. These adsorbent particles are highly saturated in one of the reaction by-products. As a result, the removal of adsorbent particles loaded with one of the reaction by-products effectively displaces the thermodynamic equilibrium of the chemical reaction of interest that takes place within the reaction vessel.

Figure 1 shows a schematic representation of the reactor system of the invention, wherein the reactor system comprises a fluidized bed catalytic reactor [1] that incorporates means for the continuous recirculation of solid adsorbent particles [2A] [2B], so that said solid adsorbent particles remove one of the reaction products from the medium and increases the conversion of reagents in an in-coming stream [4] to the desired product in an out-going stream [5], Said reactor is characterized by containing two different solids within the fluidized bed: a first solid that acts as a catalyst [3] and a second solid that acts as an adsorbent [2], in such a way that the adsorbent is fed through one end of the reactor bed [6], and exits through the opposite end of the reactor bed [7], while the catalyst remains for the most part within the reactor bed. This effect can be achieved by applying the phenomenon of segregation of solids in a fluidized bed. Segregation takes place when two solids with different density and/or different particle size are mixed within a fluidized bed such that, under certain operating conditions, one of the solids tends to raise to the top end of the reaction bed, while the second solid sinks towards the bottom end of the reaction vessel. Thus, using an adequate particle size for each solid, segregation in the fluidized bed can be used to selectively remove adsorbent particles in a continuous manner.

Under these experimental conditions, a stream of adsorbent solid particles is removed at a point where the concentration of the adsorbent is significantly higher than the concentration of the catalyst. In this experimental system, adsorbent particles with a high degree of saturation in the adsorbed substance [2A] pass through a first transfer line for solids, which is equipped with a pneumatic seal [8] and which is also fluidized with a secondary current of a suitable fluid [9], and into a regeneration reactor [10], The regeneration reactor can be a fluidized bed reactor or a pneumatic transport reactor. The desorption of the reaction product occurs within the regeneration reactor [10], and the regenerated adsorbent particles [2B] are dragged by a current of a sweeping gas [11], After the separation of both phases, i.e. , the adsorbent particle [2B] solids and the sweeping gas [11] by means of a cyclone [13] (or any similar unit), the sweeping gas is released [12] while the adsorbent solid [2B] is returned to the main reactor [1] through a second transfer line equipped with a pneumatic seal [14] and which is also fluidized with a further secondary current of a suitable fluid [15], A schematic representation of the catalyst and adsorbent particle distribution within the catalytic reactor bed can be seen in Figure 2.

The catalytic reactor set-up may be configured differently depending on the direction of separation of catalyst and adsorbent particles (i.e., depending which particle is jetsam and which particle is flotsam). Figure 3 and figure 4 show schematic representations of two different types of experimental set-up which are possible under the instant invention.

Figure 3 shows a particle distribution wherein the adsorbent particles act as jetsam and sink towards the bottom of the reactor, from where they can be selectively circulated towards the regeneration reactor and subsequently returned to the top end of the catalytic reactor. Thus, under this particular configuration of the catalytic reactor of the invention, the highly saturated adsorbent particles tend to fall to the lower part (jetsam) of the fluidized bed catalytic reactor and, thus, the saturated adsorbent particles are extracted from the bottom end of the reactor tank, whereas regenerated adsorbent particles are fed back into the top end of the reactor tank.

Figure 4 shows an alternative particle distribution wherein the adsorbent particles act as flotsam and can be retrieved from the top end of the reactor, from where they can be selectively circulated towards the regeneration reactor and subsequently returned to the bottom end of the catalytic reactor. Under this alternative configuration of the catalytic reactor of the invention, highly saturated adsorbent particles tend to rise to the upper part (flotsam) of the fluidized bed catalytic reactor and, thus, the adsorbent particles are extracted from the top end of the reactor tank, whereas regenerated adsorbent particles are fed back into the bottom end of the reactor tank.

The reactor system of the instant invention also allows for further modifications. Figure 5 shows an experimental set up of the reactor system wherein the catalytic reactor has different diameter in different sections along the height of the reactor vessel (in the example shown in figure 5, the diameter of the upper section is larger than the diameter of the lower section of the reaction vessel). This configuration enables different gas speeds between the lower zone and the upper zone of the reaction vessel, which brings advantages during the operation of the reactor, such as better solid-gas contact in the upper zone of the reactor vessel and better separation in the lower zone of the reactor vessel.

The catalytic reactor of the invention may also incorporate an inlet stream of an oxidizing agent, with the aim to continuously regenerate the catalyst within the catalytic reactor. This solution may also be combined with the two-zone fluidized bed reactor described above, in agreement with the system described in W02009153382 A1. In this example, the regeneration of the catalyst involves the addition of an oxidizing agent at the bottom of the reactor, while the reactants for the specific reaction are fed at an intermediate point of the reactor. In this experimental configuration, two zones with different atmospheres can be distinguished within the same reactor: a first zone, wherein the Sorption-Enhanced Reaction (SER) takes place, and a second zone, wherein the regeneration of the catalyst due to the action of the oxidizing agent takes place. For example, in steam reforming of hydrocarbons with small partial pressure of water, the Ni/AhCh catalyst is deactivated by coke. It is possible to add a catalyst regeneration in situ with an oxidizing gas, such as O2, CO2 or H2O, feeding it to the bottom of the reactor, regenerating the catalyst in the lower part of the reactor and making the reaction in the upper part of the reactor. Examples of reaction and regeneration simultaneously in a fluidized bed (but without sorption enhanced reaction) are described in the article by Herguido and Menendez (2017, Current Opinions in Chemical Engineering). This reaction-enhancing effect due to the oxidizing agent is combined, in the reactor system of the invention, with the increased performance due to the use and continuous regeneration of an adsorbent. A schematic representation of this type of configuration is shown in figure 6, wherein the reagents [4] are introduced via a fluidic stream at a medium height in the fluidized bed (e.g., between the different zones with different diameter), and wherein the stream of the oxidant agent [16] to regenerate the catalyst particles is introduced from the bottom of the catalytic reactor.

Example 2: The mixing index (M.l.) depends on gas flow rates

This example serves to illustrate how a mixture of catalyst and adsorbent can be segregated in a fluidized bed at a suitable rate. The mixing index (M.l.) shall be used as a measure of efficient mixing or separation. The mixing index is calculated as:

Wherein: 0 and H indicate the zero height position, and the total height position of the reactor bed, respectively;

Xj ’. solid concentration at each height in a fully segregated bed (0 or 1 , depending on whether the solid is flotsam or jetsam, i.e. , whether the upper or lower part of the reactor bed is being considered);

Xj’. real value of solid concentration at each height; and Xjo. average value of solid concentration.

Therefore, M.l. has a value of 1 in a fully mixed bed and a value of 0 in a fully segregated bed.

2. 1: 50-50% v/v catalyst-adsorbent mixtures, 1.75x minimum fluidization velocity

A 50% (v/v) mixture of a methanol catalyst with a particle size between 75-150 pm and an adsorbent with a particle size between 200-315 pm is placed in a catalytic reactor bed with a diameter of 2.8 cm and a gas flow rate of 1115 mL/min is fed for 5 minutes, which is 1.75 times the minimum fluidization velocity of the mixture (In all the examples, gas flow rates are given at standard temperature and pressure, i.e. 0°C and 1 bar). After 5 minutes, the gas flow in the reactor bed is cut off, freezing the solids distribution within the reactor bed and fractions of the solid particle mixture are taken at different heights of the reactor bed. Figure 7 shows how the mixture of both solids is segregated in the middle of the reactor bed, obtaining an M.l. = 0.366. The solids mixture in the lower part of the reactor bed contains 95% adsorbent.

2.2: 50-50% v/v catalyst-adsorbent mixtures, 5x minimum fluidization velocity A 50% (v/v) mixture of a methanol catalyst with a particle size between 75-150 pm and an adsorbent with a particle size between 200-315 pm is placed in a catalytic reactor bed with a diameter of 2.8 cm and a gas flow rate of 3185 mL/min is fed for 5 minutes, which is 5 times the minimum fluidization velocity of the mixture (In all the examples, gas flow rates are given at standard temperature and pressure, i.e. 0°C and 1 bar). After 5 minutes, the gas flow is cut off, freezing the solids distribution within the reactor bed and fractions of the solid particle mixture are taken at different heights of the reactor bed. Figure 8 shows how the mixture of both solids remains constant throughout the entire particle bed without appreciating segregation, which is corroborated with an M.l. = 0.965

2.3: 30-70% v/v catalyst-adsorbent mixtures, 2x minimum fluidization velocity

This example serves to illustrate how an adsorbent can be fed continuously through the top of the particle bed, and how the output stream composition and concentration profiles are over time. In this case, a mixture of 30% of a methanol catalyst with a particle size between 75-150 pm, and 70% of an adsorbent with a particle size between 200-315 pm is placed in a 2.4 cm diameter bed, which is fed a gas flow rate of 1431 N mL/min for 260 minutes, 2 times the minimum fluidization velocity of the mixture at 70% adsorbent and 6.85 g/min of adsorbent. At the end of the 260-minute experimental timeframe, the gas flow is cut off, freezing the solids distribution within the reactor bed and fractions of the solid particle mixture are taken at different heights of the reactor bed. The particle distribution results at different reactor heights are as follows:

The concentration profile of catalyst and adsorbent is shown in figure 9. Segregation occurs below 12 cm, obtaining <1% catalyst (flotsam) in the lower part.

2.4: Distribution of mixing index

The above results may be used to prepare a graphical representation of mixing index (M.l.) as a function of fluid velocity, expressed as X times the minimum fluidization velocity (U_mf) of the mixture (X U_mf mixture). Figure 10 shows one such representation for a 50% (v/v) mixture of a catalyst and an adsorbent in a catalytic reactor, wherein the mixing index is calculated as lntegral(abs(x-x mean))/ integral(abs(x*-x mean)), where the integrals are calculated over the bed height, "abs" means absolute value, "x" is the concentration of jetsam at each point, "x mean" is the average concentration of jetsam in the reactor bed and "x*" the concentration that would exist at each point if it were totally segregated. This mixing index is 1 when the bed is totally segregated and 0 if it is totally mixed. This graph is obtained forx mean=0.5, which corresponds to a value of minimum fluidization velocity (U_mf) of the mixture U_mf mixture= 95.63 cm³/cm²*min.

Example 3: Theoretical simulation of the effect of the adsorbent

The effect that adsorbent particles may have on the thermodynamic equilibrium of Sorption- Enhanced Reactions (SER) can be determined by means of theoretical models, wherein theoretical results obtained from simulations with or without adsorbent may be directly compared, as shown herein below.

3. 1: Simulation without adsorbent

This example serves to illustrate the theoretical results of a simulation of the reaction of CO2+H2 to produce methanol taking place within a conventional reactor without adsorbent. The operating conditions are taken as T = 225°C, P = 2.5 MPa and a space velocity (GHSV) = 1000 h^-1. By introducing a stoichiometric mixture of CO2 and H2 (i.e. CO2:H2 = 1 :3), a yield of 4.2% to methanol is obtained (Figure 11). To carry out the simulation, a plug flow model has been used with methanol synthesis kinetics taken from Maksimov et al. (Chemical Engineering Journal, 418 (2021) 129290).

3.2: Simulation with adsorbent

This example serves to illustrate the theoretical results of a simulation of a reaction taking place within a reactor with a continuous flow of adsorbent. The operating conditions are taken as T = 250°C, P = 2.5 MPa, a space velocity referred to the catalyst (GHSV) = 1000 h^-1 and a sorbent mass flowrate/ catalyst mass ratio = 1.2 kg/ (kg min). By introducing a stoichiometric mixture of CO2 and H2 (i.e. CO2:H2 = 1 :3), a yield of 20.4% to methanol is obtained (Figure 12). To carry out the simulation, a plug flow model has been taken with a kinetics and absorption equilibrium of Maksimov et al. (2021).

Claims

1. A circulating, fluidized bed, catalytic reactor, wherein the circulating, fluidized bed, catalytic reactor comprises:

2. The circulating, fluidized bed, catalytic reactor according to claim 1 , wherein the plurality of catalyst particles and the plurality of adsorbent particles correspond to Geldart classification types A and/or B.

3. The circulating, fluidized bed, catalytic reactor according to any one of claims 1 or 2, wherein the plurality of catalyst particles and the plurality of adsorbent particles have a particle size in the range 30pm-1 mm, and/or wherein the particle diameter ratio is equal to or higher than 1.5.

4. The circulating, fluidized bed, catalytic reactor according to claim 1 , wherein the plurality of catalyst particles corresponds to Geldart classification type D, and wherein the plurality of adsorbent particles corresponds to Geldart classification types A or B.

5. The circulating, fluidized bed, catalytic reactor according to any one of claims 1 to 4, wherein the plurality of catalyst particles is capable of separating as jetsam and wherein the plurality of adsorbent particles is capable of separating as flotsam.

6. The circulating, fluidized bed, catalytic reactor according to any one of claims 1 to 5, wherein the plurality of catalyst particles is capable of separating as flotsam and wherein the plurality of adsorbent particles is capable of separating as jetsam.

7. The circulating, fluidized bed, catalytic reactor according to any one of claims 1 to 6, wherein the reactor comprises a reactor vessel, and wherein the reaction vessel has different diameters in at least two different sections.

8. The circulating, fluidized bed, catalytic reactor according to any one of claims 1 to 7, wherein the reactor further comprises an inlet stream of an oxidizing agent.

9. A reactor system, wherein the reactor system comprises: a circulating, fluidized bed, catalytic reactor according to any one of claims 1 to 8; and an adsorbent regeneration reactor; wherein the means for recirculating a solid stream of the plurality of adsorbent particles in the circulating, fluidized bed, catalytic reactor are connected to the adsorbent regeneration reactor.

10. The reactor system according to claim 9, wherein the adsorbent regeneration reactor is a fluidized bed reactor or a pneumatic transport reactor.

11 . A method for the continuous, selective regeneration of adsorbent particles in a Sorption Enhanced Reaction (SER), wherein the method comprises: providing a reactor system according to any one of claims 9 or 10; carrying out the SER in the circulating, fluidized bed, catalytic reactor under conditions that separate the plurality of catalyst particles from the plurality of adsorbent particles by means of particle segregation; continuously extracting adsorbent particles using the means for recirculating a solid stream of adsorbent particles in the circulating, fluidized bed, catalytic reactor; regenerating the adsorbent particles in the adsorbent regeneration reactor; returning the regenerated adsorbent particles to the fluidized bed catalytic reactor.

12. Use of the fluidized bed catalytic reactor according to any one of claims 1 to 8, or use of a reactor system according to any one of claims 9 or 10 for carrying out a reaction selected from the group comprising:

Methanol synthesis from CO2, CO, or mixtures of CO2-CO; and hydrogen;

Dimethyl ether production from CO2, CO, or mixtures of CO2-CO; and hydrogen;

Synthesis of synthetic natural gas by CO2 hydrogenation, by CO hydrogenation, or by hydrogenation of mixtures containing CO and CO2;

Fischer-Tropsch hydrocarbon production from syngas;

Hydrogen production from CO + H2O mixtures by water gas shift reaction;

CO production from CO2 + H2 mixtures by reverse water gas shift reaction; Hydrogen production from natural gas or hydrocarbons by steam reforming (CH4 + H₂O CO₂ + 3H₂, CH₄ + 2H₂O CO₂ + 4H₂, C_nH_m + n H₂O n CO₂ + (m/2+n) H2or CnH_m + 2n H2O n CO2 + (m/2+2n) H2); and

13. The use according to claim 12, wherein the reaction is selected from the group consisting of:

Methanol synthesis from CO2, CO, or mixtures of CO2-CO; and hydrogen; - Dimethyl ether production from CO2, CO, or mixtures of CO2-CO; and hydrogen;

Synthesis of synthetic natural gas by CO2 hydrogenation;

Fischer-Tropsch hydrocarbon production from syngas; and

CO production from CO2 + H2 mixtures by reverse water gas shift reaction.