Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/72—Copper
• • B01J35/635—
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
  • B01J21/02—Boron or aluminium; Oxides or hydroxides thereof
  • B01J21/04—Alumina
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
  • B01J21/12—Silica and alumina
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/002—Mixed oxides other than spinels, e.g. perovskite
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/005—Spinels
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/16—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/32—Manganese, technetium or rhenium
  • B01J23/34—Manganese
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/74—Iron group metals
  • B01J23/745—Iron
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/74—Iron group metals
  • B01J23/75—Cobalt
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/74—Iron group metals
  • B01J23/755—Nickel
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/78—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with alkali- or alkaline earth metals
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/83—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with rare earths or actinides
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
  • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
  • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
  • B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
  • B01J23/889—Manganese, technetium or rhenium
  • B01J23/8892—Manganese
• • B01J35/30—
• • B01J35/399—
• • B01J35/40—
• • B01J35/50—
• • B01J35/633—
• • B01J35/638—
• • B01J35/647—
• • B01J35/651—
• • B01J35/653—
• • B01J35/657—
• • B01J35/66—
• • B01J35/69—
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
  • B01J37/0018—Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat)
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
  • B01J37/0027—Powdering
  • B01J37/0045—Drying a slurry, e.g. spray drying
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/02—Impregnation, coating or precipitation
  • B01J37/0201—Impregnation
  • B01J37/0203—Impregnation the impregnation liquid containing organic compounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/02—Impregnation, coating or precipitation
  • B01J37/0201—Impregnation
  • B01J37/0205—Impregnation in several steps
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/02—Impregnation, coating or precipitation
  • B01J37/0201—Impregnation
  • B01J37/0207—Pretreatment of the support
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/02—Impregnation, coating or precipitation
  • B01J37/0236—Drying, e.g. preparing a suspension, adding a soluble salt and drying
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/02—Impregnation, coating or precipitation
  • B01J37/03—Precipitation; Co-precipitation
  • B01J37/038—Precipitation; Co-precipitation to form slurries or suspensions, e.g. a washcoat
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/08—Heat treatment
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
  • F23C10/00—Fluidised bed combustion apparatus
  • F23C10/005—Fluidised bed combustion apparatus comprising two or more beds
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
  • F23C10/00—Fluidised bed combustion apparatus
  • F23C10/01—Fluidised bed combustion apparatus in a fluidised bed of catalytic particles
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
  • F23C10/00—Fluidised bed combustion apparatus
  • F23C10/02—Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed
  • F23C10/04—Fluidised bed combustion apparatus with means specially adapted for achieving or promoting a circulating movement of particles within the bed or for a recirculation of particles entrained from the bed the particles being circulated to a section, e.g. a heat-exchange section or a return duct, at least partially shielded from the combustion zone, before being reintroduced into the combustion zone
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
  • F23C13/00—Apparatus in which combustion takes place in the presence of catalytic material
  • F23C13/08—Apparatus in which combustion takes place in the presence of catalytic material characterised by the catalytic material
• • B01J35/31—
• • B01J35/51—
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/009—Preparation by separation, e.g. by filtration, decantation, screening
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
  • F23C2206/00—Fluidised bed combustion
  • F23C2206/10—Circulating fluidised bed
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E20/00—Combustion technologies with mitigation potential
  • Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

Definitions

• the present invention relates to an oxygen carrier solid, its preparation and its use in an oxidation-reduction process in chemical loop on active mass, commonly known as "Chemical Looping" according to the English terminology.
• the new type of oxygen carrier solid according to the invention can be used in a chemical looping combustion process (Chemical Looping Combustion).
• Chemical mass-based oxidation-reduction processes are known in the field of energy production, gas turbines, boilers and furnaces, particularly for the oil, glass and cement industry.
• the production of electricity, heat, hydrogen or steam can be achieved by this type of process, typically the CLC process, implementing oxidation-reduction reactions of an active mass, called mass oxidation reduction, conventionally a metal oxide, to produce a hot gas from a fuel, for example natural gas, carbon monoxide CO, hydrogen H 2 , coals or petroleum residues, a mixture hydrocarbons, and isolate the carbon dioxide C0 2 produced.
• a fuel for example natural gas, carbon monoxide CO, hydrogen H 2 , coals or petroleum residues, a mixture hydrocarbons, and isolate the carbon dioxide C0 2 produced.
• a fuel for example natural gas, carbon monoxide CO, hydrogen H 2 , coals or petroleum residues, a mixture hydrocarbons, and isolate the carbon dioxide C0 2 produced.
• a fuel for example natural gas, carbon monoxide CO, hydrogen H 2 , coals or petroleum residues, a mixture hydrocarbons, and isolate the carbon dioxide C0 2 produced.
• a second reduction reaction of the oxidized active mass with the aid of a gas, a liquid or a reducing solid (hydrocarbon feedstock) then makes it possible to obtain a reusable active mass and a gaseous mixture comprising essentially CO 2 and water, or even synthesis gas containing CO and H 2 , depending on the conditions operated during the reduction step.
• FIRE I LLE OF REM PLACEM ENT (RULE 26)
• the energy can be produced in the form of steam or electricity for example.
• the heat of combustion of the hydrocarbon feedstock is similar to that encountered in conventional combustion. This corresponds to the sum of the heats of reduction and oxidation in the chemical loop.
• the heat is generally extracted by exchangers located inside, wall or appendage of the fuel and / or air reactors, on the flue lines, or on the transfer lines of the active mass.
• a major advantage of these oxidation-reduction processes in chemical loop on active mass is then to allow to easily isolate the CO 2 (or synthesis gas) contained in the gaseous mixture without oxygen and nitrogen constituting the effluent from the reduction reactor.
• Another advantage is the production of a flow of nitrogen N 2 (and argon) containing almost no oxygen, and corresponding to the effluent from the oxidation reactor, when the air is used as oxidizing gas.
• the CLC process thus provides an attractive solution for C0 2 capture with a view to its sequestration or recovery for other processes, in order to limit the emission of greenhouse gases. greenhouse that is detrimental to the environment.
• US Pat. No. 5,447,024 for example describes a CLC process comprising a first reactor for reducing an active mass using a reducing gas and a second oxidation reactor for restoring the active mass in its oxidized state by an oxidation reaction with moist air.
• the circulating fluidized bed technology is used to allow the continuous passage of the active mass of the reduction reactor to the oxidation reactor and vice versa.
• Patent application WO 2006/123925 describes another implementation of the CLC process using one or more fixed-bed reactors containing the active mass, the redox rings being carried out by permutation of the gases in order to successively carry out the oxidation and reduction of the active mass.
• the active mass passing alternately from its oxidized form to its reduced form and vice versa, describes an oxidation-reduction cycle.
• the terms oxidation and reduction are used in relation to the respectively oxidized or reduced state of the active mass.
• the oxidation reactor is one in which the active mass is oxidized and the reduction reactor is the reactor in which the active mass is reduced.
• the active mass usually a metal oxide (M x O y)
• M x O y metal oxide
• C n H m hydrocarbon
• CO + H 2 optionally in mixture CO + H 2 according to the nature of the active mass and the proportions used.
• M x O y-2n -m / 2 + (2n + m / 2) H 2 0 - »M x O y + (2n + m / 2) H 2 (3)
• M represents a metal
• the active mass acts as an oxygen carrier in the chemical loop redox process.
• solid carrying oxygen the solid comprising the active mass, typically comprising the metal oxide or oxides capable of exchanging oxygen under the redox conditions of the oxidation-reduction process in a chemical loop.
• the oxygen carrier solid may further comprise a binder or a support in association with the active mass, in particular to ensure good reversibility of oxidation and reduction reactions, and improve the mechanical strength of the particles.
• the active masses chosen, for example, from the redox couples of copper, nickel, iron, manganese and / or cobalt, are generally not used in pure form since the successive oxidation / reduction cycles at high temperature lead to a significant and rapid decrease in the oxygen transfer capacity, due to the sintering of the particles.
• the oxygen-carrying solid comprises a NiO / Ni redox couple as an active mass, associated with a YSZ binder which is yttrium stabilized zirconia, also called yttria zirconia.
• a YSZ binder which is yttrium stabilized zirconia, also called yttria zirconia.
• Many types of binders and supports, in addition to yttria YSZ zirconia, have been studied in the literature to increase the mechanical strength of particles at a lower cost than YSZ.
• the effectiveness of the oxidation-reduction process in a chemical loop depends mainly on the physicochemical properties of the oxygen-carrying solid.
• the lifetime of the particles in the process has a preponderant impact on the operating cost of the process, particularly in the case of circulating fluidized bed process.
• the attrition rate of the particles makes it necessary to compensate for the loss of oxygen-carrying solid in the form of fines, typically particles of the oxygen-carrying solid with a diameter of less than 40. ⁇ , with new oxygen carrier solid.
• the rate of renewal of the oxygen-carrying solid therefore strongly depends on the mechanical strength of the particles as well as their chemical stability under the process conditions, which includes many successive oxidation / reduction cycles.
• the porosity of ilmenite ore particles increases strongly with redox cycles and results in their sputtering, potentially challenging the adequacy of this ore to the process, while early studies on the use of ilmenite concluded at its conclusion. good suitability for the CLC process.
• the increase in porosity observed by the minute characterization of the particles after the test is concomitant with the migration of ferrous and / or ferric ions by diffusion within the particles. According to the authors, segregation of iron within the particles precedes its migration to the surface, creating the porosity that results in the disaggregation of the particles in the form of fines.
• the appearance of porosity is the main mechanism for the formation of fine particles during the process, considerably limiting the lifetime of the particles, and therefore the potential value of the ore for the CLC application. Indeed, the estimated lifespan of ilmenite particles is of the order of only 200 hours ("Emerging C0 2 Capture Systems", JC Abanades, B. Arias, A. Lyngfelt, T. Mattisson, DE Wiley, H Li, MT Ho, E. Mangano, S. Brandani, J. Int Greenhouse Gas Control 40 (2015), 126).
• the attrition phenomenon of the oxygen-carrying solid is thus mainly due to a morphological evolution linked to the consecutive redox cycles experienced by the particles rather than to shocks on the walls and between particles, usually considered as the main source of attrition in fluidized bed processes.
• the patent application WO 2012/155059 discloses the use of oxygen carrier solids consisting of an active mass (20 to 70% by weight), a primary support material of the ceramic or clay type (5 to 70% by weight). , and a secondary support material (1 to 35% by weight), also of ceramic or clay type.
• An improved mechanical stability related to the control of the volume expansion is advanced for these solid oxygen carriers. It is explained that a diffusion movement of the iron ions towards the outside of the particles causes the volume expansion of the particles, which leads to embrittlement of the particles.
• the primary support material would make it possible to disperse the metallic active mass and prevent its agglomeration, preserving the redox activity, whereas the secondary support material would serve to reduce the speed of volume expansion by forming a phase stabilizing solid that would prevent iron migration to the surface.
• Lyngfelt et al. performed a 1000h test with nickel-based particles (40% NiO / 60% NiAl 2 O 4 ) in a 10kWth circulating fluidized bed plant (Linderholm, C., Mattisson, T. & Lyngfelt, A., "Long-term integrity testing of spray-dried particles in a 10-kW chemical-looping combustor using natural gas as fuel", Fuel, 88 (1 1), (2009) 2083-2096).
• the authors conclude that the lifetime of the particles is of the order of 33000h, but a fairly high proportion of agglomerates is observed at the end of the test and part of the solid adhered to the walls of the reactor.
• the present invention aims to overcome the problems of the prior art described above, and generally aims to provide an oxygen carrier solid for a chemical loop oxidation reduction process which has a long service life when of his use in the process, in particular to reduce investment costs and / or operation for such processes.
• the present invention provides, in a first aspect, a particulate oxygen carrier solid for a method of combustion of a hydrocarbon feedstock by oxido. - chemical loop reduction, comprising:
• an oxidation-reduction active mass constituting between 5% and 75% by weight of said oxygen-carrying solid, said oxidation-reduction active mass comprising a metal oxide or a mixture of metal oxides and being capable of transporting oxygen in the oxidation-reduction process in a chemical loop;
• a ceramic matrix in which is dispersed said oxidation-reduction active mass, said ceramic matrix constituting between 25% and 95% by weight of said oxygen-carrying solid, and said ceramic matrix comprising 100% by weight of at least one oxide having a melting temperature above 1500 ° C;
• the total pore volume of the oxygen-carrying solid measured by mercury porosimetry, is between 0.05 and 1.2 ml / g
• the pore volume of the macropores constitutes at least 10% of the total pore volume of the oxygen-carrying solid
• the size distribution of the macropores within the oxygen carrier solid, measured by mercury porosimetry, is between 50 nm and 7 ⁇ .
• the total pore volume of the oxygen-carrying solid is between 0.1 and 0.85 ml / g.
• the porous volume of the macropores advantageously constitutes at least 10% of the total pore volume of the oxygen-carrying solid.
• the size distribution of the macropores in the oxygen-carrying solid is between 50 nm and 3 ⁇ .
• the active oxidation-reduction mass comprises at least one metal oxide included in the list consisting of the oxides of Fe, Cu, Ni, Mn and Co, a perovskite having redox properties, preferably a perovskite of formula CaMnO 3 , a metal aluminate spinel having redox properties, preferably a metal aluminate spinel of formula CuAl 2 O 4 or a Cuprospinelle of formula CuFe 2 O 4 .
• the oxidation-reduction active mass comprises at least one copper oxide.
• said at least one oxide of the ceramic matrix has a melting temperature greater than 1700 ° C., and preferably greater than 2000 ° C.
• Said at least one oxide of the ceramic matrix may be chosen from the list consisting of calcium aluminate of formula CaAl 2 O 4 , silica of formula SiO 2 , titanium dioxide of formula TiO 2 , perovskite of formula CaTiO 3 , alumina of formula Al 2 O 3 , zirconia of formula ZrO 2 , yttrium dioxide of formula Y 2 O 3 , barium zirconate of formula BaZrO 3 , magnesium aluminate of formula MgAl 2 0 4 , magnesium silicate of formula MgSi 2 O 4 , lanthanum oxide of formula La 2 0 3 .
• said at least one oxide of the ceramic matrix is silica, alumina, or a mixture of alumina and silica, and preferably is alumina.
• the particles have a particle size such that more than 90% of the particles have a size of between 50 ⁇ and 600 ⁇ .
• the invention relates to a process for preparing an oxygen-carrying solid according to one of Claims 1 to 11, comprising the following steps:
• step (B) spray-drying said slurry obtained in step (A) to form particles, said spray drying comprising spraying the slurry in a drying chamber using spray means to form droplets and simultaneously contacting said droplets with a hot carrier gas, preferably air or nitrogen, brought to a temperature of between 200 ° C and 350 ° C;
• a hot carrier gas preferably air or nitrogen
• step (C) calcining the particles resulting from the spray drying in step (B), said calcination being carried out under air and at a temperature between 400 ° C and 1400 ° C;
• step (D) the optional screening of the calcined particles from step (C), by separation by means of a cyclone;
• step (C) (i) impregnating the particles from step (C) with a precursor compound of an oxidation-reduction active mass, and (ii) drying the impregnated particles followed by (iii) calcination;
• step (A) incorporation of the active-oxydo-reducing mass during the preparation of the suspension in step (A).
• step e1) comprises:
• step (i) impregnating the particles resulting from step (C) with an aqueous or organic solution containing at least one soluble precursor compound of copper, nickel, cobalt, iron or manganese, preferably with an aqueous solution containing at least one precursor compound of the oxidation-reduction active mass selected from the list consisting of nitrates of the following formulas: Cu (N0 3 ) 2 .xH 2 O, Ni (N0 3 ) 2 .xH 2 O, Co (N0 3 ) 2 .xH 2 O, Fe (NO 3 ) 3 .xH 2 O, Mn (NO 3 ) 2 ⁇ xH 2 0.
• the impregnation (i) in step e1) is carried out in one or more successive stages, and preferably comprises intermediate stages of drying at a temperature between 30 ° C and 200 ° C and / or calcination at a temperature between 200 ° C and 600 ° C when the impregnation is performed in several successive steps.
• drying (ii) in step e1) is carried out under air or in a controlled atmosphere, at a temperature between 30 ° C and 200 ° C, and preferably in air at a temperature between 100 ° C and 150 ° C.
• the calcination (iii) in step e1) is carried out under air at a calcining temperature of between 450 ° C. and 1400 ° C., preferably between 600 ° C. and 1000 ° C., more preferably between 700 ° C and 900 ° C, and is carried out for a period of 1 to 24 hours, and preferably for a period of 5 to 15 hours.
• step e2) comprises (j) impregnating the grains of said precursor oxide (s) with the ceramic matrix with an aqueous or organic solution containing at least one soluble precursor compound of copper, nickel, cobalt , iron or manganese, preferably with an aqueous solution containing at least one precursor compound of the oxidation-reduction active mass selected from the list consisting of nitrates of the following formulas: Cu (NO 3 ) 2 .xH 2 0 , Ni (NO 3 ) 2 .xH 2 O, Co (NO 3 ) 2 .xH 2 O, Fe (NO 3 ) 3 .xH 2 O, Mn (NO 3 ) 2 .xH 2 0, said impregnation being carried out before suspending said grains.
• step e2) may comprise (jj) the addition of at least one precursor of the active redox active mass, said precursor being a soluble compound of copper, nickel, cobalt, iron and / or or manganese to the suspension prepared in step (A), and preferably a precursor compound of the oxidation-reduction active mass selected from the list consisting of nitrates of the following formulas: Cu (N0 3 ) 2 .xH 2 0, Ni (N0 3) 2 .xH 2 0, Co (N0 3) 2 .xH 2 0, Fe (N0 3) 3 .xH 2 0, Mn (N0 3) 2 .xH 2 0.
• step e2) may comprise (jjj) the addition to the suspension prepared in step (A) of grains of at least one metal oxide included in the list consisting of oxides of Fe, Cu, Ni, Mn and Co, a perovskite having redox properties, preferably a perovskite of formula CaMnO 3 , a metal aluminate spinel having redox properties, preferably a metal aluminate spinel of formula CuAl 2 O 4 or of formula CuFe 2 0 4 , said grains having a size between 0, 1 ⁇ and 20 ⁇ , preferably between 0.5 ⁇ and 5 ⁇ , and more preferably between 1 ⁇ and 3 ⁇ , to form the active mass of oxido. reduction of the oxygen carrier solid.
• step A) is added to the aqueous suspension at least one binder intended to enhance the cohesion of the particles obtained at the end of step (B), and / or control rheology of said suspension aqueous
• said binder being an organic binder, preferably selected from the list consisting of polyethylene glycol, polyvinyl alcohol, polyacrylate, polyvinylpyrrolidone, or an inorganic binder, preferably selected from the list consisting of aluminum hydroxides, boehmite, diaspore, tetraethylorthosilicate, silicic acid, aluminosilicates and kaolin-type clays.
• step A) is added to the aqueous suspension at least one pore-forming agent for increasing the macroporosity of the particles of the oxygen-bearing solid.
• step E) fines of the oxygen-carrying solid produced during the use of said oxygen-bearing solid are recycled in a process for combustion of a hydrocarbon feedstock by oxidation-reduction by chemical loop.
• the invention relates to a method of combustion of a hydrocarbon feedstock by oxido-reduction in a chemical loop using an oxygen carrier solid according to the invention or prepared according to the preparation method according to the invention.
• the invention relates to a CLC process, preferably in which the oxygen carrier solid circulates between at least one reduction zone and a zone both operating in a fluidized bed, the temperature in the reduction zone and in the oxidation zone being between 400 ° C. and 1400 ° C., preferably between 600 ° C. and 1100 ° C., and more preferably between 800 ° C and 1100 ° C.
• FIGS. 1A, 1B, 1C and 1D relate to an oxygen carrier solid according to Example 2 (example not in accordance with the invention).
• FIG. 1A is a diagram giving information on the porosity of the oxygen carrier solid.
• Fig. 1B is a diagram showing the conversion of methane as a function of oxidation-reduction cycles in a CLC process using the oxygen-carrying solid.
• Fig. 1C is a diagram showing the particle size distribution of the oxygen carrier solid before and after its use in a CLC process.
• Figure 1D is a scanning electron microscope (SEM) photograph of a polished section of a sample of the oxygen-carrying solid after its use in a CLC process.
• SEM scanning electron microscope
• FIGS. 2A, 2B, 2C and 2D relate to an oxygen carrier solid according to Example 3 (example not in accordance with the invention).
• Fig. 2A is a diagram giving information on the porosity of the oxygen carrier solid.
• Figure 2B is a diagram showing the conversion of methane versus oxidation-reduction cycles in a CLC process using the oxygen-carrying solid.
• FIG. 2C shows in (a) a SEM image and (b) an energy dispersive X-ray spectrometry (EDX) mapping of the oxygen-carrying solid prior to its use in a CLC process.
• Figure 2D is an SEM view of a polished section of a sample of the oxygen-carrying solid after its use in a CLC process.
• EDX energy dispersive X-ray spectrometry
• FIGS. 3A, 3B, 3C, 3D and 3E relate to an oxygen carrier solid according to Example 4 (example according to the invention).
• Fig. 3A is a diagram giving information on the porosity of the oxygen carrier solid before use in a CLC process.
• Figure 3B is a SEM backscattered electron sample on the polished section of the oxygen carrier solid prior to its use in a CLC process.
• Figure 3C is a diagram showing the conversion of methane versus oxidation-reduction cycles in a CLC process using the oxygen-carrying solid.
• Figure 3D is a diagram providing information on the porosity of the oxygen carrier solid after use in a CLC process.
• Figure 3E shows in (a) and (b) two SEM images of a polished section of a sample of the oxygen-carrying solid after its use in a CLC process.
• FIGS. 4A, 4B, 4C, 4D and 4E relate to an oxygen carrier solid according to Example 4 (example according to the invention).
• Fig. 4A is a diagram giving information on the porosity of the oxygen carrier solid before use in a CLC process.
• Figure 4B is a SEM backscattered electron sample on the polished section of the oxygen-carrying solid prior to its use in a CLC process.
• Fig. 4C is a diagram showing the conversion of methane as a function of oxidation-reduction cycles in a CLC process using the oxygen carrier solid.
• Fig. 4D is a diagram giving information on the porosity of the oxygen carrier solid after use in a CLC process.
• Figure 4E shows a SEM backscattered electron micrograph of a polished section of a sample of the oxygen-bearing solid after its use in a CLC process.
• the object of the invention is to propose an oxygen-carrying solid for a chemical loop-redox process, such as a CLC process, but also for other chemical loop-redox processes.
• active mass such as a chemical loop reforming process (CLR with reference to the term “Chemical Looping Reforming") or a method of CLOU (with reference to the phrase “Chemical Looping Oxygen Uncoupling”).
• the present invention also relates to the preparation and use of the oxygen-carrying solid in such processes.
• the CLC processes generally use two separate reactors to perform on the one hand in a reduction reactor, the reduction of the active mass by means of a fuel, or more generally a gas, liquid or reducing solid.
• the effluents from the reduction reactor mainly contain CO 2 and water, allowing easy capture of CO 2 .
• the oxidation reactor the restoration of the active mass to its oxidized state by contact with air or any other oxidizing gas makes it possible to correlatively generate a hot energy vector effluent and a nitrogen stream. poor or free of nitrogen (where air is used).
• the carrier solid Oxygen according to the invention can also be used in any other type of oxidation-reduction process in a chemical loop (CLC, CLR, CLOU) in a fixed, mobile or bubbling bed, or in a rotating reactor.
• the oxygen carrier comprises:
• an oxidation-reduction active mass constituting between 5% and 75% by weight of the oxygen-carrying solid, preferably between 10% and 40% by weight, the oxidation-reduction active mass comprising a metal oxide or a mixture metal oxides and being capable of exchanging oxygen under the redox conditions of said chemical loop-redox process;
• a ceramic matrix in which the oxidation-reduction active mass is dispersed the ceramic matrix constituting between 25% and 95% by weight of the oxygen-carrying solid, preferably between 60% and 90% by weight, and the ceramic matrix comprising 100% by weight of at least one oxide having a melting temperature of greater than 1500 ° C., and preferably having a melting point of greater than 1700 ° C., and even more preferably having a melting point greater than 2000 ° C.
• a ceramic matrix comprising 100% by weight of at least one oxide, it is meant that the matrix consists essentially of this oxide (or mixture of oxides), at 1% by weight.
• oxygen has a particular porosity which, unexpectedly, makes it possible to limit the migration phenomenon of the active mass within the oxygen carrier particles.
• This initial texture significantly improves the lifetime of the particles in the chemical loop combustion process and is characterized in that:
• the total pore volume of the Vtot oxygen-carrying solid measured by mercury porosimetry, is between 0.05 and 1.2 ml / g; -
• the total pore volume Vtot ûu solid oxygen carrier comprises at least 10% of macropores.
• the pore volume of the macropores constitutes at least 10% of the total pore volume Vtot ûu solid carrying oxygen;
• the size distribution of the macropores within the oxygen carrier solid, measured by mercury porosimetry, is between 50 nm and 7 ⁇ .
• initial texture is meant the texture before any use in a chemical loop redox process such as CLC.
• the total pore volume of the solid is measured by mercury porosimetry, more precisely the measurement relates to the volume of mercury injected when the pressure exerted increases from 0.22 MPa to 413 MPa.
• the total pore volume of the solid oxygen carrier is preferably from 0.1 to 0.85 ml / g.
• the total pore volume Vtot of the particles is constituted for at least 40% by macropores.
• the pore volume of the macropores constitutes at least 40% of the total pore volume Vtot ûu solid oxygen carrier.
• the remainder of the total pore volume may be indifferently constituted by microporosity or mesoporosity in any proportion whatsoever.
• the size distribution of the macropores within the particles is more preferably between 50 nm and 3 ⁇ , and even more preferably between 200 nm and 1 ⁇ .
• Grzesik "Oxidation of nickel and transport properties of nickel oxide.” J.Phys.Chem.Solids, 64, 1651, 2004), because the diffusion rate of metal cations in the The oxide is higher than that of the oxygen anion (O 2 ).
• the ceramic matrix consists essentially of at least one oxide, or a mixture of oxides, having a melting point greater than 1500 ° C., preferably greater than 1700 ° C. and more preferably greater than 2000 ° C., which is preferably selected from the list consisting of calcium aluminate CaAl 2 0 4, silica Si0 2, titanium dioxide Ti0 2, CaTi0 3 perovskite, alumina Al 2 0 3, zirconia Zr0 2, the dioxide yttrium Y 2 O 3 , barium zirconate BaZrO 3 , magnesium aluminate MgAl 2 O 4 , magnesium silicate MgSi 2 O 4 , lanthanum oxide La 2 O 3 .
• Calcium aluminate CaAl 2 O 4 has a melting temperature greater than 1500 ° C.
• silica SiO 2 titanium dioxide TiO 2 and perovskite CaTiO 3 have a melting point greater than 1700 ° C.
• magnesium aluminate MgAl 2 0 4 magnesium silicate MgSi 2 0 4, and lanthanum oxide
• La 2 0 3 has a melting temperature higher than 2000 ° C.
• said oxide of the ceramic matrix is silica, alumina, or a mixture of alumina and silica.
• oxide covers a mixed oxide, that is to say a solid resulting from the combination of oxide ions O 2 " with at least two cationic elements (for example calcium aluminate CaAl 2 0 4 or magnesium aluminate MgAl 2 0 4 )
• mixing oxides is meant at least two distinct solid compounds each being an oxide.
• the oxide or oxides of the ceramic matrix having a high melting temperature, greater than 1500 ° C., their use is advantageous in the context of chemical loop-redox processes such as CLC where the temperature reached by the particles of the Oxygen carrier is higher than that of the fluidizing gas, sometimes up to 120 ° C (Guo, XY; Sun, YL; Li, R; Yang, F .; Experimental investigations on temperature variation and inhomogeneity in a packed CLC reactor of large particles and low aspect ratio. "Chem.Eng.Sci., 107, 266, 2014). The higher the melting temperature of the oxide or oxide mixture constituting the ceramic matrix, the more said ceramic matrix is resistant to sintering.
• Table 1 below lists the examples of oxides that can make up the ceramic matrix of the oxygen-carrying solid, and indicates their fusion temperature "T fusion", Huttig (T H ) and Tammann (T T ),
• the ceramic matrix can be obtained from the treatment of solid particles obtained by a spray drying technique of an aqueous suspension of oxide (s) of specific size.
• the oxygen-carrying solid is obtained by integrating the oxido-reducing active mass into the ceramic matrix, that is to say from the stage of formation of the aqueous suspension.
• precursor oxide (s) of the ceramic is subsequently impregnated with particles of the ceramic matrix.
• the oxygen-carrying solid according to the invention comprises an oxidation-reduction active mass which comprises, and preferably consists of, at least one metal oxide included in the list consisting of Fe, Cu, Ni and Mn oxides. and Co, a perovskite having redox properties, preferably a perovskite of the formula CaMnO 3 , a metal aluminate spinel having redox properties, for example a metal aluminate spinel of formula CuAl 2 O 4 or of formula CuFe 2 4 .
• the spinel of formula CuFe 2 O 4 is a cuprospinelle.
• the oxidation-reduction active mass comprises at least one copper oxide, preferably of formula CuO, and is more preferably constituted by at least one copper oxide, preferably of formula CuO.
• the oxygen carrier solid advantageously has an active mass dispersed within the ceramic matrix, typically an initial distribution of the relatively homogeneous initial active mass, and the migration of the active mass within the particles of the solid carrier.
• Oxygen is minimized during the redox cycles of the chemical loop redox process, as illustrated by some examples later in the description.
• the oxido-reducing active mass is capable of exchanging oxygen under the redox conditions of the chemical loop redox process.
• the active mass is reduced according to the reaction (1) already described above, during a reduction step in contact with a hydrocarbon feedstock, and is oxidized according to reaction (2) or (3) already described above, when an oxidation step in contact with an oxidizing gas.
• the oxygen storage capacity of the oxido-reducing active mass is advantageously, depending on the type of material, between 1% and 15% by weight.
• the amount of oxygen effectively transferred by the metal oxide is between 1 and 3% by weight, which makes it possible to use only a fraction of the oxygen transfer capacity.
• the oxygen carrier solid according to the invention is preferably in the form of particles, which can be fluidized in the oxidation-reduction process in a chemical loop, in particular be implemented in a circulating fluidized bed.
• They may be fluidizable particles (fluidizable powder, generally called “fluidisable carrier” in English) belonging to groups A, B or C of the Geldart classification (D. Geldart, "Types of gas fluidization", Powder Technol. (5), 285-292, 1973), and preferably the particles belong to group A or group B of the Geldart classification, and preferably to group B of the Geldart classification.
• the particles of the oxygen-carrying solid have a particle size such that more than 90% of the particles have a size of between 50 ⁇ and 600 ⁇ , more preferably a particle size such that more than 90% of the particles have a size of between 80 ⁇ and 400 ⁇ , more preferably a particle size such that more than 90% of the particles have a size of between 100 ⁇ and 300 ⁇ , and even more preferably a particle size such that more than 95% of the particles have a size between 100 ⁇ and 300 ⁇ .
• the particles of the oxygen-carrying solid have a grain density of between 500 kg / m 3 and 5000 kg / m 3 , preferably a grain density of between 800 kg / m 3 and 4000 kg / m 3 , and even more preferably a grain density of between 1000 kg / m 3 and 3000 kg / m 3 .
• the particles of the oxygen-bearing solid are preferably substantially spherical.
• the size distribution and morphology of the particles for use in another type of chemical loop process (CLC, CLR, CLOU) fixed bed, moving bed or rotating reactor are adapted to the process envisaged.
• the preferred size of the particles is greater than 400 ⁇ , in order to minimize the pressure losses.
• the morphology of the particles is not necessarily spherical.
• the morphology is dependent on the shaping mode, for example in the form of extrudates, beads, monoliths or particles of any geometry obtained by grinding larger particles.
• the solid carrier of oxygen, in the form of particles is deposited on the surface of the ceramic monolith channels by the coating methods known to those skilled in the art, or the monolith itself consists of the particles according to the invention.
• Particle size can be measured by laser particle size.
• the size distribution of the particles of the oxygen-carrying solid is preferably measured using a laser particle size analyzer, for example Malvern Mastersizer 3000, preferably in liquid form, and using the Fraunhofer theory. Such a technique and such material can also be used to measure the size of other grains such as precursor oxide grains of the ceramic matrix.
• Obtaining particles from the oxygen carrier in the desired size range requires a shaping step from grains of smaller size, the size of which is between 0.1 and 20 ⁇ , preferably between 0.5. and 5 ⁇ , and more preferably between 1 and 3 ⁇ .
• the shaping can be carried out according to all the techniques known to those skilled in the art for obtaining particles, such as extrusion, compaction, wet or dry granulation ("wet or dry granulation").
• a sieving and / or screening step (classification or separation for example by means of a cyclone) can be further carried out in order to select the particles of the desired particle size.
• the oxygen carrier solid may be prepared according to a process comprising the following steps:
• Step (A) comprises the preparation of an aqueous suspension of oxide or a mixture of oxides, said solution having suitable rheological characteristics for pumping and spraying.
• the oxide or oxides form grains whose size is between 0.1 ⁇ m and 20 ⁇ m, preferably between 0.5 ⁇ m and 5 ⁇ m, and more preferably between 1 ⁇ m and 3 ⁇ m.
• the oxide or the mixture of oxides are the precursors of the ceramic matrix of the oxygen-bearing solid and have a melting temperature greater than 1500 ° C., preferably greater than 1700 ° C., and even more preferably greater than 2000 ° C. vs.
• These components are preferably chosen from the list consisting of calcium aluminate of formula CaAl 2 O 4 , silica of formula SiO 2 , titanium dioxide of formula TiO 2 , perovskite of formula CaTiO 3 , alumina of formula Al 2 O 3 , zirconia of formula ZrO 2 , yttrium dioxide of formula Y 2 O 3 , barium zirconate of formula BaZrO 3 , magnesium aluminate of formula MgAl 2 O 4 , magnesium silicate of formula MgSi 2 O 4 , lanthanum oxide of formula La 2 0 3 .
• One or more organic and / or inorganic binders may be added to the suspension to adjust and control the rheology of the suspension and to ensure the cohesion of the particles which are obtained at the end of the suspension. shaping step, prior to consolidation by calcination in a subsequent step.
• the organic binding agent (s) of variable molecular weight may be chosen from polyethylene glycol (PEG), polyvinyl alcohol (PVA), polyacrylate (PA), polyvinylpyrrolidone (PVP) and the like. They can be added at a level of 0.5% to 6% by weight relative to the mass of oxide (s) in suspension.
• PEG polyethylene glycol
• PVA polyvinyl alcohol
• PA polyacrylate
• PVP polyvinylpyrrolidone
• the inorganic binder (s) may be chosen from aluminum hydroxides (bayerite, gibbsite, nordstrandite), boehmite, diaspore, tetraethylorthosilicate, silicic acid, kaolin type aluminosilicates and clays, and the like. They can be added at a level of 5% to 30% by weight relative to the mass of oxide (s) in suspension.
• One or more blowing agents for increasing the macroporosity of the particles may also be added to the suspension.
• agents are typically organic compounds that can be burned, such as starch, cellulose, polymers such as polypropylene, latex, poly (methyl methacrylate) (PMMA).
• the suspension obtained in step (A) is spray-dried: the suspension is sprayed into fine droplets in a drying chamber by means of spraying means, for example using a pneumatic (bi-fluid) or hydraulic (monofluid) spray nozzle, and these droplets are simultaneously brought into simultaneous contact with a hot carrier gas, preferably air or nitrogen, brought to a temperature of between 200 and 350 ° C.
• a hot carrier gas preferably air or nitrogen, brought to a temperature of between 200 and 350 ° C.
• the hot carrier gas is introduced with a co-current flow (ceiling mode) or a mixed flow (fountain mode) allowing the evaporation of the solvent and obtaining spherical particles to the desired particle size.
• This step advantageously allows the formation of particles of desired particle size.
• this step is carried out so as to produce particles having the following particle size: more than 90% of the particles have a size of between 50 and ⁇ , preferably more than 90% of the particles have a size of between 80 ⁇ and 400. ⁇ , more preferably more than 90% of the particles have a size between 100 ⁇ and 300 ⁇ , and even more preferably more than 95% of the particles have a size between 100 ⁇ and 300 ⁇ .
• An optional subsequent screening step (D) can be performed to obtain the desired particle size, described below.
• the particles resulting from the spray drying in step (B) are calcined under air at a temperature between 400 ° C. and 1400 ° C., preferably between 600 ° C. and 1200 ° C., and very preferably between 650 and 900 ° C. ° C. This calcination step has an impact on the mechanical strength of the particles.
• step e2) j) described below it is possible to carry out a ramp for increasing the temperature between 1 ° C./min and 50 ° C./min, and preferably between 5 ° C./min and 20 ° C./min, to reach the given calcination temperature, in particular when the integration of the oxidation-reduction active mass with the oxygen-carrying solid is carried out according to step e2) j) described below (prior impregnation with the precursor of the active mass of the oxide grains which are suspended in step (A)).
• a screening can be performed at the end of the calcination step (C) to select the particles in a range of desired size.
• the screening may be carried out by particle separation by means of a cyclone, or any other means of separation.
• Step (E) comprises either step e1) or step e2).
• Step (E) makes it possible to associate the oxido-reducing active mass with the ceramic matrix in order to produce the particle-carrying solid oxygen in the form of particles according to the invention.
• the calcined particles obtained at the end of step (C), and optionally screened at the end of step (D), are (i) impregnated with an aqueous or organic solution containing at least minus a soluble precursor compound of copper, nickel, cobalt, iron or manganese.
• the impregnation is carried out with an aqueous solution containing at least one precursor compound of the oxidation-reduction active mass selected from the list consisting of the nitrates of the following formulas: Cu (N0 3 ) 2 ⁇ xH 2 0, Ni (N0 3 ) 2 .xH 2 O, Co (NO 3 ) 2 .xH 2 O, Fe (NO 3 ) 3 .xH 2 O, Mn (NO 3 ) 2 ⁇ xH 2 0.
• the nitrates of the following formulas: Cu (N0 3 ) 2 ⁇ xH 2 0, Ni (N0 3 ) 2 .xH 2 O, Co (NO 3 ) 2 .xH 2 O, Fe (NO 3 ) 3 .xH 2 O, Mn (NO 3 ) 2 ⁇ xH 2 0.
• the copper nitrate Cu (NO 3 ) 2 .xH 2 O is chosen to carry out this impregnation, in order to obtain an oxido-reducing active mass of copper oxide (s), for example a copper oxide of formula CuO, to form the oxygen carrier solid.
• the amount of precursor of the oxidation-reduction active mass used for the impregnation stage is chosen so that the active redox mass constitutes between 5% and 75% by weight of the solid carrier substance.
• oxygen preferably constitutes between 10% and 40% by weight of the oxygen-carrying solid.
• the impregnation can be carried out in one or more successive stages.
• impregnation is carried out in several successive stages, intermediate stages of drying at a temperature of between 30 ° C. and 200 ° C. and / or calcination at a temperature of between 200 ° C. and 600 ° C. are preferably carried out.
• the impregnated particles are then (ii) dried, for example in the oven, and preferably under air or in a controlled atmosphere (controlled relative humidity, under nitrogen).
• controlled atmosphere is meant for example with a controlled relative humidity or under nitrogen. This drying is carried out at a temperature between 30 ° C and 200 ° C.
• step (C) results in the solid carrier of oxygen in the form of particles according to the invention.
• This calcination (iii) is preferably carried out under air between 450 ° C. and 1400 ° C., more preferably between 600 ° C. and 1000 ° C., and even more preferably between 700 ° C. and 900 ° C.
• This calcination can be carried out for a period of 1 to 24 hours, and preferably for a period of 5 to 15 hours.
• a ramp for increasing the temperature between 1 ° C./min and 50 ° C./min, and preferably between 5 ° C./min and 20 ° C./min, is applied to reach the given calcination temperature.
• the time to implement this temperature ramp is not included in the calcination time ranges indicated above.
• This calcination allows the formation of the oxidoreductive active mass dispersed within the ceramic matrix.
• this calcination step (iii) has a limited impact on the initial macroporous structure of the particles, and all the more limited when the calcination is carried out at a temperature between 700 ° C and 900 ° C. A small increase in macropore diameter and a small decrease in total pore volume can be observed.
• step e2) and alternatively to what is done in step e1), the redox active mass is associated with the ceramic matrix during the preparation of the suspension in step (A) .
• Said precursor compound of the active mass, soluble in water may be chosen from the list consisting of nitrates of the following formulas: Cu (N0 3 ) 2 .xH 2 0, Ni (N0 3 ) 2 .xH 2 0, Co (NO 3 ) 2 .xH 2 O, Fe (NO 3 ) 3 .xH 2 O, Mn (NO 3 ) 2 .xH 2 O.
• the impregnation is carried out before suspending the grains.
• a soluble precursor of copper and preferably copper nitrate Cu (N0 3 ) 2.xH 2 0, is chosen to carry out this impregnation, in order to obtain an oxido-reducing active mass of copper oxide (s), for example a copper oxide of formula CuO, to form the solid carrier of oxygen.
• a drying step followed by a calcination step, as described in step e1) (ii) and (iii) can be carried out as a result of this impregnation (j).
• the soluble compound is chosen from the list consisting of nitrates of the following formulas: Cu (N0 3 ) 2 ⁇ xH 2 0, Ni (N0 3 ) 2 ⁇ xH 2 0, Co (N0 3 ) 2 ⁇ xH 2 0 , Fe (NO 3 ) 3 .xH 2 O, Mn (NO 3 ) 2 .xH 2 0.
• the precursor chosen is a soluble compound of copper, more preferably copper nitrate Cu (NO 3 ) 2 . xH 2 0.
• (jjj) adding to the suspension prepared in step (A) at least one oxide of copper, nickel, cobalt, iron, manganese, a perovskite having redox properties (for example CaMnO 3 ), a metal aluminate spinel having redox properties (for example CuFe 2 O 4 , CuAl 2 O 4 ), or any other compound capable of exchanging oxygen under the redox conditions of the chemical loop-redox process such as than the CLC.
• These precursors of the active mass added to the suspension prepared in step (A) are solids in the form of grains, of size between 0.1 ⁇ and 20 ⁇ , preferably between 0.5 ⁇ and 5 ⁇ . , and more preferably between 1 ⁇ and 3 ⁇ .
• a copper oxide is added to the suspension prepared in step (A).
• the preparation of the oxygen-carrying solid according to the invention can comprise the recycling in step E) of the oxygen carrier fines produced during its use in a chemical loop-redox process such as CLC. for example by addition during step (d) in the suspension prepared in step (A) of less than 10% by weight of fines with respect to the total oxide content (s) of the suspension.
• the recycled fines consist of a mixture of the active mass and the ceramic matrix, whose size is less than 40 ⁇ .
• a fine grinding step is therefore necessary to achieve a particle size distribution of between 0.1 ⁇ and 20 ⁇ , preferably between 0.5 ⁇ and 5 ⁇ , and more preferably between 1 ⁇ and 3 ⁇ . ⁇ .
• the oxygen-carrying solid is for use in a chemical-loop oxidation-reduction process.
• the invention thus relates to a chemical loop redox process using the oxygen carrier solid as described, or prepared according to the method of preparation as described.
• the oxygen-bearing solid described is used in a CLC process of a hydrocarbon feedstock, in which the oxygen-carrying solid is in the form of particles and circulates between at least one reduction zone and an oxidation zone all operating both in a fluidized bed.
• the temperature in the reduction zone and in the oxidation zone is between 400 ° C. and 1400 ° C., preferably between 600 ° C. and 1100 ° C., and even more preferably between 800 ° C. and 1100 ° C. ° C.
• the hydrocarbon feedstock treated can be a solid, liquid or gaseous hydrocarbon feedstock: gaseous fuels (eg natural gas, syngas, biogas), liquids (eg fuel oil, bitumen, diesel, gasoline, etc.), or solids (ex. : coal, coke, pet-coke, biomass, oil sands, etc.).
• gaseous fuels eg natural gas, syngas, biogas
• liquids eg fuel oil, bitumen, diesel, gasoline, etc.
• solids e. : coal, coke, pet-coke, biomass, oil sands, etc.
• the operating principle of the CLC process in which the oxygen-bearing solid described is used is as follows: a reduced oxygen-carrying solid is brought into contact with an air flow, or any other oxidizing gas, in a zone reaction called air reactor (or oxidation reactor). This results in a depleted airflow and a particle stream of the reoxidized oxygen carrier.
• the stream of oxidized oxygen carrier particles is transferred to a reduction zone called a fuel reactor (or reduction reactor).
• the flow of particles is brought into contact with a fuel, typically a hydrocarbon feedstock. This results in a combustion effluent and a stream of reduced oxygen carrier particles.
• the CLC installation may include various equipment for heat exchange, pressurization, separation or possible recirculation of material around the air and fuel reactors.
• the hydrocarbon feedstock is contacted, preferably cocurrently, with the particulate oxygen-carrying solid comprising the oxido-reducing active mass to carry out the combustion of said feedstock by reducing the oxido-reducing active mass.
• the oxido-reducing active mass M x O y , M representing a metal is reduced to the state via the hydrocarbon feed C n H m , which is correlatively oxidized to C0 2 and H 2 0, according to the reaction (1) already described, or optionally in CO + H 2 mixture according to the proportions used.
• the combustion of the charge in contact with the active mass is carried out at a temperature generally of between 400 ° C. and 1400 ° C., preferably between 600 ° C.
• the contact time varies depending on the type of fuel load used. It typically varies between 1 second and 10 minutes, for example preferably between 1 and 5 minutes for a solid or liquid charge, and for example preferably from 1 to 20 seconds for a gaseous charge.
• a mixture comprising the gases from the combustion and the particles of the oxygen-carrying solid is removed, typically at the top of the reduction zone.
• Gas / solid separation means such as a cyclone, make it possible to separate the combustion gases from the solid particles of the oxygen carrier in their most reduced state.
• These are sent to the oxidation zone to be re-oxidized at a temperature generally between 400 ° C. and 1400 ° C., preferably between 600 ° C. and 1100 ° C., and more preferably between 800 ° C. and 1 ° C. 100 ° C.
• the active mass is restored to its oxidized state M x O y in contact with the air, according to reaction (2) already described (or according to reaction (3) if the oxidizing gas is H 2 0), before returning to the reduction zone, and after being separated from the depleted oxygen air evacuated at the top of the oxidation zone 100.
• the active mass passing alternately from its oxidized form to its reduced form and vice versa, describes an oxidation-reduction cycle.
• the disclosed oxygen carrier solid may also be used in another chemical loop redox process such as a CLR process or a CLOU process.
• the technology used in the chemical loop oxidation reduction process is preferably that of the circulating fluidized bed, but is not limited to this technology, and can be extended to other technologies such as fixed bed, mobile or bubbling bed , or rotating reactor.
• Examples 2 and 3 relate to oxygen carrying solids not in accordance with the invention.
• Examples 4 and 5 relate to oxygen-carrying solids in accordance with the invention.
• Example 1 Aging test for oxygen-carrying solids in a batch fluidized bed
• the aging of the oxygen carrier solids in a batch fluidized bed was carried out in a unit consisting of a quartz reactor, an automated system for supplying the gas reactor and a system for analyzing the gases leaving the reactor. reactor.
• This aging test approximates the conditions of use of the oxygen-carrying solid in a chemically-looped oxidation-reduction process, in particular of a chemical-reduction oxidation-reduction loop.
• the distribution of gases (CH 4 , CO 2 , N 2 , air) is ensured by mass flow meters. For safety reasons, a nitrogen sweep is carried out after each period of reduction and oxidation.
• the height of the quartz reactor is 30 cm, with a diameter of 4 cm in its lower part (on 24 cm high), and 7 cm in its upper part.
• a quartz sinter is placed at the bottom of the reactor to ensure the distribution of the gases and a good fluidization of the particles.
• Another sinter is placed in the upper part of the reactor to prevent the loss of fines during the test.
• the reactor is heated using an electric oven. Part of the gas leaving the reactor is pumped to the gas analyzers, cooled to condense most of the water formed during the reduction and then dried with calcium chloride.
• the gas concentrations are measured using non-dispersive infrared analyzers for CO, CO 2 and CH 4 , a paramagnetic analyzer for oxygen, and a TCD detector for hydrogen.
• Standard test conditions 100 grams of particles are introduced into the quartz reactor and then heated to 900 ° C under air flow (60 Nl / h). When the temperature of the bed is stabilized at 900 ° C. in air, 250 cycles are carried out according to the following steps:
• the conversion of the oxygen-carrying solid (amount of oxygen supplied by the oxygen-carrying solid to carry out the methane conversion, expressed in% by weight of the oxidized oxygen carrier) is calculated from the gas conversion data, and the reduction time (step 2 of the cycle) is adjusted after the first cycle so that the oxygen-bearing solid releases about 2% by weight of oxygen (relative to the oxidized mass of oxygen carrier solid introduced) at each reduction cycle.
• the oxidation time (step 4 of the cycle) is sufficient to completely reoxidize the particles (15 min).
• Particle size distribution was measured using a Malvern particle size analyzer, using Fraunhofer's theory.
• the mercury porosimetry measurements were performed on the Autopore IV device marketed by Micromeritics, considering a mercury surface tension of 485 dyn / cm and a contact angle of 140 °.
• the minimum pore size measurable by mercury porosimetry is 3.65 nm.
• the nitrogen adsorption isotherms were carried out on the ASAP 2420 device marketed by Micromeritics.
• an oxygen-carrying solid is formed from alumina as a support matrix for an active oxide-reduction mass of copper oxide (s).
• the alumina used for this example is Puralox SCCa 150-200 marketed by Sasol.
• the pore volume of the particles measured by mercury porosimetry is 0.450 ml / g, and the pore size distribution is between 5 and 15 nm, centered on 9 nm.
• the macroporous volume of the support measured by mercury porosimetry is 0.007 ml / g (1.5% of the total pore volume).
• the nitrogen adsorption isotherm of Puralox makes it possible to measure a specific surface area of 199 m 2 / g, a microporous volume (pore size ⁇ 2 nm) and a mesoporous volume (2 nm ⁇ pores ⁇ 50 nm) of 0.496 ml / boy Wut.
• the pore volume of the particles of the solid obtained, measured by mercury porosimetry, is 0.367 ml / g, of which 0.015 ml / g (ie 4% of the total pore volume measured by mercury porosimetry) is due to the macroporosity.
• the pore size distribution is between 5 and 20 nm and centered on 11.25 nm, as can be seen in the diagram of FIG. FIG.
• the nitrogen adsorption isotherm of the oxygen-carrying solid according to this example makes it possible to measure a surface area of 135 m 2 / g, a microporous volume (pore size ⁇ 2 nm) and a mesoporous volume (2 nm ⁇ pores ⁇ 50 nm) of 0.404 ml / g.
• the oxygen carrier solid according to this example was aged under the conditions described in Example 1.
• FIG. 1B is a diagram showing the normalized conversion rate Xc of methane as a function of the number N of oxidation-reduction rings in a CLC process using the oxygen carrier solid according to example 2.
• the conversion of methane is of the order of 98% at the beginning of the test, it increases until reaching 100%, then a progressive deactivation is observed after the hundredth cycle. The conversion then stabilizes around 95%.
• the nature of the active mass used causes the appearance of oxygen during the nitrogen sweeping step.
• the particles can therefore be used indifferently in a CLC or CLOU type process.
• SEM slices on a polished section of the particles after the aging test according to Example 1, such as the plate of FIG. 1D, show that the constitutive aluminic matrix of the particles did not resist the 250 successive redox cycles. Most of the particles are actually in the form of small fragments (a few tens of ⁇ ). In addition, additional SEM-EDX analyzes show that the finest particles observed (some ⁇ in size) consist almost exclusively of copper and oxygen.
• Example 3 Carbohydrate carrying solid CuO / Silica Alumina at 5% SiO 2
• an oxygen-carrying solid is formed from silicified alumina at 5% of SiO 2 as a support matrix for an active oxide-reduction mass of copper oxide (s) (CuO and CuAl 2 O 4 ).
• the siliceous alumina used is Siralox 5 marketed by Sasol and which contains
• the pore volume measured by mercury porosimetry of the alumino-silicic support is 0.549 ml / g, and the pore size distribution is between 5 and 30 nm, centered on 13 nm.
• the macroporous volume is 0.033 ml / g, ie 6% of the total pore volume measured by mercury porosimetry.
• the nitrogen adsorption isotherm of Siralox 5 makes it possible to measure a specific surface area of 173 m 2 / g, a microporous volume (pore size ⁇ 2 nm) and a mesoporous volume (2 nm ⁇ pores ⁇ 50 nm) of 0.601 ml. /boy Wut.
• 240 g of siliceous alumina were impregnated according to the dry impregnation method, with 109 g of copper nitrate trihydrate in aqueous solution. After drying at 120 ° C. and calcining at 1000 ° C. for 12 hours, a solid containing 13% by weight of CuO equivalent is obtained.
• the crystallographic phases detected by XRD are ⁇ - ⁇ 2 0 3 , ⁇ - ⁇ 2 0 3 , CuAl 2 O 4 and CuO.
• the SEM backscattered electron (a) on polished section and the EDX (b) mapping of FIG. 2C show that the copper is relatively well dispersed inside the particles, but in a less homogeneous manner than in example 2.
• the pore volume of the particles measured by mercury porosimetry is 0.340 ml / g, of which 0.029 ml / g (8.5%) is due to macroporosity.
• the pore size distribution is between 7 and 50 nm and centered on 15 nm, as can be seen in the diagram of FIG. 2A representing the volume of mercury injected Vi (ml / g) in the porosity, as well as the ratio dV / dD, as a function of the pore diameter (nm), for the oxygen carrier solid according to this example.
• the particles after impregnation / calcination are essentially mesoporous.
• the specific surface area measured by nitrogen adsorption is 77 m 2 / g.
• the oxygen carrier solid according to Example 3 was aged under the conditions described in Example 1.
• the nature of the active mass used causes the appearance of oxygen during the nitrogen sweeping step.
• the particles can therefore be used indifferently in a CLC or CLOU type process.
• the partial conversion of methane relative to Example 2 is not a problem with respect to the CLC or CLOU process on an industrial scale, the total conversion of the fuel can be achieved by modifying the residence times of the particles. , gas velocities and / or inventory in the reduction reactor.
• the size distribution of the particles after the aging test is similar to that of the material before testing, which indicates a better mechanical strength of the alumina-silica matrix compared to the particles on pure alumina.
• the zone of the particles whose morphology is relatively unchanged compared to the initial silica-alumina consists mainly of alumina and contains only traces of copper, as well as almost all the silicon.
• the presence of silicon in the ceramic matrix thus makes it possible to stabilize said ceramic matrix.
• all the copper initially well dispersed in the mesoporous matrix migrated to the periphery of the particles during successive redox cycles.
• the particles of the oxygen-carrying solid are prepared from the synthesis of inert and stable oxide-type ceramic matrix particles serving as a support for the oxidation-reduction active mass (supports not marketed).
• the particles of the oxygen-carrying solid are prepared in the following manner:
• Aluminosilicic synthetic materials are formulated and formulated from aqueous suspensions which have been spray-dried to result in microspherical solid particles, otherwise known as granules or microspheres.
• the step of formulating the oxide support corresponds to adjusting the nature and the composition (percentage content by weight) of the materials or precursors used in the starting suspension.
• the selected raw materials in solid or liquid form according to their physico-chemical properties
• they are then mixed with deionized water, acting as a solvent, in a stirred tank in order to obtain a fluid aqueous suspension and stable.
• This suspension is then transferred to a spray dryer where it is sprayed into fine droplets which, during the drying and evaporation phase of the water, will form solid spherical particles with a size close to one hundred ⁇ .
• an oxygen carrier solid comprising a ceramic alumina matrix in which is dispersed an active oxide redox oxide (s) active mass.
• the oxygen-carrying solid according to this example is obtained from an aqueous suspension of alumina, using in particular the spray drying technique.
• the alumina used for this example is a powder obtained from a semi-industrial batch production which was obtained from an aqueous suspension of alumina by means of the spray-drying process, as described above in FIG. embodiment and preparation of the oxygen carrier solid.
• the weight ratio relative to the weight of particles of oxides in suspension is 10.6% by weight for the inorganic binder (boehmite) and 5.2% by weight for the organic binder (PVA).
• the suspension is spray-dried: the homogenized suspension is pumped and then sprayed into fine droplets, using a partially positioned pneumatic nozzle. high of a drying chamber. Then, bringing the droplets into contact with an air stream heated to 300 ° C induces evaporation of the water and progressive drying, which leads to solid spherical particles collected at the bottom of the drying chamber. , and having a size between 30 ⁇ and 200 m.
• the particles obtained constitute the final oxide support, and this final oxide material is composed of 100% by weight of alumina (Al 2 O 3 ).
• the pore volume measured by mercury porosimetry of the alumina support is 0.76 ml / g, and a bimodal pore size distribution is observed.
• the pore size distribution for the mesoporosity is between 5 and 50 nm (centered on 9.6 nm) and for the macroporosity is between 50 and 2800 nm (centered on 385 nm).
• the macroporous volume is 0.37 ml / g, ie 49% of the total pore volume measured by mercury porosimetry.
• the X-ray diffraction shows that Cu (CuAl 2 O 4 ) sub-stoichiometric copper aluminate is formed, as well as some CuO.
• the pore volume measured by mercury porosimetry of the alumina support is 0.643 ml / g, and a bimodal pore size distribution is observed.
• the total pore volume consists of 50% of mesopores with a size of between 7 and 50 nm, and 50% of macropores with a size of between 50 nm and 3 ⁇ , centered on 400 nm.
• Vi refers to the porosity of the particles of the initial oxygen carrier (before aging test).
• the grain density of the oxygen-bearing solid is 987 kg / m 3 .
• the SEM image of FIG. 3B on a polished section shows a particle of the spherical oxygen carrier. The small contrast difference in backscattered electrons between the constituent grains of the oxygen carrier indicates that the copper is dispersed homogeneously within the particle.
• the aging of the particles in a batch fluidized bed was carried out according to the same protocol as in Example 1.
• the nature of the active mass used causes the appearance of oxygen during the nitrogen sweeping step.
• the particles can therefore be used indifferently in a CLC or CLOU type process.
• the particle size distribution after the aging test is similar to that of the pre-test material.
• the main crystalline phases detected by DRX after aging are tenorite (CuO) and alpha alumina. Some low intensity peaks characteristic of copper aluminate (CuAl 2 O 4 ) are also present.
• Example 2 In contrast to the observations of Example 2, the aluminum matrix has withstood the redox cycles well.
• the copper distribution after 250 cycles in a batch fluidized bed within the particles of the oxygen carrier according to the invention remains relatively homogeneous, with a markedly minimized tendency of the copper to migrate towards the periphery of the particles with respect to Example 3.
• Cuprous nodules of size between 0.1 ⁇ and 5 ⁇ are observed in the macroporosity of the particles of the solid carrier of oxygen, as well as some areas where copper is more dispersed and associated with aluminum (CuAI 2 0 4 ).
• the total pore volume of the particles measured by mercury porosimetry (0.637 ml / g) has changed little, and consists essentially of macroporosity (0.634 ml / g). Virtually all of the initial mesoporosity associated with the use of gamma alumina has disappeared to form macroporous alpha alumina in which the copper remains dispersed.
• the pore size after 250 cycles varies between 200 nm and 3.5 ⁇ , and is centered on 700 nm.
• the alumina matrix has therefore sintered, but the pore size distribution and the pore volume limit the migration of copper within the particles. This distribution is visible in FIG. 3D, where Vi refers to the porosity of the particles of the oxygen carrier after the aging test.
• the initially macroporous ceramic matrix has withstood very well the 250 successive redox cycles and the copper remains dispersed in the form of small nodules within the macroporosity developed by the matrix.
• the textural evolution of the particles is relatively small.
• an oxygen-carrying solid comprising a silica-alumina ceramic matrix (13% SiO 2 ) within which is dispersed an oxidation-reduction active mass of copper oxide (s). .
• the oxygen carrier solid according to this example is obtained from an aqueous suspension comprising alumina and silicic acid, in particular using the spray drying technique.
• the siliceous alumina used for this example is a powder resulting from a semi-industrial batch production which was obtained by granulation of an aqueous suspension of alumina and silica using the spray drying method, as described in the embodiment and preparation of the oxygen carrier solid.
• silicic acid Si [OH] 4 concentrated to 50 g of Si0 2 per
• the weight ratio relative to the weight of particles of oxides in suspension is 15% by weight for the inorganic binders (boehmite and silicic acid) and 3.3% by weight for the organic binder (PVA).
• the suspension is spray-dried: the homogenized suspension is pumped and then sprayed into fine droplets, by means of a pneumatic nozzle positioned at the top. a drying chamber. Then, bringing the droplets into contact with an air stream heated to 300 ° C induces evaporation of the water and progressive drying, which leads to solid spherical particles collected at the bottom of the drying chamber. , and having a size between 30 ⁇ and 200 ⁇ .
• the particles obtained constitute the final oxide support, and this final oxide material is composed of 87.1% by weight of alumina (Al 2 O 3 ) and 12.9% by weight of silica (SiO 2 ).
• the pore volume measured by mercury porosimetry of the alumina support is 0.94 ml / g, and a bimodal pore size distribution is observed.
• the pore size distribution for the mesoporosity is between 4 and 50 nm (centered on 9.8 nm) and for the macroporosity is between 50 and 1000 nm (centered on 426 nm).
• the macroporous volume is 0.51 ml / g, ie 54% of the total pore volume measured by mercury porosimetry.
• the X-ray diffraction shows that a Cu sub-stoichiometric copper aluminate (CuAl 2 O 4 ) is formed.
• An amorphous band between 17 and 28 ° 2 ⁇ corresponding to non-crystalline silica is also present.
• the pore volume measured by mercury porosimetry of the oxygen-carrying solid is 0.808 ml / g, and a bimodal pore size distribution is observed.
• the total pore volume consists of 57% of mesopores with a size of between 7 and 50 nm, and 43% of macropores with a size of between 50 nm and 900 nm, centered on 430 nm. This distribution is visible in FIG. 4A, where Vi refers to the porosity of the particles of the initial oxygen carrier (before aging test).
• the grain density of the oxygen-carrying solid is 880 kg / m 3 .
• the SEM image of FIG. 4B on a polished section shows a particle of the substantially spherical oxygen carrier.
• the small contrast difference in backscattered electrons between the constituent grains of the oxygen carrier indicates that the copper is dispersed homogeneously within the particle.
• the aging of the particles in a batch fluidized bed was carried out according to the same protocol as in example 1.
• the conversion of methane to H 2 0 and C0 2 visible in the diagram of FIG. 4C displaying the conversion of methane (standardized) depending on the oxidation-reduction cycles during the test, is stable, of the order of 99% over the entire test.
• the nature of the active mass used causes the appearance of oxygen during the nitrogen sweeping step.
• the particles can therefore be used indifferently in a CLC or CLOU type process.
• the particle size distribution after the aging test is similar to that of the pre-test material.
• the main crystalline phases detected by DRX after aging are tenorite (CuO), copper aluminate (CuAl 2 O 4 ), mullite (Al 6 Si 2 O 13), delta alumina and alpha alumina.
• the distribution of copper after 250 cycles in a batch fluidized bed within the particles of the oxygen-carrying solid according to the invention remains relatively homogeneous, with a markedly minimized tendency for the copper to migrate towards the periphery of the particles with respect to Example 3
• a particle section of the oxygen-carrying solid after the test is observed, for example, the presence of cuprous nodules of between 0.1 ⁇ and 5 ⁇ uniformly distributed in the region. macroporosity, as well as large areas with copper overconcentration (in light gray, probably CuAI 2 0 4 ).
• the total pore volume of the particles measured by mercury porosimetry (0.302 ml / g) was greatly reduced and consisted essentially of macroporosity (0.267 ml / g).
• the presence of silicon in the aluminum matrix causes a behavior different from that of pure alumina during the redox cycles. More densification of the ceramic matrix is observed.
• the residual mesoporous volume represents only 1 1% of the total pore volume and is probably related to the presence of CuAl 2 O 4 and / or delta alumina.
• the macroporous volume has decreased relatively little compared to the initial state.
• the pore size after 250 cycles varies between 50 nm and 2.8 ⁇ , and is centered on
• the alumino-silicic matrix has sintered, but the pore size distribution and the pore volume limit the migration of copper within the particles. This distribution is visible in FIG. 4D, where Vi refers to the porosity of the particles of the oxygen carrier after the aging test.
• the morphological evolution of the oxygen-carrying solid according to the invention thus makes it possible to envisage the prolonged use of these particles in an industrial redox process in chemical looping, in particular in a circulating fluidized bed.

Applications Claiming Priority (2)

Publications (1)

Family

ID=58401796

Family Applications (1)

Country Status (8)

Cited By (1)

Families Citing this family (8)

Family Cites Families (10)

• 2016
  • 2016-12-23 FR FR1663301A patent/FR3061036B1/fr active Active
• 2017
  • 2017-12-21 BR BR112019011679A patent/BR112019011679A2/pt not_active Application Discontinuation
  • 2017-12-21 AU AU2017383045A patent/AU2017383045A1/en not_active Abandoned
  • 2017-12-21 EP EP17822300.4A patent/EP3558515A1/de active Pending
  • 2017-12-21 WO PCT/EP2017/084208 patent/WO2018115344A1/fr unknown
  • 2017-12-21 CA CA3045420A patent/CA3045420A1/fr active Pending
  • 2017-12-21 US US16/471,499 patent/US11717811B2/en active Active
  • 2017-12-21 CN CN201780079798.5A patent/CN110225795B/zh active Active

Also Published As

Similar Documents

Legal Events