Shaped lithium adsorbent particles and separation methods based thereon

Abstract

A shaped lithium adsorbent particle comprising a first major surface defined by a first perimeter having at least three edges, a second major surface defined by a second perimeter having the same number of edges as the first perimeter, and a peripheral surface comprising a plurality of walls disposed between the first and second major surfaces. The peripheral surface intersects the edges of the first and second perimeters and the average radius of curvature at the intersections is no greater than 50 micrometers. The length of the particle is no greater than 5 millimeters and the length of the particle is at least 2 times greater than the thickness of the particle. The lithium adsorbent shaped particle comprises a lithium adsorbent material.

Description

SHAPED LITHIUM ADSORBENT PARTICLES AND SEPARATION METHODS BASED THEREON Background

[0001] Chromatographic techniques are used in a variety of industries to extract or isolate chemical species of interest from a multicomponent system. Such techniques typically comprise a mobile phase containing the chemical species of interest and a stationary phase which selectively interacts with the chemical species of interest, thus isolating it from the mobile phase. The nature of that interaction varies depending upon the type of chromatography (e.g., adsorption, partition, ion exchange, size exclusion, etc.).

[0002] A common chromatographic set-up includes a mobile phase comprising the chemical species of interest and a packed bed of solid particles for the stationary phase. For example, the solid particles can be packed into a column that allows the mobile phase to flow through the column of solid particles under gravitational force, separating the chemical species of interest from the rest of the mobile phase. The chemical species of interest can then be removed from the stationary phase by washing the solid particles with a separate solution that extracts the chemical species of interest into the wash and out the column.

[0003] Chromatographic techniques are currently being explored for the extraction of lithium salt from various brines (e.g., continental, geothermal, oilfield, etc.). Lithium is a highly sought after element for its use in a variety of industrial sectors including energy, electronics, automobile, and aerospace. However, lithium is typically found in low concentrations within salt brines that make its recovery challenging. One active area of interest is the use of lithium-aluminum layered double hydroxide (LDH) as a stationary phase to chromatographically separate lithium ions from the brine. Efficient and effective ways to carryout chromatographic separations on industrially large scales, as would be required in direct lithium extraction, are of current interest. Summary

[0004] Chromatographic techniques using solid particles as a stationary phase desire to maximize the interaction between the solid particles and species of interest in the mobile phase. This is typically accomplished by maximizing the surface area (i.e., small particles) and increasing the packing efficiency (i.e., density of particles). Suitable particles include crushed particles and multimodal spherically-shaped particles that can densely pack together. However, such dense packing can also create back pressure within the stationary phase leading to long flow times which dramatically decreases separation efficiency. Other ways of expressing a lower flow rate are in terms of a higher pressure drop across the column or a lower permeability of the column. One solution to address the back pressure is to use larger diameter columns to contain the solid particles, but this can dramatically increase the overall cost of the process.

[0005] The present disclosure provides shaped lithium adsorbent particles that are specifically shaped to exhibit sufficient volumetric surface area to affect separation of the species of interest from themobile phase while also lowering packing densities within the stationary phase to reduce back pressure relative to other particles having similar volumetric surface area.

[0006] In one embodiment, the present disclosure provides a shaped lithium adsorbent particle comprising: a first major surface defined by a first perimeter having at least three edges; a second major surface defined by a second perimeter having the same number of edges as the first perimeter, the second major surface spatially separated from the first major surface and having the same shape as the first major surface; and a peripheral surface comprising a plurality of walls disposed between the first and second major surfaces, the peripheral surface having the same number of walls as the first perimeter has edges, the peripheral surface contiguous with all edges of the first and second perimeters, wherein the peripheral surface intersects the edges of the first and second perimeters and the average radius of curvature at the intersections is no greater than 50 micrometers, wherein the length of the particle is no greater than 5 mm, wherein the length of the particle is at least 2 times greater than the thickness of the particle, and wherein the lithium adsorbent shaped particle comprises a lithium adsorbent material.

[0007] In another embodiment, the present disclosure provides a method of making the above- mentioned shaped lithium adsorbent particles, the method comprising adding a lithium adsorbent dispersion to a mold having one or more shaped cavities, drying the lithium adsorbent dispersion to form shaped lithium adsorbent particles, and removing the shaped lithium adsorbent particles from the mold.

[0008] In yet another embodiment, the present disclosure provides a device comprising a reservoir having a fluid inlet and a fluid outlet, and a plurality of the above-mentioned shaped lithium adsorbent particles disposed within the reservoir.

[0009] In a further embodiment, the present disclosure provides a method of separating lithium ions from an aqueous solution comprising disposing the above-mentioned shaped lithium adsorbent particles in a reservoir having a fluid inlet and a fluid outlet, contacting a solution comprising lithium ion with the shaped lithium adsorbent particles in the reservoir, and separating at least a portion of the lithium ion from the solution.

[0010] The above summary of the present disclosure is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The description that follows more particularly exemplifies illustrative embodiments. Brief Description of Drawings

[0011] FIG.1 is a schematic cross-sectional view of one embodiment of a separation device according to the present disclosure;

[0012] FIG.2 is a schematic perspective view of an exemplary shaped lithium adsorbent particle according to the present disclosure;

[0013] FIG 3 is a schematic perspective view of another exemplary shaped lithium adsorbent particle according to the present disclosure;

[0014] FIG.4A-4C are schematic top views of other exemplary shaped lithium adsorbent particles according to the present disclosure;

[0015] FIG.5A-5D are schematic top views of various corners showing how to calculate the interior angle (^) of a corner according to the present disclosure;

[0016] FIG.6A-6B are schematic cross-sectional views of the radius of curvature for an edge of an exemplary shaped lithium adsorbent particle according to the present disclosure;

[0017] FIG.7 is a schematic cutaway perspective view of an exemplary mold useful in making shaped lithium adsorbent particles according to the present disclosure;

[0018] FIGS.8A-8B are optical images of the shaped alumina particles 1 (SAP1) used in Examples 1-4 according to the present disclosure;

[0019] FIGS.9A-9B are optical images of the shaped alumina particles 2 (SAP2) used in Examples 5-8 according to the present disclosure;

[0020] FIGS.10A-10D are schematic perspective views of the geometric shapes used in the numerical simulations according to Examples 22, 23, 24 and Comparative Example 8, respectively, according to the present disclosure;

[0021] FIG.11 is a simulated image of the packing configuration of shaped particles in Example 23 after completion of simulation step (1) according to the present disclosure;

[0022] FIG.12 is a plot of permeability versus volumetric surface area for various geometric shapes used in the packed bed simulations, according to the present disclosure; and

[0023] FIG.13 is a plot of porosity versus geometric shapes used in the packed bed simulations, according to the present disclosure.

[0024] With reference to the figures, like reference numbers offset by multiples of 100 (e.g., 210, 310, 510a, 510b, and 510c) indicate like elements. Unless otherwise indicated, all figures and drawings in this document are not to scale and are chosen for the purpose of illustrating different embodiments of the invention. In particular, the dimensions of the various components are depicted in illustrative terms only, and no relationship between the dimensions of the various components should be inferred from the drawings, unless so indicated. Detailed Description

[0025] In the following description of illustrative embodiments, reference is made to the accompanying figures of the drawing which form a part hereof, and in which are shown, by way of illustration, specific embodiments. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.

[0026] As used herein:

[0027] The term “comprises” and variations thereof do not have a limiting meaning where these terms appear in the description and claims. Such terms will be understood to imply the inclusion of a stated step or element or group of steps or elements but not the exclusion of any other step or element or group of steps or elements. By “consisting of” is meant including, and limited to, whatever follows the phrase “consisting of.” Thus, the phrase “consisting of” indicates that the listed elements are required or mandatory, and that no other elements may be present. By “consisting essentially of” is meant includingany elements listed after the phrase, and limited to other elements that do not interfere with or contribute to the activity or action specified in the disclosure for the listed elements. Thus, the phrase “consisting essentially of” indicates that the listed elements are required or mandatory, but that other elements are optional and may or may not be present depending upon whether or not they materially affect the activity or action of the listed elements.

[0028] The terms “a,” “an,” and “the” are used interchangeably with “at least one” to mean one or more of the components being described.

[0029] The term “and / or” means one or all of the listed elements or a combination of any two or more of the listed elements.

[0030] The term “some embodiments” means that a particular feature, configuration, composition, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. Thus, the appearances of such phrases in various places throughout this specification are not necessarily referring to the same embodiment of the disclosure. Furthermore, the particular features, configurations, compositions, or characteristics may be combined in any suitable manner in one or more embodiments.

[0031] The terms “preferred” and “preferably” refer to embodiments of the disclosure that may afford certain benefits, under certain circumstances; however, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the disclosure.

[0032] All numbers are assumed to be modified by the term “about”. As used herein in connection with a measured quantity, the term “about” refers to that variation in the measured quantity as would be expected by the skilled artisan making the measurement and exercising a level of care commensurate with the objective of the measurement and the precision of the measuring equipment used.

[0033] The recitations of numerical ranges by endpoints include all numbers subsumed within that range as well as the endpoints (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.). The phrase “up to” a number (e.g., up to 50) includes the number (e.g., 50).

[0034] The term "perimeter" refers to a closed boundary of a surface, which may be a planar surface, or a non-planar surface.

[0035] The term "interior angle" refers to an angle, within the perimeter, defined by two adjacent edges of the perimeter.

[0036] The shaped lithium adsorbent particles disclosed here are designed to enhance the volumetric surface area (i.e., surface area to volume ratio) of the particles while reducing the potential pressure drop across the reservoir. For purposes of brevity, the terms “shaped lithium adsorbent particles” and “shaped particles” are used interchangeably herein. In one exemplary embodiment illustrated in FIG.2, the shaped particles 200 comprise a first major surface 210 defined by a first perimeter 220 having at least three edges 230, 232, 234 and a second major surface 270 defined by a second perimeter 271 having the same number of edges 272, 274, 276 as the first perimeter 220. The second major surface 270 isopposite, and spatially separated from, the first major surface 210 and has the same shape as the first major surface 210. A peripheral surface 280 comprising a plurality of walls 282, 284, 286 is disposed between the first and second major surfaces 210, 270. The peripheral surface 280 has the same number of walls as the first perimeter 220 has edges. The peripheral surface 280 is contiguous with all edges 230, 232, 234, 272, 274, 276 of the first and second perimeters 210, 270.

[0037] Generally, the first and second major surfaces of the shaped particles are substantially parallel, or even parallel; however, this is not a requirement. For example, random deviations due to drying may result in one or both of the first and second major surfaces being non planar. In some embodiments, at least one of the first or second major surfaces is concave. In other embodiments, both the first and second major surfaces are concave.

[0038] In some embodiments, as illustrated in FIG.2, the first and second major surfaces are the same size and the walls of the peripheral surface are orthogonal to the first and second major surfaces, i.e., the dihedral angle A between the wall 286 of the peripheral surface 280 and first perimeter 210 is 90°. In other embodiments, the first and second major surfaces are different sizes and the walls of the peripheral surface are tapered. For example, the walls of the peripheral surface can form a dihedral angle of less than 90 degrees, or less than 85 degrees, or less than 80 degrees, or less than 75 degrees, or less than 70 degrees, or less than 65 degrees, or less than 60 degrees, or less than 55 degrees, or less than 50 degrees with the first or second major surface. In some embodiments, the dihedral angle can independently range from 45 to 90 degrees, or 70 to 90 degrees, or 75 to 85 degrees. In one embodiment, the first major surface is dimensionally larger than the second major surface, and the plurality of walls of the peripheral surface form a dihedral angle of less than 90° with the first major surface.

[0039] In some embodiments, as illustrated in FIG.2, the edges of the first and second perimeters are straight. However, the edges may be straight, inwardly extending (i.e., concave), or a combination thereof. Preferably, the edges are not convex. In some embodiments, at least one edge of the first perimeter is concave. In the same or other embodiments, all edges of the first perimeter are concave.

[0040] FIG 3. illustrates one embodiment of a shaped particle having an inwardly extending edge. The shaped particle 300 comprises first major surface 310 defined by first perimeter 320. First perimeter 320 comprises first, second, and third edges 330, 332, 334. First edge 330 is a concave monotonic curve, while second and third edges 332, 334 are substantially straight edges. First region 390 of first perimeter 320 comprises inwardly extending first edge 330, and terminates at first and second corners 350, 352 defining respective first and second acute interior angles 360, 362. Second major surface 370 is defined by second perimeter 371 having the same number of edges 372, 374, 376 as the first perimeter 320. The second major surface 370 is opposite, and spatially separated from, the first major surface 310. The second major surface 370 has the same shape as the first major surface 310. Therefore, the second perimeter edge 372 opposite the first perimeter edge 330 is also a concave monotonic curve. Peripheral surface 380 comprises a plurality of walls 382, 384, 386 disposed between the first and second major surfaces 310, 370. The peripheral surface 380 is contiguous with all edges of the first and second perimeters 320, 371.

[0041] In other embodiments, more than one edge of the first perimeter may be inwardly extending. For example, referring now to FIG.4A, exemplary shaped particle 500a has first perimeter 520a of first major surface 510a with two inwardly extending regions 590a, 592a formed by edges 530a, 532a and each terminating at two of acute corners 550a, 552a, 554a. Referring now to FIG.5B, exemplary shaped particle 500b has first perimeter 520b of first major surface 510b with three inwardly extending regions 590b, 592b, 594b formed by edges 530b, 532b, 534b and each terminating at two of acute corners 550b, 552b, 554b. Likewise, referring now to FIG.5C, exemplary shaped particle 500c of first major surface 510c has first perimeter 520c with four inwardly extending regions 590c, 592c, 594c, 596c formed by edges 530c, 532c, 534c, 536c at each terminating at two acute corners 550c, 552c, 554c, 556c defining acute interior angles (not shown).

[0042] In some embodiments, interior angles formed between the inwardly extending region and either or both adjacent edges of the perimeter are smaller than would be the case if the inwardly extending region was replaced by a single straight line segment. For example, in the case of an equilateral triangle, all corners have an interior angle of 60 degrees, while for corresponding shapes having a concave edge replacing one of the triangle's edges according to one embodiment of the present disclosure, the interior angles of the two corners adjacent to the inwardly extending region may be substantially reduced. For example, in the case of generally triangular shaped particles the interior angles may be in a range of from 5, 10, 15, 20, 25, or 30 degrees up to 35, 40, 45, 50, or 55 degrees, or from 40 to 55 degrees. In some embodiments, the interior angles may be in a range of from 35 to 55 degrees, from 40 to 55 degrees, or even from 45 to 55 degrees, although other values are also possible. Similarly, if two (or three) of the triangle's edges are replaced with inwardly extending curved edges, the interior angles of their adjacent corners may fall in the same range or be even lower. The same trend occurs in the case of perimeters having four or more edges, although the interior angle values may tend to be larger.

[0043] The interior angle (θ) of a corner of a perimeter is measured by taking the angle formedbetween the tangents (T1, T2) of respective edges forming the corner at their closest point to the cornerthat has not passed an inflection point with respect to the inwardly extending region. In the case ofintersecting straight edges (e.g., as shown in FIG. 5A), tangents T1aand T2ahave the same slope as theedges themselves and the interior angle θ can be easily determined. In the case where one or both of theedges are monotonic inwardly extending curves (e.g., as shown in FIGS. 5B and 5C), the tangents (T1band T2bor T1cand T2c), respectively) can likewise be readily determined by approaching the corneralong the curved edge(s). However, if the corner is round or otherwise deformed (e.g., as shown in FIG. 5D), the measurement of the interior angle of the corner could become more problematic. Accordingly, insuch cases, the tangents T1dand T2dshould be determined by measuring the tangent of each adjacentedge as they approach the inflection points (if present) proximate to the corner, shown as P1and P2inFIG.5D.

[0044] The depth of any inwardly extending edge can be measured as the maximum dimension of the shaped particle parallel to the maximum depth. For example, with reference to FIG.3, the maximumdimension 318 is parallel to maximum depth 315. An inwardly extending region of a shaped abrasive particle according to some embodiments of the present disclosure may have a maximum depth that is at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or even 60 percent of the maximum dimension of the shaped particle parallel to the maximum depth.

[0045] In some embodiments, at least one edge of the first perimeter extends inwardly as a concave monotonic curve and terminates at two corners defining first and second acute interior angles, wherein the first acute interior angle is in the range of from 35 to 55 degrees, wherein the second acute interior angle is in the range of from 35 to 55 degrees, wherein the inwardly extending edge has a maximum depth that is at least 5 (or 10, 25, 30, 35, 40, 45, 50, 55 or 60) percent of the maximum dimension of the shaped particle parallel to the maximum depth. In the same or different embodiments, all edges of the first perimeter extend inwardly as a concave monotonic curve and each terminates at two sharp corners defining first and second acute interior angles, wherein the first acute interior angle is in the range of from 35 to 55 degrees, wherein the second acute interior angle is in the range of from 35 to 55 degrees, wherein each of the inwardly extending edges has a maximum depth that is at least 5 (or 10, 25, 30, 35, 40, 45, 50, 55 or 60) percent of the maximum dimension of the shaped particle parallel to the maximum depth.

[0046] The particles of the present disclosure are typically thin platelets having a shape based upon the geometric configuration of the first and second perimeters of the first and second major surfaces, respectively. Since the first and second major surfaces are the same shape, though not necessarily the same size, shape can be described with respect to the first major surface, with the understanding that such description applies to the second major surface, as well.

[0047] The first perimeter is made up of well-defined edges that can take on a variety of geometric shapes. The first perimeter is typically made up of at least three edges. However, the first perimeter can have 3, 4, 5 or even 6 edges. In some embodiments, the first perimeter can have 3 to 6 edges. In some preferred embodiments, the first perimeter has 3 edges. In another preferred embodiment, the first perimeter has 4 edges. The geometric shape of the first perimeter can include triangles, squares, rectangles, pentagons, hexagons, diamonds, stars and truncated versions thereof (e.g., square pyramidal).

[0048] In preferred embodiments, the edges making up the first and second perimeters of the shaped particle exhibit a radius of curvature of less than 50 micrometers, or less than 45 micrometers, or less than 40 micrometers, or less than 35 micrometers, or less than 30 micrometers, or less than 25 micrometers, or less than 20 micrometers. FIGS.6A and 6B illustrates the radius of curvature at the edge 673 of a truncated pyramid. In general, the smaller the radius of curvature, the sharper the edges of the shaped particle. Sharper edges can provide greater resistance to tight packing, helping to reduce back pressure in a packed column used in chromatographic techniques.

[0049] In some embodiments, the length of the shaped particles is at least 200 micrometers, or at least 500 micrometers, or at least 575 micrometers, or at least 1 millimeter, or at least 2 millimeters, or at least 3 millimeters, or at least 4 millimeters. In the same or additional embodiments, the length of the shaped particles is no greater than 5 millimeters, or no greater than 4 millimeters, or no greater than 3millimeters, or no greater than 1 millimeter. In some embodiments, the length of the shaped particle is 200 micrometers to 5 millimeters, more particularly 1 millimeter to 5 millimeters, or even more particularly 2 millimeters to 4 millimeters. The term “length” as used herein refers to the dimension of the maximum extent across the first and second major surfaces of the shaped particle. For example, in the case of a shaped particle having equilateral triangles as the first and second major surfaces, the length would be determined by the size of an edge of the largest equilateral triangle making up the shaped particle. In the case of shaped particles having squares as the first and second major surfaces, the length would be determined by the size of the diagonal of the largest square making up the shaped particle. Length is based upon the dimensions of a planar surface. Therefore, if the first and / or second major surface exhibit concavity, the length is determine by the plane encompassed by the respective first and / or second perimeter.

[0050] Typically, the shaped particles disclosed herein have a thickness that is substantially less than their length and / or width. The term “width” as used herein refers to a direction that is orthogonal to, and in the same plane as, the length. The term “thickness” as used herein, refers to the dimension of the maximum extent that extends between the first and second major surfaces of the particle and is orthogonal to both the length and width of the particle. The length of the shape particles disclosed herein are typically at least 2, at least 3, or at least 4, or at least 5, or at least 6, or at least 7 times greater than the thickness of the particle.

[0051] In preferred embodiments, the plurality of shaped particles disposed within the reservoir are substantially uniform in size. The term “substantially” as used in this context means that at the 95% confidence interval, the shaped particles have a characteristic dimension (i.e., same geometric dimension on each particle) within 35%, 30%, 25%, 20%, 15%, 10%, or even 5% of the mean. Particles of substantially uniform size pack less efficiently than particles of varying size, where smaller particles can fill the voids created between larger particles. Thus, having particles of substantially uniform size can help reduce back pressure in packed beds or columns when contrasted with particles have a multimodal size distribution.

[0052] The shaped particles disclosed herein are typically porous. In some embodiments, the shaped particles have a porosity of 10 m2 / g or greater, 25 m2 / g or greater, 50 m2 / g or greater, 100 m2 / g or greater, 200 m2 / g or greater, or even 500 m2 / g or greater. Porosity can be determined using the nitrogen adsorption method and application of BET theory. This method is commonly used to determine surface area and involves adsorbing a monolayer of nitrogen on the surface of the precision-shaped particle under cryogenic conditions. The amount of adsorbed nitrogen is proportional to the surface area. If desired, information related to pore size can be obtained by allowing continued adsorption of nitrogen under cryogenic conditions, until the entire pore structure is filled with liquid nitrogen, and applying BJH theory (or other theory) to calculate average pore diameter. This method generally measures pores having an average diameter up to about 2000 Angstroms. For materials having larger pore sizes, mercury intrusion porosimetry may be utilized to measure average pore diameters.

[0053] Generally, the shaped particles disclosed herein have a Moh’s hardness of less than 8, making them less suited to abrasive applications. Composition

[0054] The shaped lithium adsorbent particles comprise a lithium adsorbent material. The term “lithium adsorbent material” as used herein refers to a two- or three-dimensional network of ions and / or atoms that can reversibly take up lithium ions from solutions (e.g., salt brines).

[0055] Exemplary lithium adsorbent materials include those having the formula LiX^nM(OH)3^mH2O, where X is at least one anionic species (e.g., Cl-, OH-), M is at least one of a trivalent metal ion selected from the group consisting of Al, Ga, In and, optionally, at least one transition metal ion, and n is selected so that the mole ratio of M to Li is at least 1:1, or at least 1.5:1, or at least 2:1. In some embodiments, the transition metal ion is selected from the group consisting of Fe, Ti, Mn, Cr, Co, Ni, Cu, Zn, Zr, Nb, Mo, W, Ag, or combinations thereof. Lithium adsorbent materials in this category include Li-Al layered double hydroxide (LDH).

[0056] Other exemplary lithium adsorbent materials include those having the formula LixMyOz, where M is a metal ion selected from the group consisting of Ti, Mn, Cr, Co, Ni, Cu, Zn, Zr, Nb, Mo, W, Ag, Sn, Ge, Si, Al, or combinations thereof, and x, y and z are selected to conserve electrical neutrality. Such material include Li4Mn5O12, LiMnO2, Li2MnO2, LiMn2O4, Li2Mn2O4, Li1.6Mn1.6O4,or Li2MnO3, Li2SnO3, LiCuO2, Li4Ti5O12, Li2TiO3, Li4Ti5O12, Li4TiO4, and Li7Ti11O24.

[0057] Additional exemplary lithium adsorbent materials include Li4Mn5O12, LiMnO2, Li2MnO2, LiMn2O4, Li2Mn2O4, Li1.6Mn1.6O4,or Li2MnO3, Li2SnO3, LiCuO2, Li3VO4, Li2Si3O7, LiFePO4,LiMnPO4, Li2CuP2O7, Al(OH)3, H2TiO3, Li4Ti5O12, Li2TiO3, Li4Ti5O12, Li4TiO4, Li7Ti11O24, or combinations thereof. Method of Making Shaped Particles

[0058] One exemplary method for making the shaped particles comprises adding a lithium adsorbent dispersion to a mold having one or more shaped cavities, drying the lithium adsorbent dispersion to form shaped lithium adsorbent particles, and removing the shaped lithium adsorbent particles from the mold. The dispersions can be made from commercially available lithium adsorbent material. Alternatively, if not readily available, the lithium adsorbent material can be made from other sources. For example, Li-Al layered double hydroxide (LDH) is not readily available but may be made by converting powders of LDH precursors to LDH. LDH precursor particles include, for example, Al(OH)3(gibbsite or bayerite), AlO(OH) (boehmite), AlOOH^xH2O (pseudoboehmite), diaspore, bauxite, activated alumina, amorphous alumina, or combinations thereof. The powders are added to a basic solution comprising lithium ions, typically with heating in the range of 50-95˚C, and the solution is subsequently neutralized with an acid to form the shaped LDH particles. In some embodiments, the basic solution comprises LiOH. In other embodiments, the basic solution comprises a lithium salt (e.g., LiCl) and an alkali metal base (e.g., NaOH, KOH, or LiOH). The LDH particles can be separated from the neutralized solution using standard separation techniques (e.g., gravity filtration). More details steps are outlined below.

[0059] The lithium adsorbent dispersion typically comprises particles of the lithium adsorbent material and a volatile liquid. In one embodiment, the volatile liquid component is water. The lithium adsorbent dispersion should comprise a sufficient amount of liquid for the viscosity of the dispersion to be sufficiently low to enable completely filling the mold cavities and replicating the mold surfaces, but not so much liquid as to cause subsequent removal of the liquid from the mold cavity to be prohibitively expensive.

[0060] A peptizing agent can be added to the dispersion to produce a more stable hydrosol or colloidal lithium adsorbent dispersion. Suitable peptizing agents are monoprotic acids or acid compounds such as acetic acid, hydrochloric acid, formic acid, and nitric acid. Multiprotic acids can also be used but they can rapidly gel the dispersion, making it difficult to handle or to introduce additional components thereto.

[0061] The dispersion (e.g., sols or slurries) can be formed by any means. For example, the lithium adsorbent material particles can be dispersed in a volatile liquid containing peptizing agent using high shear mixer. Alternatively, the peptizing agent can be added after mixing the lithium adsorbent material particles in the volatile liquid. In some embodiments, the dispersion comprises from 20 to 90 percent by weight, or 20 to 70 percent by weight, or 30 to 60 percent by weight of the lithium adsorbent material particles. In some embodiments, the dispersion comprises 10 to 80 percent by weight, or 30 to 80 percent by weight, or 40 to 70 percent by weight of the volatile component.

[0062] Defoamers or other suitable chemicals can be added to reduce the tendency to form bubbles or entrain air while mixing. Additional chemicals such as wetting agents, alcohols, or coupling agents can be added if desired.

[0063] The dispersion is shaped by providing a mold having at least one mold cavity, and preferably a plurality of cavities formed in at least one major surface of the mold.

[0064] The shaped particles of the present disclosure can typically be made using tools (or molds that are inverse replicas thereof) cut using diamond tooling, which provides higher feature definition than other fabrication alternatives such as, for example, stamping or punching. Typically, the cavities in the tool surface have smooth faces that meet along sharp edges. This higher feature definition allows for the formation of shaped particles having edges with a smaller radius of curvature, as mentioned above. The resultant shaped particles have a respective nominal average shape that corresponds to the shape of cavities in the tool surface; however, variations (e.g., random variations) from the nominal average shape may occur during manufacture, and shaped particles exhibiting such variations are included within the definition of shaped particles as used herein.

[0065] Referring now to FIG.7, exemplary mold 700 defines mold cavity 795. Mold cavity 795 is laterally bounded by peripheral mold surface 780 comprising first, second, and third mold walls 782, 784, 786. Mold cavity 795 has outer opening 797 defined by a perimeter 720. First mold wall 782 intersects perimeter 720 at first edge 730. Second mold wall 784 intersects perimeter 720 at second edge 732. First region 790 of perimeter 720 extends inwardly and comprises first edge 730, which terminates at first and second corners 750, 752, which define respective first and second acute interior angles 760, 762.

[0066] In some embodiments, the mold is formed as a production tool, which can be, for example, a belt, a sheet, a continuous web, a coating roll such as a rotogravure roll, a sleeve mounted on a coating roll, or a die. In one embodiment, the production tool comprises polymeric material. Examples of suitable polymeric materials include thermoplastics such as polyesters, polycarbonates, poly(ether sulfone), poly(methyl methacrylate), polyurethanes, polyvinylchloride, polyolefin, polystyrene, polypropylene, polyethylene or combinations thereof, or thermosetting materials. In one embodiment, the entire tooling is made from a polymeric or thermoplastic material. In another embodiment, the surfaces of the tooling in contact with the dispersion while drying, such as the surfaces of the plurality of cavities, comprises polymeric or thermoplastic materials and other portions of the tooling can be made from other materials. A suitable polymeric coating may be applied to a metal tooling to change its surface tension properties by way of example.

[0067] A polymeric or thermoplastic production tool can be replicated off a metal master tool. The master tool will have the inverse pattern desired for the production tool. The master tool can be made in the same manner as the production tool. In one embodiment, the master tool is made out of metal, e.g., nickel and is diamond turned. In one embodiment, the master tool is at least partially formed using stereolithography. The polymeric sheet material can be heated along with the master tool such that the polymeric material is embossed with the master tool pattern by pressing the two together. A polymeric or thermoplastic material can also be extruded or cast onto the master tool and then pressed. The thermoplastic material is cooled to solidify and produce the production tool. If a thermoplastic production tool is utilized, then care should be taken not to generate excessive heat that may distort the thermoplastic production tool limiting its life. More information concerning the design and fabrication of production tooling or master tools can be found in U.S. Pat. No.5,152,917 (Pieper et al.); U.S. Pat. No.5,435,816 (Spurgeon et al.); U.S. Pat. No.5,672,097 (Hoopman et al.); U.S. Pat. No.5,946,991 (Hoopman et al.); U.S. Pat. No.5,975,987 (Hoopman et al.); and U.S. Pat. No.6,129,540 (Hoopman et al.).

[0068] Access to cavities can be from an opening in the top surface or bottom surface of the mold. In some instances, the cavities can extend for the entire thickness of the mold. Alternatively, the cavities can extend only for a portion of the thickness of the mold. In one embodiment, the top surface is substantially parallel to bottom surface of the mold with the cavities having a substantially uniform depth. At least one edge of the mold, that is, the edge in which the cavities are formed, can remain exposed to the surrounding atmosphere during the step in which the volatile component is removed.

[0069] The cavities have a specified three-dimensional shape to make the shaped particles. The depth dimension is equal to the perpendicular distance from the top surface to the lowermost point on the bottom surface. The cavities of a given mold can be of the same shape or of different shapes.

[0070] The cavities in the mold are filled with the dispersion using conventional techniques. In some embodiments, a knife roll coater or vacuum slot die coater can be used. A mold release can be used to aid in removing the particles from the mold if desired. Typical mold release agents include oils such as peanut oil or mineral oil, fish oil, silicones, polytetrafluoroethylene, zinc stearate, and graphite. In general, mold release agent such as peanut oil, in a liquid, such as water or alcohol, is applied to thesurfaces of the production tooling in contact with the alumina precursor dispersion such that between about 0.1 mg / in2(0.02 mg / cm2) to about 3.0 mg / in2(0.5 mg / cm2), or between about 0.1 mg / in2(0.02 mg / cm2) to about 5.0 mg / in2(0.8 mg / cm2) of the mold release agent is present per unit area of the mold when a mold release is desired. In some embodiments, the top surface of the mold is coated with the dispersion. The dispersion can be pumped onto the top surface.

[0071] Next, a scraper or leveler bar (i.e., a screed) can be used to force the dispersion fully into the cavity of the mold. The remaining portion of the dispersion that does not enter the cavity can be removed from the top surface of the mold and recycled. In some embodiments, a small portion of the dispersion can remain on the top surface and in other embodiments the top surface is substantially free of the dispersion. The pressure applied by the scraper or leveler bar is typically less than 100 psi (0.7 MPa), less than 50 psi (0.3 MPa), or even less than 10 psi (69 kPa). In some embodiments, no exposed surface of the dispersion extends substantially beyond the top surface.

[0072] In those embodiments wherein it is desired to have the exposed surfaces of the cavities result in substantially planar faces of the shaped particles, it may be desirable to overfill the cavities (e.g., using a micronozzle array) and slowly dry the dispersion.

[0073] The dispersion is then dried to remove the volatile component and form shaped particles. Desirably, the volatile component is removed by fast evaporation rates. In some embodiments, the volatile component is evaporated away at room temperature over a period of time. In other embodiments, the dispersion is dried at elevated temperatures below the boiling point of the volatile solvent (e.g., approximately 60°C for water) in order to speed up drying. In some other embodiments, removal of the volatile component by evaporation occurs at temperatures above the boiling point of the volatile component. An upper limit to the drying temperature often depends on the material the mold is made from. For polypropylene tooling the temperature should be less than the melting point of the plastic. In one embodiment, for a water dispersion of between about 40 to 50 percent solids and a polypropylene mold, the drying temperatures can be between about 90° C to about 165° C, or between about 105° C to about 150° C, or between about 105° C to about 120° C. Higher temperatures can lead to improved production speeds but can also lead to degradation of the polypropylene tooling limiting its useful life as a mold.

[0074] The shaped particles can be removed from the mold cavities using one or more convention techniques (e.g., gravity, vibration, ultrasonic vibration, vacuum, or pressurized air). Applications

[0075] The shaped particles of the present disclosure can be used to separate lithium ions from fluids using a device similar to that illustrated in FIG.1. The device 6 comprises a reservoir 8 having a fluid inlet 12 and a fluid outlet 14. A plurality of shaped particles 16 is disposed within the reservoir 8 (e.g., a packed bed of shaped particles). The design of the reservoir is not particularly limiting as long as it retains the shaped particles while allowing fluid to flow through the shaped particles in the reservoir. In some embodiments, as illustrated in FIG.1, the reservoir is a column that allows for the downwardgravitational flow of fluid in the column. Optional pumps (not shown) may be added to further assist gravitational flow of fluid through the column. Suitable columns may be constructed from a variety of materials, including glass, polymeric material, stainless steel, titanium and alloys thereof, or nickel and alloys thereof. In an alternative embodiments, the reservoir could be a large tank where fluid flows over the solid particles in a more horizontal direction. The tank could be tilted to allow for gravitational flow and / or utilize pumps to keep the fluid moving through the tank. In one embodiment, the method comprises disposing the shaped particles in a reservoir having a fluid inlet and a fluid outlet, contacting a solution comprising lithium ion with the shaped particles in the reservoir, and separating at least a portion of the lithium ion from the solution. The extracted lithium ion can then be converted by other processes to lithium salts (e.g., lithium carbonate or lithium hydroxide) for use in a variety of products, including laptops, cell phones, electric vehicles, and energy storage systems.

[0076] The shaped particles of the present disclosure are designed to allow for high volumetric surface area while also reducing packing density. The former enhances interaction with the chemical species to be separated. The latter reduces the potential back pressure in the device which can add to cost and inefficiencies in the process. In some embodiments, the reservoir is a vertical column and the shaped particles within the column have a void volume of a least 35 percent, or at least 40 percent, or at least 45 percent, or at least 50 percent. In other embodiments, the reservoir is a vertical column and the shaped particles within the column have a void volume of no greater than 80 percent, or no greater than 75 percent, or no greater than 70 percent, or no greater than 60 percent. In some embodiments, the reservoir is a vertical column and the shaped particles within the column have a void volume of 35-80 percent, or 40-75 percent, or 40-60 percent.

[0077] In some embodiments, the permeability of a fluid through the plurality of shaped particles as disclosed herein is at least 1.5 times greater, at least 2 time greater, or at least 3 times greater than the permeability of the same fluid through a batch of spherical particles, each spherical particle having the same composition and volumetric surface area as the shaped particles. Examples

[0078] Objects and advantages of this invention are further illustrated by the following examples, but the particular materials and amounts thereof recited in these examples, as well as other conditions and details, should not be construed to unduly limit this invention. These examples are merely for illustrative purposes only and are not meant to be limiting on the scope of the appended claims.

[0079] The following abbreviations are used in the Example Section: g = gram, mg = milligram, lb = pound, L = liter, mL = milliliter, gal = gallon, m = meter, cm = centimeter, mm = millimeter, µm = micrometer, nm = nanometer, in = inch, ˚C = degrees Celsius, h = hour, min = minute, % = percent, wt% = weight percent, ppm = parts per million.

[0080] Table 1. Abbreviations and Materials Used in the Examples Name Description Source and Trade Name SAP1 Shaped alumina particles 1 Made in accordance with paragraph

[0128] in U.S. Pat. No.8764865 SAP2 Shaped alumina particles 2 Made in accordance with column 22, line 32 in U.S. Pat. No.9771504 GAP Granular alumina particles Obtained under the trade designation CUBITRON 321 from 3M Company in St. Paul, Minnesota USA YTZ Yttria-stabilized zirconia Tosoh America in Grove City, Ohio USA milling media ATH Aluminum trihydrate See below Dadco SH 20 Aluminum trihydrate Dadco Alumina and Chemicals Limited in Niedereschach, Germany Micral 932 Aluminum trihydrate Huber Corp. in Edison New Jersey USA DISPERAL P2 Boehmite Sasol North America, Inc. in Houston, Texas USA LiOH Lithium hydroxide Thermo Scientific in Fair Lawn, New Jersey USA NaOH Sodium hydroxide Thermo Scientific AA Glacial acetic acid EMD in Gibbstown, New Jersey USA HCl Hydrochloric acid EMD HNO3Nitric acid (67-70%) VWR BDH Chemicals in Solan, Ohio USA LiCl Lithium chloride Thermo Scientific NaCl Sodium chloride VWR BDH Chemicals CaCl2Calcium chloride dihydrate Mallinckrodt in Phillipsburg,New Jersey USA KCl Potassium chloride EMD B(OH)3Boric acid VWR BDH Chemicals Methylene blue dye Alfa Aesar in Heysham, England CP5 Alumina powder BASF Li2CO3Lithium carbonate Alfa Aesar in Ward Hill, Massachusetts USA TiO2Titanium oxide Obtained under the trade designation AEROXIDE P25 from Nippon Aerosil Co., Ltd. in Tokyo, Japan SOKALAN CP Dispersant Obtained under the trade designation SOKALAN N40v CP N40v from BASF in Charlotte, North Carolina USA Methods Particle Size

[0081] Particle size was measured using Horiba 610 analyzer. Bulk Density

[0082] The bulk density was measured by pouring a mass of particles into a graduated cylinder and measuring the volume occupied by those particles. The bulk density equals the mass divided by the volume of those particles and is expressed in g / mL. Tapped Density

[0083] Tap density was measured with a Micromeritics Geopyc 1360 at a force of 10N and is expressed in g / mL.Pycnometer Density

[0084] True density was measured by Micromeritics Helium Pycnometer Accupyc II TEC and is expressed in g / mL. Volumetric Surface Area

[0085] Surface area to volume ratio for spheres and SAP1 were calculated geometrically using measurements of the diameter, edge length, and aspect ratio of the particles. For SAP2 the CAD model of the particles allowed derivation of a factor relating the distance between the corners, a, of the SAP2 particle and the surface area to volume ratio. For this shape, (SA x a) / V = 21.73413. Using this factor and a, the SA / V for particles of different sizes were calculated. For the GAP particle, ellipsoid geometry was assumed for calculation of the surface area and volume. The maximum and minimum diameter of the particles were quantified with the auto area function of a Keyence VHX 5000 microscope. The third dimension of the particle was assumed to be equivalent to the minimum dimension. The Angle of Repose

[0086] The angle of repose was measured by placing a funnel at a consistent height above a surface and pouring particles through the funnel so that a pile was formed. The width and height of the pile were measured, and the angle of repose was calculated as the arctan of the height of the pile divided by the radius of the pile. A higher angle of repose indicates lower particle flowability and poorer particle packing. Carr’s Index and Hausner Ratio

[0087] The bulk density and tap density were measured as described above.

[0088] The Carr’s Index and Hausner Ratio were calculated from the measured densities. Carr’s Index is calculated as the percentage of the tapped density minus the bulk density divided by the tapped density. Hausner ratio is equivalent to the tapped density divided by the bulk density. Carr’s Index is low for particles with good flow and high for particles with poor flow. Carr’s Index <10 is considered excellent, as for spheres. Carr’s Index >38 is considered approximately no flow. Hausner ratio is equivalent to the tapped density divided by the bulk density thus for excellent flow Hausner ratio=1. Hausner’s ratio >1.6 is considered approximately no flow. Void Percent (%) of Packed Particles

[0089] Bulk density was performed by pouring particles into a 10 mL graduated cylinder and measuring the volume and mass of particles.

[0090] True density was measured by Micromeritics Helium Pycnometer Accupyc II TEC.

[0091] Void % was calculated as 1-(bulk density / true density) *100. Permeability Testing

[0092] Permeability measurement of packed beds of shaped and unshaped particles was performed by loading an Ace Glass chromatography column of diameter 0.8 cm and height 25 cm with a slurry of7.5 mL of particles in 10 mL of water to give a stationary phase particle bed. The column was tapped during the packing process. Several bed volumes of deionized water were flowed through the bed after packing. The bed height was measured. An aqueous solution of methylene blue dye mobile phase was loaded onto the column. The column exit was opened and the time for the dye solution to traverse the column stationary phase was recorded. The time, bed length, density and viscosity of the mobile phase, and acceleration due to gravity were used to calculate the permeability for the column of each stationary phase of particles. Measurement of Cation Concentration

[0093] For all samples, approximately 100 mg were weighed to the nearest 0.01 mg directly into 50 mL polypropylene centrifuge tubes. For desorption experiments, samples were diluted to 25 mL using 2% nitric acid (HNO3). For adsorption experiments, samples were originally diluted to 25 mL and were diluted an additional 100-fold by volume using 2% nitric acid (HNO3), prior to analysis, to bring analytes (Ca, K, Na) within linear calibration range.

[0094] The instrument used for elemental analysis was a PerkinElmer Optima 8300 ICP optical emission spectrophotometer. The samples were analyzed against external calibration curves generated using acid-matched solution standards containing 0, 0.2, 0.5, and 1 ppm of each analyte. A 0.5 ppm quality-control standard was used to monitor the accuracy of the calibration curves throughout the analysis. Additionally, a 0.5 ppm scandium solution was run in-line with the samples and standards to serve as an internal standard. The elements determined and quantified in this analysis were B, Ca, K, Li, Na. Powder X-ray Diffraction

[0095] X-ray diffraction patterns were collected with a Rigaku Miniflex 600 diffractometer. Examples Examples (EX) 1-4 (Triangular)

[0096] Shaped alumina particles with triangular cross-section (SAP1) produced according to the disclosure of paragraph

[0128] of U.S. Pat. No.8764865 (Boden et al.) from 3M Company in Saint Paul, Minnesota USA. SAP1-1 to SAP1-3 have edge-length / thickness of 4:1. SAP1-4 has edge- length / thickness of 3:1. Optical images of the SAP1 particles were taken with a Keyence VHX 5000 microscope are provided in FIGS.8A-8B. Measurements are provided in Table 2 below. Examples (EX) 5-8 (Curved-Edge Triangular)

[0097] Shaped alumina particles with curved-edge triangular cross-section (SAP2) produced according to the disclosure of column 22, line 32 of U.S. Pat. No.9771504 (Adefris) from 3M Company in Saint Paul, Minnesota USA. SAP2-1 to SAP2-3 have point-to-point-length / thickness of 4:1. SAP2-4 has point-to-point-length / thickness of 3:1. Optical images of the SAP2 particles were taken with aKeyence VHX 5000 microscope are provided in FIGS.9A-9B. Measurements are provided in Table 2 below. Comparative Examples (CE) 1-5

[0098] Commercial spherical yttria-stabilized zirconia milling media from Tosoh with tight diameter distributions. Measurements are provided in Table 2 below. Comparative Example (CE) 6

[0099] Granular abrasive particles attained from 3M Company in Saint Paul, Minnesota USA with broad diameter distribution. Measurements are provided in Table 2 below.% di 1.3 7.4.8.0.2.9.2. - - -3.o 545266506566V6369- - - -8.305r)eL tem / mg5o (541802nyt3659. 88.8. 97916128. 88479. 88. 98. 0259.- - -630.- - - -09.cyisn3 3 3 3 3 3 3 3 6 3Pedrensoit 12. 32. 72. 03. 51. 03. 33. 22.- - -50.- - - -7ua ar1 1 1 1 1H1 1 1 1 1.1s’rrxaed7n.7 4.5 2 1 0 6 818.1.3.3.3.4.7- - - 4.4 - - - -6.41 2 2 1 2 2 1 1 IC )dy 2 8 9 5 6 4 2 4 6t3eLi 2 4 0 0 4 1 9 1 75ps 4 5 5 9 3 5 0 5- - - - - - -4m8pn / 2 1 8 1 8 7 7 7.2a. . . . . . . . .e g32 2 1 2 1 1 1 1 2 ( dT )ytiLk5 6 5 8 9 5 9 4 8 2ls 8 7 4 6 5 3 2 4 6 9 - - - - - - -umn . . . . . . . . . . / e 1 1 1 1 1 1 1 1 3 1Bg(D )fseoes 8 6 8 6 5 2 8 9e e. . . . . . . .ol r - - - - - - -3 8 8 0 1 0 2 7pg ge 2 2 2 3 3 3 3 1enr dA(e )mL94 4u 70 3 8 2 0 0 5 2 6 6 8 8 1m6 6 7l 1 2 2 4 1 3 4 6 1 / 5 2 2 1 1o0 0 02 0 0 0 0 0 0 0 0 00 0 0 0 0.0 0 0. . . . . . . . . . . . .V . . .m / 00 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0uA(S6-1ytiE0 1 1 1 0 1 1 1 2 1 1 1 1 0 0 0 0li 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 C)- - - - - - - - - - - - - - - - -b 2aE E E E E E E E E E E E E E E E Edme2 7 4 3 8 2 7 6 4 8 9 2 6 0 6 1 3n(6 9 9 7 1 5 6 2 0 3 5 7 1 2 1 5 2am. . . . . . . . . . . . . . . . .r1 5 3 1 2 6 4 2 3 1 1 3 3 1 2 2 18e-P1X)niEem2 9 8l. 9 3 7 . 5 4 3 5 0 0 1 1 5 3 3 .mc. . . . . . . . . . . . . .µ xm 3 8 2i( a7 0 3 8 3 6 4 3 3 9 9 4 2 2t 58 4 5or .6 4 2 2 4 3 1 3 3 3 3 6 4 4erm4 2 0a 96 5 3 7 5 3 1 2 2 3 3 5 9 9zf 1 1i 1P7 sa 6taD21 3 4 1 2 3 4- - - - - - --. PZ Z Z Z Z Z Z Z11 1 1 2 2 2 22T T T T T T T T APPP P P P P PeY Y Y Y Y Y Y YlGA A AA A A A AS SSSS S S SbaT elp 1 2 2 3 3 4 5 5 6m E E E E E E E E E1 2 3 4 5 6 7 8a]C C C C C C C C Cx0E010[Example 9

[0101] 100 g of activated aluminum oxide obtained from BASF under trade designation CP5 was dispersed by high shear mixing in a solution containing 100 g of water and 30 g of glacial acetic acid for 5 minutes. The resulting slurry was aged for at least 1 hour before coating. The slurry was coated onto a production tooling having shaped mold cavities according to the disclosure of paragraph

[0128] of U.S. Pat. Appln. Publ. No.2010 / 0146867 (Boden et al.).

[0102] A mold release agent, 1 percent peanut oil in methanol, was used with about 0.5 mg / in2(0.08 mg / cm2) of peanut oil applied to the production tooling having an array of mold cavities. The excess methanol was removed by drying at room temperature. The slurry was forced into the cavities with a putty knife so that the openings of the production tooling were completely filled. The coated production tooling was left at room temperature in air to dry. The shaped particles were removed from the production tooling by passing it over an ultrasonic horn. Example 10

[0103] 160 g of pseudoboehmite powder obtained from Sasol North America under trade designation Disperal was dispersed by high shear mixing in a solution containing 230 g of water and 5 g of 70% nitric acid for 5 minutes. The resulting slurry was aged for at least 1 hour before coating. The slurry was coated onto a production tooling having shaped mold cavities according to the disclosure of paragraph

[0128] of U.S. Pat. Appln. Publ. No.2010 / 0146867 (Boden et al.).

[0104] A mold release agent, 1 percent peanut oil in methanol, was used with about 0.5 mg / in2(0.08 mg / cm2) of peanut oil applied to the production tooling having an array of mold cavities. The excess methanol was removed by drying at room temperature. The sol-gel was forced into the cavities with a putty knife so that the openings of the production tooling were completely filled. The coated production tooling was left at room temperature in air to dry. The shaped particles were removed from the production tooling by passing it over an ultrasonic horn.

[0105] Some particles were further calcined at temperatures ranging from 300˚C to 700˚C to generate dehydrated alumina. Either the uncalcined or calcined particles can be converted to LDH. Example 11

[0106] A sample of aluminum trihydrate slurry was made by dispersing 160 g of aluminum trihydrate powder, obtained from Huber North America under trade designation Micral 932, 40 g of boehmite powder obtained from Sasol North America designated as DISPERAL P2, 250 g of water and 10 g of aqueous acetic acid. The slurry was shear mixed for 10 minutes. The mixture was aged for at least one hour before coating. The gelatinous slurry was forced into production tooling having shaped mold cavities.

[0107] A mold release agent, 1 percent peanut oil in methanol, was used with about 0.5 mg / in2(0.08 mg / cm2) of peanut oil applied to the production tooling having an array of mold cavities. The excessmethanol was removed by drying at room temperature. The sol-gel was forced into the cavities with a putty knife so that the openings of the production tooling were completely filled. The coated production tooling was left at room temperature in air to dry. The shaped particles were removed from the production tooling by passing it over an ultrasonic horn. Example 12

[0108] 7000 g of DI water was placed in a mixing tank of high energy bead mill MMP1 obtained from Buhler Corp. and containing 200 micron milling media obtained from Tosoh under trade designation YTZ. 30 g of 67% HNO3was subsequently added to the water and the mill was started.2800 g of aluminium hydroxide, Al(OH)3obtained from Huber Corp. under trade designation Micral 932 was added to the mixing tank in about 15 min. At the end of 120 min of milling the particulate colloidal solution was discharged. Significant translucent character of this sol was noted, indicating very fine particulate size. The sol exhibited a strong tendency to gel, a behavior very similar to dispersed boehmite sols in acidic conditions. Particle size was measured using Horiba 610 analyzer with D50 of 0.09 micron and D90 of 0.23 micron.

[0109] About 3000 g of the sol was dried in glass trays and crushed into granules.

[0110] Granules were sieved to the particle sizes between 1 mm and 300 micron in size. Example 13

[0111] Prepared as in Example 12 above.

[0112] 7000 g of DI water was placed in a mixing tank of high energy bead mill MMP1 obtained from Buhler Corp. and containing 200 micron milling media obtained from Tosoh under trade designation YTZ. 30 g of 67% HNO3was subsequently added to the water and the mill was started.2800 g of aluminium hydroxide, Al(OH)3obtained from Huber Corp. under trade designation Micral 932 was added to the mixing tank in about 15 min. At the end of 120 min of milling the particulate colloidal solution was discharged. Significant translucent character of this sol was noted, indicating very fine particulate size. The sol exhibited a strong tendency to gel, a behavior very similar to dispersed boehmite sols in acidic conditions. Particle size was measured using Horiba 610 analyzer with D50 of 0.09 micron and D90 of 0.23 micron. The gelatinous slurry was forced into production tooling having shaped mold cavities.

[0113] A mold release agent, 1 percent peanut oil in methanol, was used with about 0.5 mg / in2(0.08 mg / cm2) of peanut oil applied to the production tooling having an array of mold cavities. The excess methanol was removed by drying at room temperature. The sol-gel was forced into the cavities with a putty knife so that the openings of the production tooling were completely filled. The coated production tooling was left at room temperature in air to dry. The shaped particles were removed from the production tooling by passing it over an ultrasonic horn.Example 14

[0114] Prepared as in Example 13 above with the exception that 1 wt.% of iron oxide and 1.5 wt.% of magnesium oxide was additionally added to the mixture.

[0115] The particles were calcined at 290˚C. XRD analysis confirmed partial conversion to gamma alumina phase; both ATH gibbsite and LDH were present. The particles can be converted to LDH. Example 15

[0116] A 234 g portion of ATH granules from Example 12 was reacted with 692 g of a solution containing 9.2 wt % LiCl and 8.7 wt % NaOH in a closed 1 liter plastic bucket placed in an oven at 70˚C for 12 h. XRD analysis confirmed conversion of ATH gibbsite to LDH phase. Example 16

[0117] A 50 g portion of ATH shaped particles from Example 13 was reacted with 200 g of a solution containing 25 g of LiOH in a closed 0.5 L plastic bucket placed in an oven at 70˚C for 12 h. XRD analysis confirmed conversion of ATH gibbsite to LDH phase. Example 17

[0118] Aluminum trihydrate (50 g) available as Dadco SH-20 from Dadco Alumina and Chemicals Limited was added to water (112.5 g) and mixed with an overhead stirrer. LiOH (6.5 g) was dissolved in water (112.5 g) and then added to the ATH slurry. Mixing proceeded at 95˚C for 17 h. The slurry was neutralized with hydrochloric acid until the pH was ~ 5. XRD analysis confirmed conversion of ATH gibbsite to LDH phase. Example 18

[0119] Aluminum trihydrate (40.7 lb) available as Dadco SH-20 from Dadco Alumina and Chemicals Limited was added to water (78 lb) and mixed with a Hockmeyer mixer in a 55 gal drum. LiOH (11.0 lb) was dissolved in water (77 lb) and then added to the ATH slurry. Mixing proceeded at 60˚C for 16 h. The resulting material was a soft solid of particle size 4.5 um. XRD analysis confirmed conversion of ATH gibbsite to LDH phase. Example 19

[0120] Boehmite powder available as DISPERAL P2 (25 g) from Sasol North America, Inc. was dispersed by high shear mixing in a solution containing 200 g water and 9.1 g of 67% nitric acid for 5 minutes. LDH (135 g) available from Example 18 above was added and mixed for 10 minutes. Per below the LDH may be LDH-OH or LDH-Cl. The mixture was aged for at least one hour before coating. The gelatinous slurry was forced into production tooling having shaped mold cavities.

[0121] A mold release agent, 1 percent peanut oil in methanol, was used with about 0.5 mg / in2(0.08 mg / cm2) of peanut oil applied to the production tooling having an array of mold cavities. The excess methanol was removed by drying at room temperature. The sol-gel was forced into the cavities with aputty knife so that the openings of the production tooling were completely filled. The coated production tooling was left at room temperature in air to dry. The shaped particles were removed from the production tooling by passing it over an ultrasonic horn.

[0122] Shaped particles made from LDH are produced from LDH-OH powder and then undergo neutralization and conversion to chloride salt (LDH-Cl) by treatment, as is known in the art, with either hydrochloric acid or a mixture of acetic acid and lithium chloride or other combinations of acids and chloride salts.

[0123] Shaped particles can alternatively be produced from LDH-Cl powder where the neutralization and conversion to the chloride salt of LDH has occurred, as is known in the art, prior to the shaping of the particle. Example 20

[0124] 2.01 g LDH powder prepared in example 23 was added to 133.31 g of heated LiCl solution (200 ppm Li) and agitated with a rocker table at 60˚C. Samples of the brine supernatant were taken and analyzed for lithium content. The lithium content of the supernatant increased overtime indicating removal of lithium from the LDH. The sample was washed with deionized water. A portion, 0.51 g, of the washed LDH powder was then exposed to heated multicomponent brine made from LiCl, NaCl, KCl, CaCl2, B(OH)3and deionized water (400 ppm Li, 40,000 ppm Na, 16,000 ppm K, 30,000 ppm Ca, 390 ppm B) and agitated with a rocker table at 60˚C. Samples of the brine supernatant were taken and analyzed for metal ion content by the method described above. The lithium content of the brine decreased indicating LDH adsorption of lithium from the brine. The amount of lithium per gram of sorbent of the adsorption (Qa) or desorption (Qd) step versus time is given in Table 3.

[0125] Table 3. Data from Example 20 QdTime QaTime (mg Li / g sorbent desorbed) (h) (mg Li / g sorbent adsorbed) (h) 0 0 0 0 0.66 0.05 1.70 0.25 1.59 0.25 2.55 0.67 1.79 0.67 2.68 2.00 3.58 1.67 2.81 4.00 4.11 4.33 2.88 6.00 4.64 5.83 Example 21

[0126] 0.99 g LDH-OH granules (from example 15) that had been neutralized and converted to the LDH-Cl form were added to 66.69 g of heated LiCl solution (200 ppm Li) and agitated with a rocker table at 60˚C. Samples of the brine supernatant were taken and analyzed for lithium content. The lithium content of the supernatant increased overtime indicating removal of lithium from the LDH. The sample was washed with deionized water. A portion of the washed LDH granules, 0.51 g, was exposed to 33.34g of heated multicomponent brine made from LiCl, NaCl, KCl, CaCl2, B(OH)3and deionized water (400 ppm Li, 40,000 ppm Na, 16,000 ppm K, 30,000 ppm Ca, 390 ppm B) and agitated with a rocker table at 60˚C. Samples of the brine supernatant were taken and analyzed for metal ion content by the method described above. The lithium content of the brine decreased indicating LDH adsorption of lithium from the brine. The amount of lithium per gram of sorbent of the adsorption or desorption step versus time is given in Table 4.

[0127] Table 4. Data from Example 21 QdTime QaTime (mg Li / g sorbent desorbed) (h) (mg Li / g sorbent adsorbed) (h) 000 00.0670.67 2.35 0.750.47 2.00 2.88 2.00 1.48 3.17 2.94 4.10 1.95 4.33Simulations Simulation Method for Obtaining Permeability

[0128] By modeling the permeability trends observed above, it was possible to confirm expected performance of other geometric shapes (e.g., curved square). The numerical simulation to estimate the permeability of a packed bed of particles involved three steps. First, the technique utilized a particle filling simulation as described in López, A., Vivacqua, V., Hammond, R. and Ghadiri, M., 2020. Analysis of screw feeding of faceted particles by discrete element method, Powder technology, 367, pp.474-486. Second, the geometry was recreated using the position and orientations of each particle from the first step. Third, the fluid flow was determined through the reconstructed packed bed of particles. Such an approach has been successfully demonstrated and reported. See, for example, Bai, H., Theuerkauf, J., Gillis, P.A. and Witt, P.M., 2009. A coupled DEM and CFD simulation of flow field and pressure drop in fixed bed reactor with randomly packed catalyst particles. Industrial & Engineering Chemistrypp.4060-4074 and Fonte, C.B., Oliveira Jr, J.A. and de ALMEIDA, L.C., 2015, December. DEM-CFD coupling: mathematical modelling and case studies using ROCKY-DEM® and ANSYS Fluent®. In Proceedings of the 11th International Conference on CFD in the Minerals and Process Industries, CSIRO, Melbourne, Australia (pp.7-9).

[0129] Shaped particles were dropped into a cylindrical container having a diameter that was at least 8-10 times the length of the particle from a height that is at least 20 times the particle length. This ensured that the results were insensitive to the container size and the drop height. The particles experienced gravitational force and repulsive forces that prevented overlap of the particles. The particles were also dropped with random orientations. These conditions were chosen so that they could replicate packing conditions expected in real-world as best as possible, and the results are expected to provide qualitative changes in packing and permeability expected with changes in particle geometry. Commercialsoftware Ansys Rocky DEM was used to perform this step. An .STL file describing the shape of the particle was supplied for different shapes and Figure 10A-D illustrates some of the representative shapes, e.g., triangular (Example 22), curved triangular (Example 23), curved squares (Example 24), and discs (Comparative Example 8). The geometric surface area to volume ratio was computed for these shapes. Figure 11 shows a snapshot of the packed bed structure for Example 23 during an intermediate timestep during the simulation. Because of numerical tolerances in the simulations, small levels of particle overlap could be observed, and its value was below 5%.

[0130] For step 2, the position and orientation of the particle were exported from Ansys Rocky. Commercial CAD software can be used to recreate a .STEP file describing the packed bed. Commercial software COMSOL Multiphysics with Matlab Livelink was used to automate the process for various particle shapes. The particle volume was subtracted from a cylindrical fluid volume that had a radius, ^^, which was 95% of the radius of the cylinder used for the packing simulations. This further eliminated the errors associated with the edges of the container in the calculation of the permeability. The particles wereshrunk by a factor ^^, where the condition ^1 െ ^^^ ≪ 1 was satisfied. Particle overlap in step(1) causedsharp edges during the meshing process for certain packed beds and shrinking the particles slightlyovercame the problem. A value of ^^ ^ 0.98 was used in the simulations for particles described in Figure10. The bed porosity, ^^, was calculated at this stage of the simulation. The bed porosity was obtained from the ratio of the volume of the fluid divided by the volume of the cylinder of radius R and height, H.The value of the porosity approached a statistically consistent value when ^^ was between ^^^, ^^^ െ ^^^,where ^^ is the particle size and ^^^is the highest extent of the particles in the bed for all shapes studied here. The bed height was not a well-defined quantity because the top surface of a packed bed always exhibited an uneven surface. This would typically not be an issue as long as the bed height was significantly larger than the particle size. However, complexity of the simulations restricted this height. Because the roughness of the top surface of the bed is different for different particles, a bed height termed, ^^∗, given by ^^∗ൌ^^ே^గோమ^^ିఢ^, was used for all systems, where ^^ is the radius of the cylinder, ^^ is the porosity of the bed, ^^^is the number of particles in the simulation, and ^^^is the volume of each particle. The value of ^^∗was suchthat ^^^^ଶ^1 െ ^^^^^∗ represented the number of particles in the bed.

[0131] For step (3), the cylindrical fluid domain mesh generated in step(2) was used for a fluid flow simulation. One of the flat faces was specified with a constant velocity, ^^, the second flat face was specified with zero pressure, and the curved face and all faces of the particle satisfy the no-slip velocity boundary condition. The regime was simulated in the low Reynolds number regime where forces associated with fluid inertia were neglected. The fluid flow equations used to describe the permeability were the Stokes flow equations ^^∇^^^^ ൌ ^^^^,and ^^ ⋅ ^^ ൌ 0,where ^^ is the velocity field in the bed, ^^ is the fluid pressure and ^^ is the viscosity of the fluid. The gradient in the pressure occurred mainly in the packed bed section of the simulation domain. Therefore, the pressure drop between the inlet and outlet of the simulation domain, Δ^^, was used for the calculation of the permeability. The permeability of the bed, ^^, was given by

[0132] The permeability was only a function of the shape of the packed bed of particles. The value of ^^ also scaled with the square of the particle size. This was also confirmed in the simulations.

[0133] In all, the following geometric shapes were analyzed according to the simulated method above: Example (EX) 22 - Simulated triangles having sides with the ratios 1:0.81:0.5. The distance between faces was 1 / 5 of the longest edge. Example (EX) 23 - Simulated curved triangles having a point-to-point length to thickness ratio of 5:1. Example (EX) 24 - Simulated curved squares having (adjacent) point-to-point length to thickness ratio of 2:1. Comparative Example (CE) 7 - Simulated spheres. Comparative Example (CE) 8 - Simulated discs having a diameter to height ratio of 5.

[0134] Plots of the permeability as a function of volumetric surface area for each are provided in FIG.12. Plots of the packed bed porosity as a function of particle size using packed bed simulation is provided in FIG.13. Example 25

[0135] DISPERAL P2 boehmite (8.08 g) obtained from Sasol North America was dispersed in deionized water (72.01 g) by stirring. Lithium titanate, Li4Ti5O12(72.32 g) available from OP-tek was added. During this time SOKALAN CP N40v was added as a dispersant along with 32.97 g of additional water to maintain fluidity of the slurry. The slurry was coated onto a production tooling having shaped mold cavities according to the disclosure of paragraph

[0128] of U.S. Pat. Appln. Publ. No. 2010 / 0146867 (Boden et al.).

[0136] A mold release agent, 1 percent peanut oil in methanol, was used with about 0.5 mg / in2(0.08 mg / cm2) of peanut oil applied to the production tooling having an array of mold cavities. The excess methanol was removed by drying at room temperature. The slurry was forced into the cavities with a putty knife so that the openings of the production tooling were completely filled. The coated production tooling was left at room temperature in air to dry. The shaped particles were removed from the production tooling by passing it over an ultrasonic horn.

[0137] The particles were heat treated to 325 °C for 1.5 hours.Example 26

[0138] Lithium carbonate (18.50 g) and Aeroxide P25 titanium oxide (20.00 g) were added to a jar and mixed together with shaking. The mixture was then heated in a Rapid Temp Furnace from CM Inc. Bloomfield, NJ at a ramp rate of 10 °C / min to 760 °C followed by a 4 hour hold to produce Lithium titanate, Li2TiO3.

[0139] DISPERAL P2 boehmite (4.99 g) obtained from Sasol North America was dispersed in deionized water (49.99 g) by stirring. With stirring, the lithium titanate (4.49 g) was added to 10% boehmite dispersion (4.99 g). During the process 1.76 g of additional water was added to maintain fluidity of the slurry. The slurry was coated onto a production tooling having shaped mold cavities according to the disclosure of paragraph

[0128] of U.S. Pat. Appln. Publ. No.2010 / 0146867 (Boden et al.).

[0140] A mold release agent, 1 percent peanut oil in methanol, was used with about 0.5 mg / in2(0.08 mg / cm2) of peanut oil applied to the production tooling having an array of mold cavities. The excess methanol was removed by drying at room temperature. The slurry was forced into the cavities with a putty knife so that the openings of the production tooling were completely filled. The coated production tooling was left at room temperature in air to dry. The shaped particles were removed from the production tooling by passing it over an ultrasonic horn.

[0141] The particles were heat treated to 325 °C for 1.5 hours. Hypothetical Example (HE) 1

[0142] The lithium manganese oxide can is synthesized by one of the following methods including solid state reaction, sol-gel, hydrothermal or refluxing. This powder is mixed by high shear mixing in a solution containing water and a dispersant 5 or more minutes. The resulting slurry is aged for at least 1 hour before coating. The slurry is coated onto a production tooling having shaped mold cavities according to the disclosure of paragraph

[0128] of U.S. Pat. Appln. Publ. No.2010 / 0146867 (Boden et al.).

[0143] A mold release agent, 1 percent peanut oil in methanol, is used with about 0.5 mg / in2(0.08 mg / cm2) of peanut oil applied to the production tooling having an array of mold cavities. The excess methanol is removed by drying at room temperature. The slurry is forced into the cavities with a putty knife so that the openings of the production tooling were completely filled. The coated production tooling is left at room temperature in air to dry. The shaped particles are removed from the production tooling by passing it over an ultrasonic horn.

[0144] Thus, the present disclosure provides, among other things, a shaped lithium adsorbent particle and separation methods based thereon. Various features and advantages of the present disclosure are set forth in the following claims.

Claims

What is claimed is:

1. A shaped lithium adsorbent particle comprising: a first major surface defined by a first perimeter having at least three edges; a second major surface defined by a second perimeter having the same number of edges as the first perimeter, the second major surface spatially separated from the first major surface and having the same shape as the first major surface; and a peripheral surface comprising a plurality of walls disposed between the first and second major surfaces, the peripheral surface having the same number of walls as the first perimeter has edges, the peripheral surface contiguous with all edges of the first and second perimeters, wherein the peripheral surface intersects the edges of the first and second perimeters and the average radius of curvature at the intersections is no greater than 50 micrometers, wherein the length of the particle is no greater than 5 mm, wherein the length of the particle is at least 2 times greater than the thickness of the particle, and wherein the lithium adsorbent shaped particle comprises a lithium adsorbent material.

2. The shaped lithium adsorbent particle of claim 1, wherein the lithium adsorbent material has the formula LiX^nM(OH)3^mH2O, where X is at least one anionic species, where M is at least one of a trivalent metal ion selected from the group consisting of Al, Ga, In and, optionally, at least one transition metal ion, and where n is selected so that the mole ratio of M to Li is at least 1:

1.

3. The shaped lithium adsorbent particle of claim 2, wherein the at least one transition metal ion is selected from the group consisting of Fe, Ti, Mn, Cr, Co, Ni, Cu, Zn, Zr, Nb, Mo, W, Ag, or combinations thereof.

4. The shaped lithium adsorbent particle of claim 1, wherein the lithium adsorbent material has the formula LixMyOz, where M is a metal ion selected from the group consisting of Ti, Mn, Cr, Co, Ni, Cu, Zn, Zr, Nb, Mo, W, Ag, Sn, Ge, Si, Al, or combinations thereof, and where x, y and z are selected to conserve electrical neutrality.

5. The shaped lithium adsorbent particle of claim 1, wherein the lithium adsorbent material comprises Li4Mn5O12, LiMnO2, Li2MnO2, LiMn2O4, Li2Mn2O4, Li1.6Mn1.6O4,or Li2MnO3, Li2SnO3, LiCuO2, Li3VO4, Li2Si3O7, LiFePO4,LiMnPO4, Li2CuP2O7, H2TiO3, Li4Ti5O12, Li2TiO3, Li4Ti5O12, Li4TiO4, Li7Ti11O24, or combinations thereof.

6. The shaped lithium adsorbent particle of any one of the preceding claims, wherein the first major surface and second major surface are the same size.

7. The shaped lithium adsorbent particle of any one of claims 1 to 5, wherein the second major surface is dimensionally smaller than the first major surface, and the plurality of walls of the peripheral surface form a dihedral angle of less than 90° with the first major surface.

8. The shaped lithium adsorbent particle of any one of claims 1 to 7, wherein at least one edge of the first perimeter extends inwardly as a concave monotonic curve and terminates at two corners defining first and second acute interior angles, wherein the first acute interior angle is in the range of from 35 to 55 degrees, wherein the second acute interior angle is in the range of from 35 to 55 degrees, wherein the inwardly extending edge has a maximum depth that is at least 5 percent of the maximum dimension of the shaped lithium adsorbent particle parallel to the maximum depth.

9. The shaped lithium adsorbent particle of any one of claims 1 to 8, wherein all edges of the first perimeter extend inwardly as a concave monotonic curve and each terminates at two sharp corners defining first and second acute interior angles, wherein the first acute interior angle is in the range of from 35 to 55 degrees, wherein the second acute interior angle is in the range of from 35 to 55 degrees, wherein each of the inwardly extending edges has a maximum depth that is at least 5 percent of the maximum dimension of the shaped lithium adsorbent particle parallel to the maximum depth.

10. The shaped lithium adsorbent particle of any one of claims 1 to 9 where at least one of the first or second major surfaces is concave.

11. The shaped lithium adsorbent particle of any one of claims 1 to 10, wherein the first perimeter has three edges.

12. The shaped lithium adsorbent particle of any one of claims 1 to 11, wherein the first perimeter has four edges.

13. The shaped lithium adsorbent particle of any one of claims 1 to 12, wherein the first perimeter has a shape selected from triangles, squares, rectangles, pentagons, hexagons, diamonds, stars, or truncated versions thereof.

14. A method of making the shaped lithium adsorbent particle of any one of claims 1 to 13, the method comprising:adding a lithium adsorbent dispersion to a mold having one or more shaped cavities; drying the lithium adsorbent dispersion to form shaped lithium adsorbent particles; and removing the shaped lithium adsorbent particles from the mold.

15. A device comprising: a reservoir having a fluid inlet and a fluid outlet; and a plurality of the shaped lithium adsorbent particles from any one of claims 1 to 13 disposed within the reservoir.

16. The device claim 15, wherein the reservoir is a vertical column and the plurality of shaped lithium adsorbent particles within the column have a void volume of 35-80 percent.

17. The device of claim 15 or claim 16, wherein the permeability of a fluid through the plurality of shaped lithium adsorbent particles is at least 1.5 times greater, at least 2 time greater, or at least 3 times greater than the permeability of the same fluid through a batch of spherical particles, each spherical particle having the same composition and volumetric surface area as the shaped lithium adsorbent particles.

18. A method of separating lithium ions from an aqueous solution comprising: disposing the shaped lithium adsorbent particles in any one of claims 1 to 13 in a reservoir having a fluid inlet and a fluid outlet; contacting a solution comprising lithium ion with the shaped lithium adsorbent particles in the reservoir; and separating at least a portion of the lithium ion from the solution.

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