Product containing lithiated bayerite and process for producing such a product

Abstract

The present invention relates to a product comprising: - water, and - crystallites, at least some, preferably substantially all of said crystallites consisting 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 content of aluminium hydroxide and boehmite of 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 contents, determined by inductively coupled plasma mass spectrometry, in percentages by weight: - 2% < Li < 5%, - 10% < Cl < 26%, - 15% < Al < 30%.

Description

[0001] DESCRIPTION

[0002] TITLE: Product comprising lithiated bayerite and method of manufacturing such a product

[0003] Technical field

[0004] The present invention relates to a product comprising lithiated bayerite and to a method of manufacturing a product comprising lithiated bayerite.

[0005] Prior art

[0006] The use of lithium, particularly in batteries, is constantly increasing.

[0007] Brines are sources of lithium, for which lithium extraction is necessary.

[0008] 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. The lithium is then recovered by passing an aqueous solution through these columns. The result is a concentrated lithium solution which will be purified before a precipitation step, generally in the form of lithium carbonate.

[0009] Lithium adsorbents, in particular lithiated bayerite, are materials advantageously used as active material allowing the production of concentrated lithium solution within extraction columns.

[0010] FR3053264 describes a process for preparing a crystalline solid material of formula (LiCI) x .2AI(OH)3, nH2O with x between 0.4 and 1 and n between 0.01 and 10.

[0011] US4,348,295 describes a method for manufacturing LiX.2AI(OH)3, nH2O, X being an anion forming an acid in molecular combination with H or forming a salt in combination with a metal ion, said method comprising a step of reacting a hydrated alumina with a concentrated solution of LiX at a temperature above 85°C. However, the material obtained by this method has a limited lithium adsorption capacity.

[0012] There is a need for a method for manufacturing a product comprising lithiated bayerite, and which makes it possible to obtain a product having a high lithium adsorption capacity. The aim of the invention is to satisfy this need.

[0013] Statement of the invention

[0014] According to the invention, this aim is achieved by means of a product comprising, and preferably essentially consisting of:

[0015] - water, and

[0016] - crystallites, at least a portion, preferably substantially all, of said crystallites consisting 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 content of aluminum 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 contents, 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 lithiated bayerite crystallites and the cumulative content of aluminum hydroxide and boehmite are measured on the said product after exposure to air for 170 hours at 25°C, at atmospheric pressure.

[0021] The said dry product is obtained after drying in 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:

[0023] - the product has the following chemical analysis, determined on the dry product by inductively coupled plasma spectrometry, in weight percentages:

[0024] Li in a content greater than 2% and less than 5%, and

[0025] - Cl in a content greater than 10% and less than 26%, and

[0026] - Al in a content greater than 15% and less than 30%, and Elements other than Li, Cl, Al, O and H in a content less than 3%, and

[0027] - O and H in a content corresponding to the complement at 100%;

[0028] - the average size of lithiated bayerite crystallites less than 23 nm;

[0029] - the water content is greater than 1%, preferably greater than 5%, preferably greater than 10% and / or preferably less than 95%, preferably less than 80%, preferably less than 70%; the cumulative rate of aluminum hydroxide and boehmite is less than or equal to 8%, preferably less than or equal to 5%;

[0030] - the crystallized phases of the product comprise lithiated bayerite, boehmite and / or an aluminum hydroxide chosen from gibbsite, bayerite, doyleite, nordstrandite and mixtures thereof, preferably the crystallized phases of the product comprise lithiated bayerite and an aluminum hydroxide chosen from gibbsite, bayerite, doyleite, nordstrandite and mixtures thereof;

[0031] - the only crystallized phase present in the product is lithiated bayerite; - the product consists of at least 80%, by mass, water and crystallites of lithiated bayerite, and aluminum hydroxide and / or boehmite, and LiCI, and a binder, preferably the product consists of at least 80%, by mass, water and crystallites of lithiated bayerite, and aluminum hydroxide, and LiCI, and a binder, preferably the product consists of at least 80%, by mass, water and crystallites of lithiated bayerite, and LiCI, and a binder, said binder preferably being a polysaccharide, preferably an alginate.

[0032] The invention also relates to a method for manufacturing a product according to the invention and as previously described, comprising the following steps: a) Aqueous suspension of an aluminum source, preferably a single aluminum source, chosen from a boehmite or an aluminum hydroxide and their mixtures, preferably an aluminum hydroxide, grinding of said aqueous suspension so as to obtain a median size less than or equal to 3 μm if the median size of said aluminum source is greater than 3 μm, 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 stirring after introduction of said base, at a temperature below 50°C;c) Adding a chlorine salt, such that the molar ratio between the Cl provided by said chlorine salt and the Al present in the mixture is greater than 0.25, said mixture being kept stirring 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 a quantity 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, with stirring, so as to reduce 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, the 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 provided by the chlorine salt and the Al 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 so as to obtain a paste, the mixture being maintained at a temperature less than or equal to 60°C, the 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.;

[0033] According to preferred but non-limiting embodiments of the present invention, which may, where appropriate, be combined with each other:

[0034] Step a) comprises the implementation of grinding of the aqueous suspension of an aluminum source chosen from a boehmite or an aluminum hydroxide and their mixtures, so as to obtain a median size < 1 pm;

[0035] - time t5 is such that times ti, t2, t3 and t4 satisfy the following relations: [ti / (- 1 ,2Ti+75)] + [t2 / (-1 ,2T 20 +75)] + [t3 / (-1 ,2T 30 +75)] + [t4 / (-1 ,2T 40 +75)] < 1, preferably [ti / (-0.8Ti+50)] + [t2 / (-0.8T 20 +50)] + [t3 / (-0.8T 30 +50)] + [t4 / (-0.8T 40 +50)] < 1, preferably [ti / (-0.55Ti+34.5)] + [t2 / (-0.55T 20 +34.5)] + [t3 / (-0.55T 30 +34.5)] + [t4 / (- 0.55T 40+34.5)] < 1, and [ti / (-0.225Ti+14.25)] + [t2 / (-0.225T 20 +14.25)] + [t3 / (- 0.225T 30 +14.25)] + [t4 / (-0.225T 40 +14.25)] > 1, preferably [ti / (-0.2Ti+13)] + [t2 / (- 0.2T 20 +13)] + [t3 / (-0.2T 30 +13)] + [t4 / (-0.2T 40 +13)] > 1 , with Ti being the temperature reached by the mixture in step d), T 20 being the average temperature during step e), T 30 being the average temperature during step f), T 40being the average temperature of the mixture during time t4; aluminum hydroxide, boehmite and their mixtures are the only sources of aluminum used in all the steps of the process, preferably aluminum hydroxide is the only source of aluminum used in all the steps 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 addition of the base is greater than 9 and less than 13; in step c), the molar ratio between the Cl provided 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 a quantity of lithium in the mixture such that the Li / AI molar ratio is greater than 1.1 and less than 4; in step d), the time ti is greater than 5 minutes;in step e), the temperature of the mixture is substantially constant; in step e), the time t2 is greater than 40 minutes;

[0036] - in optional step f), at least part of the quantity of Cl necessary to obtain a CI / AI molar ratio greater than or equal to 1 is provided by the acid;

[0037] - in optional step f), the pH of the mixture is reduced to a value less than 7.5, and greater than 6.5;

[0038] - in optional step f), the CI / AI molar ratio in the mixture is set to a value less than 3;

[0039] - in optional step f), the temperature of the mixture is substantially constant;

[0040] - in optional step f), time t3 is greater than 5 minutes;

[0041] - in step g), the time t4 is less than 15 minutes;

[0042] - steps a) and b) are carried out simultaneously;

[0043] - steps a), b) and c) are carried out simultaneously; the method comprises, 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;

[0044] - in step h), the starting charge comprises 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 chosen from alginates;

[0045] - steps h) and i) are carried out, at least partially, simultaneously.

[0046] 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 previously.

[0047] Definitions

[0048] - The term "lithia bayerite" refers to the compound with the formula LiCI.2AI(OH)3.xH2O as indicated in the ICDD PDF 00-031 -0700, but also by extension, to compounds with a ratio of the molar quantities of lithium and aluminum, Li / AI, different from 0.5. In certain modes, it may be less than 0.5. In other modes, it may be greater than 0.5.

[0049] - The compound with the formula AI(OH)3 is called "aluminum hydroxide". Gibbsite, bayerite, doyleite and nordstrandite are aluminum hydroxides.

[0050] - The compound with the formula y-AIO(OH) is called “boehmite”.

[0051] - The “cumulative rate of aluminum hydroxide and boehmite”, in %, in a product, is calculated according to the following formula (1):

[0052] T = 100* (AHA + ABO) / (AHA + ABO + ABL) (1) where

[0053] - AHA is the sum of the areas of the aluminum hydroxide phases, measured on an X-ray diffraction diagram of said product, for example obtained from a device of the X'Pert diffractometer type from the company Panalytical, equipped with a copper DX tube, without deconvolution treatment, after having eliminated the Ka2 line. The area of ​​an aluminum hydroxide phase is that of its diffraction peak located in an angular domain 29 substantially equal to 18.3°;

[0054] ABO is the area of ​​the diffraction peak of boehmite located in an angular domain 29 approximately equal to 14°, measured on the same diagram, without deconvolution treatment, after eliminating the Ka2 line;

[0055] - ABL is the area of ​​the diffraction peak of the (993) plane of lithiated bayerite located in an angular domain 29 substantially equal to 11.3°, measured on the same diagram, without deconvolution treatment, after eliminating the Ka2 line.

[0056] - According to the classical definition, "polysaccharides" are polymers composed of chains of osidic units linked by glycosidic bonds.

[0057] - A "gellable polysaccharide" under the action of a gelling agent is a polysaccharide capable of forming a gel under the action of said gelling agent.

[0058] - A gelled polysaccharide results from the association of polysaccharide chains under the action of a gelling agent. For example, alginate has the formula (CsHyOe^n. Alginate is a polysaccharide chain comprising carboxylate groups COO-. Calcium ions Ca 2+(gelling agent) react with two strands of alginate, i.e. with the carboxylate groups COO-, leading to the polymerization of the alginate chains and the bonding of the molecules together. The reaction thus allows the creation of a gel.

[0059] - “Dry product” means a product obtained after drying in air at 299°C for 16 hours (at atmospheric pressure), this drying being, for example, conventionally carried out in an oven.

[0060] - The term "median size" of a powder of particles or a suspension of particles is used to refer to the size dividing said particles of the powder or suspension into first and second populations of equal mass, these first and second populations comprising only particles having 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 granulometer.

[0061] All percentages in this description are percentages by mass unless otherwise stated.

[0062] The verbs “contain,” “include,” and “present” should be interpreted broadly, without limitation, unless otherwise indicated. Detailed description

[0063] A product according to the invention has one or more of the following optional characteristics:

[0064] 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 loss of mass, expressed as a percentage, after drying at 200°C for 16 hours in air, at atmospheric pressure;

[0065] An average size of lithiated bayerite crystallites less than 23 nm, preferably less than 20 nm;

[0066] A cumulative rate of aluminum hydroxide and boehmite less than or equal to 8%, preferably less than or equal to 5%, preferably substantially zero;

[0067] The crystallized phases comprise, preferably consist of lithiated bayerite, boehmite and / or an aluminum hydroxide selected from gibbsite, bayerite, doyleite, nordstrandite and mixtures thereof, preferably gibbsite. Preferably, the crystallized phases comprise, preferably consist of lithiated bayerite and an aluminum hydroxide selected from gibbsite, bayerite, doyleite, nordstrandite and mixtures thereof, preferably gibbsite. Preferably, the only crystallized phase is lithiated bayerite. The determination of the crystallized phases, the determination of the cumulative content of 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;

[0068] - 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 contents, in weight percentages:

[0069] Li: preferably greater than 2.5%, preferably greater than 3%, and / or preferably less than 4.5%, preferably less than 4%, and

[0070] - Cl: preferably greater than 11%, preferably greater than 13% and / or preferably less than 24%, preferably less than 22%, and

[0071] Al: preferably greater than 17%, preferably greater than 19% and / or preferably less than 28%, preferably less than 26%;

[0072] - 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

[0073] - 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

[0074] - 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

[0075] 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

[0076] - O and H in a content corresponding to the complement at 100%;

[0077] - After drying in air at 200°C for 16 hours, at atmospheric pressure, the product has a Li / AI mass ratio greater than 0.1, preferably greater than 0.15 and / or preferably less than 0.3, preferably less than 0.25;

[0078] - After drying in air at 200°C for 16 hours, at atmospheric pressure, the product has a Li / CI 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, for 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 LiCI, 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 aluminum 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;.

[0079] The product is in the form of objects having the shape of cylinders, polylobes, 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 1 pm, or even greater than 10 pm (micrometers);

[0080] The product is in the form of a coating deposited on a support. 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 support is made of a material chosen from ceramics, metals, organic products, in particular polymers, and mixtures thereof;

[0081] 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 of 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%, 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 be, for example, detected by size exclusion chromatography.

[0082] A product according to the invention may be manufactured according to a method according to the invention comprising steps a) to g), in particular and preferably steps a) to i) mentioned above.

[0083] In step a), an aluminum source chosen from a boehmite or an aluminum hydroxide and their mixtures, preferably an aluminum hydroxide, is placed in aqueous suspension, and 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, said suspension being maintained during this step a) at a temperature below 50°C. The aqueous suspension of the aluminum source and the grinding of said aqueous suspension can be carried out simultaneously.

[0084] 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.

[0085] In a preferred embodiment, an aqueous suspension of an aluminum source selected from boehmite or aluminum hydroxide and mixtures thereof, preferably aluminum hydroxide, is ground to obtain a median size < 1 pm, said suspension being maintained during this step at a temperature below 50°C. Preferably the aluminum hydroxide is gibbsite.

[0086] Preferably, aluminum hydroxide, boehmite and their mixtures 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.

[0087] Preferably, the median size obtained after grinding is less than or equal to 0.7 μm, preferably less than or equal to 0.5 μm.

[0088] Preferably, the suspension is maintained during step a) at a temperature above 15°C, preferably above or equal to 20°C.

[0089] The grinding can be carried out using any technique known to those skilled in the art, such as wet grinding.

[0090] In step b), the pH of the mixture obtained at the end of step a) is increased by the addition of 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 stirring after introduction of said base, at a temperature below 50°C.

[0091] Preferably, the molar ratio between the OH provided 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.

[0092] Preferably, particularly when the source of aluminum used in step a) is an 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.

[0093] Preferably, the base does not contain the aluminum element.

[0094] More preferably, the base used is chosen from NaOH, LiOH, NH4OH, 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.

[0095] Preferably, the stirring time is greater than 5 minutes, preferably greater than 10 minutes, preferably greater than 15 minutes, and preferably less than 5 hours.

[0096] Preferably, the mixture is kept stirring at a temperature above 15°C, preferably above or equal to 20°C, preferably above or equal to 25°C.

[0097] In one embodiment, steps a) and b) are performed simultaneously.

[0098] In step c), a chlorine salt is added to the mixture, such that the molar ratio between the Cl provided by said chlorine salt and the AI ​​present in the mixture is greater than 0.25, said mixture being kept stirring after introduction of said chlorine salt at a temperature below 50°C, said molar ratio between the Cl provided by said chlorine salt and the AI ​​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).

[0099] In one embodiment, the method comprises step f).

[0100] Preferably, the molar ratio between the Cl provided by said chlorine salt and the AI ​​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, preferably less than 2, preferably less than 1.5.

[0101] Preferably the chlorine salt does not contain the element aluminum.

[0102] More preferably, the chlorine salt is chosen from LiCI, NaCI, KCI, CaCI2, NH4CI, MgCI2 and their mixtures, preferably chosen from LiCI, NaCI, KCI, CaCI2 and their mixtures. Preferably the chlorine salt is LiCI.

[0103] Preferably, the stirring time is greater than 5 minutes, preferably greater than 10 minutes, preferably greater than 15 minutes, and preferably less than 48 hours.

[0104] Preferably, the mixture is kept stirring at a temperature above 15°C, preferably above or equal to 20°C, preferably above or equal to 25°C.

[0105] The base in step b), the chlorine salt in step c), and their respective quantities are chosen so as to provide a quantity 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.

[0106] In one embodiment, steps a), b) and c) are performed simultaneously.

[0107] 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.

[0108] Preferably, the mixture is kept stirring during step d).

[0109] 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.

[0110] 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.

[0111] Preferably, the mixture is kept stirring during step e).

[0112] Let T 20 , the average temperature during step e)

[0113] Preferably, during step e), the temperature of the mixture is substantially constant and equal to T2I.

[0114] 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. In step f), optional, an acid is added to the mixture with stirring so as to reduce 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 amounts being chosen so that the CI / AI 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.

[0115] In a preferred embodiment, at least part of the quantity of Cl necessary to obtain a CI / AI molar ratio greater than or equal to 1, preferably greater than 1, is provided by said acid.

[0116] In one embodiment, multiple acids are added to the mixture. In this embodiment, one of the acids may comprise Cl, preferably comprises Cl.

[0117] Preferably the acid is selected from HCl, H2SO4, HNO3, HI, HBr, HCIO4, HCIO3, HMnO4, H2MnO4 and mixtures thereof, preferably from HCl, HNO3, HBr, HCIO4, HCIO3 and mixtures thereof. Preferably the acid is HCl.

[0118] Preferably the CI / AI molar ratio in the mixture is set to a value less than 3, preferably less than 2.

[0119] Let T 30 , the average temperature during step f).

[0120] Preferably, during step f), the temperature of the mixture is substantially constant and equal to T31.

[0121] 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.

[0122] The implementation of step f) depends in particular on the nature of the lithium source for which the extraction of lithium is envisaged, in particular its pH. For example, if said lithium source has a pH of less than 7, the method according to the invention preferably comprises step f).

[0123] The mixture produced in steps b), c), d), e) and possibly f) can be produced using any known technique, such as for example using a mixer or a grinder, preferably using a wet process with control and adjustment of the temperature of the mixture.

[0124] In step g), optional and preferred, the mixture is filtered so as to obtain a paste, said mixture being maintained at a temperature less than or equal to 60°C, the time t4 being the time during which the mixture is at a temperature greater than or equal to 50°C.

[0125] We call T4o the average temperature of the mixture during time t4.

[0126] Preferably, during step g), the temperature of the mixture during time t4 is substantially constant and equal to T41. In one embodiment, the temperature of the mixture is lowered below 50°C before the start of filtration.

[0127] In a preferred embodiment, the time t4 is less than 15 minutes, preferably less than 10 minutes, preferably less than 5 minutes.

[0128] Any known filtration technique can be implemented during this stage, in particular a filter press, a centrifuge, a belt filter, a drum filter.

[0129] At the end of step g), optional, the cumulative time ti+t2+t 3+ t4, or t5, time during which the mixture was 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.

[0130] Preferably, the time t5 is greater than 50 minutes, preferably greater than 55 minutes, preferably greater than 1 hour.

[0131] 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 as a function of the temperature and the median size of the aluminum source. For example, if the median size of the aluminum source is less than 1 μm, 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 t4is less than 15 minutes, preferably less than 10 minutes, preferably less than 5 minutes, the time t5is 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.

[0132] Preferably the time t5 is such that the times ti, t2, t3 and t4 satisfy the following relations: [ti / (-1,2Ti+75)] + [t2 / (-1,2T 20 +75)] + [t3 / (-1 ,2T 30 +75)] + [t4 / (-1 ,2T 40 +75)] < 1 and [ti / (- 0.225Ti+14.25)] + [t2 / (-0.225T 20 +14.25)] + [t3 / (-0.225T 30 +14.25)] + [t4 / (-0.225T 40 +14.25)] > 1. Preferably again the time t5 is such that the times ti, t2, t3 and t4 satisfy the following relations:

[0133] [ti / (-0.8Ti+50)] + [t2 / (-0.8T 20 +50)] + [t3 / (-0.8T 30 +50)] + [t4 / (-0.8T 40 +50)] < 1, preferably [ti / (- 0.55Ti+34.5)] + [t2 / (-0.55T 20 +34.5)] + [t3 / (-0.55T 30 +34.5)] + [t4 / (-0.55T 40 +34.5)] < 1 and / or [ti / (- 0.2Ti+13)] + [t2 / (-0.2T 20 +13)] + [t3 / (-0.2T 30 +13)] + [t4 / (-0.2T 40 +13)] > 1.

[0134] In one embodiment, the temperatures in steps d), e) and optionally f) are substantially constant and equal to Ti, T21 and T3I, respectively, and the time t5 is such that the times ti, t2, t3 and t4 satisfy the following relationships:

[0135] [ti / (-1,2Ti+75)] + [t2 / (-1,2T2I+75)] + [t3 / (-1,2T3I+75)] + [t4 / (-1,2T 40 +75)] < 1 and [ti / (- 0.225Ti+14.25)] + [t2 / (-0.225T2i+14.25)] + [t3 / (-0.225T3n-14.25)] + [t4 / (-0.225T 40+14.25)] > 1. Preferably, in said embodiment, the time t5 is such that the times ti, t2, t3 and t4 satisfy the following relationships:

[0136] [ti / (-0.8Ti+50)] + [t2 / (-0.8T2i+50)] + [t3 / (-0.8T3i+50)] + [t4 / (-0.8T 40 +50)] < 1, preferably [ti / (- 0.55Ti+34.5)] + [t2 / (-0.55T2i+34.5)] + [t3 / (-0.55T3i+34.5)] + [t4 / (-0.55T 40 +34.5)] < 1 and / or [ti / (- 0.2Ti+13)]+[t2 / (-0.2T2i+13)]+ [t3 / (-0.2T3i+13)] + [t4 / (-0.2T 40 +13)] > 1.

[0137] These relationships advantageously make it possible to improve the lithium adsorption capacity of the product according to the invention.

[0138] In one embodiment, the temperature in steps d), e) and f) is equal to 60°C (i.e. Ti=T2i=T3i=60 qC), 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, time during which the mixture was 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.

[0139] 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, time during which the mixture was 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.

[0140] In a preferred embodiment, the method 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) in the form of an object or a coating, and an optional step i) of reducing the water content of said object.

[0141] In step h), a starting charge comprising the paste obtained at the end of step g) is shaped into an object or a coating deposited on a support.

[0142] The shaping can be 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, in particular when an object is obtained, or by stamping, lamination, coating, granulation, in particular when a coating deposited on a support is obtained.

[0143] In one embodiment, the starting charge does not include a binder.

[0144] In one embodiment, the starting charge also comprises 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, 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 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%.

[0145] Preferably, the group of the polysaccharide capable of forming an ionic bond with a gelling agent is a carboxylate group COO-.

[0146] Preferably, the polysaccharide comprises a group capable of forming an ionic bond with a gelling agent chosen from divalent cations, trivalent cations (for example a cation of Fe or Al) and mixtures thereof, preferably chosen from alkaline earth cations, preferably chosen from cations of Ca, Sr, Ba, Mg and mixtures thereof. Preferably, the polysaccharide comprises a group capable of forming an ionic bond with a cation of Ca.

[0147] Preferably, the polysaccharide comprising a group capable of forming an ionic bond with a gelling agent is chosen from alginates and pectins.

[0148] 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 from sodium alginates, potassium alginates, ammonium alginates, and mixtures thereof. Preferably, the alginate is an ammonium alginate.

[0149] In the method according to the invention, the polysaccharide comprising a group capable of forming an ionic bond with a gelling agent, preferably alginate, can be provided in the form of a solution.

[0150] As is well known to those skilled in the art, the starting charge may comprise, in addition to the paste obtained at the end of step g) and the 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).

[0151] Preferably the solvent is water. The amount 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 charge.

[0152] In one embodiment, in particular when the starting charge contains a quantity of solvent, preferably water, which is too high with respect to the shaping process envisaged in step h), a step of removing part of the solvent may be carried out, before step h). In one embodiment, step f) makes it possible to obtain a paste having a solvent content, preferably water, suitable for the shaping process envisaged in step h).

[0153] The starting charge optionally contains a plasticizer.

[0154] 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 charge.

[0155] 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 their mixtures.

[0156] In a preferred embodiment, the feedstock does not contain plasticizers.

[0157] The feedstock 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 feedstock.

[0158] All lubricants conventionally used for the manufacture of porous ceramic products can be used, for example petroleum jelly and / or glycerin and / or waxes.

[0159] The presence and nature of the lubricant and / or plasticizer depend in particular on the shaping technique used in step h).

[0160] In a preferred embodiment, the feedstock does not contain lubricants.

[0161] In a preferred embodiment, the starting charge does not contain any other constituents than the paste obtained at the end of step g), the binder, preferably a polysaccharide, and a solvent. The mixing of the different constituents of the starting charge can be carried out according to any technique known to those skilled in the art, for example in a mixer, preferably in a high-intensity mixer or in a Z-arm mixer, in a turbulator, in a jar mill with balls, preferably alumina balls. Preferably, the mixing is carried out in a high-intensity mixer or in a Z-arm mixer.

[0162] The total mixing time is preferably greater than 5 minutes, and preferably less than 30 minutes, preferably less than 20 minutes.

[0163] Step h) may be preceded by a step of 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 greater than 20°C, and preferably less than 100°C.

[0164] The objects obtained after shaping may be in the form of cylinders, polylobes, rings, or spheres. Preferably, said objects have a largest dimension of 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, of greater than 1 μm, or even greater than 10 μm (micrometers).

[0165] 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 support is made of a material chosen from ceramics, metals, organic products, in particular polymers, and their mixtures.

[0166] A preferred embodiment will now be described.

[0167] In said preferred embodiment, in step h), the starting charge contains a polysaccharide, preferably an alginate, and is shaped so as to obtain a preform, said shaping being carried out according to 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 said embodiment, the shaping is carried out by screen printing.

[0168] Then, still according to this preferred embodiment, the preform is brought into contact with a solution comprising a gelling agent, capable of gelling the polysaccharide, preferably alginate.

[0169] The solution comprising a gelling agent capable of gelling the polysaccharide, preferably alginate, is well known to those skilled in the art.

[0170] The gelling agent is preferably chosen from divalent cations, trivalent cations and mixtures thereof, preferably chosen from alkaline earth cations, preferably chosen from Ca, Sr, Ba, Mg cations and mixtures thereof. Preferably the gelling agent is a Ca cation.

[0171] The solution containing the gelling agent is preferably selected 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, particularly when it contains such a cation. Preferably the solution comprising a divalent cation salt or a trivalent cation salt is selected from an iodide solution of said cation and / or a chloride solution of said cation.

[0172] Preferably, the gelling solution is a solution comprising an alkaline earth cation iodide and / or an alkaline earth cation chloride. More preferably, the gelling solution is a solution comprising an alkaline earth cation chloride, preferably a solution comprising calcium chloride.

[0173] In a preferred embodiment, the gelling solution is the lithium source from which the lithium is extracted, preferably the brine from which the lithium is to be captured, especially when it comprises a divalent and / or trivalent cation.

[0174] In another possible embodiment, the gelling solution is a calcium chloride solution, the calcium chloride concentration of which is preferably greater than 1 mol / l, preferably greater than 2 mol / l of solution.

[0175] The preform may 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.

[0176] 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 gelling.

[0177] In step i), optional and preferred, the water content of the object or coating obtained at the end of step h) is reduced.

[0178] This reduction in water content can be achieved by drying.

[0179] 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.

[0180] More preferably, the drying cycle has a plateau at said maximum temperature reached. The holding time at the plateau is preferably greater than 5 seconds and preferably less than 20 hours. Drying is preferably carried out in air, at atmospheric pressure.

[0181] 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%, based on the mass of the product.

[0182] In one embodiment, steps h) and i) can be carried out, at least partially simultaneously.

[0183] The invention also relates to a product according to the invention obtained by the process according to the invention. Examples

[0184] The following non-limiting examples are given for the purpose of illustrating the invention.

[0185] The nature of the crystallized phases of the objects in the examples is determined by the following classical method:

[0186] The products of the examples are previously exposed to air for 170 hours at 25°C, at atmospheric pressure.

[0187] Acquisitions are carried out using an X'Pert type device from Panalytical, equipped with a copper anode, over an angular range 20 between 5° and 80°, with a step of 0.017°, and a counting time of 300 s / step. The front optics have a fixed divergence slit of 0.25°, a Soller slit of 0.02 rad, a 10 mm mask and a fixed anti-scattering slit of 0.5°. The sample is rotated on itself. The rear optics have a fixed anti-scattering slit of 0.25°, a Soller slit of 0.02 rad and a nickel filter.

[0188] The diffraction patterns are then qualitatively analyzed using EVA software and the ICDD2016 database.

[0189] The PDF data sheet 00-031-0700 from the ICDD2016 database allows the identification of the phase (LiCI).2AI(OH)3, xH2O.

[0190] The crystallized phase of lithiated bayerite highlighted may present a slight angular shift of the peaks compared to the said data sheet, in particular a consequence of the quantity of Li inserted into the structure of the lithiated bayerite.

[0191] The average size of the lithiated bayerite crystallites, D, of the products of the examples is conventionally 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 device from the company Panalytical, using the following Debye-Scherrer equation:

[0192] KX 1 180

[0193] D = — - x — x -

[0194] V(B 2 - & 2 ) cos 0 10 ™

[0195] K being equal to 0.89,

[0196] A being the wavelength of the X-rays, here equal to that of copper, i.e. 1.54 Angstrom, B being the width at half-maximum of the peak of the (003) plane of lithiated bayerite (PDF data sheet 00-031-0700 of the ICCD database), in degrees, b being the width at half-maximum of the peak of the monocrystalline silicon standard used, here measured equal to 0.05°, and

[0197] 20 being the angle of the maximum intensity of the peak corresponding to the (003) plane of the lithiated bayerite, in degrees. The acquisition of the diffraction patterns of the monocrystalline silicon standard and the example is carried out, over an angular range 29 between 5° and 80°, with a step of 0.017°, and a counting time of 300 s / step for the example and 100 s / step for the monocrystalline silicon standard. The front optics have a fixed divergence slit of 0.25°, a Soller slit of 0.02 rad, a 10 mm mask and a fixed anti-scattering slit of 0.5°. The sample is rotated on itself. The rear optics have a fixed anti-scattering slit of 0.25°, a Soller slit of 0.02 rad and a nickel filter.

[0198] After removing the Ka2 line, the full width at half maximum of the peaks is determined using EVA software, and the average size of the lithiated bayerite crystallites is determined using the FWHM function.

[0199] The determination of the cumulative rate of aluminum hydroxide and boehmite was carried out from the same X-ray diffraction diagrams used for the detection of the crystallized phases present. After eliminating the Ka2 line and using the EVA software, it is possible to measure the AHA area of ​​the aluminum hydroxide diffraction peak present in an angular range 29 substantially equal to 18.3°, the ABO area of ​​the boehmite diffraction peak located in an angular range 29 substantially equal to 14°, and the ABL area of ​​the lithiated bayerite diffraction peak located in an angular range 29 substantially equal to 11.3°. The cumulative rate of aluminum hydroxide and boehmite is then calculated according to the formula (1) given previously:

[0200] T = 1 9* (AHA + ABO) / (AHA + ABO + ABL) (1)

[0201] Thus, when the product does not contain aluminum hydroxide or boehmite, the cumulative rate of aluminum hydroxide and boehmite is equal to 9.

[0202] With the exception of the elements O and H, the contents of the various elements present in the products of the examples are determined, on products dried in air at 29°C for 16 hours, at atmospheric pressure, by inductively coupled plasma spectrometry (or "ICP" in English).

[0203] The water content is determined as the mass loss, expressed as a percentage, after drying in air at 299°C for 16 hours at atmospheric pressure. After such drying, the product is said to be "dry".

[0204] 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 5899 ICP-OES device.

[0205] The median size of a powder or suspension is measured using a laser granulometer model LA959V2 marketed by Horiba.

[0206] Manufacturing protocol

[0207] The following raw materials were used for the examples. A gibbsite powder AI(OH)3, having a median size equal to 1.6 pm, a purity greater than 99.5% by mass and a specific surface area equal to 5 m 2 / g, for examples 1 to 5,

[0208] Lithium hydroxide monohydrate (LiOH,H2O), with a purity greater than 99.5% by mass, for examples 2 to 5,

[0209] Lithium chloride LiCl, with a purity greater than 99.5% by mass, for examples 1 to 5,

[0210] Hydrochloric acid HCl, of purity greater than 99% by mass, in 16M aqueous solution, for examples 2 to 5,

[0211] An ammonium alginate of purity greater than 99% by mass, for examples 2 to 5.

[0212] The product of Example 1, outside the invention and in accordance with the teaching of US4,348,295, is the product of Example 1 of US 4,348,295 and was obtained in the following manner:

[0213] 50g of gibbsite are added to 200ml of a 20% by mass LiCl solution, then the resulting mixture is stirred for 2 hours at 115°C.

[0214] The mixture obtained is filtered on a Büchner funnel, at room temperature (below 50°C), with filter papers with a permeability equal to 2 pm in order to obtain a paste.

[0215] The products of Examples 2 to 5 were obtained as follows:

[0216] In step a), for each example, 500 g of aluminum hydroxide are added to 2000 g of water, at a temperature equal to 25°C, in a LabStar mill marketed by the company Netzsch and ground for 75 minutes. At the end of step a), the aluminum hydroxide suspended in the water has a median size equal to 0.55 pm.

[0217] In step b), for each example, (LiOH, H2O) is added to the mixture obtained at the end of step a), so that the molar ratio between the OH provided 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.

[0218] 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 provided 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.

[0219] At the end of step c), the quantity of lithium in the mixture, expressed by the molar ratio Li / Al is as described in table 1. In step d), the mixture is heated using a heating plate, to a temperature Ti, the time ti being the time during which said mixture is at a temperature greater than or equal to 50°C. Table 1 describes for each example the temperature Ti and the time ti.

[0220] In step e), for each example, the mixture is maintained at a constant temperature T21 for a time t2. Table 1 describes for each example the temperature T21 and the time t2.

[0221] 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 molar ratio CI / AI in the mixture after addition of HCl being as described in Table 1, the introduction of the acid taking place at a temperature equal to T3I 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. T31 and t3 are described in Table 1.

[0222] In step g), for each example, the mixture is filtered on a Büchner funnel, at room temperature (less than 50 °C), with filter papers with a permeability equal to 2 pm so as 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.

[0223] The time t5, equal to the sum of the times ti+t2+t3+t4, is also described, for each example, in table 1.

[0224] The following Table 1 summarizes the parameters used in the manufacturing steps of Examples 2 to 5.

[0225] [Table 1]

[0226] (*): excluding invention

[0227] The different pastes obtained have the characteristics shown in Table 2 below. [Table 2]

[0228] (*): excluding invention

[0229] The products of Examples 2 and 3 consist of more than 99% by mass of water, lithiated bayerite, and LiCI. The products of Examples 4 and 5 consist of more than 99% by mass of water, lithiated bayerite, gibbsite, and LiCI.

[0230] For each example, the resulting paste was then shaped as follows.

[0231] For example 1, the paste obtained after filtration was spread on a metal grid with a thickness equal to 1 mm and perforated with circular holes with a diameter equal to 1.5 mm, then scraped using a spatula on each side of the grid so that said paste fills the holes in said grid. The grid is then said to be "loaded". Once the grid is loaded, it is placed under a circulation of hot air at 60°C, which makes it possible to "unload" said grid, the objects formed falling into a container placed under the grid. Said objects obtained are in the form of cylinders with an average length equal to 0.8 mm and an average diameter equal to 1.4 mm.

[0232] 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 based on the mass of the starting charge after drying at 200°C for 16 hours, at atmospheric pressure.

[0233] The said paste and the ammonium alginate were mixed in a planetary mixer under hot air created by a heat gun set at a temperature equal to 100°C, for 120 minutes so as to obtain a homogeneous starting charge with a water content compatible with the shaping technique.

[0234] The starting charge was then spread on a metal grid of thickness equal to 1 mm and perforated with circular holes of diameter equal to 1.5 mm, then scraped using a spatula on each side of the grid so that said starting charge filled the holes of said grid. The grid is then said to be "charged". Once the grid is charged, it is placed under a circulation of hot air at 60°C, which makes it possible to "unload" said grid, the objects formed falling into a container placed under the grid. Said objects obtained are in the form of cylinders of average length equal to 0.8 mm and average diameter equal to 1.4 mm.

[0235] Examples 2 and 3, according to the invention, have a high lithium adsorption capacity. The shaped objects of Examples 2 and 3, according to the invention, have a lithium adsorption capacity greater 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.

[0236] 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 in step e) of 60°C leads to a product having a cumulative rate of aluminum hydroxide and boehmite equal to 30%, which limits its lithium adsorption capacity.

[0237] Of course, the invention is not limited to the embodiments described, provided only for illustration purposes.

Claims

DEMANDS 1. Product includes: - water, and - crystallites, at least a part, preferably all of said crystallites being composed 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 as 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. A product according to any one of the preceding claims, wherein: - the combined level of aluminium hydroxide and boehmite is less than or equal to 8%, and / or - the crystallized phases include lithiated bayerite, boehmite and / or an aluminium hydroxide selected from gibbsite, bayerite, doyleite, nordstrandite and their mixtures.

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 lithia-treated bayerite and an aluminum hydroxide selected from gibbsite, bayerite, doyleite, nordstrandite and mixtures thereof.

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

7. Product according to any one of the preceding claims, consisting of at least 80% by mass of water, and crystallites of lithiated bayerite, 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 crystallites of lithiated bayerite, 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.

1. A method for manufacturing a product according to any one of the preceding claims comprising the following steps: a) Suspension of an aluminum source, preferably a single aluminum source, selected from boehmite or aluminum hydroxide and mixtures thereof, preferably aluminum hydroxide, into an 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) Increase of the pH by the addition of 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 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 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 / AI molar ratio is greater than or equal to; 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 Al 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 t1, t2, t3 and t4 satisfy the following relations: [t1 / (-1, 2T1 + 75)] + [t2 / (-1, 2T1)] 20 +75)] + [t3 / (-1 ,2T 30 +75)] + [t4 / (-1, 2T 40 +75)] < 1 and [ti / (-0.225Ti+14.25)] + [t2 / (-0.225T 20 +14.25)] + [t3 / (-0.225T 30 +14.25)] + [t4 / (-0.225T 40 + 14.25)] > 1, with Ti being the temperature reached by the mixture in step d), T 20 being the average temperature during step e), T 30being the average temperature during step f), T 40 being 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 ti, t2, t3 and t4 satisfy the following relations: [ti / (-0.8Ti+50)] + [t2 / (-0.8T 20 +50)] + [t3 / (-0.8T 30 +50)] + [t4 / (-0.8T 40 +50)] < 1 , and / or - time t5 is such that times ti, t2, t3 and t4 satisfy the following relation: [ti / (-0.2Ti+13)] + [t2 / (-0.2T 20 +13)] + [t3 / (-0.2T 30 +13)] + [t4 / (-0.2T 40 +13)] > 1 A method according to the preceding claim, wherein the time t5 is such that the times ti, t2, t3 and t4 satisfy the following relation: [ti / (-0.55Ti+34.5)] + [t2 / (-0.55T2O+34.5)] + [t3 / (-0.55T 30 +34.5)] + [t4 / (-0.55T4o+34.5)] < 1. A method according to any one of claims 11 to 15 wherein: - aluminum hydroxide, boehmite and mixtures thereof are the only sources of aluminum used in all stages of said process, and / or - 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, and / or - in step b), the pH of the mixture after the addition of the base is greater than 9 and less than 13. A process 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 AI ​​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 provide 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 - at step d), the time ti is greater than 5 minutes. A method according to any one of claims 11 to 17, wherein: - at step e), the temperature of the mixture is substantially constant, and / or - at step e), the time t2 is greater than 40 minutes, and / or - in optional step f), at least part of the amount of Cl required to obtain a Cl / Al molar ratio greater than 1 is supplied by the acid. A process according to any one of claims 11 to 18, wherein: - in optional step f), the pH of the mixture is decreased to a value less than 7.5 and greater than 6.5, and / or - in optional step f), the CI / AI molar ratio in the mixture is set to a value less than 3, and / or - In the optional step f), the temperature of the mixture is substantially constant. A method according to any one of claims 12 to 19, wherein: - in optional step f), the time t3 is greater than 5 minutes, and / or - in step g), the time t4 is less than 15 minutes. A process according to claim 16, wherein aluminum hydroxide is the only source of aluminum used in all steps of said process. A process 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 in which 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. A 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.

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