Membrane-based separation of micellar associated pfas molecules

Abstract

Certain aspects of the present disclosure relate to systems and methods related to removal of PFAS molecules. In one aspect, a system including a membrane separator and a foam fractionating separator is generally described. In some embodiments, the membrane separator and the foam fractionating separator are fluidly connected such that a portion or all of a feed comprising PFAS molecules, surfactant, and liquid and / or a portion or all of a foam fractionating separator input comprising PFAS molecules and liquid may be treated by the membrane separator and / or the foam fractionating separator. In some embodiments, at least a portion of the PFAS molecules are removed from the feed and / or foam fractionating separator input. In some embodiments, the surfactant is present such that a portion or all of the PFAS molecules are associated with micelles, which may facilitate removal of the PFAS molecules from the feed and / or foam fractionating separator inputs. In some embodiments, the membrane separator intercepts PFAS molecules (e.g., PFAS molecules associated with micelles) to a greater extent than certain dissolved ions.

Description

[0001] Related applications

[0002] This application is based on 35 USC 119(e) claims priority to U.S. Provisional Patent Application No. 63 / 645,798, filed May 10, 2024, entitled “Membrane-Based Separation of Micelle-Associated PFAS Molecules,” which is incorporated herein by reference in its entirety for all purposes. Technical Field

[0003] Systems and methods for removing perfluoroalkyl and / or polyfluoroalkyl substances (PFAS) are generally described. Background Technology

[0004] Perfluoroalkyl substances (PFAS) and / or polyfluoroalkyl substances (PFAS) cause health and environmental problems. Therefore, improved methods and related systems for treating mixtures containing PFAS are desired. Summary of the Invention

[0005] Systems and methods for removing perfluoroalkyl substances and / or polyfluoroalkyl substances (PFAS) are generally described. In some cases, the subject matter of this disclosure relates to related products, alternative solutions to specific problems, and / or multiple different uses of one or more systems and / or articles.

[0006] In one aspect, a system for removing perfluoroalkyl substances and / or polyfluoroalkyl substances (PFAS) is provided.

[0007] In some embodiments, the system includes: a membrane separator comprising at least one semipermeable membrane defining a permeate side and a residual side of the membrane separator, wherein the residual side of the membrane separator is configured to receive a membrane separator residual input comprising perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, a liquid, and a surfactant; and a foam grading separator comprising: an inlet fluidly connected to the permeate side of the membrane separator and configured to receive a foam grading separator input; and one or more outlets configured to: output a foam grading product output having a PFAS molecule concentration lower than that of the foam grading separator input, and output a foam grading recovery output comprising at least some of the PFAS molecules and at least some of the surfactants.

[0008] In some embodiments, the system includes: a membrane separator comprising at least one semipermeable membrane defining a permeate side and a residual side of the membrane separator, wherein the residual side of the membrane separator is configured to receive a membrane separator residual input comprising at least a portion of foam grading recovery output, the foam grading recovery output comprising perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, a liquid, and a surfactant; and a foam grading separator comprising: one or more inlets configured to receive the foam grading separator input; and one or more outlets configured to output foam grading product output with a PFAS molecule concentration lower than that of the foam grading separator input, and output foam grading recovery output.

[0009] In some embodiments, the system includes: a membrane separator comprising at least one semipermeable membrane and configured to: receive a membrane separator residue input containing perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, a surfactant, and a liquid; and remove at least a portion of the PFAS molecules from the membrane separator residue input.

[0010] In another aspect, methods for removing perfluoroalkyl substances and / or polyfluoroalkyl substances (PFAS) are provided.

[0011] In some embodiments, the method includes: removing a quantity of PFAS molecules from a feed comprising a liquid and perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, wherein the removal comprises: conveying a membrane separator permeate input to the permeate side of a membrane separator, the membrane separator permeate input comprising at least a portion of the feed and a surfactant, the presence of the surfactant causing at least some of the PFAS molecules to associate with micelles containing the surfactant, such that: a membrane separator permeate output exits from the permeate side of the membrane separator, and at least a portion of the liquid from the membrane separator permeate input is conveyed from the permeate side of the membrane separator through a semipermeable membrane of the membrane separator to the permeate side of the membrane separator to form a portion or all of the membrane separator permeate output having a PFAS molecule concentration less than the PFAS molecule concentration in the membrane separator permeate input; wherein the membrane separator permeate input comprises at least a portion of the membrane separator permeate output, the membrane separator permeate output comprising at least some of the PFAS molecules conveyed to the permeate side of the membrane separator.

[0012] In some embodiments, the method includes contacting a membrane separator effluent input containing a liquid and molecules of perfluoroalkyl and / or polyfluoroalkyl substances (PFAS) associated with micelles containing a surfactant to a semipermeable membrane, such that at least a portion of the PFAS is removed from the liquid and a membrane separator effluent output is formed.

[0013] Other advantages and novel features of this disclosure will become apparent from the following detailed description of various non-limiting embodiments of this disclosure when considered in conjunction with the accompanying drawings. In the event of conflicting and / or inconsistent disclosures in this specification and in referenced documents, this specification shall prevail. Attached Figure Description

[0014] Non-limiting embodiments of this disclosure will be described by way of example with reference to the accompanying drawings. Unless otherwise stated, the drawings are schematic and not intended to be drawn to scale. In the drawings, each identical or substantially identical component shown is generally represented by a single number. For clarity, not every component is labeled in each drawing, nor is every component of each embodiment of this disclosure shown, unless illustration is required to enable those skilled in the art to understand this disclosure. In the drawings:

[0015] Figure 1A A schematic diagram of a system including a foam grading separator and a membrane separator according to some embodiments is shown.

[0016] Figure 1B A schematic diagram of a system comprising a foam grading separator and a membrane separator for receiving at least a portion of the foam grading recycled output is shown according to some embodiments.

[0017] Figure 1C This is a schematic diagram illustrating a system comprising a foam grading separator, a membrane separator, and a container according to some embodiments.

[0018] Figure 1D A schematic diagram of a system comprising a foam grading separator, a membrane separator, and a container for receiving at least a portion of the foam grading recycled output is shown according to some embodiments.

[0019] Figure 2A A schematic diagram of a system according to some embodiments is shown, comprising a foam grading separator for receiving foam grading input and a membrane separator for receiving at least a portion of foam grading recycled output.

[0020] Figure 2BA schematic diagram is provided for a system according to some embodiments, including a foam grading separator for receiving foam grading input, a container for receiving at least a portion of foam grading recovery output and a membrane separator for receiving at least a portion of membrane separator residual output, and a membrane separator.

[0021] Figure 3 The diagram illustrates a system including a membrane separator input for receiving membrane separator residue according to some embodiments, the membrane separator residue input comprising at least a portion of the feed and at least a portion of the membrane separator residue output.

[0022] Figure 4A A schematic diagram of a membrane separator comprising a single semipermeable membrane is shown according to some embodiments.

[0023] Figure 4B A schematic diagram is shown illustrating three semipermeable membranes in parallel fluid connection according to some embodiments.

[0024] Figure 4C A schematic diagram is shown illustrating three semi-permeable membranes connected in series according to some embodiments.

[0025] Figure 5 A schematic diagram is provided illustrating a membrane separator configured to receive an input containing a cationic surfactant, according to some embodiments.

[0026] Figure 6 This is a schematic diagram illustrating a membrane separator configured to recycle and / or retain at least a portion of the permeate output according to some embodiments.

[0027] Figure 7 This is a schematic diagram illustrating a membrane separator in fluid communication with a container (e.g., an EQ tank) according to some embodiments.

[0028] Figure 8 This is a schematic diagram illustrating a system including a foam grading separator upstream of a membrane separator according to some embodiments.

[0029] Figure 9 This is a schematic diagram illustrating a system including a foam grading separator downstream of a membrane separator, according to some embodiments.

[0030] Figure 10 This is a schematic diagram illustrating two semi-permeable membranes connected in series via a membrane separator permeate output, according to some embodiments.

[0031] Figure 11 This is a schematic diagram illustrating two semi-permeable membranes connected in series via a membrane separator permeate outlet, according to some embodiments.

[0032] Figure 12 A schematic diagram illustrating two semipermeable membranes according to some embodiments is provided, the two semipermeable membranes being fluidly connected in series such that an anionic surfactant is introduced before the first semipermeable membrane and a cationic surfactant is subsequently introduced before the second semipermeable membrane.

[0033] Figure 13A A graph was created to depict the percentage of retention of perfluorobutanoic acid (PFBA) by a semipermeable membrane at different surfactant concentrations according to several embodiments.

[0034] Figure 13B A graph was plotted to show the percentage retention of sulfate by fitting a logarithmic trend line of the semipermeable membrane at different surfactant concentrations according to some implementation schemes.

[0035] Figure 13C A graph was created to depict the percentage of retention of perfluorononanoic acid (PFNA) by a semipermeable membrane at different surfactant concentrations according to several embodiments.

[0036] Figure 13D A graph was created to depict the percentage of retention of perfluorooctanoic acid (PFOA) by a semipermeable membrane at different surfactant concentrations according to several embodiments.

[0037] Figure 13E A graph was plotted to show the percentage of retention of perfluorooctanesulfonic acid (PFOS) by a semipermeable membrane at different surfactant concentrations according to several embodiments.

[0038] Figure 13F A graph was plotted to show the percentage of retention of perfluorobutanesulfonic acid (PFBS) by a semipermeable membrane at different surfactant concentrations according to several embodiments.

[0039] Figure 13G A graph was created to depict the percentage of retention rate of perfluorohexanesulphonic acid (PFHxS) by fitting a logarithmic trend line to a semipermeable membrane at different surfactant concentrations according to several embodiments. Detailed Implementation

[0040] Certain aspects of this disclosure relate to systems and methods associated with the removal of PFAS molecules. In one aspect, a system comprising a membrane separator is generally described. In some embodiments, the system comprises a membrane separator and a foam grading separator. In some embodiments, the membrane separator and the foam grading separator are fluidly connected such that a portion or all of a feed containing PFAS molecules and liquid can be processed by the membrane separator and / or the foam grading separator. In some embodiments, at least a portion of the PFAS molecules is removed from the membrane separator residue input and / or the foam grading separator input. In some embodiments, a surfactant is present such that a portion or all of the PFAS molecules associate with micelles, which can promote the removal of PFAS molecules from the feed and / or the foam grading separator input.

[0041] Perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules are known to contaminate parts of the environment, including agricultural applications, industrial applications, and water sources. For clarity, “PFAS” will be used herein to refer to perfluoroalkyl and / or polyfluoroalkyl substances. PFAS may include one or more perfluoroalkyl substances without any polyfluoroalkyl substances, one or more polyfluoroalkyl substances without any perfluoroalkyl substances, or one or more perfluoroalkyl substances and one or more polyfluoroalkyl substances. PFAS molecules are generally difficult to remove from liquid sources (e.g., water sources), especially those with relatively short alkyl chains. Primary, secondary, and / or tertiary foam classification processes can facilitate the removal of PFAS molecules from liquids by concentrating PFAS molecules in the foam before destruction. However, when one or more foam classification steps are used to concentrate PFAS molecules, liquefying the foam for subsequent treatment can be challenging. This problem often becomes even more challenging at high PFAS concentrations. Therefore, there is a need to remove concentrated PFAS molecules from the liquid for subsequent destruction. As recognized in the context of this disclosure, the use of membrane separators and surfactants can facilitate the removal of PFAS molecules. In some embodiments, the surfactant forms micelles that associate with PFAS molecules and can be removed and / or concentrated by the membrane separator. In some embodiments, the removal of PFAS molecules by a membrane separator can replace one or more foam classification processes because the membrane separator can allow for a concentrated stream (e.g., a liquid stream) of PFAS molecules to be supplied for subsequent destruction processes.

[0042] According to certain embodiments, the systems and methods described in this disclosure relate to the removal of PFAS molecules. Generally, some embodiments relate to systems including a membrane separator configured to receive a membrane separator input comprising PFAS molecules, a surfactant, and a liquid, and to remove at least a portion of the PFAS molecules from the membrane separator input (and thus, according to some embodiments, the feed). Various methods can be used to achieve this, examples of which can be found in this disclosure. Generally, some embodiments relate to methods comprising contacting a solution containing PFAS molecules associated with micelles comprising a surfactant to a semipermeable membrane, such that at least a portion of the PFAS is removed from the solution. Many ways in which this can be achieved are described in this disclosure.

[0043] In some embodiments, PFAS molecules are removed from the membrane separator permeate feed or foam classification separator feed, as described in more detail elsewhere in this disclosure. To facilitate the removal of PFAS molecules, a surfactant may be provided. In some embodiments, a surfactant is provided such that at least some of the PFAS molecules associate with a micelle containing the surfactant. Any of a variety of surfactants may be suitable for this purpose. In some embodiments, micelles advantageously facilitate the removal of PFAS molecules when they are introduced into a fluid device such as a membrane separator and / or a foam classification separator. Micelles may allow the membrane separator and / or foam classification separator to concentrate PFAS molecules in one or more outputs such that the concentration of PFAS molecules in one or more outputs is higher than the concentration of PFAS molecules in the feed and / or foam classification separator input. According to some embodiments, an unexpectedly low concentration of surfactant may be required for PFAS molecules to associate with the surfactant to form micelles. In some embodiments, the foam classification separator may receive part or all of the membrane separator permeate output from the membrane separator for further removal of any remaining PFAS molecules. In some implementations, the membrane separator can receive part or all of the foam grading recovery output leaving the foam grading separator, allowing PFAS molecules to be further concentrated.

[0044] PFAS molecules can be removed using any of a variety of suitable systems. An example of such a system is shown below. Figure 1A In some embodiments, the system includes a membrane separator comprising at least one semipermeable membrane defining a permeate side and a residual side of the membrane separator. For example, as... Figure 1AAs shown, system 100 includes a membrane separator 110, which includes a semipermeable membrane 125 defining a permeate side 120 and a residual side 115 of the membrane separator 110. In some embodiments, the residual side of the membrane separator is configured to receive a membrane separator residual input comprising PFAS molecules, a liquid, and a surfactant. For example, in Figure 1A In this membrane separator 110, the permeate side 115 is configured to receive a membrane separator permeate input 160 comprising PFAS molecules, a liquid, and a surfactant. The membrane separator permeate input can be received by the membrane separator in any of a variety of ways. For example, as... Figure 1A As shown, PFAS molecules, liquid, and surfactant enter the membrane separator in a single flow. In other embodiments, PFAS molecules, liquid, and surfactant may enter the membrane separator in two or more separate flows. Specific examples of configurations for feeding materials to the membrane separator and other components are described in more detail below.

[0045] In some embodiments, the membrane separator residual input entering the membrane separator on the residual side comprises at least a portion of the feed (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight). For example, such as... Figure 1A As shown, the membrane separator permeate input 160 entering the permeate side 115 of the membrane separator 110 comprises all of the feed 105. In some embodiments, in addition to comprising at least some of the feed, the membrane separator permeate input may also comprise any of a variety of other components, such as part or all of one or more of the outputs of one or more other components of the system (e.g., the foam grading and recovery outputs described elsewhere in this disclosure).

[0046] In some embodiments, the system includes a foam grading separator that has an inlet fluidly connected to the permeate side of a membrane separator and configured to receive foam grading input. For example, as... Figure 1AAs shown, system 100 includes a foam grading separator 130, which includes an inlet 165 fluidly connected to the permeate side 120 of membrane separator 110 and configured to receive foam grading separator input 135. In some embodiments, the concentration of PFAS molecules in the membrane separator permeate input can be greater than (e.g., at least 1.10 times, at least 1.25 times, at least 1.40 times, at least 1.50 times, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 10 times, at least 50 times, at least 100 times, and / or up to 300 times, up to 500 times, up to 1000 times, or more) the concentration of PFAS molecules in the foam grading separator input. For example, as Figure 1A As shown, the concentration of PFAS molecules in the membrane separator residual input 160 is greater than the concentration of PFAS molecules in the foam grading separator input 135. Further details regarding the relative concentrations of the system's inputs and outputs are described in more detail elsewhere in this disclosure for some embodiments.

[0047] As used in this article, when the second quantity is X times larger than the first quantity, then the size of the second quantity is X times the first quantity. For example, if the first quantity is 5 and the second quantity is 100, then the second quantity is 20 times larger than the first quantity (because 5 times 20 is 100). Similarly, as used in this article, when the first quantity is less than the second quantity by a factor of X, then again, the size of the second quantity is X times the first quantity. In the above examples, the first quantity would be said to be less than the second quantity by a factor of 20 (again, because 5 times 20 is 100).

[0048] In some embodiments, the system includes a foam grading separator comprising one or more outlets configured to output a foam-graded product with a PFAS molecule concentration lower than that of the foam grading separator input. For example, as... Figure 1A As shown, system 100 includes a foam grading separator 130, which includes an outlet 170A configured to output a foam grading product output 150 with a PFAS molecule concentration lower than that of the foam grading separator input 135. Specific examples of the configuration for outputting the foam grading product output are described in more detail below. In some embodiments, the concentration of PFAS molecules in the foam grading separator input is greater than the concentration of PFAS molecules in the foam grading product output (e.g., at least 1.10 times, at least 1.25 times, at least 1.40 times, at least 1.50 times, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 10 times, at least 50 times, at least 100 times, and / or up to 500 times, up to 1000 times, or more).

[0049] In some embodiments, the system includes a foam grading separator comprising one or more outlets configured to output foam grading recycled output containing at least some of PFAS molecules and at least some of surfactants. For example, as... Figure 1A As shown, system 100 includes a foam grading separator 130, which includes an outlet 170B configured to output foam grading recovery output 140, which contains at least some of PFAS molecules and at least some of surfactants. In some embodiments, the concentration of PFAS molecules in the foam grading recovery output is greater than the concentration of PFAS molecules in the foam grading separator input (e.g., at least 1.25 times, at least 1.40 times, at least 1.50 times, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 10 times, at least 50 times, at least 100 times, at least 1,000 times, at least 10,000 times, at least 100,000 times, and / or up to 500,000 times, up to 1,000,000 times, or more times). Specific examples of configurations for outputting foam grading recovery output are described in more detail elsewhere in this disclosure.

[0050] In some embodiments, the foam grading separator input entering the foam grading separator comprises at least a portion of the membrane grading separator permeate output exiting the membrane grading separator (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight). For example, such as Figure 1A As shown, the foam grading separator input 135 entering the foam grading separator 130 includes all of the membrane separator permeate output 145 exiting the membrane separator 110.

[0051] In some implementations, the foam grading and recycling output can be recycled and / or treated via membrane separators. An example of such an arrangement is shown in... Figure 1B middle. Figure 1B and Figure 1AEssentially the same, the difference being that the foam grading and recovery output 140 is recycled and treated via membrane separator 110. In some embodiments, the membrane separator permeate input entering the membrane separator contains at least a portion of the foam grading and recovery output exiting the foam grading separator (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight). For example, in Figure 1B In the membrane separator 110, the membrane separator permeate input 160 includes all of the foam classification recovery output 140 that exits the foam classification separator 130.

[0052] In some implementations, the system described herein includes containers. An example of such a system is shown below. Figure 1C middle. Figure 1C and Figure 1A Similar, but also includes a container 175 in fluid communication with the membrane separator 110. In some embodiments, the container is configured to receive at least a portion (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight) via one or more inlets. For example, as Figure 1C As shown, container 175 is configured to receive, via inlet 180, all of the membrane separator residual output 155 exiting from the residual side 115 of membrane separator 110. In some embodiments, the container is configured to receive at least a portion of the feed via one or more inlets (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight). For example, turning again... Figure 1CContainer 175 is configured to receive the entire feed 105 via inlet 185. In some embodiments, the container is configured to discharge 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%, at least 99.9 wt%, or 100 wt%) and / or up to 90 wt%, up to 95 wt%, up to 99 wt%, or up to 100 wt%) to the membrane separator via one or more outlets. For example, as Figure 1C As shown, container 175 is configured to discharge the entire amount of membrane separator residue input 160 to membrane separator 110 via outlet 195. According to some embodiments, the container can be used to provide a stable source of liquids, PFAS molecules, and / or surfactants to other components of the system. Although Figure 1C The image shows a container, but in other embodiments, multiple containers may be used (e.g., one for the liquid and PFAS molecules, and another for the surfactant).

[0053] In some embodiments, the container is configured to receive at least a portion (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight) of the foam grading recyclable output exiting the foam grading separator. An example of such a system is shown in Figure 1D middle. Figure 1D and Figure 1C Essentially the same, except that container 175 is configured to receive the entirety of the foam grading recovery output 140 exiting the foam grading separator 130 via inlet 190. By receiving at least a portion of the foam grading recovery output, the container can provide at least a portion of the foam grading recovery output to the membrane separator for recycling and / or further processing (e.g., to further concentrate PFAS molecules).

[0054] As mentioned above, PFAS molecules can be removed using any of a variety of suitable systems. Another example of such a system is shown in... Figure 2A In some implementations, the system includes foam grading separators. For example, such as... Figure 2A As shown, system 100 includes a foam grading separator 130. In some embodiments, the foam grading separator includes one or more inlets configured to receive foam grading separator inputs. For example, as... Figure 2AAs shown, the foam grading separator 130 includes an inlet 165 configured to receive a foam grading separator input 135. In some embodiments, the foam grading separator input comprises PFAS molecules and a liquid. Further details regarding the foam grading separator input can be found elsewhere in this disclosure.

[0055] In some embodiments, the foam grading separator is configured to receive a foam grading separator input comprising at least a portion of the feed (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight). For example, such as... Figure 2A As shown, the foam grading separator 130 is configured to receive the foam grading separator input 135, which contains the entirety of the feed 105.

[0056] In some implementations, the foam grading separator includes one or more outlets configured to output foam grading and recycling outputs. For example, such as Figure 2A As shown, the foam grading separator 130 includes an outlet 170B configured to output foam grading recovery output 140. In some embodiments, the concentration of PFAS molecules in the foam grading recovery output is greater than the concentration of PFAS molecules in the foam grading product output (e.g., at least 2.5 times, at least 3 times, at least 4 times, at least 5 times, at least 10 times, at least 50 times, at least 100 times, at least 1,000 times, at least 100,000 times, at least 1,000,000 times, and / or up to 500,000,000 times, up to 1,000,000,000 times, or more). Further details regarding the foam grading separator are described elsewhere in this disclosure.

[0057] In some embodiments, the foam grading input can be processed by a foam grading separator such that the concentration of PFAS molecules in the foam grading recovery output is greater than the concentration of PFAS molecules in the foam grading separator input (e.g., at least 1.10 times, at least 1.25 times, at least 1.40 times, at least 1.50 times, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 10 times, at least 50 times, at least 100 times, at least 1,000 times, at least 10,000 times, at least 100,000 times, and / or up to 500,000 times, up to 1,000,000 times, or more). For example, the concentration of PFAS molecules exiting the foam grading recovery output 140 from the membrane separator 110 is greater than the concentration of PFAS molecules in the foam grading separator input 135. In some embodiments, the foam grading separator includes one or more outlets configured to output foam grading product outputs with a PFAS molecule concentration lower than that of the foam grading separator input. For example, such as Figure 2A As shown, the foam grading separator 130 includes an outlet 170A configured to output a foam grading product output 150 with a PFAS molecule concentration lower than that of the foam grading separator input 135. In some embodiments, the concentration of PFAS molecules in the foam grading product output is less than the concentration of PFAS molecules in the foam grading separator input (e.g., by a factor of at least 1.25, at least 1.40, at least 1.50, at least 2, at least 3, at least 4, at least 5, at least 10, at least 100, and / or up to 500, up to 1000, or more).

[0058] In some embodiments, the system includes a membrane separator comprising at least one semipermeable membrane defining a permeate side and a residual side of the membrane separator. For example, such as Figure 2A As shown, system 100 includes a membrane separator 110, which includes at least one semi-permeable membrane 125 defining a permeate side 120 and a residual side 115 of the membrane separator 110. In some embodiments, the residual side of the membrane separator is configured to receive at least a portion of the foam grading recovery output comprising PFAS molecules, liquid, and surfactant. For example, in Figure 2A In this process, the permeate side 115 of the membrane separator 110 is configured to receive the entirety of the foam fractionation recovery output 140, which contains PFAS molecules, liquid, and surfactant.

[0059] In some embodiments, the foam grading and recovery effluent can be recycled and further processed through a membrane separator. In some embodiments, the membrane separator permeate input contains 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%, at least 99.9 wt%, or 100 wt%) of the foam grading and recovery effluent exiting the foam grading separator, and / or up to 90 wt%, up to 95 wt%, up to 99 wt%, or up to 100 wt%). For example, in... Figure 2A In this embodiment, the membrane separator permeate input 160 contains all of the foam grading recovery output 140 exiting the foam grading separator 130. In some embodiments, the concentration of PFAS molecules in the membrane separator permeate output is greater than the concentration of PFAS molecules in the membrane separator permeate input (e.g., at least 1.10 times, at least 1.25 times, at least 1.40 times, at least 1.50 times, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 10 times, at least 100 times, and / or up to 200 times, up to 300 times, up to 500 times, or more). For example, as... Figure 2A As shown, the concentration of PFAS molecules in the membrane separator permeate output 155 can be greater than the concentration of PFAS molecules in the membrane separator permeate input 160 entering the permeate side 115 of the membrane separator 110.

[0060] In some implementations, the membrane separator is configured to output the membrane separator permeate effluent. For example, such as... Figure 2A As shown, membrane separator 110 is configured to output membrane separator permeate effluent 145 from the permeate side 120 of membrane separator 110. In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent is greater than the concentration of PFAS molecules in the membrane separator permeate effluent. For example, the concentration of PFAS molecules in the membrane separator permeate effluent 155 exiting the permeate side 115 of membrane separator 110 is higher than the concentration of PFAS molecules in the membrane separator permeate effluent 145 exiting the permeate side 120 of membrane separator 110.

[0061] In some implementations, the system includes a container configured to receive foam grading recovery output and / or membrane separator residual output. An example of such a system is shown below. Figure 2B In the middle. For example Figure 2BAs shown, system 100 includes container 175. Container 175 is configured to receive foam grading recovery output 140 via inlet 190 and / or receive membrane separator residual output 155 exiting the residual side 115 of membrane separator 110 via inlet 180. In some embodiments, the container serves to provide a stable source of liquid, PFAS molecules, and / or surfactants to the membrane separator.

[0062] In some embodiments, the foam grading separator input contains at least a portion of the membrane separator permeate output (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight). For example, such as... Figure 2B As shown, the foam grading separator input 135 comprises the entirety of the membrane separator permeate output 145 exiting the permeate side 120 of the membrane separator 110. In some embodiments, the foam grading separator input contains a relatively low concentration of PFAS molecules.

[0063] Although Figures 1A to 1D and Figures 2A to 2B This includes both membrane separators and foam grading separators; however, the use of foam grading separators is optional, and in some embodiments, only membrane separators may be used. An example of such an embodiment is shown in… Figure 3 In. Figure 3 In this system 100, a membrane separator 110 includes a semi-permeable membrane 125 that establishes a permeate side 115 and a permeate side 120. The system 100 also includes a membrane separator permeate outlet 145 exiting the permeate side 120 of the membrane separator 110 and a membrane separator permeate inlet 160 entering the permeate side 115 of the membrane separator 110. The membrane separator permeate inlet 160 includes a feed 105 and may optionally include a membrane separator permeate outlet 155.

[0064] PFAS molecules can be removed from the feed using any of a number of suitable methods. (The following will be used...) Figure 3 The system shown is for reference and Figures 1A to 1D and Figures 2A to 2B The system shown is illustrated as an example to describe such a method. In some embodiments, the method includes removing a certain amount of PFAS molecules from a feed containing liquid and PFAS molecules. For example, as Figure 3 As shown, the method may include removing a certain amount of PFAS molecules from a feed 105 containing liquid and PFAS molecules. Similarly, it can be used... Figures 1A to 1Dand Figures 2A to 2B The system shown is used to remove PFAS molecules from feed 105.

[0065] In some embodiments, removal includes conveying a membrane separator permeate input to the permeate side of the membrane separator, the membrane separator permeate input comprising at least a portion of the feed and a surfactant, the presence of which causes at least some of the PFAS molecules to associate with micelles containing the surfactant. For example, as... Figure 3 As shown, removal may include conveying a membrane separator residue input 160 to the residue side 115 of the membrane separator 110, the membrane separator residue input 160 comprising at least a portion of the feed 105 and a surfactant, the presence of which causes at least some of the PFAS molecules to associate with the surfactant-containing micelles. This can be used... Figures 1A to 1D and Figures 2A to 2B The system shown achieves similar operation. In some embodiments, the membrane separator permeate input is conveyed such that the membrane separator permeate output exits from the permeate side of the membrane separator. For example, as... Figure 3 As shown, the membrane separator permeate inlet 160 is conveyed such that the membrane separator permeate outlet 155 exits from the permeate side of the membrane separator. This can be used... Figures 1A to 1D and Figures 2A to 2B The system shown achieves similar operations.

[0066] In some embodiments, the membrane separator permeate input is conveyed such that at least a portion of the liquid from the membrane separator permeate input is transported from the permeate side of the membrane separator through the semipermeable membrane of the membrane separator to the permeate side of the membrane separator, to form part or all of the membrane separator permeate output in which the concentration of PFAS molecules is lower than the concentration of PFAS molecules in the membrane separator permeate input. For example, as Figure 3 As shown, the membrane separator permeate input 160 is conveyed such that at least a portion of the liquid from the membrane separator permeate input 160 is transported from the permeate side 115 of the membrane separator 110 through the semipermeable membrane 125 of the membrane separator 110 to the permeate side 120 of the membrane separator 110, to form part or all of the membrane separator permeate output 145, in which the concentration of PFAS molecules is lower than the concentration of PFAS molecules in the membrane separator permeate input 160. This can be used... Figures 1A to 1D and Figures 2A to 2B The system shown achieves similar operations.

[0067] In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent is greater than the concentration of PFAS molecules in the membrane separator permeate effluent (e.g., at least 1.03 times, at least 1.035 times, at least 1.05 times, at least 1.10 times, at least 1.25 times, at least 1.40 times, at least 1.50 times, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 10 times, and / or up to 20 times, up to 50 times, or more times). In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent is greater than the concentration of PFAS molecules in the membrane separator permeate influent (e.g., at least 1.03 times, at least 1.035 times, at least 1.05 times, at least 1.10 times, at least 1.25 times, at least 1.40 times, at least 1.50 times, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 10 times, and / or up to 20 times, up to 50 times, or more times).

[0068] In some embodiments, the membrane separator residual input includes at least a portion of the membrane separator residual output, which includes at least some of the PFAS molecules delivered to the residual side of the membrane separator. For example, as... Figure 3 As shown, the membrane separator residual input 160 includes at least a portion of the membrane separator residual output 155, which includes at least some of the PFAS molecules delivered to the residual side 115 of the membrane separator 110. Similar operation is shown, for example... Figures 1C to 1D and Figure 2BIn some embodiments, the membrane separator residual input contains at least a portion of the membrane separator residual output (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight). Specific examples of configurations for the membrane separator residual input and other components are described in more detail below. Therefore, since the membrane separator residual input can contain at least a portion of the membrane separator residual output, the membrane separator residual output can advantageously be recycled through the membrane separator, thereby enhancing the separation of PFAS molecules from the residual liquid in the membrane separator residual output. As the membrane separator residual output is recycled back into the membrane separator, the concentration of PFAS molecules in the membrane separator residual output can increase as liquid is removed (e.g., by permeation via a semipermeable membrane). In some implementations, the recycling of membrane separator permeate output in this manner can advantageously reduce the amount of liquid that may need to be discarded during the removal (and / or subsequent destruction) of PFAS molecules.

[0069] In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent is lower than the concentration of PFAS molecules in the feed (e.g., at least 90%, at least 95%, or at least 99%). For example, see reference. Figures 1A to 1D and Figure 3 In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent 145 is at least 90% lower than the concentration of PFAS molecules in the feed 105. As another example, see [reference needed]. Figures 2A to 2B In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent 145 is at least 90% lower than the concentration of PFAS molecules in the feed 105.

[0070] As used in this article, when the first quantity is lower than the second quantity by a certain percentage X%, this means that the first quantity is 100% of the second quantity minus X%. For example, if the first quantity is 90% lower than the second quantity, then the first quantity is 10% of the second quantity (because 100% minus 90% equals 10%). As a concrete example, if the second quantity is 50, and the first quantity is 90% lower than the second quantity, then the first quantity will be 5 (because 10% of 50 is 5).

[0071] Similarly, as used in this article, when the first quantity is higher than the second quantity by a certain percentage Y%, this means that the first quantity is 100% of the second quantity plus Y%. To illustrate, if the first quantity is 90% greater than the second quantity, then the first quantity is 190% of the second quantity. As a concrete example, if the second quantity is 50, and the first quantity is 90% greater than the second quantity, then the first quantity will be 95 (because 100% plus 90% is 190%, and 190% of 50 is 95).

[0072] In some embodiments, the concentration of surfactant in the membrane separator residue input is greater than or equal to 100 mg / L and less than or equal to 1000 mg / L. In some embodiments, the concentration of surfactant in the membrane separator residue input is greater than or equal to 200 mg / L and less than or equal to 360 mg / L. In some embodiments, the membrane separator residue input has a relatively low concentration of surfactant. Further details regarding the concentration of surfactant in the system feed and / or input / output are described elsewhere in this disclosure.

[0073] Various embodiments are described, including inputs (e.g., foam grading separator input, membrane separator permeate input, etc.) and outputs (e.g., foam grading recovery output, membrane separator permeate output, etc.). In each case, the inputs and / or outputs can be in the form of a single stream or multiple streams. In some embodiments, it may be advantageous to use a single stream instead of multiple streams. Thus, in some embodiments, the foam grading separator input is in the form of a single stream. In some embodiments, the foam grading recovery output is in the form of a single stream. In some embodiments, the foam grading product output is in the form of a single stream. In some embodiments, the membrane separator permeate input is in the form of a single stream. In some embodiments, the membrane separator permeate output is in the form of a single stream. In some embodiments, the membrane separator permeate output is in the form of a single stream.

[0074] According to certain embodiments, the systems and methods described in this disclosure relate to the handling of feed. The feed can take any of a variety of forms. For example, the feed can be in a form suitable for input into a fluid device, including but not limited to membrane separators, foam grading separators, containers, and / or components for fluid control. For example, in Figure 1AIn this system, system 100 is configured to receive feed 105, at least a portion of which can be fed into membrane separator 110 via membrane separator permeate input 160, said membrane separator 110 including a semipermeable membrane 125 defining a permeate side 115 and a permeate side 120. Membrane separator permeate input 160, containing at least a portion of feed 105, can enter the permeate side 115 of membrane separator 110, such that part or all of the membrane separator permeate input 160 is conveyed through the semipermeable membrane 125, while PFAS molecules are retained by the semipermeable membrane 125. This can result in an increased concentration of PFAS in the output from the permeate side 115 relative to the input entering the permeate side 115. As another example, in Figure 1C In this system, system 100 is configured to receive feed 105, at least a portion of which can be fed into container 175. In some embodiments, the membrane separator permeate input contains at least a portion of the feed. For example, in Figure 1A In this embodiment, the membrane separator residual input 160 entering the membrane separator 110 on the residual side 115 includes at least a portion of the feed 105. In some embodiments, the container, membrane separator, and / or foam grading separator may receive the feed via an inlet.

[0075] In some embodiments, the feed is a single stream (e.g., a stream containing liquid) comprising all components to be introduced into the fluid device (e.g., introduced into the membrane separator via a membrane separator permeate input). In some embodiments, the feed has multiple streams. In any case, according to certain embodiments, the feed is an input to the system from one or more external sources as described below. Thus, in some embodiments, the feed introduces PFAS molecules into the system for subsequent removal. In some embodiments, either the input and / or output contains a portion of the feed or contents derived from the feed (e.g., PFAS molecules and / or liquid). In some embodiments, the feed introduces both PFAS molecules and liquid into the system. That is, the feed can serve as a source for the system, allowing the system to receive liquid and PFAS molecules for subsequent removal of PFAS molecules.

[0076] In some embodiments, the feed comprises PFAS molecules. The feed can originate from any of a variety of different sources. For example, in some embodiments, the feed is partially or entirely derived from an industrial waste stream containing PFAS molecules (e.g., waste material from industrial processes and / or manufacturing processes) and / or a liquid source exposed to an industrial waste stream containing PFAS molecules. In some embodiments, the feed comprises liquid and / or PFAS molecules. In some embodiments, the feed also contains any of a variety of undesirable contaminants, waste products, and / or compounds that may be present in a variety of applications. In some embodiments, the feed is a stream. In some embodiments, the feed is a single stream comprising liquid and PFAS molecules. That is, the feed may be in the form of a single flow containing liquid and PFAS molecules. In some embodiments, the feed comprises multiple streams, each of which contains at least a portion of liquid and / or PFAS molecules. In some embodiments, the multiple streams are combined within a fluid device or container before being fed into a fluid device (e.g., a membrane separator or foam grading separator). Each of the multiple streams may have a different composition before they are combined. As an example, some of the multiple streams may contain relatively high amounts of PFAS molecules, while others may contain relatively high amounts of liquid. In other embodiments, the multiple streams are introduced into a fluid device (e.g., a membrane separator or a foam grading separator) via separate inlets.

[0077] In some embodiments, the PFAS molecule contains at least one perfluoroalkyl moiety (-C n F 2n+1 In some embodiments, the PFAS molecule comprises a perfluorinated methyl group (-CF3). In some embodiments, the PFAS molecule comprises and / or a perfluorinated methylene group (-CF2-). Examples of perfluoroalkyl moieties include, but are not limited to, perfluorooctane (R-C8F). 17 ), perfluorohexane (R-C6F) 13), and / or perfluorobutane (R-C4F9), wherein "R" can be any of a variety of head groups, including but not limited to carboxylic acids, sulfonic acids, and / or phosphonic acids. In some embodiments, PFAS molecules include perfluorooctanoic acid, perfluorooctane sulfonic acid, perfluorohexane sulfonic acid, perfluorobutane sulfonic acid (PFBS), perfluorobutyric acid, perfluoroalkyl acid (PFAA), perfluoroalkyl carboxylic acid, perfluoroalkyl carboxylate, perfluoroalkyl sulfonic acid, perfluoroalkyl sulfonate (PFSA), perfluoroalkyl ether acid, perfluoroalkyl sulfonyl fluoride (PASF), perfluoroalkyl sulfonamide (FASA), perfluoroalkyl sulfonyl fluoride (PFA), perfluoroalkyl iodide (PFAI), perfluoroalkyl aldehyde, fluoropolymer, polyfluoroalkyl sulfonamide, polyfluoroalkyl ether acid, chlorinated polyfluoroalkyl ether acid, and / or chlorinated polyfluoroalkyl acid. In some implementations, PFAS molecules include one or more molecules disclosed in the “Per- and Polyfluoroalkyl Substances (PFAS) Report” published in March 2023 by the Joint Subcommittee of the Strategy Group on Environment, Innovation and Public Health of the National Science and Technology Commission (which is incorporated herein by reference in its entirety for all purposes).

[0078] In some embodiments, at least some of the PFAS molecules (e.g., at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, at least 90 mol%, at least 95 mol%, at least 99 mol%, or all) are anionic. For example, some of the PFAS molecules may contain carboxyl groups, phosphate groups, and / or sulfonate groups. In some embodiments, when present in the feed, at least some of the PFAS molecules (e.g., at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, at least 90 mol%, at least 95 mol%, at least 99 mol%, or all) are anionic. In some embodiments, at least some of the PFAS molecules (e.g., at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, at least 90 mol%, at least 95 mol%, at least 99 mol%, or all) contain negatively charged end groups. In some embodiments, at least some of the PFAS molecules (e.g., at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, at least 90 mol%, at least 95 mol%, at least 99 mol%, or all) comprise polar moieties (e.g., carboxyl groups, phosphate groups, sulfonate groups). In some embodiments, at least some of the PFAS molecules (e.g., at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, at least 90 mol%, at least 95 mol%, at least 99 mol%, or all) comprise nonpolar moieties (e.g., fluorinated or fully saturated alkyl chains). PFAS molecules can have any of a variety of molecular weights. In some implementations, the molecular weight of the PFAS molecule is at least 100 g / mol, at least 150 g / mol, at least 200 g / mol, at least 250 g / mol, at least 300 g / mol, at least 400 g / mol, at least 500 g / mol, at least 600 g / mol, and / or up to 800 g / mol, up to 1000 g / mol, or higher.In some embodiments, at least some (e.g., at least 10 mol%, at least 25 mol%, at least 50 mol%, at least 75 mol%, at least 90 mol%, at least 95 mol%, at least 99 mol%, or all) of the PFAS molecule comprise an alkyl chain containing at least 2 carbon atoms, at least 4 carbon atoms, at least 6 carbon atoms, at least 8 carbon atoms, at least 10 carbon atoms, at least 12 carbon atoms, at least 14 carbon atoms, at least 16 carbon atoms, at least 18 carbon atoms, at least 20 carbon atoms, and / or up to 25 carbon atoms, up to 30 carbon atoms, or more.

[0079] In some embodiments, the feed contains a relatively high concentration of dissolved ions. The dissolved ions may not be PFAS molecules and may not be surfactants. Examples of such dissolved ions include, but are not limited to, sulfate, calcium, sodium, and / or chloride. In some embodiments, the atomic weight or molecular weight of the dissolved ions is less than or equal to 100 g / mol or less. The dissolved ions may include cations and anions of a dissolved salt. For example, the feed may contain calcium sulfate (CaSO4), which dissociates in water to form calcium and sulfate ions. Other dissolved ions are also possible, including oxoanions, halide ions, and / or ions containing Group I and / or Group II elements.

[0080] In some embodiments, the membrane separator is capable of retaining a relatively high percentage of PFAS molecules (e.g., as part of PFAS-associated micelles) while allowing a relatively large percentage of dissolved ions (e.g., sulfate ions) to be transported from the permeate side of the membrane separator through the semipermeable membrane to the permeate side. The dissolved ions can then exit the membrane separator via the permeate effluent. For example, as... Figure 1A As shown, a membrane separator effluent input 160 containing dissolved ions and PFAS molecules enters the effluent side 115 of the membrane separator 110. While some or all of the PFAS molecules and / or PFAS-associated micelles may be trapped and exit the membrane separator 110 via the membrane separator effluent output 155, some or all of the dissolved ions can be transported from the effluent side 115 of the membrane separator 110 through the semipermeable membrane 125 to the permeate side 120 of the membrane separator 110. The dissolved ions can exit the membrane separator 110 via the membrane separator permeate output 145.

[0081] In some implementations, the semipermeable membrane has a relatively low percentage rejection of dissolved ions (e.g., non-PFAS and non-surfactant ions) compared to the rejection rates of other molecules such as PFAS molecules. During the liquid separation process, the percentage rejection R of the semipermeable membrane for the solute can be determined by C. R(The concentration of solute in the permeate input of the membrane separator on the permeate side) and C P (The concentration of solute in the permeate output of the membrane septum on the permeate side) is calculated and expressed as a percentage using the following equation [1]:

[0082]

[0083] In some embodiments, the semipermeable membrane of the membrane separator is configured to retain (e.g., under the conditions of the methods of this disclosure) dissolved ions at a retention rate percentage of less than or equal to 80%, less than or equal to 60%, less than or equal to 50%, less than or equal to 40%, and / or at least 0.5%, at least 0.1%, at least 0.01%, or less. Combinations of these ranges are possible (e.g., less than or equal to 80% and at least 0.01%, or less than or equal to 40% and at least 0.01%). In some embodiments, the semipermeable membrane is configured to retain (e.g., under the conditions of the methods of this disclosure) PFAS molecules and / or PFAS-associated micelles at a retention rate percentage of at least 80%, at least 85%, at least 90%, at least 95%, and / or up to 99%, up to 99.5%, up to 99.9%, or higher (e.g., 100%). Combinations of these ranges are possible. In some embodiments, the ratio of the percentage of PFAS molecules and / or PFAS-associated micelles of the membrane separator to the percentage of dissolved ions (e.g., sulfate) is greater than 1, at least 1.05, at least 1.1, at least 1.2, at least 1.25, at least 1.5, at least 2, at least 3, at least 4, and / or up to 10, up to 100, up to 500, or up to 1000, or higher. Combinations of these ranges are possible (e.g., greater than 1 and up to 1000). Other ranges are also possible.

[0084] In some embodiments, the semipermeable membrane is configured (e.g., under the conditions of the methods of this disclosure) to retain a relatively large percentage of PFAS molecules and / or PFAS-associated micelles, while allowing a relatively high percentage of dissolved ions (e.g., sulfate) to pass through the semipermeable membrane. In some embodiments, it is not desirable to use a semipermeable membrane that retains a relatively high percentage of certain ions (e.g., sulfate) because those ions may foul the semipermeable membrane, thereby degrading its performance. Furthermore, such ionic fouling may affect the performance of downstream processes such as oxidation processes (e.g., for PFAS destruction). In some embodiments, the concentration of dissolved ions in the membrane separator permeate effluent is less than the concentration of dissolved ions in the membrane separator residual effluent (e.g., by a factor of at least 1.005, at least 1.01, at least 1.05, at least 1.1, at least 1.25, at least 1.40, at least 1.50, at least 2, at least 3, at least 4, at least 5, at least 10, at least 100, and / or up to 500, up to 1000, or more). In some embodiments, the concentration of dissolved ions in the membrane separator permeate effluent is within 5%, 2%, 1%, 0.5%, 0.2%, 0.1%, or less of the concentration of dissolved ions in the membrane separator residual effluent. In some embodiments, the concentration of dissolved ions in the membrane separator permeate effluent is the same as the concentration of dissolved ions in the membrane separator residual effluent. In some embodiments, the concentration of dissolved sulfate in the membrane separator permeate effluent is less than the concentration of dissolved sulfate in the membrane separator residual effluent (e.g., by a factor of at least 1.005, at least 1.01, at least 1.05, at least 1.1, at least 1.25, at least 1.40, at least 1.50, at least 2, at least 3, at least 4, at least 5, at least 10, at least 100, and / or up to 500, up to 1000, or more). In some embodiments, the concentration of dissolved sulfate in the membrane separator permeate effluent is within 5%, 2%, 1%, 0.5%, 0.2%, 0.1%, or less of the concentration of dissolved sulfate in the membrane separator residual effluent. In some embodiments, the concentration of dissolved sulfate in the membrane separator permeate effluent is the same as the concentration of dissolved sulfate in the membrane separator residual effluent.

[0085] In some embodiments, the concentration of dissolved ions in the membrane separator permeate input is greater than or equal to 15 mg / L, greater than or equal to 20 mg / L, greater than or equal to 25 mg / L, greater than or equal to 50 mg / L, greater than or equal to 100 mg / L, greater than or equal to 150 mg / L, greater than or equal to 200 mg / L, greater than or equal to 300 mg / L, greater than or equal to 400 mg / L, greater than or equal to 500 mg / L, greater than or equal to 650 mg / L, greater than or equal to 675 mg / L, and / or up to 700 mg / L, or greater. In some embodiments, the concentration of dissolved ions in the permeate effluent from the membrane separator is less than or equal to 700 mg / L, less than or equal to 650 mg / L, less than or equal to 600 mg / L, less than or equal to 500 mg / L, less than or equal to 400 mg / L, less than or equal to 250 mg / L, less than or equal to 100 mg / L, less than or equal to 50 mg / L, less than or equal to 20 mg / L, less than or equal to 10 mg / L, less than or equal to 5 mg / L, less than or equal to 1 mg / L, or less.

[0086] The pH of the membrane separator residue input and / or foam grading separator input can have any of a number of values, depending on the content and / or amount of its components (e.g., PFAS molecules, surfactants). The pH can be a pH that promotes the formation of micelles associated with at least some of the PFAS molecules. In some embodiments, the pH of the membrane separator residue input and / or foam grading separator input is low enough to prevent micelle dissociation. In some embodiments, the pH of the membrane separator residue input and / or foam grading separator input is less than or equal to 9 to prevent micelle dissociation. In some embodiments, the pH of the membrane separator residue input and / or foam grading separator input is greater than or equal to 6.5, greater than or equal to 6.75, greater than or equal to 7, greater than or equal to 7.25, greater than or equal to 7.5, greater than or equal to 7.75, greater than or equal to 8, greater than or equal to 8.25, greater than or equal to 8.5, greater than or equal to 8.75, or greater than or equal to 9. In some embodiments, the pH of the membrane separator residual input and / or the foam grading separator input is less than or equal to 9, less than or equal to 8.75, less than or equal to 8.5, less than or equal to 8, less than or equal to 7.75, less than or equal to 7.5, less than or equal to 7.25, less than or equal to 7, less than or equal to 6.75, or less than or equal to 6.5. Combinations of these ranges are possible (e.g., greater than or equal to 6.5 and less than or equal to 9). Other ranges are possible.

[0087] In some embodiments, the membrane separator residue input and / or foam grading separator input can have any of a variety of volume average temperatures. According to some embodiments, the volume average temperature of the membrane separator residue input and / or foam grading separator input can be approximately ambient temperature. According to some embodiments, membrane separator residue input and / or foam grading separator input with a volume average temperature of approximately ambient temperature (e.g., greater than or equal to 20 degrees Celsius and less than or equal to 25 degrees Celsius) can advantageously allow for relatively large micelle sizes and relatively stable micelle formation. In some embodiments, the volume average temperature of the membrane separator residue input and / or foam grading separator input is greater than or equal to 20 degrees Celsius and less than or equal to 25 degrees Celsius. In some embodiments, the volume average temperature of the feed is greater than or equal to 15 degrees Celsius, greater than or equal to 17.5 degrees Celsius, greater than or equal to 20 degrees Celsius, greater than or equal to 22.5 degrees Celsius, greater than or equal to 25 degrees Celsius, greater than or equal to 27.5 degrees Celsius, or greater than or equal to 30 degrees Celsius. In some embodiments, the volume average temperature of the membrane separator residue input and / or the foam grading separator input is less than or equal to 30 degrees Celsius, less than or equal to 27.5 degrees Celsius, less than or equal to 25 degrees Celsius, less than or equal to 22.5 degrees Celsius, less than or equal to 20 degrees Celsius, less than or equal to 17.5 degrees Celsius, or less than or equal to 15 degrees Celsius. Combinations of these ranges are possible (e.g., greater than or equal to 15 degrees Celsius and less than or equal to 30 degrees Celsius). Other ranges are possible.

[0088] In some embodiments, the membrane separator permeate input and / or foam grading separator input are pressurized. The membrane separator permeate input and / or foam grading separator input can be pressurized by any of a variety of suitable mechanisms, including but not limited to feed pumps and / or gravity. In some embodiments, the membrane separator permeate input and / or foam grading separator input are pressurized to a gauge pressure greater than or equal to 1 bar, greater than or equal to 5 bar, greater than or equal to 10 bar, greater than or equal to 15 bar, or greater than or equal to 20 bar. In some embodiments, the membrane separator permeate input and / or foam grading separator input are pressurized to a gauge pressure less than or equal to 20 bar, less than or equal to 15 bar, less than or equal to 10 bar, less than or equal to 5 bar, or less than or equal to 1 bar. Combinations of these ranges are possible (e.g., greater than or equal to 1 bar and less than or equal to 20 bar). Other ranges are possible.

[0089] In some embodiments, the membrane separator permeate input is pressurized to achieve a desired flux across the semipermeable membrane. In some embodiments, the membrane separator permeate input is pressurized such that the flux across the semipermeable membrane is greater than or equal to 10 liters / m³. 2 / hour (LMH), greater than or equal to 15 LMH, greater than or equal to 20 LMH, greater than or equal to 25 LMH, greater than or equal to 30 LMH, greater than or equal to 35 LMH, or greater than or equal to 40 LMH. In some embodiments, the membrane separator permeate feed is pressurized such that the flux across the semipermeable membrane is less than or equal to 40 LMH, less than or equal to 35 LMH, less than or equal to 30 LMH, less than or equal to 25 LMH, less than or equal to 20 LMH, less than or equal to 15 LMH, or less than or equal to 10 LMH. Combinations of these ranges are possible (e.g., greater than or equal to 10 LMH and less than or equal to 40 LMH). Other ranges are possible.

[0090] In some embodiments, the feed comprises a liquid. In some cases, the liquid comprises industrial waste products. In some embodiments, the liquid comprises water. According to some embodiments, the relatively low reactivity of PFAS molecules makes their removal from liquids (e.g., water) challenging and is generally undesirable in many applications (e.g., in drinking water). Therefore, removing PFAS molecules from the feed can advantageously allow the liquid and / or other components in the feed to be used in a variety of applications and / or introduced into the environment.

[0091] The inputs described throughout this disclosure may contain surfactants. In some embodiments, the surfactant is amphiphilic. In some embodiments, the surfactant may associate with PFAS molecules to form micelles. According to some embodiments, the surfactant allows the formation of micelles associated with PFAS molecules. According to some embodiments, the surfactant can help remove PFAS molecules from the membrane separator residue input because micelles may have limited permeability through a semipermeable membrane.

[0092] In some embodiments, the surfactant may be metered into any of the inputs and / or outputs of the container, separator, or system. In some embodiments, the surfactant is metered in a continuous manner. That is, in some embodiments, the continuous supply of surfactant is introduced with limited interruptions. In some embodiments, the surfactant is metered in intermittently. That is, in some embodiments, the supply of surfactant is introduced in batches (e.g., discrete intermittent doses). In some embodiments, the surfactant is introduced into any of the inputs and / or outputs of the system described herein, including but not limited to foam grading separator inputs, foam grading recovery outputs, membrane separator permeate outputs, membrane separator permeate outputs, and / or membrane separator permeate inputs.

[0093] In some embodiments, the surfactant includes a cationic surfactant. That is, in some embodiments, the surfactant comprises a portion having a net positive charge. In some embodiments, the cationic surfactant can interact with PFAS molecules such that the portion having a net positive charge interacts with a portion of the PFAS molecule having a net negative charge to form micelles. The electrostatic interaction between the portion of the PFAS having a net negative charge and the portion of the cationic surfactant having a net positive charge can allow the formation of relatively stable and relatively large micelles, which facilitates removal using a semipermeable membrane. Advantageously, the electrostatic interaction between the cationic surfactant and the PFAS molecules can allow the removal of relatively short-chain PFAS molecules (e.g., perfluorobutyric acid, perfluorobutane sulfonic acid). Therefore, the electrostatic interaction between the cationic surfactant and the PFAS molecules can facilitate the separation of short-chain PFAS compounds.

[0094] The cationic surfactants described herein may comprise any of a variety of compounds. In some embodiments, the cationic surfactant comprises hexadecyltrimethylammonium bromide (CTAB), trimethyloctylammonium bromide, trimethyloctadecylammonium bromide, dimethyldecylammonium bromide, dimethyldidodecylammonium bromide, dimethylditetradecylammonium bromide, dimethyldihexadecylammonium bromide, dimethyldioctadecylammonium bromide, hexadecyltrimethylammonium chloride, and / or hexadecylpyridine chloride. In some embodiments, the cationic surfactant comprises hexadecyltrimethylammonium bromide (CTAB). In some embodiments, the cationic surfactant comprises a hydrophobic moiety. In some embodiments, the hydrophobic moiety comprises an alkyl group having at least 2, 5, 10, 12, 14, 16, 18, 20, 22, 24, or 25 carbon atoms. In some embodiments, the cationic surfactant comprises a hydrophilic group, said hydrophilic group comprising any of a variety of salts. In some embodiments, the hydrophilic group comprises a quaternary ammonium salt. That is, the hydrophilic group comprises the general formula [NR4]. + A positively charged ion (where R is an alkyl, aryl, or organic group) that can interact with halogen ions (e.g., fluorine, chlorine, bromine, iodine).

[0095] In some embodiments, the surfactant includes anionic and / or nonionic surfactants. In some embodiments, the anionic surfactant comprises a portion having a net negative charge. In some embodiments, the nonionic surfactant may not have a net charge. In some embodiments, the anionic and / or nonionic surfactant can allow the removal of long-chain PFAS molecules and / or other contaminants and can be relatively less expensive than surfactants for removing short-chain PFAS molecules. Therefore, in some embodiments, it can be advantageous to introduce anionic and / or nonionic surfactants into feeds, containers, separators, or any input or output of the system to remove long-chain PFAS molecules, such that a cationic surfactant (which may be relatively expensive) can then be introduced to target short-chain PFAS molecules, thereby limiting the consumption of cationic surfactants by long-chain PFAS molecules. An example of such operation is shown, for example... Figure 12 In some embodiments, anionic and / or nonionic surfactants may be introduced as auxiliary surfactants or as alternatives to cationic surfactants. In some embodiments, anionic and / or nonionic surfactants may be introduced into containers, separators, or any of the various inputs and / or outputs described herein.

[0096] In some embodiments, the surfactant comprises one type of surfactant. In other embodiments, the surfactant comprises more than one type of surfactant. In some embodiments, the surfactant comprises a mixture of surfactants including cationic surfactants, anionic surfactants, and / or nonionic surfactants.

[0097] In some embodiments, the length of the largest alkyl group in the surfactant is similar to that of the largest alkyl group in the PFAS molecule. In some embodiments, the number of carbon atoms in the largest alkyl group in the cationic surfactant is within 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 (or the same) of the number of carbon atoms in the largest alkyl group in the PFAS molecule.

[0098] Surfactants may be present in the membrane separator residue input and / or foam grading separator input at any of a variety of concentrations. In some embodiments, the feed contains surfactant at a relatively low concentration. Using a relatively low concentration may be particularly advantageous because it reduces the capital expenditure required to facilitate the removal of PFAS molecules and reduces the resources required to remove surfactant from the liquid prior to its intended use. In some embodiments, the membrane separator residue input and / or foam grading separator input contains surfactant in amounts greater than or equal to 100 mg / L, greater than or equal to 150 mg / L, greater than or equal to 200 mg / L, greater than or equal to 300 mg / L, greater than or equal to 360 mg / L, greater than or equal to 500 mg / L, greater than or equal to 750 mg / L, or greater than or equal to 1000 mg / L. In some embodiments, the membrane separator residue input and / or foam grading separator input contain surfactant in amounts less than or equal to 1000 mg / L, less than or equal to 750 mg / L, less than or equal to 500 mg / L, less than or equal to 360 mg / L, less than or equal to 300 mg / L, less than or equal to 200 mg / L, less than or equal to 150 mg / L, or less than or equal to 100 mg / L. Combinations of these ranges are possible (e.g., greater than or equal to 100 mg / L and less than or equal to 1000 mg / L, greater than or equal to 200 mg / L and less than or equal to 360 mg / L). Other ranges are also possible.

[0099] In some embodiments, the membrane separator residue input and / or foam grading separator input contain a surfactant in an amount greater than or equal to the critical micelle concentration (CMC). That is, in some embodiments, the surfactant is present in the membrane separator residue input and / or foam grading separator input in an amount sufficient to cause at least some of the PFAS molecules to associate with the surfactant-containing micelles. The CMC can vary based on a variety of parameters, including but not limited to temperature, the valence of the surfactant's counterion, the size of the surfactant's alkyl group, and / or the presence of electrolytes in the membrane separator residue input and / or foam grading separator input. Therefore, in some embodiments, these parameters can be varied such that the concentration of the surfactant in the membrane separator residue input and / or foam grading separator input is greater than or equal to the CMC. In some embodiments, the membrane separator permeate input and / or foam grading separator input contain surfactants in amounts less than or equal to 5 times CMC, less than or equal to 4 times CMC, less than or equal to 3 times CMC, less than or equal to 2 times CMC, less than or equal to 1.5 times CMC, and / or as low as 1.1 times CMC, as low as 1.05 times CMC, or less.

[0100] In some embodiments, the system includes a total organic carbon (TOC) analyzer. In some embodiments, the TOC analyzer allows measurement of the amount of surfactant in any input or output of the system. The TOC analyzer may be electrically connected to a dosing pump responsible for introducing surfactants into any input or output of the system. Therefore, the concentration of surfactants in any input or output or container of the system can be increased, decreased, and / or maintained based on the electrical output of the TOC analyzer.

[0101] As mentioned elsewhere in this disclosure, the presence of a surfactant can allow at least some of the PFAS molecules to associate with the micelles. As used herein, when a PFAS molecule “associates” with a micelle, the PFAS molecule is either part of the micelle or otherwise associates with the micelle such that the PFAS molecule and the micelle move together in the system. For example, the PFAS molecule may attach to the outer portion of the micelle, allowing the PFAS molecule to move with the micelle. As another example, the PFAS molecule may be located within the inner portion of the micelle, allowing the PFAS molecule to move with the micelle. In some embodiments, the micelle contains a surfactant. In some embodiments, the PFAS molecules and the surfactant may interact (e.g., electrostatically), causing the PFAS molecules and the surfactant to align into a micellar structure.

[0102] In some embodiments, the surfactant can allow the formation of micelles associated with PFAS molecules. In some embodiments, micelles containing the surfactant and associated with PFAS molecules can advantageously be removed from a liquid via a fluid device (e.g., a membrane separator comprising a semipermeable membrane). Thus, when PFAS molecules associate with micelles, removal of PFAS molecules from the liquid can be facilitated. In some embodiments, the micelles contain a surfactant. Some of the PFAS molecules can electrostatically interact with the surfactant. For example, the anionic portion of the PFAS molecule can electrostatically interact with the cationic portion of the surfactant, thereby allowing the formation of relatively stable micelles containing both the surfactant and PFAS. The relative stability of the micelles can be advantageous for the removal of at least some of the PFAS molecules from the liquid because the micelles can resist removal from the liquid via membrane separators and / or foam staging separators. Furthermore, the electrostatic interaction between the surfactant and some of the PFAS molecules can allow the formation of relatively large micelles, which can further facilitate the removal of PFAS molecules from the liquid.

[0103] In some embodiments, at least some of the micelles have relatively large molecular weights, which can advantageously facilitate the removal of PFAS molecules from the liquid. In some embodiments, at least some of the micelles (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight) have molecular weights greater than or equal to 100 Daltons (Da), greater than or equal to 500 Da, greater than or equal to 750 Da, greater than or equal to 1000 Da, greater than or equal to 1500 Da, greater than or equal to 2000 Da, greater than or equal to 2500 Da, or greater than or equal to 3000 Da. In some embodiments, at least some of the micelles (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight) have molecular weights less than or equal to 3000 Da, less than or equal to 2500 Da, less than or equal to 2000 Da, less than or equal to 1500 Da, less than or equal to 1000 Da, less than or equal to 750 Da, less than or equal to 500 Da, or less than or equal to 100 Da. Combinations of these ranges are possible (e.g., greater than or equal to 100 Da and less than or equal to 3000 Da). Other ranges are also possible.

[0104] As described above, some embodiments include conveying a permeate input to the permeate side of the membrane separator. A membrane separator refers to an assembly comprising one or more semi-permeable membranes configured to perform a membrane-based separation process (e.g., permeation, filtration, or a combination thereof) on at least one input and produce at least one output. A membrane separator may include at least one semi-permeable membrane defining a permeate side and a permeate side of the membrane separator. Each membrane separator described herein may include additional subunits, such as a single semi-permeable membrane module (e.g., in the form of a cartridge), valves, fluid conduits, etc. As described in more detail below, each membrane separator may include a single semi-permeable membrane or multiple semi-permeable membranes. In some embodiments, a single membrane separator may include multiple subunits (e.g., multiple modules, such as multiple cartridges) that may or may not share a common container. In some embodiments, the system includes two or more membrane separators fluidly connected to each other.

[0105] In some embodiments, the membrane separator permeate input is delivered to the permeate side of the membrane separator, such that the membrane separator permeate output leaves the permeate side of the membrane separator, and the concentration of PFAS molecules in the membrane separator permeate output is greater than the concentration of PFAS molecules in the membrane separator permeate input (e.g., at least 1.03 times, at least 1.035 times, at least 1.05 times, at least 1.10 times, at least 1.25 times, at least 1.40 times, at least 1.50 times, at least 2 times, at least 3 times, at least 4 times, at least 5 times, at least 10 times, and / or up to 20 times, up to 50 times, or more times).

[0106] Figure 4AThis is a schematic diagram of a membrane separator 400A, in which a single semipermeable membrane is used to separate the permeate side 120 from the residue side 115. Membrane separator 400A can be operated by conveying a membrane separator residue input 160 through the residue side 115. At least a portion (e.g., at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 50 wt%, and / or up to 60 wt%, up to 70 wt%, up to 80 wt%, and / or up to 90 wt%, or more) of the liquid (e.g., solvent) within the membrane separator residue input 160 can be conveyed through the semipermeable membrane 125 to the permeate side 120. This can result in the formation of a membrane separator residue output 155, which may contain a higher concentration of solute (e.g., PFAS molecules) than the solute concentration contained in the membrane separator residue input 160 and the membrane separator permeate output 145. In some embodiments, the membrane separator permeate output 145 may correspond to the liquid (e.g., solvent) delivered from the permeate side 115 to the permeate side 120 of the membrane separator residual input 160. The membrane separator permeate output 145 may also contain some solute (e.g., PFAS molecules), but because the solute is selectively excluded to prevent it from being delivered through the semipermeable membrane 125, the membrane separator permeate output 145 will typically contain much less solute.

[0107] In some embodiments, the membrane separator comprises a plurality of semipermeable membranes. In some such embodiments, the plurality of semipermeable membranes within the membrane separator are connected in series. In some such embodiments, the plurality of semipermeable membranes within the membrane separator are connected in parallel. In some embodiments, the membrane separator comprises a plurality of membranes, a first portion of which is connected in series, and another portion of which is connected in parallel.

[0108] In some implementations, the membrane separator comprises a plurality of semipermeable membranes connected in parallel. An example of such an arrangement is shown in... Figure 4B In. Figure 4BIn this membrane separator 400B, three semipermeable membranes 125A, 125B, and 125C are arranged in parallel. The membrane separator permeate input 160 is divided into three sub-inputs (160A, 160B, and 160C), one sub-input being fed to the permeate side 115A of semipermeable membrane 125A, another sub-input to the permeate side 115B of semipermeable membrane 125B, and yet another sub-input to the permeate side 115C of semipermeable membrane 125C. The membrane separator 400B can operate by conveying the membrane separator permeate input sub-inputs through the permeate side of the semipermeable membranes. At least a portion of the liquid (e.g., solvent) within the membrane separator permeate input 160 can be delivered, respectively, through each of the semipermeable membranes 125A, 125B, and 125C to the permeate sides 120A, 120B, and 120C. This can result in the formation of three permeate output sub-outputs (155A, 155B, and 155C), which can be combined to form membrane separator permeate output 155. Membrane separator permeate output 155 can contain a higher concentration of solute (e.g., PFAS molecules) than the solute concentration contained in the membrane separator permeate input 160. Membrane separator permeate output 145 (formed from the three permeate output sub-outputs 145A, 145B, and 145C) can also be formed. The membrane separator permeate output 145 may correspond to the liquid (e.g., solvent) delivered from the permeate side 115A to 115C to the permeate side 120A to 120C of the membrane separator residual input 160. The membrane separator permeate output 145 may also contain some solute (e.g., PFAS molecules), but because the solute is selectively excluded to prevent its transport through the semipermeable membrane 125, the membrane separator permeate output 145 will typically contain much less solute. In some embodiments, as mentioned elsewhere in this disclosure, part or all of the membrane separator residual output may be incorporated into the membrane separator residual input and / or diverted (e.g., rejected) for subsequent destruction (see [link to documentation]). Figures 5 to 6 ).

[0109] Although Figure 4B Three semipermeable membranes connected in parallel are shown, but other embodiments may include two, four, five or more semipermeable membranes connected in parallel. In some embodiments, the semipermeable membranes are fluidly connected to each other.

[0110] In some implementations, the membrane separator comprises a plurality of semipermeable membranes connected in series. An example of such an arrangement is shown in... Figure 4C In. Figure 4C In the membrane separator 400C, three semi-permeable membranes 125A, 125B, and 125C are arranged in series. Figure 4CIn this process, the membrane separator permeate input 160 is first conveyed to the permeate side 115A of the semipermeable membrane 125A. At least a portion of the liquid (e.g., solvent) within the membrane separator permeate input 160A can be conveyed through the semipermeable membrane 125A to the permeate side 120A of the semipermeable membrane 125A. This can result in the formation of the membrane separator permeate output 145A and a first intermediate permeate output 605 conveyed to the permeate side 115B of the semipermeable membrane 125B. At least a portion of the liquid (e.g., solvent) within the first intermediate permeate output 605 can be conveyed through the semipermeable membrane 125B to the permeate side 120B of the semipermeable membrane 125B. This can result in the formation of the membrane separator permeate output 145B and a second intermediate permeate output 610 conveyed to the permeate side 115C of the semipermeable membrane 125C. At least a portion of the liquid (e.g., solvent) within the second intermediate permeate output 610 can be conveyed through the semipermeable membrane 125C to the permeate side 115C of the semipermeable membrane 125C. This can result in the formation of permeate output 145C and membrane separator permeate output 155. According to certain embodiments, Figures 10 to 11 Other examples of semipermeable membranes connected in series are shown.

[0111] Although Figure 4C Three semipermeable membranes connected in series are shown, but other embodiments may include two, four, five or more semipermeable membranes connected in series. In some embodiments, the semipermeable membranes are fluidly connected to each other.

[0112] For a membrane separator comprising multiple semipermeable membranes, parameters such as relative concentrations of the input and output flows of the membrane separator are calculated by mass balancing the entire membrane separator.

[0113] As mentioned above, the membrane separators of the system may include at least one semi-permeable membrane. Typically, 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 permeability of another component). For example, a semi-permeable membrane may block some molecules (e.g., PFAS and associated micelles) from passing through while allowing others (e.g., solvent molecules) to pass through. In some cases, a semi-permeable membrane blocks some molecules and allows others to pass through based on the molecular weight and / or charge of the molecules.

[0114] As described above, semipermeable membranes can be used in osmosis processes. For example, a semipermeable membrane can be a permeation membrane. A permeation membrane can generate an osmotic pressure difference between the solutions on each side of the membrane when a hydraulic pressure difference is applied across the membrane. For example, if a permeation membrane is placed between two solutions of the same composition such that there is initially no osmotic pressure difference across the membrane, applying a hydraulic pressure difference across the permeation membrane can allow components to be transported from one side of the membrane to the other, thereby establishing an osmotic pressure difference across the membrane. Semipermeable membranes can also be used in nanofiltration processes. Semipermeable membranes can be configured for osmosis processes, nanofiltration processes, and / or processes in which separation is achieved based on a combination of nanofiltration and osmosis mechanisms (e.g., based on, for example, the molecular weight cutoff of the membrane, the pore size of the membrane, the nature of the mixture to which they are exposed, and the magnitude of the applied hydraulic pressure).

[0115] Semipermeable membrane media can include, for example, metals, ceramics, polymers (e.g., polyamides, polyethylene, polyesters, poly(tetrafluoroethylene), polysulfones, polycarbonates, polypropylenes, poly(acrylates)) and / or composites or other combinations thereof. Semipermeable membranes typically allow solvents (e.g., water) to selectively pass through the membrane while inhibiting the transport of solutes (e.g., PFAS and associated micelles) through the membrane. Examples of commercially available semipermeable membranes that can be used in association with certain embodiments described herein include, but are not limited to, those commercially available from Dow Water and Process Solutions (e.g., FilmTec). TM Semipermeable membranes from companies such as Hydranautics, GEOsmonics, Suez, LG, Toyobo, Microdyn, and Toray Membrane.

[0116] In some embodiments, the semi-permeable membrane is an ultrafiltration membrane. That is, the molecular weight cutoff of the semi-permeable membrane can be greater than or equal to 200 Da and less than or equal to 5000 Da. In some embodiments, ultrafiltration membranes can advantageously allow the removal of micelles (e.g., PFAS and associated micelles) while generally limiting the amount of PFAS molecules, surfactants, and / or micelles that permeate through the semi-permeable membrane. In some cases, other types of membranes (e.g., ultrafiltration membranes) may be substantially unable to prevent the transport of PFAS molecules from the permeate side of the membrane separator to the permeate side of the membrane separator.

[0117] In some embodiments, the semipermeable membrane has a molecular weight cutoff (MWCO). In some embodiments, the MWCO of the semipermeable membrane is greater than or equal to 200 Da, greater than or equal to 500 Da, greater than or equal to 1000 Da, greater than or equal to 1500 Da, greater than or equal to 2000 Da, greater than or equal to 2500 Da, greater than or equal to 3000 Da, greater than or equal to 3500 Da, greater than or equal to 4000 Da, greater than or equal to 4500 Da, or greater than or equal to 5000 Da. In some embodiments, the MWCO of the semipermeable membrane is less than or equal to 5000 Da, less than or equal to 4500 Da, less than or equal to 4000 Da, less than or equal to 3500 Da, less than or equal to 3000 Da, less than or equal to 2500 Da, less than or equal to 2000 Da, less than or equal to 1500 Da, less than or equal to 1000 Da, less than or equal to 500 Da, or less than or equal to 200 Da. Combinations of these ranges are possible (e.g., greater than or equal to 200 Da and less than or equal to 5000 Da). Other ranges are also possible.

[0118] In some embodiments, the semipermeable membrane comprises an electrically neutral membrane. In some embodiments, the electrically neutral membrane comprises a zwitterion membrane. That is, the semipermeable membrane may contain zwitterions that facilitate the transport of some or all of the permeate input from the permeate side of the membrane separator to the permeate side of the membrane separator, while restricting the transport of organic components (e.g., organic compounds or amphiphilic compounds). In some embodiments, the zwitterion membrane comprises a zwitterionic polymer. In some embodiments, the zwitterionic polymer is disposed on and / or grafted or adsorbed onto the semipermeable membrane. In some embodiments, the zwitterionic polymer associates with the semipermeable membrane via covalent and / or non-covalent interactions (e.g., van der Waals forces). An example of a zwitterion membrane includes those manufactured by ZwitterCo.

[0119] Semipermeable membranes can include any of a variety of suitable properties. In some embodiments, the semipermeable membrane includes one or more hydrophilic surfaces. According to some embodiments, one or more hydrophilic surfaces can facilitate the transport of liquid from the permeate side of the membrane separator through the semipermeable membrane to the permeate side of the membrane separator. In some embodiments, the semipermeable membrane includes antifouling properties. In some cases, the semipermeable membrane may accumulate fouling during use, thereby reducing or occasionally preventing the transport of liquid from the permeate side of the membrane separator to the permeate side of the membrane separator. Therefore, in some embodiments, the semipermeable membrane has antifouling properties (e.g., an antifouling coating), which can advantageously allow relatively high fluxes associated with the liquid transported through the semipermeable membrane. In some embodiments, the semipermeable membrane allows liquid to be transported from the permeate side of the membrane separator to the permeate side of the membrane separator despite relatively high concentrations of surfactants in the liquid. That is, the semipermeable membrane can be able to continuously transport liquid such that the semipermeable membrane does not become completely clogged and / or accumulate fouling. In some embodiments, the semipermeable membrane has a relatively narrow pore size distribution. In some embodiments, the semipermeable membrane includes pores such that the volume of each pore is within at least 1%, at least 5%, at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, or at least 50% of each other. The pore size distribution of the semipermeable membrane can be measured by gel permeation chromatography (GPC).

[0120] In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent is lower than the concentration of PFAS molecules in the membrane separator residual effluent. In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent is at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 97.5%, and / or at least 99% lower than the concentration of PFAS molecules in the membrane separator residual effluent.

[0121] In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent is lower than the concentration of PFAS molecules in the membrane separator residual effluent. In some embodiments, the concentration of PFAS molecules in the membrane separator permeate effluent is at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 97.5%, and / or at least 99% lower than the concentration of PFAS molecules in the membrane separator residual effluent.

[0122] In some embodiments, at least a portion of the membrane separator residual effluent is recycled (e.g., fed to an upstream membrane separator or the residual side of the same membrane separator). As an example, at least a portion of the membrane separator residual effluent (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, and / or up to 85% by weight, up to 90% by weight, up to 95% by weight, up to 99% by weight, or up to 100% by weight) can be recycled (e.g., via a recirculation process) such that the membrane separator residual input contains at least a portion of the membrane separator residual effluent. For example, in Figures 1C to 1D In this process, all of the membrane separator residual output 155 is recycled (via container 175), such that the membrane separator residual input 160 includes the first membrane separator residual output 155. In some embodiments, the membrane separator is configured to continuously output the membrane separator residual output. In some embodiments, the membrane separator is configured to intermittently output the membrane separator residual output.

[0123] In some embodiments, such as during certain batching processes described below, the aforementioned recycle containing that portion of the membrane separator permeate output is not mixed with the feed before or during the incorporation of at least a portion of the membrane separator permeate input. For example, in some embodiments, during at least a period of time during the liquid removal process, the membrane separator permeate input does not contain the membrane separator permeate output, or it contains less than or equal to 20% by weight, less than or equal to 10% by weight, less than or equal to 5% by weight, less than or equal to 2% by weight, less than or equal to 1% by weight, or less than or equal to 0.1% by weight of the membrane separator permeate output.

[0124] During the recirculation process, according to some embodiments, at least some (or all) of the remaining portion of the membrane separator residual output that is not recirculated back to the membrane separator residual side can become part (or all) of the concentrated output. In some embodiments, the hydraulic pressure of the recirculated membrane separator residual output is increased (e.g., by at least 5%, at least 10%, at least 20%, at least 50%, at least 80%, at least 90%, at least 95%, at least 99%, or more) before becoming part of the membrane separator residual input. Such an increase in pressure can be achieved using any of a variety of techniques, such as the use of a pump.

[0125] In some cases, recirculation processes involving the membrane separator (e.g., incorporating a portion of the membrane separator permeate output into a first membrane separator permeate input) are performed in batches. In some embodiments, the recirculation process is performed continuously. In some embodiments, the recirculation process is performed using a semi-batch process. During batch operation, the hydraulic pressure of the membrane separator permeate input increases over time during operation as a large amount of input is fed to the permeate-side input. In the context of this disclosure, it has been recognized that batch or semi-batch operation of processes involving the membrane separator (e.g., recirculation processes) can reduce the amount of energy required to operate the membrane separator by gradually increasing the concentration of the membrane separator permeate input (and in some cases, the hydraulic pressure), rather than maintaining all membrane separator inputs and / or outputs at high pressure as is typically the case during continuous operation. Such a reduction in energy use can allow PFAS molecules to be removed with higher energy efficiency and / or lower cost (e.g., for final destruction) compared to typical existing PFAS removal technologies.

[0126] In some embodiments, the membrane separator permeate input includes at least a portion of the membrane separator permeate output. For example, in Figure 1C In this embodiment, the membrane separator permeate input 160 comprises at least a portion of the membrane separator permeate output 155. Therefore, since the membrane separator permeate input can contain at least a portion of the membrane separator permeate output, the membrane separator permeate output can advantageously be recycled through the membrane separator, thereby enhancing the separation of PFAS molecules from the residual liquid in the membrane separator permeate output. When the membrane separator permeate output is recycled back into the membrane separator, the concentration of PFAS molecules in the membrane separator permeate output can increase as liquid is removed (e.g., through a permeate semipermeable membrane to the permeate side of the membrane separator). In some embodiments, this advantageously reduces the amount of liquid that may need to be discarded during the removal and / or subsequent degradation of PFAS molecules.

[0127] As described above, some of the systems and methods described herein involve the use of foam grading separators. For example, in Figure 1AIn this system 100, a foam grading separator 130 is included, configured to receive a foam grading separator input 135 and to output a recycled foam grading output 140 and a foam grading product output 150. In some embodiments, the foam grading separator is a fluid device that induces foam formation in at least a portion of the contents of the foam grading separator (e.g., via agitation and / or the introduction of gas and / or surfactants via one or more inlets). After formation, the foam can rise over any remaining liquid and / or other components of the input that cannot participate in foam formation. That is, the foam can exist as a region separate from the remaining liquid within the foam grading separator (e.g., a first region containing foam can be separated from a second region containing liquid). Therefore, in some embodiments, the foam is collected and output from the foam grading separator. For example, in… Figure 1A In this process, the foam grading and recycling output 140 may contain foam formed by a foam grading separator. In some embodiments, at least a portion of the remaining contents of the foam grading separator that did not participate in foam formation is output from the foam grading separator. For example, in Figure 1B In this process, foam grading product output 150 is discharged from foam grading separator 130. In some embodiments, the foam grading separator includes a container that facilitates foam formation and / or separation of foam from any remaining contents within the foam grading separator.

[0128] In some embodiments, the foam grading separator input undergoes a single foam grading cycle. That is, the foam grading separator input may undergo foam grading, and then at least a portion of the contents within the foam grading separator may be transferred to the foam grading recovery output for further processing (i.e., processing unrelated to foam grading), or transferred to the foam grading product output for further processing (i.e., processing unrelated to foam grading). In some embodiments, the foam grading separator is downstream of the membrane separator. In some embodiments, the foam grading separator is upstream of the membrane separator.

[0129] In some embodiments, the foam grading separator input undergoes more than one foam grading cycle. That is, the contents of the foam grading separator input can undergo foam grading, and then a portion of the foam grading output (e.g., foam grading recovery output and / or foam grading product output) can be transferred to the foam grading separator input of the same foam grading separator or another foam grading separator. In some embodiments, the foam grading cycle is performed through a single foam grading separator. In other cases, the foam grading cycle is performed through multiple foam grading separators. For example, a first foam grading cycle can be performed through a first foam grading separator that outputs a first foam grading recovery output, and a second foam grading separator can input a second foam grading separator input containing at least a portion of the first foam grading recovery output to implement a second foam grading cycle. The second foam grading recovery output may contain contaminants (e.g., PFAS and / or surfactants) at a higher concentration than the first foam grading recovery output. In some implementations, the foam grading separator input contains at least a portion of the foam grading recycled output and / or the foam grading product output (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, or more).

[0130] While the foam grading separator input can undergo one or more foam grading cycles, liquefying and / or conveying it to the foam grading unit can be challenging as the input gradually becomes more concentrated. Therefore, in some embodiments, instead of one or more foam grading cycles, the membrane separator can advantageously remove PFAS molecules from the relatively concentrated membrane separator residue input.

[0131] In some embodiments, the foam grading separator includes one or more inlets. In some embodiments, one or more inlets allow the foam grading separator to receive foam grading separator input. In some embodiments, the foam grading separator includes one or more inlets in fluid connection with the permeate side of the membrane separator. For example, in Figure 1A In the middle, the foam grading separator input 135 is fluidly connected to the permeate side 120 of the membrane separator 110 via the inlet 165.

[0132] In some implementations, one or more inlets of the foam grading separator are configured to receive foam grading separator inputs. For example, in Figure 1AIn this embodiment, the foam grading separator 130 receives the foam grading separator input 135 via inlet 165. In some embodiments, the foam grading separator input comprises at least a portion of the membrane separator permeate output (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%, at least 99.9 wt%, or 100 wt%, at least 90 wt%, at least 95 wt%, at least 99 wt%, or up to 100 wt%). In some embodiments, the foam grading separator can remove any residual contaminants that may be present in the membrane separator permeate output. Therefore, the foam grading separator input can be in fluid communication with a portion of the membrane separator permeate output (see [link to relevant documentation]). Figure 8 and Figure 9 ).

[0133] In some implementations, one or more inlets are configured to receive foam grading separator inputs. For example, in Figure 2A In this embodiment, the foam grading separator 130 can receive the foam grading separator input 135 via inlet 165. In some embodiments, the foam grading separator input contains liquid and PFAS molecules. In some embodiments, the foam grading separator input may contain contaminants (e.g., PFAS molecules) at a relatively low concentration. After foam grading of the contents of the foam grading separator input, the foam grading recovery output may have a relatively high concentration of contaminants, such as PFAS molecules. When the membrane separator effluent input contains a portion of the foam grading recovery output having a relatively high concentration of PFAS molecules, removal of PFAS molecules by the membrane separator may be advantageously effective. Therefore, in some embodiments, the membrane separator effluent input contains at least a portion of the foam grading recovery output (e.g., at least 5% by weight, at least 10% by weight, at least 20% by weight, at least 50% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, at least 99% by weight, at least 99.9% by weight, or 100% by weight).

[0134] In some embodiments, the foam grading separator includes one or more inlets, wherein at least one inlet is configured to receive foam grading separator input from the permeate side of the membrane separator. In some embodiments, the foam grading separator input includes a portion of the membrane separator permeate output. For example, in Figure 1AIn this embodiment, the foam grading separator input 135 comprises all of the membrane separator permeate output 145. In some embodiments, the membrane separator permeate output may have a relatively high concentration of PFAS molecules, and the foam grading separator may facilitate the removal and further concentration of PFAS molecules. Therefore, in some embodiments, the foam grading separator input entering the foam grading separator comprises at least a portion of the membrane separator permeate output.

[0135] In some embodiments, the foam grading separator includes one or more outlets. In some embodiments, one or more outlets are configured to output foam grading recovery output. In some embodiments, the foam grading recovery output contains at least some of the PFAS molecules and some of the liquid. In some embodiments, the foam grading recovery output contains at least some of the PFAS molecules, some of the liquid, and some of the surfactant. As mentioned elsewhere in this disclosure, the foam grading recovery output can have a relatively high concentration of PFAS molecules. Therefore, given the relatively high concentration of PFAS molecules in the foam grading recovery output, at least a portion of the foam grading recovery output (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%, at least 99.9 wt%, or 100 wt%) can undergo a destruction process (e.g., a hydrothermal process configured to destroy some of the PFAS molecules) and / or a further concentration process (e.g., using an additional foam grading separator or membrane separator). In some embodiments, the foam grading recovery output contains PFAS molecules, surfactant, and liquid.

[0136] In some implementations, the membrane separator permeate input contains at least a portion of the foam grading and recovery output. For example, in Figure 1B In this system 100, a membrane separator 110 is included that outputs a membrane separator permeate output 145, such that a membrane separator residual input 160 contains at least a portion of the foam fractionation recovery output 140. A foam fractionation separator 130 outputs the foam fractionation recovery output 140. As described elsewhere in this disclosure, in some embodiments, the foam fractionation separator can concentrate PFAS molecules for subsequent removal by the membrane separator. Therefore, since the membrane separator residual input can contain at least a portion of the foam fractionation recovery output, the membrane separator can remove and / or further concentrate any remaining PFAS that has already been concentrated by the foam fractionation separator. Such recycling of the foam fractionation recovery output can promote the concentration of PFAS molecules. In some embodiments, this advantageously reduces the amount of liquid that may need to be discarded during PFAS removal.

[0137] In some embodiments, one or more outlets are configured to output foam grading product outputs. In some embodiments, the foam grading product outputs contain PFAS molecules at a lower concentration than the foam grading separator input. When the contents of the foam grading separator input undergo foam grading, some of the contents (typically the portion containing relatively low concentrations of PFAS) can exit the foam grading separator via the foam grading product outputs. The foam grading product outputs can then undergo further processing (e.g., input into one or more foam grading separators and / or membrane separators) or be used for their intended applications (e.g., urban applications, agricultural applications, environmental applications, or industrial applications and / or for consumption).

[0138] As described above, certain systems and methods described in this disclosure relate to containers. In some embodiments, the container includes a homogenization tank, a variable-volume tank, and / or an air bladder. In some embodiments, the container can facilitate the removal of PFAS molecules by providing a relatively stable source of liquid, PFAS molecules, and / or surfactant to either or both of a membrane separator, a foam grading separator, and / or a surfactant. Furthermore, the container can agitate its contents such that the contents are substantially uniformly dispersed throughout the container's interior. In some embodiments, additives such as surfactants are introduced and / or incorporated (e.g., by mixing, stirring, etc.) into the contents of the container. In some embodiments, the container includes a stirrer, agitator, impeller, and / or other means capable of mixing the contents of the container. In some embodiments, a portion of the surfactant is metered into the container such that it is incorporated with the contents of the container (see [link to relevant documentation]). Figure 7 ).

[0139] In some embodiments, the container includes one or more inlets. In some embodiments, at least one inlet is connected to the foam grading and recycling output material. In some embodiments, some of the one or more inlets are configured to receive at least a portion of the foam grading and recycling output material. For example, in Figure 1D In this container, the foam grading recovery output 140 is received by inlet 190 on container 175. As described elsewhere in this disclosure, a portion of the foam grading recovery output can be reintroduced into the foam grading separator and / or membrane separator to further concentrate contaminants (e.g., PFAS molecules). Therefore, in some cases, the container can store a portion of the foam grading recovery output along with other contents, allowing that portion of the foam grading recovery output to be further processed via such a fluid device. As another example, such as... Figure 2B As shown, container 175 is configured to receive foam grading and recycling output 140 via inlet 190 to facilitate the recycling and / or recovery of foam grading and recycling output 140.

[0140] In some embodiments, at least one inlet of the container is fluidly connected to the permeate side of the membrane separator. In some embodiments, at least one inlet of the container is configured to receive at least a portion of the permeate output from the membrane separator. For example, as... Figure 1D As shown, the membrane separator permeate output 155 is received by container 175 via inlet 180. As another example, such as... Figure 2B As shown, container 175 includes an inlet 180 in fluid connection with membrane separator effluent 155. As described elsewhere in this disclosure, the membrane separator effluent may have a relatively high concentration of PFAS molecules and may undergo further treatment using at least one foam grading separator, at least one membrane separator, or both (e.g., to further concentrate the PFAS molecules). Therefore, in some cases, the container may store a portion of the membrane separator effluent along with other contents, allowing the membrane separator effluent to be further processed via such a fluid device.

[0141] In some implementations, the container includes at least one inlet configured to receive feed. For example, in Figures 1C to 1D In this process, feed 105 is received by container 175 via inlet 185. As previously mentioned, the container can allow a relatively stable source of liquid and PFAS molecules to be introduced into the fluid apparatus (e.g., foam classification unit and / or membrane separation unit) described throughout this disclosure. Thus, the contents of the feed can be stored in the container before the PFAS molecules are removed by the membrane separation element.

[0142] In some implementations, the container includes one or more outlets. For example, such as Figures 1C to 1D As shown, system 100 includes a container 175, which includes an outlet 195 configured to be part of an output membrane separator permeate inlet 160. For example, in Figure 2B In this container, 175 includes an outlet 195 configured to output a portion of the membrane separator permeate input 160. In some embodiments, the container includes one or more outlets configured to output one or more inputs to one or more membrane separators.

[0143] As used herein, two elements are in fluid communication with each other (or equivalently, in fluid communication with each other) when fluid can be supplied from one element to the other without otherwise altering the configuration of the elements or the configuration of elements (e.g., valves) between these elements. Two conduits connected by an open valve (thus allowing fluid to flow between the two conduits) are considered to be in fluid communication with each other. Conversely, two conduits separated by a closed valve (thus preventing fluid from flowing between the conduits) are not considered to be in fluid communication with each other.

[0144] As used herein, two elements are fluidly connected when they are joined such that they are in fluid communication with each other in at least one configuration of the element and any intermediate element. Two membrane separators connected by a valve and a conduit that allows flow between the membrane separators in at least one configuration of the valve will be considered fluidly connected with each other. To further illustrate, two membrane separators connected by a valve and a conduit that allows flow between the membrane separators in a first valve configuration but not in a second valve configuration will be considered fluidly connected with each other both when the valve is in the first configuration and when the valve is in the second configuration. Conversely, two membrane separators not connected to each other in a manner that would allow fluid to be delivered between the two membrane separators in any configuration (e.g., via a valve, another conduit, or another component) will not be considered fluidly connected with each other. Elements in fluid communication with each other are always fluidly connected with each other, but not all elements fluidly connected with each other must be in fluid communication with each other.

[0145] Various components are described herein as fluid connections. Fluid connections can be direct or indirect. Generally, a direct fluid connection exists between the first and second regions (and the two regions are referred to as directly fluid connected) when the composition of the fluid in the second fluid connection is substantially unchanged relative to the composition of the fluid in the first fluid connection (i.e., the weight percentage of a fluid component present in the first fluid connection in the second fluid connection differs from the weight percentage of that component in the first fluid connection by no more than 5%). As an exemplary example, a flow connecting the first and second unit operations, wherein the pressure and temperature of the fluid are regulated but the composition of the fluid remains unchanged, will be referred to as directly fluid connected first and second unit operations. On the other hand, a flow will not be referred to as directly fluid connected first and second unit operations if a separation step that significantly alters the composition of the flow contents during the flow from the first component to the second component and / or a chemical reaction that significantly alters the composition of the flow contents during the flow from the first component to the second component is performed. In some embodiments, a direct fluid connection between the first and second regions can be configured such that the fluid does not undergo a phase change from the first region to the second region. In some embodiments, a direct fluid connection can be configured such that at least 50% by weight (or at least 75% by weight, at least 90% by weight, at least 95% by weight, at least 98% by weight, or up to 100% by weight) of the material (e.g., liquid, surfactant, PFAS, etc.) in the first region is delivered to the second region via the direct fluid connection. In some embodiments, any of the fluid connections described herein can be a direct fluid connection. In other cases, the fluid connection can be an indirect fluid connection.

[0146] Although Figures 1A to 1D and Figures 2A to 2B This includes both membrane separators and foam grading separators; however, the use of foam grading separators is optional, and in some embodiments, only membrane separators may be used. An example of such an embodiment is shown in… Figure 5 In. Figure 5 In this process, a membrane separator permeate input containing at least some surfactant, PFAS molecules, and liquid enters a membrane separator comprising a semipermeable membrane. A portion of the membrane separator permeate input then exits the membrane separator via a membrane separator permeate output. Another portion of the membrane separator permeate input contacts and is conveyed through the semipermeable membrane, exiting via a membrane separator permeate output. Figure 5 In this context, the permeate input of the membrane separator also includes the feed material.

[0147] Figure 6 The image shows another example of an implementation in which the foam grading separator is an optional feature. Figure 6 and Figure 5 Essentially the same, the difference being that a portion of the membrane separator residual effluent is recirculated and enters the membrane separator via the membrane separator residual input. Another portion of the membrane separator residual effluent may not be incorporated into the membrane separator residual input used for recirculation, and thus can form the membrane separator residual retained effluent. The membrane separator residual retained effluent is essentially removed from the system (e.g., leaves).

[0148] Although Figures 1C to 1D This includes foam grading separators, membrane separators, and containers; however, as previously stated, the use of foam grading separators is optional. In some embodiments, membrane separators can be used with containers without foam grading separators. For example, as... Figure 7 As shown, the membrane separator is used with the container. Figure 6 Similarly, the membrane separator residual effluent leaving the membrane separator is recycled, causing a portion of the contents of the membrane separator residual effluent to enter the membrane separator residual influent. For example... Figure 7 As shown, a portion of the membrane separator residual output enters a container, which outputs a membrane separator residual input containing a portion of the membrane separator residual output. Figure 7 Also shown is a portion of the membrane separator residue output that is not incorporated into the container and forms the membrane separator residue retentate output. In some embodiments, a surfactant is metered into the container such that a portion of the surfactant enters the membrane separator via the membrane separator residue input. Turning back... Figure 7 The surfactant enters the container, and a portion of the surfactant exits the container via the membrane separator and the residue inlet. The feed also enters the container, allowing both the feed and the surfactant to exit the container via the membrane separator and enter the membrane separator.

[0149] In some implementations, the system includes a foam grading separator, a container, and a membrane separator, allowing a portion of the PFAS molecules to exit the system for destruction. For example, as... Figure 8 As shown, a foam grading separator input containing PFAS molecules and liquid enters the foam grading separator. The foam grading separator input also includes feed. Foam grading product output and foam grading recovery output exit the foam grading separator. The foam grading recovery output enters a container, and a surfactant is added to the container, such that the membrane separator permeate input exiting the container contains PFAS molecules, surfactant, and liquid. The membrane separator permeate output containing a relatively concentrated stream of PFAS molecules enters the container, such that the membrane separator permeate output is recycled. The membrane separator permeate output is also recycled, such that the membrane separator permeate output enters the foam grading separator for further treatment. Figure 8 As further shown, a portion of the PFAS molecules within the system can leave the container for subsequent PFAS destruction, and any portion of the PFAS molecules remaining from PFAS destruction can be reintroduced into the container for further processing via membrane separators and / or foam grading separators.

[0150] Figure 9 Another example of a system including foam grading separators, containers, and membrane separators is shown. Figure 9 and Figure 8 Essentially the same, the difference being that the feed containing PFAS molecules and liquid enters the container, and the foam grading separator is located downstream of the membrane separator, rather than as... Figure 8 The upstream shown.

[0151] As described above, in some embodiments, the membrane separator comprises one or more semi-permeable membranes connected in series. For example, Figure 10 and Figure 4C They are basically the same, the difference is that Figure 10 Only two semipermeable membranes are shown, instead of... Figure 4C The three shown Figure 10 Two semipermeable membranes connected in series by fluid were depicted.

[0152] In some implementations, two or more semipermeable membranes can be connected in series, such that the permeate output from the membrane separator contacts the second semipermeable membrane. For example, as... Figure 11 As shown, a membrane separator permeate input containing PFAS molecules, a liquid, and a surfactant enters the membrane separator and is conveyed through a semipermeable membrane to form a membrane separator permeate output exiting the membrane separator. The membrane separator permeate output then enters another membrane separator as a membrane separator permeate input. A portion of the membrane separator permeate output is also shown for recycling.

[0153] In some implementations, two or more surfactants are used. For example, such as Figure 12 As shown, Figure 12 and Figure 11 Essentially the same, the difference being the introduction of surfactants (e.g., surfactants with the same and / or different compositions) between the semipermeable membranes and the recycling of the permeate output from each membrane separator back into the respective semipermeable membrane. In some embodiments, each surfactant can be a specific set of contaminants (e.g., a first surfactant can be used to remove relatively large PFAS molecules, and a second surfactant can be used to remove relatively small PFAS molecules).

[0154] In some embodiments, the system includes: a membrane separator comprising at least one semipermeable membrane defining a permeate side and a residual side of the membrane separator, wherein the residual side of the membrane separator is configured to receive a membrane separator residual input comprising perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, a liquid, and a surfactant; and a foam grading separator comprising: an inlet fluidly connected to the permeate side of the membrane separator and configured to receive a foam grading separator input; and one or more outlets configured to: output a foam grading product output with a PFAS molecule concentration lower than that of the foam grading separator input, and output a foam grading recovery output comprising at least some of the PFAS molecules and at least some of the surfactant. For example, in Figure 1A In the system 100, the membrane separator 110 includes at least one semipermeable membrane 125 defining a permeate side 120 and a residual side 115 of the membrane separator 110, wherein the residual side 115 of the membrane separator 110 is configured to receive a membrane separator residual input 160 comprising perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, a liquid, and a surfactant; and a foam grading separator 130, the foam grading separator 130 including: [missing information - likely related to the membrane separator 110]. The permeate side 120 of 10 is fluidly connected and configured to receive the inlet 165 of the foam grading separator input 135; one or more outlets 170A to 170B, the one or more outlets 170A to 170B being configured to: output foam grading product output 150 with a PFAS molecule concentration lower than that of the foam grading separator input 135, and output foam grading recycling output 140, the foam grading recycling output 140 containing at least some of the PFAS molecules and at least some of the surfactants.

[0155] In some embodiments, the system includes: a membrane separator comprising at least one semipermeable membrane defining a permeate side and a residual side of the membrane separator, wherein the residual side of the membrane separator is configured to receive a membrane separator residual input comprising at least a portion of foam grading recovery output, the foam grading recovery output comprising perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, a liquid, and a surfactant; and a foam grading separator comprising: one or more inlets configured to receive the foam grading separator input; and one or more outlets configured to output foam grading product output with a PFAS molecule concentration lower than that of the foam grading separator input, and output foam grading recovery output. For example, in Figure 2AIn the system 100, a membrane separator 110 is included, the membrane separator 110 including at least one semipermeable membrane 125 defining a permeate side 120 and a residual side 115 of the membrane separator 110, wherein the residual side 115 of the membrane separator 110 is configured to receive a membrane separator residual input 160 comprising at least a portion of a foam grading recovery output 140, the foam grading recovery output 140 comprising perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, liquids, and surfactants. The agent; and a foam grading separator 130, the foam grading separator 130 comprising: one or more inlets 165 configured to receive foam grading separator input 135; and one or more outlets 170A to 170B configured to output foam grading product output 150 with a concentration of PFAS molecules lower than that of foam grading separator input 135, and output foam grading recycled output 140.

[0156] In some embodiments, the method includes: removing a quantity of PFAS molecules from a feed comprising a liquid and perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, wherein the removal comprises: conveying a membrane separator permeate input to the permeate side of a membrane separator, the membrane separator permeate input comprising at least a portion of the feed and a surfactant, the presence of the surfactant causing at least some of the PFAS molecules to associate with micelles containing the surfactant, such that: a membrane separator permeate output exits from the permeate side of the membrane separator, and at least a portion of the liquid from the membrane separator permeate input is conveyed from the permeate side of the membrane separator through the semipermeable membrane of the membrane separator to the permeate side of the membrane separator to form a portion or all of the membrane separator permeate output having a PFAS molecule concentration less than that of the membrane separator permeate input; wherein the membrane separator permeate input comprises at least a portion of the membrane separator permeate output, the membrane separator permeate output comprising at least some of the PFAS molecules conveyed to the permeate side of the membrane separator. For example, in Figure 3The method includes: removing a quantity of PFAS molecules from a feed 105 containing liquid and perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, wherein the removal includes: conveying a membrane separator permeate input 160 to the permeate side 115 of a membrane separator 110, the membrane separator permeate input 160 containing at least a portion of the feed 105 and a surfactant, the presence of which causes at least some of the PFAS molecules to associate with micelles containing the surfactant, such that: a membrane separator permeate output 155 exits the permeate side 115 of the membrane separator 110 and from the membrane separator permeate... At least a portion of the liquid in the residual input 160 is transported from the residual side 115 of the membrane separator 110 through the semipermeable membrane 125 of the membrane separator 110 to the permeate side 120 of the membrane separator 110 to form part or all of the membrane separator permeate output 145 in which the concentration of PFAS molecules is less than the concentration of PFAS molecules in the membrane separator residual input 160; wherein the membrane separator residual input 160 includes at least a portion of the membrane separator residual output 155, which includes at least some of the PFAS molecules transported to the residual side 115 of the membrane separator 110.

[0157] The following examples are intended to illustrate certain embodiments of the present invention, but do not represent the full scope of the invention.

[0158] Example 1

[0159] This embodiment describes the separation of PFAS from water.

[0160] To determine the effect of surfactant dosage on the removal of PFAS molecules from the feed using micellar-enhanced filtration (MEF), several different concentrations of surfactant were metered into the feed, and the feed was filtered to remove PFAS molecules using a micellar-enhanced filtration (MEF) system comprising a membrane surface area of ​​approximately 0.00006 m². 2Ultrafiltration membranes (e.g., zwitterionic semipermeable membranes) were used. No foam grading separators were used in this embodiment. The removal efficiency of the selected PFAS molecules was then calculated based on the concentrations of the selected PFAS molecules in the feed and the selected PFAS molecules in the permeate. In this experiment, the cationic auxiliary surfactant hexadecyltrimethylammonium bromide (CTAB) was added to the feed water at a concentration of 200 mg / L. The feed water containing PFAS molecules and the surfactant was treated using an MEF system. Table 1 describes the MEF removal efficiencies of various PFAS molecules, including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), perfluorobutane sulfonic acid (PFBS), and perfluorobutyric acid (PFBA). The concentrations of these compounds in the feed water and permeate are also shown in Table 1. PFAS molecules with relatively long chain lengths (including PFOA, PFOS, PFHxS, and PFBS) were removed from the feed water with an efficiency greater than or equal to 99.0%. However, PFAS molecules with relatively short chain lengths are less efficient, for example, PFBA with a removal efficiency of 84%.

[0161] Table 1. Removal efficiency of MEF for PFAS molecules at a dose of 200 mg / L of auxiliary surfactant.

[0162]

[0163] To determine whether higher surfactant concentrations improved removal efficiency, a second set of experiments was conducted in which CTAB was added to the feed water at a relatively high concentration of 350 mg / L. The feed water and surfactant were treated in a similar manner using a MEF system. The removal efficiencies of the compounds and their concentrations in the feed water and permeate are shown in Table 2. PFAS molecules with relatively long chain lengths (including PFOA, PFOS, and PFHxS) exhibited removal efficiencies greater than or equal to 99.6%, which was higher than that observed at a CTAB dose of 200 mg / L. However, those with relatively short chain lengths were not effectively removed. PFBS and PFBA showed removal efficiencies of 98.8% and 83.7%, respectively, which were lower than those observed at a CTAB dose of 200 mg / L.

[0164] Table 2. Removal efficiency of PFAS molecules by MEF at a dose of 350 mg / L auxiliary surfactant.

[0165]

[0166] A third set of experiments was conducted, in which the concentration of CTAB was further increased to 1000 mg / L, and the resulting feed water and surfactant were treated using a MEF system. The results are summarized in Table 3. These compounds (including PFBS and PFBA), which experienced a decrease in removal efficiency as the concentration of the auxiliary surfactant increased from 200 mg / L to 350 mg / L, were removed with a removal efficiency greater than or equal to 98%. Surprisingly, under these conditions, PFAS molecules with relatively short chain lengths were removed with relatively high efficiency. Specifically, PFBS and PFBA exhibited removal efficiencies of 99.6% and 98.0%, respectively. Therefore, based on the experiments described herein, PFAS molecules (including those with relatively short chain lengths, such as PFBS and PFBA) can be effectively removed from feed water containing PFAS molecules using some embodiments of the systems and methods described throughout this disclosure.

[0167] Table 3. Removal efficiency of MEF for PFAS molecules at a dose of 1000 mg / L of auxiliary surfactant.

[0168]

[0169] Example 2

[0170] This embodiment describes the separation of PFAS from water and the restricted separation of ions (e.g., sulfate) from water.

[0171] Aqueous solutions containing PFAS can also contain relatively large amounts of ions, such as sulfate. However, such ions can scale on semipermeable membranes and negatively impact the efficiency of downstream oxidation systems due to side reactions and / or reduced hydroxyl (OH) generation. Therefore, it may be desirable to use semipermeable membranes and appropriate surfactant concentrations to separate PFAS from the waste stream while limiting sulfate separation. In some cases, it may be particularly desirable for PFAS removal systems to remove PFBA (small PFAS compounds that are generally known to be difficult to separate from aqueous solutions), while limiting the retention of sulfate and / or other ions.

[0172] Semipermeable membranes with various MWCOs were tested to determine the appropriate MWCO for both desired PFAS separation and restricted ion separation. The MWCOs of the tested semipermeable membranes are shown in Table 4 and correspond to... Figures 13A to 13G The MWCO values ​​are shown on the x-axis. These tests were conducted at three different surfactant concentrations: 0 ppm, 350 ppm, and 1000 ppm. The surfactant used in this example was CTAB. An aqueous solution containing PFAS, CTAB, and sulfate ions derived from calcium sulfate (CaSO4) was transported through a membrane with a membrane area of ​​approximately 2 m². 2up to 3 m 2 After the membrane separator of the 2.5-inch membrane module was installed, the concentrations of PFAS molecules and sulfate ions were determined, and their respective percentage rejection rates were calculated. To determine the dependence of the percentage rejection rate on the MWCO of the semipermeable membrane, a logarithmic trend line was fitted to each dataset, where each dataset represents tests conducted at different surfactant concentrations. To generate the logarithmic trend line, membranes with different MWCOs were assigned values ​​from 1 to 8, where 1 corresponds to the lowest MWCO and 8 corresponds to the highest MWCO. These values ​​were used as the independent variable (x) in the trend line fitting, and the percentage rejection rate from the data was used as the dependent variable (y) in the trend line fitting. Then, for each surfactant concentration, a logarithmic trend line was fitted to the percentage rejection rate data using an equation of the form y = Aln(x) + B (where A and B are coefficients to be fitted, ln is the natural logarithm, x is the membrane value discussed above, and y is the percentage rejection rate). Figures 13A to 13G The percentage retention rates shown are generated from the best-fit curve of the trendline fitting and are calculated using the logarithmic equation generated by the fitting as a function of the MWCO of each semipermeable membrane.

[0173] The logarithmic trend line fitting of the retention percentage of PFBA in the permeate output of the membrane separator is shown in the figure. Figure 13A The logarithmic trend line fitting of sulfate retention percentage in the permeate output from the membrane separator is shown in the figure. Figure 13B In the middle. For example Figures 13A to 13B As shown, at CTAB doses greater than or equal to 350 ppm, PFBA was retained by semipermeable membranes with a retention percentage greater than 60%, while sulfate retention was limited to below 60%. Retention percentages of other PFAS compounds (e.g., PFNA, PFOA, PFOS, PFBS, and PFHxS) were also tested under similar conditions. The logarithmic trendline fit results for these tests are shown in [Figure / Insert Figure ... Figures 13C to 13G middle.

[0174] Table 4. MCWO values ​​of the semipermeable membranes tested in this embodiment.

[0175]

[0176] While several embodiments of the invention have been described and illustrated herein, those skilled in the art will readily conceive of a variety of other means and / or structures for performing the functions described herein and / or obtaining the results and / or one or more advantages described herein, and each of such variations and / or modifications is considered to be within the scope of the invention. More generally, those skilled in the art will readily understand that all parameters, dimensions, materials, and configurations described herein are intended to be exemplary, and actual parameters, dimensions, materials, and / or configurations will depend on one or more specific applications using the teachings of the invention. Those skilled in the art will recognize, or can determine, many equivalents of the specific embodiments of the invention described herein using only conventional experimentation. Therefore, it should be understood that the foregoing embodiments are presented by way of example only, and the invention can be practiced in ways other than those specifically described and claimed within the scope of the appended claims and their equivalents. The invention relates to the various individual features, systems, articles, materials, and / or methods described herein. Furthermore, any combination of two or more such features, systems, articles, materials, and / or methods is included within the scope of the invention if such features, systems, articles, materials, and / or methods are not inconsistent with each other.

[0177] Unless explicitly stated otherwise, nouns without quantifiers as used herein in the specification and claims shall be understood to mean “at least one / a kind”.

[0178] The phrase “and / or” as used herein in the specification and claims should be understood to mean “any one or both” of the elements so connected, i.e., elements that coexist in some cases and exist separately in others. Unless explicitly stated to the contrary, additional elements may optionally exist besides those specifically indicated by the “and / or” clause, whether related to or unrelated to those specifically indicated. Thus, as a non-limiting example, when used in conjunction with open-ended language such as “comprising / including,” reference to “A and / or B” may refer to A without B (optionally including elements other than B) in one embodiment; in another embodiment, it may refer to B without A (optionally including elements other than A); in yet another embodiment, it may refer to both A and B (optionally including other elements); and so on.

[0179] As used herein in the specification and claims, “or” should be understood to have the same meaning as “and / or” as defined above. For example, when items in a list are separated, “or” or “and / or” should be interpreted as inclusive, that is, including multiple elements or at least one of the elements in the list, but also including more than one, and optionally additional items not listed. Terms that explicitly indicate the opposite, such as “only one” or “exactly one”, or when used in a claim, “consisting of”, will refer to including multiple elements or exactly one of the elements in the list. Generally, when preceded by exclusive terms such as “one of,” “one of,” “only one of,” or “exact one of,” the term “or” as used herein should only be interpreted as indicating an exclusive choice (i.e., one or the other, but not both). When used in a claim, “consisting substantially of” should have the ordinary meaning as it is used in the field of patent law.

[0180] As used herein in the specification and claims, the phrase "at least one" when referring to a list of one or more elements should be understood to mean at least one element selected from any one or more elements in the list, but does not necessarily include all the elements specifically listed in the list and at least one of each element, and does not exclude any combination of elements in the list. This definition also allows for the optional presence of elements other than those specifically indicated in the list of elements referred to by the phrase "at least one," whether related to or unrelated to those specifically indicated elements. Therefore, 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") in one embodiment may refer to at least one A, optionally including more than one A, while B is absent (and optionally including elements other than B); in another embodiment, it may refer to at least one B, optionally including more than one B, while A is absent (and optionally including elements other than A); in yet another embodiment, it may refer to at least one A, optionally including more than one A, and at least one B, optionally including more than one B (and optionally including other elements); and so on.

[0181] As used in this article, "weight%" is an abbreviation for weight percentage. As used in this article, "at%" is an abbreviation for atomic percentage.

[0182] Some implementations may embody the methods described in various embodiments. Actions performed as part of a method may be ordered in any suitable manner. Therefore, implementations in which actions are performed in a different order than those shown may be constructed, which may include actions that differ from those described (e.g., more or fewer), and / or may involve performing some actions simultaneously, even if the actions are shown to be performed sequentially in the implementations specifically described above.

[0183] The use of ordinal terms such as “first,” “second,” “third,” etc., in claims to modify a claim element does not imply any priority, order of precedence, or sequence of actions of a method relative to another claim element. Rather, it is merely used as a marker to distinguish one claim element with a certain name from another element with the same name (but using an ordinal term), thereby differentiating the claim elements.

[0184] In the claims and the foregoing description, all transitional phrases such as “comprising,” “including,” “with,” “having,” “containing,” “involving,” “holding,” etc., shall be understood as open-ended, meaning including but not limited to. As set forth in Section 2111.03 of the U.S. Patent Examination Procedure Manual, only the transitional phrases “consisting of” and “substantially consisting of” shall be closed or semi-closed transitional phrases, respectively.

Claims

1. A system comprising: A membrane separator comprising at least one semipermeable membrane defining a permeate side and a residual side of the membrane separator, wherein the residual side of the membrane separator is configured to receive a membrane separator residual input comprising perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, a liquid, and a surfactant. as well as Foam grading separator, the foam grading separator comprising: An inlet, which is fluidly connected to the permeate side of the membrane separator and configured to receive foam grading separator input; as well as One or more outlets, said one or more outlets being configured to: The output of foam-graded product has a PFAS molecule concentration lower than that of the foam grading separator input. The output foam grading and recycling output contains at least some of the PFAS molecules and at least some of the surfactants.

2. A system comprising: A membrane separator comprising at least one semipermeable membrane defining a permeate side and a residual side of the membrane separator, wherein the residual side of the membrane separator is configured to receive a membrane separator residual input comprising at least a portion of foam grading recovery output, the foam grading recovery output comprising perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, a liquid, and a surfactant. as well as Foam grading separator, the foam grading separator comprising: One or more entry points, wherein the one or more entry points are configured to: Receive the input material for the foam grading separator; as well as One or more outlets, said one or more outlets being configured to: The output of foam-graded product has a PFAS molecule concentration lower than that of the foam grading separator input. Output the foam graded recycling output.

3. A system comprising: A membrane separator, comprising at least one semi-permeable membrane and configured to: Receives membrane separator residue input containing perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, surfactants, and liquids; and At least a portion of the PFAS molecules are removed from the permeate input of the membrane separator.

4. The system according to any one of claims 1 to 3 further includes a container.

5. The system of claim 4, wherein the container includes one or more inlets configured to receive feed and / or the foam grading and recovery output and an outlet fluidly connected to the permeate side of the membrane separator.

6. The system according to any one of claims 4 to 5, wherein the container further comprises at least one inlet connected to the foam grading and recycling output stream.

7. The system according to any one of claims 1 to 6, wherein the foam grading separator further comprises at least one inlet configured to receive foam grading separator input from the permeate side of the membrane separator.

8. The system according to any one of claims 1 to 7, wherein the membrane separator is further configured to produce a membrane separator permeate output, and the concentration of PFAS molecules in the membrane separator permeate output is at least 90% lower than the concentration of PFAS molecules in the membrane separator residual input.

9. The system according to any one of claims 1 to 8, wherein the system comprises two or more membrane separators fluidly connected to each other.

10. The system according to any one of claims 1 to 9, wherein the membrane separator is configured to output membrane separator permeate output.

11. The system of claim 10, wherein the container further comprises at least one inlet connected to the membrane separator residual discharge stream.

12. The system according to any one of claims 10 to 11, wherein the membrane separator is configured to continuously output the membrane separator permeate output.

13. The system according to any one of claims 10 to 12, wherein the membrane separator is configured to intermittently output the membrane separator permeate output.

14. The system according to any one of claims 1 to 13, wherein the membrane separator comprises an electrically neutral membrane.

15. The system according to any one of claims 1 to 14, wherein the membrane separator comprises a zwitterion membrane.

16. The system according to any one of claims 1 to 15, wherein the membrane separator comprises an ultrafiltration membrane.

17. The system according to any one of claims 1 to 16, wherein the surfactant comprises CTAB.

18. The system according to any one of claims 1 to 17, wherein the MWCO of the semipermeable membrane is greater than or equal to 200 Da and less than or equal to 5000 Da.

19. The system according to any one of claims 1 to 18, wherein the concentration of the surfactant in the membrane separator residue input is greater than or equal to 100 mg / L and less than or equal to 1000 mg / L.

20. The system according to any one of claims 1 to 19, wherein the concentration of the surfactant in the membrane separator residue input is greater than or equal to 200 mg / L and less than or equal to 360 mg / L.

21. The system according to any one of claims 1 to 20, wherein the liquid comprises water.

22. A method comprising: Removing a certain amount of said PFAS molecules from a feed containing liquid and perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules, wherein said removal includes: A membrane separator permeate feedstock is delivered to the permeate side of the membrane separator, the membrane separator permeate feedstock comprising at least a portion of the feed and a surfactant, the presence of which causes at least some of the PFAS molecules to associate with micelles containing the surfactant, such that: The residual material from the membrane separator exits the residual material side of the membrane separator, and At least a portion of the liquid from the residual input of the membrane separator is transported from the residual side of the membrane separator through the semipermeable membrane of the membrane separator to the permeate side of the membrane separator to form part or all of the permeate output of the membrane separator in which the concentration of PFAS molecules is less than the concentration of PFAS molecules in the residual input of the membrane separator. The membrane separator residual input includes at least a portion of the membrane separator residual output, and the membrane separator residual output includes at least some of the PFAS molecules delivered to the residual side of the membrane separator.

23. A method comprising: A membrane separator effluent input containing a liquid and perfluoroalkyl and / or polyfluoroalkyl (PFAS) molecules associated with micelles containing a surfactant is contacted with a semipermeable membrane, such that at least a portion of the PFAS is removed from the liquid and a membrane separator effluent output is formed.

24. The method according to any one of claims 22 to 23, wherein the membrane separator residue input comprises at least a portion of the membrane separator residue output.

25. The method according to any one of claims 22 to 24, wherein the membrane separator residual input comprises at least a portion of the foam grading recovery output exiting the foam grading separator.

26. The method of claim 25, wherein the foam grading input entering the foam grading separator comprises at least a portion of the membrane separator permeate output.

27. The method according to any one of claims 22 to 26, wherein the membrane separator is configured to continuously output the membrane separator permeate output.

28. The method according to any one of claims 22 to 27, wherein the membrane separator is configured to intermittently output the membrane separator permeate output.

29. The method according to any one of claims 22 to 28, wherein the membrane separator is fluidly connected to the second membrane separator.

30. The method according to any one of claims 22 to 29, wherein the membrane separator comprises an electrically neutral membrane.

31. The method according to any one of claims 22 to 30, wherein the membrane separator comprises a zwitterion membrane.

32. The method according to any one of claims 22 to 31, wherein the membrane separator comprises an ultrafiltration membrane.

33. The method according to any one of claims 22 to 32, wherein the surfactant comprises CTAB.

34. The method according to any one of claims 22 to 33, wherein the MWCO of the semipermeable membrane is greater than or equal to 200 Da and less than or equal to 5000 Da.

35. The method according to any one of claims 22 to 34, wherein the concentration of the surfactant in the membrane separator residue input is greater than or equal to 100 mg / L and less than or equal to 1000 mg / L.

36. The method according to any one of claims 22 to 35, wherein the concentration of the surfactant in the membrane separator residue input is greater than or equal to 200 mg / L and less than or equal to 360 mg / L.

37. The method according to any one of claims 22 to 36, wherein the molecular weight of the micelles is less than or equal to 3000 Da.

38. The method according to any one of claims 22 and 24 to 37, wherein the concentration of PFAS in the membrane separator permeate output is at least 90% lower than the concentration of PFAS in the membrane separator residue input.

39. The method according to any one of claims 22 to 38, wherein the membrane separator residue input comprises water.

40. The method according to any one of claims 22 to 39, wherein the membrane separator residue input contains dissolved sulfate ions.

41. The method of claim 40, wherein the semipermeable membrane allows at least a portion of the dissolved sulfate ions to be transported from the permeate side of the membrane separator to the permeate side of the membrane separator.

42. The method according to any one of claims 40 to 41, wherein the ratio of the percentage of PFAS molecules rejected by the membrane separator to the percentage of dissolved sulfate ions rejected by the membrane separator is greater than 1.

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