Product comprising lithium bayerite and process for manufacturing such a product

Abstract

The present invention relates to a product comprising: - water, and - crystallites, at least a part, preferably substantially all of said crystallites being made of lithiated bayerite, the average size of the lithiated bayerite crystallites being greater than or equal to 10 nm and less than or equal to 25 nm, and said product having a cumulative rate of aluminium hydroxide and boehmite less than or equal to 10%, said product comprising at least the elements Li, Cl, Al, O and H, the elements Li, Cl and Al being present in said dry product in the following amounts, determined by inductively coupled plasma spectrometry, in weight percentages: - 2% < Li < 5%, - 10% < Cl < 26%, - 15% < Al < 30%.

Description

Title of the invention: Product comprising lithium bayerite and method for manufacturing such a product technical field

[0001] The present invention relates to a product comprising lithium bayerite and to a method for manufacturing a product comprising lithium bayerite. Prior art

[0002] The use of lithium, particularly in batteries, is constantly increasing.

[0003] Brines are sources of lithium, for which an extraction of said lithium is necessary.

[0004] This extraction, or capture, can be carried out using columns filled with an active material, which selectively and reversibly captures lithium when the brine is in contact with it.

[0005] The lithium is then recovered by passing an aqueous solution through these columns. This results in a concentrated lithium solution which is purified before a precipitation step, generally in the form of lithium carbonate.

[0006] Lithium adsorbents, in particular lithium bayerite, are advantageously used materials as an active material enabling the obtaining of the concentrated lithium solution within the extraction columns.

[0007] FR3053264 describes a process for preparing a crystallized solid material of formula (LiCl)x.2Al(OH)3, nH20 with x between 0.4 and 1 and n between 0.01 and 10.

[0008] US4,348,295 describes a process for manufacturing LiX.2Al(OH)3, nH2O, X being a anion forming an acid in molecular combination with H or forming a salt in combination with a metal ion, said process comprising a step of reacting hydrated alumina with a concentrated LiX solution at a temperature above 85°C. However, the material obtained by this process exhibits a limited lithium adsorption capacity.

[0009] There is a need for a manufacturing process for a product containing lithium bayerite, which yields a product with a high lithium adsorption capacity. The object of the invention is to satisfy this need. Description of the invention

[0010] According to the invention, this goal is achieved by means of a product comprising, and preferably essentially consisting of:

[0011] - water, and

[0012] - crystallites, at least a part, preferably substantially all, of said crystallites being composed of lithiated bayerite,

[0013] the average size of the lithia-bearing bayerite crystallites being greater than or equal to 10 nm and less than or equal to 25 nm, and

[0014] said product having a cumulative level of aluminium hydroxide and boehmite less than or equal to 10%,

[0015] said product comprising at least the elements Li, Cl, Al, O and H,

[0016] the elements Li, Cl and Al being present in said dry product in the following amounts, determined by inductively coupled plasma spectrometry, in weight percentages:

[0017] - 2% < Li < 5%

[0018] -10% <Cl<26%,

[0019] - 15% < Al < 30%.

[0020] The average size of the lithiated bayerite crystallites and the cumulative rate of aluminium hydroxide and boehmite are measured on said product after exposure to air for 170 hours at 25°C, at atmospheric pressure.

[0021] Said dry product is obtained after drying under air at 200°C for 16 hours, at atmospheric pressure.

[0022] According to preferred but non-limiting embodiments of the present invention, which may, where appropriate, be combined with each other: - The product has the following chemical analysis, determined on the dry product by inductively coupled plasma spectrometry, in weight percentages: - Li in a content greater than 2% and less than 5%, and - Cl in a content greater than 10% and less than 26%, and - Aluminum in a content greater than 15% and less than 30%, and - Elements other than Li, Cl, Al, O and H in a content of less than 3%, And - O and H in a content corresponding to the complement to 100%; - the average size of the lithiated bayerite crystallites is less than 23 nm; - the water content is greater than 1%, preferably greater than 5%, of preference greater than 10% and / or preference less than 95%, preference less than 80%, preference less than 70%; - the cumulative rate of aluminium hydroxide and boehmite is less than or equal to 8%, preferably less than or equal to 5%; - The crystalline phases of the product comprise lithiased bayerite, boehmite and / or an aluminum hydroxide selected from gibbsite, bayerite, doyleite, nordstrandite and mixtures thereof; preferably the crystalline phases of the product comprise lithiased bayerite and an aluminum hydroxide selected from gibbsite, bayerite, doyleite, nordstrandite and their mixtures; - the only crystalline phase present in the product is lithia-treated bayerite; - the product consists of at least 80%, by mass, of water and lithiased bayerite crystallites, and aluminium hydroxide and / or boehmite, and LiCl, and a binder, preferably the product consists of at least 80%, by mass, of water and lithiased bayerite crystallites, and aluminium hydroxide, and LiCl, and a binder, preferably the product consists of at least 80%, by mass, of water and lithiased bayerite crystallites, and LiCl, and a binder, said binder being preferably a polysaccharide, preferably an alginate.

[0023] The invention also relates to a method for manufacturing a product according to the invention and as previously described, comprising the following steps: a. Suspension in aqueous solution of an aluminum source, preferably a single aluminum source, selected from boehmite or aluminum hydroxide and mixtures thereof, preferably aluminum hydroxide, grinding said aqueous suspension so as to obtain a median size less than or equal to 3 pm if the median size of said aluminum source is greater than 3 pm, said suspension being maintained during this step a) at a temperature below 50°C, b. Increasing the pH by adding a base, such that the molar ratio between the OH supplied by said base and the Ai present in the mixture is greater than 0.20, said mixture being kept agitated after introduction of said base, at a temperature below 50°C; c. Addition of a chlorine salt, such that the molar ratio between the Cl supplied by said chlorine salt and the Al present in the mixture is greater than 0.25, said mixture being kept agitated after introduction of said chlorine salt at a temperature below 50°C; the base in step b), the chlorine salt in step c) and their respective quantities being chosen so as to supply an amount of lithium in the mixture such that the Li / Al molar ratio is greater than or equal to 1; d. Raising the temperature of the mixture to a temperature greater than or equal to 50°C and less than or equal to 60°C, the time ti being the time during which said mixture is at a temperature greater than or equal to 50°C; e. Maintaining the mixture at a temperature greater than or equal to 50°C and less than or equal to 60°C for a time t2; f. Optionally, add an acid to the mixture, while stirring, so as to lower the pH of the mixture to a value less than or equal to 8, the salt of chlorine in step c), said acid, and their respective quantities being chosen so that the Cl / Al molar ratio in the mixture is greater than or equal to 1, the mixture being maintained at a temperature less than or equal to 60°C, time t3 being the time during which the mixture is at a temperature greater than or equal to 50°C, the molar ratio between the Cl supplied by the chlorine salt and the Ai present in the mixture in step c) being greater than or equal to 0.5 if the process does not include said step f); g. Optionally, and preferably, filtering the mixture to obtain a paste, the mixture being maintained at a temperature less than or equal to 60°C, time t4 being the time during which the mixture is at a temperature greater than or equal to 50°C;

[0024] the cumulative time t,+t2+t3+t4 = t5 being greater than or equal to 45 minutes and less than 15 hours.

[0025] According to preferred but non-limiting embodiments of the present invention, which may, where appropriate, be combined with each other: - Step a) includes the implementation of a grinding of the aqueous suspension of an aluminium source chosen from an aluminium boehmite or aluminium hydroxide and their mixtures, so as to obtain a median size < 1 pm; - time t5 is such that times t2, t3, and t4 satisfy the following relations: [t, / (-1,2T,+75)] + [t2 / (-1,2T20+75)] + [t3 / (-1,2T30+75)] + [t4 / (-1,2T40+75)] < 1, preferably [t, / (-0,8T,+50)] + [t2 / (-0,8T20+50)] + [t3 / (-0,8T30+50)] + [1, / (-0,8T40 +50)] < 1, preferably [t, / (-0,55T,+34,5)] + [t2 / (-0,55T20+34,5)] + [t3 / (-0,55T30+34,5)] + [t4 / (-0.55T40+34.5)] < 1, and [t, / (-0.225T,+14.25)] + [t2 / (-0.225T20+14.25)] + [t3 / (-0.225T30+14.25)] + [t, / (-0.225T40+14.25)] > 1, preferably [t, / (-0.2T,+13)] + [t2 / (-0.2T20+13)] + [t3 / (-0.2T30+13)] + [t4 / (-0.2T40 +13)] > 1, with T being the temperature reached by the mixture in step d), T20 being the average temperature during step e), T30 being the average temperature during step f), T40 being the temperature average of the mixture during time t4; - aluminum hydroxide, boehmite and their mixtures are the only sources of aluminum used in all stages of the process, preferably aluminum hydroxide is the only source of aluminum used in all stages of the process; - in step b), the molar ratio between the OH provided by the base and the Ai present in the mixture is greater than 0.25 and less than 10; - in step b), the pH of the mixture after the addition of the base is greater than 9 and less than 13; - at step c), the molar ratio between the Cl supplied by the chlorine salt and the Ai present in the mixture is less than 10; - the base in step b), the chlorine salt in step c), and their respective quantities are chosen so as to provide an amount of lithium in the mixture such that the Li / Al molar ratio is greater than 1.1 and less than 4; - at step d), the time ti is greater than 5 minutes; - at step e), the temperature of the mixture is substantially constant; - at step e), the time t2 is greater than 40 minutes; - in step f) (optional), at least part of the required amount of Cl to obtain a Cl / Al molar ratio greater than or equal to 1 is provided by the acid; - in optional step f), the pH of the mixture is decreased to a value less than 7.5, and greater than 6.5; - in optional step f), the Cl / Al molar ratio in the mixture is set to a value less than 3; - in optional step f), the temperature of the mixture is substantially constant; - at optional step f), the time t3 is greater than 5 minutes; - at step g), the time t4 is less than 15 minutes; - steps a) and b) are carried out simultaneously; - steps a), b) and c) are carried out simultaneously; - the process includes, after step g), a step h) of shaping a starting charge comprising the paste obtained at the end of step g), in the form of an object or a coating, preferably in the form of an object, and an optional step i) of reducing the water content of said object or said coating; - at step h), the starting charge includes a binder, preferably a polysaccharide comprising a group capable of forming an ionic bond with a gelling agent for the formation of a gelled polysaccharide, preferably a polysaccharide selected from alginates; - steps h) and i) are carried out, at least partially, simultaneously.

[0026] The invention finally relates to a lithium capture device, in particular an extraction column, comprising a product according to the invention or a product obtained by the process according to the invention as described above. Definitions

[0027] - The compound with the formula LiC1.2Al(OH)3.xH2O, as indicated in the ICDD PDF datasheet 00-031-0700, is called "lithia-bearing bayerite," but also by extension, compounds having a ratio of the molar amounts of lithium and aluminium, Li / Al, different from 0.5. In some modes, it may be less than 0.5. According to other modes, it may be greater than 0.5. - The compound with the formula A1(OH)3 is called "aluminum hydroxide". Gibbsite, bayerite, doyleite and nordstrandite are aluminum hydroxides. - The compound with the formula y-AlO(OH) is called "boehmite". - The "cumulative percentage of aluminium hydroxide and boehmite", in %, in a product, is calculated according to the following formula (1):

[0028] T = 100* (Aha + ABO) / (Aha + Abo + ABL) (1)

[0029] where - Aha is the sum of the areas of the aluminium hydroxide phases, measured on an X diffraction pattern of said product, for example obtained from an X'Pert diffractometer of the Panalytical company, equipped with a copper DX tube, without deconvolution treatment, after having eliminated the Ka2 line. The area of ​​an aluminium hydroxide phase is that of its diffraction peak located in an angular domain 20 approximately equal to 18.3°; - Ab0 is the diffraction peak of boehmite located in an angular domain of approximately 14°, measured on the same diagram, without deconvolution processing, after eliminating the Ka2 line - Abl is the area of ​​the diffraction peak of the (003) plane of the lithiated bayerite located in an angular domain 20 approximately equal to 11.3°, measured on the same diagram, without deconvolution treatment, after eliminating the Ka2 line. - According to the classical definition, "polysaccharides" are polymers composed of chains of sugar units linked by glycosidic bonds. - A polysaccharide capable of forming a gel under the action of a gelling agent is called a "gelable polysaccharide". A gelled polysaccharide results from the association of polysaccharide chains under the action of a gelling agent. For example, alginate has the formula (C6H7O6)n. Alginate is a polysaccharide chain containing carboxylate groups (COO). Calcium ions (Ca2+) (the gelling agent) react with two strands of alginate, that is, with the carboxylate groups (COO), leading to the polymerization of the chains. of alginate and the bonding of the molecules together. The reaction thus allows the creation of a gel. - The term "dry product" means a product obtained after drying under air at 200°C for 16 hours (at atmospheric pressure), this drying being classically carried out, for example, in an oven. The "median size" of a powder or suspension of particles is defined as the size that divides the particles of the powder or suspension into first and second populations of equal mass, these first and second populations consisting only of particles with a size greater than or equal to, or less than, respectively, the median size. The median size can, for example, be determined using a laser particle size analyzer.

[0030] All percentages in this description are percentages by mass unless otherwise stated.

[0031] The verbs "contain", "understand" and "present" should be interpreted broadly, without limitation, unless otherwise indicated. Detailed description

[0032] A product according to the invention has one or more of the following optional characteristics: - A water content greater than 1%, preferably greater than 5%, preferably greater than 10% and / or preferably less than 95%, preferably less than 90%, preferably less than 80%, preferably less than 70%, or even less than 60%. The water content is the mass loss, expressed as a percentage, after drying at 200°C for 16 hours in air, at atmospheric pressure; - An average size of the lithia-treated bayerite crystallites of less than 23 nm, preferably less than 20 nm; - A cumulative level of aluminium hydroxide and boehmite less than or equal to 8%, preferably less than or equal to 5%, preferably substantially zero; The crystalline phases preferably consist of lithiased bayerite, boehmite, and / or an aluminum hydroxide selected from gibbsite, bayerite, doyleite, nordstrandite, and mixtures thereof, preferably gibbsite. Preferably, the only crystalline phase is lithiased bayerite. The determination of the crystalline phases and the determination of the rate cumulative aluminum hydroxide and boehmite and the measurement of the size of the lithiated bayerite crystallites are carried out on the product after exposure to air for 170 hours at 25°C, at atmospheric pressure; The elements Li, Cl and Al are present in the said product, after drying in air at 200°C for 16 hours, at atmospheric pressure, in the following concentrations, as weight percentages: - Li: preferably greater than 2.5%, preferably greater than 3%, and / or preferably less than 4.5%, preferably less than 4%, and - Cl: preferably greater than 11%, preferably greater than 13% and / or preferably less than 24%, preferably less than 22%, and - Al: preferably greater than 17%, preferably greater than 19% and / or preferably less than 28%, preferably less than 26%; After drying in air at 200°C for 16 hours, at atmospheric pressure, the following chemical analysis, determined by inductively coupled plasma spectrometry, in weight percentages: - Li in a content greater than 2%, preferably greater than 2.5%, preferably greater than 3% and less than 5%, preferably less than 4.5%, preferably less than 4%, and - Cl in a content greater than 10%, preferably greater than 11%, preferably greater than 13% and less than 26%, preferably less than 24%, preferably less than 22%, and - Al in a content greater than 15%, preferably greater than 17%, preferably greater than 19% and less than 30%, preferably less than 28%, preferably less than 26%, and - Elements other than Li, Cl, Al, O and H in a content of less than 3%, preferably less than 2%, preferably less than 1%, and - O and H in a content corresponding to the complement to 100%; After drying under air at 200°C for 16 hours, at atmospheric pressure, the product has a Li / Al mass ratio greater than 0.1, preferably greater than 0.15 and / or preferably less than 0.3, preferably less than 0.25; After drying in air at 200°C for 16 hours at atmospheric pressure, the product has a Li / Cl mass ratio greater than 0.08, preferably greater than 0.1, preferably greater than 0.13, preferably greater than 0.15 and / or preferably less than 0.4, preferably less than 0.3, preferably less than 0.25; The product consists of at least 80%, preferably more than 85%, preferably more than 90%, preferably more than 95%, preferably more than 99% by mass, of water and crystallites of lithiated bayerite, and aluminum hydroxide and / or boehmite, and LiCl, and a binder, preferably a polysaccharide, preferably a gelled polysaccharide, preferably an alginate, preferably a gelled alginate. Preferably, the product consists of at least 80%, preferably more than 85%, preferably more than 90%, preferably more than 95%, preferably more than 99% by mass, of water and said crystallites and aluminium hydroxide and LiCl and a binder, preferably a polysaccharide, preferably a gelled polysaccharide, preferably an alginate, preferably a gelled alginate.Preferably, the product consists of at least 80%, preferably more than 85%, preferably more than 90%, preferably more than 95%, preferably more than 99% by mass, of water and said crystallites and LiCl and a binder, preferably a polysaccharide, preferably an alginate; . The product is in the form of objects having the shape of cylinders, polylobates, rings, or spheres. Preferably, said objects have a largest dimension less than 100 mm, preferably less than 80 mm, preferably less than 50 mm, preferably less than 30 mm, or even less than 10 mm and / or a smallest dimension, measured in a plane perpendicular to the direction of the largest dimension, greater than 1pm, or even greater than 10 pm (micrometers); The product is in the form of a coating applied to a substrate. Preferably, the thickness of said coating is greater than 10 µm, preferably greater than 50 µm, preferably greater than 100 µm, preferably greater than 200 µm, and preferably less than 1 mm, preferably less than 500 µm. Preferably the substrate is made of a material selected from ceramics, metals, organic products, in particular polymers, and mixtures thereof; When the product contains a polysaccharide, preferably a gelled polysaccharide, preferably an alginate or a pectin, preferably a gelled alginate or a gelled pectin, preferably an alginate, preferably a gelled alginate, the mass quantity of the polysaccharide, preferably the gelled polysaccharide, is greater than or equal to 0.1%, preferably greater than or equal to 0.2%, preferably greater than or equal to 0.3% and less than or equal to 5%, preferably less than or equal to 4%, of preferably less than or equal to 3%, preferably less than or equal to 2%, preferably less than or equal to 1%. The polysaccharide, the alginate, contained in the binder can, for example, be detected by size exclusion chromatography.

[0033] A product according to the invention can be manufactured according to a process according to the invention comprising steps a) to g), in particular and preferably steps a) to i) mentioned above.

[0034] In step a), an aluminum source chosen from boehmite or aluminum hydroxide and mixtures thereof, preferably aluminum hydroxide, is suspended in aqueous suspension, and

[0035] if the median size of said aluminum source is greater than 3 pm, said aqueous suspension is ground so as to obtain a median size less than or equal to 3 pm, preferably less than or equal to 2 pm, preferably less than or equal to 1 pm, preferably less than or equal to 0.7 pm, preferably less than or equal to 0.5 pm,

[0036] said suspension being maintained during this step a) at a temperature below 50°C.

[0037] The aqueous suspension of the aluminum source and the grinding of said aqueous suspension can be carried out simultaneously.

[0038] Preferably, the grinding of the aqueous suspension is carried out if the median size of the aluminum source is greater than 2 pm, greater than 1 pm.

[0039] In a preferred embodiment, an aqueous suspension of an aluminum source chosen from a boehmite or an aluminum hydroxide and mixtures thereof, preferably an aluminum hydroxide, is ground to obtain a median size < 1 pm, said suspension being maintained during this step at a temperature below 50°C.

[0040] Preferably the aluminium hydroxide is gibbsite.

[0041] Preferably, aluminum hydroxide, boehmite, and mixtures thereof are the only sources of aluminum used in all the steps of the process according to the invention. Preferably, aluminum hydroxide is the only source of aluminum used in all the steps of the process according to the invention.

[0042] Preferably, the median size obtained after grinding is less than or equal to 0.7 pm, preferably less than or equal to 0.5 pm.

[0043] Preferably, the suspension is maintained during step a) at a temperature above 15°C, preferably greater than or equal to 20°C.

[0044] Grinding can be carried out according to any technique known to a person skilled in the art, such as wet grinding.

[0045] In step b), the pH of the mixture obtained at the end of step a) is increased by the addition of a base, in such a way that the molar ratio between the OH supplied by said base and the Ai present in the mixture is greater than 0.20, said mixture being kept in agitation after introduction of said base, at a temperature below 50°C.

[0046] Preferably, the molar ratio between the OH supplied by said base and the Ai present in the mixture is greater than 0.25, preferably greater than 0.4, preferably greater than or equal to 0.5, and / or preferably less than 10, preferably less than 9, preferably less than 8, preferably less than 7, preferably less than 6, preferably less than 5, preferably less than 4, preferably less than 3, preferably less than 2, preferably less than 1.5.

[0047] Preferably, in particular when the aluminum source used in step a) is aluminum hydroxide, the pH of the mixture after addition of the base is greater than 9, preferably greater than 10, and preferably less than 13, preferably less than 12.

[0048] Preferably, the base does not contain the aluminum element.

[0049] Preferably, the base used is chosen from NaOH, LiOH, NH40H, KOH, Ca(OH)2, RbOH, CsOH, Sr(OH)2, Ba(OH)2, Mg(OH)2, and mixtures thereof. Preferably, the base is chosen from NaOH, LiOH, NH4OH, and mixtures thereof. Preferably, the base is LiOH.

[0050] Preferably, the agitation time is greater than 5 minutes, preferably greater than 10 minutes, preferably greater than 15 minutes, and preferably less than 5 hours.

[0051] Preferably, the mixture is kept agitated at a temperature above 15°C, preferably above or equal to 20°C, preferably above or equal to 25°C.

[0052] In one embodiment, steps a) and b) are carried out simultaneously.

[0053] In step c), a chlorine salt is added to the mixture, such that the ratio molar ratio between the Cl supplied by said chlorine salt and the Al present in the mixture, i.e. greater than 0.25, said mixture being kept agitated after introduction of said chlorine salt at a temperature below 50°C, said molar ratio between the Cl supplied by said chlorine salt and the Al present in the mixture being greater than or equal to 0.5, preferably greater than or equal to 1, preferably greater than 1, if the process does not include step f).

[0054] In one embodiment, the process includes step f).

[0055] Preferably, the molar ratio between the Cl supplied by said chlorine salt and the Al present in the mixture is greater than 0.25, preferably greater than 0.4, preferably greater than 0.5, and preferably less than 10, preferably less than 9, preferably less than 8, preferably less than 7, preferably less than 6, preferably less than 5, preferably less than 4, preferably less than 3, of preference less than 2, preferably less than 1.5.

[0056] Preferably the chlorine salt does not contain the element aluminium.

[0057] Preferably, the chlorine salt is selected from LiCl, NaCl, KCl, CaCl2, NH4Cl, MgCl2 and mixtures thereof. Preferably, the chlorine salt is LiCl.

[0058] Preferably, the agitation time is greater than 5 minutes, preferably greater than 10 minutes, preferably greater than 15 minutes, and preferably less than 48 hours.

[0059] Preferably, the mixture is kept agitated at a temperature above 15°C, preferably above or equal to 20°C, preferably above or equal to 25°C.

[0060] The base in step b), the chlorine salt in step c), and their respective quantities are chosen so as to provide an amount of lithium in the mixture such that the Li / Al molar ratio is greater than or equal to 1. Preferably, said molar ratio is greater than 1.1, preferably greater than 1.2, and preferably less than 4, preferably less than 2.

[0061] In one embodiment, steps a), b) and c) are carried out simultaneously.

[0062] In step d), the temperature of the mixture is increased to a temperature Ti greater than or equal to 50°C and less than or equal to 60°C, the time ti being the time during which said mixture is at a temperature greater than or equal to 50°C.

[0063] Preferably, the mixture is kept stirring during step d).

[0064] Preferably, the time ti is greater than 5 minutes, preferably greater than 10 minutes, and preferably less than 15 hours, preferably less than 10 hours.

[0065] In step e), the mixture is maintained at a temperature greater than or equal to 50°C and less than or equal to 60°C for a time t2.

[0066] Preferably, the mixture is kept agitated during step e).

[0067] Let T20 be the average temperature during step e)

[0068] Preferably, during step e), the temperature of the mixture is substantially constant and equal to T2b

[0069] Preferably, the time t2 is greater than 40 minutes, preferably greater than 45 minutes, preferably greater than 60 minutes, and preferably less than 10 hours, preferably less than 7 hours.

[0070] In step f), which is optional, an acid is added to the mixture while stirring so as to lower the pH of said mixture to a value less than or equal to 8, preferably less than or equal to 7.5, and preferably greater than or equal to 6, preferably greater than or equal to 6.5, the chlorine salt in step c), said acid, and their respective quantities being chosen so that the Cl / Al molar ratio in the mixture is greater than or equal to 1, preferably greater than 1, the mixture being maintained at a temperature less than or equal to 60°C, the time t3 being the time during which the mixture is at a temperature greater than or equal to 50°C.

[0071] In a preferred embodiment, at least part of the amount of Cl required to obtain a Cl / Al molar ratio greater than or equal to 1, preferably greater than 1, is supplied by said acid.

[0072] In one embodiment, several acids are added to the mixture. In this embodiment, one of the acids may contain Cl, preferably contains Cl.

[0073] Preferably the acid is chosen from HCl, H2SO4, HNO3, HI, HBr, HC1O4, HC1O3, HMnO4, H2MnO4 and mixtures thereof, preferably from HCl, HNO3, HBr, HC1O4, HC1O3 and mixtures thereof. Preferably the acid is HCl.

[0074] Preferably the Cl / Al molar ratio in the mixture is set to a value less than 3, preferably less than 2.

[0075] Let T30 be the average temperature during step f).

[0076] Preferably, during step f), the temperature of the mixture is substantially constant and equal to T3p

[0077] Preferably, the time t3 is greater than 5 minutes, preferably greater than 10 minutes, and preferably less than 60 minutes, preferably less than 40 minutes.

[0078] The implementation of step f) depends in particular on the nature of the lithium source from which lithium extraction is envisaged, especially its pH. By way of example, if said lithium source has a pH below 7, the process according to the invention preferably includes step f).

[0079] The mixing carried out in steps b), c), d), e) and possibly f) can be carried out according to any known technique, such as for example using a mixer or a grinder, preferably in a wet process with control and adjustment of the temperature of the mixture.

[0080] In step g), optional and preferred, the mixture is filtered to obtain a paste, said mixture being maintained at a temperature less than or equal to 60°C, time t4 being the time during which the mixture is at a temperature greater than or equal to 50°C.

[0081] T40 is called the average temperature of the mixture during the time t4.

[0082] Preferably, during step g), the temperature of the mixture during time t4 is substantially constant and equal to T4b

[0083] In one embodiment, the temperature of the mixture is lowered below 50°C before the start of filtration.

[0084] In a preferred embodiment, the time t4 is less than 15 minutes, preferably less than 10 minutes, preferably less than 5 minutes.

[0085] Any known filtration technique can be implemented during this step, in particular a filter press, a centrifuge, a belt filter, a drum filter.

[0086] At the end of step g), optional, the cumulative time ti+t2+t3+t4, or t5, during which the mixture has been exposed to a temperature greater than or equal to 50°C and less than or equal to 60°C is greater than or equal to 45 minutes and less than 15 hours.

[0087] Preferably, the time t5 is greater than 50 minutes, preferably greater than 55 minutes, preferably greater than 1 hour.

[0088] The time t5 is a function of the temperature and the median size of the aluminum source. A person skilled in the art knows how to adjust the time t5 according to the temperature and the median size of the aluminum source. For example, if the median size of the aluminum source is less than 1 pm, and if in step g), t4 is equal to 0, and if the temperature in steps d), e) and f) is equal to 50°C (in other words Ti=T2i=T3i=50°C), the time t5 is greater than 3 hours and less than 15 hours, preferably less than 10 hours, preferably less than 7 hours.For example, if the median size of the aluminum source is less than 1 pm, and if the temperature in steps d), e) and f) is equal to 60°C (in other words Ti=T2i=T3i= 60°C), and if preferably the time t4 is less than 15 minutes, preferably less than 10 minutes, preferably less than 5 minutes, the time t5 is greater than or equal to 45 minutes, preferably greater than 1 hour and less than 3 hours, preferably less than 2 hours, preferably less than 1.5 hours.

[0089] Preferably, time t5 is such that times tb, t2, t3 and t4 satisfy the following relations:

[0090] [1 / (-1.21 / +75)] + [t2 / (-l.2T20+75)] + [t3 / (-l.2T30+75)] + [t4 / (-l.2T40+75)] < 1 and [ / / (-0.2251^14.25)] + [t2 / (-0.225T20+14.25)] + [t3 / (-0.225T30+14.25)] + [t4 / (-0.225T40 + 14.25)] > 1.

[0091] Preferably, the time t5 is such that the times tb, t2, t3 and t4 satisfy the following relations:

[0092] [ / / (-0.81 / +50)] + [t2 / (-0.8T20+50)] + [t3 / (-0.8T30+50)] + [t4 / (-0.8T40+50)] < 1, of preference [1 / (-0.551^34.5)] + [t2 / (-0.55T20+34.5)] + [t3 / (-0.55T30+34.5)] + [t4 / (-0.55T 40+34.5)] < 1 and / or [1 / (-0.21^13)] + [t2 / (-0.2T20+13)] + [t3 / (-0.2T30+13)] + [t4 / (-0.2T40 +13)] > 1.

[0093] In one embodiment, the temperatures in steps d), e) and possibly f) are substantially constant and equal to Tb, T2i and T3b respectively, and time t5 is such that times tb, t2, t3 and t4 satisfy the following relationships:

[0094] [1 / (-1.21^75)] + [t2 / (-l.2T21+75)] + [t3 / (-l.2T31+75)] + [t4 / (-l.2T40+75)] < 1 and [ / / (-0.2251^14.25)] + [t / (-0.225T21+14.25)] + [t3 / (-0.225T31+14.25)] + [t4 / (-0.225T40 + 14.25)] > 1.

[0095] Preferably, in said embodiment, time t5 is such that times tb, t2, t3 and t4 satisfy the following relationships:

[0096] [t / (-0.8Ti+50)] + [t2 / (-0.8T21+50)] + [t3 / (-0.8T31+50)] + [t4 / (-0.8T40+50)] < 1, of preference [^ / (-0.551^+34.5)] + [t2 / (-0.55T21+34.5)] + [t3 / (-0.55T31+34.5)] + [t4 / (-0.55T 40+34.5)] < 1 and / or [1^(-0.21^13)3+^ / (-0.212^13)1+ [t3 / (-0.2T31+13)] + [t4 / (-0.2T40 +13)] > 1.

[0097] These relationships advantageously improve the lithium adsorption capacity of the product according to the invention.

[0098] In one embodiment, the temperature in steps d), e) and f) is equal to 60°C (in other words Ti=T2i=T3i=60°C), the time t4 being preferably less than 15 minutes, preferably less than 10 minutes, preferably less than 5 minutes, and the cumulative time ti+t2+t3+t4, in other words t5, the time during which the mixture has been exposed to a temperature greater than or equal to 50°C and less than or equal to 60°C is greater than or equal to 45 minutes, preferably greater than 1 hour and less than 3 hours, preferably less than 2 hours, preferably less than 1.5 hours.

[0099] In one embodiment, the temperature in steps d), e) and f) is equal to 50°C (in other words Ti=T2i=T3i=50°C), the time t4 is equal to 0, and the cumulative time ti+t2 +t3, in other words t5, the time during which the mixture has been exposed to a temperature equal to 50°C is greater than 3 hours and less than 15 hours, preferably less than 10 hours, preferably less than 7 hours.

[0100] In a preferred embodiment, the process according to the invention comprises, after step g), a step h) of shaping a starting charge comprising the paste obtained at the end of step g) into the form of an object or a coating, and an optional step i) of reducing the water content of said object.

[0101] In step h), a starting charge comprising the paste obtained at the end of step g) is shaped into the form of an object or a coating deposited on a support.

[0102] The shaping can be carried out according to any technique known to a person skilled in the art, for example extrusion, granulation, pressing, casting, atomization, screen printing, tape casting, or drip casting, in particular when an object is obtained, or by stamping, lamination, coating, granulation, in particular when a coating deposited on a support is obtained.

[0103] In one embodiment the starting charge does not include a binder.

[0104] In one embodiment, the starting material also comprises a binder, preferably a polysaccharide including a group capable of forming an ionic bond with a gelling agent for the formation of a gelled polysaccharide, in particular in an amount such that the mass ratio of the amount of said polysaccharide to the total amount of said polysaccharide and of the paste obtained at the end of step g), considered dry, is greater than or equal to 0.1% and less than or equal to 5%. Preferably, said mass ratio is greater than or equal to 0.2%, preferably on greater than or equal to 0.3%, and preferably less than or equal to 4%, preferably less than or equal to 3%, preferably less than or equal to 2%, preferably less than or equal to 1%.

[0105] Preferably, the polysaccharide group capable of forming an ionic bond with a gelling agent is a carboxylate group COO.

[0106] Preferably, the polysaccharide comprises a group capable of forming an ionic bond with a gelling agent selected from divalent cations, trivalent cations (for example, an Fe or Al cation) and mixtures thereof, preferably selected from alkaline earth cations, preferably selected from Ca, Sr, Ba, Mg cations and mixtures thereof. Preferably, the polysaccharide comprises a group capable of forming an ionic bond with a Ca cation.

[0107] Preferably, the polysaccharide comprising a group capable of forming an ionic bond with a gelling agent is chosen from alginates and pectins.

[0108] Preferably, the polysaccharide comprising a group capable of forming an ionic bond with a gelling agent is chosen from alginates, preferably from sodium alginates, potassium alginates, ammonium alginates, calcium alginates, and mixtures thereof. Preferably, the alginate is an ammonium alginate.

[0109] In the process according to the invention, the polysaccharide comprising a group capable of forming an ionic bond with a gelling agent, preferably alginate, can be supplied in the form of a solution.

[0110] As is well known to those skilled in the art, the starting charge may include, in addition to the paste obtained at the end of step g) and polysaccharide comprising a group capable of forming an ionic bond with a gelling agent, preferably an alginate, a solvent and / or a plasticizer and / or a lubricant, the natures and quantities of which are adapted to the shaping method of step h).

[0111] Preferably the solvent is water. The quantity of solvent is adapted to the shaping process implemented in step h) as well as to the presence of polysaccharide comprising a group capable of forming an ionic bond with a gelling agent in the starting feed.

[0112] In one embodiment, particularly when the starting charge contains an amount of solvent, preferably water, that is too large for the shaping process envisaged in step h), a step to remove part of the solvent may be carried out before step h).

[0113] In one embodiment, step f) makes it possible to obtain a paste having a solvent content, preferably water, adapted to the shaping process envisaged in step h).

[0114] The starting charge optionally contains a plasticizer.

[0115] Preferably, the plasticizer content is between 0.1% and 10%, preferably between 0.5% and 5%, preferably between 0.5% and 2%, by mass based on the mass of the paste obtained at the end of step g) of the starting load.

[0116] All plasticizers conventionally used for the manufacture of porous ceramic products can be used, for example polyethylene glycol, polyolefin oxides, hydrogenated oils, alcohols, in particular glycerol and glycol, esters, and mixtures thereof.

[0117] In a preferred embodiment, the starting charge does not contain plasticizers.

[0118] The starting feed optionally contains a lubricant. Preferably, the lubricant content is between 0.1% and 10%, preferably between 0.5% and 5%, preferably between 0.5% and 2%, by mass based on the mass of the paste obtained at the end of step g) of the starting feed.

[0119] All lubricants conventionally used for the manufacture of porous ceramic products can be used, for example petroleum jelly and / or glycerin and / or waxes.

[0120] The presence and nature of the lubricant and / or plasticizer depend in particular on the shaping technique used in step h).

[0121] In a preferred embodiment, the starting charge does not contain lubricants.

[0122] In a preferred embodiment, the starting charge contains no other constituents than the paste obtained at the end of step g), the binder, preferably a polysaccharide, and a solvent.

[0123] The mixing of the various components of the starting feed can be carried out using any technique known to those skilled in the art, for example in a mixer, preferably a high-intensity mixer or a Z-arm mixer, in a turbulate mixer, or in a jar mill with balls, preferably alumina balls. Preferably, the mixing is carried out in a high-intensity mixer or a Z-arm mixer.

[0124] The total mixing time is preferably more than 5 minutes, and preferably less than 30 minutes, preferably less than 20 minutes.

[0125] Step h) may be preceded by a step for removing at least part of the solvent, so as to adapt the quantity of solvent, preferably water, to the shaping technique envisaged in step h). All known techniques for removing at least part of a solvent, preferably water, may be used, preferably drying, preferably in air, at atmospheric pressure. Preferably, the maximum temperature reached during said drying is above 20°C, and preferably below 100°C.

[0126] The objects obtained after shaping can be in the form of cylinders, polylobates, rings, or spheres. Preferably, said objects have a largest dimension less than 100 mm, preferably less than 80 mm, preferably less than 50 mm, preferably less than 30 mm, or even less than 10 mm and preferably greater than 1 mm and / or a smallest dimension, measured in a plane perpendicular to the direction of the largest dimension, greater than 1 pm, or even greater than 10 pm (micrometers).

[0127] The coating obtained after shaping may have a thickness greater than 10 µm, preferably greater than 50 µm, preferably greater than 100 µm, preferably greater than 200 µm, and preferably less than 1 mm, preferably less than 500 µm. Preferably the substrate is made of a material selected from ceramics, metals, organic products, in particular polymers, and mixtures thereof.

[0128] A preferred embodiment will now be described. - In the preferred embodiment, at step h), the starting material contains a polysaccharide, preferably an alginate, and is shaped to obtain a preform, such shaping being carried out using any technique known to those skilled in the art, for example, extrusion, granulation, pressing, casting, atomization, screen printing, tape casting, or drip casting. Preferably in the embodiment, the shaping is carried out by screen printing. - Then, still according to this preferred embodiment, the preform is brought into contact with a solution comprising a gelling agent, capable of making the polysaccharide gel, preferably alginate.

[0129] The solution comprising a gelling agent suitable for gelling the polysaccharide, preferably alginate, is well known to those skilled in the art.

[0130] The gelling agent is preferably chosen from divalent cations, trivalent cations and mixtures thereof, preferably from alkaline earth cations, preferably from Ca, Sr, Ba, Mg cations and mixtures thereof. Preferably the gelling agent is a Ca cation.

[0131] The solution containing the gelling agent is preferably chosen from a solution comprising a divalent cation salt, a solution comprising a trivalent cation salt, or the lithium source from which the lithium is extracted, preferably brine, especially when it contains such a cation.

[0132] Preferably the solution comprising a divalent cation salt or a trivalent cation salt is chosen from a solution of iodide of said cation and / or a solution of chloride of said cation.

[0133] Preferably, the gelling solution is a solution comprising an alkali-earth cation iodide and / or an alkali-earth cation chloride. Even more preferably, the gelling solution is a solution comprising an alkali-earth cation chloride, preferably a solution comprising calcium chloride.

[0134] In a preferred embodiment, the gelling solution is the lithium source from which lithium is extracted, preferably the brine from which the lithium is to be captured, particularly when it includes a divalent and / or trivalent cation.

[0135] In another possible embodiment, the gelling solution is a calcium chloride solution, the concentration of which in calcium chloride is preferably greater than 1 mol / 1, preferably greater than 2 mol / 1 of solution. - The preform can be brought into contact with the gelling solution, for example, by immersing the preform in a bath of gelling solution or by spraying the preform with the gelling solution.

[0136] In one embodiment, the shaping and the contacting of the preform with the gelling solution are combined, in particular when the preform is implemented by drop-by-drop gelation.

[0137] In step i), which is optional and preferred, the water content of the object or coating obtained at the end of step h) is reduced.

[0138] This reduction in water content can be achieved by means of drying.

[0139] Preferably, the maximum temperature reached during said drying is greater than 20°C, and preferably less than 100°C, preferably less than 80°C, preferably less than 60°C.

[0140] Preferably, the drying cycle includes a plateau at the maximum temperature reached. The plateau holding time is preferably greater than 5 seconds and preferably less than 20 hours. Drying is preferably carried out in air, at atmospheric pressure.

[0141] Preferably, the water content of the product at the end of step i) is greater than 1%, preferably greater than 5%, preferably greater than 10% and preferably less than 60%, on the basis of the mass of the product.

[0142] In one embodiment, steps h) and i) can be carried out, at least partially, simultaneously.

[0143] The invention also relates to a product according to the invention obtained by the process according to the invention. Examples

[0144] The following non-limiting examples are given for the purpose of illustrating the invention.

[0145] The nature of the crystallized phases of the objects in the examples is determined by the following classical method:

[0146] The products in the examples are previously exposed to air for 170 hours at 25°C, at atmospheric pressure.

[0147] Acquisitions are performed using a Panalytical X'Pert type instrument equipped with a copper anode, over an angular range of 20° between 5° and 80°, with a step size of 0.017°, and a counting time of 300 s / step. The front optics include a fixed 0.25° divergence slit, a 0.02 rad Soller slit, a 10 mm mask, and a fixed 0.5° anti-scattering slit. The sample is rotated. The rear optics include a fixed 0.25° anti-scattering slit, a 0.02 rad Soller slit, and a nickel filter.

[0148] The diffraction patterns are then analyzed qualitatively using EVA software and the ICDD2016 database.

[0149] The PDF datasheet 00-031-0700 from the ICDD2016 database allows the phase (LiCl).2Al(OH)3, xH20 to be identified.

[0150] The crystallized phase of lithiated bayerite highlighted may exhibit a slight angular shift of the peaks compared to said data sheet, a consequence in particular of the amount of Li inserted in the structure of the lithiated bayerite.

[0151] The average size of the lithiated bayerite crystallites, D, of the products of the examples is classically determined by X-ray diffraction on a powder of said product, previously exposed to air for 170 hours at 25°C, at atmospheric pressure, using an X'Pert type apparatus from the Panalytical company, with the following Debye-Scherrer equation:

[0152] D = -^--x^x-^ cos# - K being equal to 0.89, - X being the wavelength of X-rays, here equal to that of copper, i.e. 1.54 Angstroms, - B being the full width at half maximum (FWHM) of the peak of the (003) plane of the lithia-treated bayerite (PDF datasheet 00-031-0700 from the ICCD database), in degrees, - b being the FWHM of the peak of the single-crystal silicon standard used, here measured as 0.05°, and - 20 being the angle of maximum intensity of the peak corresponding to the plane (003) of the lithia-rich bayerite, in degrees.

[0153] The acquisition of the diffraction patterns of the single-crystal silicon standard and of the example is carried out, over an angular range 20 between 5° and 80°, with a The step size is 0.017°, and the counting time is 300 s / step for the sample and 100 s / step for the single-crystal silicon standard. The front optics include a fixed 0.25° divergence slit, a 0.02 rad Soller slit, a 10 mm mask, and a fixed 0.5° anti-scatter slit. The sample is rotated. The rear optics include a fixed 0.25° anti-scatter slit, a 0.02 rad Soller slit, and a nickel filter.

[0154] After eliminating the Ka2 line, the full width at half maximum of the peaks is determined using the EVA software, and the average size of the lithiated bayerite crystallites is determined using the FWHM function.

[0155] The cumulative content of aluminum hydroxide and boehmite was determined using the same X-ray diffraction patterns used to identify the crystalline phases present. After eliminating the Ka2 line and using EVA software, it is possible to measure the area Aha of the aluminum hydroxide diffraction peak within an angular range of approximately 18.3°, the area ABo of the boehmite diffraction peak within an angular range of approximately 14°, and the area ABl of the lithia-bearing bayerite diffraction peak within an angular range of approximately 11.3°. The cumulative content of aluminum hydroxide and boehmite is then calculated according to formula (1) given previously:

[0156] T = 100* (Aha + Abo) / (Aha + AB0 + ABL) (1)

[0157] Thus, when the product does not contain aluminum hydroxide or boehmite, the cumulative level of aluminum hydroxide and boehmite is equal to 0.

[0158] With the exception of the elements O and H, the contents of the different elements present in the products of the examples are determined, on products dried under air at 200°C for 16 hours, at atmospheric pressure, by inductively coupled plasma spectrometry (or “ICP” in English).

[0159] The water content is determined as the mass loss, expressed as a percentage, after drying in air at 200°C for 16 hours, at atmospheric pressure. After such drying, the product is said to be "dry".

[0160] The content of elements other than H and O, partly Li, Cl and Al, is determined on the dry product by inductively coupled plasma spectrometry, using an Agilent 5800 ICP-OES instrument.

[0161] The median particle size of a powder or suspension is measured using a LA950V2 laser particle size analyzer marketed by Horiba. Manufacturing protocol

[0162] The following raw materials were used for the examples. - A gibbsite A1(OH)3 powder, with a median size of 1.6 pm, a purity greater than 99.5% by mass and a specific surface area of ​​5 m2 / g, for examples 1 to 5, - Lithium hydroxide monohydrate (LiOH,H2O), with a purity greater than 99.5% by mass, for examples 2 to 5, - Lithium chloride (LiCl), with a purity greater than 99.5% by mass, for examples 1 to 5, - Hydrochloric acid (HCl), with a purity greater than 99% by mass, in a 16M aqueous solution, for examples 2 to 5, - An ammonium alginate of purity greater than 99% by mass, for examples 2 to 5.

[0163] The product of Example 1, outside the scope of the invention and in accordance with the teachings of US4,348,295, is the product of Example 1 of US4,348,295 and was obtained in the following manner:

[0164] 50g of gibbsite are added to 200 ml of a 20% wt. LiCl solution, then the The resulting mixture is stirred for 2 hours at 115°C.

[0165] The resulting mixture is filtered on a Buchner, at room temperature (below 50°C), with filter papers of permeability equal to 2 pm in order to obtain a paste.

[0166] The products of examples 2 to 5 were obtained in the following manner:

[0167] In step a), for each example, 500 g of aluminum hydroxide are added to 2000 g of water, at a temperature of 25°C, in a LabStar mill marketed by Netzsch and ground for 75 minutes. At the end of step a), the aluminum hydroxide suspended in the water has a median size of 0.55 pm.

[0168] In step b), for each example, (LiOH, H2O) is added to the mixture obtained at the end of step a), such that the molar ratio between the OH supplied by (LiOH, H2O) and the Ai initially present in the mixture is as described in Table 1. For each example, the temperature at which this step took place, the mixing time and the pH of the mixture measured at the end of this step are also described in Table 1.

[0169] In step c), for each example, LiCl is added to the mixture obtained at the end of step b), so that the molar ratio between the Cl supplied by LiCl and the Ai initially present in the mixture is as described in Table 1. For each example, the temperature at which this step took place and the mixing time are described in Table 1.

[0170] At the end of step c), the amount of lithium in the mixture, expressed by the Li / Al molar ratio, is as described in Table 1.

[0171] In step d), the mixture is heated using a hot plate to a temperature Ti, the time ti being the time during which the mixture is at a temperature greater than or equal to 50°C. Table 1 describes the temperature Ti and the time tb for each example.

[0172] In step e), for each example, the mixture is maintained at a constant temperature T2i for a time t2. Table 1 describes the temperature T2i and the time t2 for each example.

[0173] In step f), for each example, HCl is added to the mixture obtained at the end of step e), so that the pH of the mixture is lowered to the value indicated in Table 1, the value of the Cl / Al molar ratio in the mixture after the addition of HCl being as described in Table 1, the introduction of the acid being carried out at a temperature equal to T3, which is kept constant during step f), the time t3 being the time during which the mixture is at a temperature greater than or equal to 50°C. T3i and t3 are described in Table 1.

[0174] In step g), for each example, the mixture is filtered using a Buchner funnel at room temperature (below 50°C) with filter papers having a permeability of 2 pm to obtain a paste. The time t4 during which the mixture is at a temperature greater than or equal to 50°C is described in Table 1.

[0175] The time t5, equal to the sum of the times ti+t2+t3+t4, is also described, for each example, in Table 1.

[0176] The following table 1 summarizes the parameters used in the manufacturing steps of examples 2 to 5.

[0177] [Tables] Example 2 Example 3 Example 4 (*) Example 5 Step b), quantity of LiOH,H2O added, in g 134.15 134.15 134.15 134.15 Step b), OH / Al molar ratio 0.5 0.5 0.5 0.5 Temperature at which step b took place 25°C 25°C 25°C 25°C Step b), mixing time 15 min 5 min 15 min 15 min Step c), Cl / Al molar ratio 1 1 1 1 Temperature at which step c took place 25°C 25°C 25°C 25°C Step c), mixing time 15 min 37 min 15 min 15 min Li / Al molar ratio in the mixture at the end of step c) 1.5 1.5 1.5 Step d), temperature Ti 50°C 60°C 60°C 60°C Step d), time ti 0 min 15 min 15 min 15 min Step e), temperature T2i 50°C 60°C 60°C 60°C Step e), time t2 4 h 45 min 45 min 10 min 20 min Step f), pH after adding HCl 3 3 3 3 Step f), molar ratio Cl / Al after adding HCl 1.6 1.6 1.6 1.6 Step f), temperature T3i 50°C 60°C 60°C 60°C Step f), time t3 15 min 15 min 5 min 5 min Step g), time t4 0 5 min 5 min 5 min Time t5 = ti + t2 + t3 + t4 5 h 1 h 20 35 min 45 min

[0178] (*) : not an invention

[0179] The different pastes obtained have the characteristics shown in the table 2 next.

[0180] [Tables2] Example 1(*) Example 2 Example 3 Example 4 (*) Example 5 Quantity of water, as a mass percentage 60% 60% 65% 65% 70% Average size of lithiased bayerite crystallites (nm) 55 15.4 16.8 18.2 17.3 Crystalline phases identified Lithiased bayerite Lithiased bayerite Lithiased bayerite Lithiased bayerite, gibbsite Lithiased bayerite, gibbsite Cumulative content of aluminum hydroxide and boehmite (%) Not determined 0 0 30 10 Chemical analysis by inductively coupled plasma spectrometry, after drying in air at 200°C for 16 hours, at atmospheric pressure, as a weight percentage Li content (%) 4.31 4.21 3.83 3.13 4.23 Cl content (%) 22.02 21.51 19.56 15.99 21.61 Al content (%) 21.1 19.1 21.9 20.5 20.3 Content of elements other than Li, Al, Cl, O and H (%) 0.1 0.1 0.1 0.1 0.1 Elements O and H (%) Complement to 100 Complement to 100 Complement to 100 Complement to 100 Complement to 100

[0181] (*) : not an invention

[0182] The products of examples 2 and 3 consist of more than 99% by mass of water, lithiated bayerite, and LiCl.

[0183] The products of examples 4 and 5 consist of more than 99% by mass of water, lithiated bayerite, gibbsite and LiCl.

[0184] For each example, the resulting dough was then shaped as follows.

[0185] For example 1, the paste obtained after filtration was spread on a metal grid The material, 1 mm thick and perforated with circular holes 1.5 mm in diameter, is then scraped with a spatula on both sides of the grid so that the paste fills the holes. The grid is then said to be "loaded." Once loaded, the grid is placed under a flow of hot air at 60°C, which allows the grid to be "unloaded," with the formed objects falling into a container placed beneath the grid. These objects are in the form of cylinders with an average length of 0.8 mm and an average diameter of 1.4 mm.

[0186] For examples 2 to 5, in step h), a starting charge consisting of the paste obtained at the end of step g) and ammonium alginate was produced, the content of said alginate being equal to 1% by mass on the basis of the mass of the starting charge after drying at 200°C for 16 hours, at atmospheric pressure.

[0187] Said paste and ammonium alginate were mixed in a planetary mixer under hot air created by a heat gun set to a temperature of 100°C, for 120 minutes in order to obtain a homogeneous starting charge and having a water content compatible with the shaping technique.

[0188] The initial charge was then spread onto a metal grid 1 mm thick and perforated with circular holes 1.5 mm in diameter. The grid was then scraped with a spatula on both sides so that the initial charge filled the holes. The grid is then said to be "loaded". Once loaded, the grid is placed under a flow of hot air at 60°C, which allows the grid to be "unloaded," with the formed objects falling into a container placed beneath the grid. These objects are in the form of cylinders with an average length of 0.8 mm and an average diameter of 1.4 mm.

[0189] Examples 2 and 3, according to the invention, exhibit a high lithium adsorption capacity.

[0190] The shaped objects of Examples 2 and 3, according to the invention, exhibit a higher lithium adsorption capacity than that of Example 1, in accordance with the prior art. This comparison also highlights the importance of limiting the temperature to 60°C during the product manufacturing process.

[0191] A comparison of Example 4, outside the invention, and Example 3, according to the invention, shows that in Example 4, a time t5, time during which the mixture is at a temperature greater than or equal to 50°C, equal to 35 minutes for a temperature at step e) of 60°C leads to a product having a cumulative rate of aluminium hydroxide and boehmite equal to 30%, which limits its lithium adsorption capacity.

[0192] Of course, the invention is not limited to the embodiments described, which are provided for illustrative purposes only.

Claims

Demands

1. Product comprising: - water, and - crystallites, at least a part, preferably all, of said crystallites being made up of lithiased bayerite, the average size of the lithiased bayerite crystallites being greater than or equal to 10 nm and less than or equal to 25 nm, and said product having a cumulative content of aluminium hydroxide and boehmite less than or equal to 10%, said product comprising at least the elements Li, Cl, Al, O and H, the elements Li, Cl and Al being present, in said dry product in the following amounts, determined by inductively coupled plasma spectrometry and in weight percentages: - 2% < Li < 5%, - 10% < Cl < 26%, - 15% < Al < 30%.

2. Product according to the preceding claim having the following chemical analysis, determined on the dry product by inductively coupled plasma spectroscopy, in weight percentage: - 2% < Li < 5%, - 10% < Cl < 26%, - 15% < Al < 30%, - elements other than Li, Cl, Al, O and H: < 3%, - O and H: complement to 100%.

3. A product according to any one of the preceding claims, wherein: - the water content is greater than 1% and less than 95%, and / or - the average size of the lithiated bayerite crystallites is less than 23 nm

4. Product according to any one of the preceding claims wherein: - the cumulative content of aluminium hydroxide and boehmite is less than or equal to 8%, and / or - the crystallized phases comprise lithiated bayerite, boehmite and / or aluminium hydroxide selected from gibbsite, bayerite, doyleite, nordstrandite and mixtures thereof.

5. Product according to claim 3 or 4 wherein: - the water content is greater than 5%, and / or - the water content is less than 80%, and / or - the crystallized phases include lithiated bayerite and an aluminium hydroxide chosen from gibbsite, bayerite, doyleite, nord-strandite and their mixtures.

6. Product according to the preceding claim in which: - the water content is greater than 10%, and / or - the water content is less than 70%, and / or - the only crystallized phase is lithia-treated bayerite.

7. Product according to any one of the preceding claims, consisting of at least 80% by mass of water, and lithiated bayerite crystallites, and aluminium hydroxide and / or boehmite, and LiCl, and a binder.

8. Product according to the preceding claim, consisting of at least 80%, by mass, of water, and lithiated bayerite crystallites, and aluminium hydroxide, and LiCl, and a binder.

9. Product according to the preceding claim, consisting of at least 80% by mass in total of water, lithiated bayerite crystallites, LiCl and a binder.

10. Product according to one of the three immediately preceding claims wherein the binder is a polysaccharide, preferably an alginate.

11. A method for manufacturing a product according to any one of the preceding claims comprising the following steps: a. Suspension in aqueous solution of an aluminum source, preferably a single aluminum source, selected from boehmite or aluminum hydroxide and mixtures thereof, preferably aluminum hydroxide, grinding said aqueous suspension to obtain a median size less than or equal to 3 pm if the median size of the aluminum source is greater than 3 pm, said suspension being maintained during this step a) at a temperature below 50°C; b. Increasing the pH by adding a base, such that the molar ratio between the OH provided by said base and the Ai present in the mixture is greater than 0.20, said mixture being kept stirred after introduction of said base, at a temperature below 50°C; c.Addition of a chlorine salt, such that the molar ratio between the Cl supplied by said chlorine salt and the Ai present in the mixture is greater than 0.25, said mixture. being kept in agitation after introduction of said chlorine salt at a temperature below 50°C; the base in step b), the chlorine salt in step c) and their respective quantities being chosen so as to provide an amount of lithium in the mixture such that the Li / Al molar ratio is greater than or equal to 1; d. Raising the temperature of the mixture to a temperature greater than or equal to 50°C and less than or equal to 60°C, the time ti being the time during which said mixture is at a temperature greater than or equal to 50°C; e. Maintaining the mixture at a temperature greater than or equal to 50°C and less than or equal to 60°C for a time t2; f. Optionally, adding an acid to the mixture, under stirring, so as to decrease the pH of the mixture to a value less than or equal to 8, the chlorine salt in step c), said acid, and their respective quantities being chosen so that the molar ratio Cl / Al in the mixture is greater than or equal to 1, the mixture being maintained at a temperature less than or equal to 60°C, time t3 being the time during which the mixture is at a temperature greater than or equal to 50°C, the molar ratio between the Cl supplied by the chlorine salt and the Ai present in the mixture being greater than or equal to 0.5 if the process does not include said step f); g. Optionally, and preferably, filtering the mixture to obtain a paste, the mixture being maintained at a temperature less than or equal to 60°C, time t4 being the time during which the mixture is at a temperature greater than or equal to 50°C; the cumulative time ti+t2+t3+t4 = t5 being greater than or equal to 45 minutes and less than 15 hours.

12. A method for manufacturing a product according to the preceding claim, wherein in step a) the aqueous suspension of an aluminum source selected from boehmite or aluminum hydroxide and mixtures thereof is ground to obtain a median size < 1 pm.

13. A method according to any one of claims 11 to 12, wherein the time t5 is such that the times tb, t2, t3, and t4 satisfy the following relationships: [tb / (-1,2T1 + 75)] + [t2 / (-1,2T20 + 75)] + [t3 / (-1,2T30 + 75)] + [t4 / (-1,2T40 + 75)] < 1 and [tb / (-0.2251 + 14.25)] + [t2 / (-0.225T20 + 14.25)] + [t3 / (-0.225T30 + 14.25)] + [tb / (-0.2250 + 14.25)] > 1, where Ti is the temperature reached by the mixture at step d), T20 is the average temperature during step e), T30 is the average temperature during step f), and T40 is the average temperature of the mixture during time t4.

14. A method according to the preceding claim, wherein the time t5 is such that the times tb, t2, t3, and t4 satisfy the following relationships: [t1 / (-0.8T1 + 50)] + [t2 / (-0.8T20 + 50)] + [t3 / (-0.8T30 + 50)] + [t4 / (-0.8T40 + 50)] < 1, and / or - the time t5 is such that the times tb, t2, t3, and t4 satisfy the following relationship: [t1 / (-0.21t1 + 13)] + [t2 / (-0.2T20 + 13)] + [t3 / (-0.2T30 + 13)] + [t4 / (-0.2T40 + 13)] > 1

15. A method according to the preceding claim, wherein the time t5 is such that the times tb t2, t3 and t4 satisfy the following relation: [ti / (-0.55Ti +34.5)] + [t2 / (-0.55T20+34.5)] + [t3 / (-0.55T30+34.5)] + [t4 / (-0.55T40 +34.5)] < 1.

16. A process according to any one of claims 11 to 15 wherein: - aluminium hydroxide, boehmite and mixtures thereof are the only aluminium sources used in all steps of said process, and / or - in step b), the molar ratio between the OH supplied by the base and the Ai present in the mixture is greater than 0.25 and less than 10, and / or - in step b), the pH of the mixture after addition of the base is greater than 9 and less than 13.

17. A method according to any one of claims 11 to 16 wherein: - in step c), the molar ratio between the Cl supplied by the chlorine salt and the Al present in the mixture is less than 10, and / or - the base in step b), the chlorine salt in step c), and their respective quantities are chosen so as to supply an amount of lithium in the mixture such that the Li / Al molar ratio is greater than 1.1 and less than 4, and / or - in step d), the time ti is greater than 5 minutes.

18. A process according to any one of claims 11 to 17 wherein: - in step e), the temperature of the mixture is substantially constant, and / or - in step e), the time t2 is greater than 40 minutes, and / or - in optional step f), at least a portion of the quantity of Cl ne- necessary to obtain a Cl / Al molar ratio greater than 1 is provided by the acid.

19. A method according to any one of claims 11 to 18 wherein: - in optional step f), the pH of the mixture is reduced to a value less than 7.5 and greater than 6.5, and / or - in optional step f), the Cl / Al molar ratio in the mixture is set to a value less than 3, and / or - in optional step f), the temperature of the mixture is substantially constant.

20. A method according to any one of claims 12 to 19 wherein: - at optional step f), time t3 is greater than 5 minutes, and / or - at step g), time t4 is less than 15 minutes.

21. A process according to claim 16, wherein aluminium hydroxide is the only source of aluminium used in all the steps of said process.

22. A method according to any one of claims 11 to 21, wherein - steps a) and b) are carried out simultaneously, and / or - steps a), b) and c) are carried out simultaneously.

23. A method according to any one of claims 11 to 22, comprising, after step g), a step h) of shaping a starting charge comprising the paste obtained at the end of step g), in the form of an object or a coating, preferably in the form of an object, and an optional step i) of reducing the water content of said object or said coating.

24. Method according to the preceding claim wherein in step h), the starting charge comprises a binder.

25. A method according to the preceding claim wherein the binder is a polysaccharide comprising a group capable of forming an ionic bond with a gelling agent for the formation of a gelled polysaccharide.

26. A method according to the preceding claim in which the polysaccharide is selected from alginates.

27. ​​A method according to any one of claims 23 to 26, wherein steps h) and i) are carried out, at least partially, simultaneously.

28. Lithium capture device, comprising a product according to any one of claims 1 to 10 or a product obtained by a process according to any one of claims 11 to 27.