Isopropyl alcohol separation from liquid streams

Abstract

Methods and related systems for separating isopropyl alcohol (IPA) from aqueous liquid streams are generally described. Some aspects are directed to treatment of aqueous streams (e.g., semiconductor processing wastewater streams) containing isopropyl alcohol to remove some or all of the IPA, thereby generating a stream rich in IPA and, in some instances, a stream diminished in IPA. The IPA may be removed via a combination of membrane-based separation (e.g., reverse osmosis) and distillation. Certain aspects relate to distillation apparatus configurations that can efficiently and effectively separate the IPA from an aqueous stream that is enriched in the IPA (e.g., via prior membrane-based concentration). For example, the distillation apparatus may be configured to achieve a relatively low residence time of IPA vapor within its distillation vessel. The low residence time may be achieved, for example, using a distillation vessel with a relatively low height and / or a short-bed configuration.

Description

[0001] ISOPROPYL ALCOHOL SEPARATION FROM LIQUID STREAMS

[0002] TECHNICAL FIELD

[0003] Methods and related systems for separating isopropyl alcohol from aqueous liquid streams are generally described.

[0004] SUMMARY

[0005] Methods and related systems for separating isopropyl alcohol from aqueous liquid streams are generally described. The subject matter of the present invention involves, in some cases, interrelated products, alternative solutions to a particular problem, and / or a plurality of different uses of one or more systems and / or articles.

[0006] Certain aspects relate to methods for separating isopropyl alcohol (IPA) from an aqueous IPA-recovery input stream. In some embodiments, the method comprises transporting a membrane separator retentate input comprising at least a portion of the aqueous IPA-recovery input stream comprising IPA to a retentate side of a membrane separator such that: a membrane separator retentate output exits the retentate side of the membrane separator, the membrane separator retentate output having a concentration of IPA that is greater than a concentration of IPA in the membrane separator retentate input, and at least a portion of water from the membrane separator retentate input is transported from the retentate side of the membrane separator, through a semi-permeable membrane of the membrane separator, to a permeate side of the membrane separator; transporting a distillation input comprising at least a portion of the membrane separator retentate output to a distillation apparatus; forming a vapor comprising at least a portion of the IPA from the distillation input in a distillation vessel of the distillation apparatus; and condensing at least a portion of the vapor to form at least a portion of an IPA-rich liquid output stream comprising IPA at a concentration greater than a concentration of IPA in the distillation input; wherein: (a) the distillation vessel has a height that is less than or equal to 5 m, and / or (b) the vapor has a residence time in the distillation vessel of less than or equal to 20 minutes.

[0007] In certain embodiments, the method comprises transporting a membrane separator retentate input comprising at least a portion of the aqueous IPA-recovery input stream comprising IPA to a retentate side of a membrane separator such that: a membrane separator retentate output exits the retentate side of the membrane separator,

[0008] 13191435.1 the membrane separator retentate output having a concentration of IPA that is greater than a concentration of IPA in the membrane separator retentate input, and at least a portion of water from the membrane separator retentate input is transported from the retentate side of the membrane separator, through a semi-permeable membrane of the membrane separator, to a permeate side of the membrane separator; transporting a distillation input comprising at least a portion of the membrane separator retentate output to a distillation apparatus; forming a vapor comprising at least a portion of the IPA from the distillation input in a distillation vessel of the distillation apparatus, wherein the distillation apparatus induces separation of at least some of the vapor from at least some water from the distillation input via centrifugal force; and condensing at least a portion of the vapor to form at least a portion of an IPA -rich liquid output stream comprising IPA at a concentration greater than a concentration of IPA in the distillation input.

[0009] Some aspects relate to systems for separating isopropyl alcohol (IPA) from an aqueous IPA-recovery input stream. In some embodiments, the system comprises a membrane separator comprising at least one semi-permeable membrane defining a retentate side of the membrane separator and a permeate side of the membrane separator, wherein the retentate side of the membrane separator is configured to: receive a membrane separator retentate input comprising at least a portion of the aqueous IPA- recovery input stream comprising IPA, and output a membrane separator retentate output having a higher concentration of IPA than the membrane separator retentate input; and a distillation apparatus comprising: a distillation entry fluidically connected to the retentate side of the membrane separator and configured to receive a distillation input; a distillation liquid outlet configured to output an IPA-rich liquid output stream; and a distillation vessel fluidically connected to the distillation entry and the distillation liquid outlet, wherein the distillation vessel has a height along that is less than or equal to 5 m.

[0010] In certain embodiments, the system comprises a membrane separator comprising at least one semi-permeable membrane defining a retentate side of the membrane separator and a permeate side of the membrane separator, wherein the retentate side of the membrane separator is configured to: receive a membrane separator retentate input comprising at least a portion of the aqueous IPA-recovery input stream comprising IPA, and output a membrane separator retentate output having a higher concentration of IPA than the membrane separator retentate input; and a distillation apparatus comprising: a distillation entry fluidically connected to the retentate side of the membrane separator

[0011] 13191435.1 and configured to receive a distillation input; a distillation liquid outlet configured to output an IPA-rich liquid output stream; and a distillation vessel fluidically connected to the distillation entry and the distillation liquid outlet, wherein the distillation apparatus is configured to induce separation of at least some of vapor from at least some water from the distillation input via centrifugal force.

[0012] Other advantages and novel features of the present invention will become apparent from the following detailed description of various non-limiting embodiments of the invention when considered in conjunction with the accompanying figures. In cases where the present specification and a document incorporated by reference include conflicting and / or inconsistent disclosure, the present specification shall control.

[0013] BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying figures, which are schematic and are not intended to be drawn to scale. In the figures, each identical or nearly identical component illustrated is typically represented by a single numeral. For purposes of clarity, not every component is labeled in every figure, nor is every component of each embodiment of the invention shown where illustration is not necessary to allow those of ordinary skill in the art to understand the invention. In the figures:

[0015] FIG. 1 is a schematic diagram of an example of a system configured to separate IPA from a liquid stream, according to some embodiments;

[0016] FIG. 2A is a schematic diagram of an example of a distillation apparatus within a system configured to separate IPA from a liquid stream, according to some embodiments;

[0017] FIG. 2B is a schematic diagram of an example of a distillation apparatus within a system configured to separate IPA from a liquid stream using an azeotrope breaking agent, according to some embodiments;

[0018] FIG. 2C is a schematic diagram of an example of a distillation apparatus within a system configured to separate IPA from a liquid stream, the distillation apparatus comprising a boiler and a reflux drum, according to some embodiments;

[0019] FIG. 2D is a schematic cross-sectional diagram of an example of a distillation vessel comprising a rotating disc, according to some embodiments;

[0020] 13191435.1 FIG. 3A is a schematic illustration of an example of a single-membrane membrane separator, according to some embodiments;

[0021] FIG. 3B is a schematic illustration of an example of a membrane separator comprising multiple semi-permeable membranes fluidically connected in parallel, according to some embodiments;

[0022] FIG. 3C is a schematic illustration of an example of a membrane separator comprising multiple semi-permeable membranes fluidically connected in series, according to some embodiments; and

[0023] FIG. 4 is a data plot showing total organic carbon (TOC) for a membrane separator retentate output and a membrane separator permeate output versus concentration factor, according to some embodiments.

[0024] DETAILED DESCRIPTION

[0025] Methods and related systems for separating isopropyl alcohol (IPA) from aqueous liquid streams are generally described. Some aspects are directed to treatment of aqueous streams (e.g., semiconductor processing wastewater streams) containing isopropyl alcohol and one or more other liquid components to remove some or all of the IPA, thereby generating a stream rich in IPA and, in some instances, a stream diminished in IPA. The IPA may be removed via a combination of membrane -based separation (e.g., reverse osmosis) and distillation. Certain aspects relate to distillation apparatus configurations that can efficiently and effectively separate the IPA from an aqueous stream that is enriched in the IPA (e.g., via prior membrane-based concentration). For example, the distillation apparatus may be configured to achieve a relatively low residence time of IPA vapor within its distillation vessel. The low residence time may be achieved, for example, using a distillation vessel with a relatively low height and / or a short-bed configuration.

[0026] Certain processes, such as semiconductor processing, produce liquid streams that must be treated for environmental, safety, and / or economic reasons. For example, semiconductor processing facilities may produce wastewater streams containing chemical species such as IPA whose removal (and / or recovery) would be beneficial. One strategy for separating IPA from waste streams is by distillation. However, complete (or near-complete) separation of IPA from water by distillation presents challenges. One challenge is that IPA may be relatively dilute in the waste stream (e.g.,

[0027] 13191435.1 less than 20,000 mg / L), and so a high energy input and / or large equipment footprint may be required to effectively recover the desired amount of the IPA. Further, IPA and water form a boiling point azeotrope resulting in the distillate containing a mixture of IPA and a significant amount of water. These challenges can contribute to technical and capital expenditure inefficiencies in wastewater treatment systems. However, it has been realized in the context of this disclosure that a combination of pre-enrichment of the IPA (e.g., via a membrane separator configured to reject a relatively high percentage of IPA) and distillation apparatuses with certain configurations (e.g., to achieve low residence time for IPA) can at least partially address these challenges. Accordingly, the methods and systems of this disclosure provide an approach to treating IPA-containing aqueous liquid streams using, in some instances, a membrane separator (e.g., reverse osmosis separator) and a distillation apparatus (e.g., a short-bed distillation apparatus). Some embodiments may further include use of an azeotrope-breaking agent (e.g., sodium chloride) to promote effective separation of IPA and water during distillation.

[0028] Methods for treating streams containing IPA, and related systems, are generally described. FIG. 1 shows a schematic illustration of system 100, which is an example of a system in which certain methods described herein may be carried out.

[0029] Some embodiments comprise separating IPA from an aqueous IPA-recovery input stream. Referring again to FIG. 1, aqueous IPA-recovery input stream 101 may be fed into system 100 for treatment.

[0030] The aqueous IPA-recovery input stream is an aqueous stream. In some embodiments, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, at least

[0031] 97 wt%, and / or up to 98 wt%, up to 99 wt%, up to 99.8 wt%, or more of the liquid of the aqueous IPA-recovery input stream is water. The aqueous IPA-recovery input stream may be a mixture of water and IPA (and other species in some instances). In some embodiments, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, at least

[0032] 98 wt%, at least 99 wt%, at least 99.8 wt%, at least 99.9 wt%, or more (e.g., all) of the liquid of the aqueous IPA-recovery input stream is a combination of water and IPA. The aqueous IPA-recovery input stream may comprise IPA in a relatively large amount. In some embodiments, the aqueous IPA-recovery input stream comprises IPA in an amount of greater than or equal to 2,000 mg / L, greater than or equal to 3,000 mg / L, greater than or equal to 5,000 mg / L, greater than or equal to 10,000 mg / L, and / or up to 20,000 mg / L or greater. Combinations of these ranges are possible.

[0033] 13191435.1 In some embodiments, the aqueous IPA -recovery input stream has a relatively high pH. In some embodiments, the aqueous IPA-recovery input stream has a pH of greater than or equal to 4, greater than or equal to 5, greater than or equal to 6, greater than or equal to 7, greater than or equal to 8, greater than or equal to 9, greater than or equal to 10, greater than or equal to 11, and / or up to 12, up to 13, up to 14, or greater. Combinations of these ranges are possible.

[0034] The aqueous IPA-recovery input stream may contain or be derived from any of a variety of sources, e.g., that produce streams containing both water and IPA. As mentioned above, in some embodiments, the aqueous IPA-recovery input stream is or is derived from a wastewater stream. The wastewater stream may be an effluent from an industrial process (e.g., a manufacturing process and / or chemical or materials synthesis process). In some embodiments, the wastewater stream is a semiconductor processing wastewater stream. Accordingly, some embodiments relate to receiving a semiconductor processing waste water stream and transporting at least a portion of the semiconductor processing wastewater stream to the water treatment system, forming some or all of the aqueous IPA-recovery input stream. Semiconductor processing facilities include those used to fabricate semiconductor devices. An example of a semiconductor device is a microelectronics device, including, but not limited to, processors such as computer processing units (CPUs), graphical processing units (GPUs), and / or integrated circuits. Semiconductor processing wastewater may contain at least some components (e.g., residual reagents, reaction products, and / or spectator species) that contacted a semiconductor during a semiconductor processing process (e.g., a process for the formation of electronics from silicon semiconductors, III-V semiconductors, and / or other types of semiconductors).

[0035] In some such embodiments, the aqueous IPA-recovery input stream undergoes one or more pretreatment processes. For example, the aqueous IPA-recovery input stream may be subjected to filtration (e.g., from an automatic backwashing filter and / or a cartridge filter).

[0036] In some embodiments, the aqueous IPA-recovery input stream is treated to separate at least a portion of the IPA in the aqueous IPA-recovery input stream from at least a portion of the water in the aqueous IPA-recovery input stream. For example, in some embodiments, water is removed from the aqueous IPA-recovery input stream, thereby forming a stream having a greater concentration of IPA than in the aqueous IPA-

[0037] 13191435.1 recovery input stream. In some such embodiments, a liquid stream that comprises water and that is free of IPA or comprises IPA at a lower concentration than in the aqueous IPA-recovery input stream is also formed. For example, the membrane separator permeate output discussed below may comprise at least one stream that comprises water and that is free of IPA or comprises IPA at a lower concentration than in the aqueous IPA-recovery input stream (e.g., as purified water).

[0038] Some embodiments comprise transporting a membrane separator retentate input (e.g., a membrane separator retentate inlet stream) to a retentate side of a membrane separator. A membrane separator refers to a collection of components including one or more semi-permeable membranes configured to perform a membrane-based separation process (e.g., an osmotic process, a filtration process, or a combination thereof) on an input (e.g., at least one input stream) and produce an output (e.g., at least one output stream). The membrane separator may comprise at least one semi-permeable membrane defining a permeate side of the membrane separator and a retentate side of the membrane separator. Each membrane separator described herein may include further sub-units such as, for example, individual semi-permeable membrane modules (e.g., in the form of cartridges), valving, fluidic conduits, and the like. As described in more detail below, each membrane separator can include a single semi-permeable membrane or multiple semi-permeable membranes. In some embodiments, a single membrane separator can include multiple sub-units (e.g., multiple modules such as multiple cartridges) that may or may not share a common container.

[0039] The retentate side of the membrane separator may be fluidically connected to one or more components of the aqueous IPA-recovery input stream. For example, the retentate side of the membrane separator (e.g., retentate side 103 in FIG. 1) may be fluidically connected to a source of an aqueous IPA-recovery input stream (e.g., an industrial facility such as a semiconductor processing facility).

[0040] In association with various embodiments, inputs (e.g., the membrane separator retentate input) and outputs (e.g., the membrane separator permeate output, the membrane separator retentate output) are described. In each case the input and / or output may be in the form of a single stream or multiple streams. In some embodiments, it can be advantageous to use a single stream, as opposed to multiple streams. Thus, in some embodiments, the membrane separator retentate input is in the form of a single stream. In certain embodiments, the membrane separator retentate output is in the form of a

[0041] 13191435.1 single stream. In certain embodiments, the membrane separator permeate output is in the form of a single stream.

[0042] In some embodiments, the membrane separator retentate input comprises at least a portion of the aqueous IPA-recovery input stream. In some embodiments, the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) (which may comprise at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the aqueous IPA-recovery input stream, optionally with one or more other streams) is transported to a retentate side of the membrane separator such that a membrane separator retentate output (e.g., a membrane separator retentate output stream) exits the retentate side of the membrane separator, the membrane separator retentate output (e.g., a membrane separator retentate output stream) having a concentration of IPA that is greater (e.g., by a factor of at least 2, at least 3, at least 4, at least 5, at least 10, and / or up to 20, up to 50, up to 100, up to 200, or greater) than the concentration of IPA in the membrane separator retentate input (e.g., a membrane separator retentate inlet stream). For example, referring again to FIG. 1, membrane separator 102 may comprise at least one semi-permeable membrane defining retentate side 103 and permeate side 104, and the membrane separator retentate input in the form of membrane separator retentate inlet stream 105 may be transported to retentate side 103 such that the membrane separator retentate output in the form of membrane separator retentate outlet stream 106 exits retentate side 103. In some embodiments, such as that shown in FIG. 1, the membrane separator retentate input in the form of retentate inlet stream 105 comprises at least a portion of aqueous IPA-recovery input stream 101. This step may be performed such that membrane separator retentate outlet stream 106 has a concentration of IPA that is greater than the concentration of IPA of membrane separator retentate inlet stream 105, according to some embodiments. For example, this step may be performed such that membrane separator retentate outlet stream 106 has a concentration of IPA that is increased with respect to the concentration of membrane separator retentate inlet stream 105 (e.g., by a factor of at least 2, at least 3, at least 4, at least 5, at least 10, and / or up to 20, up to 50, up to 100, up to 200, or greater). In some embodiments, a hydraulic pressure is applied (e.g., to facilitate transport of liquid and / or solute from the retentate side to the permeate side). For example, the hydraulic pressure may be applied the retentate side of the membrane separator during at least a portion of time during

[0043] 13191435.1 which the at least a portion of liquid from the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) is transported from the retentate side of the membrane separator, through the semi-permeable membrane of the membrane separator, to the permeate side of the membrane separator. In some embodiments, the system is operated such that the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) has a hydraulic pressure of at least 200 psi (at least 1.38 x 103kPa), at least 500 psi (at least 3.45 x 103kPa), at least 750 psi (at least 5.17 x 103kPa), at least 1000 psi (at least 6.90 x 103kPa), and / or up to 1500 psi (up to 1.03 x 104kPa), up to 2000 psi (up to 1.38 x 104kPa), or more.

[0044] In some embodiments, at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 90 wt%, up to 95 wt%, up to 99 wt%, or more) of liquid (e.g., water) from the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) is transported from the retentate side of the membrane separator, through a semi-permeable membrane of the membrane separator, to a permeate side of the membrane separator. Referring again to FIG. 1, for example, at least a portion of liquid from membrane separator retentate input in the form of membrane separator retentate inlet stream 105 may be transported from retentate side 103, through a semi-permeable membrane, to permeate side 104. Liquid transported from the retentate side to the permeate side of the membrane separator may form some or all of a membrane separator permeate output (e.g., a membrane separator permeate outlet stream) (e.g., membrane separator permeate outlet stream 107 in FIG. 1), which may be discharged from the system (e.g., as relatively pure liquid such as relatively pure water).

[0045] In some, but not necessarily all embodiments, a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, and / or up to 85 wt%, up to 90 wt%, or more) of IPA from the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) is transported from the retentate side of the membrane separator, through a semi-permeable membrane of the membrane separator, to a permeate side of the membrane separator. However, in some embodiments, little or none (e.g., less than or equal to 10 wt%, less than or equal to 5 wt%, less than or equal to 2 wt%, less than or equal to 1 wt%, less than or equal to 0.1 wt%, or less) of the IPA from the membrane separator retentate input (e.g., a membrane separator retentate inlet stream) is transported from the retentate side of the membrane separator, through a semi-

[0046] 13191435.1 permeable membrane of the membrane separator, to a permeate side of the membrane separator.

[0047] In some embodiments, the membrane separator is operated as an osmotic separator. For example, in some embodiments, the semi-permeable membrane is an osmotic membrane. Transport of solvent (e.g., water) through osmotic membrane(s) of membrane separators can be achieved via a transmembrane net driving force (i.e., a net driving force through the thickness of the membrane(s)), according to certain embodiments. Generally, the transmembrane net driving force (A%) is expressed as:

[0048] AX= AP - A / 7 = (Pi - P2) - ( / 7X- / 72) [1] wherein Pi is the hydraulic pressure on the retentate side of the osmotic membrane, P2 is the hydraulic pressure on the permeate side of the osmotic membrane, Ih is the osmotic pressure of the stream on the retentate side of the osmotic membrane, and Ih is the osmotic pressure of the stream on the permeate side of the osmotic membrane. (Pi - P2 can be referred to as the transmembrane hydraulic pressure difference, and (Th - Ih can be referred to as the transmembrane osmotic pressure difference.

[0049] The osmotic pressure of a particular liquid is an intrinsic property of the liquid. The osmotic pressure can be determined in a number of ways, with the most efficient method depending upon the type of liquid being analyzed. For certain solutions with relatively low molar concentrations of ions, osmotic pressure can be accurately measured using an osmometer. In other cases, the osmotic pressure can simply be determined by comparison with solutions with known osmotic pressures. For example, to determine the osmotic pressure of an uncharacterized solution, one could apply a known amount of the uncharacterized solution on one side of a non-porous, semi-permeable, osmotic membrane and iteratively apply different solutions with known osmotic pressures on the other side of the osmotic membrane until the differential pressure through the thickness of the membrane is zero.

[0050] The osmotic pressure (IT) of a solution containing n solubilized species may be estimated as: n = ^=1ijMjRT [2] wherein z) is the van’t Hoff factor of the jthsolubilized species, Mj is the molar concentration of the jthsolubilized species in the solution, R is the ideal gas constant, and T is the absolute temperature of the solution. Equation [2] generally provides an accurate

[0051] 13191435.1 estimate of osmotic pressure for liquid with low concentrations of solubilized species (e.g., concentrations at or below between about 4 wt% and about 6 wt%). For many liquids comprising solubilized species, at species concentrations above around 4-6 wt%, the increase in osmotic pressure per increase in salt concentration is greater than linear (e.g., slightly exponential).

[0052] As mentioned above, one type of osmotic separation technique that can be performed using the membrane separators of this disclosure, according to some embodiments, is reverse osmosis. Reverse osmosis generally occurs when the osmotic pressure on the retentate side of the osmotic membrane is greater than the osmotic pressure on the permeate side of the osmotic membrane, and a pressure is applied to the retentate side of the osmotic membrane such that the hydraulic pressure on the retentate side of the osmotic membrane is sufficiently greater than the hydraulic pressure on the permeate side of the osmotic membrane such that the osmotic pressure difference is overcome and liquid (e.g., a solvent such as water) is transported from the retentate side of the osmotic membrane to the permeate side of the osmotic membrane. Generally, such situations result when the transmembrane hydraulic pressure difference (P7-P2) is greater than the transmembrane osmotic pressure difference (III .II2) such that liquid (e.g., a solvent such as water) is transported from the retentate side of the osmotic membrane to the permeate side of the osmotic membrane (rather than having liquid be transported from the permeate side of the osmotic membrane to the retentate side of the osmotic membrane, which would be energetically favored in the absence of the pressure applied to the retentate side of the osmotic membrane). In some embodiments, the membrane separator is operated to perform reverse osmosis.

[0053] While FIG. 1 shows a single membrane separator, it should be understood that a different number of membrane separators can be employed in the system and used in the methods of this disclosure. In some embodiments, the membrane separator is a first membrane separator and the system comprises additional membrane separators arranged in series and / or parallel with the first membrane separator. In some embodiments, the system comprises a plurality of membrane separators (e.g., at least two, at least three, at least four, at least five, at least ten, and least twenty, or more membrane separators) configured as described in this disclosure. For example, some embodiments comprise transporting a second membrane separator retentate input (e.g., a second membrane separator retentate inlet stream) to a retentate side of a second membrane separator. The

[0054] 13191435.1 second membrane separator may comprise at least one semi-permeable membrane defining a permeate side of the second membrane separator and a retentate side of the second membrane separator. The second membrane separator retentate input (e.g., a second membrane separator retentate inlet stream) may comprise at least a portion of the first membrane separator retentate output. Moreover, some embodiments comprise transporting a third membrane separator retentate input (e.g., a third membrane separator retentate inlet stream) to a retentate side of a third membrane separator. The third membrane separator may comprise at least one semi-permeable membrane defining a permeate side of the third membrane separator and a retentate side of the third membrane separator. The third membrane separator retentate input (e.g., a membrane separator retentate inlet stream) may comprise at least a portion of the second membrane separator retentate output.

[0055] In some embodiments, a pressure of any of the streams described herein can be increased via one or more additional components, such as one or more booster pumps. In some embodiments, a pressure of any of the streams described herein can be decreased via one or more additional components, such as one or more additional valves and / or energy recovery devices. In some embodiments, a membrane separator described herein further comprises one or more heating, cooling, or other concentration or dilution mechanisms or devices.

[0056] The membrane separators described herein (e.g., the first membrane separator, the second membrane separator, the third membrane separator) can each include a single semi-permeable membrane or a plurality of semi-permeable membranes.

[0057] FIG. 3A is a schematic illustration of membrane separator 400A, in which a single semi-permeable membrane is used to separate permeate side 404 from retentate side 406. Membrane separator 400A can be operated by transporting retentate inlet stream 410 across retentate side 406. At least a portion of a liquid (e.g., a solvent) and, in some instances, solute within retentate inlet stream 410 can be transported across semi-permeable membrane 402 to permeate side 404. This can result in the formation of retentate outlet stream 412, which can include a higher concentration of solute than is contained within retentate inlet stream 410, as well as permeate outlet stream 414. Permeate outlet stream 414 can correspond to the liquid (e.g., solvent) and, in some instances, solute, of retentate inlet stream 410 that was transported from retentate side 406 to permeate side 404.

[0058] 13191435.1 In some embodiments, a membrane separator (e.g., the first membrane separator, the second membrane separator, the third membrane separator) comprises a plurality of semi-permeable membranes connected in parallel. One example of such an arrangement is shown in FIG. 3B. In FIG. 3B, membrane separator 400B comprises three semi- permeable membranes 402A, 402B, and 402C arranged in parallel. Retentate inlet stream 410 is split into three sub-streams, with one sub-stream fed to retentate side 406A of semi-permeable membrane 402A, another sub-stream fed to retentate side 406B of semi-permeable membrane 402B, and yet another sub-stream fed to retentate side 406C of semi-permeable membrane 402C. Membrane separator 400B can be operated by transporting the retentate inlet sub-streams across the retentate sides of the semi- permeable membranes. At least a portion of a liquid (e.g., a solvent), and, in some instances, solute, within retentate inlet stream 410 can be transported across each of semi-permeable membranes 402A, 402B, and 402C to permeate sides 404A, 404B, and 404C, respectively. This can result in the formation of three retentate outlet sub-streams, which can be combined to form retentate outlet stream 412. Retentate outlet stream 412 can include a higher concentration of solute than is contained within retentate inlet stream 410. Permeate outlet stream 414 can also be formed (from three permeate outlet sub-streams). Permeate outlet stream 414 can correspond to the liquid (e.g., solvent), and, in some instances, solute of retentate inlet stream 410 that was transported from retentate sides 406A-406C to permeate sides 404A-404C.

[0059] While FIG. 3B shows three semi-permeable membranes connected in parallel, other embodiments could include 2, 4, 5, or more semi-permeable membranes connected in parallel.

[0060] In some embodiments, a membrane separator (e.g., the first membrane separator, the second membrane separator) comprises a plurality of semi-permeable membranes connected in series. One example of such an arrangement is shown in FIG. 3C. In FIG. 3C, membrane separator 400C comprises three semi-permeable membranes 402A, 402B, and 402C arranged in series. In FIG. 3C, retentate inlet stream 410 is first transported to retentate side 406A of semi-permeable membrane 402A. At least a portion of a liquid (e.g., a solvent), and, in some instances, solute, within retentate inlet stream 410 can be transported across semi-permeable membrane 402A to permeate side 404A of semi- permeable membrane 402A. This can result in the formation of permeate outlet stream 414 and first intermediate retentate stream 440 that is transported to retentate side 406B

[0061] 13191435.1 of semi-permeable membrane 402B. At least a portion of a liquid (e.g., a solvent), and, in some instances, solute, within first intermediate retentate stream 440 can be transported across semi-permeable membrane 402B to permeate side 404B of semi- permeable membrane 402B. This can result in the formation of permeate outlet stream

[0062] 450 and second intermediate retentate stream 441 that is transported to retentate side 406C of semi-permeable membrane 402C. At least a portion of a liquid (e.g., a solvent), and, in some instances, solute within second intermediate retentate stream 441 can be transported across semi-permeable membrane 402C to permeate side 404C of semi- permeable membrane 402C. This can result in the formation of permeate outlet stream

[0063] 451 and retentate outlet stream 412.

[0064] While FIG. 3C shows three semi-permeable membranes connected in series, other embodiments could include 2, 4, 5, or more semi-permeable membranes connected in series.

[0065] For membrane separators comprising a plurality of semi-permeable membranes, parameters such as rejection percentage, recovery, and salt passage percentage at standard conditions for the membrane separators are calculated by performing a mass balance on the entire membrane separator. This means that all initial retentate streams for the membrane separator would be added and considered together, all final permeate outlet streams for the membrane separator would be added and considered together, and all final retentate outlet streams for the membrane separator would be added and considered together. For example, as mentioned above, in FIG. 3B, membrane separator 400B comprises three semi-permeable membranes 402A, 402B, and 402C arranged in parallel. Accordingly, calculation of the composition of the retentate inlet stream of membrane separator 400B for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions for membrane separator 400B would involve taking measurements of retentate inlet stream 410 prior to it being split into the three inlet sub- streams fed to retentate sides 406 A, 406B, and 406C of semi-permeable membranes 402A, 402B, and 402C, respectively. Similarly, calculation of the composition of the retentate outlet stream of membrane separator 400B for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions for membrane separator 400B would involve taking measurements of retentate outlet stream 412, which is a combination of the three outlet sub- streams from retentate sides 406 A, 406B, and 406C from semi-

[0066] 13191435.1 permeable membranes 402A, 402B, and 402C, respectively. Also similarly, calculation of the composition of the permeate outlet stream of membrane separator 400B for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions would involve taking measurements of permeate outlet stream 414, which is a combination of the three outlet sub- streams from permeate sides 404A, 404B, and 404C from semi-permeable membranes 402A, 402B, and 402C, respectively.

[0067] As another example of the calculation of parameters corresponding to a membrane separator comprising a plurality of semi-permeable membranes, reference is made to membrane separator 400C in FIG. 3C. Membrane separator 400C comprises three semi-permeable membranes 402A, 402B, and 402C arranged in series. Accordingly, calculation of the composition of the retentate inlet stream of membrane separator 400C for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions for membrane separator 400C would involve taking measurements of retentate inlet stream 410 prior to it entering semi-permeable membrane 402A because semi-permeable membrane 402A is the initial semi-permeable membrane in the series. Similarly, calculation of the composition of the retentate outlet stream of membrane separator 400C for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions for membrane separator 400C would involve taking measurements of retentate outlet stream 412 exiting semi-permeable membrane 402C because semi-permeable membrane 402C is the final semi-permeable membrane in the series with respect to the retentate outlet streams, thereby making retentate outlet stream 412 the final retentate outlet stream of membrane separator 400C. Calculation of the composition of the permeate outlet stream of membrane separator 400C for the purpose of calculating parameters such as the rejection percentage, recovery, and salt passage percentage at standard conditions would involve taking measurements of a combination of permeate outlet streams 414, 450, and 451 exiting semi-permeable membranes 402A, 402B, and 402C respectively. In addition, in some embodiments, a given membrane separator could include multiple semi-permeable membranes connected in parallel as well as multiple semi-permeable membranes connected in series.

[0068] In some embodiments, the membrane separator comprises a plurality of semi- permeable membranes. In some such embodiments, the plurality of semi-permeable

[0069] 13191435.1 membranes within the membrane separator are connected in series. In some such embodiments, the plurality of semi-permeable membranes within the membrane separator are connected in parallel. In certain embodiments, the membrane separator comprises a plurality of membranes a first portion of which are connected in series and another portion of which are connected in parallel.

[0070] As mentioned above, each membrane separator of the system may comprise at least one semi-permeable membrane. In general, a semi-permeable membrane is a barrier that allows some components of a mixture to pass through while blocking at least some of other components (e.g., blocking all of another component, or reducing the relative rate of permeation of another component). For example, a semi-permeable membrane may block some molecules in a liquid solution from passing through while allowing others to pass through. In some instances, a semi-permeable membrane blocks some molecules and permits other molecules to pass through based on their molecular weight and / or charge. As noted above, a semi-permeable membrane can be used for osmotic processes. For example, the semi-permeable membrane may be an osmotic membrane. An osmotic membrane may be capable of producing an osmotic pressure difference between solutions on either side of the membrane upon application of a hydraulic pressure difference across the two sides of the membrane. For example, if an osmotic membrane is placed between two solutions of identical composition such that there is initially no osmotic pressure difference across the membrane, application of a hydraulic pressure difference across the osmotic membrane may allow for transport of components from one side of the membrane to the other such that an osmotic pressure difference across the two sides of the membrane is established.

[0071] The semi-permeable membrane medium can comprise, for example, a metal, a ceramic, a polymer (e.g., polyamides, polyethylenes, polyesters, poly(tetrafluoroethylene), polysulfones, polycarbonates, polypropylenes, poly(acrylates)), and / or composites or other combinations of these. The semi-permeable membranes generally allow for the selective transport of solvent (e.g., water) through the membrane, where solvent is capable of being transmitted through the membrane while solute (e.g., solubilized species such as solubilized ions) are inhibited from being transported through the membrane. Examples of commercially available semi-permeable membranes that can be used in association with certain of the embodiments described herein include, but are not limited to, those commercially available from Dow Water and

[0072] 13191435.1 Process Solutions (e.g., FilmTec™ membranes), Hydranautics, GE Osmonics, Suez, LG, Toyobo, Microdyn, and Toray Membrane, among others known to those of ordinary skill in the art. One example of a commercially available semi-permeable membrane that may be useful for at least some embodiments is the PRO-LF1 membrane from Hydranautics (a Nitto Group company). The semi-permeable membrane may comprise a material that is resistant to fouling under the conditions of the methods described in this disclosure.

[0073] In some embodiments, the semi-permeable membrane of a membrane separator of this disclosure has an average molecular weight cutoff (MWCO) that is sufficiently high such that a desired amount of liquid and / or solute (and / or type of solute) can pass through during operation of the system. In some embodiments, the semi-permeable membrane of a membrane separator of this disclosure has an average molecular weight cutoff (MWCO) that is sufficiently low such that a desired amount of solute (e.g., IPA) is rejected such that an effective separation is performed. In some embodiments, the semi- permeable membrane(s) of the membrane separator and / or the second membrane separator has an average MWCO of less than or equal to 60 Daltons, less than or equal to 50 Daltons, less than or equal to 30 Daltons, less than or equal to 20 Daltons, or less. Combinations of these ranges (e.g., greater than or equal to 20 Daltons and less than or equal to 60 Daltons) are possible. The average MWCO of a membrane refers to the lowest molecular weight solute in which 90% of the solute is retained by the membrane.

[0074] The average MWCO of the semi-permeable membrane may affect any of a variety of the parameters discussed below, such as solute permeability, salt passage, rejection, and / or recovery.

[0075] The solute (e.g., IPA) permeability of each membrane separator may be chosen based on any of a variety of design criteria such as desired purity of permeate, desired hydraulic pressure to be used, and nature of incoming influent (e.g., solute concentration of incoming influent). The solute permeability of a membrane separator can be calculated from the solute flux through the membrane and the respective concentrations of solute on either side using equation [3] below:

[0076] JS = B(CR- CP) [3]

[0077] In the above equation, Jsrepresents the ion flux, CR represents the concentration of solute on the retentate side of the membrane, Cp represents the concentration of solute on the permeate side of the membrane, and B represents the solute permeability. Solute

[0078] 13191435.1 permeability is dependent on the species of solute in the retentate inlet stream and the concentrations on either side of the membrane.

[0079] In some embodiments in which multiple membrane separators are employed, the solute permeabilities of the membrane separator and the second membrane separator (and, if present a third membrane separator, a fourth membrane separator, or more) during operation of the method are chosen to afford good, consistent performance across all membrane separators by accounting for differences in concentrations of their respective retentate inlet streams.

[0080] Water permeability can be calculated from the water flux, pressure differential and osmotic differential, as shown below in equation [4]:

[0081] Jw = A(AP - An) [4]

[0082] In the above equation [4], Jwrepresents the flux of water through the membrane, AP represents the hydraulic pressure differential across the membrane, An represents the osmotic pressure differential across the membrane, and A represents the water permeability.

[0083] The salt passage percentage at standard conditions of each membrane separator may be chosen based on any of a variety of design criteria such as desired purity of permeate, desired hydraulic pressure to be used, and nature of incoming influent (e.g., concentration of incoming influent). The salt passage percentage at standard conditions of a membrane separator is an intrinsic property of the separator based on the quantity of salt, as a percentage, which passes through the semi-permeable membrane(s) from the retentate side to the permeate side of the membrane separator under defined reference conditions. The salt passage percentage at standard conditions of a membrane separator can be determined using the standardized test described in ASTM D4516-19a.

[0084] In some embodiments in which multiple membrane separators are employed, the salt passages at standard conditions of the first membrane separator and the second membrane separator (and, if present a third membrane separator, a fourth membrane separator, or more) used in in the operation of the method are chosen to afford good, consistent performance across all membrane separators by accounting for differences in concentrations of their respective retentate inlet streams. In some embodiments, the salt passage percentage at standard conditions of the first membrane separator and / or the second membrane separator membrane separator are independently greater than or equal to 0%, greater than or equal to 1%, greater than or equal to 2%, greater than or equal to

[0085] 13191435.1 5%, greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 50%, greater than or equal to 75%, and / or up to 80%, up to 85%, up to 90%, or greater. In some embodiments, the membrane separator has a relatively low salt passage percentage at standard conditions. Such a low salt passage percentage at standard conditions may be useful in embodiments in which the membrane separator is operated as a high-rejection reverse osmosis separator. In some embodiments, the membrane separator has a salt passage percentage at standard conditions of less than or equal to 10%, less than or equal to 5%, less than or equal to 2%, less than or equal to 1%, less than or equal to 0.1%, or less.

[0086] Intrinsic properties of a semi-permeable membrane such as salt passage percentage at standard conditions and / or MWCO can be selected based on supplier specifications for commercially-obtained membranes, by controlling the synthesis of membranes, and / or by physically and / or chemically modifying existing membranes (e.g., commercially obtained membranes).

[0087] The rejection of each membrane separator may be chosen based on any of a variety of design criteria such as desired purity of permeate, desired hydraulic pressure to be used, and nature of incoming influent (e.g., solute concentration of incoming influent). The rejection, R, of a membrane separator can be calculated from CR (the concentration of solute on the retentate side of the membrane) and Cp (the concentration of solute on the permeate side of the membrane) and expressed as a percentage using Equation [5] below:

[0088] R = [1 - (Cp / CR)] * 100 [5]

[0089] In some embodiments in which multiple membrane separators are employed, the rejections (7?) of the first membrane separator and the second membrane separator (and, if present the third membrane separator, the fourth membrane separator, or more) during operation of the method are chosen to afford good, consistent performance across all membrane separators by accounting for differences in concentrations of their respective retentate inlet streams.

[0090] In some embodiments, the rejection for at least one solute (e.g., IPA, or all solutes) (e.g., the solute during the step of transporting the membrane separator retentate input to the retentate side of the membrane separator) of the membrane separator is greater than or equal to 10%, greater than or equal to 15%, greater than or equal to 20%, greater than or equal to 50%, greater than or equal to 75%, greater than or equal to 80%,

[0091] 13191435.1 greater than or equal to 85%, greater than or equal to 90%, greater than or equal to 95%, greater than or equal to 98%, greater than or equal to 99%, or greater. It has been realized that having a relatively high rejection percentage (greater than or equal to greater than or equal to 99%, greater than or equal to 99.7%, greater than or equal to 99.8%, greater than or equal to 99.9%, or greater for at least one solute (e.g., IPA) may facilitate effective separation of IPA from aqueous streams, which may be beneficial in some instances. In some embodiments, the rejection for at least one solute (e.g., IPA, or all solutes) (e.g., the solute during the step of transporting the membrane separator retentate input to the retentate side of the membrane separator) of the membrane separator is less than or equal to 100%, less than or equal to 99.9%, less than or equal to 99%, less than or equal to 95%, less than or equal to 90%, less than or equal to 85%, less than or equal to 80%, less than or equal to 75%, less than or equal to 60%, less than or equal to 50%, or less. Combinations of these ranges (e.g., greater than or equal to 10% and less than or equal to 100%) are possible.

[0092] In some embodiments, the system comprises a distillation apparatus. The distillation apparatus may comprise equipment configured to physically separate at least some of the component substances of a liquid mixture by selectively boiling the mixture and collecting at least a portion of the resulting vapor (e.g., via condensation). In the embodiment shown in FIG. 1, system 100 is configured to transport distillation input 201 comprising at least a portion of membrane separator retentate output 106 to distillation apparatus 200. An output enriched in IPA relative to the aqueous IPA-recovery input stream may be transported out of the distillation apparatus. For example, referring back to FIG. 1, IPA-rich liquid output stream 202 may be transported out of distillation apparatus 200, where it may be subjected to further downstream treatment / processing and / or discharged from the system. The distillation apparatus may be employed to form vapor comprising at least a portion of the IPA from the distillation input.

[0093] Any of a variety of distillation formats may be employed, non-limiting examples of which are described below. In some embodiments, the distillation apparatus is configured to be operated as a batch distillation apparatus. In some embodiments, the distillation is configured to be operated as a continuous distillation apparatus. It has been realized in the context of this disclosure that distillation of inputs comprising IPA at relatively high concentrations (e.g., following membrane separation such as via reverse

[0094] 13191435.1 osmosis) can promote effective and efficient separation of IPA from feeds such as wastewater streams (e.g., from semiconductor processing).

[0095] In some embodiments, the distillation apparatus comprises a distillation vessel. The vapor comprising the IPA referenced above may be formed in the distillation vessel. The distillation vessel may be fluidically connected to a distillation entry and a distillation liquid outlet. For example, in the schematic diagrams shown in FIGS. 2A- 2B, distillation apparatus 200 comprises distillation vessel 203 fluidically connected to distillation entry 209 (e.g., comprising one or more inlets directly or indirectly attached to distillation vessel 203). The distillation vessel may be configured to receive the distillation input via the distillation entry. Further, in the schematic diagrams shown in FIGS. 2A-2B, distillation vessel 203 is fluidically connected to distillation liquid outlet 214. Distillation liquid outlet 214 may comprise one or more outlets directly or indirectly attached to condenser 206, which itself has condenser inlet 208 fluidically connected to distillation vessel vapor outlet 205. The distillation liquid outlet may be configured to output an IPA-rich liquid output stream.

[0096] As used herein, “distillation” refers to a process of purifying a liquid by heating it into a vapor that is then condensed back into a liquid. A “distillation vessel” is a vessel within which distillation is performed. Examples of formats of distillation vessels include, but are not limited to distillation columns, stills, and / or rotating disc vessels. The distillation vessel may comprise one or more trays and / or packing to facilitate the separation of the desired vapor (e.g., rich in IPA) from any remaining liquid (e.g., rich in water). In some embodiments, the distillation vessel is a multistage distillation vessel. For example, the distillation vessel may comprise a multistage distillation column.

[0097] As used herein, a liquid that is “purified” is one that includes that liquid in a higher mass percentage than was contained in the original liquid prior to purification. Purified water, for example, is a liquid that contains water in a higher mass percentage than the original liquid prior to the purification process. Purified liquids can be either completely purified liquids (in which no components other than the purified liquid are present, or components other than the purified liquid are present only in trace amounts), or they can be incompletely purified liquids (in which components other than the purified liquid may still be present, but such components are present in a lesser amount than in the original liquid that was subject to purification).

[0098] 13191435.1 As noted above, in some embodiments the distillation input may comprise at least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or more) of the membrane separator retentate output. Such a distillation input may be transported to the distillation entry via a fluidic connection between the distillation entry and the retentate side of the membrane separator. For example, distillation apparatus 200 in system 100 may be fluidically connected to retentate side 103 of membrane separator 102 via a fluidic connection between distillation entry 209 and retentate side 103.

[0099] Upon receiving distillation input 201 via distillation entry 209, distillation apparatus 200 may be configured to induce vapor comprising the IPA in distillation vessel 203. At least some of the vapor may exit distillation vessel 203 via distillation vessel vapor outlet 205 to form distillation vessel vapor output 204 (e.g., as a gas stream comprising IPA vapor). At least a portion of the vapor output by the distillation vessel may subsequently be condensed, as discussed below.

[0100] In some embodiments, the distillation vessel comprises a distillation column. The distillation column may be in the form of a distillation tower or otherwise. The distillation column may have any of a variety formats, including but not limited to cylindrical (e.g., a vertical cylindrical column).

[0101] In some embodiments, the distillation vessel is configured to induce separation of at least some of the vapor (e.g., comprising IPA) from at least some water from the distillation input via centrifugal force. The centrifugal force may supplement or replace the force from earth’s gravitational field in facilitating the separation of the vapor from the remaining distillation input. In some embodiments, the magnitude of the centrifugal force applied to at least some of the vapor and / or liquid within the distillation vessel is greater than the force from earth’s gravitational field (e.g., by a factor of at least 1.05, at least 1.1, at least 1.2, at least 1.5, at least 2, at least 3, at least 5, and / or up to 10, or more). The centrifugal force may contribute to a greater effective mass transfer area between gas phases and liquid phases within the distillation vessel as compared to distillation vessels that employ only gravity. The centrifugal force may cause a thinning of the liquid membrane, which may reduce mass transfer resistance and increase mixing and / or mass transfer efficiency.

[0102] One non-limiting example of a distillation vessel format that can employ such a centrifugal force is a rotating disc distillation vessel. The rotating disc distillation vessel

[0103] 13191435.1 may comprise a shell that at least partially encloses a rotating disc. The rotating disc may be configured to induce contact between liquid and gas (e.g., heated input gas). The rotation may cause the application of the centrifugal force. In some embodiments, the disc comprises a bed comprising packing. The packing may facilitate contact between gases and liquids within the bed. The disc may be configured to rotate around a central axis within the shell. Gas such as but not limited to steam may be fed into the shell from the distillation vessel gas inlet and then enter the disc near or at an edge of the disc. Distillation input (e.g., a liquid stream comprising IPA) may be fed into the center of the disc. The gas and liquid may form an interface within the disc. Rapid spinning of the disc may contribute to a high specific surface area and mass transfer rate within the disc. Distillation vessel vapor output may exit the disc from a gas outlet, and liquid output may be collected from a distillation vessel liquid outlet. In some embodiments, the disc comprises a bed comprising packing.

[0104] FIG. 2D shows a schematic cross-sectional diagram of an example of a rotating disc vessel configured to apply a centrifugal force. In FIG. 2D, distillation vessel 203 comprises shell 226 enclosing rotating disc 227. Distillation input 201 is transported to distillation entry 209 located above the central axis of rotation of rotating disc 227. Meanwhile, heated gas stream 217 is transported to distillation vessel gas inlet 231 at the side of shell 226 and enters rotating disc 227, where it contacts liquid from distillation input 201 as rotating disc 227 spins. Heated gas stream 217 carries vapor (e.g., comprising IPA) up through central piping 233 and out of distillation vessel vapor outlet 205 as distillation vessel vapor output 204 (e.g., comprising IPA vapor). The direction of flow of gas and / or vapor is shown in FIG. 2D with the hollow arrows. Remaining liquid may be transported out of shell 226 as distillation vessel liquid output 215 exiting distillation vessel liquid outlet 216.

[0105] In some embodiments, the distillation apparatus is configured such that the vapor produced in the distillation vessel (e.g., comprising the IPA) has a relatively low residence time. The low residence time may contribute to efficient separation of the IPA from the water within the column. The residence time of the vapor in the distillation vessel may be determined by, for example, the dimensions of the distillation vessel, the composition of the liquid subjected to the distillation, the flow rate of gases and / or liquids within the distillation apparatus, and / or the temperature profile within the distillation vessel. In some embodiments, the vapor comprising the IPA produced in the

[0106] 13191435.1 distillation vessel has a residence time of less than or equal to 20 minutes, less than or equal to 10 minutes, less than or equal to 5 minutes, and / or as low as 2 minutes, as low as 1 minute, or less. Combinations of these ranges (e.g., greater than or equal to 1 minute and less than or equal to 20 minutes) are possible. The residence time of the vapor in the distillation vessel can be determined by dividing the volume of the distillation vessel occupiable by the vapor by the total volumetric flow rate of the vapor exiting the vessel.

[0107] One non-limiting way in which the relatively low residence time for the vapor can be achieved is by configuring the distillation apparatus as a short-bed distillation apparatus. In a short-bed distillation apparatus, a relatively short distance between the location where vapor is generated and where distillate is collected may be employed. The distillation vessel may be configured to separate at least some of the vapor comprising the IPA from at least some of the water in the distillation input. One nonlimiting way in which the distillation vessel may accomplish such as separation is by having the distillation vessel be configured to perform the separation via centrifugal force, as discussed above.

[0108] The distillation vessel has a height, in accordance with certain embodiments. FIGS. 2A, for example, illustrates height 212 of distillation vessel 203 spanning from first end 210 to second end 211 of distillation vessel 203. In this context, this height refers to the height of the portion of the distillation vessel occupiable by fluid but excludes piping used for expelling liquid output or gaseous output. For example, in FIG. 2D, height 212 of distillation vessel 203 in the form of a rotating disc distillation vessel includes the height of shell 226 but does not include the portion of central piping 233 that extends past shell 226. In some embodiments, the height of the distillation vessel is relatively small. The small height may promote a short residence time for the vapor in the column, which may facilitate efficient separation. In some embodiments, the distillation vessel has a height that is less than or equal to 5 m, less than or equal to 4.5 m, less than or equal to 4 m, less than or equal to 3.5 m, and / or as low as 3 m, as low as 2.5 m, as low as 2 m, or less. Combinations of these ranges (e.g., greater than or equal to 2 m and less than or equal to 5 m) are possible.

[0109] The distillation apparatus may comprise further components generally used in industrial distillation equipment. For example, in some embodiments, the distillation apparatus comprises a boiler configured to supply a heating medium to the distillation

[0110] 13191435.1 vessel. The heating medium may comprise stream, a heated oil, and / or another heat source. As a non-limiting example, referring to FIG. 2C, distillation apparatus 200 may comprise boiler 219. Boiler 219 may be configured to receive, via boiler liquid inlet 230, distillation vessel liquid output 215 exiting distillation vessel liquid outlet 216 near the bottom of distillation vessel 203. Boiler 219 may then heat liquid from distillation vessel liquid output 215 to generate heated gas (e.g., steam generated by boiling the liquid), at least a portion of which may be output from boiler gas outlet 218 as heated gas stream 217. Heated gas stream 217 (e.g., a stream comprising steam) may be transported to distillation vessel 203 via distillation vessel gas inlet 231, where it may facilitate the distillation process. In some embodiments in which a boiler is used, the boiler produces blowdown comprising water, at least a portion of which may be transported to a different component of the system and / or discharged from the system. For example, in FIG. 2C, blowdown 228 may exit blowdown outlet 229 from boiler 219.

[0111] In some embodiments, the distillation apparatus comprises a vacuum source (e.g., a pump) configured to apply a vacuum condition to the distillation vessel (e.g., to promote creation of the two-phase vapor / liquid system for distillation).

[0112] In some embodiments, the distillation apparatus is configured to achieve a temperature profile well-suited for IPA / water separation. For example, the distillation apparatus may be configured to achieve an evaporation temperature at at least one location (e.g., at at least one stage) that is greater than or equal to 86 degrees Celsius, greater than or equal to 100 degrees Celsius, greater than or equal to 108 degrees Celsius, and / or up to 110 degrees Celsius, up to 115 degrees Celsius, up to 120 degrees Celsius, or greater. Combinations of these ranges are possible.

[0113] In some embodiments, the distillation apparatus comprises a condenser fluidically connected to an outlet of the distillation vessel and also fluidically connected to the distillation liquid outlet. The condenser may be configured to induce formation of liquid from the vapor produced by the distillation vessel. The condenser may comprise a surface through which heat exchange may occur. Any of a variety of condenser formats may be employed. In some embodiments, the condenser is a surface condenser. In some embodiments, the condenser is a shell-and-tube condenser. For example, the condenser may be configured to flow coolant through the tube side while vapor to be condensed flows through the shell side of the condenser (or vice versa). Referring again to distillation apparatus 200 in FIGS. 2A-2B, condenser 206 comprises condenser inlet 208

[0114] 13191435.1 fluidically connected to distillation vessel vapor outlet 205 of distillation vessel 203 such that condenser inlet 208 can receive condenser vapor input 207 comprising at least a portion of distillation vessel vapor output 204 exiting distillation vessel outlet vapor 205.

[0115] Condensation of at least a portion of the vapor comprising the IPA in the condenser may produce at least a portion of an IPA-rich liquid output stream. The IPA- rich liquid output stream may comprise at least a portion of the IPA from the vapor produced by the distillation vessel. In some embodiments, the IPA-rich liquid output stream comprises IPA at a concentration greater than a concentration of IPA in the distillation input (e.g., by a factor of greater than or equal to 1.05, greater than or equal to 1.1, greater than or equal to 1.2, greater than or equal to 1.5, greater than or equal to 2, greater than or equal to 5, greater than or equal to 10, greater than or equal to 20, greater than or equal to 50, and / or up to 100, up to 1,000, or greater). In some embodiments, the IPA-rich liquid output stream comprises IPA at a concentration of greater than or equal to 25 wt%, greater than or equal to 40 wt%, greater than or equal to 50 wt%, and / or up to 60 wt%, up to 70 wt%, up to 80 wt%, up to 85 wt%, up to 90 wt%, or greater. Combinations of these ranges are possible.

[0116] The distillation apparatus may be configured such that the IPA-rich liquid output stream exits via the distillation liquid outlet. For example, in FIGS. 2A-2B, distillation apparatus 200 comprises distillation liquid outlet 214 fluidically connected to condenser 206 (e.g., directly or indirectly fluidically connected) and configured such that IPA-rich liquid output stream 202 comprising IPA condensed in condenser 206 exits distillation apparatus 200.

[0117] In some embodiments, the distillation apparatus comprises a reflux drum configured to receive at least a portion of liquid formed in the condenser. In some embodiments, a first portion of liquid exiting the reflux drum is supplied back to the distillation vessel (e.g., for reflux) and a second portion of the liquid, the distillate, forms some or all of the IPA-rich liquid output stream. For example, referring back to FIG. 2C, distillation apparatus 200 may comprise reflux drum 220. Condenser liquid output 221 may exit condenser liquid outlet 222, and at least a portion of condenser liquid output 221 may be transported to reflux drum 220 via condenser liquid inlet 223. In some embodiments, reflux 224 comprising a first portion of condenser liquid output 221 may exit reflux outlet 225 of reflux drum 220, and reflux 224 may be transported back to distillation vessel 203 via distillation vessel reflux inlet 232. A second portion of

[0118] 13191435.1 condenser liquid output 221 may exit distillation liquid outlet 214 as distillate that forms at least a portion of IPA-rich liquid output stream 202. While FIG. 2C shows reflux 224 and IPA-rich liquid output stream 202 as exiting reflux drum 220 from different outlets, such an arrangement is non-limiting. For example, in some embodiments a single liquid output exits the reflux drum and is split into the respective reflux and distillate portions, the latter forming at least some of the IPA-rich liquid output stream.

[0119] In some embodiments, the distillation input is configured such that any azeotropes that may be formed between the IPA and water are broken. IPA forms a homogenous minimum-boiling azeotrope with water at 87.8 wt%, with the azeotrope having a boiling point of 80.3 degrees Celsius. This azeotrope can present difficulties for using distillation to separate IPA and water. In some embodiments, an IPA- water- azeotrope-breaking agent is employed in the distillation input. The IPA-water- azeotrope-breaking agent may induce a breaking of the azeotrope such that IPA can be separated at higher concentrations than would be afforded in situations in which the IPA- water-azeotrope-breaking agent is not present. Any of a variety of IPA-water-azeotrope- breaking agents may be employed, including, but not limited to, IPA-water-azeotrope- breaking agents comprising salts (e.g., sodium salts such as sodium chloride), organic species (e.g., di-isopropyl ether, dimethylsulfoxide, ethylene glycol, methyl-2- pyrrolidone, methyl-2-piperidone, methyl-6-caprolactam), and / or ionic liquids (e.g., 1- ethyl-3-methylimidazolium dicyanamide). In some embodiments, the IPA- water- azeotrope-breaking agent is combined with other streams such as those of the membrane separator retentate output to form some or all of the distillation input prior to the distillation input entering the distillation vessel. For example, in FIG. 2B, membrane separator retentate outlet stream 106 is combined with IPA-water-azeotrope-breaking agent 213 to form distillation input 201. However, in some embodiments, the IPA- water-azeotrope-breaking agent may be combined with the IPA / water mixture within the distillation vessel rather than prior to entry to the distillation vessel.

[0120] As used herein, two elements are in fluidic communication with each other (or, equivalently, in fluid communication with each other) when fluid may be transported from one of the elements to the other of the elements without otherwise altering the configurations of the elements or a configuration of an element between them (such as a valve). Two conduits connected by an open valve (thus allowing for the flow of fluid between the two conduits) are considered to be in fluidic communication with each

[0121] 13191435.1 other. In contrast, two conduits separated by a closed valve (thus preventing the flow of fluid between the conduits) are not considered to be in fluidic communication with each other.

[0122] As used herein, two elements are fluidically connected to each other when they are connected such that, under at least one configuration of the elements and any intervening elements, the two elements are in fluidic communication with each other. Two membrane separators connected by a valve and conduits that permit flow between the membrane separators in at least one configuration of the valve would be said to be fluidically connected to each other. To further illustrate, two membrane separators that are connected by a valve and conduits that permit flow between the membrane separators in a first valve configuration but not a second valve configuration are considered to be fluidically connected to each other both when the valve is in the first configuration and when the valve is in the second configuration. In contrast, two membrane separators that are not connected to each other (e.g., by a valve, another conduit, or another component) in a way that would permit fluid to be transported between them under any configuration would not be said to be fluidically connected to each other. Elements that are in fluidic communication with each other are always fluidically connected to each other, but not all elements that are fluidically connected to each other are necessarily in fluidic communication with each other.

[0123] Various components are described herein as being fluidically connected. Fluidic connections may be either direct fluidic connections or indirect fluidic connections. Generally, a direct fluidic connection exists between a first region and a second region (and the two regions are said to be directly fluidically connected to each other) when they are fluidically connected to each other and when the composition of the fluid at the second region of the fluidic connection has not substantially changed relative to the composition of the fluid at the first region of the fluidic connection (i.e., no fluid component that was present in the first region of the fluidic connection is present in a weight percentage in the second region of the fluidic connection that is more than 5% different from the weight percentage of that component in the first region of the fluidic connection). As an illustrative example, a stream that connects first and second unit operations, and in which the pressure and temperature of the fluid is adjusted but the composition of the fluid is not altered, would be said to directly fluidically connect the first and second unit operations. If, on the other hand, a separation step is performed

[0124] 13191435.1 and / or a chemical reaction is performed that substantially alters the composition of the stream contents during passage from the first unit operation to the second unit operation, the stream would not be said to directly fluidically connect the first and second unit operations. In some embodiments, a direct fluidic connection between a first region and a second region can be configured such that the fluid does not undergo a phase change from the first region to the second region. In some embodiments, the direct fluidic connection can be configured such that at least 50 wt% (or at least 75 wt%, at least 90 wt%, at least 95 wt%, or at least 98 wt%) of the fluid (e.g., liquid) in the first region is transported to the second region via the direct fluidic connection. Any of the fluidic connections described herein may be, in some embodiments, direct fluidic connections. In other cases, the fluidic connections may be indirect fluidic connections.

[0125] The following applications are incorporated herein by reference, in their entirety, for all purposes: U.S. Patent Application Publication No. US 2015 / 0060286 published on March 5, 2015, filed as U.S. Patent Application No. 14 / 452,387 on August 5, 2014, and entitled “WATER TREATMENT SYSTEMS AND ASSOCIATED METHODS”; U.S. Patent Application Publication No. US 2015 / 0129410 published on May 14, 2015, filed as U.S. Patent Application No. 14 / 485,606 on September 12, 2014, and entitled “SYSTEMS INCLUDING A CONDENSING APPARATUS SUCH AS A BUBBLE COLUMN CONDENSER”; U.S. Patent Application Publication No. US 2015 / 0083577 published on March 26, 2015, filed as U.S. Patent Application No. 14 / 494,101 on September 23, 2014, and entitled “DESALINATION SYSTEMS AND ASSOCIATED METHODS”; U.S. Patent Application Publication No. US 2016 / 0228795 published on August 11, 2016, filed as U.S. Patent Application No. 14 / 719,295 on May 21, 2015, and entitled “METHODS AND SYSTEMS FOR PRODUCING TREATED BRINES”; U.S. Patent Application Publication No. US 2019 / 0009218 published on January 10, 2019, filed as U.S. Patent Application No. 15 / 747,907 on January 26, 2018, and entitled “OSMOTIC DESALINATION METHODS AND ASSOCIATED SYSTEMS”; U.S. Patent Application Publication No. US 2017 / 0144906 published on May 25, 2017, filed as U.S. Patent Application No. 15 / 364,785 on November 30, 2016, and entitled “SYSTEMS AND METHODS FOR TREATMENT OF WATER, SUCH AS OILFIELD WASTEWATER, VIA CHEMICAL COAGULATION”; U.S. Patent Application Publication No. US 2021 / 0179452 published on June 17, 2021, filed as U.S. Patent Application No. 17 / 270,142 on February 22, 2021, and entitled “LIQUID SOLUTION

[0126] 13191435.1 CONCENTRATION SYSTEM COMPRISING ISOLATED SUBSYSTEM AND RELATED METHODS”; U.S. Patent Application Publication No. US 2022 / 0380233 published on December 1, 2022, filed as U.S. Patent Application No. 17 / 882,701 on August 8, 2022, and entitled “OSMOTIC METHODS AND SYSTEMS INVOLVING ENERGY RECOVERY”; U.S. Patent Application Publication No. US 2024 / 0109037 published on April 4, 2024, filed as U.S. Patent Application No. 18 / 315,130 on May 10, 2023, and entitled “LIQUID SEPARATION USING SOLUTE-PERMEABLE MEMBRANES AND RELATED SYSTEMS”; and U.S. Patent Application Publication No. 2023 / 0001355, published on January 5, 2023, filed as U.S. Patent Application No. 17 / 305,289 on July 2, 2021, and entitled “MEMBRANES WITH CONTROLLED POROSITY FOR SERIAL FILTRATION.”

[0127] The following examples are intended to illustrate certain embodiments of the present invention, but do not exemplify the full scope of the invention.

[0128] EXAMPLE 1

[0129] This Example provides experimental data demonstrating the use of a membrane separator in the form of a reverse osmosis unit to enrich the IPA content in an aqueous stream. FIG. 4 is a data plot showing total organic carbon (TOC) for a membrane separator retentate output (Cone. TOC) and a membrane separator permeate output (Perm. TOC) versus concentration factor for experiments in which an aqueous stream comprising IPA was fed to a reverse osmosis unit, according to some embodiments. The concentration factor used for the X-axis of the data series corresponds to the ratio of the TOC in the membrane separator retentate output divided by the TOC in the membrane separator retentate input for the experiments that generated the data points. The data indicates significant enhancement in IPA content (as indicated by enhanced TOC) in the reverse osmosis unit’s retentate output both as a function of concentration factor and as compared to the content in the reverse osmosis unit’s permeate output. This indicates that a membrane separator can effectively concentrate IPA from aqueous streams and separate it from water.

[0130] While several embodiments of the present invention have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and / or structures for performing the functions and / or obtaining the results and / or one or more of the advantages described herein, and each of such variations and / or modifications is deemed to be within the scope of the present invention. More generally,

[0131] 13191435.1 those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and / or configurations will depend upon the specific application or applications for which the teachings of the present invention is / are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, the invention may be practiced otherwise than as specifically described and claimed. The present invention is directed to each individual feature, system, article, material, and / or method described herein. In addition, any combination of two or more such features, systems, articles, materials, and / or methods, if such features, systems, articles, materials, and / or methods are not mutually inconsistent, is included within the scope of the present invention.

[0132] As used herein in the specification and in the claims, the phrase “at least a portion” means some or all. “At least a portion” may mean, in accordance with certain embodiments, at least 1 wt%, at least 2 wt%, at least 5 wt%, at least 10 wt%, at least 25 wt%, at least 50 wt%, at least 75 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt%, and / or, in certain embodiments, up to 100 wt%.

[0133] The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.”

[0134] The phrase “and / or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Other elements may optionally be present other than the elements specifically identified by the “and / or” clause, whether related or unrelated to those elements specifically identified unless clearly indicated to the contrary. Thus, as a non-limiting example, a reference to “A and / or B,” when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A without B (optionally including elements other than B); in another embodiment, to B without A (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

[0135] 13191435.1 As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and / or” as defined above. For example, when separating items in a list, “or” or “and / or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of’ or “exactly one of,” or, when used in the claims, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e. “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” when used in the claims, shall have its ordinary meaning as used in the field of patent law.

[0136] As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and / or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

[0137] Unless clearly indicated to the contrary, concentrations and percentages described herein are on a mass basis.

[0138] As used herein, “wt%” is an abbreviation of weight percentage. As used herein, “at%” is an abbreviation of atomic percentage.

[0139] Some embodiments may be embodied as a method, of which various examples have been described. The acts performed as part of the methods may be ordered in any

[0140] 13191435.1 suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include different (e.g., more or less) acts than those that are described, and / or that may involve performing some acts simultaneously, even though the acts are shown as being performed sequentially in the embodiments specifically described above.

[0141] Use of ordinal terms such as “first,” “second,” “third,” etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.

[0142] In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of’ and “consisting essentially of’ shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.

[0143] 13191435.1

Claims

CLAIMSWhat is claimed is:

1. A method for separating isopropyl alcohol (IPA) from an aqueous IPA-recovery input stream, comprising: transporting a membrane separator retentate input comprising at least a portion of the aqueous IPA-recovery input stream comprising IPA to a retentate side of a membrane separator such that: a membrane separator retentate output exits the retentate side of the membrane separator, the membrane separator retentate output having a concentration of IPA that is greater than a concentration of IPA in the membrane separator retentate input, and at least a portion of water from the membrane separator retentate input is transported from the retentate side of the membrane separator, through a semi- permeable membrane of the membrane separator, to a permeate side of the membrane separator; transporting a distillation input comprising at least a portion of the membrane separator retentate output to a distillation apparatus; forming a vapor comprising at least a portion of the IPA from the distillation input in a distillation vessel of the distillation apparatus; and condensing at least a portion of the vapor to form at least a portion of an IPA-rich liquid output stream comprising IPA at a concentration greater than a concentration of IPA in the distillation input; wherein:(a) the distillation vessel has a height that is less than or equal to 5 m, and / or(b) the vapor has a residence time in the distillation vessel of less than or equal to 20 minutes.

2. A method for separating isopropyl alcohol (IPA) from an aqueous IPA-recovery input stream, comprising:13191435.1transporting a membrane separator retentate input comprising at least a portion of the aqueous IPA-recovery input stream comprising IPA to a retentate side of a membrane separator such that: a membrane separator retentate output exits the retentate side of the membrane separator, the membrane separator retentate output having a concentration of IPA that is greater than a concentration of IPA in the membrane separator retentate input, and at least a portion of water from the membrane separator retentate input is transported from the retentate side of the membrane separator, through a semi- permeable membrane of the membrane separator, to a permeate side of the membrane separator; transporting a distillation input comprising at least a portion of the membrane separator retentate output to a distillation apparatus; forming a vapor comprising at least a portion of the IPA from the distillation input in a distillation vessel of the distillation apparatus, wherein the distillation apparatus induces separation of at least some of the vapor from at least some water from the distillation input via centrifugal force; and condensing at least a portion of the vapor to form at least a portion of an IPA-rich liquid output stream comprising IPA at a concentration greater than a concentration of IPA in the distillation input.

3. The method of any one of claims 1-2, wherein the distillation vessel has a height that is less than or equal to 5 m.

4. The method of any one of claims 1-3, wherein, the height is greater than or equal to 2 m.

5. The method of any one of claims 1-4, wherein the vapor has a residence time in the distillation vessel of less than or equal to 20 minutes.

6. The method of any one of claims 1-5, wherein the vapor has a residence time in the distillation vessel of greater than or equal to 1 minute.13191435.

17. The method of any one of claims 1-6, wherein the distillation apparatus is a shortbed distillation apparatus.

8. The method of any one of claims 1-7, wherein the distillation vessel comprises a distillation column.

9. The method of any one of claims 1 and 3-8, wherein the distillation apparatus induces separation of at least some of the vapor from at least some water from the distillation input via centrifugal force.

10. The method of any one of claims 1-9, wherein the distillation input further comprises an IPA-water-azeotrope-breaking agent.

11. The method of claim 10, wherein the IPA-water-azeotrope-breaking agent comprises a salt.

12. The method of claim 11, wherein the salt comprises a sodium salt.

13. The method of any one of claims 1-12, wherein the condensing is performed in a condenser fluidically connected to an outlet of the distillation vessel.

14. The method of any one of claims 1-13, wherein the aqueous IPA-recovery input stream is or is derived from a wastewater stream.

15. The method of claim 14, wherein the wastewater stream is a semiconductor processing waste water stream.

16. The method of any one of claims 1-15, wherein the aqueous IPA-recovery input stream comprises IPA in an amount of greater than or equal to 2,000 mg / L.

17. The method of any one of claims 1-16, wherein the aqueous IPA-recovery input stream comprises IPA in an amount of less than or equal to 20,000 mg / L.13191435.

118. The method of any one of claims 1-17, wherein the semi-permeable membrane has an average MWCO of less than or equal to 60 Daltons.

19. The method of any one of claims 1-18, wherein the membrane separator has a rejection for at least one solute of greater than or equal to 99%.

20. The method of any one of claims 1-19, further comprising applying a hydraulic pressure to the membrane separator retentate input.

21. The method of any one of claims 1-20, wherein the membrane separator is operated at a reverse osmosis unit.

22. A system for separating isopropyl alcohol (IPA) from an aqueous IPA-recovery input stream, comprising: a membrane separator comprising at least one semi-permeable membrane defining a retentate side of the membrane separator and a permeate side of the membrane separator, wherein the retentate side of the membrane separator is configured to: receive a membrane separator retentate input comprising at least a portion of the aqueous IPA-recovery input stream comprising IPA, and output a membrane separator retentate output having a higher concentration of IPA than the membrane separator retentate input; and a distillation apparatus comprising: a distillation entry fluidically connected to the retentate side of the membrane separator and configured to receive a distillation input; a distillation liquid outlet configured to output an IPA-rich liquid output stream; and a distillation vessel fluidically connected to the distillation entry and the distillation liquid outlet, wherein the distillation vessel has a height along that is less than or equal to 5 m.

23. A system for separating isopropyl alcohol (IPA) from an aqueous IPA-recovery input stream, comprising:13191435.1a membrane separator comprising at least one semi-permeable membrane defining a retentate side of the membrane separator and a permeate side of the membrane separator, wherein the retentate side of the membrane separator is configured to: receive a membrane separator retentate input comprising at least a portion of the aqueous IPA-recovery input stream comprising IPA, and output a membrane separator retentate output having a higher concentration of IPA than the membrane separator retentate input; and a distillation apparatus comprising: a distillation entry fluidically connected to the retentate side of the membrane separator and configured to receive a distillation input; a distillation liquid outlet configured to output an IPA-rich liquid output stream; and a distillation vessel fluidically connected to the distillation entry and the distillation liquid outlet, wherein the distillation apparatus is configured to induce separation of at least some of vapor from at least some water from the distillation input via centrifugal force.

24. The system of claim 22, wherein the height is greater than or equal to 2 m.

25. The system of any one of claims 22-24, wherein the distillation apparatus is a short-bed distillation apparatus.

26. The system of any one of claims 22-25, wherein the distillation vessel comprises a distillation column.

27. The system of any one of claims 22 and 24-26, wherein the distillation apparatus is configured to induce separation of at least some IPA from at least some water from the distillation input via centrifugal force.

28. The system of any one of claims 22-27, wherein the distillation input further comprises an IPA-water-azeotrope-breaking agent.13191435.

129. The system of any one of claims 22-28, wherein the IPA-water-azeotrope- breaking agent comprises a salt.

30. The system of any one of claims 22-29, wherein the salt comprises a sodium salt.

31. The system of any one of claims 22-30, wherein the distillation apparatus comprises a condenser fluidically connected to an outlet of the distillation vessel and the distillation liquid output.

32. The system of any one of claims 22-31, wherein the retentate side of the membrane separator is fluidically connected to a source of the aqueous IPA-recovery input stream.

33. The system of claim 32, wherein the aqueous IPA-recovery input stream is or is derived from a wastewater stream.

34. The system of claim 33, wherein the wastewater stream is a semiconductor processing waste water stream.

35. The system of any one of claims 32-34, wherein the aqueous IPA-recovery input stream comprises IPA in an amount of greater than or equal to 2,000 mg / L.

36. The system of any one of claims 32-35, wherein the aqueous IPA-recovery input stream comprises IPA in an amount of less than or equal to 20,000 mg / L.

37. The system of any one of claims 22-36, wherein the at least one semi-permeable membrane has an average MWCO of less than or equal to 60 Daltons.13191435.1

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