Filter media for liquid filters

Abstract

Filtration media for liquid filters and liquid filters are provided that include a substrate, such as a porous membrane, and nanoparticles incorporated into the substrate. The nanoparticles may include nanoparticles, nanofibers, or microfibers having a size of at least one dimension of less than about 20 microns. The nanoparticles are bonded to the fibers in the substrate and dispersed "at a depth" within the substrate, which improves the performance characteristics of the material in many different applications. For example, nanoparticles increase the total surface area within the substrate, which may increase its filtration efficiency and allow for capture of submicron contaminants without significantly compromising other factors, such as bubble point or flux of the filter.

Description

Cross-reference to related applications

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 588,326, filed October 6, 2023, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0002] This specification generally relates to filter media for use in liquid filters, the filter media comprising a fibrous substrate, and nanoparticles, nanofibers and / or microfibers incorporated therein. Background Technology

[0003] Porous membranes are widely used in a variety of applications, depending on their properties, such as the materials used to prepare the membranes, their morphology, and the size of the pores. These membranes can be used as, for example, filter media, separation membranes, membrane adsorbers, membrane catalysts, or membrane bioreactors.

[0004] One specific application of porous membranes is liquid filtration. Liquid filtration is the process of removing solid particles, impurities, and contaminants suspended in a fluid flow. It typically involves the flow of process liquids (in the form of slurries and suspensions) through a permeable filter medium, and the blocking and retention of the captured solids.

[0005] There are two main types of liquid filtration: surface and depth filtration. The main difference between the filtration methods lies in the structure of their filter media. In surface filtration, particle sieving occurs on the surface of the filter media. There are gaps between the fibers of the filter media called pores. Particles with a diameter larger than the pore width are blocked on the upstream side of the filter media and form a filter cake. Particles with a diameter smaller than the pore width are allowed to pass through the filter media. At the start of the filtration process, the filter efficiency is approximately 50-60%. As the filter cake accumulates, the filtration efficiency increases to up to 100% because the filter cake also provides resistance to particle flow.

[0006] Surface filters are economical for liquid filtration. However, this type of filter has a lower particle holding capacity and is more prone to clogging. They also require more frequent replacement, but they can be reused after cleaning.

[0007] Depth filtration is used to trap particles throughout the entire depth of the filter media. Depth filters typically use thick, multi-layered filter media, which increases their density in the direction of flow. Larger particles are trapped on the surface of the filter where the media density is lowest, while the particle size gradually decreases throughout the filter's depth. The high pore volume of the filter provides a tortuous and difficult flow path for solids. The significant resistance it provides effectively prevents solid particles from binding into the filtrate.

[0008] Depth filters are typically used when process fluids contain a wide range of particle sizes. Depth filters can filter particles smaller than the average flow pore size, and they have a higher particle holding capacity, trapping large amounts of solids before they become clogged. They can remove gel-like particles from process fluids. Finally, they have a long service life and require less frequent replacement, but they are generally single-use products.

[0009] When determining the desired flow rate, key considerations are pore size and the required liquid flux. The membrane pore size is selected based on the expected performance of the final device. Porosity determines the membrane's functional properties, including flow rate and flux. For example, using membranes with smaller pore sizes generally increases the filter's efficiency in capturing contaminants. On the other hand, these smaller pore sizes typically result in lower flow rates and reduced flux compared to membranes with larger pore sizes.

[0010] Therefore, there is a need to provide improved filter media for liquid filters. In particular, there is a need to provide filter media with reduced pore size to improve the efficiency of contaminant capture, while essentially maintaining the flow rate or flux of the filter media. Summary of the Invention

[0011] The following is a brief overview of the claimed subject matter to provide a basic understanding of some aspects of it. This overview is not an exhaustive summary of the claimed subject matter. It is not intended to identify the key or decisive elements of the claimed subject matter or to define its scope. Its sole purpose is to present some ideas of the claimed subject matter in a concise form as a prelude to the more detailed description that follows.

[0012] Various embodiments provide filter media comprising a fiber-containing substrate and nanoparticles dispersed throughout at least a portion of the filter media. At least some of the nanoparticles are bonded to at least some of the fibers in the substrate. In some embodiments, the substrate comprises a porous membrane that can be configured as a filter media and is particularly suitable for liquid filters used in a variety of industries such as pulp and paper, food and beverage, steel production, industrial process fluids, wastewater, municipal, automotive, power generation, semiconductor manufacturing, mining / construction, oil / chemical refining, medical / pharmaceutical, and general manufacturing.

[0013] In various implementations, nanoparticles are thermally bonded to fibers. Fibers and nanoparticles can be thermally bonded, ultrasonically bonded, calendered, hot-air bonded, or a combination thereof. Thermal bonding may or may not involve applying pressure.

[0014] In various embodiments, the filter media comprises an adhesive or binder that binds fibers to nanoparticles. The adhesive may be sprayed onto the substrate, for example, before and / or after the nanoparticles are dispersed in the substrate. The adhesive inhibits the direct passage of nanoparticles through the membrane and, when the nanoparticles are bound to the adhesive, can increase the uniformity and permeability of the nanoparticles within the internal structure of the membrane. The adhesive is preferably an insoluble adhesive that is substantially insoluble in the liquid passing through the filter. Suitable insoluble adhesives include, but are not limited to, polyurethanes, epoxy resins, polyimides, starches, dextrins, latexes, acrylonitrile, polyvinyl alcohol, polyvinyl acetate, polyvinyl chloride, acrylics, ethylene-vinyl acetate, polyolefins, phenolic resins, urea-formaldehyde resins, polysulfides, cyanoacrylates, and combinations thereof.

[0015] The nanoparticles described herein typically have at least one dimension smaller than about 20 micrometers. In some embodiments, the nanoparticles have at least one dimension smaller than 1 micrometer (i.e., diameter, width, height, etc., depending on the cross-sectional shape of the fiber). In other embodiments, the nanoparticles comprise microfibers or nanofibers with at least one dimension having a dimension from about 1 micrometer to about 20 micrometers. For example, microfibers or nanofibers with a diameter or width less than 1 micrometer and a length greater than 1 micrometer are nanoparticles as used herein. In an exemplary embodiment, the microfiber has at least one dimension having a dimension of about 5 micrometers. The nanoparticles may have a continuous length, or they may have discrete lengths, such as 1 to 100,000 micrometers, preferably about 5 to 10,000 micrometers, or about 5 to about 1,000 micrometers, or about 100 to about 600 micrometers.

[0016] Nanoparticles can include any suitable material, such as glass, biosoluble glass, ceramic materials, acrylics, carbon, metals such as alumina, polymers such as polyethylene, high-density polyethylene (HDPE), low-density polyethylene (LDPE), nylon, polyethylene terephthalate, polypropylene (PP), polybutene (PBT), ethylene polyester (PET), polylactic acid (PLA), polyamide (PA), polyvinyl chloride (PVC), polyolefins, polyacetals, polyesters, cellulose ethers, polyalkylene sulfides, poly(aryloxides), polysulfones, modified polysulfone polymers, and polyvinyl alcohol, polyamides, polystyrene, polyacrylonitrile, polyvinylidene chloride, polymethyl methacrylate, polyvinylidene fluoride, and any combination thereof.

[0017] In the embodiments, the nanoparticles include microfibers selected from the group including, but not limited to, metal fibers, carbon fibers, polypropylene (PP), nylon fibers, polybutene (PBT), ethylene polyester (PET), polylactic acid (PLA), polyamide (PA), glass, biosoluble glass, ceramic materials, acrylics, polyethylene, high-density polyethylene (HDPE), low-density polyethylene (LDPE), and combinations thereof.

[0018] In one embodiment, the fibrous substrate comprises a porous membrane. In an exemplary embodiment, the average flow pore size of the porous membrane is less than about 10 micrometers. The nanoparticles reduce the average flow pore size of the membrane while substantially maintaining the liquid flow rate through the membrane.

[0019] In the embodiments, the average flow pore size of the membrane is less than 5 micrometers, preferably less than 4 micrometers, more preferably less than 3 micrometers, and more preferably less than about 1 micrometer.

[0020] The fibers in the substrate can be man-made or natural fibers. Suitable materials for substrate fibers include, but are not limited to, metal fibers, carbon fibers, polypropylene (PP), polyester (PET), PEN polyester, PCT polyester, polybutene (PBT), ethylene polyester (PET), polylactic acid (PLA), polyamide (PA), copolyamide, polyethylene, high-density polyethylene (HDPE), low-density polyethylene (LDPE), cross-linked polyethylene, polycarbonate, polyacrylate, polyacrylonitrile, polyfuran, polystyrene, styrene-maleic anhydride, polymethylpentene, cyclic olefin copolymers or fluorinated polymers, polytetrafluoroethylene, perfluoroethylene and hexafluoropropylene or copolymers with PVDF (such as P(VDF- TrFE) or terpolymers (such as P(VDF-TrFE-CFE)), propylene, polyimide, polyetherketone, cellulose esters, nylon and polyamide, polymethacrylic acid, poly(methyl methacrylate), polyoxymethylene, polysulfonate, acrylics, styrene acrylics, pre-oxidized acrylics, fluorinated acrylics, vinyl acetate, vinyl acrylics, ethylene vinyl acetate, styrene-butadiene, ethylene / vinyl chloride, vinyl acetate copolymers, latex, polyester copolymers, carboxylated styrene acrylics or vinyl acetate, epoxy resins, acrylic multipolymers, phenolic resins, polyurethanes, cellulose, styrene or any combination thereof.

[0021] In some embodiments, the fibers in the substrate may comprise polyolefins, polyesters, polyethylene (PE), polypropylene (PP), blends of PP and PE, PBT, PET, CoPET, PLA, PA, PHB, PVOH, PVA polyamide, and combinations thereof. In exemplary embodiments, the substrate comprises bicomponent fibers, such as CoPET / PET or HDPE / PET.

[0022] Fibers can be manufactured and formed into a substrate in any suitable manner, including but not limited to meltblown, spunbond or hydroentangled, gradient spunbond, thermal bonding, bonded carding, air-laid, wet-laid, cellulose wet-laid, glass wet-laid, synthetic wet-laid, composite wet-laid, co-forming, needle punching, stitch braiding, hydraulic entanglement, hydroentangled entanglement, ultrasonic bonding, etc. In all the above examples, the fibers can be hydroentangled or hydraulically entangled. In one exemplary embodiment, the web is formed by dry-laid (carding), wet-laid, or bicomponent spunbond. In a particularly preferred embodiment, the substrate comprises wet-laid bicomponent fibers, such as CoPET / PET or HDPE / PET.

[0023] The fibers in the substrate can have various cross-sectional shapes, including but not limited to circular, bean-shaped, dogbone-shaped, trefoil-shaped, barbell-shaped, bowtie-shaped, star-shaped, and Y-shaped. Each section contains a different range of denier fibers. The fibers can include bio-component fibers, which comprise two or more different fibers bonded together. The fibers can contain the same or different materials. The fibers can include bio-component fibers having a core and a sheath. The core can be concentric or non-concentric relative to the longitudinal axis of the sheath.

[0024] In some embodiments, the nanoparticles are isolated within a fluid and dispersed through a first surface of the substrate. The fluid may be a gaseous medium, such as air, helium, nitrogen, oxygen, carbon dioxide, etc. The nanoparticles may be dispersed from the gaseous medium via an airflow, aerosol, vaporizer, spray, or other suitable delivery mechanism.

[0025] In one embodiment, the substrate is advanced from upstream to downstream, and the nanofiber assembly is introduced into a fluid medium. Within the fluid medium, the nanofiber assembly is transformed into nanoparticles, which are then dispersed into the substrate between the upstream and downstream ends to form a filter medium.

[0026] In some embodiments, the nanoparticles are dispersed "at a certain depth" within the substrate or porous membrane. As used herein, the term "at a certain depth" means that the nanoparticles are dispersed across a first surface of the membrane such that at least some nanoparticles are disposed between the first and second opposing surfaces within the internal structure of the membrane. In some embodiments, the nanoparticles are substantially dispersed throughout the entire membrane from the first surface to the opposing second surface. In other embodiments, the nanoparticles are dispersed within a portion of the membrane at a location between the first and second surfaces.

[0027] Nanoparticles can be disposed on the first and / or second opposing surfaces of the membrane such that the areal density of the nanoparticles decreases from the first surface to the second surface, or the areal density of nanoparticles disposed on one or both surfaces is higher than that on the middle portion of the membrane. In some embodiments, the density of nanoparticles located on the first surface differs from the density of nanoparticles dispersed in the central portion or midpoint between the two surfaces of the substrate by less than 50%. In some embodiments, this difference is less than 25%, preferably less than 10%. In some embodiments, the amount or number of individual nanoparticles dispersed in the central portion of the membrane is at least about 50%, preferably at least about 75%, and more preferably at least about 90% of the amount of individual nanoparticles dispersed on or near the first surface.

[0028] In some embodiments, nanoparticles may be added to the film from both the first and second surfaces. In these embodiments, the areal density, or "addition amount," at the first and second surfaces may be substantially equal to each other, or they may vary depending on the application. In these embodiments, the areal density, or "addition amount," at the intermediate substrate surface is lower than that at the outer surface surface. For example, the areal density at the intermediate substrate surface may be about 75% of the areal density at the outer surface surface, or it may be about 50%, 40%, or 25%.

[0029] In another aspect, the liquid filter includes: a housing having an inlet for receiving liquid and an outlet for discharging liquid; and a fiber substrate disposed within the housing between the inlet and the outlet. The fiber substrate includes: a first surface, an opposing second surface, and a plurality of nanoparticles disposed within the fiber substrate between at least the first and second surfaces.

[0030] In this implementation, the liquid filter is a depth filter and / or an accretion filter. The housing may include any suitable housing for a liquid filter, such as a cartridge, bag, centrifuge, etc.

[0031] In one embodiment, the fiber substrate includes a porous membrane comprising fibers and having an average flow pore size of less than about 10 micrometers. In another embodiment, the average flow pore size of the membrane is less than 5 micrometers, preferably less than 4 micrometers, more preferably about 3 micrometers, and most preferably less than 1 micrometer.

[0032] The filter has a bubble point of less than about 20 in / h20, or less than about 15 in / h20. The bubble point is defined herein as the amount of force required to make the liquid pass through the substrate (i.e., the higher the value, the more difficult it is to make the liquid pass through the substrate).

[0033] In the implementation scheme, the liquid filter may include, for example, an air inlet filter, a plate filter, a filter press, a drum filter, a clean-in-place (CIP) filter, a bag filter, or a cartridge filter. The filter cartridge may include square end cap cartridges, V-shaped compact filters, flat unit filters, pleated cartridges, conical cartridges, spunbond cartridges, activated carbon cartridges, reverse osmosis membrane cartridges, alkaline cartridges, ultraviolet cartridges, synthetic filter media, wound cartridges, etc.

[0034] In the implementation plan, liquid filters include fuel filters, such as diesel fuel filters, hydrocarbon fuel filters, gasoline fuel filters, canister fuel filters, inline fuel filters, in-tank fuel filters, cartridge fuel filters, carburetor inlet filters, pump outlet fuel filters, swirl fuel filters, etc.

[0035] In the implementation scheme, the liquid filter includes semiconductor processing filters, such as microfiltration filters, chemical filters, CMP filters, lithography filters, process gas filters, chemical mechanical polishing filters, wastewater filters, wet etching and cleaning filters, PFOA filters, etc.

[0036] In the implementation scheme, the liquid filter includes municipal filters, such as wastewater filters used in water treatment plants. Municipal filters may include, but are not limited to, screen filters, slow sand filters, disc filters, fast sand filters, membrane filters, bag filters, reverse osmosis filters, etc.

[0037] In the implementation scheme, liquid filters include pipeline filters, such as turbine air filters, particulate filters, clay processor filters, amine filters, two-stage coalescer-separator filters, coarse filters, natural gas pipeline filters, Y-type filters, T-type filters, basket filters, magnetic filters, backwash filters, etc.

[0038] In the implementation scheme, liquid filters include food or beverage filters, such as filters configured for making juice and soft drinks, water filters for tanks and containers, basket centrifuges for producing salt, disc centrifuges for separating cream from milk, water purification membranes, rotary vacuum drum filters for separating syrup from filter mud, hydrocyclones for purifying starch, disc or tubular centrifuges for refining vegetable seed oils, decanter centrifuges or filter presses for dehydrating separated grains in, for example, breweries or breweries.

[0039] In the implementation scheme, the liquid filter can be configured for use in the pharmaceutical industry for plasma fractionation, special enzymes, vitamins, diagnostics, botanical drugs, red biotechnology, white biotechnology, and may include filters such as magnetic filters, bag filters, self-cleaning filters, reverse osmosis membranes, ultrafiltration membranes, and nanofiltration membranes.

[0040] In the implementation scheme, the liquid filter can be configured as an industrial filter, such as an industrial filter for chemical, paint manufacturing, organic solvent, ink, oil and kerosene industry water treatment, cosmetic, wine and pharmaceutical industries, including pleated cartridges, melt-blown cartridges, wound cartridges, membrane cartridges, carbon cartridges and other specialized cartridges.

[0041] In the implementation scheme, the liquid filter includes hydraulic filters, such as oil filters, swirl filters, return line filters, duplex filters, offline or online filters, box filters, etc.

[0042] In the implementation scheme, the liquid filter includes a metal filter, such as stainless steel, copper, activated carbon, aluminum, etc.

[0043] In the implementation, the liquid filter includes a battery separator, such as an alkaline battery separator, including but not limited to zinc-manganese dioxide (Zn / MnO2), nickel-cadmium (Ni-Cd), and nickel-metal hydride (Ni-H2) batteries.

[0044] The description of the desired objectives fulfilled by the various embodiments of this specification is not intended to imply or suggest that any one or all of these objectives are essential features, either alone or collectively, present in the most generalized embodiment of this specification or in any more specific embodiment. Brief description of the attached figures

[0045] Figure 1 It is a side view of a filter medium containing nanoparticles dispersed in a portion of the material. Figure 2 It is a side view of a filter medium containing nanoparticles dispersed throughout the material; Figure 3 It is a side view of a filter medium having nanoparticles dispersed in the material in a gradient. Figure 4 The dual-layer filter media is shown; Figures 5A-5C Bio-component fibers incorporated into a porous membrane are shown; Figure 6 A liquid cartridge filter is shown; Figure 7 A liquid bag filter is shown; Figure 8 A metal filter including a perforated plate is shown; Figure 9 The synthetic filter media is shown; Figure 10 A pleated filter cartridge is shown; Figure 11 A spunbond filter cartridge is shown; Figure 12A wound filter cartridge is shown; Figure 13 A membrane filter cartridge is shown; Figure 14 This is a partial cross-sectional view of the liquid filter housing; Figure 15 A multi-bag filter system is shown; Figure 16 A rotary drum filter is shown; Figure 17 A filter press is shown; Figure 18A This is a partial cross-sectional view of the fuel filter; Figure 18B This is a partial cross-sectional view of a fuel filter used in a vehicle; Figure 19 A filter for removing large slurry particles in a semiconductor manufacturing facility is shown. Figure 20 A water filtration device for semiconductor manufacturing equipment is shown; Figure 21 A pipe filter is shown; Figure 22 A system for manufacturing filter media is illustrated schematically; Figure 23 A system for decomposing and / or isolating individual nanoparticles and dispersing nanoparticles onto a substrate is schematically illustrated. Figure 24 It shows Figure 23 The system's injectors; Figure 25 It shows Figure 23 The system's reactor; Figure 26 Another embodiment of a system for decomposing and / or isolating individual nanoparticles and dispersing nanoparticles onto a substrate is shown; Figure 27 A system for manufacturing dual-layer filter media is shown; Figure 28 This is a schematic diagram of a feeding system used to deliver nanoparticles to one of the aforementioned filter media manufacturing systems; Figure 29 yes Figure 28 A more detailed view of the feeding system; Figure 30 It is used to receive clusters of nanoparticles and introduce nanoparticles into... Figure 28 and Figure 29 A partial cross-sectional schematic diagram of the bulk material hopper in the feeding system; Figure 31 yes Figure 30 Another schematic diagram of the bulk silo; Figure 32 The rotor inside the bulk silo is shown; Figure 33 This is an enlarged view of the lower opening of the bulk silo, showing a portion of the lift, which is configured to convey nanoparticles out of the bulk silo and lift them through the feeding system; Figure 34 A portion of the elevator is shown; Figure 35 Another part of the elevator is shown; Figure 36 It shows Figure 35 The nanoparticle clusters within that section of the elevator shown; Figure 37 A receiving container for conveying nanoparticles from an elevator to a feed hopper is shown. Figure 38 This is a schematic diagram of the feed hopper; Figure 39 This is another schematic diagram of the feed hopper; Figure 40 The interior of the feed hopper is shown; Figure 41 This is an enlarged view of the interior of the feed hopper, showing the screw conveyor used to transport nanoparticles out of the feed hopper; Figure 42 Another receiving container is shown for conveying nanoparticles from the feed hopper to the fiber manufacturing system; Figure 43 A fine-tuning flow control device for conveying nanoparticles into fiber manufacturing equipment is shown; and Figure 44 A vibrating element is shown for vibrating a receiving container to transport nanoparticles through it. Detailed Implementation

[0046] This specification and accompanying drawings illustrate exemplary embodiments and should not be considered limiting. The scope of this specification is defined by the claims (including equivalents). Various mechanical, compositional, structural, and operational changes may be made without departing from the scope of this specification and the claims (including equivalents). In some cases, well-known structures and techniques have not been shown or described in detail to avoid obscuring the description. Identical numbers in two or more drawings represent the same or similar elements. Furthermore, whenever feasible, elements and related aspects described in detail with reference to one embodiment may be included in other embodiments where they are not specifically shown or described. For example, if an element is described in detail with reference to one embodiment but not with reference to a second embodiment, that element may still be included in the second embodiment. Moreover, the descriptions herein are for illustrative purposes only and do not necessarily reflect the actual shape, size, or dimensions of the system or illustrated components.

[0047] It should be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the,” and any singular use of any word, include plural referents unless clearly and explicitly defined as a single referent. As used herein, the term “comprising” and its grammatical variations are intended to be non-limiting, such that the description of items in the list does not exclude other similar items that may be substituted for or added to the listed items.

[0048] Unless otherwise stated, all quantitative values ​​are approximate, whether or not words such as "about" or "approximately" are used. The materials, methods, and embodiments described herein are exemplary only and are not intended to be limiting.

[0049] Various embodiments provide a filter medium comprising a fiber-containing substrate and nanoparticles dispersed throughout at least a portion of the filter medium. In some embodiments, the substrate comprises a porous membrane that can be configured as a filter medium and is particularly suitable for liquid filters used in a variety of industries such as pulp and paper, food and beverage, steel production, industrial process fluids, wastewater, municipal, automotive, power generation, semiconductor manufacturing, mining / construction, oil / chemical refining, medical / pharmaceutical, and general manufacturing. The filter media provided herein are particularly suitable for depth filters and / or accretion filters. When used in accretion filters, the liquid filter may include a filter aid. Suitable filter aids include, but are not limited to, diatomaceous earth, perlite, cellulose, fly ash, carbon, silica, Solkafloc, and combinations thereof.

[0050] For example, various implementation schemes include fuel filters, such as diesel fuel filters, hydrocarbon fuel filters, gasoline fuel filters, canister fuel filters, online fuel filters, in-tank fuel filters, cartridge fuel filters, carburetor inlet filters, pump outlet fuel filters, swirl fuel filters, etc.

[0051] For example, various implementation schemes include gas turbine and compressor inlet filters, plate filters, filter presses, drum filters, water treatment plant filters, biological filters, membrane bioreactor membranes, hydrocarbon filters, diesel filters, fuel filters, hydraulic fluid filters, food and beverage filters, semiconductor filters, microfiltration membranes, downstream membrane filtration, pharmaceutical and medical filters, wastewater filters, industrial process and / or municipal filters, pipeline gas turbine and compressor inlet filters, plate filters, cartridge filters, bag filters, clean-in-place (CIP) filters, battery separators, etc.

[0052] For example, various implementations include semiconductor processing filters that filter nanoscale particles and harmful contaminants during logic and chip manufacturing, including microfiltration filters with hydrophobic or hydrophilic membranes, chemical filters, CMP filters, lithography filters, process gas filters and purifiers, chemical mechanical polishing filters, electrolyte plating filters, wastewater filters, wet etching and cleaning filters, PFOA filters, etc.

[0053] For example, various implementations include filters for the food or beverage industry to remove solid and / or liquid contaminants, including filters for making juices and soft drinks, water filters for tanks and containers, basket centrifuges for salt production, disc centrifuges for separating cream from milk, water purification membranes, rotary vacuum drum filters for separating syrup from filter mud, hydrocyclones for purifying starch, disc or tubular centrifuges for refining vegetable seed oils, and decanting centrifuges or filter presses for dehydrating separated grains in, for example, breweries or breweries.

[0054] For example, various implementation schemes include filters for the pharmaceutical industry, for plasma fractionation, special enzymes, vitamins, diagnostics, botanical drugs, red biotechnology, white biotechnology, and may include filters such as magnetic filters, bag filters, self-cleaning filters, reverse osmosis membranes, ultrafiltration membranes, and nanofiltration membranes.

[0055] For example, in various implementations, industrial filters are provided for removing solid and / or liquid contaminants from liquid process streams in refining, petrochemical, chemical, oil and gas, paint manufacturing, organic solvents, inks, petroleum and kerosene industrial water treatment, cosmetics, wine, and pharmaceutical industries. These filters include pleated cartridges, melt-blown cartridges, wound cartridges, membrane cartridges, carbon cartridges, wound fiber deep liquid cartridges, stainless steel cartridges, pleated series liquid cartridges, and other specialized cartridges. The ratings of these filters can range from less than about 1 micrometer to about 100 micrometers.

[0056] For example, hydraulic filters are provided for removing particulate matter from hydraulic fluids. Hydraulic filters can be full-flow or split-flow types, and can include, but are not limited to, oil filters, swirl filters, return-line filters, duplex filters, offline and online filters, and box filters.

[0057] For example, various implementation schemes include municipal filters, such as filters used in water treatment plants. These filters may include, but are not limited to, screen filters, slow sand filters, disc filters, fast sand filters, membrane filters, bag filters, reverse osmosis filters, etc.

[0058] For example, various implementation schemes include gas pipeline filters, such as turbine air filters, particulate filters, clay processor filters, amine filters, two-stage coalescer-separator filters, coarse filters, natural gas pipeline filters, Y-type filters, T-type filters, basket filters, magnetic filters, backwash filters, etc.

[0059] For example, various implementation schemes include power generation filters, such as hydroelectric power generation filters, solar power generation filters, nuclear power generation filters, water filter cartridges, sintered metal filters, wedge wire filters, demister pad filters, etc.

[0060] For example, various embodiments include battery separators that serve as mechanical barriers between electrodes to prevent short circuits while allowing ion transport through the electrolyte in the pores. For example, various embodiments include alkaline battery separators, including but not limited to zinc-manganese dioxide (Zn / MnO2), nickel-cadmium (Ni-Cd), and nickel-hydrogen (Ni-H2) batteries. Battery separators may comprise a substrate containing a blend of polyvinyl alcohol (PVA) fibers and cellulose or cellulose derivatives (e.g., rayon or lyocell).

[0061] Various embodiments also provide systems, apparatus, and methods for producing porous membranes, filter media, and products containing porous membranes or filter media (e.g., liquid filters). Such systems and methods may include: isolating individual nanoparticles in a gaseous medium (e.g., air, helium, nitrogen, oxygen, carbon dioxide, etc.) (instead of a liquid) and dispersing the nanoparticles into the porous membrane via an airflow, aerosol, vaporizer, spray, or other suitable delivery mechanism.

[0062] While the following description is primarily directed to filter media and liquid filters, it should be understood that the apparatus and methods disclosed herein can be readily adapted to a wide range of other applications. For example, the filter media disclosed herein can be used in household cleaning products, roofing and flooring products, automotive interiors and roof linings, reusable bags, wall coverings, filtration devices, insulation materials, and more. Furthermore, the individual nanoparticles isolated and generated in the methods described herein can be used in a variety of coatings, composites, and / or additives, such as polymers, food packaging, flame retardants, fuel cells, battery packs, capacitors, nanoceramics, lamps, materials manufacturing, production methods, reinforcements for composites, cement, and other materials, medical diagnostic applications, medical therapeutic devices or therapies, tissue engineering (e.g., scaffolds for bone or tissue repair), drinking water, industrial process fluids, food and beverage products, pharmaceuticals and biologics, tissue imaging, medical therapy delivery, environmental applications (e.g., biodegradable compounds), and more.

[0063] The nanoparticles described herein typically have at least one dimension smaller than about 20 micrometers. In some embodiments, at least one dimension of the nanoparticle is smaller than 1 micrometer (i.e., diameter, width, height, etc., depending on the cross-sectional shape of the fiber). In various embodiments, each individual nanoparticle can be a small particle with a size of about 1 to about 1000 nanometers, preferably about 1 to about 650 nanometers. In the number size distribution, at least half of the particles can be measured to be 100 nanometers or less. Most nanoparticles typically consist of only a few hundred atoms. When the size of nanoparticles approaches the atomic scale, the material properties change. This is due to the increased surface area to volume ratio, resulting in the surface atoms of the material dominating the material's properties. Because of the extremely small size of nanoparticles, their surface area to volume ratio is very large when compared to bulk materials (e.g., powders, plates, sheets, or even larger fibers). This characteristic gives nanoparticles unexpected optical, physical, and chemical properties, as they are small enough to confine their electrons and produce quantum effects.

[0064] In other embodiments, the nanoparticles comprise microfibers or nanofibers with at least one dimension having a size of about 1 micrometer to about 20 micrometers. For example, microfibers or nanofibers with a diameter or width less than 1 micrometer and a length greater than 1 micrometer are nanoparticles as used herein. In an exemplary embodiment, the microfiber has at least one dimension having a size of about 5 micrometers. The nanoparticles may have a continuous length, or the nanoparticles may have discrete lengths, such as 1 to 100,000 micrometers, preferably about 5 to 10,000 micrometers, or about 5 to about 1,000 micrometers, or about 100 to about 600 micrometers.

[0065] In some embodiments, the nanoparticles are dispersed within the substrate “at a certain depth.” As used herein, the term “at a certain depth” means that the nanoparticles are dispersed across a first surface of the fiber layer, such that at least some of the nanoparticles are arranged between the first and second opposing surfaces within the internal structure of the filter medium. In some embodiments, the nanoparticles are dispersed across substantially the entire medium from the first surface to the opposing second surface. In other embodiments, the nanoparticles are dispersed within a portion of the medium at a location between the first and second surfaces.

[0066] In some implementations, the nanoparticles are spatially distributed in a three-dimensional manner relative to the supporting fibers, which increases the fiber surface area and microvolume within the filter media. This three-dimensional distribution also prevents complete clogging of specific sections of the filter media, which is particularly useful in filter media because it allows fluids (e.g., air and other gases) to pass through the filter, thereby reducing the overall liquid flux across the filter.

[0067] In other embodiments, the nanoparticles are arranged across the thickness of the fiber layer in a density gradient, such that the density of nanoparticles disposed near a surface is higher than that of the opposite surface, or the density of nanoparticles disposed on the surface is higher compared to the middle portion of the fiber layer. The density gradient can be substantially linear, it can decrease in the form of a series of discrete steps, or the gradient can be random (i.e., the decrease in density is typically not linear or stepwise). Such a density gradient provides many advantageous characteristics for certain applications (e.g., filters) (discussed below).

[0068] Nanoparticles or microfibers are bonded to fibers in a substrate, or at least some nanoparticles are bonded to at least some fibers. In some embodiments, the substrate or filter medium may contain an adhesive or bonding material, such as an adhesive or binder, to facilitate adhesion between fibers and / or retention of nanoparticles in the membrane, such that nanoparticles can adhere to the fibers or otherwise be retained by the fibers within the substrate to form a stable matrix. The adhesive or bonding material is preferably present in a relatively small amount to bond individual nanoparticles to the fibers throughout the substrate.

[0069] Adhesives can contain a variety of insoluble adhesives. Suitable insoluble adhesives include, but are not limited to, polyurethane, epoxy resins, polyimide, starch, dextrin, latex, acrylonitrile, polyvinyl alcohol, polyvinyl acetate, polyvinyl chloride, acrylics, ethylene-vinyl acetate, polyolefins, phenolic resins, urea-formaldehyde resins, polysulfides, and cyanoacrylates. Adhesives can be solutions, emulsions, suspensions, hot melts, curables, pure substances, and / or combinations thereof.

[0070] In some embodiments, an adhesive resin is used, and the adhesive resin can be cross-linked after the adhesive is applied to the substrate. Adhesion (water resistance / solvent resistance) can be promoted by self-cross-linking during solvent evaporation in the adhesive formulation or by thermal activation during the drying process. For some adhesives, cross-linking can be achieved by electromagnetic radiation of high-energy wavelengths (including but not limited to RF, UV, or electron beams). The amount of adhesive can be controlled by adjusting the nozzle size of the spray gun 140 or by controlling the flow rate of the adhesive composition. The adhesive can be applied using a nozzle, dip coating, or other methods.

[0071] In some embodiments, the adhesive or bonding material may include a surfactant to reduce the surface or interfacial tension of the adhesive, thereby increasing its dispersibility and wetting properties, and making it easier for the adhesive to penetrate into a film to a certain depth. Suitable surfactants for use with the adhesives disclosed herein include nonionic, anionic, cationic, and amphoteric surfactants, such as sodium stearate, 4-(5-dodecyl)benzenesulfonate, sodium dodecylbenzenesulfonate wetting agents, docusate (sodium dioctyl sulfonate), alkyl ether phosphates, benzalkonium chloride (BAC), perfluorooctane sulfonate (PFOS), etc.

[0072] In some embodiments, the membrane comprises its own adhesive composition. In these embodiments, adhesives or bonding materials may or may not be added to the membrane. In one such embodiment, the substrate comprises bio-component fibers, wherein one of the components comprises an outer sheath at least partially surrounding an inner core (see...). Figure 5A and 5C ).

[0073] The sheath may contain a material that bonds with the nanoparticles. For example, the sheath may contain a material that becomes viscous and / or fluid upon heating and / or drying. During the heating / drying step (discussed below), the sheath portion of the fiber is heated to its melting point until it becomes viscous and / or fluid, thereby bonding the nanoparticles to the substrate. In a preferred embodiment, bonding and drying are performed simultaneously.

[0074] Nanoparticles can include any suitable material, such as glass, biosoluble glass, ceramic materials, acrylics, carbon, metals such as alumina, polymers such as polyethylene, high-density polyethylene (HDPE), low-density polyethylene (LDPE), nylon, polyethylene terephthalate, polypropylene (PP), polybutene (PBT), ethylene polyester (PET), polylactic acid (PLA), polyamide (PA), polyvinyl chloride (PVC), polyolefins, polyacetals, polyesters, cellulose ethers, polyalkylene sulfides, poly(aryloxides), polysulfones, modified polysulfone polymers, and polyvinyl alcohol, polyamides, polystyrene, polyacrylonitrile, polyvinylidene chloride, polymethyl methacrylate, polyvinylidene fluoride, and any combination thereof.

[0075] In some embodiments, the nanoparticles can be fabricated into bicomponent segmented disc-shaped and island-shaped forms. The filaments are then stretched to obtain submicron filaments. The continuous filament nanoparticles are cut to the desired length (preferably about 100 to about 10,000 micrometers).

[0076] In some embodiments, the nanoparticles are absorbents and adsorbents. In some embodiments, the nanoparticles are activated carbon fibers or activated carbon powder. In some embodiments, the nanoparticles are catalytic particles or catalytic fibers. In some embodiments, nanoparticles can be obtained by feeding submicron fibers into a pulverizer, crusher, or trimmer, wherein bonded fibers enter and are chopped into short fibers. For example, submicron nanoparticles can be obtained by feeding low-weight bio-component meltblown or nano-meltblown fabric into a pulverizer.

[0077] In some implementations, different nanoparticles can be mixed. For example, nanoparticles and nanobeads can be mixed. Two different nanoparticles with different melting points can also be mixed, allowing the lower-melting-point nanoparticles to act as a binder for the higher-melting-point nanoparticles. Nanoparticles with different diameters and lengths can also be mixed.

[0078] In some embodiments, the nanoparticles are selected from environmentally sustainable raw materials. Nanoparticles may include biosoluble glass nanoparticles, biodegradable nanoparticles, compostable nanoparticles, or recyclable compositions.

[0079] Different types of nanoparticles can be combined. Some nanoparticles can be functional nanoparticles. For example, functional nanoparticles may include activated carbon and / or antimicrobial materials deposited on and / or attached to fibers in the filter medium. This can improve the gas absorption efficiency and bactericidal efficacy of the fibers. In addition, fiber products with microfibers deposited with glass and carbon nanoparticles can provide filtration and deodorization functions as filter media.

[0080] The substrate can include a structure of individual fibers or threads interwoven, interlocked, or bonded together. For example, nonwoven fabrics can include sheet or web structures bonded together by mechanical, thermal, or chemical entanglement of fibers or filaments (and by perforated membranes). They can be substantially flat, porous sheets made directly from individual fibers or molten plastic or plastic film. Examples of suitable nonwoven materials include, but are not limited to, fibers, layers, or webs formed by meltblowing, spunbonding or hydroentangling, gradient spunbonding, thermal bonding, bonded carding, air-laid, wet-laid, cellulose wet-laid, glass wet-laid, synthetic wet-laid, composite wet-laid, co-forming, needle punching, stitch braiding, hydraulic entanglement, hydroentangled entanglement, ultrasonic bonding, etc. In all the above examples, the fibers can be hydroentangled or hydraulically entangled.

[0081] In one exemplary embodiment, the web is formed by dry web forming (carding), wet web forming, or bicomponent spunbonding. In a particularly preferred embodiment, the substrate comprises wet-laid bicomponent fibers, such as CoPET / PET or HDPE / PET.

[0082] In various implementations, the substrate may comprise knitted and / or woven materials. Knitted materials may include any knitted pattern suitable for the desired application. Suitable knitted materials for filter applications include weft knitting, warp knitting, knitted mesh, compressed knitted mesh, etc. Suitable woven materials for filter applications include textile filter media, such as monofilament fabrics, multifilament fabrics, nylon mesh, polyester mesh, polypropylene mesh, etc. Woven textiles can be used, for example, for mesh filter press filter cloths, woven filter pads and other die-cut parts, centrifuge filter bags, liquid filter bags, dust collector filter bags, bed dryer filter bags, rotary drum filters, filter belts, leaf filters, rolled media, etc.

[0083] In various embodiments, the average flow pore size of the filter medium is preferably less than about 10 micrometers. In some embodiments, the average flow pore size of the filter medium is less than 5 micrometers, preferably less than 4 micrometers, and more preferably about 3.8 micrometers. Nanoparticles reduce the average flow pore size of the medium while substantially maintaining the liquid flux (e.g., bubble point) on the filter. The maximum flow pore size of the filter medium is preferably less than about 40 micrometers, or less than about 25 micrometers, or less than about 20 micrometers.

[0084] The filter has a bubble point of less than about 20 (in / h20) or less than about 15 micrometers (in / h20). The bubble point is defined herein as the amount of force required to make the liquid pass through the substrate (i.e., the higher the value, the more difficult it is to make the liquid pass through the substrate).

[0085] In an exemplary embodiment, the membrane has a porosity value of at least 50% or 40%, preferably at least 20% or 5%. The porosity value is defined as the non-solid or pore volume fraction of the total material volume.

[0086] In various embodiments, the substrate includes a porous membrane. The porous membrane may have a thickness suitable for a particular application. In some embodiments, the membrane has a thickness of about 0.2 mm to about 5 mm, preferably about 0.5 mm to about 3 mm.

[0087] In some embodiments, the filter medium may include a structure comprising mixed or entangled chopped fibers and / or filaments. As used herein, chopped fibers refer to fibers of finite length. Filaments, as used herein, refer to fibers having a substantially continuous length. In some embodiments, the substrate may include chopped coarse fibers, microfibers, and / or fine fibers. As used herein, "fine fiber" refers to a fiber having a diameter of less than 1 micrometer, "coarse fiber" refers to a fiber having a diameter of greater than 10 micrometers, and "microfiber" refers to a synthetic fiber having a diameter of less than 10 micrometers.

[0088] In some embodiments, nanoparticles are bonded to fibers via mechanical entanglement. This mechanical bonding may be aided by adhesives or binders, as discussed in more detail below. In some embodiments, the nanoparticles are not curled (i.e., they do not include the pronounced wavy, curved, coiled, serrated, or similar shapes associated with nanoparticles in a relaxed state). In other embodiments, the nanoparticles may have a curled-body structure with discrete lengths. For example, when these curled nanoparticles with discrete lengths are attached to fibers, they become entangled with each other and are also firmly attached to, adhered to, and attached around the fibers, thereby forming modified fibers. In other embodiments, the attachment of nanoparticles to microfibers is achieved via electrostatic attraction and / or van der Waals attraction between the fibers and nanoparticles.

[0089] Filters, such as liquid filters, are also provided that include nanoparticles dispersed at a certain depth within the filter. In some embodiments, the filter media may include one or more support layers incorporated into the filter media, such as a loosely woven fabric layer, a plastic mesh layer (e.g., a polypropylene mesh), a mesh, a screen, a flow channel spacer, a channel depth layer, a rigid mesh plastic tube, a central core support, an outer wrapping, a protective sleeve, a pleated support, etc. In some embodiments, a polymer layer, membrane, or thin film is provided that includes one or more pores for gas or liquid to flow through, wherein nanoparticles are arranged at a certain depth within the polymer layer. The nanoparticles may be incorporated into these support layers and / or into any of the filter media incorporated into these support layers.

[0090] For example, the support layer may include a channel depth layer, which increases volumetric filtration capacity while extending the lifespan of the filter media. Nanoparticles may be incorporated into the channel depth layer. This type of filter media is particularly suitable for use as a gradient structure filter in automotive fuel filters and is described in more detail in U.S. Patent No. 9,555,353, the entire disclosure of which is incorporated herein by reference for all purposes.

[0091] Figure 1A representative filter medium, porous membrane, or substrate 10 comprising a plurality of fibers 12 and nanoparticles 14, manufactured by the system and method described above, is shown. The substrate 10 has a first surface 16 and a second surface 18 opposite to the first surface 16, defining a width or thickness between the first surface 16 and the second surface 18. The nanoparticles 14 have been deposited into the substrate through the first surface 16. As shown, the nanoparticles 14 penetrate through the first surface 16 into the substrate 10 to a “certain depth” between the first surface 16 and the second surface 18. In some embodiments, the nanoparticles 14 penetrate from the first surface to at least 25% of the width or thickness between the first surface 16 and the second surface 18, or more preferably at least about 50% of the thickness. In other embodiments, the nanoparticles 14 substantially penetrate throughout the substrate 10 from the first surface 16 to the second surface 18.

[0092] Nanoparticles 14 preferably comprise individual nanoparticles that have been broken up, separated, and isolated from each other before being dispersed into the substrate 10, as discussed above. Thus, nanoparticles 14 do not exist in the fibrous product in the form of layers and do not have obvious clumps or bundles of nanoparticles. This allows the nanoparticles to be more dispersed throughout the substrate, which, in some applications (e.g., gas or air filters), provides more efficient filtration to remove contaminants. Furthermore, this results in a greater areal density (in grams per square meter (gsm)) or “addition amount” of the nanoparticles within the material. The term “addition amount” is used herein to refer to the areal density (gsm) of a material, fiber, or particle in a thin layer, sheet, or film of material.

[0093] In some implementations, the nanoparticles may contain approximately 0.1 g / m³. 2 Approximately 20 g / m 2 Preferably, it should be at least about 2.0 g / m 2 The specific amount added, or the areal density, may depend on the application. For example, the applicant has found that a higher areal density or addition amount will improve the efficiency of the filter media in removing contaminants. Therefore, the specific amount of nanoparticles added may depend on the desired efficiency of the filter media.

[0094] Figure 2A filter medium or substrate 20 comprising a plurality of fibers 12 and nanoparticles 24, manufactured by the system and method described above, is shown. As shown, the nanoparticles 14 permeate the entire width of the substrate 20 from the first surface 16 to the second surface 18. In some embodiments, the nanoparticles 14 are substantially dispersed throughout the fibers 12 of the substrate, as shown. In some embodiments, the density of the nanoparticles located at the first surface 16 differs from the density of the nanoparticles dispersed in the central portion of the substrate 20 between surfaces 16 and 18 by less than 50%. In some embodiments, this difference is less than 25%, preferably less than 10%. In some embodiments, the amount or number of individual nanoparticles dispersed in the central portion of the substrate 20 is at least about 50%, preferably at least about 75%, and more preferably at least about 90% of the amount of individual nanoparticles dispersed at or near the first surface 16.

[0095] In other embodiments, the nanoparticles 14 are arranged in a density gradient from the first surface 16 to the second surface 18. For example, Figure 3 A substrate 30 is shown, wherein nanoparticles 14 form a density gradient, wherein the density of nanoparticles 14 disposed near a first surface 16 is higher than the density of nanoparticles 14 disposed near a second surface 18. In some embodiments, the difference between the density of nanoparticles located at the first surface 16 and the density of nanoparticles dispersed at the second surface 18 is greater than about 75%. In some embodiments, the difference is greater than 50%. In some embodiments, the difference is greater than 25%. In some embodiments, the amount or number of individual nanoparticles dispersed at or near the second surface 18 is less than about 50% of the amount of individual nanoparticles dispersed at or near the first surface 16, preferably less than about 25%, and more preferably less than about 10%.

[0096] Figure 3 The density gradient shown from the first surface 16 to the second surface 18 can be substantially linear. Alternatively, the density of the nanoparticles 14 can decrease from the first surface 16 to the second surface 18 in the form of a series of discrete steps, or the gradient can be random (i.e., the decrease in density is generally not linear or stepwise).

[0097] In other embodiments, nanoparticles may be added to the substrate from both the first and second surfaces 16, 18. In these embodiments, the areal density or "addition amount" at the first surface 16 and the second surface 18 may be substantially equal to each other, or they may vary depending on the application. In these embodiments, the areal density or "addition amount" in the middle of the substrate is lower than that at the surfaces 16, 18. For example, the areal density in the middle of the substrate may be about 75% of the areal density at the surfaces 16, 18, or it may be about 50%, 40%, or 25%.

[0098] Imaging techniques can be used, for example, to measure the distribution of nanoparticles across the thickness of the filter medium. A magnified image of the fiber product taken at a horizontal cross-section at the midpoint of the product's thickness using an electron microscope or other techniques can be compared to images taken at the top or bottom surface of the product, or all three images can be compared, to determine the degree of variation in the amount of deposited nanoparticles. Computer image analysis can be employed. For example, in... Figure 3 In this process, cross-sections can be taken at point AA and at point BB. Top views of each cross-section can be obtained using electron microscopy, scanning electron microscopy, and other microscopes. For example, the top view of the cross-section taken at point AA can be compared with the top view taken at point BB. The number of microfibers, nanoparticles, or both in samples of the same two-dimensional size can be evaluated and compared. Furthermore, imaging techniques can be used on three-dimensional samples. These techniques can be used to evaluate fiber orientation and other properties. These techniques can be used to determine whether nanoparticles have been deposited to a certain depth in the substrate, substantially deposited in most of the substrate, substantially deposited throughout the entire depth of the substrate, or deposited at a certain depth in the substrate.

[0099] The fibers of the substrate under consideration can be manufactured by any method, including but not limited to thermal bonding or ultrasonic bonding, cellulose wet web forming, glass wet web forming, synthetic wet web forming, composite wet web forming, needle punching, melt blowing, air-blowing, spinneret, gel spinning, melt spinning, wet spinning, dry spinning, island-type short fibers or spunbond, segmented disc short fibers or spunbond, etc. Such methods are described in U.S. Patent Nos. 4,406,950, 6,338,814, 6,616,435, 6,861,142, 7,252,493, 7,300,272, 7,309,430, 7,422,071, 7,431,869, 7,504,348, 7,774,077, 9,522,357, 9,993,761 and 2009 / 266,759, the full disclosures of which are incorporated herein by reference for all purposes.

[0100] The fibers under consideration can have a variety of cross-sectional shapes, including but not limited to circular, bean-shaped, dogbone-shaped, trefoil-shaped, barbell-shaped, bowtie-shaped, star-shaped, Y-shaped, etc. These shapes and / or other conventional shapes can be used in various embodiments to obtain the desired performance characteristics. The fibers in the substrate are held together by thermal bonding, chemical bonding, entanglement, or the use of adhesives (such as glues).

[0101] The fiber can be a man-made fiber or a natural fiber. Suitable materials for fibers include, but are not limited to, metal fibers, carbon fibers, polypropylene (PP), polyester (PET), PEN polyester, PCT polyester, polybutene (PBT), ethylene polyester (PET), polylactic acid (PLA), polyamide (PA), copolyamide, polyethylene, high-density polyethylene (HDPE), low-density polyethylene (LDPE), cross-linked polyethylene, polycarbonate, polyacrylate, polyacrylonitrile, polyfuran, polystyrene, styrene-maleic anhydride, polymethylpentene, cyclic olefin copolymers or fluorinated polymers, polytetrafluoroethylene, perfluoroethylene and hexafluoropropylene or copolymers with PVDF (such as P(VDF)). -TrFE)) or terpolymers (such as P(VDF-TrFE-CFE)), propylene, polyimide, polyetherketone, cellulose esters, nylon and polyamide, polymethacrylic acid, poly(methyl methacrylate), polyoxymethylene, polysulfonate, acrylic acid, styrene-acrylic acid, pre-oxidized acrylic acid, fluorinated acrylic acid, vinyl acetate, vinyl acrylic acid, ethylene vinyl acetate, styrene-butadiene, ethylene / vinyl chloride, vinyl acetate copolymers, latex, polyester copolymers, carboxylated styrene acrylic acid or vinyl acetate, epoxy resins, acrylic multipolymers, phenolic resins, polyurethane, cellulose, styrene, or any combination thereof. Other conventional fibrous materials are also considered.

[0102] The fibers can include fibers of varying sizes, typically having a diameter of about 1 to about 1000 micrometers and a length of about 1 / 2 to 3 inches. The fibers can be configured as a gradient density medium, where the pore size decreases from the upper surface (upstream) to the lower surface (downstream) of the filter to increase capture efficiency and dust holding capacity. This configuration also allows for the dispersion of different amounts of nanoparticles into the filter medium at different depths. For example, the upstream side of the filter medium can have the largest fiber size to allow for more void space and a higher nanoparticle density, while the downstream side of the filter medium has smaller fibers to provide a lower nanoparticle density. Alternatively, this structure can be inverted to provide a higher nanoparticle density in the downstream portion of the filter medium.

[0103] Fibers in the medium can be held together by thermal bonding, chemical bonding, or entanglement. Bicomponent fibers can be used, particularly in mechanical filtration, and these fibers are formed by extruding two polymers from the same spinneret, both polymers being contained within the same filament. Suitable materials for bicomponent fibers include, but are not limited to, polypropylene (PP) / polyethylene (PE), polyethylene terephthalate (PET) / polypropylene (PP), etc.

[0104] In some embodiments, the substrate may include a “high-loft” filter medium comprising spunbonded or hot-air bonded carded fibers. As used herein, the term “high-loft” refers to a void volume greater than the total solids volume. In hot-air bonded carded nonwoven fibers, the loft of the substrate can be controlled in various ways known to those skilled in the art. For example, loft can be increased by applying less compressive force to the medium during the bonding process. In another instance, high-loft nonwoven materials can be manufactured using fibers with a greater thickness (e.g., greater than 3 denier, such as 5 denier or greater, 6 denier or greater) (discussed in more detail below). In other embodiments, loft can be increased by using non-concentric bio-component fibers, such as… Figure 5C As shown, and discussed in more detail below.

[0105] In some embodiments, the fibers may include a silicone-based coating to improve the efficiency of the filter media in capturing contaminants, particularly those in the E2 and E3 particulate groups. The silicone-based coating may include a reactive silicone emulsion. Silicone emulsions may include, for example, dimethyl silicone emulsions, amino-based silicone emulsions, organofunctional silicone emulsions, resin-based silicone emulsions, film-forming silicone emulsions, etc. In one embodiment, the reactive silicone emulsion comprises an amino-functionalized polydimethylsiloxane and / or polyethylene glycol monotridecyl ether. Suitable silicone coatings are described in commonly assigned U.S. Patent Application No. 14 / 464,484, filed September 11, 2023, the entire disclosure of which is incorporated herein by reference.

[0106] Filter media may contain charge additives to alter the charge of the fibers and increase the stability and / or duration of the charge in the filter. This improves the overall filtration efficiency of the filter without compromising other important filter properties, such as lifespan, dust holding capacity, and bubble point or flow rate through the filter. Charge additives suitable for charging are described in commonly assigned Provisional Patent Application No. 63 / 410,731, filed September 28, 2022, the entire disclosure of which is incorporated herein by reference for all purposes.

[0107] The fibers can have a thickness suitable for the application. In some embodiments, the size of at least one dimension of the fiber is about 1 to about 10,000 micrometers, or about 1 to about 1,000 micrometers, or about 10 to 100 micrometers. The thickness of the fiber can also be measured in deniers, which is a unit of measurement for the linear mass density of the fiber. In some embodiments, the linear density of the fiber can be about 1 denier to about 10 deniers. Nanoparticles are fibers with at least one dimension having a size of about 1 to about 1,000 nanometers, or about 1 to about 100 nanometers. The size of the aforementioned fibers and nanoparticles can be diameter or width, depending on the shape of the fiber or nanoparticle.

[0108] In some embodiments, the filter medium may include at least two different fiber thicknesses or linear densities to provide at least two different filter layers within the same filter medium. For example, in some cases, a portion of the filter medium will include fibers with a linear density greater than 3 denier, such as 5 denier or greater, or 6 denier or greater. Another portion of the filter medium will include fibers with a more standard linear density of 3 denier or less. This dual-layer filter medium creates a first filtration section and a second filtration section, the first filtration section primarily utilizing high-density nanoparticles within the thicker fibers to filter contaminants, and the second filtration section primarily utilizing fibers with a lower linear density to filter contaminants, but both sections may contain nanoparticles dispersed throughout the fibers. In some embodiments, the filter medium may include three or more separate sections or layers, each with a different denier fiber range.

[0109] Figure 4 A dual-layer filter medium is shown, comprising a first substrate 40 having a first surface 42 and a second surface 44 opposite to the first surface; and a second substrate 50 having a first surface 52 and a second surface 54 opposite to the first surface. The second surface 44 of the substrate 40 is bonded to the second surface 54 of the first substrate in any manner known to those skilled in the art. The first substrate 40 comprises fibers 46 with a relatively low linear density (e.g., about 3 denier or less). The second substrate 50 comprises fibers 56 with a relatively high linear density (e.g., about 3 denier or greater, such as 5 denier, 6 denier or greater). The second substrate 50 also comprises individual nanoparticles 58 dispersed throughout the fibers 56 and bonded to and / or retained by the second substrate 50. The first substrate 40 may or may not contain nanoparticles.

[0110] The first substrate 40 is configured to primarily utilize fibers 46 to filter contaminants, but as previously mentioned, the first substrate 40 may also contain nanoparticles. The second substrate 50 is configured to utilize both fibers 56 and nanoparticles 58 to filter contaminants.

[0111] In some embodiments, the substrate may contain additives, such as antibacterial and / or antiviral compositions, such as silver, zinc, copper, silicone, tributyltin, or organic compounds containing chlorine, bromine, or fluorine compounds.

[0112] Fibers can include biological component fibers, which comprise two or more different fibers bonded together. Fibers can contain the same or different materials.

[0113] In some embodiments, the filter media (i.e., fibers and / or nanoparticles) may be electrostatically charged, enabling the capture of contaminants, for example, by mechanical and electrostatic filtration. The bond between the fibers and nanoparticles can also be enhanced by electrostatically charging the nanoparticles, fibers, or both. For example, in some embodiments, the fibers are electrostatically charged, allowing mechanical filtration through the nanoparticles while simultaneously enabling electrostatic filtration through an electret substrate. The electrostatic or electret substrate may be a highly porous triboelectric filter media manufactured by carding and needle punching. In one embodiment, it is preferable to deposit the nanoparticles into the substrate prior to needle punching, and then needle the electrostatic fibers and nanoparticles together.

[0114] Electrostatic charging of substrates, nanoparticles, or both can be performed using triboelectric charging, corona discharge, electrostatic fiber spinning, hydrocharging, charging rods, or other known methods. Corona charging is suitable for charging single polymer fibers or fiber blends or fabrics. Triboelectric charging can be applied to charging fibers with different electronegativity. Electrostatic fiber spinning combines polymer charging and fiber spinning into a single process. Charge additives suitable for triboelectric charging are described in commonly assigned Provisional Patent Application No. 63 / 410,731, filed September 28, 2022, the entire disclosure of which is incorporated herein by reference for all purposes.

[0115] Nanoparticles with different triboelectric properties relative to fibers can be selected to enhance particle removal by utilizing the triboelectric effect. In this method, the generated nanoparticles are formed in an electric field and are less susceptible to contamination by chemicals that can mitigate the triboelectric effect. Nanoparticles with different adsorption properties or surface charge characteristics than coarse fibers can also be used, for example, for oil or water filtration. This difference can be used to enhance or create a local electric field gradient within the filter media to enhance particle removal. Nanoparticles and coarse fibers can have different wetting properties.

[0116] In some embodiments, the filter medium may be included in a film or layer having pores, gaps, or perforations. The pores may be embossed into a pattern (e.g., circular, rhomboid, hexagonal, rectangular, triangular, etc.) and then stretched until pores are formed in the thinned areas created by the embossing. This open-cell substrate may be formed from a variety of polymers (e.g., polypropylene, polyethylene, high-density polyethylene (“HDPE”), etc.). The polymer layer may, for example, include an extruded membrane. Open-cell membranes are commercially available and sold under the trademark Delnet®. The substrate is provided in the form of rolls into which nanoparticles are deposited in a roll-to-roll process.

[0117] Fibers can include biological component fibers, which comprise two or more different fibers bonded together. Fibers can contain the same or different materials.

[0118] Figures 5A-5C Different examples of bio-component fibers that can be used with the porous membranes disclosed herein are shown. Figure 5A A fiber 60 having a core fiber 62 and surrounding sheath fibers 64 is shown. In this embodiment, the core 62 and the sheath are substantially concentric. Figure 5B A bio-component fiber 70 is shown having first and second fibers 72 and 74 arranged side by side. Figure 5C A biocomponent fiber 80 having core fibers 82 and sheath fibers 84 is shown. In this embodiment, the core 82 is non-concentric with respect to the longitudinal axis of the sheath 84, which increases the overall bulkiness of the biocomponent fiber. Of course, other configurations are also possible. For example, the core may include shapes other than circular, such as dog bone shape, square, triangular, rhomboid, etc. Alternatively, the fiber may contain multiple cores, or may be divided into three, four or more quadrants.

[0119] Figure 6 A representative liquid filter 101 produced using porous membranes in various embodiments is shown. The porous membranes are rolled into cylinders, cones, or other suitable shapes and can be used in applications such as gas turbine and compressor inlet filters, and plate filters. The cartridge is a tubular filter medium encapsulated within a housing. The flow direction in a cartridge filter is typically from the outside to the inside of the cartridge. The cartridge is typically made of synthetic or natural fibers and small metal wires. A core made of stainless steel, tin-plated steel, or polypropylene is present along the axis of the tubular cartridge to support the media material. A purer filtrate is collected at the core.

[0120] Figure 7 A representative bag filter 102 produced using filter media and / or porous membranes as described herein in various embodiments is illustrated. The bag filter 102 includes a porous membrane having short fibers and nanoparticles dispersed at a certain depth within a substrate. Bag filters are among the most popular filtration devices. In this device, the process liquid passes through a permeable bag with micropores that acts as the filter media. Solid particles larger than the pores are trapped and accumulate inside the bag. Its end has a sealing ring, typically made of stainless steel or plastic, to secure the bag within the filter container.

[0121] Figure 8 A representative metal filter medium 104 produced using filter media and / or porous membranes according to various embodiments described herein is shown. Filter media 104 comprises a metal screen or perforated plate 106 made of stainless steel, copper, or aluminum. Filter media 104 is particularly suitable for filtering liquids at elevated temperatures and high flow rates, as well as for corrosive liquids.

[0122] Figure 9A representative synthetic filter 108 is shown, manufactured using filter media and / or porous membranes according to various embodiments described herein. The synthetic filter 108 comprises polymeric materials such as polyester, nylon, polypropylene, and / or fluoropolymers such as PVDF and PTFE. The polymeric material may be a fabric having monofilaments or multifilaments.

[0123] Figure 10 A representative pleated filter cartridge 112 is shown, produced using filter media and / or porous membranes according to various embodiments described herein. The filter cartridge 112 is particularly suitable for surface filtration and can be constructed by pleating the media attached to its ends to provide a larger filtration area in a minimal volume.

[0124] Figure 11 A representative spunbond filter cartridge 114 is shown, produced using filter media and / or porous membranes according to various embodiments described herein. Filter cartridge 114 is particularly suitable for depth filtration and can be constructed by thermally bonding fibers together while maintaining a gradual density gradient. This increases the durability and strength of the filter cartridge.

[0125] Figure 12 A representative wound filter cartridge 116 is shown, produced using filter media and / or porous membranes according to various embodiments described herein. The wound filter cartridge 116 is particularly suitable for depth filtration and is constructed by rotating the thread around the core to create layers of the filter and generate a density gradient that gradually increases from the outer surface to the inner surface.

[0126] Figure 13 A membrane filter cartridge 118 manufactured using filter media and / or porous membranes according to various embodiments described herein is shown. Filter cartridge 118 is particularly suitable for the food and beverage, pharmaceutical, UPW, and semiconductor industries. Filter cartridge 118 may contain PTFE, PES, PVDF, and / or nylon and may have a pleated filter structure. The pleated structure provides each pleated membrane filter cartridge with a large filtration area and high dirt-holding capacity, thus effectively increasing its service life.

[0127] Figure 14 An industrial liquid filtration device 134 comprising filter media and / or porous membranes as described herein in various embodiments is illustrated. As shown, the filtration device 134 includes a generally cylindrical outer metal housing 135 having an inlet 136 for receiving unfiltered liquid and an outlet 137 for discharging filtered liquid. A filter media cartridge 138 extends through the interior of the housing 135 such that liquid must flow through the filter cartridge 138 before exiting the outlet 137 of the housing 135. As described above, the cartridge 138 includes a filter media 139 comprising a fibrous substrate incorporating nanoparticles therein.

[0128] Figure 15A multi-bag filter 142 comprising filter media and / or porous membranes as described herein in various embodiments is illustrated. Filter 142 is a small filter, particularly suitable for homes, offices, and laboratories. As shown, filter 142 includes a first housing 143 and a second housing 144, each housing comprising a bag filter (not shown), for example... Figure 7 The bag filter shown is also described. Filter 142 can also be used as a pretreatment for downstream processes, where solid removal is crucial for achieving product quality and safety, as well as maintaining the efficiency of downstream equipment. Filter 142 can be used in piping, pumping systems, or manufacturing processes for human consumption, such as beverages and drinking water.

[0129] Figure 16 A rotary drum filter 152 comprising filter media and / or porous membranes as described herein in various embodiments is illustrated. Filter 152 is particularly suitable for use as an industrial filtration device for filtering liquid streams with high solids concentrations in continuous processes. As shown, filter 152 includes a drum 154 partially immersed in a slurry under vacuum pressure. The side surfaces of drum 154 include one or more filter media (not shown). As drum 154 rotates, the liquid is evacuated to a vacuum, and solids are retained on the surface of drum 154. Drum 154 may also include a scraping system to discharge filter cake, thereby preventing its accumulation on the filter media.

[0130] Figure 17 A filter press 162 is shown, comprising filter media and / or porous membranes according to various embodiments described herein. The filter press 162 is particularly suitable for use as an industrial filtration device for filtering liquid streams with high solids concentrations in batch processes. The filter press 162 comprises a plurality of plates 164, each plate comprising a filter media (not shown) comprising a fibrous substrate having nanoparticles incorporated therein, as described above. The slurry is pumped through the plates 164 and then dewatered under high pressure.

[0131] Figure 18AAn embodiment of a fuel filter 172 comprising filter media and / or porous membranes as described herein is shown. As shown, the filter 172 includes a main housing 173, which protects the internal components of the filter 172 and is typically made of steel. The interior of the housing 173 is typically pressurized to prevent overflow. The housing 173 includes a base plate 174 that connects the housing 173 to a fixing assembly (not shown) for mounting the filter, preventing fuel leakage, and maintaining pressure within the filter 172. The housing 173 also includes a central tube 175, which serves as a support for the filter and prevents it from collapsing inward. The tube 175 also serves as an outlet for filtered fuel and is typically made of a material stronger than steel. An end cap 176 holds the filter media 177 in place and attaches it to the filter media 177 with a suitable adhesive. The end cap 176 also serves to prevent leakage. A compression spring 178 holds the internal components under varying pressure. As described above, the filter media 177 includes a substrate in which nanoparticles are incorporated. The substrate typically comprises cellulose or a synthetic material. The filter 172 may also include: a bypass valve that provides a mechanism for the fuel to bypass the filter medium 177; and a water sensor for detecting the presence of water in the diesel fuel, which is installed in the fuel coarse filter.

[0132] Figure 18B A fuel filter 184 is shown, specifically designed for vehicles and capable of being connected between the vehicle's fuel pump and carburetor. Filter 184 is used to capture any water or foreign particles that are not filtered out in the fuel pump sediment cup and the coarse filter of the fuel tank filter unit. Filter 184 includes a housing 185 in which multiple layers of filter media 186 surround a double-beaded structure 187. Filter media 186 may be made of a suitable ceramic material. Fuel entering the housing 185 passes through the ceramic filter media 186, which separates foreign particles. The filtered fuel remains in the filter media 186, while water and sediment are collected in a cup that can be removed for cleaning.

[0133] Figure 19 A CMP filter 192 is illustrated, comprising filter media and / or porous membranes of various embodiments as described herein. Filter 192 is particularly suitable for semiconductor manufacturing processes to remove large slurries while maintaining desired slurry formulations and chemistry, and / or to planarize uneven areas by combining the chemical (acidic or alkaline) slurry of microabrasives with the mechanical forces provided by polishing. In multi-stage metallization processes, defects in the underlying layers are amplified with each new metal layer added. CMP allows for subsequent photolithography processes with greater precision. Filter 192 includes one or more filter media capable of filtering ILD, STI, tungsten, bulk copper, barrier copper, and other slurries to reduce microscratches, arc scratches, ripples, and improve process stability.

[0134] Figure 20 A water filter 194 comprising filter media and / or porous membranes as described herein in various embodiments is illustrated. The filter 194 is designed to ensure the purity of acids, alkalis, and solvents used in semiconductor manufacturing processes. For example, the filter 194 may be particularly suitable for removing colloidal contaminants, such as silica bacterial decomposition products in manufacturing processes. The filter 194 mitigates the harmful effects of metal ion and particulate contamination.

[0135] Figure 21 A gas pipeline filter 196 for filtering dry gases is shown, comprising filter media and / or porous membranes according to various embodiments described herein. The pipeline filter 196 includes a housing 197 having a gas inlet 198 and a gas outlet 199, wherein a reloadable filter cartridge 201 is located within the housing 197 between the inlet 198 and the outlet 199. The filter 196 also includes a discharge port 203 configured to be mounted on a pipeline to remove large solid impurities from fluids, thereby ensuring the proper and safe operation of equipment such as compressors, pumps, instruments, etc.

[0136] Other types of liquid filters that can be developed using the materials disclosed herein include conical cartridges, spunbond cartridges, square-end cap cartridges, activated carbon cartridges, reverse osmosis membrane cartridges, alkaline cartridges, battery separators, ultraviolet cartridges, bag filters, V-shaped compact filters, plate filters, flat-panel filters, pleated or non-pleated bag cartridges, and clean-in-place (CIP) filters. More complete descriptions of various filters that may include the filter media described herein can be found in U.S. Patent Application No. 18 / 297,217, filed April 7, 2023, and U.S. Provisional Patent Application No. 63 / 517,656, filed August 4, 2023, the entire disclosure of which is incorporated herein by reference for all purposes.

[0137] This document provides systems, apparatus, and methods for producing filter media, porous membranes, and products containing filter media or porous membranes (e.g., liquid filters). Systems and methods are also provided for isolating individual nanoparticles in a gaseous medium, such as air, helium, nitrogen, oxygen, carbon dioxide, etc. (rather than a liquid), and for dispersing the nanoparticles into another product, membrane, layer, or substrate via an airflow, aerosol, evaporator, spray, or other suitable delivery mechanism.

[0138] Figure 22The entire system 110 for manufacturing the filter media and other products described herein is schematically illustrated. As shown, system 110 includes a feeder 120 for advancing layers 130 of fibers or other materials during the manufacturing process. System 110 also includes a coater 140, a nanoparticle dispersion system 150, and a heating and / or drying device 160. In some embodiments, system 110 also includes a vacuum or other negative pressure source 170 located below the substrate 130, opposite the fiberization system 150.

[0139] In one embodiment, the feeder 120 includes a winder 122 located downstream of the process and an unwinder 124 located upstream, which continuously winds the fiber layer 130 through the system 100. In some embodiments, the feeder 120 may also include a support surface (not shown) extending between the winders for supporting the fiber layer 130 as it moves downstream through the system 100. In other embodiments, the fiber layer is unwound directly from the unwinder 124 to the winder 122 without the need for another support surface.

[0140] The coating machine 140 is configured to spray droplets of adhesive or bonding material (e.g., glue or adhesive) onto the fiber layer 130, allowing nanoparticles to adhere to the fibers within the layer 130 to form a stable matrix. The adhesive is preferably present in a relatively small amount to bond individual nanoparticles to the fibers throughout the layer 130. In a preferred embodiment, the coating machine 140 includes a nozzle sized to generate adhesive droplets with a diameter of approximately 20 to 30 micrometers to increase the penetration depth of the adhesive through the layer 130. Of course, droplet size can be affected by many other parameters, including air pressure, air volume, air temperature, humidity, spray nozzle design, the rheology / viscosity of the adhesive, carrier, etc.

[0141] Of course, it should be recognized that coating a substrate with an adhesive or bonding material can be achieved by other coating methods, including ultrasonic spraying, dip coating, spin coating, gravure coating, licker roller coating, screen coating, powder coating, electrostatic coating, sputtering coating, or similar coating techniques.

[0142] In some embodiments, an adhesive resin is used, and the adhesive resin can be cross-linked after the adhesive is applied to the fiber layer 130. Adhesion (water resistance / solvent resistance) can be promoted by self-cross-linking during solvent evaporation in the adhesive formulation or by thermal activation during the drying process. For some adhesives, cross-linking can be achieved by electromagnetic radiation of high-energy wavelengths (including but not limited to RF, UV, or electron beams). The amount of adhesive can be controlled by adjusting the nozzle size of the sprayer 140 or by controlling the flow rate of the adhesive composition.

[0143] In some embodiments, the adhesive may contain surfactants to reduce the surface or interfacial tension of the adhesive, thereby improving its dispersibility and wetting properties, and making it easier for the adhesive to penetrate into a substrate to a certain depth. Suitable surfactants for use with the adhesives disclosed herein include nonionic, anionic, cationic, and amphoteric surfactants, such as sodium stearate, 4-(5-dodecyl)benzenesulfonate, sodium dodecylbenzenesulfonate wetting agents, docusate (sodium dioctyl sulfonate), alkyl ether phosphates, benzalkonium chloride (BAC), perfluorooctane sulfonate (PFOS), etc.

[0144] In some embodiments, the sprayer 140 is located upstream of the nanoparticle dispersion system 150 to spray the adhesive before the nanoparticles are deposited. In other embodiments, the sprayer 140 is located downstream of the system 150 so that the adhesive can be sprayed after the nanoparticles are deposited. In other embodiments, the system 100 includes two sprayers; one is located upstream of the system 150, and a second sprayer (not shown) is located downstream of the system 150 to coat the fiber layer 130 with a second adhesive after the nanoparticles are deposited.

[0145] In some implementations, each sprayer 140 has more than one nozzle head. For example, the nozzle heads may be arranged in series to achieve better uniformity or increase the fiber spraying width. Alternatively, the nozzle heads may be placed parallel (i.e., across the width of the substrate) to ensure that the adhesive is applied across the entire width of the substrate.

[0146] In a preferred embodiment, a negative pressure source or vacuum source (not shown) is arranged below the fiber layer 130, opposite the sprayer 140, to increase the penetration depth and uniformity of the adhesive. The negative pressure source can be any suitable suction device that draws the adhesive through the substrate, such as a suction pump.

[0147] In some embodiments, the fiber layer comprises its own adhesive composition. In these embodiments, an adhesive may or may not be added to the fiber layer. In one such embodiment, the fiber layer comprises biological component fibers, one component comprising an outer sheath at least partially surrounding an inner core. In some embodiments, the sheath and core may be substantially concentric with each other. In other embodiments, the core may be non-concentric with the sheath. In other embodiments, the core and sheath may be arranged side-by-side with each other. Of course, other configurations are also possible. For example, the core may comprise shapes other than circular, such as dog-bone shaped, square, triangular, rhomboid, etc. Alternatively, the fiber may comprise multiple cores, or may be divided into three, four, or more quadrants.

[0148] The sheath may contain a material that binds to the nanoparticles. For example, the sheath may contain a material that becomes viscous and / or fluid upon heating and / or drying. During the heating / drying step, the sheath portion of the fiber is heated to its melting point until it becomes viscous and / or fluid to bind the nanoparticles to the fiber layer. In a preferred embodiment, bonding and drying are performed simultaneously within the drying apparatus 160.

[0149] Figure 23 A nanoparticle dispersion system 150 (or fibrillation system) for converting a group of nanoparticles into individual nanoparticles is schematically illustrated. As used herein, the term "fibrillation" refers to the conversion (e.g., opening, separating, isolating, and / or individualizing) of clusters, clumps, or other groups of nanoparticles that may or may not be entangled into each other into at least one individual nanoparticle with a size less than 1 micrometer.

[0150] As shown in the figure, system 150 includes a feeder 200, such as a hopper, for introducing larger or larger clusters / agglomerates of nanoparticles into system 150. The feeder 200 may include any suitable hopper device known to those skilled in the art and is preferably configured to introduce large particle clusters into the process at a specified rate, which will depend on the downstream fibrosis rate. Nanoparticles may be introduced continuously at the specified rate or at intervals at a specific rate. Large clusters of nanoparticles may be broken up before being introduced into the feeder 200.

[0151] It should be recognized that nanoparticles can be introduced into system 150 in a variety of different forms. For example, the original nanoparticles can be fabricated into long, separated fibers. In this form, the nanoparticles can be cut to obtain the desired aspect ratio.

[0152] System 150 also includes a separator 210, such as a mixer, for separating or breaking down large nanoparticle clusters / agglomerates into smaller clusters / agglomerates. Feeder 200 conveys nanoparticles into separator 210 in a stable and continuous manner by any mechanical means. The conveying speed will depend on various factors, such as the speed at which the substrate 130 travels along feeder 120 and the fibrosis rate of the nanoparticles. By controlling the amount of nanoparticles falling into separator 210, the amount of nanoparticles dispersed in the substrate can be controlled, thereby enabling a continuous manufacturing process.

[0153] In one embodiment, the separator 210 includes a housing 212 having a first opening 214 coupled to a feeder 200 and a second opening 216 coupled to a downstream process. The second opening 216 is preferably sized to allow only clusters of nanoparticles of a given size to pass through. The separator 210 may include a plurality of rotatable blades (not shown) designed to rotate about a vertical axis within the housing 212 to separate and open coarse nanoparticle clusters. The blades may have the same or different pitch and camber to allow entangled fibers to sequentially break down or “open” as they are conveyed from the first opening 214 to the second opening 216. The following... Figure 28-34 An embodiment of a feeder 200 and a separator 210 for a continuous manufacturing process is described.

[0154] System 150 also includes an airflow extending throughout the system from separator 210 to nozzle 220 (discussed in more detail below). The airflow (along with a series of pumps discussed below) provides the power to move the nanoparticles through system 150. In one embodiment, the airflow is generated by an air compressor 230 configured to supply compressed air to the system, but it should be recognized that other forms of gas can be used to convey the nanoparticles through system 150.

[0155] System 150 includes one or more pumps for moving nanoparticle clusters throughout the system and ultimately moving individual nanoparticles. The pumps can include any suitable pump, such as a positive displacement pump, centrifugal pump, axial flow pump, etc. In one embodiment, a first pump 240 includes a first inlet fluidly coupled to an air compressor 230 via a first channel 242 and a second inlet fluidly coupled to a separator 210 via a second channel 244. Compressed air is drawn into the first pump 240, which creates a negative pressure (e.g., a vacuum) to draw nanoparticle clusters from the separator 210 into the pump (discussed in more detail below). System 150 may also include a second pump 250 and a third pump 260, each fluidly coupled to the outlet of the first pump 240. Similarly, the second pump 250 and the third pump 260 create a negative pressure to draw nanoparticle clusters through a third channel 252.

[0156] In some embodiments, pump 240 includes injector 300. For example... Figure 24As shown, each ejector 300 includes a motive fluid inlet 302 and a nanofiber inlet 304, which are coupled to an outlet 306 via a fluid channel 308. The fluid channel 308 includes a converging inlet nozzle 310, a diffuser throat 312, and a diverging outlet diffuser 314. High-pressure, low-velocity air is converted into low-pressure, high-velocity air, thereby generating the pressure difference required for suction. Based on the Venturi effect and Bernoulli's principle, a primary fluid medium (e.g., compressed air) is used to create a vacuum to draw nanoparticles into the ejector 300 and discharge them through the outlet 306. The diameter of the ejector 300 depends on the volumetric velocity of the compressed air, the suction requirement, the pressure drop, and the fluid pressure of the compressed air.

[0157] review Figure 23 The third channel 252 includes a connector 254 that divides the third channel 252 into two independent channels, each leading to the second pump 250 and the third pump 260. The connector 254 preferably includes a surface or wall arranged substantially perpendicular to the third channel 252, thus forming a T-shaped intersection. This surface can be any surface that obstructs the flow of nanoparticles through the channel, such as the inner wall of the channel at the junction, or other inner walls that change direction, such as curved surfaces, vertical surfaces, etc. Alternatively, the channel can include a wall or other surface arranged within the channel or protruding into the channel in the fluid path. In one embodiment, the channel extends to a substantially T-shaped connector comprising two independent channels extending from the connector. The second injector is configured to draw nanoparticles into the T-shaped connector at a speed sufficient to disperse at least some of the nanoparticles.

[0158] As the nanoparticle clusters move through the third channel 252, they are pushed against the surface or wall by the negative pressure applied by the second pump 250 and the third pump 260. The velocity of the nanoparticles relative to the connector 254 generates collisions with sufficient kinetic energy, causing at least some nanoparticle clusters to break into smaller nanoparticle clusters and / or individual nanoparticles with at least one dimension smaller than 1 micrometer.

[0159] To generate the kinetic energy required to break up the nanoparticle clusters, air is propelled throughout the system 150 at a speed of approximately 500 feet per minute (fpm) to approximately 10,000 feet per minute, preferably approximately 2,000 fpm to approximately 6,000 fpm. System 150 includes a sufficient amount of suction pressure, preferably at least approximately 20 psi. This suction pressure generates a total pressure of at least approximately 100 psi throughout the system.

[0160] In some embodiments, system 150 further includes a fourth fluid passage 262 and a fifth fluid passage 264 that couple the outlets of the second pump 250 and the third pump 260 to reactor 270. For example... Figure 25As shown, reactor 270 includes a top surface 272, a bottom surface 274, and an internal annular chamber 276 extending from the top surface 272 to the bottom surface 274. Reactor 270 also includes a central tube 275 having an open upper inlet 278 and an outlet 280. Reactor 270 may also include one or more upper outlets 282. Reactor 270 may be coupled to an energy source (not shown) configured to generate a vortex of swirling gas within the annular chamber 276. The energy source may include any suitable energy source, such as a pump, compressor, generator, etc. The swirling gas preferably flows from the bottom to the top of reactor 270 around the central tube 275 to cause nanoparticle clusters and individual nanoparticles to move upwards from the bottom surface 275 to the top surface 272.

[0161] In another embodiment, the generation of vortices does not require a separate energy source. In this embodiment, nanoparticle clusters 290 and individual nanoparticles 292 enter reactor 270 through bottom inlets 284, 285, 286, and 287. Inlets 284, 285, 286, and 287 are inclined upwards to facilitate the movement of nanoparticles around a central tube 275. In a preferred embodiment, at least one or more of inlets 284, 285, 286, and 287 are inclined such that the nanoparticles are substantially tangential to the central tube 275 when entering reactor 270. Once the nanoparticles enter annular chamber 276, their velocity vectors (velocity and direction) generate vortices within reactor 270, causing them to swirl around the central tube 275 and rise to the upper part of chamber 276. The swirling gas preferably flows from the bottom to the top of reactor 270 around the central tube 275 to move nanoparticle clusters and individual nanoparticles from the bottom surface 275 to the top surface 272. Nanoparticles 290 and 292 are blown from the bottom to the top of the reactor undisturbed. The eddies within chamber 276 can further break down (e.g., open, separate, and / or individualize) the nanoparticle clusters 290 as they pass through reactor 270.

[0162] In some embodiments, reactor 270 may also be coupled to an energy source (not shown) configured to generate vortices of swirling gas within annular chamber 276. The energy source may include any suitable energy source, such as a pump, compressor, generator, etc.

[0163] System 100 may also include another pump or negative pressure source coupled to the upper outlet 282. This negative pressure draws the fibers out of outlet 282, causing the fibers 290 to exit reactor 270. Since individual nanoparticles 292 are significantly lighter than tangled nanoparticles 290 that are still aggregated, these individual nanoparticles 292 are drawn into the upper inlet 278 of the central tube 275. Simultaneously, larger and heavier clusters of nanoparticles 290 that have not yet been decomposed are drawn out from upper outlet 284. Upper outlet 284 may be coupled to another pump (not shown) or to the first pump 240. In this way, the nanoparticle clusters 290 are reintroduced into the process for further decomposition, thus forming a refeed system for further decomposition of the remaining nanoparticle clusters.

[0164] The outlet 280 of the central tube 275 is coupled to the nozzle 220 (see...) Figure 23 Individual nanoparticles 292 are drawn into nozzle 220, where they are dispersed onto a substrate surface or into a fiber stream (discussed below). Nozzle 220 may comprise any suitable nozzle known to those skilled in the art. In one embodiment, nozzle 220 has multiple outlets whose external dimensions are customized according to the dimensions (i.e., area) of the substrate beneath nozzle 220. Nozzle 220 disperses the nanoparticles onto the substrate at a rate driven by the pressure of the entire system.

[0165] In some embodiments, system 100 includes more than one nozzle coupled to outlet 280 of reactor 270. The nozzles may be arranged on the substrate in any suitable manner (e.g., side-by-side, in series, in parallel, etc.).

[0166] It should be recognized that pump 240 or pumps 250, 260 can directly feed the nanofiber / air mixture into nozzle 220 (i.e., bypassing reactor 270). In this embodiment, the pressure within the system is designed to generate sufficient kinetic energy to break down or break up substantially all of the nanoparticles into individual nanoparticles, thus eliminating the need for reactor 270 to separate the nanoparticles from larger fiber clusters.

[0167] For reference Figure 26 Another embodiment of the nanoparticle dispersion system 320 will now be described. As shown, system 320 includes a separator 325 for separating larger or larger clusters of nanoparticles into smaller clusters that will pass through system 320. A first ejector 326 is coupled to the outlet of separator 325 for drawing nanoparticles from separator 325 into system 320. An air compressor (not shown) is also coupled to ejector 326 to provide motive fluid, as discussed above.

[0168] Similar to the previous implementation, the second ejector 330 and the third ejector 340 are coupled to the outlet of the first ejector 326. Nanoparticles are extracted from the first ejector 320 and pushed toward the surface of the T-shaped intersection 350 to break at least some of the nanoparticles into smaller clusters or individual nanoparticles.

[0169] Each of the second ejector 330 and the third ejector 340 has an outlet coupled to additional T-shaped intersections 360 and 370. As before, the nanoparticles are pushed toward the surface of the T-shaped intersections 360 and 370 for further decomposition. The T-shaped intersections 360 and 370 are each coupled to two fluid channels leading into the bottom 380 of the reactor. Therefore, the bottom 380 of the reactor has four separate inlets 382, ​​384, 386, and 388 for the passage of the nanoparticles. Each of these inlets is preferably inclined upwards and located at an opposite corner of the reactor. This allows the nanoparticles to enter the vortex of the reactor and then vortex upwards to the upper part 390 of the reactor.

[0170] As previously referenced Figure 25 The reactor discussed comprises an annular chamber with a central tube having an open upper end and a lower end coupled to a nozzle. Nanoparticles, sufficiently decomposed into individual nanoparticles, flow through the open upper end and into the central tube for dispersion through the nozzle. Heavier clusters of nanoparticles that have not yet decomposed exit the reactor through one of four independent outlets 392, 394, 396, and 398. Ejectors 410 and 420 provide the power for extracting nanoparticles from the reactor 400, as discussed above. Outlets 392 and 394 are each coupled to ejector 410 via a T-junction 412, and outlets 396 and 398 are each coupled to ejector 420 via a T-junction 422. In this configuration, nanoparticles flow from two channels into one channel as they pass through junctions 412 and 422.

[0171] Injectors 410 and 420 are each coupled to T-junctions 430 and 440, respectively. As previously discussed, nanoparticles are pushed into T-junctions 430 and 440 for further breakdown into individual nanoparticles. T-junctions 430 and 440 are then coupled to the bottom 380 of reactor 400 (via inlets 432, 434, 442, and 444). This allows the nanoparticles to return to reactor 400 for further processing. This process is repeated continuously for each nanoparticle cluster until it is completely broken down into nanoparticles and enters the nozzle through a central tube. As a final step, the individualized nanoparticles are sprayed from the nozzle onto any substrate or mixed with any fiber spinning stream. During this process, suction power reaches up to 20 psi and pressure reaches up to 100 psi.

[0172] In some embodiments, system 150 or 200 may include a separate control system that monitors the nanoparticles to determine when they break down into individual nanoparticles suitable for passage through the nozzle. The control system may, for example, simply monitor the pressure throughout the system to ensure sufficient pressure is applied to the nanoparticles to break them down. Alternatively, the control system may include various sensors arranged within the system to detect characteristics of the nanoparticles, such as weight or size. The sensors may be arranged, for example, within reactor 400, such that the control system can control various parameters of reactor 400, such as negative pressure applied to outlets 392, 394, 396, 398, the velocity of the vortex passing around the annular chamber, or the pressure applied to the central tube to draw the nanoparticles into the nozzle.

[0173] Figure 27 Another embodiment of a system 500 for manufacturing multilayer filter media is shown. As shown, system 500 includes a first unwinder 502 and a second unwinder 504, and a single winding machine 506 for winding a first substrate 510 and a second substrate 512 downstream of system 500. As in previous embodiments, system 500 may also include a support surface (not shown) for each substrate 510, 512. The first unwinder 502 and the second unwinder 504 are used to advance the first substrate 510 and the second substrate 512 into the process, where they are joined together and then wound onto the single winding machine 506, as described below.

[0174] System 500 includes a first spray gun 520 and a second spray gun 522, each located downstream of a first unwinder 502 and a second unwinder 504, for applying adhesive to a first substrate 510 and a second substrate 512. System 500 also includes a first fiberization system / device 530 and a second fiberization system / device 532, located downstream of each spray gun 520, 522. As previously discussed, the fiberization devices 530, 532 generate individual nanoparticles and disperse these nanoparticles onto the substrates 510, 512.

[0175] After the nanoparticles are dispersed into substrates 510 and 512, the two substrates are joined together at connection point 540 so that they can be advanced downstream together. The two substrates can be bonded to each other at this point, or they can simply be placed one on top of the other.

[0176] System 500 also includes a heater / drying device, such as an IR oven 550, located downstream of the junction 540 of the two substrates. The heating / drying device heats and dries the two substrates to bond them together and to bond the nanoparticles to the fibers within the substrates. The substrates may, for example, be laminated together.

[0177] In some embodiments, nanoparticles are dispersed in two substrates 510, 512. In one such embodiment, system 500 is designed such that the nanoparticles are dispersed through a first surface of each substrate. The substrates can then be joined together such that the first surfaces face each other. Alternatively, the first surfaces can face away from each other (i.e., the substrates are joined at a second opposing surface of each substrate). In yet another embodiment, the first surface of the first substrate is connected to the second surface of the second substrate.

[0178] Figure 28-44 An embodiment of a feed system 600 is shown for separating or breaking down larger clusters / agglomerates of nanoparticles into smaller clusters and / or individual nanoparticles, and then conveying these smaller clusters and / or individual nanoparticles to one of the aforementioned filter manufacturing systems. The feed system 600 is particularly suitable for introducing nanoparticles into a continuous manufacturing process at a controlled mass or volumetric flow rate (i.e., the amount, volume, or total mass of nanoparticles passing through the feed system 600 per unit time). Nanoparticles can be introduced continuously at a specified flow rate or intermittently at specific flow rates. The conveying speed will depend on various factors, such as the substrate 130 along the feeder 120 (see...). Figure 22 Factors such as the travel speed, the fibrosis rate of the nanoparticles, and the desired amount of nanoparticles dispersed in a substrate of a given area / volume can be considered. By controlling the quantity, mass, or volume of nanoparticles falling into the manufacturing system, the amount of nanoparticles dispersed in the substrate can be controlled, resulting in a continuous manufacturing process with improved quality and yield, as well as reduced cost and time. Furthermore, the system is scalable and produces filter media with minimal variation.

[0179] like Figure 28 and Figure 29 As shown, the feeding system 600 typically includes a container or bulk bin 602, such as a hopper, for receiving relatively large (i.e., large) clusters or bundles of nanoparticles, and a lifter 604 for elevating the nanoparticles to a dispersion system 606, which disperses the nanoparticles into the filter manufacturing system (as described above). Large clusters or bundles of nanoparticles may be partially broken up before being introduced into the bulk bin 602, and / or they may be partially or completely broken up and separated within the container 602. It should be appreciated that nanoparticles can be introduced into the feeding system 600 in a variety of different forms. For example, the raw nanoparticles can be fabricated as long, separated fibers, such as nanofibers, microfibers, etc. In this form, the nanoparticles can be cut to obtain a desired aspect ratio.

[0180] The bulk hopper 602 can be used as a separator, such as a mixer, to separate or break down large clusters / bundles of nanoparticles into smaller clusters / aggregates, or directly separate or break down into individual nanoparticles. In one embodiment, the bulk hopper 602 includes a plurality of rotatable screws or rotors 610 designed to rotate about an axis within the bulk hopper 602 to separate and open coarse nanoparticle clusters (see discussion in more detail below). Figures 30-33 ).

[0181] like Figure 30-32 As shown, rotor 610 can also be used to drive individual nanoparticles downward toward opening 612 at or near the bottom of container 602. Individual nanoparticles behave differently from macroscopic objects. Because the mass of nanoscale objects is so small, the attractive force of gravity between objects of this size is very small. Therefore, gravity has little or no effect on these particles (i.e., gravity does not automatically pull them downward toward opening 612). Opening 612 is coupled to collection container 620 (see...). Figure 29 This is used to collect the individual nanoparticles that have been broken in container 602 and send them to elevator 604 (discussed in more detail below).

[0182] like Figure 30 As shown, rotor 610 can be driven by an external motor 612. In one embodiment, motor 612 includes a rotatable drive shaft 614 coupled to a cable or pulley system 616. Each rotor 610 may be formed on a rotatable disk or shaft 618 coupled to the pulley system 616, such that rotation of the drive shaft 614 causes rotation of the rotor 610. In some embodiments, a single motor 612 will drive all rotors 610. In other embodiments, the system may include multiple motors, each independently driving one or more rotors 610. Motor 612 may include any suitable motor, such as a brushless DC motor, permanent magnet DC motor, stepper motor, linear motor, synchronous motor, electromagnetic induction motor, servo motor, PMDC brushed motor, shunt motor, series motor, compound motor, etc.

[0183] like Figure 31 As shown, each rotor 610 includes a plurality of individual blades 622 circumferentially spaced around a central hub 624. In one such embodiment, each hub 624 includes five individual blades 622 evenly spaced around the hub; however, it should be appreciated that the blades may include fewer or more than five individual blades. The blades 622 may have the same or different pitch and camber to allow entangled fibers to sequentially untangle or “open” as they pass through the bulk bin 602.

[0184] In an exemplary embodiment, each central hub 624 is positioned such that its blades 622 rotate about an axis tangential to a vertical axis extending through the bulk hopper 602. In the exemplary embodiment, this axis is substantially perpendicular to the vertical axis of the bulk hopper 602. Therefore, as nanoparticle clusters pass downward through the bulk hopper 602, the blades 622 engage these clusters to separate or break them down into smaller nanoparticle clusters / clumps or directly into individual nanoparticles. The blades 622 also serve to force or convey nanoparticles downward through the bulk hopper 602. The bulk hopper 602 may include a single row of rotors 610 or multiple rows of rotors 610.

[0185] Rotors 610 can be configured to rotate in opposite directions, with some hubs 624 rotating counterclockwise and others clockwise. Alternatively, all rotors 610 can rotate in the same direction, i.e., either counterclockwise or clockwise. In an exemplary embodiment, container 602 includes a row of at least four rotors 610 extending substantially parallel to each other across a horizontal axis of container 602, each alternating propeller rotating in the opposite direction to its adjacent propeller, such as... Figure 31 As shown.

[0186] Each central hub 624 of the rotor 610 preferably extends from one side 626 of the bulk hopper 602 to the other side 628 and includes multiple sets of blades 622 extending along its entire length. Each hub 624 may include two or more sets, five or more sets, ten or more sets, twenty or more sets, or forty or more sets of blades extending along its length, depending on the overall dimensions of the bulk hopper 602. Each set of blades is preferably spaced appropriately between each other to ensure that larger nanoparticle agglomerates do not fall between the sets of blades without contacting the blades.

[0187] In some embodiments, hubs 624 are staggered (vertically and / or horizontally) along the width and / or depth of bulk bin 602, such that each set of blades 622 covers a different cross-sectional area inside bulk bin 602. Furthermore, the blades 622 can be designed to overlap each other, such that a set of blades on one hub extends through the gap between two sets of blades on another hub 624. This ensures that nanoparticle clusters located between the two sets of blades contact the blades of the different hubs.

[0188] In one embodiment, container 602 includes a lower rotor 630 primarily used to sweep nanoparticles off the inner wall of bulk hopper 602 to drive them into opening 612. For this purpose, rotor 630 preferably includes at least two rotating blades 632 surrounding a central hub 634. Hub 634 preferably rotates in opposite directions, one hub rotating clockwise and the other counterclockwise, such that rotor 630 can sweep nanoparticles adhering to either side of container 602. Hub 634 preferably extends along an axis substantially perpendicular to the vertical axis of container 602, but it should be recognized that other embodiments are also contemplated. For example, bulk hopper 602 may include a plurality of rotors 630 positioned along the inner wall of bulk hopper 602 to sweep nanoparticles off these walls and drive them toward opening 612.

[0189] like Figure 28 As shown, the collection container 620 has an upper opening coupled to the bulk hopper 602 and a lower opening connected to the lift 604. The lower opening has a much smaller cross-sectional area than the upper opening, allowing the nanoparticles to "leak" downwards to control the flow rate of the nanoparticles through the system, as discussed in more detail below. Furthermore, the container 620 includes one or more mechanisms for conveying or driving the nanoparticles through it. In one embodiment, at least one of these mechanisms includes one or more vibrating elements 638 coupled to the container 620 (see [link to relevant documentation]). Figure 44 The vibrating element 638 is used to convey nanoparticles through container 620 and into elevator 604. The vibrating element is also used to pulse the nanoparticles to break up those nanoparticles that tend to clump together within container 620. This allows the nanoparticles to detach from these clumps and fall into elevator 604.

[0190] The vibrating element may have an amplitude of about 5 to about 500 pounds of force, preferably about 75 to about 250 pounds of force, and may oscillate at a frequency of about 2,000 Hz to about 15,000 Hz, preferably about 7,000 Hz to about 11,000 Hz. The vibrating element may be located on the wall and / or inside the container 620. The vibrating element may be powered by any suitable means. In one embodiment, the vibrating element includes an electromechanical device powered by a DC power supply. The vibrating element converts current into pulses. In another embodiment, the vibrating element is pneumatically driven by compressed air.

[0191] Vibrating element 638 may be coupled to one or more outer walls 639 of collection container 620 (or any other container within feed system 600). In one embodiment, each vibrating element 638 includes one or more attachment elements 641 for attaching oscillator 643 to outer wall 639 and connection elements 645 for coupling vibrating element 638 to a suitable power source. Vibrating element 638 is configured to vibrate the outer wall 639 of collection container to pulse the nanoparticles and break up those nanoparticles that tend to clump together within container 620. This allows the nanoparticles to detach from these clumps and fall into elevator 204.

[0192] Now for reference Figure 28 and Figure 33-35 The lifter 604 is used to elevate nanoparticles exiting the container 620 from a first height to a second height greater than the first height. Nanoparticles are typically not transportable because they have very little or no weight. Therefore, nanoparticles are prone to squeezing together and agglomerating at any type of opening to form clumps. The lifter 604 overcomes these problems by transporting and elevating the nanoparticles from the container 620 to the dispersion system 606.

[0193] In some embodiments, the lift 604 includes one or more delivery tubes 640 for conveying nanoparticles to a higher height without squeezing them back into clumps. In some embodiments, the tube 640 includes at least one segment extending at a transverse angle to the vertical direction (see [link to relevant documentation]). Figure 28 In other embodiments, pipe 640 includes at least one section substantially parallel to the vertical direction (see...). Figure 29 The lift 604 includes a plurality of discs 641 spaced apart from each other throughout the tube 640. The diameter of the discs 641 generally allows the discs 641 to pass through the tube 640 (i.e., slightly smaller than the inner diameter of the tube 640). Furthermore, the diameter of the discs 641 is close enough to the inner diameter of the tube 640 to define internal compartments 642 between adjacent discs 641. As each compartment 642 is conveyed through the tube 640, the discs 641 serve to isolate the interior of the compartment 642.

[0194] A tube 640 extends from a lower opening (not shown) in a collection container 620 to an upper opening 650 in a funnel-shaped delivery container 652 in a dispersion device 606. For reasons discussed below, the container 652 is located above the container 620; therefore, the tube 640 delivers and elevates the nanoparticles from a first height to a second height greater than the first height.

[0195] The elevator 604 also includes a cable 644 within a tube 640, through which compartment 642 is conveyed. In one embodiment, the cable 644 extends through each disc 641 within the tube 640 and is coupled to a suitable power source for moving the cable 644 (and the discs 641 therewith) through the tube. The tube 640 can extend upward from container 620 to the dispersing device 606 and then downward back to container 620 (see [link to relevant documentation]). Figure 28 The upward-moving compartment 642 typically contains nanoparticles, while the downward-moving compartment 642 is substantially free of nanoparticles. Alternatively, the tube 640 may be a continuous tube moving in one direction.

[0196] Refer again Figure 29 The lifting device 604 preferably includes a motor 649 coupled to the cable 644 for pushing the cable 644 through the feeding system 600 in one direction, so that the disc 641 is pushed in that direction. The motor 649 may include any suitable motor, such as a brushless DC motor, a permanent magnet DC motor, a stepper motor, a linear motor, a synchronous motor, an electromagnetic induction motor, a servo motor, a PMDC brushed motor, a shunt motor, a series motor, a compound motor, etc.

[0197] Cable 644 can be coupled to one or more drive wheels that redirect cable 644 within the feeding system 600. For example, as... Figure 29 As shown, cable 644 preferably extends substantially horizontally below bulk hopper 602 and is then reoriented to a vertical direction by first drive wheel 651 to lift nanoparticle agglomerates. Second drive wheel 653 is used to reorient cable 604 to a substantially horizontal direction, wherein cable 604 passes over container 652 to distribute nanoparticles into dispersion system 606.

[0198] The tube 640 includes one or more openings (not shown) aligned with openings in containers 620 and 652 to allow nanoparticles to enter compartment 642 from container 620 and exit compartment 642 into container 652. In some embodiments, the opening located adjacent to container 620 is on the upper surface of tube 640, while the opening located adjacent to container 652 is on the lower surface of tube 640. Alternatively, tube 640 may have a rotatable section allowing the opening to move from one configuration to another. Thus, nanoparticles can fall from container 620 into compartment 642 as a single compartment 642 passes through an opening below container 620. As compartment 642 continues to move upward along tube 642, the inner wall of tube 642 and the disc 641 of compartment 642 seal the interior of compartment 642, trapping the nanoparticles within. This allows the nanoparticles to be transported along the tube without being compressed into bundles or clumps.

[0199] Alternatively, the openings in tube 640 can be opened and closed. For example, lift 604 may include one or more actuators for opening and closing these openings in tube 640. Actuators may include any suitable mechanism, such as electronic actuators, pneumatic actuators, mechanical actuators, etc. In some embodiments, system 600 also includes a controller (not shown) for automatically opening and closing these openings at appropriate times or based on data obtained from sensors (i.e., opening when they pass under container 620 and then closing them as they move upward toward dispersion device 606). In other embodiments, system 600 may be mechanical elements that cooperate with each other to automatically open and / or close the openings as they pass through container 620 and dispersion device 606.

[0200] Figure 36 A cluster 647 of nanoparticles is shown, moved by a lift 604. As shown, each cluster 647 of nanoparticles is located in a compartment 642 between two disks 641 within a tube 640 of the lift 604. As the disks 641 are pushed through the tube 640, the clusters 647 of nanoparticles are moved along with them.

[0201] review Figure 29 The dispersion system 606 is used to control the delivery speed or flow rate of nanoparticles entering the filter media manufacturing system. Specifically, the dispersion system 606 ensures that an appropriate amount of nanoparticles are dispersed onto the fibers within the substrate. For example, the dispersion system 606 is configured to deliver nanoparticles at a specific mass or volumetric flow rate substantially consistent with the rate at which the feeder 200 advances the substrate from upstream to downstream. This ensures that a substantially constant amount of nanoparticles is dispersed throughout the various portions or sub-regions of the substrate, allowing the system to produce a relatively uniform filter media and reducing variability between filter media. The specific rate at which nanoparticles are dispersed into the substrate will depend on the desired specifications of the final filtered product, such as the preferred mass of nanoparticles dispersed in the volume or square area of ​​the filter media. In an exemplary embodiment, nanoparticles are dispersed into the moving substrate at a rate of about 0.1 g / m² to about 10 g / m², but it should be understood that this rate can vary depending on the specifications of the final product.

[0202] The propulsion rate of the substrate will depend on many factors in the manufacturing process, including the desired amount of nanoparticles dispersed into various regions of the substrate. In one embodiment, the propulsion rate of the substrate is from about 0.05 m / s to about 1 m / s.

[0203] The dispersion system 606 typically includes an upper funnel-shaped container 652 for collecting nanoparticles from a conveyor 604, a feed hopper 660, and one or more lower funnel-shaped containers 670. For example... Figure 29 and Figure 37As shown, the upper funnel-shaped container 652 has an upper opening 650 coupled to an opening in a tube 640 of the elevator 604 and a lower opening 655 coupled to a feed hopper 660. The lower opening 655 has a much smaller cross-sectional area than the upper opening 653, allowing the nanoparticles to "leak" downwards to control the flow rate of the nanoparticles through the system. Similar to the collection container 620, the container 652 may also include one or more vibrating elements that pulse the nanoparticles and prevent them from clumping together. These vibrating elements may, for example, be located on the outer wall of the container 652. Alternatively, the vibrating elements may be positioned inside the container 652 to facilitate the transport of nanoparticles through the container 652.

[0204] Now for reference Figure 38 and Figure 39 The feed hopper 660 includes a first opening 661 for receiving nanoparticles from container 652 and a second opening (not shown) for conveying the nanoparticles to lower container 670. The feed hopper 660 also includes one or more mechanisms within the feed hopper 660 for conveying nanoparticles therethrough. The feed hopper 660 preferably includes one or more rotating rollers 662 extending through the interior of the feed hopper 660. One or more rods 663 are coupled to the rollers 662 and configured to rotate with them to sweep nanoparticles downwards through the feed hopper.

[0205] The feed hopper also includes a screw conveyor 664 for moving nanoparticles in a generally horizontal direction through the feed hopper 660 to the lower container 670. In a preferred embodiment, the screw conveyor 664 includes a plurality of curved blades 665 for receiving clusters of nanoparticles that have fallen vertically into the feed hopper 660 and redirecting these nanoparticles horizontally through the feed hopper 660. The curved blades 665 also control the volumetric flow rate of the nanoparticles through the feed hopper 660 and into the filter manufacturing system. The screw conveyor 664 can be driven by any suitable motor 666, such as any of the motors described above.

[0206] Now for reference Figure 43 The lower container 670 has an upper opening 672 coupled to an opening in the feed hopper 660 and a lower opening 676 coupled to the aforementioned fiber manufacturing system. The lower container 670 preferably has a substantially funnel-shaped form, such that the lower opening has a smaller cross-sectional area than the upper opening, to control the flow rate of nanoparticles through it. Similar to the collection container 620, the lower container 670 may include one or more vibrating elements that pulse the nanoparticles and prevent them from forming clumps. These vibrating elements may, for example, be located within the inner wall of the container 670. Alternatively, the vibrating elements may be positioned to facilitate the transport of nanoparticles through the container 670.

[0207] Now for reference Figure 42The feed system 600 may further include a fine-tuning flow control device 680, which receives nanoparticles from container 670 and provides final control over the volumetric flow rate of the nanoparticles entering the filter manufacturing apparatus. The flow control device 680 includes a funnel-shaped container 682 having an opening 684 for receiving nanoparticles from container 670 and a lower opening (not shown) coupled to a feeder tray 690. The feeder tray 690 includes a feed channel 692 that tapers towards the opening 693. The opening 693 may be coupled to any suitable filter media manufacturing apparatus, such as any of the filter media manufacturing apparatuses described above, or other filter media manufacturing apparatuses that may be conceived by those skilled in the art.

[0208] Example 1 Synthetic nanoparticles (microfibers (0.5 μm in diameter and 100 μm in length)) were dispersed onto a fiber-based substrate (labeled “nano” in Table 1) that had undergone wet web forming and calendering using the system and methods described above. The substrate and nanoparticles were then calendered. During calendering, the microfibers were thermally bonded to the fibers in the substrate at a temperature of 243°F for 3, 4, and 5 seconds (labeled as 243F 3 s, 4 s, and 5 s, respectively, in Table 1). Figures 46A-46C are microscopic images of high-density polyethylene (HDPE) nanoparticles dispersed onto a substrate containing a fiber combing medium as described herein.

[0209] Fiber substrates (wet-laid and calendered) without nanoparticle dispersion were also produced as a control (labeled "Nano-free" in Table 1). The first nano-free sample was tested "as is" without heating or calendering the substrate. A second nano-free sample was tested after heating and calendering or pressing the substrate at 243 degrees Fahrenheit. The applicant also compared the specifications of meltblown equivalent grade substrates (without nanoparticles) with several meltblown fiber substrates containing nanoparticles (labeled meltblown equivalent). The applicant measured the average and maximum flow orifice diameters in micrometers, and the bubble point in (in / h20). As mentioned above, the bubble point (pressure) is the amount of force required to allow liquid to pass through the substrate (i.e., the higher the value, the more difficult it is to allow liquid to pass through the substrate). The results of this test are shown in Table 1 below.

[0210] Table 1 As shown in the table above, heating and pressing the nanoparticle-free sample had minimal effect on the maximum and average flow pore sizes, reducing them from 41.76 μm to 36.65 μm and from 27.4 μm to 24.36 μm, respectively. The average and maximum flow pore sizes of the nanoparticle-bound substrates were significantly smaller than those of the nanoparticle-free samples. Specifically, the average flow pore size of the nanoparticle-bound substrates was at least 75% smaller than that of the nanoparticle-free substrates, i.e., 6.71 μm, 3.88 μm, and 3.4 μm, respectively. The average flow pore size of the latter substrate (3.4 μm) is essentially equal to the meltblown equivalent size (3.3 μm). This indicates that the system and method described herein provide a filter medium with a significantly reduced average flow pore size, which improves the efficiency of the filter in capturing contaminants.

[0211] The maximum flow pore size also decreased after using nanoparticles. As shown above, the maximum flow pore sizes of the substrates with nanoparticles were 34.68 μm, 21.32 μm, and 15.8 μm. Specifically, the maximum flow pore size of the substrate thermally bonded for 5 seconds was less than half that of the substrate without nanoparticles, even after two heating steps were performed on the sample.

[0212] Furthermore, the bubble point (pressure) of the substrate incorporating nanoparticles is substantially lower than that of the meltblown equivalent substrate (without nanoparticles). The bubble point using nanoparticles is at least 50% lower than that without nanoparticles. In some cases, the bubble point using nanoparticles is 67% lower than that without. This indicates that the systems and methods described herein provide filter media with significantly reduced bubble points, which improves the liquid flux through the filter.

[0213] While the apparatus, system, and method have been described in detail herein with respect to certain preferred embodiments, many modifications and variations can be made therein by those skilled in the art. Therefore, the above description should not be construed as limiting, but rather as including such obvious variations as described above, and is limited only by the spirit and scope of the appended claims.

[0214] For example, in a first aspect, a first embodiment includes: a substrate comprising one or more fibers and having a first surface and an opposing second surface; and a plurality of nanoparticles disposed within the substrate between at least the first and second surfaces. At least some of the nanoparticles are bonded to at least some of the fibers in the substrate.

[0215] The second embodiment is the first embodiment, wherein at least some of the nanoparticles are thermally bonded to at least some of the fibers.

[0216] The third embodiment is any combination of the first two embodiments, and further includes an adhesive within the substrate that retains at least some of the nanoparticles onto at least some of the fibers.

[0217] The fourth embodiment is any combination of the first three embodiments, wherein the adhesive comprises an insoluble adhesive.

[0218] The fifth embodiment is any combination of the first four embodiments, wherein the size of at least one dimension of the nanoparticle is less than about 20 micrometers.

[0219] The sixth embodiment is any combination of the first five embodiments, wherein the size of at least one dimension of the nanoparticle is less than about 1 micrometer.

[0220] The seventh embodiment is any combination of the first six embodiments, wherein the nanoparticles comprise microfibers with a size of about 1 micrometer to about 20 micrometers in at least one dimension.

[0221] The eighth embodiment is any combination of the first seven embodiments, wherein the microfiber has at least one dimension with a size of about 5 micrometers.

[0222] The ninth embodiment is any combination of the first eight embodiments, wherein the microfibers have a length of about 100 micrometers to about 600 micrometers.

[0223] The 10th embodiment is any combination of the first nine embodiments, wherein the microfiber is selected from the group consisting of: metal fibers, carbon fibers, polypropylene (PP), nylon fibers, polybutene (PBT), ethylene polyester (PET), polylactic acid (PLA), polyamide (PA), glass, biosoluble glass, ceramic materials, acrylics, polyethylene, high-density polyethylene (HDPE), low-density polyethylene (LDPE), and combinations thereof.

[0224] The 11th embodiment is any combination of the first 10 embodiments, wherein the substrate comprises a porous membrane.

[0225] The 12th embodiment is any combination of the first 11 embodiments, wherein the average flow pore size of the filter medium is less than about 10 micrometers.

[0226] The 13th embodiment is any combination of the first 12 embodiments, wherein the average flow aperture is less than about 4 micrometers.

[0227] The 14th embodiment is any combination of the first 13 embodiments, wherein the bubble point of the filter medium is less than about 20 in / h20.

[0228] The 15th embodiment is any combination of the first 14 embodiments, wherein the bubble point is less than about 15 in / h20.

[0229] The 16th embodiment is any combination of the first 15 embodiments, wherein the fiber includes bio-component fibers.

[0230] The 17th embodiment is any combination of the first 16 embodiments, wherein the fibers in the substrate are bonded together by thermal bonding, ultrasonic bonding, cellulose wet web forming, glass wet web forming, synthetic wet web forming, composite wet web forming, needle punching, meltblowing, air-blowing, spunbonding, and combinations thereof.

[0231] The 18th embodiment is any combination of the first 17 embodiments, wherein the fibers are hydroentangled.

[0232] The 19th embodiment is any combination of the preceding 18 embodiments, wherein the fiber substrate comprises polyolefins, polyesters, polyethylene (PE), polypropylene (PP), blends of PP and PE, PBT, PET, CoPET, PLA, PA, PHB, PVOH, polyamides, and combinations thereof.

[0233] The 20th embodiment is any combination of the first 19 embodiments, wherein the areal density of the nanoparticles decreases from the first surface to the second surface.

[0234] The 21st embodiment is any combination of the first 20 embodiments, wherein the fiber substrate has a thickness from a first surface to a second surface, and wherein the nanoparticles are arranged within the substrate at a thickness of at least 25% of the thickness from the first surface to the second surface.

[0235] The 22nd embodiment is any combination of the preceding 21 embodiments, wherein the nanoparticles are arranged within the fiber substrate at a thickness of at least 50% from the first surface to the second surface.

[0236] The 23rd embodiment is any combination of the first 22 embodiments, wherein the nanoparticles are generated in a gas and dispersed through a first surface of the fiber substrate.

[0237] The 24th embodiment is any combination of the first 23 embodiments, wherein the nanoparticles are arranged within the fiber substrate from the first surface to the second surface.

[0238] The 25th embodiment is any combination of the first 24 embodiments, wherein the areal density of the nanoparticles at the midpoint between the first surface and the second surface is about 25% of the areal density of the nanoparticles at the first surface.

[0239] The 26th embodiment is any combination of the first 25 embodiments, wherein the areal density of the nanoparticles at the second surface is about 50% of the areal density of the nanoparticles at the first surface.

[0240] On the other hand, a liquid filter is provided that includes any combination of the first 26 embodiments.

[0241] In another embodiment, a first embodiment is provided, comprising: a housing including an inlet for receiving liquid and an outlet for discharging liquid; and a filter medium disposed within the housing between the inlet and the outlet. The filter medium comprises one or more fibers and has a first surface and opposing second surfaces, and a plurality of nanoparticles disposed within the filter medium between at least the first surface and the second surface. At least some of the nanoparticles are bonded to at least some of the fibers in the filter medium.

[0242] The second embodiment is the first embodiment, wherein the average flow pore size of the filter medium is less than about 10 micrometers.

[0243] The third embodiment is any combination of the first two embodiments, wherein the average flow aperture is less than about 4 micrometers.

[0244] The fourth embodiment is any combination of the first three embodiments, wherein the ratio of the maximum flow orifice diameter to the average flow orifice diameter is less than about 10.

[0245] The fifth implementation is any combination of the first five implementations, wherein the ratio is less than about 6.

[0246] The sixth embodiment is any combination of the first five embodiments, wherein the bubble point of the filter medium is less than about 20 in / h20.

[0247] The seventh embodiment is any combination of the first six embodiments, wherein the bubble point is less than about 15 in / h20.

[0248] The eighth embodiment is any combination of the first seven embodiments, wherein the filter medium further includes a support layer.

[0249] The ninth embodiment is any combination of the first eight embodiments, wherein at least some of the nanoparticles are thermally bonded to at least some of the fibers.

[0250] The tenth embodiment is any combination of the first nine embodiments, and further includes an adhesive within the substrate that retains at least some of the nanoparticles onto at least some of the fibers.

[0251] The 11th embodiment is any combination of the first 10 embodiments, wherein the adhesive comprises an insoluble adhesive.

[0252] The 12th embodiment is any combination of the first 11 embodiments, wherein the size of at least one dimension of the nanoparticle is less than about 20 micrometers.

[0253] The 13th embodiment is any combination of the first 12 embodiments, wherein the size of at least one dimension of the nanoparticle is less than about 1 micrometer.

[0254] The 14th embodiment is any combination of the first 13 embodiments, wherein the nanoparticles comprise microfibers with a size of about 1 micrometer to about 20 micrometers in at least one dimension.

[0255] The 15th embodiment is any combination of the first 14 embodiments, wherein at least one flavor of the microfiber has a size of about 5 micrometers.

[0256] The 16th embodiment is any combination of the preceding 15 embodiments, wherein the microfibers are selected from the group consisting of: metal fibers, carbon fibers, polypropylene (PP), nylon fibers, polybutene (PBT), ethylene polyester (PET), polylactic acid (PLA), polyamide (PA), glass, biosoluble glass, ceramic materials, acrylics, polyethylene, high-density polyethylene (HDPE), low-density polyethylene (LDPE), and combinations thereof.

[0257] The 17th embodiment is any combination of the preceding 16 embodiments, wherein the fiber substrate comprises polyolefins, polyesters, polyethylene (PE), polypropylene (PP), blends of PP and PE, PBT, PET, CoPET, PLA, PA, PHB, PVOH, polyamides, and combinations thereof.

[0258] On the other hand, an intake filter is provided that includes any combination of the first 17 embodiments.

[0259] On the other hand, a plate filter is provided that includes any combination of the first 17 embodiments.

[0260] On the other hand, a filter press is provided that includes any combination of the first 17 embodiments.

[0261] On the other hand, a rotary drum filter is provided, which includes any combination of the first 17 embodiments.

[0262] On the other hand, a fuel filter is provided that includes any combination of the first 17 embodiments.

[0263] On the other hand, a semiconductor processing filter is provided, which includes any combination of the first 17 embodiments.

[0264] On the other hand, a pipeline filter is provided that includes any combination of the first 17 embodiments.

[0265] On the other hand, a wastewater filter is provided that includes any combination of the first 17 embodiments.

[0266] On the other hand, a microfiltration membrane is provided, which includes any combination of the first 17 embodiments.

[0267] On the other hand, a water filter is provided that includes any combination of the first 17 embodiments.

[0268] On the other hand, a hydraulic filter is provided that includes any combination of the first 17 embodiments.

[0269] On the other hand, a metal filter is provided that includes any combination of the first 17 embodiments.

Claims

1. A filter medium for a liquid filter, the filter medium comprising: A substrate comprising one or more fibers and having a first surface and an opposing second surface; as well as A plurality of nanoparticles are disposed within the substrate between at least a first surface and a second surface, wherein at least some of the nanoparticles are bonded to at least some of the fibers in the substrate.

2. The filter medium according to claim 1, wherein at least some of the nanoparticles are thermally bonded to at least some of the fibers.

3. The filter medium of claim 1 further comprises an adhesive within the substrate, the adhesive retaining at least some of the nanoparticles onto at least some of the fibers.

4. The filter medium according to claim 3, wherein the adhesive comprises an insoluble adhesive.

5. The filter medium according to claim 1, wherein the nanoparticles have a size of less than about 20 micrometers in at least one dimension.

6. The filter medium according to claim 1, wherein the nanoparticles have at least one dimension with a size of less than about 1 micrometer.

7. The filter medium according to claim 1, wherein the nanoparticles comprise at least one microfiber having a dimension of about 1 micrometer to about 20 micrometers.

8. The filter medium according to claim 7, wherein the microfiber has at least one dimension having a size of about 5 micrometers.

9. The filter medium according to claim 7, wherein the microfibers have a length of about 100 micrometers to about 600 micrometers.

10. The filter medium according to claim 7, wherein the microfibers are selected from the group consisting of: metal fibers, carbon fibers, polypropylene (PP), nylon fibers, polybutene (PBT), ethylene polyester (PET), polylactic acid (PLA), polyamide (PA), glass, biosoluble glass, ceramic materials, acrylics, polyethylene, high-density polyethylene (HDPE), low-density polyethylene (LDPE), and combinations thereof.

11. The filter medium according to claim 1, wherein the substrate comprises a porous membrane.

12. The filter medium according to claim 1, wherein the average flow pore size of the filter medium is less than about 10 micrometers.

13. The filter medium according to claim 12, wherein the average flow pore size is less than about 4 micrometers.

14. The filter medium according to claim 1, wherein the bubble point of the filter medium is less than about 20 in / h20.

15. The filter medium of claim 14, wherein the bubble point is less than about 15 in / h20.

16. The filter medium according to claim 1, wherein the fiber comprises biological component fiber.

17. The filter medium according to claim 1, wherein the fibers in the substrate are bonded together by means of thermal bonding, ultrasonic bonding, cellulose wet web forming, glass wet web forming, synthetic wet web forming, composite wet web forming, needle punching, melt blowing, air-blowing, spunbonding, and combinations thereof.

18. The filter medium according to claim 1, wherein the fibers are wet-laid.

19. The filter medium according to claim 1, wherein the fibers in the substrate are selected from the group consisting substantially of: polyolefins, polyesters, polyethylene (PE), polypropylene (PP), blends of PP and PE, PBT, PET, CoPET, PLA, PA, PHB, PVOH, polyamides, and combinations thereof.

20. The filter medium according to claim 1, wherein the fiber is a bio-component fiber comprising CoPET / PET or HDPE / PET.

21. The filter medium of claim 1, wherein the substrate has a thickness from a first surface to a second surface, wherein the nanoparticles are arranged within the substrate at a thickness of at least 25% of the thickness from the first surface to the second surface.

22. The filter medium of claim 1, wherein the nanoparticles are arranged within the fiber substrate at a thickness of at least 50% from the first surface to the second surface.

23. The filter medium of claim 1, wherein the nanoparticles are arranged within a fiber substrate extending from the first surface to the second surface.

24. The filter medium according to claim 1, wherein the nanoparticles are generated in the gas and dispersed through a first surface of the fiber substrate.

25. A liquid filter comprising the filter medium of claim 1.

26. A liquid filter, comprising: A housing, the housing including an inlet for receiving liquid and an outlet for discharging liquid; as well as A filter medium, disposed within the housing between the inlet and the outlet, comprises: A substrate comprising one or more fibers and having a first surface and an opposing second surface; as well as Multiple nanoparticles are arranged between at least a first surface and a second surface within the substrate, wherein the average flow pore size of the filter medium is less than about 10 micrometers.

27. The filter of claim 26, wherein the average flow pore size is less than about 4 micrometers.

28. The filter of claim 26, wherein the ratio of the maximum flow orifice diameter to the average flow orifice diameter is less than about 10.

29. The filter of claim 28, wherein the ratio is less than about 6.

30. The filter of claim 26, wherein the bubble point of the filter medium is less than about 20 in / h20.

31. The filter of claim 30, wherein the bubble point is less than about 15 in / h20.

32. The filter of claim 26, wherein the filter medium further comprises a support layer.

33. The filter of claim 26, wherein at least some of the nanoparticles are thermally bonded to at least some of the fibers.

34. The filter of claim 26 further comprises an adhesive within the substrate, the adhesive retaining at least some of the nanoparticles onto at least some of the fibers.

35. The filter of claim 34, wherein the adhesive comprises an insoluble adhesive.

36. The filter of claim 26, wherein the nanoparticles have at least one dimension with a size of less than about 20 micrometers.

37. The filter of claim 26, wherein the nanoparticles have at least one dimension with a size of less than about 1 micrometer.

38. The filter of claim 26, wherein the nanoparticles comprise at least one microfiber having a dimension of about 1 micrometer to about 20 micrometers.

39. The filter of claim 38, wherein at least one dimension of the microfiber has a size of about 5 micrometers.

40. The filter of claim 38, wherein the microfibers are selected from the group consisting of: metal fibers, carbon fibers, polypropylene (PP), nylon fibers, polybutene (PBT), ethylene polyester (PET), polylactic acid (PLA), polyamide (PA), glass, biosoluble glass, ceramic materials, acrylics, polyethylene, high-density polyethylene (HDPE), low-density polyethylene (LDPE), and combinations thereof.

41. The filter of claim 26, wherein the substrate comprises a porous membrane.

42. The filter of claim 26, wherein the liquid filter is a depth filter.

43. The filter of claim 26, wherein the housing comprises a cylinder.

44. The filter of claim 26, wherein the housing comprises a bag.

45. The filter of claim 26, wherein the housing comprises a centrifuge.

46. ​​The filter of claim 26, wherein the liquid filter includes an air intake filter.

47. The filter of claim 26, wherein the liquid filter comprises a plate filter.

48. The filter of claim 26, wherein the liquid filter comprises a filter press.

49. The filter of claim 26, wherein the liquid filter comprises a rotary drum filter.

50. The filter of claim 26, wherein the liquid filter comprises a fuel filter.

51. The filter of claim 26, wherein the liquid filter comprises a semiconductor processing filter.

52. The filter of claim 26, wherein the liquid filter comprises a pipeline filter.

53. The filter of claim 26, wherein the liquid filter comprises a wastewater filter.

54. The filter of claim 26, wherein the liquid filter comprises a microfiltration membrane.

55. The filter of claim 26, wherein the liquid filter comprises a water filter.

56. The filter of claim 26, wherein the liquid filter comprises a hydraulic filter.

57. The filter of claim 26, wherein the liquid filter comprises a metal filter.

58. The filter of claim 26, wherein the liquid filter comprises a battery separator.

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