Membranes having reduced dimensional properties

Abstract

A membrane is described that includes a feed inlet, a retentate outlet, and a permeate outlet. The membrane further includes a membrane interface portion that includes a plurality of feed flow channels fluidly connected to the feed inlet and the retentate outlet, and a plurality of permeate flow channels fluidly connected to the permeate outlet, the membrane interface portion operable to allow fluid communication between the feed flow channels and the permeate flow channels through the membrane portion. The membrane interface portion includes a decrease in dimensional characteristics from the feed inlet to the retentate outlet such that the membrane interface portion is operable to generate a higher cross-flow velocity in the membrane portion toward the retentate outlet. A water treatment module including the membrane and a process for manufacturing the membrane are also provided.

Description

[Technical field]

[0001] The present invention relates to membranes, more particularly to membranes for water treatment. [Background technology]

[0002] Traditional water treatment methods such as chemical disinfection, solar disinfection, boiling, sedimentation and distillation are not sufficient to meet the drinking water needs of the world's population at low cost. To address this issue, more advanced technologies such as pressure-driven membrane-based water treatment technologies, which generally include ultrafiltration (UF), microfiltration (MF), nanofiltration (NF) and reverse osmosis (RO), have been established and industrialized. By offering the advantages of avoiding heat input, application of chemical additives and reducing media regeneration, these methods have significantly improved the water treatment industry.

[0003] Membrane filtration has advantages over other water treatment technologies due to, in principle, the absence of significant heat input, fewer chemical additives, and a lower need for regeneration of spent media. Pressure-driven membrane processes are the most widely applied membrane technology in water treatment for the removal of particulate matter, ions, microorganisms, bacteria, and natural organic matter, covering different applications from waste treatment from the food and oil industries to seawater desalination.

[0004] Typically, separation membranes are classified according to their characteristic pore size (pore diameter) or intended use. Microfiltration membranes (MF) with pore sizes ranging from 0.1 μm to 100 μm can be used to remove bacteria, cysts, yeast cells, suspended particles, pigments, and asbestos. Ultrafiltration membranes (UF) with pore sizes ranging from 0.01 μm to 0.1 μm can be used to remove proteins, colloidal particles, and viruses. Nanofiltration membranes (NF) with pore sizes ranging from 0.001 to 0.01 μm can be used to select multivalent ions, dissolved compounds, medium-sized organic molecules, small proteins, and small colloidal particles. Reverse osmosis membranes (RO) with pore sizes smaller than 0.001 μm can be used to remove ions and small organic molecules.

[0005] However, when using current membrane systems for water treatment, a layer of high concentration of particles forms adjacent to the membrane surface, which creates a resistance for water to permeate through the membrane. Over time, the concentration of this layer increases, which further increases the resistance to water permeating through the membrane, thereby causing a decrease in flux over time. Furthermore, the ongoing flux continuously increases the concentration of particles near the membrane. After a while, the concentration of particles at the membrane surface becomes so high that there is a steep concentration gradient near the membrane surface. This leads to diffusion of particles from the membrane surface into the bulk feed stream. Eventually, an equilibrium is reached in the transport rate of particles due to convection (from the bulk feed stream to the membrane surface) and diffusion (from the membrane surface to the bulk feed stream), and thus the flux stabilizes, but at a level significantly lower than the initial flux. This phenomenon is known as concentration polarization (CP), and the region of high concentration adjacent to the membrane is called the concentration polarization (CP) layer. The CP layer is typically reversible and only present when flow is established, but over time it can become compact and begin to irreversibly foul the membrane, further affecting flux.

[0006] Means of producing new clean water resources and protecting existing water resources at lower capital and operating costs require improved and tunable fouling resistance, higher yields with lower energy input, longer life, and improved chemical and mechanical resistance. Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, improved membrane systems and treatment technologies for efficient water treatment with satisfying properties are desirable.

[0008] It is therefore an object of aspects of the present invention to address one or more of the above or other problems. [Means for solving the problem]

[0009] According to a first aspect of the invention, there is provided a membrane comprising: A feed liquid inlet; a retentate outlet; and a permeate outlet; a membrane interface portion including a plurality of feed flow channels fluidly connected to the feed inlet and the retentate outlet, and a plurality of permeate flow channels fluidly connected to the permeate outlet, the membrane interface portion operable to allow fluid communication between the feed flow channels and the permeate flow channels through the membrane portion; wherein the membrane interface portion includes a decreasing dimensional characteristic from the feed inlet to the retentate outlet such that the membrane interface portion is operable to generate a higher cross-flow velocity at the membrane portion toward the retentate outlet.

[0010] According to a second aspect of the invention there is provided a membrane obtainable by additive manufacturing, preferably a membrane according to the first aspect of the invention obtainable by additive manufacturing.

[0011] According to a third aspect of the invention there is provided a method for preparing a membrane, preferably a membrane according to the first or second aspect of the invention, comprising the steps of: a. Producing said membrane by additive manufacturing A method is provided that includes:

[0012] According to a fourth aspect of the present invention, there is provided a method for separating components from a feed stream composition, comprising the steps of: a. introducing a feed stream composition to a membrane according to any of the first to third aspects of the present invention such that the feed stream contacts the membrane; b. separating at least a portion of the components from said feed stream through said membrane into a permeate stream composition; A method is provided that includes:

[0013] According to a fifth aspect of the present invention, there is provided a water treatment module including a membrane according to any one of the first to third aspects of the present invention.

[0014] Advantageously, by employing a membrane according to any of the first to fifth aspects of the invention in which the membrane interface portion proximal to the feed inlet has a larger average dimensional characteristic than the membrane interface portion distal to the feed inlet, the cross-flow velocity of the feed stream (and therefore the shear on the membrane) may be enhanced towards the distal end of the membrane. The increased shear at the membrane surface may improve the flux towards the distal end of the membrane and compensate for the depleted pressure in this region, thus generating a more uniform flux across the length of the membrane. Furthermore, the increased cross-flow velocity towards the distal end of the membrane may also more effectively remove particles near the membrane surface, thus making this region less susceptible to contamination (fouling), which is particularly advantageous considering that this region may have a lower pressure.

[0015] The reduced dimensional properties of the present invention may also result in a lower pressure drop across the membrane compared to a membrane that has a uniform value from the proximal to the distal end for the same amount of flux and feed flow rate.

[0016] Advantageously, the membranes of the present invention may require less energy per unit volume of permeate produced, known as the specific energy consumption (SEC), compared to that required for a membrane that has a uniform value from the proximal end to the distal end for the same amount of flux and feed flow rate.

[0017] As used herein, "closer to the feed inlet," "towards the feed inlet," or "proximal end," etc., may mean with respect to the distance along the flow path of the feed stream from the feed inlet.

[0018] As used herein, "closer to the retentate outlet," "towards the retentate outlet," or "distal," etc., may mean with respect to the distance along the flow path of the feed stream from the retentate outlet.

[0019] It will be appreciated that a portion of the feed flow path may extend laterally, but the overall feed flow direction may be from a first end of the membrane to a second substantially opposite end of the membrane. In this manner, the membrane may be considered to have an overall feed flow axis (e.g., in the Z direction). The membrane may include a feed inlet disposed toward the first end of the membrane and may have a retentate outlet and / or a permeate outlet at the second end of the membrane. The first and second ends may be at substantially opposite longitudinal ends of the membrane. Thus, the overall feed flow axis may extend along the longitudinal length of the membrane.

[0020] The membrane may include a transverse axis extending substantially transversely (eg, in the X, Y direction) to a general feed flow axis.

[0021] A feed inlet may refer to a channel operable to deliver a feed stream to a membrane interface portion. A feed inlet may not allow direct fluid communication with a permeate outlet.

[0022] A retentate outlet may refer to a channel operable to carry a retentate stream away from the membrane interface portion. A retentate outlet may not allow direct fluid communication with a permeate outlet.

[0023] A permeate outlet may refer to a channel operable to carry a permeate stream away from the membrane interface portion. A permeate outlet may not allow direct fluid communication with a feed inlet.

[0024] The unit cells may abut, such as by being integrally formed to form a continuous structure. The unit cells may be integrally formed by additive manufacturing.

[0025] The membrane interface portion may include a first unit cell layer and a second unit cell layer, each unit cell layer extending substantially transverse to the direction of feed flow, each unit cell layer including a plurality of unit cells.

[0026] Each unit cell of the first and second layers may include a feed stream channel portion, a permeate stream channel portion, and a membrane portion separating the feed stream portion and the permeate stream portion.

[0027] The feed flow channel portions and permeate flow channel portions of a unit cell may be fluidly connected to the feed flow channel portions and permeate flow channel portions of adjacent unit cells.

[0028] The plurality of unit cells in the first unit cell layer may comprise an average of the same dimensional property that is greater than an average dimensional property in the plurality of unit cells in the second unit cell layer, and the first unit cell layer may be disposed closer to the feed inlet than the second unit cell layer. In such an arrangement, the membrane interface portion may comprise a decrease in dimensional property from the feed inlet toward the retentate outlet such that the membrane interface portion is operable to generate a higher cross-flow velocity at the membrane portion toward the retentate outlet.

[0029] Thus, according to a further aspect of the present invention there is provided a membrane comprising: A feed liquid inlet; a retentate outlet; and a permeate outlet; a membrane interface portion including a plurality of feed flow channels fluidly connected to the feed inlet and the retentate outlet, and a plurality of permeate flow channels fluidly connected to the permeate outlet, the membrane interface portion operable to allow fluid communication between the feed flow channels and the permeate flow channels through the membrane portion; the membrane interface portion includes a first unit cell layer and a second unit cell layer, each unit cell layer extending substantially transverse to a direction of feed liquid flow, each unit cell layer including a plurality of unit cells; each of the unit cells of the first and second layers includes a feed stream channel portion, a permeate stream channel portion, and a membrane portion separating the feed stream portion and the permeate stream portion; the feed flow channel portion and the permeate flow channel portion of a unit cell are fluidly connected to the feed flow channel portion and the permeate flow channel portion of an adjacent unit cell; the plurality of unit cells in the first unit cell layer include an average of a dimensional characteristic that is greater than an average dimensional characteristic in the plurality of unit cells in the second unit cell layer; The first layer of unit cells is disposed closer to the feed inlet than the second layer of unit cells. A membrane is provided.

[0030] The following features may apply to any of the first to fifth or further aspects of the present application.

[0031] An "average dimensional property" may be an average calculated from the respective values ​​in each unit cell of a layer. Such values ​​may be measured by any suitable method known to one of skill in the art. It will be apparent that the unit cells of a unit cell layer may also have a variation in the dimensional property relative to other unit cells of the layer. The variation between unit cells of the same unit cell layer may be less than the average variation of the dimensional property between different unit cell layers, e.g., at least 10% less, at least 25% less, or at least 30% less.

[0032] The first unit cell layer may be operable to experience a higher transmembrane pressure (TMP) than the second unit cell layer due to its proximity to the feed inlet compared to the second unit cell layer.

[0033] The first unit cell layer may be the first unit cell layer at the membrane interface. Thus, the first unit cell layer may be directly adjacent to the feed inlet. The second unit cell layer may be the last unit cell layer at the membrane interface. Thus, the second unit cell layer may be directly adjacent to the retentate outlet.

[0034] The membrane interface portion may include a plurality of unit cell layers, with each subsequent, but not necessarily immediately adjacent, plurality of unit cells within a unit cell layer extending from proximal to the feed inlet to distal to the feed inlet having decreasing average dimensional properties. As used herein, "plurality" with respect to the number of unit cell layers may mean at least 3, e.g., at least 6, or at least 10. Thus, the membranes of the present invention may provide a gradient of decreasing dimensional properties extending from a highest level proximal to the feed inlet to a lower level distal to the feed inlet.

[0035] The multiple unit cells of the first and / or second unit cell layers may be in the form of a periodically repeating unit cell shape.

[0036] As used herein, "periodically repeated unit cell shapes" may mean that the repeating unit cells have substantially the same three-dimensional shape. However, the unit cells may independently have differences in size of dimensional properties such as overall size, wall thickness, and / or void space size. For example, the shapes may be subject to scaling, whether in one or more dimensions, with respect to overall size, wall thickness, and / or void space. The lateral and / or feed flow direction dimensions of the shapes may be scaled to provide different lateral and / or feed flow direction aspect ratios while maintaining substantially the same three-dimensional shape.

[0037] As used herein, "plurality" with respect to the number of unit cells may mean at least three, for example, at least five, at least ten, or at least fifteen.

[0038] The membrane interface portion includes a decreasing dimensional characteristic from the feed inlet toward the retentate outlet such that the membrane interface portion is operable to generate a higher cross-flow velocity in the membrane portion toward the retentate outlet.

[0039] The dimensional characteristic may be a dimension extending along an overall feed flow directional axis and / or a dimension extending along a transverse axis, e.g., an average overall feed flow directional aspect ratio and / or an average transverse (X and Y) aspect ratio.

[0040] As used herein, the "overall feed flow direction aspect ratio" may be defined as the ratio of the overall feed flow direction size (Z direction) of the unit cells to the average lateral cell size (average of the sizes in the X and Y directions) of the unit cell layer having the largest average unit cell lateral dimension at the membrane interface. Thus, the average lateral cell size of the unit cell layer having the largest average unit cell lateral dimension at the membrane interface may be the reference point from which the aspect ratios of further unit cell layers are calculated. The "lateral aspect ratio" may be defined as the ratio of the average lateral size (average of the sizes in the X and Y directions) of the unit cells to the average lateral unit cell size (average of the sizes in the X and Y directions) of the unit cell layer having the largest average unit cell lateral dimension at the membrane interface.

[0041] Thus, the "global feed flow aspect ratio" may be a measure of the elongation due to scaling in the feed flow (Z) direction, with lower aspect ratios corresponding to less elongation of the membrane interface portion. Similarly, the "lateral" aspect ratio may be a measure of the scaling of the membrane interface portion in the lateral (X and / or Y) directions, e.g., the inward scaling of the membrane interface portion.

[0042] The difference in the aspect ratios in the global feed flow direction between the first and second unit cell layers may be operable to increase the average flow path that the feed must traverse over the same distance along the global feed flow direction axis. Thus, for the same flow rate, the cross-flow velocity in the second unit cell layer may be higher. The difference in the lateral aspect ratios between the first and second unit cell layers may also be operable to reduce the volume and cross-sectional area of ​​the feed channels in the second unit cell layer compared to the volume and cross-sectional area of ​​the feed channels in the first unit cell layer, and thus, considering incompressible flow, the feed flow must accelerate to conserve mass (and volume), and thus the average velocity in the second unit cell layer may increase. As a result, the second unit cell layer may have a higher cross-flow velocity at the surface of the membrane portion on the feed flow side compared to the first unit cell layer. The shear at the membrane surface may be positively affected by the higher cross-flow velocity, and therefore the average value of the shear at the membrane surface may be higher in the second unit cell layer compared to the first unit cell layer, which may help to break down the concentration polarization layer more effectively in this region, thereby reducing the hydraulic resistance that the concentration polarization layer may cause, which may allow more permeate to pass through the membrane portion.

[0043] The first unit cell layer may include a higher average lateral aspect ratio than the second unit cell layer.

[0044] The first unit cell layer may include an average lateral aspect ratio of at least 0.2, such as at least 0.5. The first unit cell layer may include an average lateral aspect ratio of up to 1. The first unit cell layer may include an average lateral aspect ratio of 0.2 to 1, such as 0.5 to 1.

[0045] The second unit cell layer may include an average lateral aspect ratio of at least 0.1, such as at least 0.4. The second unit cell layer may include an average lateral aspect ratio of up to 0.99, such as up to 0.8. The second unit cell layer may include an average lateral aspect ratio of 0.1 to 0.99, such as 0.4 to 0.8.

[0046] The first unit cell layer may include a higher average feed flow direction aspect ratio than the second unit cell layer.

[0047] The first unit cell layer may comprise an average feed flow direction aspect ratio of at least 0.5. The first unit cell layer may comprise an average feed flow direction aspect ratio of up to 10, such as up to 4. The first unit cell layer may comprise an average feed flow direction aspect ratio of 0.5 to 10, such as 0.5 to 4.

[0048] The second unit cell layer may comprise an average feed flow direction aspect ratio of at least 0.1, such as at least 0.3. The second unit cell layer may comprise an average feed flow direction aspect ratio of up to 5, such as up to 3. The second unit cell layer may comprise an average feed flow direction aspect ratio of 0.1-5, such as 0.3-3.

[0049] The aspect ratio of the membrane in the lateral and / or feed flow direction may decrease from the portion of the membrane interface proximal to the feed inlet to the portion of the membrane interface distal to the feed inlet, e.g., the aspect ratio of the membrane may decrease from the feed inlet to the retentate outlet of the membrane, e.g., through multiple unit cell layers. Advantageously, this arrangement may establish a gradient in the cross-flow velocity in the membrane such that the cross-flow velocity at the distal end is enhanced and the resulting high shear helps improve flux in this region, compensating for the depleted transmembrane pressure and generating more uniform flux.

[0050] A dimensional property, such as an aspect ratio, may vary along a membrane interface partial unit cell layer according to a gradient, such as along a linear gradient, along an exponential gradient, and / or along a polynomial gradient.

[0051] The reduction in the dimensional property may be a reduction in wall thickness at the membrane interface, such as a reduction in wall thickness at the membrane portion. The second unit cell layer may include an average wall thickness that is less than the first unit cell layer.

[0052] The membrane interface divides the volume into a feed region and a permeate region, and the transmembrane pressure (TMP) is governed by the average of the feed and retentate pressures, which is the force that drives the flow from the feed channel to the permeate channel through the membrane interface. Advantageously, a thinner membrane wall in the second unit cell layer distal to the feed inlet may help increase the flux in the distal region. The transmembrane pressure may decrease from the proximal to the distal end of the membrane interface portion, and a larger thickness may be required toward the proximal end for structural support, while a smaller thickness toward the distal end may be sufficient. Thus, the decrease in thickness from the proximal to the distal end may generate more flux, even though this region has a depleted pressure, because the thinner walls exhibit a lower hydraulic resistance.

[0053] The first unit cell layer may have an average thickness ratio of at least 0.5, such as at least 0.8. The first unit cell layer may have an average thickness ratio of up to 1. The first unit cell layer may have an average thickness ratio of 0.5 to 1, such as 0.8 to 1.

[0054] The first unit cell layer may have an average wall thickness of 0.3 mm or more, for example 0.5 mm or more. The first unit cell layer may have an average thickness of 5 mm or less, for example 3 mm or less. The first unit cell layer may have an average thickness of 0.3 mm to 5 mm, for example 0.5 to 3 mm.

[0055] The second unit cell layer may have an average thickness ratio of at least 0.1, such as at least 0.4. The second unit cell layer may have an average thickness ratio of up to 0.99, such as up to 0.8. The second unit cell layer may have an average thickness ratio of 0.1 to 0.99, such as 0.4 to 0.8.

[0056] The second unit cell layer may have an average wall thickness of 0.2 mm or more, for example 0.4 mm or more. The second unit cell layer may have an average thickness of 4 mm or less, for example 2 mm or less. The second unit cell layer may have an average thickness of 0.2 mm to 4 mm, for example 0.4 to 2 mm.

[0057] As used herein, "thickness ratio" may be defined as the ratio of the average thickness of the unit cell wall to the average thickness of the unit cell layer having the largest average unit cell wall thickness dimension at the membrane interface.

[0058] The unit cells are suitably fluidly connected such that a feed flow can pass from the feed flow portion of one unit cell to the feed flow portion of another adjacent unit cell, and / or a permeate flow can pass from the permeate flow portion of one unit cell to the permeate flow portion of another unit cell.

[0059] The periodically repeating unit cell shape may include a triple periodic unit cell shape.

[0060] The periodically repeating unit cell geometry may include a gyroid structure having a bias length that varies with a gradient, preferably a linear gradient; a gyroid structure having a wall thickness that varies with a (linear) gradient; and / or a diamond lattice structure having a strut thickness that varies with a (linear) gradient.

[0061] The unit cells may have a maximum dimension of 0.5 mm or more, such as 0.7 mm or more, or 0.9 mm or more. The unit cells may have a maximum dimension of 100 mm or less, such as 70 mm or less, or 50 mm or less. The unit cells may have a maximum dimension of 0.5 to 100 mm, such as 0.7 to 70 mm, or 0.9 to 50 mm.

[0062] The shape of the unit cell may be a diamond structure, a cubic structure, a fluorite structure, an octet structure, a Kelvin cell structure, an iso-truss structure, a hexagonal prism diamond structure, a truncated tube structure, a truncated octahedral structure, a Weaire-Phelan structure, a body-centered cubic structure, and / or a face-centered cubic structure.

[0063] The triple periodic unit cell may comprise a triple periodic minimal surface unit cell selected from, for example, a gyroid structure, a schwarz P structure, a schwarz D structure, a schwarz CLP structure, a schwarz H structure, a split P structure, a neobius structure, or a double gyroid structure.

[0064] The internal void volume of the feed channel at the membrane interface may be greater than the internal void volume of the permeate channel. The average width of the feed flow channel of the unit cell may be greater than the average width of the permeate flow channel of the unit cell.

[0065] The ratio of the average width of the feed flow channel portion of the unit cells to the average width of the permeate flow channel portion of the unit cells may be at least 1:1, such as at least 1.1:1. The ratio of the average width of the feed flow channel portion of the unit cells to the average width of the permeate flow channel portion of the unit cells may be up to 3:1, such as up to 1.8:1. The ratio of the average width of the feed flow channel portion of the unit cells to the average width of the permeate flow channel portion of the unit cells may be from 1:1 to 3:1, such as from 1.1:1 to 1.8:1.

[0066] A unit cell may include a feed flow channel portion having an average width of 2 mm or more, e.g., 5 mm or more. A unit cell may include a feed flow channel portion having an average width of 50 mm or less, e.g., 20 mm or less. A unit cell may include a feed flow channel portion having an average width of 2-50 mm, e.g., 5-20 mm.

[0067] A unit cell may include a permeate flow channel portion having an average width of 1.5 mm or more, such as 3 mm or more. A unit cell may include a permeate flow channel portion having an average width of 40 mm or less, such as 15 mm or less. A unit cell may include a permeate flow channel portion having an average width of 1.5 to 40 mm, such as 3 to 15 mm.

[0068] The membrane may have a tensile strength operable to withstand a feed application pressure of 0.5 MPa or more, such as 1 MPa or more or 2 MPa or more, optionally in the range of 2 MPa to 200 MPa. The tensile strength of the ceramic membrane may be measured according to ASTM C1273-18.

[0069] The membrane may have an open porosity of at least 10%, such as at least 20%, for example at least 30%, such as at least 40%, for example at least 50%. The membrane may have an open porosity of 10% to 60%, such as 15% to 50%, for example 20% to 40%. Nanofiltration membranes may have an open porosity of 10% to 40%, for example 10% to 30%.

[0070] As used herein, "open porosity" may be the volume of pores that are interconnected from one side of the membrane to the other, for example, from the feed side of the membrane to the permeate side of the membrane, also known as "connected porosity" or "effective porosity." Open porosity may be measured by optical and electronic inspection of a cross section of the membrane using any suitable microscopy technique. Open porosity may be measured by capillary flow porometry (used for 50 nm to 500 μm). Open porosity may be measured by Nano-Perm Porometer (used for 0.5 to <50 nm).

[0071] The membrane may have a closed porosity of 0-90%, such as 10-60%, such as 20-40%. Closed porosity is the volume of voids that either have no connection to both sides of the membrane, e.g., no connection to the feed inlet of the membrane or the permeate outlet of the membrane, or have connections to only one side but not the other (also known as dead-end pores). Closed porosity may be measured by optical and electronic inspection of a cross-section of the membrane using any suitable microscopy technique, such as transmission electron microscopy (TEM) and / or scanning electron microscopy (SEM).

[0072] The membrane may have a total porosity (also known as "bulk porosity") of at least 40%, such as at least 50%, for example at least 60%. Total porosity is the sum of open and closed porosity. Total porosity may be measured by optical and electronic inspection of a cross-section of the membrane using any suitable microscopy technique. Total porosity may be measured by the Archimedes porosity determination method.

[0073] The membrane may be a microfiltration membrane. The microfiltration membrane, or a mode therein in the multi-model pore distribution, may include pore sizes from 0.01 μm to 10 μm, such as from 0.05 μm to 5 μm, for example about 0.1 μm. The microfiltration membrane, or a mode therein in the multi-model pore distribution, may have a pore size distribution including a D50 pore size of 0.01 μm to 10 μm, for example from 0.05 μm to 5 μm, for example about 0.1 μm. The microfiltration membrane, or a mode therein in the multi-model pore distribution, may have a pore size distribution including a D10 pore size of at least 0.01 μm, for example at least 0.05 μm. The microfiltration membrane, or a mode therein in the multi-model pore distribution, may have a pore size distribution including a D90 pore size of up to 10 μm, for example up to 5 μm. The microfiltration membrane may be operable to remove particles having an average particle size of at least 0.1 μm from a liquid stream.

[0074] The membrane may be an ultrafiltration membrane. The ultrafiltration membrane, or a mode therein in the multi-model pore distribution, may include pore sizes from 5 nm to 1 μm, such as 5 nm to 0.1 μm, such as about 0.01 μm. The ultrafiltration membrane, or a mode therein in the multi-model pore distribution, may have a pore size distribution including a D50 pore size of 5 nm to 1 μm, such as 5 nm to 0.1 μm, such as about 0.01 μm. The ultrafiltration membrane, or a mode therein in the multi-model pore distribution, may have a pore size distribution including a D10 pore size of at least 5 nm. The ultrafiltration membrane, or a mode therein in the multi-model pore distribution, may have a pore size distribution including a D90 pore size of up to 1 μm, such as up to 0.1 μm, such as up to 0.01 μm. The ultrafiltration membrane may remove particles of 0.01 μm or larger from the liquid stream.

[0075] The membrane may be a nanofiltration membrane. The nanofiltration membrane, or a mode therein in the multi-model pore distribution, may comprise pore sizes from 0.1 nm to 100 nm, such as from 0.5 nm to 50 nm, such as from 1 nm to 10 nm, such as from 1 nm to 2 nm, or from 2 to 10 nm. The nanofiltration membrane, or a mode therein in the multi-model pore distribution, may have a pore size distribution comprising a D50 pore size from 0.1 nm to 100 nm, such as from 0.5 nm to 50 nm, such as from 1 nm to 10 nm, such as from 1 nm to 2 nm, or from 2 to 10 nm. The nanofiltration membrane, or a mode therein in the multi-model pore distribution, may have a pore size distribution comprising a D10 pore size of at least 0.1 nm, such as at least 0.5 nm, such as at least 1 nm, such as at least 2 nm. The nanofiltration membrane, or a mode therein in a multi-mode pore distribution, may have a pore size distribution including a D90 pore size of up to 100 nm, such as up to 50 nm, such as up to 10 nm, such as up to 2 nm. The nanofiltration membrane may remove particles of 1 nm or larger, such as 2 nm or larger, from a liquid stream.

[0076] The pore size of the ceramic membrane may be measured by any suitable technique known in the art. The pore size of the ceramic membrane may be measured by gas permeation based on gas flow through a porous sample. The pore size of the ceramic membrane (used for 5 nm to 1 mm) may be measured by mercury intrusion porosimetry using NIST standards. The pore size of the ceramic membrane (used for 0.5 nm to <5 nm) may be measured by nitrogen adsorption at 77 K using the BJH or HK method as appropriate.

[0077] The membrane may be a ceramic membrane, a metal membrane and / or a plastic membrane.

[0078] The ceramic membrane may be formed from any suitable material, and may include alumina, aluminum nitride, aluminum oxide, barium titanate, β-tricalcium phosphate, biological ceramic, bismuth, boron carbide, carbide, hydroxyapatite, iron oxide, magnesium silicate, nitride, oxide, aluminum silicon, silica, silicon carbide, silicon dioxide, silicon nitride, titanate, titanium dioxide, yttrium carbonate, YSZ (yttria stabilized zirconia), zinc oxide, zirconate, zirconia and / or zirconium, or mixtures thereof.

[0079] A feed inlet may refer to a channel operable to deliver a feed stream to a membrane interface portion. A feed inlet may not allow direct fluid communication with a permeate outlet.

[0080] A retentate outlet may refer to a channel operable to carry a retentate stream away from the membrane interface portion. A retentate outlet may not allow direct fluid communication with a permeate outlet.

[0081] The permeate outlet may refer to a channel operable to carry the permeate flow away from the membrane interface portion. The permeate outlet may not allow direct fluid communication with the feed inlet. The membrane of the present invention may be obtainable by an additive manufacturing process. The additive manufacturing technique may be any suitable 3D printing technique. For example, the membrane disclosed herein may be printed using bath photopolymerization techniques such as stereolithography (SLA); digital light processing; two-photon polymerization; two-color photopolymerization; inkjet printing; binder jet printing; direct ink writing; three-dimensional printing; selective laser sintering; selective laser melting; laminated object manufacturing and / or fused deposition modeling.

[0082] The membrane of the present invention may be obtainable by digital light processing or binder jet printing.

[0083] The process for producing the membrane of the present invention by additive manufacturing is as follows: a. providing a layer of powder on a powder bed; b. selectively depositing a binder onto the layer of powder; c. Repeating steps (a) to (b) to form a 3D printed green body; may include:

[0084] The process for producing the membrane according to the present invention by additive manufacturing comprises the steps of: d. Optionally, post-treating the 3D printed body to form a membrane. It may further include.

[0085] The process for producing the membrane according to the present invention by additive manufacturing comprises the steps of: a. providing a layer of powder on a powder bed; b. selectively combining a portion of the powder with a binder comprising nanoparticle and / or microparticle precursors; Optionally, forming said nanoparticle and / or microparticle precursors into nanoparticles and / or microparticles; c. Repeating steps (a) to (b) to form a 3D printed body. Optionally, forming said nanoparticle and / or microparticle precursors into nanoparticles and / or microparticles. wherein the nanoparticle and / or microparticle precursors are formed into nanoparticles and / or microparticles during the manufacture of the membrane.

[0086] The process for producing the membrane according to the present invention by additive manufacturing comprises the steps of: d. Optionally, post-processing the 3D printed body to form a film, and optionally forming the nanoparticle and / or microparticle precursors into nanoparticles and / or microparticles in a further post-processing step. It may further include.

[0087] The membrane may be manufactured by the additive manufacturing processes disclosed herein.

[0088] After selectively binding a portion of the powder, the powder bed may be lowered and a further layer of powder is spread on top of the previous layer. The bed may be lowered a distance of a layer thickness. This process may be repeated until the entire compact is produced. The compact is formed from the powder in all layers bound together by the binder. Powder that is not selectively bound does not form part of the compact.

[0089] The process of additive manufacturing may provide multiple compacts in a single powder bed.

[0090] The powder bed may include a heating portion, such as a heated powder bed. The heated powder bed may be suitable for maintaining the powder on the powder bed at an elevated temperature during the 3D printing process. The heated powder bed may maintain the ceramic powder and binder at an elevated temperature during the 3D printing process. The heated powder bed may be operable to increase the temperature of the 3D printed part during the 3D printing process. The heated powder bed may heat the bed and / or said part to at least 50°C, such as at least 80°C, such as at least 100°C. The heated powder bed may heat the bed and / or said part up to 400°C, such as up to 350°C, such as up to 300°C. The heated powder bed may heat the bed and / or said part to between 50 and 400°C, such as between 80 and 350°C, such as between 100 and 300°C. The heating portion may include a heater system located below the powder bed such that the bed itself is directly heated or located proximate to the powder bed such that the bed is indirectly heated.

[0091] The process may further include heating the powder on the powder bed. The process may further include heating the powder on the powder bed during and / or after each application of the binder in step (b) of the process. Steps a), b) and / or c) of the process may all be completed while the bed is at an elevated temperature. The high bed temperature during 3D printing advantageously improves the structural properties (e.g., tensile strength) of the 3D printed body, which may improve the ability of the 3D printed body to function as a membrane.

[0092] Optional post-treatment of the 3D printed body in step (d) of the above process may include de-powdering the 3D printed body. De-powdering is the removal of excess powder that is not bound to the binder and is not part of the 3D printed body. Excess powder may be removed from the 3D printed body in a de-powdering process that may include agitating / shaking and / or exposing to an air stream.

[0093] The post-treatment step discussed herein may be a degreasing (debinding) step. The degreasing step may be a thermal degreasing step and / or a solvent degreasing step.

[0094] The thermal debinding step may involve heating the compact at atmospheric pressure in an oxidizing or non-oxidizing atmosphere or under vacuum. The temperature, rate and duration of heating may be controlled such that the binder is removed without affecting the particle packing sequence or introducing any new defects into the body.

[0095] The thermal debinding step may comprise heating the compact to at least 200° C., such as at least 300° C., for example at least 400° C. The thermal debinding step may comprise heating the compact up to 1000° C., for example up to 800° C., for example up to 600° C. The thermal debinding step may comprise heating the compact to 200-1000° C., for example 300-800° C., for example 400-600° C.

[0096] Step (d) in the above process may also include an infiltration step, which is the further addition of additional binder that may be used to increase mechanical strength.

[0097] Step (d) in the above process may also include a surface smoothing process, which may be completed by any suitable technique known in the art, such as abrasive flow machining, in which a fluid containing an abrasive, such as a polymer and silicon carbide, is passed through the 3D printed body and / or ceramic membrane to erode any surface irregularities or protrusions.

[0098] The post-treatment step (d) in the above process may comprise heating the 3D printed body to at least 300°C, such as at least 500°C, for example at least 750°C, for example at least 1000°C. The post-treatment step (d) may comprise heating the 3D printed body to up to 1400°C, for example up to 1000°C, for example up to 750°C, for example up to 500°C. The post-treatment step (d) may comprise heating the 3D printed body to 300-1400°C, for example 300-1000°C, for example 500-750°C.

[0099] The post-treatment step (d) in the above process may comprise heating the 3D printed body for at least 20 minutes, such as at least 1 hour, such as at least 4 hours, such as at least 10 hours. The post-treatment step (d) may comprise heating the 3D printed body for up to 40 hours, such as up to 36 hours, such as up to 24 hours, such as up to 10 hours. The post-treatment step (d) may comprise heating the 3D printed body for 1 to 40 hours, such as 4 to 36 hours, such as 10 to 24 hours.

[0100] The resulting post-treated green body is also known as a “brown body.” The green body and / or the brown body may optionally be sintered in a sintering step to form a ceramic membrane.

[0101] The sintering step may comprise heating the green body and / or the degreased body at ambient pressure, in an oxidizing or non-oxidizing atmosphere or under vacuum. The sintering step may comprise heating the green body and / or the degreased body to at least 800°C, such as at least 1000°C, for example at least 1250°C. The sintering step may comprise heating the green body and / or the degreased body to up to 2000°C, such as up to 1800°C, for example up to 1650°C. The sintering step may comprise heating the green body and / or the degreased body to 800-2000°C, such as 1000-1800°C, for example 1250-1650°C.

[0102] The sintering step may include partial sintering of the green body and / or degreased body such that the engineered pore size created by the in-situ formation of nano- and / or microparticles is maintained and / or further refined to the desired final pore size of the membrane.

[0103] The 3D printed body may not require sintering to form a membrane. The 3D printed body may not require heating to form a membrane. The 3D printed body may be a membrane.

[0104] The film may be a ceramic film and the powder in the additive manufacturing processes disclosed herein may be a ceramic powder.

[0105] The ceramic powder may be any suitable ceramic powder used in additive manufacturing. The ceramic powder may include alumina, aluminum nitride, aluminum oxide, barium titanate, β-tricalcium phosphate, biological ceramic, bismuth, boron carbide, carbide, hydroxyapatite, iron oxide, magnesium silicate, nitride, oxide, silicon aluminum, silica, silicon carbide, silicon dioxide, silicon nitride, titanate, titanium dioxide, yttrium carbonate, YSZ (yttria stabilized zirconia), zinc oxide, zirconate, zirconia or zirconium, or mixtures thereof.

[0106] The ceramic powder may comprise a mixture of different ceramic powder compositions.The ceramic powder may comprise a first ceramic powder fraction and a second ceramic powder fraction.

[0107] The ceramic powder may have a volume average size of at least 1 nm, such as at least 10 nm. The ceramic powder may have a volume average size of up to 100 μm, such as up to 10 μm. The ceramic powder may have a volume average size of 1 nm to 100 μm, such as 10 nm to 10 μm. The ceramic powder may have a volume average size of 1 nm to 10 μm.

[0108] The ceramic powder may include a coarse ceramic powder fraction. The coarse ceramic powder fraction may be defined as a ceramic powder having micron-sized particles (i.e., a volume average particle size of at least 0.1 μm). The coarse ceramic powder fraction may have a D10 particle size of at least 0.1 μm.

[0109] The ceramic powder may include a fine ceramic powder fraction. The fine ceramic powder fraction may be defined as a ceramic powder having nano-sized particles (i.e., a volume average particle size of less than 0.1 μm). The fine ceramic powder fraction may have a D90 particle size of up to 0.1 μm.

[0110] The ceramic powder may comprise a mixture of a first ceramic powder fraction, such as a coarse ceramic powder fraction, and a second ceramic powder fraction, such as a fine ceramic powder fraction. The volume ratio of the first ceramic powder fraction to the second ceramic powder fraction, such as the volume ratio of the coarse ceramic powder fraction to the fine ceramic powder fraction, may be at least 1:20, such as at least 1:15, such as at least 1:10, such as at least 1:5, such as at least 1:2. The volume ratio of the coarse ceramic powder fraction to the fine ceramic powder fraction may be up to 20:1, such as up to 15:1, such as up to 10:1, such as up to 5:1, such as up to 2:1.

[0111] The volume ratio of the coarse ceramic powder fraction to the fine ceramic powder fraction may be from 20:1 to 1:20, such as from 15:1 to 1:15, such as from 10:1 to 1:10, such as from 5:1 to 1:5, such as from 1:2 to 2:1. The volume ratio of the coarse ceramic powder fraction to the fine ceramic powder fraction may be from 1:1 to 20:1, such as from 1:1 to 10:1, such as from 5:1 to 10:1, or such as from 2:1 to 10:1.

[0112] The ceramic powder may comprise a free-flowing ceramic material. Preferably, the ceramic powder may be free-flowing. Flowability is the ability of a powder to flow freely, which can aid in uniform powder distribution and thus homogeneous compact and sintered part structure. The flowability of the ceramic powder may be increased by a higher ratio of coarse to fine powder.

[0113] The volume average particle size and particle size distribution of the ceramic powder may be measured by dynamic light scattering technique (DLS) and is suitable for particle sizes of at least 0.3 nm to 10 μm.

[0114] The volume average particle size and particle size distribution of the ceramic powder may be measured by laser light scattering techniques (also known as laser diffraction analysis), suitable for particle sizes of at least 10 μm to 3.5 mm. A Mastersizer 3000 from Malvern Panalytical may be used for laser light scattering.

[0115] The ceramic powder may include a ceramic powder fraction having a generally spherical particle shape.

[0116] The ceramic powder may include a ceramic powder fraction having a generally non-spherical particle shape. The ceramic powder fraction having a non-spherical particle shape may be selected from particles having a cylindrical shape, an angular shape, a spongy shape, an acicular shape, a flake shape, a cubic shape, and / or an agglomerated shape.

[0117] The ceramic powder may include a ceramic powder fraction having a generally spherical particle shape and a ceramic powder fraction having a generally non-spherical particle shape.

[0118] The ceramic powder may comprise a mixture of a first ceramic powder fraction having a generally spherical shape and a second ceramic powder fraction having a cylindrical, spongy, angular, acicular, flaky, cubic, and / or agglomerated shape. The ceramic powder may comprise a mixture of a first ceramic powder fraction having a generally spherical shape and a second ceramic powder fraction having a cylindrical, angular, and / or acicular shape.

[0119] The particle shape of ceramic powders may be measured by transmission electron microscopy (TEM), which provides direct measurement of powders with particle size ranges from 0.1 nm to 5 μm. The particle shape of ceramic powders may be measured by Raman spectroscopy. A Morphologi 4 by Malvern Panalytical may be used to determine the particle shape of ceramic powders with particle size ranges from >5 μm to >1,300 μm using Raman spectroscopy.

[0120] The ceramic powder should have a density of at least 0.5 g / cm 3 , e.g. at least 1 g / cm 3 , e.g. at least 2 g / cm 3 The ceramic powder may have a press density of 10 g / cm 3 Up to, for example, 8g / cm 3 Up to, for example, 6g / cm 3 The ceramic powder may have a pressed density of 0.5 to 10 g / cm. 3 , e.g. 1~8g / cm 3 , e.g. 2~6g / cm 3 The pressed density may be the density of the ceramic powder before sintering and / or the pressed density is the density of the ceramic powder and binder in the form of the 3D printed compact. The pressed density of the ceramic powder may be comparable to the bulk density of the 3D printed compact. The pressed density may be measured using mercury porosimetry.

[0121] The ceramic powder should have a density of at least 0.5 g / cm 3 , e.g. at least 1 g / cm 3, e.g. at least 2 g / cm 3 The ceramic powder may have a fired density of 10 g / cm 3 Up to, for example, 8g / cm 3 Up to, for example, 6g / cm 3 The ceramic powder may have a fired density of 0.5 to 10 g / cm. 3 , e.g. 1~8g / cm 3 , e.g. 2~6g / cm 3 The fired density may be the density of the ceramic powder after sintering, where at least a portion of the binder has been removed. The fired density may be measured using mercury porosimetry or by Archimedes' principle.

[0122] The binder may be dispersed in the interparticulate spaces between the ceramic particles.The binder may be diffused in the interparticulate spaces between the ceramic particles.

[0123] The binder may be dispersed as a binder composition.

[0124] The binder may include a metallic binder, a ceramic binder, and / or a polymeric binder.

[0125] The polymer binder may include acrylates, methacrylates, acrylate polymers (e.g., polyacrylates), methacrylate polymers (e.g., poly(meth)acrylates), polyvinyl alcohol, polyethylene glycol, polyvinylpyrrolidone, carbohydrates (e.g., dextrin, maltodextrin, starch), or combinations thereof.

[0126] The polymeric binder may include a binder selected from polyacrylates, poly(meth)acrylates and / or polyethylene glycols.

[0127] The binder may include phosphoric acid, colloidal silica, or a combination thereof.

[0128] The binder composition may further comprise a rheology modifier selected from the group including clays, organoclays, organothixotropes, acrylics, hydrophobically modified polyurethanes, polyether polyols. The binder composition may further comprise a suitable solvent, such as water or an alcohol, such as methanol, ethanol, propanol.

[0129] The binder composition may have a viscosity of at least 1 cP, such as at least 4 cP. The binder composition may have a viscosity of up to 10 cP, such as up to 7 cP. The binder composition may have a viscosity of 1 cP to 10 cP, such as 4 cP to 7 cP. The viscosity of the binder composition may be measured according to any suitable method known to those skilled in the art. For example, the viscosity of the binder composition may be measured using a capillary viscometer. Viscosity as used herein is understood to mean absolute viscosity.

[0130] The binder composition has a viscosity of at least 0.5 gcm -3 , e.g. at least 0.9 gcm -3 The binder may have a density of 2 gcm -3 Up to, for example, 1.2 gcm -3 The binder composition may have a density of up to 0.5 gcm -3 ~2gcm -3 , e.g. 0.9gcm -3 ~1.2gcm -3 The density may be

[0131] The binder composition may have a surface tension of at least 10 dynes / cm, such as at least 20 dynes / cm. The binder composition may have a surface tension of up to 80 dynes / cm, such as up to 50 dynes / cm. The binder composition may have a surface tension of 10 dynes / cm to 80 dynes / cm, such as 20 dynes / cm to 50 dynes / cm. The surface tension of the binder composition may be measured according to any suitable method known to the skilled artisan. For example, the surface tension of the binder composition may be measured using a surface tensiometer.

[0132] The binder composition may further comprise additive particles. The binder composition may further comprise additive particles selected from ceramic particles, metal particles, polymer particles, mixed metal particles, metal oxide particles and / or non-metal oxide particles. The binder composition may further comprise additive particles selected from ceramic particles, metal oxide particles and / or non-metal particles, such as ceramic particles and / or metal oxide particles. The binder composition may further comprise ceramic particles.

[0133] The additive particles may be ceramic additive particles. The ceramic additive particles may be formed from a ceramic selected from one or more of alumina, aluminum nitride, aluminum oxide, barium titanate, β-tricalcium phosphate, biological ceramic, bismuth, boron carbide, carbide, hydroxyapatite, iron oxide, magnesium silicate, nitride, oxide, aluminum silicon, silica, silicon carbide, silicon dioxide, silicon nitride, titanate, titanium dioxide, yttrium carbonate, YSZ (yttria stabilized zirconia), zinc oxide, zirconate, zirconia and zirconium, or mixtures thereof.

[0134] The additive particles may have an average particle size of 0.1 nm to 100 μm. The additive particles may have a particle size distribution with a D50 particle size of 0.1 nm to 100 μm.

[0135] The additive particles may be microparticles and / or nanoparticles.

[0136] The additive microparticles may have an average particle size of 0.1 μm to 100 μm, such as 0.1 μm to 20 μm, or 0.1 μm to 5 μm. The additive microparticles may have a particle size distribution with a D50 particle size of 0.1 μm to 100 μm, such as 0.1 μm to 20 μm, or 0.1 μm to 5 μm. The additive microparticles may have a particle size distribution with a D10 particle size of at least 0.1 μm, and / or a D90 particle size of up to 100 μm, such as up to 20 μm, or up to 5 μm.

[0137] The additive nanoparticles may have an average particle size of 0.1 nm to 100 nm, e.g., 1 nm to 50 nm, or 2 nm to 10 nm. The additive nanoparticles may have a particle size distribution in which the D50 particle size is 0.1 nm to 100 nm, e.g., 1 nm to 50 nm, or 2 nm to 10 nm. The additive nanoparticles may have a particle size distribution in which the D10 particle size is at least 0.1 nm, and / or the D90 particle size is up to 100 nm, e.g., up to 50 nm, or up to 10 nm.

[0138] The binder composition may comprise a mixture of additive microparticles and additive nanoparticles. The binder composition may comprise a mixture of additive microparticles and additive nanoparticles, where the volume ratio of microparticles to nanoparticles may be at least 1:20, such as at least 1:15, such as at least 1:10, such as at least 1:5, such as at least 1:2. The volume ratio of microparticles to nanoparticles may be up to 20:1, such as up to 15:1, such as up to 10:1, such as up to 5:1, such as up to 2:1.

[0139] The volume ratio of microparticles to nanoparticles may be 20:1 to 1:20, such as 15:1 to 1:15, such as 10:1 to 1:10, such as 5:1 to 1:5, such as 1:2 to 2:1. The volume ratio of microparticles to nanoparticles may be 1:1 to 20:1, such as 1:1 to 10:1, such as 5:1 to 10:1, or such as 2:1 to 10:1.

[0140] The particle size and particle size distribution of the additive particles, suitably additive microparticles and / or additive nanoparticles, may be measured by transmission electron microscopy (TEM) for the particle size range of 0.1 nm to 5 μm. Dynamic light scattering techniques (DLS) may be used to measure particle sizes from greater than 5 μm to 20 μm.

[0141] The additive particles of the binder composition may be incorporated into the 3D printed body and may remain in the ceramic film even after any post-processing of the 3D printed body is performed. Thus, the additive particles of the binder composition may be incorporated into the ceramic film.

[0142] The nanoparticles and / or microparticles may be formed in situ from nanoparticle and / or microparticle precursors during an additive manufacturing process. The nanoparticles and / or microparticles may be formed in situ from nanoparticle and / or microparticle precursors during a post-processing step of a 3D printed body.

[0143] It is understood that the term "in situ" as used herein relates to the formation of nanoparticles and / or microparticles during an additive manufacturing process and / or during post-processing steps of a 3D printed body. The nanoparticles and / or microparticles may be formed in situ from one or more precursor compounds.

[0144] It is understood that the term "formed" as used herein with respect to in situ formed nanoparticles and / or microparticles relates to any suitable chemical or physical change that transforms the nanoparticle and / or microparticle precursor into the final form of the nanoparticle and / or microparticle. The term "formed in situ" may relate to changing the nanoparticle and / or microparticle precursor from a first form to a second form during an additive manufacturing process and / or during post-processing steps of the 3D printed body. The change may include the formation and / or scission of covalent and / or ionic bonds. The change may include partial loss of some of the precursors of the nanoparticles and / or microparticles.

[0145] The nanoparticle and / or microparticle precursor may comprise any suitable reagent or mixture of reagents capable of forming nanoparticles and / or microparticles during an additive manufacturing process and / or during post-processing steps of a 3D printed body.

[0146] The nanoparticles and / or microparticles may be formed by heating the nanoparticle and / or microparticle precursor. The nanoparticles and / or microparticles may be formed by heating the nanoparticle and / or microparticle precursor to at least 100° C., such as at least 300° C., for example at least 500° C. The nanoparticles and / or microparticles may be formed by heating the nanoparticle and / or microparticle precursor to up to 1500° C., such as up to 1250° C., for example up to 800° C.

[0147] The nanoparticles and / or microparticles may be formed by heating the nanoparticle and / or microparticle precursor to a temperature of 100-1500°C, such as 300-1250°C, for example 500-800°C.

[0148] It will be apparent that the nanoparticle and / or microparticle precursors may themselves be of nanoparticle and / or microparticle size. The nanoparticle and / or microparticle precursors may reduce in size upon formation of the nanoparticles and / or microparticles in situ, thereby aiding in providing a controlled pore size in the membrane.

[0149] The nanoparticles and / or microparticles may be formed in situ via partially sacrificial nanoparticle and / or microparticle precursors, which may be partially sacrificial nanoparticles and / or microparticles.

[0150] The partially sacrificial nanoparticle and / or microparticle precursor may include a sacrificial component and a non-sacrificial component. The sacrificial component may be removed during the additive manufacturing printing process to form a ceramic membrane body and / or in a post-processing step of the 3D printed body. The non-sacrificial component is retained within the ceramic membrane. The non-sacrificial component may form nanoparticles and / or microparticles within the pores of the ceramic membrane. The sacrificial component may be removed by any suitable method known to those skilled in the art. For example, the sacrificial component may be removed by dissolution or decomposition. The sacrificial component may be removed by pyrolysis.

[0151] The partially sacrificial nanoparticle and / or microparticle precursor comprises a sacrificial component that may be partially sacrificed, typically partially sacrificed in situ, during an additive manufacturing process and / or during post-processing steps of the 3D printed body. The partially sacrificial nanoparticle and / or microparticle may be at least partially retained in the final ceramic film. In contrast, the sacrificial compound may be substantially completely removed in a post-processing step.

[0152] Advantageously, removal of the sacrificial components of the partially sacrificial nanoparticles and / or microparticles may result in the formation of controllable pore sizes and pore size distributions among the in situ generated nanoparticles and / or microparticles.

[0153] The nanoparticles and / or microparticles may comprise metal-silica nanoparticles and / or microparticles; metal oxide nanoparticles and / or microparticles; mixed metal oxide nanoparticles and / or microparticles; non-metal oxide nanoparticles and / or microparticles; and / or metal nanoparticles and / or microparticles. The nanoparticles and / or microparticles may comprise metal oxide nanoparticles and / or microparticles; silicon oxide nanoparticles and / or microparticles and / or metal-silicon oxide nanoparticles and / or microparticles. The nanoparticles and / or microparticles may comprise metal oxide nanoparticles and / or microparticles.

[0154] The metal-silica nanoparticles and / or microparticles may include nickel-silica, silver-silica, platinum-silica, and / or iron-silica nanoparticles and / or microparticles.

[0155] The metal-silica nanoparticles and / or microparticles may be obtainable from an in situ reaction between a polysilazane and a metal complex.

[0156] The metal complex may comprise a metal salt. The metal complex may comprise a metal acetate, metal chloride, metal oxide, metal hydroxide, metal isopropoxide, and / or metal cyclopentadiene. The metal of the metal complex may be selected from nickel, zinc, manganese, cobalt, platinum, iron, nickel, magnesium, chromium, and / or titanium.

[0157] The metal complexes may be selected from nickel acetate, zinc acetate, manganese acetate, cobalt acetate, platinum chloride, iron cyclopentadiene, nickel cyclopentadiene, magnesium oxide, chromium oxide, chromium hydroxide, and / or titanium isopropoxide.

[0158] The metal-silica nanoparticles and / or microparticles may be obtainable from an in situ reaction between a polysilazane and a metal complex at a temperature of at least 100°C, such as at least 200°C, for example at least 300°C, such as at least 400°C, for example at least 500°C, such as at least 600°C, for example about 700°C.

[0159] The metal oxide nanoparticles and / or microparticles may include aluminum oxide, magnesium oxide, titanium dioxide, magnesium oxide, copper oxide, and / or iron oxide nanoparticles and / or microparticles.

[0160] Metal oxide nanoparticles and / or microparticles may be obtained from the hydrolysis and condensation reaction of metal alkoxides, such as metal isopropoxides. Aluminum oxide nanoparticles and / or microparticles may be obtained from the hydrolysis and condensation reaction of aluminum alkoxides. The aluminum alkoxide may be selected from aluminum isopropoxide.

[0161] The aluminum oxide nanoparticles and / or microparticles may be obtainable from in situ reaction of alumoxane oxide nanoparticles and / or microparticles, such as carboxylate-alumoxane nanoparticles and / or microparticles. Thus, the alumoxane oxide nanoparticles and / or microparticles may be partially sacrificial nanoparticles and / or microparticles.

[0162] Alumoxane nanoparticles and / or microparticles may be obtainable from a reaction between boehmite and a carboxylic acid-containing compound.

[0163] The carboxylic acid-containing compound may comprise an optionally functionalized aliphatic group. The optionally functionalized aliphatic group may comprise at least 1 carbon atom in the aliphatic chain, such as at least 5 carbon atoms, such as at least 10 carbon atoms, such as at least 20 carbon atoms. The optionally functionalized aliphatic group may comprise 1 to 50 carbon atoms in the aliphatic chain, such as 2 to 30 carbon atoms, such as 3 to 10 carbon atoms.

[0164] The titanium dioxide nanoparticles and / or microparticles may be obtainable from the thermal decomposition of titanium alkoxides.The titanium dioxide nanoparticles and / or microparticles may be obtainable by hydrolysis and condensation of titanium alkoxides.

[0165] The titanium alkoxide may be selected from titanium isopropoxide.

[0166] Magnesium oxide nanoparticles and / or microparticles may be obtainable from magnesium nitrate under basic conditions.

[0167] Copper oxide nanoparticles and / or microparticles may be obtainable from the acidic decomposition of copper acetate.

[0168] Iron oxide nanoparticles and / or iron oxide microparticles may be obtainable from the hydrothermal oxidation of mixed iron(II) hydroxides and iron(III) hydroxides. Iron oxide nanoparticles and / or iron oxide microparticles may be obtainable from the thermal decomposition of iron complexes such as iron carbonyl or iron acetylacetonate.

[0169] The nanoparticles and / or microparticles may include mixed metal oxide nanoparticles and / or microparticles.

[0170] The mixed metal oxide nanoparticles and / or microparticles may be obtainable from a reaction between a transition metal salt, a rare earth metal salt and an organic acid. The mixed metal oxide nanoparticles and / or microparticles may comprise perovskite nanoparticles and / or microparticles. The mixed metal oxide nanoparticles and / or microparticles may be obtainable from a reaction between a transition metal salt, a rare earth metal salt and an organic acid carried out at at least 150° C., such as at least 350° C., such as at least 500° C., such as at least 750° C., such as at least 1000° C., or such as at least 1250° C. The transition metal salt and / or rare earth metal salt may comprise a metal nitrate and / or hydrate.

[0171] The nanoparticles and / or microparticles may include non-metal oxide nanoparticles and / or microparticles. The non-metal oxide nanoparticles and / or microparticles may include silica nanoparticles and / or microparticles. The silica nanoparticles and / or microparticles may be obtained from any suitable silica nanoparticle and / or microparticle precursor known to those skilled in the art. The silica nanoparticles and / or microparticles may be obtained by hydrolysis and condensation of silica alkoxides.

[0172] Suitable silica nanoparticle and / or microparticle precursors may include organosilicon compounds. Organosilicon compounds may include organosilanes such as vinyltriethoxysilane, 1,2-dimethoxy-1,1,2,2-tetramethyldisilane, and / or trimethoxyphenylsilane. Silica nanoparticle and / or microparticle precursors may include methoxysilane, ethoxysilane, silicon hydride, and / or silicon tetraacetate.

[0173] The nanoparticles and / or microparticles may comprise metal nanoparticles and / or microparticles. Suitable metal nanoparticle and / or microparticle precursors may include metal acetate complexes, metal acetylacetonate complexes, and / or metal cyclopentadienyl complexes.

[0174] The metal nanoparticles and / or microparticles may include silver nanoparticles and / or microparticles. Suitable silver nanoparticle and / or microparticle precursors may include a silver salt and a reducing agent, such as silver nitrate and sodium borohydride.

[0175] The film may include pores, and the nanoparticles and / or microparticles, or residues thereof, are disposed within the pores of the film. The film may include nanoparticles, or residues thereof, and the nanoparticles, or residues thereof, are disposed within the pores of the film. The film may include nanoparticles and / or microparticles formed in situ during an additive manufacturing process and / or post-processing step, and the nanoparticles and / or microparticles formed in situ, or residues thereof, are disposed within the pores of the film.

[0176] The presence of nanoparticles and / or microparticles in the pores of the ceramic member may provide smaller interparticle pore sizes than those produced in the absence of such nanoparticles and / or microparticles. When nanoparticles and / or microparticles are present, the porous ceramic material may include a higher number of interparticle pore sizes. When nanoparticles and / or microparticles are absent, the ceramic material may include a higher number of intermicroparticle pore sizes.

[0177] The membrane may include a coating, which may be operable to provide a separating effect, such that the coating may be operable to selectively promote the passage of some of the materials to be separated while reducing the passage of other materials.

[0178] The coating may include a hydrophilic agent and / or a superhydrophilic agent. The coating may include a first coating layer including a hydrophilic agent and a second coating layer including a superhydrophilic agent. The second coating layer may be disposed over at least a portion of the first coating layer.

[0179] A coating including a superhydrophilic agent may be disposed on the surface of the membrane that faces the feed stream.

[0180] The coating may be at least partially crosslinked and may include a superhydrophilic agent.

[0181] The coating may be formed from a coating composition, for example, that includes a hydrophilic agent and / or a superhydrophilic agent, and / or that is at least partially crosslinked, and a coating that includes a superhydrophilic agent may be formed from a coating composition that includes a hydrophilic agent or a precursor thereof (if present), and / or a superhydrophilic agent or a precursor thereof.

[0182] The surface of the membrane operable to receive the coating may be hydrophilic: the contact angle of water on the substrate surface may be 65° or less, such as 60° or less, preferably 55° or less.

[0183] The membrane may be pretreated. The membrane may be treated before the addition of the coating formulation. For example, the surface of the membrane may be subjected to hydrophilization to form a hydrophilic surface. This substrate treatment may include the addition of functional groups, suitably grafting and / or the addition of hydrophilic additives. The added functional groups may be selected from one or more of hydroxyl, ketone, aldehyde, carboxylic acid and amine groups, preferably hydroxyl or carboxylic acid groups.

[0184] The grafting of functional groups may be achieved by plasma treatment, corona discharge, redox reaction, radiation, UV ozone treatment, and / or chemical treatment. An example of plasma treatment is the use of oxygen plasma on the substrate for 30 seconds.

[0185] The functional groups of the membrane may be operable to interact with the functional groups of adjacent coating layers, for example, by physical and / or chemical bonds. For example, the grafted hydroxyl groups introduced by plasma treatment may be operable to react with carboxylated hydrophilic cellulosic materials in the coating layers via esterification, or with siloxane components in the intermediate layer.

[0186] Additionally or alternatively, the surface treatment may be achieved by incorporating a hydrophilic material into the membrane. Thus, the membrane may comprise a hydrophilic material.

[0187] Hydrophilic materials that may be incorporated into the membrane may include cellulose acetate, quaternized polyethersulfone, polylactic acid, polyethyleneimine, polyetherimide, polyvinylpyrrolidone, and / or poly(vinyl alcohol).

[0188] The hydrophilic material may be incorporated into the powder and / or binder so as to be incorporated into the 3D printed form of the membrane.

[0189] The membrane may comprise 1% or more by weight of the hydrophilic material, for example 5% or more by weight, or 7% or more by weight of the membrane. The membrane may comprise 50% or less by weight of the hydrophilic material, for example 35% or less by weight, or 25% or more by weight of the substrate. The membrane may comprise 1-50% by weight of the hydrophilic material, for example 5-35% by weight, or 7-25% by weight of the substrate.

[0190] Advantageously, the surface treatment may provide improved adhesion and uniformity of subsequent coating layers applied onto the membrane. The presence of said hydrophilicity and / or functionality on the membrane may provide a coating layer with more robust mechanical integrity, more uniform structure and improved continuity. The hydrophilicity and / or functionality may also provide improved longevity and / or stability. Surface treatments may also improve properties such as increased permeability.

[0191] The hydrophilic agent may be a material that has a surface tension lower than the surface energy of the substrate.

[0192] The hydrophilic agent, and / or a coating layer comprising the hydrophilic agent, may have a contact angle of 65° or less, such as 60° or less, or 55° or less, such as 50° or less.

[0193] The hydrophilic agent and / or a coating layer comprising a hydrophilic agent preferably has a higher contact angle than the superhydrophilic agent or a coating layer comprising a superhydrophilic agent.

[0194] The hydrophilic agent or precursor thereof may comprise a (co)polymer or oligomer, such as a polyelectrolyte, polydopamine, and / or polyethyleneimine, or a precursor thereof.

[0195] The hydrophilic agent (co)polymer may be branched.

[0196] The hydrophilic agent (co)polymer may have a weight average molecular weight (Mw) of at least 5,000 Da, such as at least 10,000 Da or at least 15,000 Da. The hydrophilic agent (co)polymer may have a weight average molecular weight (Mw) of up to 50,000 Da, such as up to 40,000 Da or up to 30,000 Da. The hydrophilic agent (co)polymer may have a weight average molecular weight (Mw) of 5,000 to 50,000 Da, such as 10,000 to 40,000 Da or 15,000 to 30,000 Da.

[0197] The hydrophilic agent (co)polymer may be formed from vinylpyrrolidone, vinyl alcohol, allylamine, ethyleneimine, allylammonium chloride, vinylamine, lysine, chitosan, silanes and / or derivatives thereof; acrylics, such as water-soluble acrylics; acrylamides (e.g., copolymers containing 2-acrylamido-2-methylpropanesulfonic acid-AMPS); and / or hydroxyalkyl methacrylates, such as hydroxyethyl methacrylate (e.g., polyHEMA), and copolymers thereof, such as copolymers with acrylic acid, methacrylic acid and / or 2-acrylamido-2-methylpropanesulfonic acid.

[0198] The hydrophilic polymer may be a copolymer formed from acrylamide and acrylic acid monomers and polyallylammonium chloride.

[0199] The hydrophilic agent may include two-dimensional and / or nanoparticulate materials.

[0200] The hydrophilic agent may include graphene based materials, metal organic framework materials, silicene, germanene, stanene, boron nitride, preferably h-boron nitride, carbon nitride, organometallic nanosheets, molybdenum disulfide, tungsten disulfide, polymer / graphene aerogels, and / or positively charged polymers.

[0201] The graphene-based materials may include graphene oxide, reduced graphene oxide, hydrated graphene, amino-based graphene, alkylamine-functionalized graphene oxide, ammonia-functionalized graphene oxide, amine-functionalized reduced graphene oxide, octadecylamine-functionalized reduced graphene oxide, and / or polymeric graphene aerogel, preferably graphene oxide.

[0202] The hydrophilic agent may have an average platelet size of from 1 nm to 100,000 nm, for example from 10 nm to 50,000 nm, or from 100 nm to 15,000 nm, preferably from 500 nm to 14,000 nm.

[0203] The hydrophilic agent may have a platelet size distribution D50 of 1 nm to 15,000 nm, preferably 100 nm to 14,000 nm. The graphene-based material may have a platelet size distribution D90 of 5 nm to 15,000 nm, preferably 100 nm to 14,000 nm.

[0204] The hydrophilic agent may have an oxygen atom content of from 1% to 70%, for example from 5% to 60%, or from 10% to 50%, preferably from 15% to 55%.

[0205] Suitably, the hydrophilic agent, preferably a graphene-based material such as graphene oxide, comprises hydroxyl, carboxyl and / or epoxide groups. The oxygen content of the hydrophilic agent, preferably having functional groups of hydroxyl and / or carboxyl groups, may be up to 60% oxygen atomic %, for example up to 50% or up to 45% oxygen atomic %. Suitably, the oxygen content is 20-25% or 25-45%. Advantageously, when the oxygen content is 25-45%, a surfactant may not be required to maintain the stability of the coating composition. Preferably, the oxygen content is 25-40 oxygen atomic %. Such a range may provide improved stability of the coating composition despite the absence of other stabilizing components such as surfactants and provide enhanced interaction with the primer layer. The oxygen content may be analyzed by X-ray photoelectron spectroscopy (XPS), K-Alpha grade, from ThermoFisher Scientific.

[0206] The oxygen content of the hydrophilic agent may be up to 50% oxygen atomic percent.

[0207] The oxygen content of the hydrophilic agent may be from 25 to 45%.

[0208] The size distribution of the hydrophilic agent may be such that at least 30% by weight of the material has a diameter of 1 nm to 5,000 nm, for example 1 to 750 nm, 100 to 500 nm, 100 to 400 nm, 500 to 1000 nm, 1000 to 3000 nm, 1000 to 5000 nm, 1500 to 2500 nm, or 500 to 1500 nm, preferably 100 to 3000 nm, more preferably at least 40% by weight, 50% by weight, 60% by weight, 70% by weight, most preferably at least 80% by weight or at least 90% by weight or 95% by weight or 98% by weight or 99% by weight has a diameter in the above range. The size and size distribution of the hydrophilic agent may be measured using transmission electron microscopy (TEM, JEM-2100F, JEOL, Japan).

[0209] The hydrophilic agent may be in the form of a monolayer or multilayer particle, preferably a monolayer. The hydrophilic agent particles may be formed of a monolayer, two layers or a few layers of hydrophilic agent, a few layers may be defined as 3-20 layers. Suitably, the hydrophilic agent may comprise 1-15 layers, for example 2-10 layers or 5-15 layers. Suitably, at least 30% by weight of the hydrophilic agent comprises 1-15 layers, for example 1-10 layers or 5-15 layers, more preferably at least 40%, 50%, 60%, 70%, most preferably at least 80% by weight or at least 90% by weight or 95% by weight or 98% by weight or 99% by weight comprises the above number of layers. The number of layers in the hydrophilic agent may be measured using atomic force microscopy (AFM or transmission electron microscopy (TEM)) (TT-AFM, AFM workshop Co., California, USA).

[0210] Preferably, the d spacing between adjacent lattice planes in the hydrophilic agent or mixture thereof is 0.34 nm to 5000 nm, for example, 0.34 nm to 1000 nm, or 0.4 to 500 nm, or 0.4 to 250 nm, for example, 0.4 to 200 nm, or 0.4 to 150 nm, or 0.4 to 100 nm, or 0.4 to 50 nm, or 0.4 to 25 nm, or 0.4 to 10 nm, or 0.4 to 8 nm, for example, 0.4 to 7 nm, 0.45 to 6 nm, 0.50 to 5 nm, or 0.55 to 4 nm, or 0.6 to 3 nm, for example, 0.6 to 2.5 nm, 0.6 to 1 nm, 0.6 to 2 nm, or 0.6 to 1.5 nm.

[0211] The water contact angle of the superhydrophilic agent, coating layer or coating composition, suitably the second coating layer comprising the superhydrophilic agent, may be 25° or less, such as 20° or less, for example 15° or less, preferably 10° or less. As used herein, water contact angle was measured according to ASTM D7334-08.

[0212] The water contact angle of the superhydrophilic agent or coating layer, suitably the water contact angle of the second coating layer comprising the superhydrophilic agent, may be less than or equal to 20°.

[0213] The superhydrophilic agent may comprise a (co)polymer or oligomer, such as a polyelectrolyte or a precursor thereof.

[0214] The superhydrophilic (co)polymer and / or the hydrophilic (co)polymer may comprise a hydrogel or be operable to form a hydrogel upon contact with water.

[0215] Superhydrophilic (co)polymers include vinyl monomers such as styrene sulfonates, vinyl ethers (such as methyl vinyl ether), N-vinyl-2-pyrrolidone (NVP), vinyl acetate (VAc); silane-based monomers and / or their derivatives; acrylic monomers such as (hetero)aliphatic (alk) acrylates, acrylic acid and its salts, bisphenol acrylics, fluorinated acrylates, methacrylates, multifunctional acrylates, hydroxyethoxyethyl methacrylate (HEEMA), hydroxydiethoxyethyl methacrylate (HYD), hydroxydiethoxyethyl methacrylate (HYD). (HDEEMA), methoxyethyl methacrylate (MEMA), methoxyethoxyethyl methacrylate (MEEMA), methoxydiethoxyethyl methacrylate (MDEEMA), ethylene glycol dimethacrylate (EGDMA), acrylic acid (AA), PEG acrylate (PEGA), PEG methacrylate (PEGMA), PEG diacrylate (PEGDA), PEG dimethacrylate (PEGDMA), bis(trimethylsilyloxy)methylsilylpropyl glycerol methacrylate (SiMA), methacryloyl hydroxyethyl phosphorylcholine (MPC), 6-acetylthiohexyl methacrylate, acrylic anhydride, [2-(acryloyloxy)ethyl]trimethylammonium chloride, 2-(4-benzoyl-3-hydroxyphenoxy)ethyl acrylate, benzyl acrylate, or their trimethacrylate, dimethacrylate triblock derivatives; thiol-functionalized acrylate monomers, such as thiol-functionalized (meth)acrylates; acryloyl chloride; acrylonitrile; maleimide; acrylamide-based monomers, such as acrylamide, methacrylamide; N,N-dimethylacrylamide (DMA), 2-acrylamido-2-methylpropanesulfonic acid, N-isopropyl AAm (NIPAAm), N-(2-hydroxypropyl) methacrylamide (HPMA), 4-acryloylmorpholine; carbohydrate monomers; polyacids and / or polyols such as maleic acid (e.g., maleic acid with vinyl ethers (e.g., Gantrez partially neutralized with sodium)), ethylene glycol (EG); gelatin methacryloyl;and / or may be formed from monomers including methacrylated hyaluronic acid, optionally with a crosslinker, such as epichlorohydrin (ECH), N,N'-methylene-bis-acrylamide (BIS) and / or divinylsulfone (DVS);

[0216] The superhydrophilic (co)polymer may have a molecular weight (Mw) of 2,000 g / mol or more, such as 4,000 g / mol or more, or 6,000 g / mol or more, such as up to 30,000 g / mol or less, such as up to 20,000 g / mol or less, or up to 15,000 g / mol or less, such as from 2,000 to 30,000 g / mol, such as from 4,000 to 20,000 g / mol, or from 6,000 to 15,000 g / mol.

[0217] The superhydrophilic (co)polymer may have a molecular weight (Mw) of 6,000 g / mol or greater.

[0218] The superhydrophilic (co)polymer may have a molecular weight (Mw) of 2,000 to 30,000 g / mol.

[0219] The coating or coating composition may comprise a film former, such as a linear and / or hydrophilic polymer (such as PVP). The film former may be selected from polysaccharides or derivatives thereof, such as cellulose or derivatives thereof, such as methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, cellulose acetate phthalate, hydroxypropylmethylcellulose phthalate, carboxymethylethylcellulose, hydroxypropylmethylcellulose acetate succinate, ethylcellulose, sodium alginate; acrylic (co)polymers; vinyl (co)polymers, such as polyvinylpyrrolidone; polyvinyl alcohol, polyvinyl acetate phthalate; polyethylene glycol, polyethyleneimine (PEI); and / or poly(ethylene) oxide. Preferably, the film former comprises a water-soluble film former, such as hydroxypropylmethylcellulose acetate succinate.

[0220] The amount of film former in the coating composition may be 10 wt% or less, such as 5 wt% or less, for example 4 wt% or less, 3.5 wt% or less, 3 wt% or less, 2.5 wt% or less, preferably 2 wt% or less, based on the dry weight of the coating composition.

[0221] The hydrophilic agent, superhydrophilic agent, or precursor thereof, coating layer and / or film former, if present, may be at least partially crosslinked or may be operable to be at least partially crosslinked. The hydrophilic agent, superhydrophilic agent, or precursor thereof, film former and / or coating layer may be at least partially crosslinked by using an additive crosslinking agent. Thus, a coating composition comprising a hydrophilic agent, superhydrophilic agent and / or film former may further comprise an additive crosslinking agent. The hydrophilic agent, superhydrophilic agent, or precursor thereof, coating layer and / or film former may be at least partially self-crosslinked or may be operable to be pre-self-crosslinked.

[0222] The hydrophilic (co)polymer, superhydrophilic (co)polymer, or precursors thereof, and / or film former (co)polymer, if present, may suitably be formed from crosslinker or residues thereof in an amount of 0.5% or more, or 0.8% or more, or 1% or more, such as up to 15% or less, up to 10% or less, or up to 5% by weight of the total monomers of the (co)polymer, for example 0.5-15% or 0.8-10% or 1-5% by weight of the total monomers of the (co)polymer.

[0223] The coating composition may comprise a crosslinker in an amount of 0.5% or more, such as 0.8% or more or 1% by weight of the dry weight of the composition, for example up to 15% by weight, such as up to 10% or less or up to 5% by weight of the dry weight of the composition, for example from 0.5 to 15%, such as from 0.8 to 10% or 1 to 5% by weight of the dry weight of the composition.

[0224] The superhydrophilic (co)polymer may be formed from a crosslinker in an amount of 0.5% or more by weight of the total monomers of the (co)polymer.

[0225] The hydrophilic (co)polymer, superhydrophilic (co)polymer, or precursor thereof, and / or film former (co)polymer may be formed from a crosslinker or residue thereof, when present, suitably in an amount of 0.5 to 15% by weight of the total monomers of the (co)polymer.

[0226] The crosslinking agent may be a polyfunctional acrylic or vinyl monomer, a divalent metal ion, a polyfunctional carbodiimide, a polyfunctional aziridine, a silane; a polyfunctional epoxide and / or a polyfunctional isocyanate, or a residue thereof.

[0227] Crosslinkers may include tetramethylethylenediamine, methylenebisacrylamide, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, triethylene glycol dimethacrylate, N-isopropylacrylamide; N,N-diethylacylamide, epichlorohydrin (ECH), N,N'-methylene-bis-acrylamide (BIS), divinylsulfone (DVS), citric acid, dicysteine ​​peptides, dithiothreitol (DTT), glutaraldehyde; enzymatic crosslinkers such as transglutaminase, and combinations of horseradish peroxidase (HRP) and hydrogen peroxide, or residues thereof.

[0228] The hydrophilic agent, superhydrophilic agent, or precursor thereof, and / or film former, when present, may include a functional group, or residue thereof, operable to be crosslinked. For example, the hydrophilic agent, superhydrophilic agent, or precursor thereof, and / or film former, when present, may include an acid functional group, such as a carboxylic acid functional group, or residue thereof. In the coating layer, the crosslink density may be at least 2 mol %, such as at least 5 mol % or at least 10 mol % of the crosslinkable functional groups.

[0229] The crosslink density may be at least 2 mole percent of the crosslinkable functional groups.

[0230] As used herein, crosslink density was measured in the following manner: the polymer was swollen in the solvent until equilibrium. The swollen gel was then isolated and weighed. The weight of the swelling solvent and polymer was measured after removing the solvent by vacuum drying. The following formula was then applied: Crosslink density, network chains per gram = [ln(1-Vp)+(Vp)+X(Vp)^2] / {Dp(Vo)[(Vr)^(1 / 3)-(Vp) / 2]} During the ceremony, Vp = volume fraction of polymer in swollen polymer X = Huggins polymer-solvent interaction constant Dp = density of polymer (g / cm^3) Vo = molar volume of the solvent (cm^3 / mol) Do = density of the solvent (g / cm^3) Where: Vp=1 / (1+Q) where Q is the ratio of the weight of solvent (XDp) to the weight of polymer (XDo) in the swollen polymer.

[0231] The superhydrophilic agent may be a polyelectrolyte (co)polymer selected from (meth)acrylic acid (co)polymers and / or styrene sulfonic acid (co)polymers, at least a portion of the acid being in the form of a suitable salt.

[0232] The superhydrophilic agent may be a polyelectrolyte copolymer selected from sodium poly(styrene-alt-maleic acid), sodium chitosan-g-poly(acrylic acid) copolymer; 2-propenoic acid, 2-methyl, polymer with sodium; and / or 2-methyl-2((1-oxo-2-propen-1-yl)amino)-1-propanesulfonate.

[0233] Superhydrophilic agents include carboxymethylcellulose (CMC) and / or polyvinylpyrrolidone (PVP) hydrogels, for example crosslinked with tetra(ethylene glycol) dimethacrylate via free radical polymerization or the like, suitably with at least a portion of the acid in the form of a suitable salt such as sodium carboxymethylcellulose (CMC); N-isopropylacrylamide with poly(ethylene glycol)-co-polycaprolactone (PEG-co-PCL), crosslinked with N,N'-methylenebisacrylamide and / or sodium alginate, for example by using template copolymerization or UV light, or with N,N,N',N'-tetramethylethylenediamine and / or ammonium persulfate (APS) with UV light, for example alginic acid, alginic acid derivatives; 3-(methacryloyloxy)propyltris(trimethylsiloxy)silane, N,N-dimethylacrylamide, 3-(methacryloyloxy)propyltris(trimethylsiloxy)silane. 1-vinyl-2-pyrrolidinone, and / or 2-hydroxyethyl methacrylate (TRIS-DMA-NVP-HEMA copolymer hydrogel).

[0234] Hydrogels as used herein with respect to hydrophilic and superhydrophilic agents may refer to insoluble polymer networks characterized by the presence of physical and / or chemical crosslinks between polymer chains and the presence of water in suitably non-negligible amounts, e.g., at least 10% by weight of the total polymer composition. The hydrophilic and / or superhydrophilic agents may be in the form of a dehydrated hydrogel operable to form a hydrated hydrogel upon contact with water.

[0235] The superhydrophilic agent may include poly(styrenesulfonate salts) and / or polyacrylate salts.

[0236] The term "precursor" as used herein with respect to hydrophilic and superhydrophilic agents refers to a compound operable to form a hydrophilic or superhydrophilic agent using methods known to those skilled in the art. For example, the precursor may be an oligomer or a pre-crosslinked polymer that forms a hydrophilic or superhydrophilic agent after chemical or physical crosslinking, such as with UV light with a photoinitiator, heat treatment, or the like. For example, the precursor may include a mixture of poly(allylmonium chloride) and acrylamide and acrylic acid monomers with 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AIBA) as an initiator and N,N'-methylenebisacrylamide (MBAM) as a crosslinker. This mixture may be considered to be a hydrophilic agent precursor since it is operable to form a hydrophilic agent in a coating layer via template polymerization. Another example of a suitable precursor includes polyethylene glycol (PEG) mixed with triethylene glycol dimethacrylate (TEGDMA), which is operable to form a hydrophilic agent in a coating layer via UV light with a photoinitiator.

[0237] The coating composition may include a buffer operable to maintain the composition in a suitable pH range, such as tris(hydroxymethyl)aminomethane (Tris). The pH of the coating composition may be from 8 to 9, for example from 8 to 8.5.

[0238] The thickness of the coating, suitably the first coating layer, may be from 1 nm to 2000 nm.

[0239] The thickness of the coating layer containing the superhydrophilic agent may be up to 100 μm.

[0240] The coating may include an intermediate layer between the membrane and the first coating layer, and / or between the first coating layer and the second coating layer.

[0241] The intermediate layer may comprise an adhesion promoter selected from silanes or derivatives thereof, tannic acid, dopamine or derivatives thereof, and / or dopamine peptides; amines; diamines; methacrylates; epoxies; methyl, isobutyl, phenyl, octyl, or vinyl, chloroalkyls; vinylbenzylamino-based adhesion promoters; organometallics, such as organotitanates, organozirconates, organoaluminates; chlorinated or chlorine-free polyolefins; polyol-based adhesion promoters; and / or polyester-based adhesion promoters.

[0242] The adhesion promoter may comprise a silane-based adhesion promoter, such as acrylate and / or methacrylate functional silanes, aldehyde functional silanes, amino functional silanes; such as aminoalkoxysilanes, anhydride functional silanes, azide functional silanes, carboxylate phosphonate and / or sulfonate functional silanes, epoxy functional silanes, ester functional silanes, halogen functional silanes, hydroxyl functional silanes, isocyanate and / or masked isocyanate functional silanes, phosphine and / or phosphate functional silanes, sulfur functional silanes, vinyl and / or olefin functional silanes, multifunctional and / or polymeric silanes, UV active and / or fluorescent silanes, and / or chiral silanes, trihydrosilanes.

[0243] The adhesion promoter may include 3-aminopropyltrimethoxysilane.

[0244] The coated membrane is a. optionally preparing a substrate by treating the film described herein with physical rinsing, chemical treatment, radiation treatment, plasma treatment, and / or heat treatment; b. optionally, contacting the substrate with an intermediate layer coating composition to form an intermediate layer; c. contacting the substrate / membrane with a coating composition comprising a hydrophilic agent or a precursor thereof, and optionally further comprising a superhydrophilic agent or a precursor thereof, to form a coating layer; d. optionally, contacting the coating layer with an intermediate layer coating composition to form an intermediate layer; e. if a superhydrophilic agent was not contacted with the substrate in step (c), contacting the coated substrate with a coating composition comprising a superhydrophilic agent or a precursor thereof to form a further coating layer; It may be formed by:

[0245] The coated membrane is a. optionally preparing the substrate by physical washing off the film and treating with chemical, radiation, plasma, and / or thermal treatments; b. optionally, contacting the substrate with an intermediate layer coating composition to form an intermediate layer; c. optionally contacting the substrate with a coating composition comprising a hydrophilic agent or a precursor thereof to form a coating layer; d. optionally, contacting the coating layer with an intermediate layer coating composition to form an intermediate layer; e. optionally contacting the coated membrane with a coating composition comprising a superhydrophilic agent or a precursor thereof to form a coating layer; wherein the coating layer including the superhydrophilic agent is at least partially crosslinked.

[0246] The coating may comprise a lamellar structure comprising at least two layers of a two-dimensional material, the two-dimensional material comprising graphene or a derivative thereof. The coating may be formed from a coating composition comprising graphene or a derivative thereof.

[0247] The graphene or derivatives thereof may be selected from one or more of graphene oxide, reduced graphene oxide, hydrated graphene and amino-based graphene, alkylamine-functionalized graphene oxide, ammonia-functionalized graphene oxide, amine-functionalized reduced graphene oxide, octadecylamine-functionalized reduced graphene oxide, and / or polymeric graphene aerogel. Preferably, the graphene or derivatives thereof is graphene oxide. Graphene and its derivatives may be commercially obtained from Sigma-Aldrich.

[0248] Suitably, the graphene or its derivative, preferably graphene oxide, comprises hydroxyl groups, carboxyl groups and / or epoxide groups. The oxygen content of the graphene or its derivative, preferably graphene oxide, may be 0% to 60% oxygen atomic %, for example 0% to 50% or 0% to 45% oxygen atomic %. Suitably, the oxygen content is 20% to 25% or 25% to 45%. Advantageously, when the water content is 25% to 45%, no surfactant may be present in the composition. Preferably, the oxygen content is 30% to 40% oxygen atomic %. Such a range may provide improved stability despite the absence of other stabilizing components. Suitably, when the graphene or derivative is reduced graphene oxide, the oxygen content is 5% to 20% oxygen atomic %. The oxygen content may be analysed by X-ray photoelectron spectroscopy (XPS).

[0249] Graphene or its derivatives, preferably graphene oxide, may be optionally substituted with further functional groups. The optional functional groups may be grafted functional groups, preferably grafted via reaction with existing hydroxyl, carboxyl and epoxide groups of graphene or its derivatives. Functionalization includes covalent and non-covalent modification. Covalent modification methods can be sub-classified into nucleophilic substitution reactions, electrophilic substitution reactions, condensation reactions and addition reactions. Examples of optional functional groups are amine groups; aliphatic amine groups, e.g. long chain (e.g. C 18 ~C 50) aliphatic amine groups; porphyrin-functionalized secondary amine groups, and / or 3-amino-propyltriethoxysilane groups. The graphene or its derivatives may comprise amino groups, suitably grafted amino groups, preferably grafted to graphene oxide. Such functionalization may result in improved selective sieving of ferric acid.

[0250] The graphene or derivative thereof according to any of the embodiments of the present invention may be in the form of flakes having a size of 1 nm to 5000 nm, for example, 50 nm to 750 nm, 100 nm to 500 nm, or 100 nm to 400 nm. The graphene or derivative thereof according to any of the embodiments of the present invention may be in the form of flakes having a size of 100 nm to 3500 nm, for example, 200 nm to 3000 nm, 300 nm to 2500 nm, or 400 nm to 2000 nm, preferably 500 nm to 1500 nm. The graphene or derivative thereof according to any of the embodiments of the present invention may be in the form of flakes having a size of 500 nm to 4000 nm, 500 nm to 3500 nm, 500 nm to 3000 nm, 750 nm to 3000 nm, or 1000 nm to 3000 nm, for example, 1250 nm to 2750 nm, or preferably 1500 nm to 2500 nm. Suitably, the size distribution of the graphene flakes or derivatives thereof is such that at least 30 wt. % of the graphene flakes or derivatives thereof are in the range of 1 nm to 5000 nm, e.g. 1 nm to 750 nm, 100 nm to 500 nm, 100 nm to 400 nm; or 100 nm to 3500 nm, e.g. 200 nm to 3000 nm, 300 nm to 2500 nm or 400 nm to 2000 nm, preferably 500 nm to 1500 nm; or 500 nm to 4000 nm, 500 nm to 35 00nm, 500nm to 3000nm, 750nm to 3000nm, 1000nm to 3000nm, for example 1250nm to 2750nm or preferably 1500nm to 2500nm, more preferably at least 40wt%, 50wt%, 60wt%, 70wt%, most preferably at least 80wt% or at least 90wt% or 95wt% or 98wt% or 99wt% have a diameter in the above range. The size and size distribution of the graphene flakes or derivatives thereof may be measured using transmission electron microscopy (TEM, JEM-2100F, JEOL, Japan).

[0251] The graphene or its derivatives may be in the form of monolayer or multilayer particles, preferably monolayer. The graphene flakes or its derivatives may be formed of a monolayer, two layers or a small number of layers of graphene or its derivatives, a small number being defined as 3-20 layers. Suitably, the graphene flakes or its derivatives comprise 1-15 layers, such as 2-10 layers or 5-15 layers. Suitably, at least 30% by weight of the graphene flakes or its derivatives comprise 1-15 layers, such as 1-10 layers or 5-15 layers, more preferably at least 40%, 50%, 60%, 70%, most preferably at least 80% by weight or at least 90% by weight or 95% by weight or 98% by weight or 99% by weight of the graphene flakes comprise the above number of layers. The number of layers in graphene flakes or its derivatives may be measured using atomic force microscopy (AFM or transmission electron microscopy (TEM)) (TT-AFM, AFM workshop Co., California, USA).

[0252] Preferably, the d spacing between adjacent lattice planes in graphene or a derivative thereof is 0.34 nm to 1000 nm, for example, 0.34 nm to 500 nm, or 0.4 nm to 500 nm, or 0.4 nm to 250 nm, for example, 0.4 nm to 200 nm, or 0.4 nm to 150 nm, or 0.4 nm to 100 nm, or 0.4 nm to 50 nm, or 0.4 nm to 25 nm, or 0.4 nm to 10 nm, or 0.4 nm to 5 nm, for example, 0.45 nm to 4 nm, 0.5 nm to 3 nm, 0.55 nm to 2 nm, or 0.55 nm to 1.5 nm, or 0.6 nm to 1.2 nm, for example, 0.6 nm to 1.1 nm, 0.6 nm to 1 nm, 0.6 nm to 0.9 nm, or 0.6 nm to 0.8 nm.

[0253] The coating may comprise materials other than graphene or its derivatives, preferably two-dimensional materials, for example the other materials of the coating may be selected from one or more of silicene, germanene, stanene, boron nitride, preferably h-boron nitride, carbon nitride, organometallic nanosheets, molybdenum disulfide and tungsten disulfide, polymer / graphene aerogels.

[0254] The coating materials may be produced using any suitable method known to those skilled in the art. Two-dimensional silicene, germanene and stanene may be produced by surface-assisted epitaxial growth under ultra-high vacuum. Hexagonal two-dimensional h-boron nitride may be produced by several methods such as mechanical cutting, dissection (deconstruction) of boron nitride nanotubes, chemical functionalization and sonication, solid-state reaction and solvent exfoliation and sonication. Among these methods, chemical methods have been found to provide the highest yield. For example, h-boron nitride may be synthesized on a single crystal transition metal substrate using borazine as the boron source and the nitride source. Two-dimensional carbon nitride can be prepared by direct microwave heating of melamine and carbon fibers. Metal organic frameworks (MOFs) can be produced by in situ solvothermal synthesis by mixing the components at high temperatures such as 100-140°C followed by filtration. Two-dimensional molybdenum disulfide can be obtained by several methods such as mechanical exfoliation, liquid exfoliation and chemical exfoliation. Among these methods, chemical exfoliation has been found to provide high yields. One example is chemical exfoliation, which uses lithium to chemically exfoliate molybdenum disulfide using centrifugation and filtration. Two-dimensional tungsten disulfide can be prepared by a deposition-thermal annealing method: vacuum deposition (evaporation) of tungsten and subsequent thermal annealing with the addition of sulfur. Polymer / graphene aerogels can be produced by coupling with polyethylene glycol-grafted graphene oxide and subsequent freeze-drying.

[0255] A method of applying a coating composition to a film may include applying a coating composition comprising graphene or a derivative thereof to a film, the method may include contacting the film with the coating composition using gravity deposition, vacuum deposition, pressure deposition, printing such as inkjet printing, aerosol printing, 3D printing, offset lithography printing, gravure printing, flexographic printing techniques, pad printing, curtain coating, dip coating, spin coating, and other printing or coating techniques known to those skilled in the art.

[0256] Further details of the application method are disclosed in published PCT patent application WO2019106344, specifically in paragraphs

[47] -

[49] and

[61] -

[69] , inclusive. The entire contents of paragraphs

[47] -

[49] and

[61] -

[69] , inclusive, are hereby incorporated by reference in their entirety.

[0257] The coating composition may be a liquid composition comprising a liquid medium and graphene or a derivative thereof. The coating composition of the present invention may comprise a solvent, may be non-solvent or solvent-free, and may be a UV curable composition, an electron beam curable composition, or the like. When formulated as a liquid composition for use in the present invention, e.g., as a solution, dispersion, or suspension, a suitable carrier liquid or solvent may be aqueous or organic, with other components selected accordingly. For example, the liquid carrier may comprise water or an organic solvent, e.g., ethanol, terpineol, dimethylformamide, N-methyl-2-pyrrolidone, isopropyl alcohol, mineral oil, ethylene glycol, or mixtures thereof, optionally with other materials that enhance the performance and / or rheology of the composition, including any one or more of binders, drying additives, antioxidants, reducing agents, lubricants, plasticizers, waxes, chelating agents, surfactants, pigments, defoamers, and sensitizers.

[0258] Further details of the coating composition are disclosed in the published PCT patent application WO 2019 / 106344 pamphlet, specifically in paragraphs

[51] to

[60] (including the paragraphs at both ends). The entire content of paragraphs

[51] to

[60] (including the paragraphs at both ends) is hereby incorporated by reference in its entirety into this specification.

[0259] The coating may include a lamellar structure including at least two layers of a two-dimensional material, and the two-dimensional material includes a transition metal dichalcogenide. The coating may be formed from a coating composition including a transition metal dichalcogenide.

[0260] The transition metal dichalcogenide may be of formula (I) M a X b (I) wherein, M is a transition metal atom, such as Mo, W, Nb, Ni, X is a chalcogen atom, preferably S, Se or Te, 0 < a ≤ 1 and 0 < b ≤ 2.

[0261] The transition metal dichalcogenide is MoS2, MoSe2, WS2, WSe2, Mo a W 1-a S2, Mo a W 1-a Se2, MoS b Se 2-b 、WS b Se 2-b 、or Mo a W 1-a S b Se 2-b 、or one or more combinations thereof, wherein 0 < a ≤ 1 and 0 < b ≤ 2. Preferably, the transition metal dichalcogenide is selected from MoS2, WS2, MoSe2, WSe2, most preferably from MoS2 and WS2. Such transition metal dichalcogenides are commercially available from ACS Material.

[0262] The transition metal dichalcogenides may be in the form of flakes having an average size of 1 nm to 5000 nm, for example 50 to 750 nm, 75 nm to 500 nm, 100 nm to 400 nm, for example 130 nm to 300 nm, 150 nm to 290 nm, or 160 nm to 280 nm, suitably 170 nm to 270 nm, 180 nm to 260 nm or preferably 190 nm to 250 nm. Suitably, the size distribution of the transition metal dichalcogenide flakes is such that at least 30% by weight of the transition metal dichalcogenide flakes have a diameter of 1 nm to 5000 nm, for example 50 to 750 nm, 75 to 500 nm, 100 nm to 400 nm, for example 130 nm to 300 nm, 150 nm to 290 nm, or 160 nm to 280 nm, suitably 170 nm to 270 nm, 180 nm to 260 nm or preferably 190 nm to 250 nm, more preferably at least 40% by weight, 50% by weight, 60% by weight, 70% by weight, most preferably at least 80% by weight or at least 90% by weight or 95% by weight or 98% by weight or 99% by weight have a diameter in the above ranges. The size and size distribution of the transition metal dichalcogenide may be measured using a transmission electron microscope (TEM, JEM-2100F, JEOL, Japan).

[0263] For example, the lateral size of the 2D layers across the sample may be measured using transmission electron microscopy (TEM, JEM-2100F, JEOL, Japan), and the same size of nanosheets (M i ) number (N i ) may be measured. The average size may then be calculated according to Equation 1.

number

[0264] The transition metal dichalcogenide may be in the form of monolayer or multilayer particles or flakes, preferably monolayer particles or flakes. The transition metal dichalcogenide flakes may be formed of a monolayer, two layers or a few layers of transition metal dichalcogenide, a few layers being defined as 3 to 100 layers. Suitably, the transition metal dichalcogenide flakes comprise 1 to 100 layers, such as 2 to 75 layers or 5 to 50 layers or 10 to 25 layers. Suitably, at least 30% by weight of the transition metal dichalcogenide comprises 1 to 30 layers, such as 5 to 30 layers or 5 to 10 layers, more preferably at least 40%, 50%, 60%, 70%, most preferably at least 80% by weight or at least 90% by weight or 95% by weight or 98% by weight or 99% by weight comprises the above number of layers. The layer number of the transition metal dichalcogenide flakes may be measured using atomic force microscopy (AFM or transmission electron microscopy (TEM)) (TT-AFM, AFM workshop Co., CA, USA).

[0265] Preferably, the d spacing between adjacent lattice planes in the transition metal dichalcogenide or mixture thereof is 0.34 nm to 5000 nm, for example, 0.34 nm to 1000 nm, or 0.4 to 500 nm, or 0.4 to 250 nm, for example, 0.4 to 200 nm, or 0.4 to 150 nm, or 0.4 to 100 nm, or 0.4 to 50 nm, or 0.4 to 25 nm, or 0.4 to 10 nm, or 0.4 to 8 nm, for example, 0.4 to 7 nm, 0.45 to 6 nm, 0.50 to 5 nm, or 0.55 to 4 nm, or 0.6 to 3 nm, for example, 0.6 to 2.5 nm, 0.6 to 1 nm, 0.6 to 2 nm, or 0.6 to 1.5 nm.

[0266] The coating may comprise other materials than the transition metal dichalcogenide, preferably two-dimensional materials, for example the other materials of the coating may be selected from one or more of silicene, germanene, stanene, boron nitride, preferably h-boron nitride, carbon nitride, organometallic nanosheets, graphene, graphene oxide, reduced graphene oxide, functionalized graphene oxide and polymer / graphene aerogels.

[0267] Further details of the application method are disclosed in published PCT patent application WO 2019 / 122828, specifically at paragraphs

[73] -

[77] , inclusive, the entire contents of which are hereby incorporated by reference in their entirety.

[0268] Further details of the coating composition are disclosed in published PCT patent application WO 2019 / 122828, specifically in paragraphs

[46] -

[61] , inclusive, the entire contents of which are hereby incorporated by reference in their entirety.

[0269] The coating may include a metal organic framework (MOF). The coating may be formed from a coating composition that includes a MOF.

[0270] The metal organic framework material of any embodiment of the present invention may be one-dimensional, two-dimensional or three-dimensional. Preferably, the MOF is porous. The MOF may comprise a network of secondary building units (SBUs) or metal ion cores / metal subunit cluster core nodes and organic linkers (or ligands) connecting the SBUs or nodes.

[0271] The MOFs may be a continuous phase in the coating or may be in the form of flakes and / or particles. The MOFs synthesized in the presence of the first support moiety may be in the form of a continuous phase. The MOFs formed prior to contact with the first support moiety may be in the form of flakes and / or particles.

[0272] The subunits of the MOF, SBUs or nodes, can be one or more transition metal cations, such as Cr(III), Fe(II), Fe(III), Al(III), Co(II), Ru(III), Os(III), Hf(IV), Ni, Mn, V, Sc, Y(III), Cu(II), Cu(I), Zn(II), Zr(IV), Cd, Pb, Ba, Ag(I), Au, AuPd, Ni / Co, lanthanides, actinides, such as Lu, Tb( III), Dy(III), Ho(III), Er(III), Yb(III), preferably Cr(III), Fe(II), Fe(III), Al(III), Co(II), Ru(III), Os(III), Hf(IV), Ni, Mn, V, Sc, Y(III), Cu(II), Cu(I), Zn(II), Zr(IV), Cd, Pb, Ba, Ag(I), Ni / Co, lanthanides, actinides, e.g. Lu, Tb(III), Dy (III), Ho(III), Er(III), Yb(III), more preferably Cr(III), Fe(II), Fe(III), Al(III), Co(II), Hf(IV), Ni, Mn, V, Sc, Y(III), Cu(II), Cu(I), Zn(II), Zr(IV), Cd, Pb, Ag(I), Ni / Co, lanthanides, actinides, e.g. Lu, Tb(III), Dy(III), Ho(III), Er(III), Yb (III), more preferably Cr(III), Fe(II), Fe(III), Al(III), Co(II), Hf(IV), Ni, Mn, V, Y(III), Cu(II), Cu(I), Zn(II), Zr(IV), Cd, Ag(I), Ni / Co, lanthanides, actinides, such as Lu, Tb(III), Dy(III), Ho(III), Er(III), Yb(III). The secondary building unit (SBU) may include 3, 4, 5, 6, 8, 9, 10, 11, 12, 15 or 16 extension points.

[0273] The SBUs or nodes may be transition metal carboxylate clusters. The SBUs or nodes may be one or more selected from the group consisting of Zn4O(COO)6, Cu2(COO)4, Cr3O(H2O)3(COO)6, and Zr6O4(OH)10(H2O)6(COO)6), Mg2(OH2)2(COO), RE4(μ3-O)2(COO)8, RE4(μ3-O)2, where RE is Y(III), Tb(III), Dy(III), Ho(III), Er(III) and / or Yb(III). The structure of the SBUs may be characterized by X-ray diffraction using methods well known to those skilled in the art.

[0274] Organic linkers suitable for use in the present invention include those operable to be used to form MOFs for water treatment, molecular separation, and biofiltration related applications. Such linkers may form strong bonds to the metal core, provide large pore size, provide high porosity, and provide selective absorption and / or capacity.

[0275] The organic linkers of the MOFs may be formed from a wide range of organic molecules, such as one or more carboxylate linkers; N-heterocyclic linkers; phosphonate linkers; sulfonate linkers, metallolinkers, such as carboxylate-metallolinkers; and mixtures and derivatives thereof.

[0276] The organic linker may include one or more of a ditopic, tritopic, tetratopic, hexatopic, or octatopic functional linker. The organic linker may include a desymmetrizing linker.

[0277] MOFs suitable for use in the present invention include those operable for use in water treatment, molecular separation, biofiltration, and related applications. Suitable MOFs are preferably water and chemically stable. MOFs may have water-insoluble linkers, and / or solvent-stable linkers, and / or strong covalent bonds between SBUs and linkers, and / or multiple covalent bonds between SBUs and linkers. Water and chemical stability may mean that MOFs do not completely decompose into linkers and SBUs in the presence of water and / or chemicals. Suitable MOFs may have covalent bonds between linkers and SBUs or nodes, and / or coordinate bonds between linkers and SBUs or nodes.

[0278] Suitable MOFs may have a high surface area and / or large pore size. 2 / g, for example 100 to 9,000m 2 / g, preferably 100 to 8,000 m 2 / g or 500~8,000m 2 The surface area may be measured using the well-known Brunauer, Emmett and Teller (BET) technique. The MOF according to any aspect of the present invention is preferably in the form of porous flakes or particles, and may have an average pore size of 0.1 nm to 1000 nm, 0.1 to 950 nm, 0.2 to 900 nm, 0.2 to 850 nm, preferably 0.2 to 800 nm, 0.3 to 700 nm, preferably 0.4 to 650, 0.4 to 550 nm, 0.5 to 500 nm, 0.5 to 450 nm, 0.2 nm to 100 nm, for example 0.2 nm to 90 nm, 0.3 nm to 75 nm, 0.4 nm to 50 nm, for example 0.4 nm to 40 nm, 0.4 nm to 30 nm, or 0.4 nm to 20 nm, preferably 0.4 nm to 15 nm, 0.4 nm to 10 nm.

[0279] The MOF may include a pillared-layer MOF. Suitably, in a pillared-layer MOF, the 2D sheet serves as a scaffold for an organic linker, such as a dipyridyl linker. Advantageously, this is a -SO3 2- This allows for the incorporation of a variety of functional groups into MOFs, such as SO3 2- The use of groups can induce strong acid-base interactions with polar environments and acidic guests such as CO. Furthermore, different pillar linker groups such as -N=N- compared to -CH=CH- provide different selectivities towards HO and methanol.

[0280] The MOF may include functional groups. The MOF may be particularly suitable for water treatment, molecular separation, and biofiltration related applications, with MOFs preferably including functional groups on one or more of the organic linkers. The functional groups may provide selectivity and / or increase pore size for high adsorption capacity or high flux rate. Functional groups include -NH2, -Br, -Cl, -I, -(CH2) n -CH3 (wherein n is 1 to 10), for example, may be selected from one or more of the group consisting of CH3CH2CH2O-, CH3CH2CH2CH2O-, ben-C4H4, methyl, -COOH, and -OH. For example, the MOF may be IRMOF, such as IRMOF-1, IRMOF-2, IRMOF-3, IRMOF-4, IRMOF-5, IRMOF-6, IRMOF-7, IRMOF-8, IRMOF-9, IRMOF-10, IRMOF-16, IRMOF-11, IRMOF-12, IRMOF-13, IRMOF-14, IRMOF-15; and / or CAU, such as CAU-10-OH, CAU-10-NH2, CAU-10-H, CAU-10-CH3; and / or MIL-125-NH2; and / or UiO-66(Zr)-(CH3)2.

[0281] The coating may be operable to provide size exclusion filtration, fouling resistance, and / or adsorption, eg, size exclusion and fouling resistance.

[0282] The pore size of the MOF can be adjusted by using different types of MOFs or different organic linkers with different lengths. For example, the pore size of the MOF can be at least 0.6 nm (e.g., ZIF-78), such as at least 0.8 nm (e.g., ZIF-81), or at least 0.9 nm (e.g., ZIF-79), or at least 1.2 nm (e.g., ZIF-69), or at least 1.3 nm (e.g., ZIF-68), or at least 1.6 nm (e.g., ZIF-82), such as at least 1.8 nm (e.g., ZIF-70), or at least 1.8 nm (e.g., IRMOF-10), or at least 2.8 nm (e.g., MOF-177).

[0283] The MOF may include MOF-74 that has been adapted by replacing one or more of the original linkers containing one phenyl ring with linkers containing 2, 3, 4, 5, 6, 7, 9, 10, or 11 phenyl rings. Such adaptations can change the pore size from about 1.4 nm to about 2.0 nm, about 2.6 nm, about 3.3 nm, about 4.2 nm, about 4.8 nm, about 5.7 nm, about 7.2 nm, about 9.5 nm, respectively.

[0284] The MOF may be hydrophobic. The hydrophobic MOF may be selected from one or more of MIL-101(Cr), NiDOBDC, HKUST-1, Al(OH)(2,6-ndc) (ndc is naphthalene dicarboxylate), MIL-100-Fe, UiO-66, ZIF family, such as ZIF 71, ZIF 74, ZIF-1, ZIF-4, ZIF-6, ZIF-11, ZIF-9, and ZIF 8. Advantageously, the use of such MOFs can improve the fouling resistance of the membrane.

[0285] The MOF may comprise an adsorption-promoting MOF, such as UiO-66 or UiO-66-NH2, preferably UiO-66-NH2, which have been found to adsorb cationic dyes from aqueous solutions more effectively than anionic dyes due to favorable electrostatic interactions between the adsorbent and the cationic dyes. In particular, UiO-66-NH2 has been found to provide a much higher adsorption capacity for cationic dyes and a lower adsorption capacity for anionic dyes than UiO-66.

[0286] The MOF may comprise nanochannels, suitably the MOF is in the form of a flake or particle comprising nanochannels. The average nanochannel diameter may be from 0.2 nm to 100 nm, such as from 0.2 to 90 nm, from 0.3 nm to 75 nm, from 0.4 nm to 50 nm, such as from 0.5 nm to 40 nm, from 0.5 nm to 30 nm, or from 0.5 nm to 20 nm, suitably from 0.5 nm to 15 nm, from 0.5 nm to 10 nm or preferably from 0.5 nm to 8 nm.

[0287] The MOF may contain functional groups selected from one or more of amines, aldehydes, alkynes, and / or azides. The MOF pores may be modified for selective sieving and to provide higher efficiency by post-synthetic modification, preferably on the linkers and / or secondary building blocks / nodes, such as by covalent attachment of amine, or aldehyde, or alkyne, or azide functional groups. Specific functional groups may be introduced into the MOF for specific applications. For example, adding -NH2 to UiO-66 to make UiO-66-NH2 has been found to improve ferric acid adsorption, and sulfone-containing groups are added to iso-IRMOF-16 by oxidation, for example, using dimethyldioxirane, to create a compatible interaction between the coating and the first support moiety.

[0288] The MOFs of the present invention may be synthesized according to the required properties or may be purchased from a commercial supplier. Suitable commercially available metal-organic framework materials can be purchased from BASF, Sigma-Aldrich, or Strem Chemicals.

[0289] The methods used to synthesize the MOFs of the present invention are conventional in the art and may be solvothermal synthesis, microwave-assisted synthesis, electrochemical synthesis, etc.

[0290] A modulator may be used during the synthesis of the MOF to control the MOF particle size, and the modulator may be benzoic acid.

[0291] The MOFs may be in the form of a crystallized continuous phase or particles or flakes that are compressed and interact with or fuse together to form a coating. Preferably, the MOFs are in the form of particles or flakes.

[0292] The size distribution of the MOF flakes or particles may be such that at least 30% by weight of the MOF flakes or particles have a size of 1 nm to 10000 nm, for example 2 to 7500 nm, 5 nm to 5000 nm, 10 nm to 4000 nm, for example 15 nm to 3500 nm, 20 nm to 3000 nm, or 25 nm to 3000 nm, suitably 30 nm to 2500 nm, 40 nm to 2500 nm or preferably 50 nm to 2500 nm, more preferably at least 40% by weight, 50% by weight, 60% by weight, 70% by weight, most preferably at least 80% by weight or at least 90% by weight or 95% by weight or 98% by weight or 99% by weight have a size in the above ranges. The size and size distribution of the MOFs may be measured using transmission electron microscopy (TEM, JEM-2100F, JEOL, Japan).

[0293] For example, the lateral size of the two-dimensional layers across a sample of MOFs may be measured using transmission electron microscopy (TEM, JEM-2100F, JEOL, Japan), and similarly sized nanosheets (M i ) number (N i ) may be measured. The average size may then be calculated according to Equation 1.

number

[0294] The coating may include additives to tailor the properties of the coating, such as other metals; and / or fibers, such as metal oxide nanostrands; and / or dopants, such as Au, Fe, Cu, Cu(OH)2, Cd(OH)2, and / or Zr(OH)2. Such additives may be added to the membrane to control the pore size and channel structure of the MOF and / or to generate nanochannels for high water flux rates. Any type of suitable fibers, such as continuous or staple fibers (staple fibers) having a diameter of 0.1 nm to 1000 nm, e.g. 0.1 to 850 nm, 0.5 to 500 nm, or 0.5 to 100 nm, 0.75 to 75 nm, preferably 0.75 to 50 nm, may be incorporated into the membrane. Suitably, the fibers are removed prior to use, such as by mechanical removal or dissolution.

[0295] Further details of the conferring method are disclosed in published PCT patent application WO 2019 / 186134, specifically in paragraphs

[0117] ,

[0118] and

[0126] to

[0130] , inclusive. The entire contents of paragraphs

[0117] ,

[0118] and

[0126] to

[0130] , inclusive, are hereby incorporated by reference in their entirety.

[0296] Further details of the coating composition are disclosed in published PCT patent application WO 2019 / 186134, specifically at paragraphs

[97] to

[0116] , inclusive, the entire contents of which are hereby incorporated by reference in their entirety.

[0297] The coating may further include nanochannels formed by the use of fibers in the manufacture of the coating. Advantageously, the presence of nanochannels within the coating has been found to significantly increase water flux by incorporating continuous or chopped fibers having diameters of 0.5-1000 nm during the manufacturing process and subsequent removal of the fibers.

[0298] The nanochannels in the coating may have a diameter of 1-750 nm, such as 1-500 nm, or 1-250 nm, for example 1-150 nm or 1-100 nm, such as 1-50 nm or 1-25 nm, for example 1-10 nm or preferably 1-5 nm.

[0299] The two-dimensional material of the coating may be a treated two-dimensional material. The two-dimensional material may be treated after the formation of the coating. The treatment may cause changes in the functional groups of the two-dimensional material, such as by applying high energy radiation, such as laser radiation, chemicals, heat, thermal, and / or pressure to the two-dimensional material.

[0300] The two-dimensional material may be treated, suitably reduced, by exposing the two-dimensional material to radiation, such as laser radiation, microwave radiation, UV radiation, electron beam radiation, plasma treatment, electron radiation, soft x-ray radiation, gamma radiation, alpha radiation; chemical treatment, pressure treatment and / or heat treatment, preferably laser radiation and / or plasma treatment.

[0301] The coating may comprise multiple coating layers, at least one of which has been treated prior to deposition of a subsequent layer. Preferably, each layer has been treated prior to deposition of a subsequent layer. The layers of a coating layer comprising multiple coating layers may have been subjected to different treatments in terms of type and / or extent of treatment. Thus, at least one of the layers may comprise a two-dimensional material having a different functionality than another layer. For example, the layer may comprise a gradient of reduction levels of the two-dimensional material that decrease from the top of the coating layer to the bottom of the coating layer adjacent the membrane. The gradient may be generated in the opposite direction.

[0302] The presence of a gradient may increase adhesion between the coating and the substrate and may also increase the fouling resistance of the overall film.

[0303] The treatment of the two-dimensional material on the membrane may cause a change in the functional groups of the two-dimensional material, such as a change in the number, type and / or distribution of functional groups. For example, the treatment may reduce the two-dimensional material and / or functionalize the two-dimensional material by adding functional groups to the two-dimensional material.

[0304] Treatment of the two-dimensional material of the membrane to functionalize the two-dimensional material may add or change functional groups of the two-dimensional material, for example by reaction with existing hydroxyl, carboxyl and / or epoxide groups of the two-dimensional material. Functionalization includes covalent and non-covalent modification. Covalent modification methods can be subclassified into nucleophilic substitution reactions, electrophilic substitution reactions, condensation reactions and addition reactions.

[0305] The two-dimensional material may be treated, suitably reduced, by exposing the two-dimensional material to radiation, such as laser radiation, microwave radiation, UV radiation, electron beam radiation, plasma treatment, electron radiation, soft x-ray radiation, gamma radiation, alpha radiation; chemical treatment and / or thermal treatment, preferably laser radiation and plasma treatment.

[0306] Chemical, thermal or radiation treatment of the 2D materials on the membrane can be used to form chemically reduced GO (CRGO), thermally reduced graphene oxide (TRGO) or radiation reduced graphene oxide (RRGO).

[0307] The hydrophilicity of the treated membrane may be controlled by the percentage of functional groups or polar atoms such as oxygen or nitrogen that remain on the surface after treatment.

[0308] Membranes may be used in the treatment and separation of water from contaminants.

[0309] The membranes may be used in chemical separations, protein separations, produced water treatment or industrial wastewater treatment requiring high temperature operation and / or harsh pH environments.

[0310] The membranes of the present invention may be operable for use in applications requiring efficient removal of suspended solid particulates from a feed solution in an energy efficient manner. Thus, the membranes may be operable for use in applications such as, but not limited to, algae concentration, high solids juice concentration and clarification, protein separation from milk, produced water / wastewater clarification, enzyme concentration, sugar refining, such as separation of calcium carbonate from sugar feedstock, extraction of valuable metals such as lithium, tungsten, gold and / or silver.

[0311] The membranes according to the invention may be operable for use in desalination; for the separation of sodium, magnesium, molybdenum and / or lithium.

[0312] In the membranes of the present invention, pressure may be used to force water through the membrane section where contaminants are separated and left in the water feed and uncontaminated water passes through to the permeate side, where uncontaminated water is forced through the membrane towards the permeate outlet.

[0313] The membranes may be operable for use in applications requiring efficient removal of suspended solid particulates from a feed solution in an energy efficient manner. Thus, the membranes may be operable for use in applications such as, but not limited to, algae concentration, high solids juice concentration and clarification, protein separation from milk, produced water / wastewater clarification, enzyme concentration, sugar refining, such as separation of calcium carbonate from sugar feedstock, extraction of critical metals such as lithium, tungsten, gold and / or silver.

[0314] The membranes may be operable for use in applications requiring efficient removal of divalent and trivalent cations from a feed solution in an energy efficient manner. Thus, the membranes may be operable for use in applications such as, but not limited to, water softening, extraction of critical metals, etc.

[0315] The membrane may be a microfiltration membrane (MF) which may be used in the area, for example, to remove bacteria, cysts, yeast cells, suspended particles, pigments, and asbestos.

[0316] The membrane may be an ultrafiltration membrane (UF), which may be used in the area, for example, to remove proteins, colloidal particles and viruses.

[0317] The membrane may be a nanofiltration membrane (NF) which may be used in the area to select for example multivalent ions, dissolved compounds, medium sized organic molecules, small proteins, small colloidal particles.

[0318] According to a further aspect of the present invention there is provided a separation part for use in an apparatus for reducing the ratio of divalent ions to monovalent ions in an aqueous solution from a source aqueous solution having a higher ratio of divalent ions to monovalent ions, the separation part comprising a membrane according to any of the aspects of the present invention.

[0319] An apparatus for reducing the ratio of divalent ions to monovalent ions in an aqueous solution from a source aqueous solution having a higher ratio of divalent ions to monovalent ions, comprising: Optionally, a pre-filtration portion operable to receive the raw aqueous solution and produce a pre-filtered aqueous solution; a first separation portion operable to receive said optionally prefiltered aqueous solution and form an intermediate aqueous solution having a lower ratio of divalent ions to monovalent ions than the optionally prefiltered aqueous solution; and / or a second separation section operable to receive the intermediate aqueous solution and form an aqueous product solution having a lower ratio of divalent ions to monovalent ions than the intermediate solution; may include:

[0320] The separation portion comprising the membrane according to any aspect of the invention may be a pre-filtration portion, a first and / or a second separation portion, for example a pre-filtration portion and / or a first separation portion.

[0321] According to a further aspect of the present invention, there is provided an apparatus for reducing the ratio of divalent ions to monovalent ions in an aqueous solution from a source aqueous solution having a higher ratio of divalent ions to monovalent ions, comprising: Optionally, a pre-filtration portion operable to receive the raw aqueous solution and produce a pre-filtered aqueous solution; a first separation portion operable to receive said aqueous solution, optionally prefiltered, and form an intermediate aqueous solution having a lower ratio of divalent ions to monovalent ions than said aqueous solution, optionally prefiltered; and / or a second separation section operable to receive the intermediate aqueous solution and form an aqueous product solution having a lower ratio of divalent ions to monovalent ions than the intermediate solution; wherein the pre-filtration section, the first and / or the second separation section comprise a separation section comprising a membrane according to any aspect of the present invention.

[0322] According to a further aspect of the invention there is provided a process for reducing the ratio of divalent ions to monovalent ions in an aqueous solution comprising the steps of: a. optionally contacting a source aqueous solution containing divalent ions and monovalent ions with a pre-filtration portion operable to produce a pre-filtered aqueous solution; b. contacting the optionally prefiltered aqueous solution with a first separation portion to form an intermediate aqueous solution having a lower ratio of divalent ions to monovalent ions than the optionally prefiltered aqueous solution; c. contacting the intermediate solution with a second separation portion to form an aqueous product solution having a lower ratio of divalent ions to monovalent ions than in the intermediate solution; wherein the pre-filtration section, the first and / or the second separation section comprise a separation section comprising a membrane according to any aspect of the present invention.

[0323] According to a further aspect of the invention there is provided an aqueous product solution obtained by the process for reducing the ratio of divalent ions to monovalent ions in an aqueous solution of the invention.

[0324] The separation sections, apparatus and / or processes of embodiments of the present invention may be for use in the extraction of valuable metals, for example for the extraction of lithium, tungsten, tin, gold and / or silver.

[0325] The separation portion, apparatus and / or process of the embodiments of the invention may be for use in lithium extraction, e.g., direct lithium extraction (DLE). The aqueous solution obtainable by the apparatus and / or obtained by the process of the invention may be operable to produce an aqueous solution containing monovalent ions, such as lithium, in an amount of 100 ppm or more, substantially free of divalent ions, and with a purity of 99.5% or more when dried. As used herein, "substantially free of divalent ions" may mean that divalent ions are present in an amount less than 10 ppm, e.g., less than 5 ppm or less than 1 ppm.

[0326] The first separation portion may comprise a nanofiltration membrane according to any aspect of the present invention.

[0327] The nanofiltration membrane may have a divalent ion rejection of 70% or more, such as 80% or more or 90% or more. The nanofiltration membrane may have a divalent ion rejection of 99% or less, such as 98% or less or 95% or less.

[0328] The nanofiltration membrane may have a rejection for monovalent ions of 50% or less, such as 40% or less or 30% or less.

[0329] The second separation portion may comprise an ion exchange resin.

[0330] The ion exchange resin of the second separation portion may comprise a microporous (gel type) and / or a macroporous (porous type) resin.

[0331] The ion exchange resin of the second separation section may comprise a macroporous (porous type) resin.

[0332] The ion exchange resin of the second separation section may be weakly acidic, for example by including carboxylic acid functional groups.

[0333] The exchange resin of the second separation section may comprise chelating groups such as iminodiacetic acid groups, thiourea groups, aminomethylphosphonic acid groups, and / or di-2-ethylhexyl phosphate (D2EHPA) groups, and / or residues thereof. The exchange resin of the second separation section may comprise chelating iminodiacetic acid groups or residues thereof.

[0334] The ion exchange resins may comprise polymers that contain a polystyrene and / or a polyacrylic backbone and / or that contain sulfonic acid and / or carboxylic acid functional groups. Some examples of commercially available resins include Lanxess Lewatit TP 207, Lewatit TP 208, Amberlite IRC 748, Purolite S 930 (weakly acidic macroporous cation exchange resin with chelating iminodiacetic acid groups); Lanxess Lewatit TP 214 (weakly acidic macroporous cation exchange resin with chelating thiourea groups); Lanxess Lewatit TP 260 (weakly acidic macroporous cation exchange resin with chelating aminomethylphosphonic acid groups); and / or Lanxess Lewatit VP OC1026 (weakly acidic macroporous cation exchange resin with chelating di-2-ethylhexyl phosphate (D2EHPA) groups).

[0335] The raw aqueous solution may be obtained from a salt water (brine) source or from hard rock containing monovalent ions. The raw aqueous solution may be a seawater brine, a saline lake brine, a shallow groundwater brine, a geothermal brine, a deep sedimentary basin brine, or an industrial brine. The raw aqueous solution may be a geothermal brine, such as a geothermal brine obtained from a deep or shallow geothermal source. The raw aqueous solution may be a leachate produced following processing, e.g., roasting, of a mineral rock source, such as spodumene mineral.

[0336] The source aqueous solution may be marine saltwater; shallow brine beneath a dry lake, e.g., from Clayton Valley, Nevada and / or the Salar de Olaroz mine (Argentina); geothermal brine, e.g., from Cornwall, UK and / or the Salton Sea, California; and / or deep brine, e.g., from the Paradox Basin, Utah.

[0337] The raw aqueous solution may be deep or shallow geothermal brine, such as from Cornwall, UK and / or the Salton Sea, California. The raw aqueous solution may be deep geothermal brine, such as from Cornwall, UK. Deep geothermal brine may be defined as brine extracted from a depth greater than 150m. Shallow geothermal brine may be defined as brine extracted from a depth of 150m or less.

[0338] The source solution may contain divalent cations, and optionally trivalent cations, such as Ca, Mg, B, Ba, Fe, Mn, Zn, Mo, Sr, Zr, V, Cr, Te, Ti, Ga, Hg, Be, In, Ta, Ce, Hf, Sm, La, Nb, Th, Al, Tl, As, Ni, Cu, Sc, Sn, Sb, Co, Pb, U, Cd, Y and / or Bi, preferably Ca, Mg and / or B.

[0339] The monovalent ions of the original solution may include cations such as Na, K, Li, Cs, Rb, W, Au and / or Ag. Preferably, the monovalent ions of the original solution include Li, W, Au, Ag, Na and / or K, more preferably Li, W, Au and / or Ag, most preferably Li. The original solution may include anions such as Cl, F, Br, SO4, HCO3 and / or CO3. The original solution may preferably include Cl and / or SO4.

[0340] The raw solution may comprise total suspended solids in an amount of 1 ppm or more, such as 5 ppm or more or 50 ppm or more. The raw solution may comprise total suspended solids in an amount of 2000 ppm or less, such as 1500 ppm or less or 1000 ppm or less or 500 ppm or less. The raw solution may comprise a ratio of divalent ions to monovalent ions of ≦500:1, such as ≦250:1, or such as ≦150:1. The raw solution may comprise divalent ions in an amount of 80,000 ppm or less, such as 50,000 ppm or less or 30,000 ppm or less. The raw solution may comprise monovalent ions in an amount of 3000 ppm or less, such as 2000 ppm or less or 1000 ppm or less. The raw solution may comprise a ratio of divalent ions to monovalent ions of ≧0.5:1, such as ≧5:1, such as ≧8:1, or such as ≧12:1. The original solution may contain a ratio of divalent ions to monovalent ions of ≦200:1, such as ≦100:1, or such as ≦50:1. The original solution may contain divalent ions in an amount of 1,000 ppm or more, such as 2,000 ppm or more or 3,000 ppm or more. The original solution may contain divalent ions in an amount of 10,000 ppm or less, such as 5,000 ppm or less or 4,000 ppm or less. The original solution may contain monovalent ions in an amount of 50 ppm or more, such as 150 ppm or more or 200 ppm or more. It will be understood that the aqueous solution may contain other monovalent ions in addition to the monovalent ions of interest. The original solution may contain monovalent ions in an amount of 2000 ppm or less, such as 1000 ppm or less or 500 ppm or less.

[0341] The prefiltered aqueous solution may contain divalent cations and optionally trivalent cations, such as Ca, Mg, B, Ba, Fe, Mn, Zn, Mo, Sr, Zr, V, Cr, Te, Ti, Ga, Hg, Be, In, Ta, Ce, Hf, Sm, La, Nb, Th, Al, Tl, As, Ni, Cu, Sc, Sn, Sb, Co, Pb, U, Cd, Y and / or Bi, preferably Ca, Mg and / or B. The monovalent ions of the original solution may contain cations such as Na, K, Li, Cs, Rb, W, Au and / or Ag. Preferably, the monovalent ions of the prefiltered solution include Li, W, Au, Ag, Na and / or K, more preferably Li, W, Au and / or Ag, most preferably Li. The original solution may contain anions such as Cl, F, Br, SO4, HCO3 and / or CO3. The original solution may preferably contain Cl and / or SO4.

[0342] The prefiltered aqueous solution may contain less total suspended solids, such as silica, bacteria, and / or oil / grease, than the original aqueous solution. The prefiltered aqueous solution may contain less than 100 ppm total suspended solids, such as less than 50 ppm or less, or less than 10 ppm.

[0343] The prefiltered aqueous solution may comprise a ratio of divalent ions to monovalent ions of ≦500:1, such as ≦250:1, or such as ≦150:1. The prefiltered aqueous solution may comprise divalent ions in an amount of 80,000 ppm or less, such as ≦50,000 ppm or less or ≦30,000 ppm.

[0344] The prefiltered aqueous solution may contain monovalent ions in an amount of 3000 ppm or less, such as 2000 ppm or less or 1000 ppm or less. The prefiltered aqueous solution may contain substantially the same amounts of divalent and monovalent ions as the original aqueous solution.

[0345] The prefiltered solution may comprise a ratio of divalent ions to monovalent ions of ≧0.5:1, such as ≧5:1, such as ≧8:1, or such as ≧12:1. The prefiltered solution may comprise a ratio of divalent ions to monovalent ions of ≦200:1, such as ≦100:1, or such as ≦50:1. The prefiltered solution may comprise divalent ions in an amount of 1,000 ppm or more, such as ≧2,000 ppm or more or ≧3,000 ppm or more. The prefiltered solution may comprise divalent ions in an amount of 10,000 ppm or less, such as ≦5,000 ppm or less or ≦4,000 ppm or less. The prefiltered solution may comprise monovalent ions in an amount of 50 ppm or more, such as ≧150 ppm or more or ≧200 ppm. It will be appreciated that the aqueous solution may comprise other monovalent ions in addition to the monovalent ions of interest. The prefiltered solution may contain monovalent ions in an amount of 2000 ppm or less, such as 1000 ppm or less or 500 ppm or less.

[0346] The intermediate solution may contain divalent cations, and optionally trivalent cations, such as Ca, Mg, B, Ba, Fe, Mn, Zn, Mo, Sr, Zr, V, Cr, Te, Ti, Ga, Hg, Be, In, Ta, Ce, Hf, Sm, La, Nb, Th, Al, Tl, As, Ni, Cu, Sc, Sn, Sb, Co, Pb, U, Cd, Y and / or Bi, preferably Ca, Mg and / or B.

[0347] The monovalent ions of the intermediate source solution may include cations such as Na, K, Li, Cs, Rb, W, Au, and / or Ag. Preferably, the monovalent ions of the intermediate solution include Li, W, Au, Ag, Na, and / or K, more preferably Li, W, Au, and / or Ag, most preferably Li. The intermediate source solution may include anions such as Cl, F, Br, SO4, HCO3, and / or CO3. The source solution may preferably include Cl and / or SO4.

[0348] The intermediate solution may comprise a ratio of divalent ions to monovalent ions of ≦100:1, such as ≦50:1, or such as ≦30:1. The intermediate solution may comprise divalent ions in an amount of 16,000 ppm or less, such as ≦10,000 ppm or less or ≦6,000 ppm or less. The intermediate solution may comprise monovalent ions in an amount of 2,700 ppm or less, such as ≦1,800 ppm or less or ≦900 ppm or less. The intermediate solution may comprise a ratio of divalent ions to monovalent ions of ≧1:2, such as ≧1:1, or such as ≧1.2:1. The intermediate solution may comprise a ratio of divalent ions to monovalent ions of ≦10:1, such as ≦5:1, or such as ≦3:1. The intermediate solution may comprise divalent ions in an amount of 100 ppm or more, such as ≧200 ppm or more or ≧300 ppm. The intermediate solution may contain divalent ions in an amount of 2,000 ppm or less, such as 500 ppm or less or 400 ppm or less. The intermediate solution may contain monovalent ions in an amount of 40 ppm or more, such as 120 ppm or more or 160 ppm or more. It will be understood that the aqueous solution may contain other monovalent ions in addition to the monovalent ions of interest. The intermediate solution may contain monovalent ions in an amount of 1,600 ppm or less, such as 800 ppm or less or 400 ppm or less.

[0349] The product solution may include divalent cations and optionally trivalent cations, such as Ca, Mg, B, Ba, Fe, Mn, Zn, Mo, Sr, Zr, V, Cr, Te, Ti, Ga, Hg, Be, In, Ta, Ce, Hf, Sm, La, Nb, Th, Al, Tl, As, Ni, Cu, Sc, Sn, Sb, Co, Pb, U, Cd, Y and / or Bi, preferably Ca, Mg and / or B. The monovalent ions of the original solution may include cations such as Na, K, Li, Cs, Rb, W, Au and / or Ag. Preferably, the monovalent ions of the product solution include Li, W, Au, Ag, Na and / or K, more preferably Li, W, Au and / or Ag, most preferably Li. The original solution may include anions such as Cl, F, Br, SO4, HCO3 and / or CO3. The original solution may preferably contain Cl and / or SO4.

[0350] The product solution may comprise a ratio of monovalent ions to divalent ions of ≧100:1, such as ≧200:1, or ≧300:1. The product solution may comprise divalent ions in an amount of 3 ppm or less, such as ≦2 ppm or less or ≦1 ppm. The product solution may comprise monovalent ions in an amount of 40 ppm or more, such as ≧120 ppm or more or ≧160 ppm. It will be understood that the aqueous solution may comprise other monovalent ions in addition to the monovalent ions of interest. The product solution may comprise monovalent ions in an amount of ≦1,600 ppm, such as ≦800 ppm or less or ≦400 ppm.

[0351] The apparatus and / or process of the present invention may be operable to produce an aqueous product solution having a retention of monovalent ions, such as lithium, of 65% or more, such as 70% or more or 75% or more, compared to the amount of monovalent ions, such as lithium, in the source aqueous solution.

[0352] The apparatus and / or process of the present invention may include a further separation section operable to receive the raw product solution after the second separation section.

[0353] This further separation section may include a separation material operable to select a particular type of monovalent ion. For example, the further separation section may include a lithium-specific separation material, such as an absorbent or extractant, operable to extract Li+ from the remaining monovalent cations, such as Na+.

[0354] The further separation portion may comprise a (further, if an ion exchange separation portion is already present) ion exchange separation portion.

[0355] The apparatus and / or process of the present invention may include further ion exchange separation sections suitably operable to receive the aqueous product solution after the "first" ion exchange separation section.

[0356] The (further) ion exchange separation portion may be operable to separate the monovalent ion of interest from other types of monovalent ions. The (further) ion exchange separation portion may include a separation member operable to select a particular type of monovalent ion. For example, the (further) ion exchange separation portion may include a lithium-specific separation member, such as an ion exchange resin, operable to extract Li+ from other monovalent cations different from the monovalent ion of interest, such as Na+ and K+.

[0357] The (further) ion exchange separation section may be operable to receive the aqueous product solution and form a further purified aqueous product solution having a lower ratio of different types of monovalent ions to the monovalent ion of interest. The purified aqueous product solution may be formed by recovery of the eluent in the (further) ion exchange separation section. Thus, the monovalent ion of interest may be retained in the eluent and other monovalent ions may be removed with the effluent.

[0358] In the process of the present invention, the process comprises: d. contacting the product solution with a (further) ion exchange separation section to form a purified aqueous product solution having a lower ratio of different types of monovalent ions to the monovalent ion of interest. It may further include.

[0359] The (further) ion exchange resin of the ion exchange separation section may comprise an ion exchange resin. The (further) ion exchange resin of the ion exchange separation section may comprise a microporous (gel type) and / or a macroporous (porous type) resin.

[0360] The (further) ion exchange resin may comprise a macroporous (porous type) resin.

[0361] The (further) ion exchange resin may have a retention / adsorption level for the monovalent ion of interest of 80% or more, such as 95% or more or 99.9% or more.

[0362] The (further) ion exchange resin may have a retention / adsorption rate for monovalent ions other than the monovalent ion of interest of 20% or less, such as 10% or less or 5% or less.

[0363] The purified product solution may include divalent cations and optionally trivalent cations, such as Ca, Mg, B, Ba, Fe, Mn, Zn, Mo, Sr, Zr, V, Cr, Te, Ti, Ga, Hg, Be, In, Ta, Ce, Hf, Sm, La, Nb, Th, Al, Tl, As, Ni, Cu, Sc, Sn, Sb, Co, Pb, U, Cd, Y and / or Bi, preferably Ca, Mg and / or B. The monovalent cations of interest of the purified product solution may include Na, K, Li, Cs, Rb, W, Au and / or Ag. Preferably, the monovalent cations of interest of the product solution include Li, W, Au, Ag, Na and / or K, more preferably Li, W, Au and / or Ag, most preferably Li. The purified product solution may include anions such as Cl, F, Br, SO4, HCO3, and / or CO3. The product solution may preferably contain Cl and / or SO4.

[0364] The purified product solution may comprise divalent ions in an amount of 10 ppm or less, such as 7 ppm or less or 5 ppm or less. The purified product solution may comprise divalent ions in an amount of 3 ppm or less, such as 2 ppm or less or 1 ppm or less. The purified product solution may comprise monovalent ions of interest in an amount of 40,000 ppm or less, such as 10,000 ppm or less or 5,000 ppm or less. The purified product solution may comprise monovalent ions of interest in an amount of 100 ppm or more, such as 500 ppm or more or 1,000 ppm or more. It will be understood that the purified product solution may comprise other monovalent ions in addition to the monovalent ions of interest. The majority of the monovalent ions may be the monovalent ions of interest. The purified product solution may comprise a ratio of divalent ions to monovalent ions of interest of ≦0.02:1, such as ≦0.01:1, or such as ≦0.005:1. The purified product solution may include a ratio of the different type of monovalent ion to the monovalent ion of interest of ≦10:1, such as ≦5:1, or ≦1:1. This range may also apply to all other types of monovalent ions / cations that are not the monovalent ion / cation of interest. The purified product solution may include a ratio of the different type of monovalent ion to the monovalent ion of interest of ≦0.1:1, such as ≦0.05:1, or such as ≦0.01:1. This range may also apply to all other types of monovalent ions / cations that are not the monovalent ion / cation of interest.

[0365] The apparatus and / or process of any aspect of the invention may include a concentrating portion operable to receive the (purified) aqueous product solution and reduce the water content of the solution, e.g. to produce a concentrated aqueous product solution. The concentrating portion may include a membrane according to any aspect of the invention. The concentrating portion may include a reverse osmosis membrane.

[0366] Advantageously, the use of reverse osmosis membranes may provide an efficient means of concentrating a high purity monovalent ion solution, such as lithium, before lithium carbonate is produced by evaporation / precipitation / crystallization.

[0367] In the process of the present invention, the process comprises: contacting the (purified) product solution with a concentrating portion operable to receive the (purified) aqueous product solution and reduce the water content of the solution, e.g., to produce a concentrated aqueous product solution; It may further include.

[0368] The concentrated portion may be contacted with the purified product solution as step (e).

[0369] The apparatus and / or process of the present invention may be operable to produce an aqueous product solution (product solution, purified product solution and / or concentrated product solution) having a retention of 65% or more, such as 70% or more or 75% or more of a monovalent ion of interest, such as lithium, compared to the amount of the monovalent ion of interest, such as lithium, in the raw aqueous solution.

[0370] The apparatus and / or process of the present invention may be operable to form concentrated product solutions having a solids content of 0.5% or more, such as 2% or more, or 5% or more.

[0371] The apparatus and / or process of the present invention may be operable to form a concentrated product solution containing 10% or more by solids, such as 20% or more by solids, or 50% or more of a monovalent ion / compound of interest, such as lithium / lithium compounds.

[0372] The apparatus and / or process of the present invention may be operable to form a concentrated product solution containing 90% or more by solids, such as 95% or more by solids, of the monovalent ion / compound of interest, e.g., lithium / lithium compounds, or 99% or more by solids.

[0373] As used herein, a "lattice structure" refers to a three-dimensional structure made up of one or more repeating unit cells that are interconnected in a manner that allows fluid flow to adjacent cells. Triply periodic surfaces are included as part of the term "lattice."

[0374] As used herein, the term "lamellar structure" refers to a structure of at least two overlapping layers. As used herein, the term "active layer" or "membrane" refers to a porous barrier operable to separate desired dissolved materials (solutes), colloids or particulates from a feed solution. It may represent the interface between the feed and permeate streams. As used herein, the term "two-dimensional material" refers to a material with at least one dimension less than 100 nm.

[0375] As used herein, the term "brine" may refer to an aqueous solution of salt.

[0376] As used herein, the term "nanofiltration" may refer to a separation technique that utilizes membranes to separate different components within a fluid mixture. Nanofiltration membranes may have pore sizes between 1 and 100 nm.

[0377] For the purposes of the present invention, an aliphatic group is a hydrocarbon moiety that may be linear (i.e., unbranched), branched, or cyclic, and may be fully saturated or may contain one or more units of unsaturation, but is not aromatic. The term "unsaturated" refers to a moiety having one or more double and / or triple bonds. Thus, the term "aliphatic" is intended to include alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, or cycloalkenyl groups, and combinations thereof. The term "(hetero)aliphatic" includes both aliphatic and / or heteroaliphatic groups.

[0378] The aliphatic group is optionally 1~30 aliphatic groups, i.e., aliphatic groups having 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30 carbon atoms. 1~15 Aliphatic, optionally C 1~12 Aliphatic, optionally C 1~10 Aliphatic, optionally C 1~8 Aliphatic, e.g. C 1~6Aliphatic Groups. Suitable aliphatic groups include straight-chain or branched alkyl, alkenyl and alkynyl groups, and mixtures thereof, such as (cycloalkyl)alkyl, (cycloalkenyl)alkyl and (cycloalkyl)alkenyl groups.

[0379] The term "alkyl," as used herein, refers to a saturated, straight or branched chain hydrocarbon group derived from an aliphatic moiety by removing a hydrogen atom. An alkyl group may optionally include the group "C 1~20 "Alkyl groups" are alkyl groups that are straight or branched chain having 1 to 20 carbons. Thus, an alkyl group has 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms. Optionally, the alkyl group is 1~15 Alkyl, optionally C 1~12 Alkyl, optionally C 1~10 Alkyl, optionally C 1~8 Alkyl, optionally C 1~6 It is an alkyl group. 1~20Examples of the "alkyl group" include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a sec-pentyl group, an isopentyl group, a n-pentyl group, a neopentyl group, a n-hexyl group, a sec-hexyl group, a n-heptyl group, a n-octyl group, a n-nonyl group, a n-decyl group, a n-undecyl group, a n-dodecyl group, a n-tridecyl group, a n-tetradecyl group, a n-pentadecyl group, a n-hexadecyl group, a n-heptadecyl group, a n-octadecyl group, a n-nonadecyl group, Examples of such groups include an n-eicosyl group, a 1,1-dimethylpropyl group, a 1,2-dimethylpropyl group, a 2,2-dimethylpropyl group, a 1-ethylpropyl group, an n-hexyl group, a 1-ethyl-2-methylpropyl group, a 1,1,2-trimethylpropyl group, a 1-ethylbutyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 1,1-dimethylbutyl group, a 1,2-dimethylbutyl group, a 2,2-dimethylbutyl group, a 1,3-dimethylbutyl group, a 2,3-dimethylbutyl group, a 2-ethylbutyl group, a 2-methylpentyl group, and a 3-methylpentyl group.

[0380] The term "alkenyl" as used herein means a group derived from the removal of one hydrogen atom from a straight or branched chain aliphatic moiety having at least one carbon-carbon double bond. The term "alkynyl" as used herein refers to a group derived from the removal of one hydrogen atom from a straight or branched chain aliphatic moiety having at least one carbon-carbon triple bond. Alkenyl and alkynyl groups each optionally include the moiety "C 2~20 alkenyl" and "C 2~20 alkynyl", optionally with "C 2~15 alkenyl" and "C 2~15 alkynyl", optionally with "C 2~12 alkenyl" and "C 2~12 alkynyl", optionally with "C 2~10 alkenyl" and "C 2~10 alkynyl", optionally with "C 2~8 alkenyl" and "C 2~8 alkynyl", optionally with "C 2~6 alkenyl" and "C 2~6Examples of alkenyl groups include ethenyl, propenyl, allyl, 1,3-butadienyl, butenyl, 1-methyl-2-buten-1-yl, allyl, 1,3-butadienyl, and allenyl. Examples of alkynyl groups include ethynyl, 2-propynyl (propargyl), and 1-propynyl.

[0381] The term "alicyclic", "carbocycle" or "carbocyclic" as used herein refers to a saturated or partially unsaturated cycloaliphatic monocyclic or polycyclic (including fused, bridged, and spiro-fused) ring system having 3 to 20 carbon atoms, i.e., an alicyclic group having 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms. Optionally, the alicyclic group has 3 to 15, optionally 3 to 12, optionally 3 to 10, optionally 3 to 8 carbon atoms, optionally 3 to 6 carbon atoms. The term "alicyclic", "carbocycle" or "carbocyclic" also includes an aliphatic ring fused to one or more aromatic or non-aromatic rings, such as a tetrahydronaphthyl ring, where the point of attachment is on the aliphatic ring. A carbocyclic group may be polycyclic, e.g., bicyclic or tricyclic. It will be understood that alicyclic groups may include alicyclic rings having one or more linked or unlinked alkyl substituents, such as -CH2-cyclohexyl.Specific examples of carbocyclic rings include cyclopropane, cyclobutane, cyclopentane, cyclohexane, bicyclo[2,2,1]heptane, norbornene, phenyl, cyclohexene, naphthalene, spiro[4.5]decane, cycloheptane, adamantane, and cyclooctane.

[0382] Heteroaliphatic groups (including heteroalkyl, heteroalkenyl and heteroalkynyl) are aliphatic groups as described above further containing one or more heteroatoms. Thus, heteroaliphatic groups optionally contain 2-21 atoms, optionally 2-16 atoms, optionally 2-13 atoms, optionally 2-11 atoms, optionally 2-9 atoms, optionally 2-7 atoms, with at least one atom being a carbon atom. The optional heteroatom is selected from O, S, N, P and Si. When a heteroaliphatic group has two or more heteroatoms, the heteroatoms may be the same or different. Heteroaliphatic groups may be substituted or unsubstituted, branched or unbranched, cyclic or acyclic, and include saturated, unsaturated or partially unsaturated groups.

[0383] An alicyclic group is a saturated or partially unsaturated cycloaliphatic monocyclic or polycyclic (including fused, bridged and spiro-fused) ring system having 3 to 20 carbon atoms, i.e., an alicyclic group having 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms. Optionally, the alicyclic group has 3 to 15, optionally 3 to 12, optionally 3 to 10, optionally 3 to 8 carbon atoms, optionally 3 to 6 carbon atoms. The term "alicyclic" encompasses cycloalkyl, cycloalkenyl and cycloalkynyl groups. It will be understood that an alicyclic group may include an alicyclic ring having one or more linked or unlinked alkyl substituents, for example -CH2-cyclohexyl. Specifically, C 3~20 Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, and cyclooctyl.

[0384] An aryl group or ring is a monocyclic or polycyclic ring system having from 5 to 20 carbon atoms, in which at least one ring in the system is aromatic, and in which each ring in the system contains from 3 to 12 ring members. An aryl group is optionally denoted by "C 6~12An aryl group is an aryl group consisting of 6, 7, 8, 9, 10, 11 or 12 carbon atoms, including monocyclic or fused ring groups such as bicyclic ring groups. 6~10 Examples of the "aryl group" include a phenyl group, a biphenyl group, an indenyl group, an anthracyl group, a naphthyl group, and an azulenyl group. In addition, condensed rings such as indane, benzofuran, phthalimide, phenanthridine, and tetrahydronaphthalene are also included in the aryl group.

[0385] As used herein, unless expressly stated otherwise, all numerical values, such as those expressing values, ranges, amounts, or percentages, may be read as if preceded by the word "about," even if the term "about" does not expressly appear. The term "about," as used herein, means ±10% of the stated value.

[0386] The singular includes the plural and vice versa. For example, although this specification refers to "a" channel, "a" dimensional property, etc., one or more of each of these and any other components can be used.

[0387] Also, any numerical range recited herein is intended to include all subranges subsumed therein. The singular includes the plural and vice versa.

[0388] As used herein, the terms "on," "applied on / over," "extend over," "formed on / over," and "provided on / over" mean formed or provided on a surface, but not necessarily in contact with the surface. For example, a coating "formed over" a substrate does not exclude the presence of another coating of the same or different composition located between the formed coating and the substrate.

[0389] As used herein, the terms "comprising" and "comprises" are synonymous with "including" or "containing" and are inclusive or open-ended and do not exclude additional, unrecited members, elements or method steps. In addition, although the invention has been described in terms of "comprising," the invention detailed herein may also be described as "consisting essentially of" or "consisting of."

[0390] As used herein, the term "polymer" refers to oligomers and both homopolymers and copolymers, and the prefix "poly" refers to two or more. "Includes for example" and similar terms mean "includes, but is not limited to, for example."

[0391] As used herein, "average" refers to the mean average, unless otherwise specified.

[0392] When ranges are provided with respect to genus, each range may additionally and independently apply to any one or more of the listed species of that genus.

[0393] All of the features contained in this specification may be combined with any of the above aspects in any combination.

[0394] For a better understanding of the present invention and to show how aspects of the invention may be put into practice, reference is made by way of example to the following data and drawings. [Brief description of the drawings]

[0395] [Figure 1] FIG. 1 shows a perspective view of a first embodiment of a membrane according to the invention, the unit cell of which is based on a TPMS gyroid lattice. [Figure 1A] FIG. 1A shows a perspective side cutaway view of the membrane of FIG. [Diagram 2] FIG. 2 shows a perspective vertical cutaway view of the membrane of FIG. [Diagram 3] FIG. 3 shows a perspective partial cutaway view of the upper portion of the membrane of FIG. [Figure 4] FIG. 4 shows a top view of the membrane of FIG. [Diagram 5] FIG. 5 shows a perspective view of the feed channel of the membrane of FIG. [Figure 5A] FIG. 5A shows a perspective longitudinal cutaway view of the feed channel of the membrane of FIG. [Figure 6] FIG. 6 shows a perspective view of the permeate channel of the membrane of FIG. [Figure 7] FIG. 7 shows a perspective view of a second embodiment of a membrane according to the invention. [Figure 7A] FIG. 7A shows a perspective longitudinal cutaway view of the membrane of FIG. [Figure 8] FIG. 8 shows a perspective view of the permeate channel of the membrane of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0396] A first embodiment of a membrane (100) according to the present invention is shown in Figures 1-6. The first embodiment of the membrane (100) according to the present invention has a membrane interface portion (102) that includes a feed flow channel (104), a permeate flow channel (106), and a membrane portion (108) that separates the two. The membrane interface portion (102) is created by a three-dimensional array of unit cells based on a TPMS gyroid lattice formed from repeating unit cells, and includes a network of interconnected feed flow channels (104) and permeate flow channels (106). The feed flow enters the membrane interface portion (102) at the proximal end A in the Z direction and passes through the feed flow channel (104) in a generally Z direction, while the retentate exits the membrane interface portion (102) at the distal end B.

[0397] The membrane (100) has a first unit cell layer (110) disposed toward a proximal end A of the membrane interface portion (102) and a second unit cell layer (112) disposed toward a distal end B. The unit cell layers extend along lateral directions X and Y substantially transverse to a general flow direction Z.

[0398] Each unit cell (114) of the unit cell layer has a feed flow channel (104), a permeate flow channel (106), and a membrane portion (108) having holes that allow fluid communication between the feed flow channel (104) and the permeate flow channel (106). The feed flow channels (104) and permeate flow channels (106) of adjacent unit cells are fluidly connected. The membrane interface portion (102) has a plurality of permeate outlets (116) disposed longitudinally around and along the peripheral side. The permeate flow channels (106) are connected to the openings of the permeate outlets (116) on the periphery of the membrane through which permeate can exit the membrane interface portion (102).

[0399] The lateral cell size C, D of the unit cells in the first unit cell layer (110) was 30 mm, and the lateral aspect ratio decreased from 1 to 0.7 from the first unit cell layer 110 at the proximal end to the second unit cell layer 112 at the distal end. The feed flow direction cell size E of the unit cells in the first unit cell layer (110) was 50 mm, and the feed flow direction aspect ratio gradually decreased from 1.7 to 0.7 from the first unit cell layer (110) at the proximal end to the second unit cell layer (112) at the distal end. The thickness of the unit cell walls also decreased from 2 mm in the first unit cell layer (110) at the proximal end to 1 mm in the second unit cell layer (112) at the distal end, as shown in FIG. 2.

[0400] Figures 5 and 5A show a network of interconnected feed flow channels (104) within the membrane, while Figure 6 shows a network of permeate flow channels (106).

[0401] A second embodiment of the membrane (200) according to the present invention is shown in Figures 7-8. The second embodiment membrane (200) is similar to the first embodiment membrane (100) except that the membrane interface portion (202) is formed from a three-dimensional array of unit cells (214) based on a TPMS diamond lattice (216) of repeating unit cells (214). EXAMPLES

[0402] A membrane according to a first embodiment of the present invention was produced using additive manufacturing as described below. Printer: Photocentric Liquid crystal Precision 1.5 Printing method: Digital Light Processing (DLP) Print layer height: 35 microns (35μm) ·Exposure time: 8 seconds Process: 1. A slurry was prepared by mixing the following: a. Ceramic powder: Almatis CL3000SG with D50 size of 2 microns (2 μm), 58.5% by weight b. Resin: Tethon 3D, 40% by weight c. Dispersant: Disperbyk-111>, 1% by weight d. Defoamer: Byk-1796, 0.25% by weight e. Photoinitiator: Omnirad 2022 by IGM resins, 0.25 wt% 2. To distribute the ceramic powder homogeneously in the resin, the mixture was ground in a mixer with ceramic grinding balls for 4 hours. 3. The slurry was poured into the printer tank and printing of the molded body was started. 4. The compacts were cleaned using an air compressor, washed in <isopropanol>, and then dried in an oven at 80° C. for 4 hours. 5. The compacts were then kept at 500°C in an oven for degreasing to burn off the volatile components. The heating rate was 0.3°C / min and the residence time, i.e. the duration during which the temperature did not change, was 1 hour. 6. The compact was then kept at 1500° C. in a sintering furnace. The heating rate was 0.3° C. / min and the dwell time, i.e. the duration during which the temperature did not change, was 1 hour. 7. The molded body was then cooled to room temperature at a rate of 1°C / min to obtain a porous ceramic membrane.

[0403] Computational Fluid Dynamics (CFD) simulations were performed for representative geometries of the membrane according to the first embodiment of the invention and compared with the results obtained for a conventional tubular membrane of the same volume, where the tube diameter is comparable to the feed channel width of the unit cells in the first layer while the distance between adjacent tubes is comparable to the permeate channel width. The following improvements were found for the membrane according to the invention with respect to the comparable tubular membrane: The membrane area with positive effect on permeate flux was over 30% higher. · The average shear stress on the membrane, which disrupts the concentration polarization on the membrane surface, was more than 150% higher. The average velocity in the feed channel in the distal region, which helps to increase turbulence and reduce the concentration polarization thickness, thus positively influencing the permeate flow rate, was 30% higher.

[0404] The definitions of mean shear stress and mean velocity are given below. The average wall shear stress is the area-weighted average wall shear stress over the surface of the membrane.

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[0405] Attention is directed to all articles and documents related to this application that are filed contemporaneously herewith or prior to this application and that are open to public inspection herewith, and the contents of all such articles and documents are incorporated herein by reference.

[0406] All of the features disclosed in this specification (including the accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations in which at least some of such features and / or steps are mutually exclusive.

[0407] Each feature disclosed in this specification (including the accompanying claims, abstract, and drawings), unless expressly stated otherwise, may be replaced by alternative features serving the same, equivalent, or similar purpose. Thus, unless expressly stated otherwise, each feature disclosed is merely an example of a generic series of equivalent or similar features.

[0408] The invention is not limited to the details of the embodiments described above, and extends to any novel or any novel combination of features disclosed in this specification (including the accompanying claims, abstract and drawings), or to any novel or any novel combination of method or process steps so disclosed.

Claims

1. It is a membrane, The supply liquid inlet and The retaining liquid outlet and Permeate outlet and A membrane interface portion including a plurality of supply liquid flow channels fluidly connected to the supply liquid inlet and the retaining liquid outlet, and a plurality of permeate liquid flow channels fluidly connected to the permeate liquid outlet, wherein the membrane interface portion is operable to enable fluid communication between the supply liquid flow channels and the permeate liquid flow channels through the membrane portion. A membrane comprising, wherein the membrane interface portion includes a decrease in dimensional characteristics from the supply fluid inlet toward the retaining fluid outlet, such that the membrane interface portion is operable to generate a higher cross-flow velocity toward the retaining fluid outlet in the membrane portion.

2. The film according to claim 1, which can be obtained by addition.

3. The film interface portion includes a first unit cell layer and a second unit cell layer, each unit cell layer extending substantially transversely with respect to the direction of the supply liquid flow, and each unit cell layer includes a plurality of unit cells. Each unit cell of the first and second layers includes a supply liquid flow channel portion, a permeate liquid flow channel portion, and a membrane portion that separates the supply liquid flow portion and the permeate liquid flow portion. The supply fluid flow channel portion and the permeate fluid flow channel portion of a unit cell are fluidly connected to the supply fluid flow channel portion and the permeate fluid flow channel portion of an adjacent unit cell. The plurality of unit cells in the first unit cell layer include an average of the same dimensional characteristics that is greater than the average dimensional characteristics of the plurality of unit cells in the second unit cell layer. The first unit cell layer is positioned closer to the supply fluid inlet than the second unit cell layer. The film according to claim 1.

4. The membrane according to claim 1, wherein the membrane interface portion includes a plurality of unit cell layers, and the plurality of unit cells in each subsequent unit cell layer extending from the proximal to the distal of the supply liquid inlet have decreasing average dimensional characteristics.

5. The film according to claim 1, wherein the plurality of unit cells in the first and / or second unit cell layer are in the form of a periodically repeating unit cell shape.

6. The film according to claim 1, wherein the first unit cell layer includes an average lateral aspect ratio higher than that of the second unit cell layer.

7. The film according to claim 1, wherein the first unit cell layer includes an average transverse aspect ratio of at least 0.2, for example, at least 0.

5.

8. The film according to claim 1, wherein the second unit cell layer includes an average transverse aspect ratio of at least 0.1, for example, at least 0.

4.

9. The film according to claim 1, wherein the second unit cell layer includes an average lateral aspect ratio up to 0.99, for example, up to 0.

8.

10. The membrane according to claim 1, wherein the first unit cell layer includes an average supply fluid flow direction aspect ratio higher than that of the second unit cell layer.

11. The membrane according to claim 1, wherein the first unit cell layer includes an average supply fluid flow direction aspect ratio of at least 0.

5.

12. The membrane according to claim 1, wherein the first unit cell layer includes an average supply fluid flow direction aspect ratio up to 10, for example, up to 4.

13. The membrane according to claim 1, wherein the second unit cell layer includes an average supply fluid flow direction aspect ratio of at least 0.1, for example, at least 0.

3.

14. The membrane according to claim 1, wherein the second unit cell layer includes an average supply fluid flow direction aspect ratio up to 5, for example, up to 3.

15. The film according to claim 1, wherein the second unit cell layer includes an average wall thickness smaller than that of the first unit cell layer.

16. The film according to claim 1, wherein the first unit cell layer has an average thickness ratio of at least 0.5, for example, at least 0.

8.

17. The film according to claim 1, wherein the second unit cell layer has an average thickness ratio of at least 0.1, for example, at least 0.

4.

18. The film according to claim 1, wherein the second unit cell layer has an average thickness ratio up to 0.99, for example, up to 0.

8.

19. The membrane according to claim 1, wherein the shape of the unit cell is a diamond structure, a cubic structure, a fluorite structure, an octet structure, a Kelvin cell structure, an isotruss structure, a hexagonal prism diamond structure, a truncated tube structure, a truncated octahedron structure, a Wier-Phelan structure, a body-centered cubic structure, and / or a face-centered cubic structure.

20. The film according to claim 1, wherein the periodically repeating unit cell shape is a triple-period minimum surface unit cell shape.

21. The film according to claim 1, wherein the periodically repeating unit cell shape is a triple-periodic minimum surface unit cell shape selected from a gyroid structure, a Schwartz P structure, a Schwartz D structure, a Schwartz CLP structure, a Schwartz H structure, a split P structure, a neobius structure, or a double gyroid.

22. The membrane according to claim 1, wherein the average width of the supply liquid flow channel of a unit cell is greater than the average width of the permeate liquid flow channel of a unit cell.

23. The membrane according to claim 1, wherein the membrane is a microfiltration membrane, an ultrafiltration membrane, and / or a nanofiltration membrane.

24. The membrane according to claim 1, wherein the modes in the microfiltration membrane or multi-model pore distribution include pore sizes of 0.01 μm to 10 μm, for example 0.05 μm to 5 μm, for example about 0.1 μm, and optionally a D50 pore size.

25. The membrane according to claim 1, wherein the microfiltration membrane, or the modes within the multi-model pore distribution, include a D10 pore size of at least 0.01 μm, for example, at least 0.05 μm, and / or a D90 pore size up to 10 μm, for example, up to 5 μm.

26. The ultrafiltration membrane, or the mode in the multi-model pore distribution thereof, is a membrane according to claim 1, wherein the pore size is 5 nm to 1 μm, for example 5 nm to 0.1 μm, for example about 0.01 μm, and optionally includes a D50 pore size.

27. The membrane according to claim 1, wherein the ultrafiltration membrane, or the modes within the multi-model pore distribution, include a D10 pore size of at least 5 nm and / or a D90 pore size up to 1 μm, for example, up to 0.1 μm, for example, up to 0.01 μm.

28. The nanofiltration membrane, or the mode in the multi-model pore distribution thereof, is a membrane according to claim 1, with pore sizes of 0.1 nm to 100 nm, for example 0.5 nm to 50 nm, for example 1 nm to 10 nm, for example 1 nm to 2 nm, or 2 nm to 10 nm, optionally including a D50 pore size.

29. The nanofiltration membrane, or the membrane according to claim 1, wherein the modes in the multi-model pore distribution include a D10 pore size of at least 0.1 nm, for example, at least 0.5 nm, for example, at least 1 nm, for example, at least 2 nm and / or a D90 pore size up to 100 nm, for example, up to 50 nm, for example, up to 10 nm, for example, up to 2 nm.

30. The film according to claim 1, wherein the film comprises an open porosity of at least 10%, for example, at least 20%, for example, at least 30%, for example, at least 40%, for example, at least 50%.

31. The film according to claim 1, wherein the film includes an open porosity of 10% to 60%, for example, 15% to 50%, or for example, 20% to 40%.

32. The membrane according to claim 1, comprising an open porosity of 10% to 40%, for example, 10% to 30%.

33. The membrane according to claim 1, wherein the membrane includes a closed void ratio of 0 to 90%, for example, 10 to 60%, or for example, 20 to 40%.

34. The film according to claim 1, comprising at least 40%, for example, at least 50%, or for example, at least 60% of the total.

35. The film according to claim 1, wherein the film has a tensile strength of 0.5 MPa or more, for example 1 MPa or more, for example 2 MPa or more, and optionally in the range of 2 MPa to 200 MPa.

36. The film according to claim 1, wherein the film is a ceramic film.

37. The aforementioned film is a. A step of providing a layer of ceramic powder on a powder bed, b. A step of selectively bonding a portion of the ceramic powder, c. A process of forming a 3D printed molded body by repeating steps (a) to (b), d. Optionally, a step of post-processing the 3D printed molded body to form the film. The film according to claim 1, which can be obtained by an addition manufacturing method including the following.

38. The film according to claim 1, which can be obtained by binder jet additive manufacturing.

39. A method for manufacturing a film according to any one of claims 1 to 38, a. A step of providing a layer of ceramic powder on a powder bed, b. A step of selectively bonding a portion of the ceramic powder, c. A process of forming a 3D printed molded body by repeating steps (a) to (b), d. Optionally, a step of post-processing the 3D printed molded body to form the film. Methods that include...

40. The method according to claim 39, wherein the ceramic powder comprises alumina, aluminum nitride, aluminum oxide, barium titanate, β-tricalcium phosphate, biological ceramics, bismuth, boron carbide, carbides, hydroxyapatite, iron oxide, magnesium silicate, nitrides, oxides, aluminum silicon, silica, silicon carbide, silicon dioxide, silicon nitride, titanate, titanium dioxide, yttrium carbonate, YSZ (yttria-stabilized zirconia), zinc oxide, zirconate, zirconia and zirconium, or mixtures thereof.

41. The method according to claim 39, wherein the ceramic powder comprises a volume average size of at least 1 nm, for example, at least 10 nm.

42. The method according to claim 39, wherein the ceramic powder includes a volume average size up to 100 μm, for example, up to 10 μm.

43. The method according to claim 39, wherein the ceramic powder includes a volume average size of 1 nm to 100 μm, for example, 10 nm to 10 μm or 1 nm to 10 μm.

44. The method according to claim 39, wherein the ceramic powder comprises a mixture of different ceramic powder compositions.

45. The method according to claim 39, wherein the ceramic powder comprises a coarse first ceramic powder fraction and a fine second ceramic powder fraction.

46. The ceramic powder has a compression density of at least 0.5 g / cm ３ , for example, at least 1 g / cm ３ , for example, at least 2 g / cm ３ , and / or up to 10 g / cm ３ , for example, up to 8 g / cm ３ , for example, up to 6 g / cm ３ , and / or a compression density of 0.5 to 10 g / cm ３ , for example, 1 to 8 g / cm ３ , for example, 2 to 6 g / cm ３ , The method according to claim 39, comprising a compression density of.

47. The ceramic powder must be at least 0.5 g / cm³ ３ For example, at least 1 g / cm³ ３ For example, at least 2 g / cm³ ３ The firing density, and / or 10 g / cm³ ３ Up to, for example, 8 g / cm³ ３ Up to, for example, 6 g / cm³ ３ Firing density up to and / or 0.5 to 10 g / cm³ ３ For example, 1-8 g / cm³ ３ For example, 2-6 g / cm³ ３ The method according to claim 39, which includes the firing density.

48. The film according to claim 37, wherein the additive manufacturing method comprises adding a binder composition to the ceramic powder, and the binder composition comprises a binder.

49. The film according to claim 48, wherein the binder comprises a metal binder, a ceramic binder, and / or a polymer binder.

50. The film according to claim 49, wherein the polymer binder comprises acrylate, methacrylate, acrylate polymer (e.g., polyacrylate), methacrylate polymer (e.g., poly(meth)acrylate), polyvinyl alcohol, polyethylene glycol, polyvinylpyrrolidone and / or carbohydrates (e.g., dextrin, maltodextrin, starch), or a combination thereof.

51. The film according to claim 49, wherein the polymer binder comprises polyacrylate, poly(meth)acrylate and / or polyethylene glycol.

52. The film according to claim 48, wherein the binder comprises phosphoric acid, colloidal silica, or a combination thereof.

53. The film according to claim 48, further comprising additive particles in the binder composition.

54. The film according to claim 48, wherein the binder composition further comprises additive particles selected from ceramic particles, metal oxide particles, and / or nonmetallic particles, for example, ceramic particles and / or metal oxide particles, and optionally the binder composition further comprises ceramic particles.

55. The film according to claim 53, wherein the additive particles include ceramic additive particles.

56. The film according to claim 55, wherein the ceramic additive particles include alumina, aluminum nitride, aluminum oxide, barium titanate, β-tricalcium phosphate, biological ceramics, bismuth, boron carbide, carbides, hydroxyapatite, iron oxide, magnesium silicate, nitrides, oxides, aluminum silicon, silica, silicon carbide, silicon dioxide, silicon nitride, titanate, titanium dioxide, yttrium carbonate, YSZ (yttria-stabilized zirconia), zinc oxide, zirconate, zirconia and / or zirconium, or mixtures thereof.

57. The membrane according to claim 55, wherein the additive microparticles include an average particle size of 0.1 μm to 20 μm, or 0.1 μm to 5 μm, optionally a D50 particle size, and / or a D10 particle size of at least 0.1 μm, and / or a D90 particle size up to 20 μm or up to 5 μm.

58. Nanoparticles and / or microparticles are formed in situ from nanoparticle and / or microparticle precursors during the addition process and / or post-processing steps. The ceramic film includes nanoparticles and / or microparticles, or their residues, that are formed in situ and placed within the pores of the film portion. The film according to claim 37.

59. The film according to claim 58, wherein the nanoparticles and / or microparticles can be obtained in situ from the nanoparticles and / or microparticle precursors during the production of the ceramic film.

60. The film according to claim 58, wherein the ceramic film contains up to 25% by weight, for example, up to 20% by weight, for example, 15% by weight, of nanoparticles and / or microparticles or their residues based on the total weight of the ceramic film, and / or the ceramic film contains at least 1% by weight, for example, at least 2% by weight, for example, at least 3% by weight, for example, at least 4% by weight, for example, at least 5% by weight, of nanoparticles and / or microparticles or their residues based on the total weight of the ceramic film.

61. The film according to claim 58, wherein the nanoparticles and / or microparticles are formed by heating the nanoparticles and / or microparticle precursor to at least 100°C, for example at least 300°C, for example at least 500°C, and / or optionally up to 1500°C, for example up to 1250°C, for example up to 800°C, and / or optionally between 100 and 1500°C, for example between 300 and 1250°C, for example between 500 and 800°C.

62. The film according to claim 58, wherein the nanoparticles and / or microparticles include metal-silica nanoparticles and / or microparticles; metal oxide nanoparticles and / or microparticles; mixed metal oxide nanoparticles and / or microparticles; non-metal oxide nanoparticles and / or microparticles; and / or metal nanoparticles and / or microparticles.

63. The film according to claim 58, wherein the nanoparticles and / or microparticles include metal oxide nanoparticles and / or microparticles; silicon oxide nanoparticles and / or microparticles; and / or metal-silicon oxide nanoparticles and / or microparticles.

64. The film according to claim 58, wherein the nanoparticles and / or microparticles include metal oxide nanoparticles and / or microparticles.

65. The film according to claim 62, wherein the metal-silica nanoparticles and / or microparticles include nickel-silica, silver-silica, platinum-silica, and / or iron-silica nanoparticles and / or microparticles.

66. The film according to claim 62, wherein the metal-silica nanoparticles and / or microparticles can be obtained from an in-situ reaction between a polysilazane and a metal complex.

67. The film according to claim 62, wherein the metal oxide nanoparticles and / or microparticles include aluminum oxide, magnesium oxide, titanium dioxide, magnesium oxide, copper oxide, and / or iron oxide nanoparticles and / or microparticles.

68. The film according to claim 58, wherein the nanoparticles and / or microparticles include mixed metal oxide nanoparticles and / or microparticles, for example, perovskite nanoparticles and / or microparticles.

69. The film according to claim 62, wherein the mixed metal oxide nanoparticles and / or microparticles can be obtained from a reaction between a transition metal salt, a rare earth metal salt, and an organic acid.

70. The film according to claim 58, wherein the nanoparticles and / or microparticles include nonmetallic oxide nanoparticles and / or microparticles, such as silica nanoparticles and / or microparticles.

71. The film according to claim 58, wherein the nanoparticles and / or microparticles include metal nanoparticles and / or microparticles, for example, silver nanoparticles and / or microparticles.

72. A water treatment module comprising a membrane according to any one of claims 1 to 38 and claims 48 to 71.

73. A separation portion for use in a device for reducing the ratio of divalent ions to monovalent ions in an aqueous solution from a raw aqueous solution having a higher ratio of divalent ions to monovalent ions, wherein the separation portion includes a membrane according to any one of claims 1 to 38 and claims 48 to 71.

74. A device for reducing the ratio of divalent ions to monovalent ions in an aqueous solution from a raw aqueous solution where the ratio of divalent ions to monovalent ions is higher, A pre-filtration section, optionally capable of receiving the raw aqueous solution and operating to produce a pre-filtered aqueous solution, A first separation section, operable to accept the optionally pre-filtered aqueous solution and to form an intermediate aqueous solution having a lower ratio of divalent ions to monovalent ions than the optionally pre-filtered aqueous solution, and / or A second separation unit that is operable to receive the intermediate aqueous solution and form a product aqueous solution having a lower ratio of divalent ions to monovalent ions than the intermediate solution. An apparatus comprising, wherein the pre-filtration portion, the first separation portion and / or the second separation portion, includes a separation portion comprising a membrane according to any one of claims 1 to 38 and claims 48 to 71.

75. The apparatus according to claim 74, wherein the first separation portion includes a membrane according to any one of claims 1 to 38 and claims 48 to 71, and the membrane is a nanofiltration membrane.

76. The apparatus according to claim 74, wherein the second separation portion comprises an ion exchange resin.

77. The apparatus according to claim 74, wherein the apparatus is for use in lithium extraction, for example, direct lithium extraction (DLE).

78. The apparatus according to claim 74, further comprising a further separation section that receives the raw product solution after the second separation section and is operable to select a specific type of monovalent ion.

79. The apparatus according to claim 78, wherein the further separation portion includes a (further) ion exchange separation portion.

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