Patent Application
20240052457
N/A.
The present invention generally relates to systems, devices, and methods for separating various materials.
Fluid based separations of ions, molecules, and ultrafine particles is important to many technologies including large-scale commercial applications, such as desalination, metal separation, chemical separations, and water purification, as well as smaller niche applications in isotope separation and fine particle removal. For example, ion separation technologies are important to the separation and recovery of metals in commercial metal recovery and purification processes. Molecular separations, such as the separation of hydrocarbons, are performed on very large scales commercially. Isotopes are critical to a variety of applications including physical science analyses, biology, medicine, pharmaceuticals, and national security, and their accurate separation is critical to their niche uses. Ultrafine particle removal is very important to many industries in which contamination is detrimental to performance.
Additionally, the continuous availability of fresh water is one of the main factors in sustainable development in many regions of the world. Many water resources have been utilized to their full potential in arid regions, and growth in many of these regions is limited by water availability. In some cases, the rate of evaporation of freshwater resources concentrates salts, making it difficult to utilize some available resources. In order to address this need for water in such regions, desalination has become a common practice, but it is relatively expensive, and it consumes a significant amount of energy. Improvements in desalination technology and a reduction in associated costs have the potential to improve water resources by making desalination more economically and technically feasible. It has been reported that almost half as many desalination plants were built in the period of 2000-2010 as were those built in the preceding three decades. This indicates that a limited number of facilities use thermal (evaporation) methods and reverse osmosis (RO). However, other processes are membrane based. Some of these processes are nanofiltration (NF), seawater RO (SWRO), brackish water RO (BWRO), and electrodialysis reversal (EDR). These plants are further categorized as potable water, water for disposal or recycle, and facility aquifer recharge.
The municipal desalination industry is transitioning toward high recovery processing, known as volume reduction or concentrate minimization. Water reuse, or water that has been reclaimed through wastewater treatment, but may not be suitable for core household or domestic use, can also fulfill a need by providing supply for irrigation or industrial users.
In most arid locations, the most widely used effective separation technology for desalination is reverse osmosis. However, the requirement of high pressures and frequent replacement of membrane modules is challenging. Thus, there are opportunities to improve the efficiency and to reduce the cost of desalination.
However, current separation techniques utilize relatively expensive equipment, have generally small separation coefficients thereby requiring cascades of separation units to achieve needed product purity levels, utilize one method or force to facilitate separation, are slow, limited to the separation of two entities, require elevated pressures and membranes that are subject to plugging, and/or are not tunable for effective separation of multiple constituents from a stream containing more than two entities. Further, some separation processes (e.g., distillation) require large inputs of energy to change the state of molecules undergoing separation. Additionally, many isotope separation technologies utilize gas-based separations, which require chemical and state conversion to gaseous compounds that are typically toxic and often corrosive followed by conversion back to useable forms such as metals or ions.
Similarly, with regards to isotopes, appropriate separations are critical. In most cases isotopes must be relatively pure or highly enriched before they become useful. Current isotope separation technologies are relatively inefficient, capital and labor intensive, and often produced by a limited number of nondomestic suppliers. Most isotopes are produced by separating naturally occurring isotopes or through nuclear reaction, followed by separation as needed. The separation of naturally occurring isotopes is usually performed using gas centrifuge technology, electromagnetic methods, diffusion processes, distillation, ion chromatography, or ion exchange chromatography. Many common isotopes of carbon, oxygen and boron are produced by distillation, chemical exchange, and thermal diffusion. Isotopes can also be enriched by contacting a feed solution containing the isotopes with a cyclic polyether wherein a complex of one isotope is formed with the cyclic polyether, the cyclic polyether complex can be extracted from the feed solution, and the isotope can be subsequently separated from the cyclic polyether. Intermetallic compounds with a CaCu5 type of crystal structure, particularly LaNiCo and CaNi5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation column. The inclusion of an inert metal to dilute the hydride improves performance of the column. A large-scale multi-stage chromatographic separation process run as a secondary process off a hydrogen feed stream from an industrial plant which uses large volumes of hydrogen can produce large quantities of heavy water at an effective cost for use in heavy water reactors.
Many of the stable isotopes used domestically are in short supply or unavailable for future research and applications. Examples of such include, but are not limited to 157Gd, 76Ge, 204pb, 96Ru, 150Sm, 181Ta, 180W, and 51V. These isotopes are useful in a variety of applications including neutron capture therapy, toxicology, accelerator target and cross-section measurements, solid state NMR, and other areas of research. Boron-10 has a natural abundance of ˜20% and the rest, 80%, is Boron-11. 10B is used in control rods of nuclear reactors, breeder-reactors, and other safety devices. It is mainly enriched using a multistage exchange-distillation method where boron trifluoride-dimethyl ether complex is used. Isotope fractionation is achieved through complex distillation at reduced pressure in a tapered columns (cascade). Note that the B-11 enrichment system is a gas-fluid exchange system and involves complex purification processing. The alkaline earth metal strontium (38Sr) has four stable naturally occurring isotopes: 84Sr (0.56%), 86Sr (9.86%), 87Sr (7.0%) and 88Sr (82.58%). Its standard atomic weight is 87.62. Some of the important separation methods include use of chloroform solutions with dicyclohexano-18-crown-6, ion exchange resin for sorption of strontium and solubility-based separation (using nitric acid), and precipitation of strontium sulfate. Magnesium isotopes are separated using novel N3O2 azo-crown ion exchanger. Such existing chemical ion exchange techniques resulted in separation factors of 1.030, 1.009, and 1.027 for 24mg-25mg, 25mg-26mg, and 24Mg-26Mg combinations, respectively. Zone melting has also been applied for separation of magnesium isotopes. In such a case the coefficient of separation was ˜1.006. Magnesium isotope separation has also been performed using hydrous manganese (IV) oxide. Vacuum arc-based centrifugation has also been used for Mg isotope enrichment. The present invention describes simplified techniques that can achieve similar or even better separation factors, at relatively low cost, and fast processing time.
Boron has two stable isotopes. The isotopic mass of 11B is 11.009, whereas isotopic mass 10B is 10.012. The spin and parity of these isotopes are different: 11B has 3/2—whereas 11B has 3+. Similarly, calcium also has several stable isotopes (40Ca, 42ca , 43Ca , 44Ca and 46Ca) and other useful radioactive isotopes. Among calcium isotopes, the highest proportion among them was for 40Ca (˜96.94%) followed by 44Ca (˜2.08%). Naturally occurring iron (26Fe) consists of four stable isotopes: 5.845% of 54Fe (possibly radioactive with a half-life over 4.4×1020 years), 91.754% of 56Fe, 2.119% of 57Fe and 0.286% of 58Fe. The isotope 56Fe is the isotope with the lowest mass per nucleon, 930.412 MeV/c2, though not the isotope with the highest nuclear binding energy per nucleon, which is nickel-62. However, because of the details of how nucleosynthesis works, 56Fe is a more common endpoint of fusion chains inside extremely massive stars and is therefore more common in the universe, relative to other metals, including 62Ni, 58Fe and 60Ni, all of which have a very high binding energy. The isotope 57Fe is widely used in Mossbauer spectroscopy and the related nuclear resonance vibrational spectroscopy due to the low natural variation in energy of the 14.4 keV nuclear transition. 58Fe is both naturally occurring and can be produced by fission. It has special application in research to develop successful interventions for anemia, conditions for effective iron absorption and excretion, metabolic tracer studies to identify genetic iron control mechanisms, and energy expenditure studies. Naturally occurring gadolinium (64 Gd) is composed of 6 stable isotopes, 154Gd, 155Gd, 156Gd, 157Gd, 158Gd and 160Gd. Copper has two stable isotopes, 63Cu and 65Cu. Naturally occurring zirconium (40 Zr) is composed of four stable isotopes (of which one may in the future be found radioactive), and one very long-lived radioisotope (96Zr), a primordial nuclide that decays via double beta decay with an observed half-life of 2.0×1019 years.
In the metals processing industry there is a need to separate iron and other dissolved elements, and/or ultrafine particles from solutions. There is also a need in the metals industry to concentrate desired elements or fine particles in processing streams. The presently described separator devices, systems and methods could help to accomplish this due to differences in ion, molecule, and particle properties that can be used as the basis for separation by the forces discussed herein.
In critical materials processing, there is a need to separate elements with similar properties as well as a need to separate elements or ions with different properties. The separator devices, systems and methods discussed herein can facilitate low cost separations for such scenarios. Examples include separating individual rare earth elements by differences in magnetic properties, electrostatic properties, or density. Another example is separating lithium from cobalt or manganese in battery material processing.
Removal of contaminants such as metal ions from water or organic contaminants from blood could be performed using the devices, systems and methods discussed herein.
In an embodiment, a thin fluid layers and streams facilitated, force-based, ion, molecule, and fine particle separator is disclosed. The separator includes at least one support having a surface and defining one or more holes, channels, tubes, or small stream pathways or including one or more collection apparatuses therein. The at least one support includes at least one inclined surface, at least one rotatable cylinder, or at least one channel, tube or small stream pathway. The separator also includes a fluid source that is configured to hold a fluid that includes one or more entities therein. The fluid source is configured to apply a fluid to the surface of the at least one support, channel, tube, etc. The fluid may be dispensed to the surface, channel, tube or small stream pathway or collection thereof during operation, wherein the separator and its surface channels, tubes or small stream pathways are configured and utilized to form a thin fluid layer or stream or sets thereof. The thin fluid layers or streams separator also includes at least one force application device configured to apply a force to a portion of the thin fluid layer or stream or sets thereof, the force including at least one of a centrifugal force, a magnetic force, an electrical force, an electrostatic force, an electrolytic force, a hydrophobic force, a hydrophilic force, or a concentration gradient.
In an exemplary embodiment, a thin fluid layers or streams-based separation device is used for separating atoms, ions, isotopes, molecules or other fine particles from one another. Such a device includes at least one support having a surface, the at least one support including at least one inclined surface, at least one rotatable cylinder, or a channel or collection of channels or fluid pathways. A fluid source is provided, configured to hold a fluid that includes one or more entities to be separated therein, the fluid source being configured to apply a fluid to the surface of the at least one support, wherein the separator is configured to form one or more thin fluid layers or streams on the surface after receiving the fluid from the fluid source. The device also includes at least one force application device configured to apply a desired force to at least a portion of the supported thin fluid layers or streams, the force including at least one of a centrifugal force, a magnetic force, an electric or electrostatic force, an electrolytic force, a concentration gradient, a hydrophobic force or a hydrophilic force. The device also includes one or more collection devices, channels, tubes, or layers positioned to receive fluid enriched or depleted in atoms, ions, isotopes molecules, or other fine particles of the entities to be separated, leaving the region in which the desired force is applied.
A related method for separating atoms, ions, isotopes, molecules, or other fine particles includes providing a separation device as described, and using the thin fluid layers or streams-based separation device to separate select atoms, ions, isotopes, molecules, or fine particles of the entities within the fluid source.
In any of the described embodiments, the at least one support defines one or more holes, channels, tubes or layers therein and the one or more collection devices are positioned adjacent to the one or more holes, channels, tubes, or layers.
In any of the described embodiments, the at least one support includes the at least one rotatable cylinder, wherein rotating the at least one rotatable cylinder with the at least one force application device causes the centrifugal force to be applied to the thin fluid layers or streams.
In any of the described embodiments, the at least one support includes the at least one inclined surface.
In any of the described embodiments, a thickness of the thin fluid layers or streams is selected or controlled by controlling at least one of a flow rate of the fluid dispensed from the fluid source, a viscosity of the fluid, a thickness of one or more thin porous layers or sets of channels, tubes, or streams disposed on the surface, selected properties of the one or more thin porous layers or sets of channels, tubes, or streams, an angle of incline of the surface, a length of the surface, or an angular velocity at which the surface rotates.
In any of the described embodiments, one or more thin porous layers may be disposed on the surface, configured to reduce flow turbulence.
In any of the described embodiments, any such thin porous layers may include chromatography or hydrophilic/hydrophobic separation materials.
In any of the described embodiments, the at least one force application device includes one or more magnets that are configured to apply a magnetic field to the thin fluid layers or streams.
In any of the described embodiments, the at least one force application device includes one or more electrodes configured to apply an electric or electrostatic field to the thin fluid layers or streams.
In any of the described embodiments, the at least one force application device includes one or more electrodes positioned to directly contact the thin fluid layer or stream.
In any of the described embodiments, the at least one force application device includes one or more sequential ring electrodes.
In any of the described embodiments, the at least one force application device is configured to apply an oscillating force.
In any of the described embodiments, the at least one force application device includes at least one carrier or solvent inlet configured to contact the at least one solvent or carrier with the fluid to form a concentration gradient.
In any of the described embodiments, a system may be provided, that includes a plurality of separators, wherein each of the plurality of separators are positioned in cascading sequence to optimize separation of specific entities in the fluid source.
In any of the described embodiments, the fluid can be a liquid or a gas.
In any of the described embodiments, the at least one force application device can include: one or more magnets that are configured to apply the magnetic field to the thin liquid film; one or more electrodes configured to apply the electric or electrostatic field to the thin liquid film; one or more electrodes positioned to directly contact the thin liquid film; one or more sequential ring electrodes; wherein the at least one force application device is configured to apply an oscillating force; or wherein the at least one force application device includes at least one carrier or solvent inlet configured to contact at least one solvent or carrier with the liquid to form a concentration gradient.
In any of the described embodiments, the residence time associated with the presently described separation devices may be relatively short, e.g., no more than about 5 minutes, no more than about 3 minutes, no more than about 1 minute, no more than about 30 seconds, no more than about 10 seconds, no more than about 5 seconds, or no more than about 3 seconds.
In any of the described embodiments, the presently described separation devices may achieve a separation coefficient of at least 1.001, 1.002, 1.003, 1.004, 1.005, 1.006, 1.007, 1.008, 1.009, 1.01, 1.015, 1.02, 1.025, 1.03, 1.035, 1.04, 1.045, 1.05, 1.055, 1.06, 1.065, 1.07, 1.075, 1.08, 1.085, 1.09, 1.095, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.0 or greater in short duration, single pass fluid pass separators or much greater in cascading, multiple pass fluid separators, or separator systems. As the working examples show, significant separation can be quickly achieved using the presently described devices, systems, and methods, even for perceivably difficult separations (e.g., separation of isotopes or other entities where mass or other differences are quite small).
Features from any of the disclosed embodiments may be used in combination with one another, without limitation. In addition, other features and advantages of the present disclosure will become apparent to those of ordinary skill in the art through consideration of the following detailed description and the accompanying drawings.
Various objects, features, characteristics, and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings and the appended claims, all of which form a part of this specification. In the figures, like reference numerals may be utilized to designate corresponding or similar parts in the various figures, and the various elements depicted are not necessarily drawn to scale.
The present disclosure describes separators that employ thin fluid layers or streams that are configured to utilize such thin fluid layers or streams, multi-port collections, and, when appropriate, one or more forces to separate and recover elements, molecules, ions, isotopes, and/or particles (“entities”) in diverse applications using a variety of forces. The thin fluid layers or streams separators disclosed herein include at least one support having a surface. The at least one support may include an inclined surface (e.g., inclined flat plate(s)), one or more rotatable cylinders (e.g., centrifugal devices), or one or more channels, collections of channels, or fluid pathways, e.g., channels, streams, tubes or a hollowed structure (e.g., a pipe). The fluid separators may allow for the creation of a thin fluid flowing layer or stream or sets of the same on the surface of the support by dispensing a fluid onto the surface, channels, tubes, or sets thereof. The fluid dispensed onto the surface, channels, tubes, or sets thereof, and by extension the thin fluid layer or stream itself, may include entities with different properties that can be separated based on differences in those properties such as density, charge, conductivity, mobility, hydrophobicity/hydrophilicity, polarity, electrochemical potential, size, mass, etc. Depending on the properties of the entities to be separated, the thin fluid layers or streams separators disclosed herein can include at least one force application device configured to subject at least a portion of the thin fluid layer(s) or stream(s) to a large force gradient using at least one of a magnetic force, an electric and/or electrostatic force, a centrifugal force, an electrolytic force, an oscillating force, a concentration gradient, or a hydrophobic force or a hydrophilic force. In an example, the thin fluid layers or streams separator may form the thin fluid layers or streams due to the force (e.g., centrifugal force) applied to the fluid on the surface of the support and/or at least one thin porous layer or sets of channels, tubes, or streams that is disposed on the surface of the support. Such thin fluid layers or streams separators may have short residence times for separation (e.g., less than 30 seconds), and in some cases can efficiently separate more dense metal ions, metal bearing compounds, or isotopes from lighter ones. The separators disclosed herein may also include one or more collection devices to collect separated or partially separated products. Such separators may be operated in series, to further enhance the separation.
In an embodiment, the separators may include one or more thin porous layers or sets of channels, tubes, or streams layers or streams disposed on the surface of the at least one support comprising one or more fibers that are configured to contain the fluid and prevent or minimize fluid mixing between the layers while fluid flows within each layer or stream, which may make the separation much more efficient than in existing technologies, which do not have the one or more thin porous layers or sets of channels, tubes, or streams or streams to prevent or minimize mixing of adjacent streams.
During operation, the thin fluid layer separators may form a thin fluid layer or stream on the support surface with controlled thickness and minimized advection that is combined with forces such as one or more of magnetic, centrifugal, or electrostatic forces or concentration gradients to facilitate low cost, rapid, efficient separation of the entities in the thin fluid layers or streams. For example, the thin fluid layers, tubes, channels, or streams may have a thickness of a few micrometers to a few millimeters, such as about 2 mm to about 5 mm, about 1 mm to about 2 mm, about 750 μm to about 1.5 mm, about 600 μm to about 1 mm, about 500 μm to about 700 μm, about 400 μm to about 600 μm, about 300 μm to about 500 μm, about 200 μm to about 400 μm, about 150 μm to about 300 μm, about 100 μm to about 200 μm, about 75 μm to about 150 μm, about 50 μm to about 100 μm, about 25 μm to about 75 μm, about 10 μm to about 50 μm, about 5 μm to about 25 μm, or about 1 μm to about 10 μm. The control of the thickness of the thin layer across which the separation takes place makes the separation much more rapid than other technologies that use such forces. The layer or stream thickness is primarily controlled by flow rate, viscosity, porous liner thickness, porous liner properties, angle of incline, channel size, wire size, tube size, fiber size, length, and/or angular velocity. It is noted that any of the thin porous layers or channels, tubes, or fibers, individual and/or collectively, may exhibit any of the same thicknesses as the thin fluid layers or streams provided above.
In an embodiment, the thin fluid layers or streams separators disclosed herein may not require pressurized flow. Indeed, in an embodiment, no pressure for flow is applied. In an embodiment, the thin fluid layers or streams separators disclosed herein are scalable in design. In an embodiment, the thin fluid layers or streams separators disclosed herein may be used in systems that include cascades of the thin fluid layers, tubes, channels, or streams separators or a plurality of the thin fluid layers, tubes, channels, or streams separators in series to allow for multiple product streams at various stages of separation to optimize separation of specific products. In an embodiment, the thin fluid layer separators disclosed herein consume less than about 0.75 kilowatt hours per liter of fluid processed (kWhr/l), such as less than about 1×10−5 kWhr/l, less than about 2×10−5 kWhr/l, less than about 3×105 kWhr/l, less than about 5×10−5 kWhr/l, less than about 0.02 kWhr/l, less than about 0.05 kWhr/l, less than about 0.1 kWhr/l, less than about 0.2 kWhr/l, less than about 0.5 kWhr/l, or in ranges of about 1×10−5 kWhr/l to about 3×10−5 kWhr/l, about 2×10−5 kWhr/l to about 5×10−5 kWhr/l, about 4×10−5 kWhr/l to about 1×10−4 kWhr/l, about 1×10−4 kWhr/l to about 1×10−3 kWhr/l, 1×10−3 kWhr/l to about 0.01 kWhr/l, about 0.01 kWhr/l to about 0.02 kWhr/l, about 0.015 kWhr/l to about 0.04 kWhr/l, about 0.02 kWhr/l to about 0.06 kWhr/l, about 0.05 kWhr/l to about 0.1 kWhr/l, about 0.08 kWhr/l to about 0.15 kWhr/l, about 0.1 kWhr/l to about 0.2 kWhr/l, about 0.15 kWhr/l to about 0.3 kWhr/l, about 0.2 kWhr/l to about 0.4 kWhr/l, about 0.3 kWhr/l to about 0.5 kWhr/l, about 0.4 kWhr/l to about 0.6 kWhr/l, or about 0.5 kWhr/l to about 0.75 kWhr/l. In an embodiment, the electrical energy per liter of fluid that the thin fluid layers or streams separator requires to operate may depend on whether the thin fluid layers or streams separator includes a rotatable cylinder or an inclined surface. For example, a rotatable cylinder may require more electrical energy per liter (e.g., 0.01 kWhr/l to about 0.75 kWhr/l) than an inclined surface or crossing sets of channels (e.g., less than 0.1 kWhr/l). In an embodiment, the electrical energy per liter of fluid processed that the thin fluid layers or streams separator requires to operate may depend on the size of the thin fluid layers or streams separator since increasing the size of the thin fluid layers or streams separator (e.g., increase the number of liters per hour that the thin fluid layers or streams separator can receive) may decrease the electrical energy per liter needed to operate the separator.
In an embodiment, the thin fluid layers or streams separators disclosed herein may be configured to be used with any suitable fluid, such as water, ionic fluids, aqueous fluids, organic fluids, biological fluids, human body fluids, gases, molten salts, molten metals, molten slag, or molten glass. In an embodiment, the thin fluid layers or streams separators disclosed herein may be used to separate any suitable entities, such as, but not limited to at least one of lithium, sodium, potassium, magnesium, cerium, dysprosium, neodymium, lanthanum, magnesium, erbium, iron, copper, thallium, technetium, indium, xenon, iodine, yttrium, strontium, lutetium, rhenium, samarium, fluorine, gallium, zirconium, hydrogen, potassium, sulfur, chromium, selenium, carbon, plutonium, curium, americium, cerium, californium, lithium, helium, nickel, boron, vanadium, tungsten, tantalum, ruthenium, lead, germanium, gadolinium, zinc, or compounds, ions or isotopes thereof. In an embodiment, the thin fluid layers and streams separators disclosed herein may be configured to be used with fluids that have surfactants or other additives included therein.
Applications of the thin fluid layers or streams separators disclosed herein may include desalination, water purification, chemical concentration, separation of entities, separation of isotopes, medicinal separations, biological matter separations, and separation of different types of very fine particles based on differences in densities, mobilities, solvent interactions, charge, electrochemical potential, and magnetic susceptibilities.
In an embodiment, the thin fluid layers and streams separators disclosed herein may include a centrifugal device. (e.g., applies at least a centrifugal force to the thin fluid layers and streams)
The centrifugal force F exerted on the entity 106 in a centrifugal device is shown in equation (1),
F=mrω
2 (1)
where m is the mass of the entity 106, r is the radius from the center of the rotatable cylinder 102 at the point of force measurement, and ω is the angular velocity. The centrifugal force may lead to acceleration of the entity 106 in the thin fluid layers or streams 104 and a resultant velocity towards the rotatable cylinder 102. The entity 102 may also have a relatively high velocity that is tangential to the rotatable cylinder 102 as well as a downward velocity due to gravity if the rotatable cylinder 102 is vertical. The present embodiment differ from gas centrifuge separations, in that no expensive high speed centrifuge is required. Where a centrifugal force is applied, the employed rotational speed may be far slower than typical in high speed gas centrifuge separations (e.g., less than 10,000 RPM, less than 5,000 RPM, or less than 3,000 RPM.
The centrifugal field allows more dense and mobile entities to be separated from less dense and less mobile entities. For example,
In embodiments where the only applied force for separation is the centrifugal force, the time for separation may depend on the centrifugal force, which, as previously discussed, may be related to the rotational velocity squared and the diameter of the cylinder as well as by the flow rate of thin fluid layers or streams 104 which influences the thickness of the thin fluid layers or streams 104 and the thin fluid layers or streams 104 downward velocity (assuming the rotating cylinder is oriented with the axis of rotation oriented vertically). The time for separation also may depend on any other forces that are applied (e.g., magnetic, electric, etc.) as well. The viscosity of the thin fluid layers or streams 104, which may be strongly influenced by temperature, may also affect the time for separation. The time for separation may also be influenced by the location of the collection port (e.g., 108) relative to the input of fluid.
In an embodiment, the thin fluid layers or streams separator 100 may rotate at a speed of greater than 0 RPM to about 5000 RPM, such as in ranges of greater than 0 RPM to about 1800 RPM, about 500 RPM to about 1500 RPM, about 1000 to about 2000 RPM, or about 1500 RPM to about 3000 RPM. Those of skill in the art will appreciate that such speeds are significantly slower than typically required in high speed centrifuges, for gas centrifuge separations. The slower speeds and simpler structure results in a system that is far less expensive to provide and operate.
The thin fluid layers or streams separator 200 may also include one or more thin porous layers and streams 212 (e.g., thin porous liners, coatings, and/or surfaces) disposed on the inner surface 203 of the rotatable cylinder 202 to create, maintain, and/or stabilize one or more thin fluid layers or streams, in the thin porous layer 212, flowing therein. In an example, the thin porous layers and streams 212 may be made using fibrous material (e.g., large thin sheets of lint free KIM wipes, thin porous fibers or networks of fibers, thin porous ceramics, thin porous metals or other suitable porous materials that can withstand the expected environment) that line the inner wall surface 203 of the rotatable cylinder 202. The thin porous layers and streams 212 may be inserted into the thin fluid layers or streams separator 200 to mitigate potential turbulence in the thin fluid layers or streams. For instance, not wishing to be bound by theory, it is currently believed that, as the speed of the rotation increases, there may be more potential for fluid flow in the thin fluid layers or streams to become somewhat turbulent. The turbulence may cause mixing which, in turn, may make the separation of the entities in the thin fluid layers or streams more difficult and less efficient. Because the thin porous layers 212 holds the thin fluid layers or streams by capillary forces, the thin fluid layers or streams are not as free to flow and form turbulent regions or wavefronts. Thus, the thin porous layers 212 may hold the thin fluid layers or streams to the wall of the rotatable cylinder 202 and may allow the centrifugal forces to perform the separation through the thin porous layers 212 towards the wall of the rotatable cylinder 202 as the thin fluid flows down through the rotatable cylinder 202. Also, the thin porous layers 212 may inhibit turbulent mixing. It is noted that the thin porous layers 212 are optional and may be omitted from the thin fluid layers or streams separator 200, although when included, they provide advantages noted above.
In an embodiment, the thin porous layers and streams 212 can be selected to create a chromatography-like separation effect. The use of the thin porous layers and streams 212 may provide an additional opportunity for separation by using porous media with varying properties. For example, thin porous layers and streams and streams 212 that have properties that are similar to those of a chromatography column may enhance the separation of entities that are attracted to the thin porous layers and streams 212. In such an example, thin porous layers and streams or sets of channels, tubes, or streams 212 may facilitate separation of entities based on the combination of attraction to the thin porous layers and streams 212 and the properties of the entities undergoing separation. For instance,
The at least one force application device of the thin fluid layers and streams separator 300 includes one or more magnets 314 that are configured to apply a magnetic field to the thin fluid layers and streams 304. Applying the magnetic field to the thin fluid layers and streams 304 may enhance separation of entities in the thin fluid layers and streams 304. The applied magnetic field may improve and speed up the separation as well as decrease energy needed to separate the entities, and may facilitate or augment separation of entities based on magnetic susceptibility and mobility.
In an example, not wishing to be bound by theory, the entities in the thin fluid layers and streams may act as charged particles (e.g., ions). A charged particle moving perpendicular to a magnetic field experiences a force that causes the circular motion of the particle with radius of trajectory ‘r’ as shown in equation 2:
where ‘m’ is the mass, ‘q’ is the charge, and is the velocity of particle. ‘B’ is the applied magnetic field.
Thus, in the case of constant charge, velocity, and applied magnetic field, the radius of the path of the charged entities in the thin fluid layers and streams separator will depend on the mass of the entity. In other words, entities with higher mass will experience more deflection than lighter entities. In other words, while applying the magnetic field, the flow of the entities in the thin fluid layers and streams separators may depend on mass and charge. In such cases, more dense entities in the thin fluid layers and streams can be separated from the lighter entities.
The magnet 314 may include any suitable magnet. In an embodiment, the magnet 314 includes one or more permanent magnets, such as permanent rare earth magnets. In an embodiment, the magnet 314 includes one or more electromagnetics. In an embodiment, the magnet 314 may run substantially all of or only a portion of the length of the rotatable cylinder 302. In an embodiment, the magnets 314 are configured to be adjustable and/or tunable thereby allowing the magnetic field to be selected to optimize separations.
In an embodiment, the magnet 314 includes a plurality of magnets, such as an outer magnet 314a and an inner magnet 314b, e.g., with opposing polarities. In an embodiment, there is a gap 316a between the outer magnet 314a and the rotatable cylinder 302 such that the inner magnet 314a does not inhibit rotation of the rotatable cylinder 302. In an embodiment, there is a gap 316b between the inner magnet 314b and the thin fluid layers and streams 304 such that the inner magnet 314b does not inhibit the flow of the thin fluid layers and streams 304.
The at least one force application device of the thin fluid layers and streams separator 400 includes one or more electrodes 418 that are configured to apply an electric and/or electrostatic field to the thin fluid layers and streams 404. The one or more electrodes 418 may include an outer electrode 418a and an inner electrode 418b having opposing polarities. Applying the electric and/or electrostatic field to the thin fluid layers and streams 404 may enhance separation of the thin fluid layers and streams 404. For example, while applying the electric and/or electrostatic field, the flow of entities in the thin fluid layers and streams separator may depend on the charge of the entities (e.g., the effect of the charge of the entities on separation of the entities may be more pronounced with the electric and/or electrostatic field than with a magnetic field). The applied electric and/or electrostatic field may improve and speed up the separation as well as decrease energy (e.g., rotational energy) need to separate the entities, and facilitate or augment separation of entities based on charge and mobility. For example, the use of permanent or oscillating electrodes in the center (e.g., the inner electrode 418a) and around the perimeter (e.g., outer electrode 418b) with opposite polarities can augment the centrifugal force to improve the separation of charged entities. These forces can be oscillated to resonant frequencies of desired target entities in the fluid to be concentrated (or depleted).
In an embodiment, there is a gap 416a between the outer electrode 418a and the rotatable cylinder 402 such that the outer electrode 418a does not inhibit rotation of the rotatable cylinder 402. In an embodiment, there is a gap 416b between the inner electrode 418b and the thin fluid layers and streams 404 such that the inner electrode 418b does not inhibit the flow of the thin fluid layers and streams 404.
It is noted that any of the thin fluid layers and streams separators disclosed herein may include one or more additional force application devices that are configured to apply forces to the thin fluid layers and streams, where such forces may be other than or in addition to centrifugal forces, magnetic forces, and/or electrostatic forces. For example, any of the thin fluid layers and streams separators disclosed herein may include a force application device that uses electrolytic forces to separate entities in a thin fluid layer and stream. In such an example, the force application device may include one or more electrodes in contact with the thin fluid layers and streams and the potential between the electrodes may be configured to reduce or electrodeposit desired, more dense, more charged, and/or more magnetically susceptible entities. The electrodes that are in contact with the thin fluid layers and streams may include interior ring electrodes on the interior wall of the rotatable cylinder. The interior ring electrodes may exhibit electrochemical potential that can be adjusted to harvest entities in a desired sequence.
The rotatable cylinder 602 includes a tapering section 622 near a bottom 624 thereof. The tapered section 622 causes the centrifugal force applied to the thin fluid layers and streams in this region to decrease which, in turn, causes the thin fluid layers and streams to increase a thickness thereof. The thin fluid layers and streams separator 600 may also include a physical baffle or other separator 626 adjacent to the tapered section 622. As shown, separator 626 may have a spiral configuration. Since the fluid layers and streams is thicker at and/or below the tapered section 622, the physical separator 626 may physically separate an outer portion of the fluid layers and streams from an inner portion of the fluid layers and streams. Separating the outer and inner portion of the fluid layers and streams may more effectively facilitate physical separation of the entities therein, since the outer portion of the fluid layers and streams may have a higher concentration of more dense entities than the inner portion. The thin fluid layers and streams separator 600 may include a first collection device 620a that is configured to collect fluid from the inner portion of the fluid layers and streams and a second collection device 620b that is configured to collect fluid from the outer portion of the fluid layers and streams.
The thin fluid separators disclosed herein may include at least one support that includes an inclined surface, e.g., instead of a rotatable cylinder (e.g., centrifugal device).
The thin fluid layer separator 700 is shown as including at least one force application device configured to apply additional forces (in addition to gravity) to the thin fluid layers and streams similar to the other thin fluid layers and streams separators disclosed herein. In an example, the force application device may include electrodes that are configured to apply an electric and/or electrostatic field to the thin fluid layers and streams. The electrodes may include a top electrode 718 and an opposing bottom electrode that can be integrally formed with the inclined plate 730 (as illustrated) or provided distinct from the inclined plate 730. In an example, the force application device of the thin fluid layers and streams separator 700 may include magnets in place of or in addition to the illustrated electrodes that apply a magnetic force to the thin fluid layers and streams. In an example, the thin fluid layers and streams separator 700 may also include one or more thin porous layers or sets of channels, tubes, or streams 712 disposed on a surface of the inclined surface 730 to inhibit turbulence in the thin fluid layer. The one or more thin porous layers or sets of channels, tubes, or streams 712 may include a single thin porous layer or sets of channels, tubes, or streams 712 or a plurality of thin porous layers or sets of channels, tubes, or streams 712 that may each affect how the entities flow therein.
By way of example, the incline of the surface (e.g., surface 703) may range from 5° to 85°, from 10° to 70°, from 20° to 60°, or from 30° to 50°, relative to a 90° incline being vertical.
In an embodiment, the thin fluid layers and streams separator 700 may operate in a way that is similar to a mass spectrometer with the additional benefit of enhancing ionic separations based on charge and mobility of ions in solution. In mass spectrometers, atoms are ionized to allow them to be accelerated by a voltage gradient to move them through a magnetic field, whereas the entities flowing through the thin fluid layers and streams separator 700 may be moving with the flowing fluid through the magnetic field as well as an electric and/or electrostatic field. In mass spectrometers the ions in a vacuum are displaced by approximately 1 cm in the device. In the thin fluid layers and streams separator 700, the desired path length is related to the thickness of the thin fluid layers and streams, which is on the order of 100 μm (far smaller than displacement in a mass spectrometer).
As previously discussed, entities (e.g., elements, molecules, ions, isotopes, and particles with different properties) can be separated based on differences in properties such as density, charge, conductivity, electrochemical potential, size, mass, etc. In some embodiments, the fluid separators disclosed here may use transverse diffusion across a laminar stream due to concentration gradients and the use of thin layers and streams instead of or in addition to separating based on differences in properties such as density, charge, conductivity, electrochemical potential, size, mass, etc.
The thin fluid layers and streams separator 800 may be formed using any suitable technique. In an embodiment, the microfluidic separation channel 810 may be created by joining a patterned polydimethylsiloxane (PDMS) and a transparent slide glass after appropriate treatment such as oxygen plasma. First, a thin layer of SU-8 or other photoresist may be spin-coated on a smooth silicon wafer, and photolithography will be conducted to pattern the microfluidic separation channel. Then, the PDMS may be poured onto the patterned SU-8 mold and cured at designated temperature for 2 hours. The PDMS may be relieved from the SU-8 mold to create the pattern of the microfluidic separation channel on the PDMS. Finally, the patterned PDMS layer may be bonded with the glass substrate after treating the surface with oxygen plasma for a few minutes (e.g., 1-5 minutes).
The thickness of the layer can be controlled by a combination of a porous support media and flow velocity. The thin, porous structure is generally needed to control layer thickness, stabilize laminar flow, and prevent solution mixing that would otherwise remix the entities separated by the application of the separation force. The thin fluid layers and streams separator 800 may be or include what is generally known as an H-filter or H-sensor due to its geometrical structure. A buffer fluid with two entities (e.g., isotope with lower mass and isotope with higher mass) are circulated through one inlet 802 of the H-filter. A pure buffer fluid is injected at the other inlet 804. The two fluids are forced into a junction (e.g., T or Y-junction). The width of the channels may shrink beyond the intersection 806. The two fluids move side by side along the primary channel 810. Due to the laminar nature of flow in microfluidic channels 810, turbulent mixing is not present and the only mixing is through diffusion. One of the two entities, being lighter, has a larger diffusion constant than the other entity and will start to diffuse into the pure buffer fluid more rapidly than the heavier entity. Design of the H-filter should be such that the length of the primary channel is long enough to allow sufficient time for the lighter entity to diffuse significantly more than the heavier entity. In this process of separation, the control-related assumptions are important. The Reynold's number should be small (i.e., laminar flow), the channels should be wide and rigid, and the fluids should have substantially constant and similar viscosity.
The Zimm model describes the polymer dynamics in a dilute solution. The diffusivity (D) and the relaxation time (τ) in the solvent are given as
where kB is Boltzmann's constant, T is the temperature, η is the viscosity of the solvent, M is the molecular weight of the solute, and the exponent v is given by 0.588 in the exemplary solvent.
In the solution, the entity with high mass diffuses more slowly than the entity with the low mass due to its larger weight. Additionally, the mass of the entity is also related to the hydrodynamic radius. The permeation data for hydrogen isotopes were reported for tetrafluoroethylene and polyethylene and found that the value for hydrogen and D2 were quite different (D for Hydrogen ˜1.47×10−7 cm2/s whereas for D2 the diffusion constant was ˜1.16×10−7 cm2/s). Similarly, for Li isotopes the value of the diffusion constant is different for two isotopes and the difference in diffusivity increases in certain environments and in the presence of specific solvents. This change in diffusivity can be seen in the context of the electrochemical isotope effect theory that has been derived thoroughly by Kavner et al. with reference to the Marcus charge transfer theory. There will be a difference in the relaxation time between the isotopes of different mass that can provide a sufficiently dynamic contrast to facilitate separation of the isotopes from the mixture using transverse diffusion.
There are several factors that may affect separation of the mixture containing the entities. In an example, separation of the mixture may depend on the flow rates of solution since the flow rate affects layers and streams thickness, residence time, and stream split ratio. The separation of the mixture may also depend on layers and streams thickness which may be determined based on flow rate and residence time. Other factors include flow speed residence time, and stream split ratio. The thin fluid layers and streams separator 800 may also include a very thin fiber liner to provide a stabilizing influence on fluid flow in the pipe and which holds the fluid by capillary forces. The size, type, and thickness of the fiber may also affect the separation of the mixture.
Diffusion is also influenced by temperature. At the point when surrounding temperature increases, the solvent substances diffuse more rapidly in a fluid. Based on this principle, the transverse migration of the entities in appropriate solvent occurs rapidly through the interface boundary of the laminar flow in the microfluidic channel.
During use of the thin fluid layers and streams separator 1000, more massive entities will move toward the wall of the cylinder channel 1010 more completely than lighter entities due to the diffusion across the interface of two overlaid laminar layers and streams of solution and the boundary constraint at the cylinder channel 1010. Therefore, the denser entities are concentrated near the bottom of the tube wall and lighter entities can be collected in fluid exiting through outlets 1008 in the channel 1010 at a higher concentration than in the input bulk solution. Therefore, it is possible to separate more dense entities in a thin layers and streams separator in a short period of time. It is also possible to sequentially remove entities at different locations along the length of the tube channel as illustrated in
The thin fluid layers and streams separators disclosed herein may exhibit a structure other than the structures illustrated in
As previously discussed above, the thin fluid layers and streams separators disclosed herein may include a porous material. In an example, the porous material may include two-dimensional materials, such as one or more of graphene, MoS2, MXene, metal-organic frameworks (MOFs), and covalent organic framework nanosheets. In an example, the porous material may include nanoporous materials. Nanoporous materials may have the potential to separate hydrogen isotopes by a process known as kinetic quantum sieving. Examples of nanomaterials include CNT, rGO, and MOFs. In an example, the porous material may include functionalized multiwalled carbon nanotube-ZnO composite that have shown specific selectivity towards specific ions.
As previously discussed above, the thin fluid layers and streams separators may include and/or receive a solvent. Solvents may play an important role in the separation of ions. In the case of the thin layers and streams laminar flow separator, an example of a solvent may include a low-density solvent such as isopropanol, included in a small amount. An example of a high-density solvent includes pyridinium/aluminum chloride based ionic fluid which may influence the separation of higher density isotopes such as those of calcium, copper and cobalt.
Any of the thin fluid layers and streams devices disclosed herein may include one or more additional components other than what is illustrated in the drawings. For example, any of the thin fluid layers and streams devices disclosed herein may include at least one of a pump, coupler, pipe, or mounting equipment.
A solution containing 1522 ppm of lithium, 1000 ppm of sodium, 1000 ppm of potassium, 1000 ppm of magnesium, and 0.1% Tween 20 (nonionic surfactant) that was diluted by a factor of 10 was pumped into the spinning tube of the thin fluid layers and streams separator of working example 1 using a peristaltic pump (i.e., the fluid source) at a flowrate of approximately 50 ml per minute. Solution collected from the lower bucket from the small holes in the pipe spinning at 1250 RPM was diluted by a factor of 100 and sent for ICP analysis at an independent lab. The results were 1.40, 1.38, 1.48, and 1.92 ppm for magnesium, potassium, sodium, and lithium, respectively. The ratio of the heavier elements (magnesium, potassium, and sodium) relative to that of the much lighter reference element (lithium) increased by an average of about 12%, which suggested that the thin fluid layers and streams separator of working example 1 was able to separate entities based on mass.
The same stock solution used in working example 1 was used in working example 2 (e.g., a solution including 1522 ppm of lithium, 1000 ppm of sodium, 1000 ppm of potassium, 1000 ppm of magnesium, and 0.1% Tween 20), with the solution being diluted by a factor of 10 for working example 2. The solution flow rate was 30-40 ml/minute. The residence time was approximately 15 seconds. During the test, samples were collected from the lower bucket. After the test, the collected samples were diluted by a factor of approximately 10 before being analyzed by inductively coupled plasma spectroscopy. The results from tests at the different flow rates are shown in comparison to the baseline solution in
The thin fluid layers and streams separator of working example 3 was tested by flowing a solution down the rotatable cylinder that contained approximately 75 ppm cerium, 75 ppm dysprosium, 81 ppm neodymium, 78 ppm lanthanum, 95 ppm magnesium, 120 ppm lithium, and 84 ppm erbium. The rotatable cylinder was rotated at 655 RPM and 1300 RPM.
Although the increases in concentrations of the entities in working examples 1-3 were encouraging, it is believed that as the speed of the rotation increases, there may be more potential for the fluid to become somewhat turbulent. It is currently believed that the turbulence may cause mixing of the thin fluid layers and streams thereby making the separation more difficult and less efficient. Thus, a thin fluid layers and streams separator that was similar to the thin fluid layers and streams separator schematically shown in
The thin fluid layer separator of working example 4 was tested using 2 solutions. The first solution included lithium ions and was flowed down the rotatable cylinder at 1300 RPM and 60 ml/minute flow rate. The collected fluid from the first solution was analyzed by ICP MS and the analysis showed that the lithium ion concentration decreased by 23% in the fluid extracted from the side ports. A second solution included cerium, dysprosium, neodymium, magnesium, iron, and copper ions and was flowed down the rotatable cylinder at 1800 RPM and 60 ml/minute flow rate.
An additional test was performed on the thin fluid layers and streams separator of working example 5 for 3.5% and 7.0% NaCl solutions. The solutions were allowed to pass through the device and were collected at the bottom of the plate. The solutions from the top and bottom layers were examined using electrochemical impedance spectroscopy (EIS) to determine solution conductivity. A three-electrode method was used for EIS tests. The Nyquist plots were obtained and for model fitting using a simple method, the solution resistance for one layer solution was two times higher than that of the second one.
The thin fluid layers and streams separator illustrated in
The results are presented below in Table 1 to show the effects of flow rate and magnet orientation on the separation of H+ ions (pH measurement based), Cu2+ ions (selective ion electrode measurement based), and Fe3+/Fe2+ ion ratio (Eh measurement based). Table 1 demonstrates that the separator illustrated in
As shown in
While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting.
Various aspects of the present disclosure, including devices, systems, and methods may be illustrated with reference to one or more embodiments or implementations, which are exemplary in nature. As used herein, the term “exemplary” means “serving as an example, instance, or illustration,” and should not necessarily be construed as preferred or advantageous over other embodiments disclosed herein. In addition, reference to an “implementation” of the present disclosure or invention includes a specific reference to one or more embodiments thereof, and vice versa, and is intended to provide illustrative examples without limiting the scope of the invention, which is indicated by the appended claims rather than by the following description.
As used throughout this application the words “can” and “may” are used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Additionally, the terms “including,” “having,” “involving,” “containing,” “characterized by,” as well as variants thereof (e.g., “includes,” “has,” “involves,” “contains,” etc.), and similar terms as used herein, including within the claims, shall be inclusive and/or open-ended, shall have the same meaning as the word “comprising” and variants thereof (e.g., “comprise” and “comprises”), and do not exclude additional un-recited elements or method steps, illustratively. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure pertains.
In addition, unless otherwise indicated, numbers expressing quantities, constituents, distances, or other measurements used in the specification and claims are to be understood as optionally being modified by the term “about” or its synonyms. When the terms “about,” “approximately,” “substantially,” or the like are used in conjunction with a stated amount, value, or condition, it may be taken to mean an amount, value or condition that deviates by less than 20%, less than 10%, less than 5%, less than 1%, less than 0.1%, or less than 0.01% of the stated amount, value, or condition.
As used herein, the term “between” includes any referenced endpoints. For example, “between 2 and 10” includes both 2 and 10.
Some ranges may be disclosed herein. Additional ranges may be defined between any values disclosed herein as being exemplary of a particular parameter. All such ranges are contemplated and within the scope of the present disclosure.
Disclosure of certain features relative to a specific embodiment of the present disclosure should not be construed as limiting application or inclusion of said features to the specific embodiment. Rather, it will be appreciated that other embodiments can also include said features, members, elements, parts, and/or portions without necessarily departing from the scope of the present disclosure. Moreover, unless a feature is described as requiring another feature in combination therewith, any feature herein may be combined with any other feature of a same or different embodiment disclosed herein. Furthermore, various well-known aspects of illustrative systems, methods, apparatus, and the like are not described herein in particular detail in order to avoid obscuring aspects of the example embodiments. Such aspects are, however, also contemplated herein.
Accordingly, the present disclosure may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. While certain embodiments and details have been included herein and in the attached disclosure for purposes of illustrating embodiments of the present disclosure, it will be apparent to those skilled in the art that various changes in the methods, products, devices, and apparatus disclosed herein may be made without departing from the scope of the disclosure or of the invention, which is defined in the appended claims. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
This application claims priority to and the benefit of U.S. Provisional Patent Application Ser. No. 63/396,670 entitled THIN LIQUID FILM SEPARATORS AND METHODS OF USING THE SAME, filed Aug. 10, 2022 which is herein incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63396670 | Aug 2022 | US |
