Chemical destruction processes of pfas in environmental media

Abstract

Systems and methods are provided for the destruction and disposal of fluorinated materials (e.g., PFAS) while reducing gaseous PFC emissions. The method can be applied in a batch reactor or in situ to soil or other environmental media containing PFAS, such as at a soil site. The method may include mixing PFAS, a hydroxide base, and optionally a solvent in a batch reactor to form a suspension. The reaction mixture can be heated to a temperature of 25°C to 400°C for about 0.5 hours to 240 hours to defluorinate the corresponding PFAS fluorocarbons and produce defluorinated waste products. Alternatively, the suspension can be maintained at room temperature for a sufficient time. Alternatively, a hydroxide base and optionally a solvent can be sprayed onto the PFAS and optionally heated. This method converts organic fluorine present in PFAS-contaminated soil into inorganic fluorides.

Description

[0001] Cross-references to related applications

[0002] This PCT patent application claims the benefit and priority of U.S. Nonprovisional Application Serial No. 18 / 888,350, filed September 18, 2024; U.S. Provisional Patent Application Serial No. 63 / 544,544, filed October 17, 2023; U.S. Provisional Patent Application Serial No. 63 / 602,736, filed November 27, 2023; U.S. Provisional Patent Application Serial No. 63 / 555113, filed February 19, 2024; and U.S. Provisional Patent Application Serial No. 63 / 655,844, filed June 4, 2024, the entire disclosure of which is incorporated herein by reference. Background Technology 1. Technical Field

[0004] The present invention generally relates to systems and methods for destroying and disposing of fluorocarbon compounds or fluorinated materials, such as perfluoroalkyl and polyfluoroalkyl substances (PFAS) deposited in environmental media such as soil, granular activated carbon (GAC), and / or biological solids. 2. Background Technology

[0006] Fluorocarbons and fluorinated substances such as perfluoroalkyl and polyfluoroalkyl substances (PFAS) are man-made materials used for over 90 years (1) and have been found in water at concentrations harmful to humans (2). Since 2000, PFAS have been designated as emerging pollutants of concern (3). They can bioaccumulate in the human body (4,5,6), have been linked to certain cancers, and have a wide range of harmful effects, including hormone and immune system interference, ulcerative colitis, and endocrine disorders (7,8,9), to name just a few.

[0007] PFAS comprise a diverse class of chemicals that, due to their low surface tension and wetting properties, are found in a wide range of products and processes, including fluoropolymers, liquid repellents for paper, packaging, textiles, leather, and carpet products, industrial surfactants, additives, coatings, and fire-fighting foams (10). Fluoropolymers such as polytetrafluoroethylene (PTFE) are considered the most common PFAS for computer applications and surface coatings.

[0008] The US Environmental Protection Agency (USEPA) CompTox database has identified more than 9,000 highly fluorinated substances with Chemical Abstracts Service (CAL) numbers available on the global market, most of which are fluorinated polymers and fluorinated surfactants (11).

[0009] The latest guidance, which came into effect on June 25, 2024, has recommended limits for PFOA (12,13) ​​and PFOS at 4 parts per trillion (ppt). Based on risk-based values ​​at regional screening level (RSL), USEPA has added five additional PFAS compounds for site remediation (perfluorononanoic acid (PFNA), PFHxS, perfluorononanoate, perfluorooctanoate, and perfluorohexanesulfonate) (3).

[0010] Various technologies have been used to decompose or dispose of hazardous substances, such as by electrochemical oxidation, direct irradiation, plasma treatment, photocatalysis, ultrasonic decomposition, supercritical water oxidation, reduced hydrogen defluorination and thermal degradation / incineration (14).

[0011] In 2020, the US EPA (15) published a technical brief on the incineration of PFAS, with the main conclusion that the effectiveness of incineration in destroying PFAS and its fate in the formation of potential mixed fluorinated organic byproducts were not clearly understood. A major concern is that incomplete destruction of PFAS may lead to the formation of PICs (products of incomplete combustion), such as smaller PFAS molecules, which could be a potential hazard. Only a few studies related to PFAS incineration are available at full-scale operating facilities (16, 17–19). According to Solo-Gabriele et al., increasing the incinerator temperature reduced the total concentration of PFAS treated. However, not all PFAS substances decreased with increasing temperature (17). There have been alarming reports of higher concentrations of PFOA found in the air at incinerator sites compared to upwind sites (18). Public concern is that incineration may spread PFAS without breaking them down. The publication claims that preliminary data show soil and surface water near a commercial facility in Cohos, New York, where PFAS-containing fire-fighting foam has been burned, were contaminated with PFAS (20).

[0012] PFAS incineration can be carried out directly on PFAS-based materials (e.g., fire-fighting foam) or indirectly through the incineration of PFAS-containing waste (e.g., textiles, etc.) (21). Recently, the Department of Defense issued a ban on the incineration of PFAS-containing items, with particular emphasis on aqueous film-forming foams frequently used in training and operational scenarios (22). Furthermore, the military is now prohibited from incinerating PFAS-containing materials under the 2022 National Defense Authorization Act (23) and the Clean Air Act (24). Most incineration studies have monitored a limited number of compounds, leaving the question of “unmonitored” PFAS unanswered (25). Despite numerous studies on the thermal degradation of PFAS (26,27,28,29,30), only limited data (31,32) are available regarding the direct detection of degradation products during on-site large-scale incineration. The main obstacles remain the lack of suitable emission sampling methods (including industrial site sampling) for capturing PFAS compounds and analytical methods for identifying / detecting PFAS and their thermal decomposition byproducts. The question of how significant the proportion of unanalyzed volatiles is remains unanswered.

[0013] Thermal degradation / incineration is a widely available method for managing pollutants in solid, liquid, or gaseous form using existing incineration facilities (33), and many incineration facilities have been used, intentionally or unintentionally, to treat PFAS (e.g., consumer products, activated carbon regeneration). As previously mentioned, incineration facilities have been deployed and are well established in industry.

[0014] Therefore, the initial cost of implementing this technology is significantly lower compared to other PFAS-destructive technologies. In summary, these advantages make it a key solution for managing PFAS-containing waste (34,35).

[0015] However, in general, waste byproducts from any incineration include bottom ash containing unburned products and gases containing fine particles and volatile products (34). According to Wang et al. (34) on PFAS incineration, both the resulting ash and gases are problematic. The ash contains inorganic fluorine and residual PFAS bound to inorganic compounds such as calcium. The ash is typically sent to landfills or reused. Particulate matter in the gas can be captured using electrostatic precipitators. However, HF is expected to be a major product of the thermal conversion of PFAS during incineration and is a corrosive / acidic gas. Capturing or removing volatile fluoride-containing byproducts may also be problematic.

[0016] Any untreated PFAS or byproducts from incineration are directly released into the environment (34). Therefore, the potential risks of secondary air and soil pollution, as well as the return of PFAS to the environment, are very high. Furthermore, incomplete destruction during thermal treatment / incineration may generate a range of unknown byproducts that could pose environmental problems. Due to the limited current knowledge regarding the fate of PFAS, there are concerns that PFAS incineration may release toxic gases (tetrafluoromethane, hexafluoroethane, difluorocarbons, etc.). (36,37) .

[0017] Thermal treatment, such as incineration, is a popular and effective technology for disposing of hazardous materials in land-scarce and resource-poor areas because it can significantly reduce waste volume and generate electricity. However, a major problem associated with waste incineration is the emission of harmful gases. Furans and fluorinated compounds are commonly studied gases due to their significant health hazards. Research on the production of perfluorinated compounds (PFCs) from thermal processing is limited. However, the thermal decomposition of PFASs has been reported to form environmentally harmful gaseous PFCs, such as CF4 and C2F6. Gaseous PFCs are potent greenhouse gases. CF4 has a global warming potential 6,500 times that of CO2, and C2F6 has an atmospheric lifetime of 50,000 years. Due to their long atmospheric lifetimes, gaseous PFC emissions could permanently alter the atmospheric radiation budget. Other methods for disposing of PFASs are being investigated, but fluorinated halogenated hydrocarbons (such as those found in PFASs) are extremely difficult to destroy due to the strength of their carbon-fluorine bonds. More sustainable methods for disposing of PFASs, particularly those contained in the “environmental medium,” remain needed. Summary of the Invention

[0018] One aspect of this disclosure provides a method for destroying and disposing of fluorinated materials, such as polyfluoroalkyl substances (PFAS). The method involves placing an environmental medium containing the fluorinated material in a batch reactor along with a hydroxide base and optionally a solvent system to form a suspension, and maintaining the fluorinated material in the batch reactor until defluorination waste is generated. The solvent system includes diethylene glycol dimethyl ether, polyether, polyether alcohol, any polyethylene glycol selected from ethylene glycol, PEG50 to PEG3350, N-methylpyrrolidine, dihydro-L-glucanone (cyrene), or water (“solvent”).

[0019] According to one exemplary embodiment, the environmental medium containing the fluorinated material is soil, granular activated carbon (GAC), biological solids, or other media found in the environment, and is referred to as the "environmental medium." According to this example, the batch reactor is located at the site of the "environmental medium." The batch reactor may be located in a mobile unit.

[0020] Fluorinated materials can be kept at room temperature in a batch reactor, or they can be heated in a batch reactor.

[0021] According to one exemplary embodiment, the fluorinated material, the hydroxide base, and the optional "solvent" are reacted with each other in a batch reactor for a period of about 0.5 hours to about 240 hours; and the heating step includes heating the suspension to a temperature ranging from about 25°C to about 400°C.

[0022] According to another exemplary embodiment, the hydroxide base is potassium hydroxide; the heating step includes heating to a temperature of about 180°C; the fluorinating material is PFAS; the PFAS, the hydroxide base and the "solvent" are placed in a batch reactor and allowed to react with each other for about 4 hours to about 8 hours.

[0023] The hydroxide base may include at least one of the following: potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), cesium hydroxide (CsOH), lithium hydroxide (LiOH), sodium hydroxide (NaOH), strontium hydroxide (Sr(OH)2), and mixtures thereof. The "solvent" may be added to the batch reactor and may include at least one of diethylene glycol dimethyl ether, polyethylene glycol ether, dihydro-L-glucanone, N-methylpyrrolidone, and deionized water.

[0024] Another aspect of this disclosure provides a method for destroying and disposing of fluorinated materials, which includes spraying a hydroxide base and optional "solvent" onto the fluorinated material (e.g., PFAS).

[0025] The fluorinated material is contained in an environmental medium. For example, the spraying step can be applied to an "environmental medium" containing the fluorinated material, and the spraying step can be performed at a site containing the "environmental medium." According to one embodiment, the method may include heating the fluorinated material after the spraying step.

[0026] Another aspect of this disclosure provides a batch reactor for treating fluorinated materials contained in environmental media according to the methods disclosed herein. The fluorinated material is PFAS. Attached Figure Description

[0027] Other advantages of the invention will be readily recognized as they become better understood by referring to the following detailed description taken in conjunction with the accompanying drawings, in which:

[0028] Figure 1 An intermittent system according to an exemplary embodiment is shown for destroying and defluorinating fluorocarbons present in PFAS (particularly in PFAS-contaminated "environmental media") to produce defluorinated waste products. Detailed Implementation

[0029] The materials, compounds, compositions, and methods described herein can be more readily understood by referring to the following detailed description of specific aspects of the disclosed subject matter and the examples contained therein.

[0030] Before disclosing and describing the materials, compounds, compositions, and methods of the present invention, it should be understood that the aspects described below are not limited to specific methods with specific reagents, as these can certainly vary. It should also be understood that the terminology used herein is for descriptive purposes only and is not intended to be limiting.

[0031] Furthermore, numerous publications are cited throughout this specification. The disclosures of these publications are incorporated herein by reference in order to provide a more comprehensive description of the prior art in the field to which the disclosed subject matter pertains. The disclosed references are also individually and specifically incorporated herein by reference for the material contained therein, which is discussed in the sentences upon which the references depend.

[0032] In this specification and the appended claims, several terms will be used, which should be defined to have the following meanings:

[0033] Throughout the specification and claims, the word “comprising” and other forms of the word mean, but are not intended to exclude, other additives, “solvents,” bases, components, integers, or steps. As used herein, nouns without quantifiers include singular or plural indicators unless the context clearly indicates otherwise. Thus, for example, reference to “composition” includes a mixture of two or more such compositions. “Optional” or “optionally” means that an event or condition subsequently described may or may not occur, and the description includes both the occurrence and non-occurrence of the event or condition. Although the wide range of numerical ranges and parameters illustrating the scope of this disclosure are approximate, the numerical values ​​illustrated in specific instances are reported as precisely as possible. However, any numerical value inherently includes some error unavoidably arising from the standard deviation present in their respective test measurements. Furthermore, when different ranges of numerical values ​​are illustrated herein, any combination of these values, including those listed, is contemplated for use. Additionally, ranges herein may be expressed as “about” a particular value and / or to “about” another particular value. When such a range is expressed, the other aspect includes from one particular value and / or to another particular value. Similarly, when a value is expressed as an approximation using the antecedent “about,” it should be understood that said particular value forms another aspect. It should also be understood that the endpoints of each range are significant both relative to and independent of the other endpoint. Unless otherwise stated, the term “about” means within 5% (e.g., within 2% or 1%) of the particular value modified by the term “about.”

[0034] It should be understood that throughout the specification, the identifiers “first” and “second” are used only to help distinguish the various components and steps of the disclosed subject matter. The identifiers “first” and “second” are not intended to imply any particular order, amount, preference, or importance of the components or steps modified by these terms. As used herein, the term “composition” is intended to cover products containing a specified amount of a specified ingredient, and any product produced directly or indirectly from a combination of specified amounts of the specified ingredients. References to parts by weight of a particular element or component in the specification and concluding claims indicate a weight relationship between that element or component and any other element or component in the composition or article, expressed in parts by weight. Thus, in a mixture containing 2 parts by weight of component X and 5 parts by weight of component Y, X and Y are present in a 2:5 weight ratio, and are present in such a ratio regardless of whether the mixture contains other components. Unless specifically stated to the contrary, the weight percentage (wt%) of a component is based on the total weight of the formulation or composition containing that component. As used herein, the term “substituted” is considered to include all permitted substituents of inorganic base compounds. In a broad sense, permitted substituents include all alkali metals and alkaline earth metals in the periodic table. Exemplary substituents include those described below, for example. For suitable inorganic base compounds, permitted substituents may be one or more, and may be the same or different.

[0035] Those skilled in the art will understand that compounds of Formula I are examples of inorganic base analogs. As used herein, “an analog of potassium hydroxide” or “analogs of potassiumhydroxide” is not limited to those analog compounds represented by Formula I, and may include numerous additions or substitutions of elements, groups, or portions of the chemical structure of potassium hydroxide.

[0036] M(OH)x

[0037] Formula I

[0038] Where x is the number of hydroxyl units per M valence; and

[0039] M is selected from the alkali metals or alkaline earth metals group.

[0040] Efforts have been made to ensure the accuracy of figures (e.g., quantities, temperatures, etc.), but some errors and deviations should be considered. Unless otherwise stated, parts are by weight, temperatures are in °C or ambient temperature, and pressures are at or near atmospheric pressure. Many variations and combinations of reaction conditions exist (e.g., component concentrations, temperatures, pressures, and other reaction ranges and conditions that can be used to optimize the purity and yield of the product obtained by the method). Such process conditions can be optimized with only reasonable and routine experiments.

[0041] The following examples illustrate methods and results based on the disclosed subject matter. These examples are not intended to encompass all aspects of the subject matter disclosed herein, but rather to illustrate representative methods and results. These examples are not intended to exclude equivalents and variations of the invention that will be apparent to those skilled in the art.

[0042] One aspect of the present invention provides systems and methods for disposing of perfluoroalkyl and polyfluoroalkyl substances (PFAS) while reducing emissions of gaseous PFCs such as CF4 and C2F6. In some embodiments, the PFAS is a single perfluorinated compound and a polyfluorinated compound, or a mixture of several perfluorinated compounds and polyfluorinated compounds. The invention also relates to methods for adding a "solvent" to the PFAS and applying several heating temperatures during the degradation process. More specifically, the subject matter disclosed herein relates to systems and methods that can be used to reduce emissions of gaseous perfluorinated compounds (PFCs) during the thermal treatment of PFAS.

[0043] Various types of PFAS, such as perfluorooctanoic acid (PFOA), can be treated using the intermittent system according to the invention. Although this system and method are generally applied to PFAS, and PFAS will be discussed throughout this disclosure, the system and method can be used to dispose of any type of fluorocarbon or fluorinated material. The system and method break carbon-fluorine bonds and convert organic fluorine present in fluorocarbons or other fluorinated materials into inorganic fluorides.

[0044] According to exemplary embodiments, the PFAS or other fluorinated materials disclosed herein are present in the environmental medium.

[0045] Methods for the destruction and disposal of fluorinated materials or environmental media containing fluorinated materials such as PFAS first involve introducing the PFAS-contaminated "environmental media" into a batch system, more specifically into a batch reactor. A hydroxide base, such as potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), cesium hydroxide (CsOH), lithium hydroxide (LiOH), strontium hydroxide (Sr(OH)2), and / or sodium hydroxide (NaOH), is then added. Optionally, a "solvent" is also added to the batch reactor to form sludge / suspension. Water may also optionally be present in the batch reactor as a co-solvent.

[0046] PFAS-contaminated media are typically maintained in batch reactors at temperatures in the range of room temperature for several days, or at 100°C and 200°C for at least 2 hours, for example, 3 to 5 hours, or up to 8 hours, to defluorinate the PFAS-contaminated "environmental media" and produce defluorination waste products consisting of inorganic fluorides. Some types of PFAS, such as perfluorooctyl sulfonate (PFOS), may require higher temperatures and longer times in the reactor, such as temperatures up to, but not limited to, 300°C. According to other embodiments, the temperature of the batch system can be below 100°C, for example, room temperature or 50°C up to 100°C. When the temperature of the batch system is lower, the time required to defluorinate the PFAS in the contaminated "environmental media" and produce defluorination waste products consisting of inorganic fluorides is longer. The resulting defluorination waste typically includes polyethylene glycol and / or "solvents" used in the reactor, formates, carbonates, oxalates and / or glycolates, organic salts, and inorganic fluorides. The composition of the inorganic fluorides (i.e., potassium fluoride, sodium fluoride, lithium fluoride, strontium fluoride and / or calcium fluoride, or combinations thereof) depends on the base hydroxide or mixtures of base hydroxides used in the batch system. The defluorination waste can be further incinerated without significant emissions of harmful gaseous PFCs.

[0047] Figure 1 A batch system and method according to an exemplary embodiment are shown. According to this example, an "environmental medium" containing PFAS is fed into a batch reactor along with PEG and potassium hydroxide (KOH). The PEG is PEG200 with a molar mass of 190 g / mol to 210 g / mol and the chemical formula H-(O-CH2CH2). n -OH, where n = 8.2 to 9.1. PEG200 can optionally be replaced with diethylene glycol dimethyl ether, polyether, polyether alcohol, N-methylpyrrolidone, dihydro-L-glucanone, water, and / or polyethylene glycol selected from ethylene glycol and / or PEG50 to PEG3350. KOH can be replaced with other hydroxide bases including, but not limited to, sodium, calcium, lithium, strontium, or cesium, or optionally mixtures thereof. According to this example, the PFAS-contaminated “environmental medium” is reacted in an intermittent system at ambient pressure and a temperature of 180°C to 200°C for approximately 4 hours. The resulting defluorination waste products include potassium fluoride (KF) generated from the product, PEG200, unreacted excess potassium hydroxide (KOH), and organic salts of carbonates and / or formates and / or oxalates and / or glycolates, or mixtures thereof. Figure 1 The chemical reactions that occur in exemplary batch systems include:

[0048]

[0049] Following the intermittent process, the defluorination waste products can be thermally treated, for example, by incineration, while reducing the emissions of harmful gaseous PFCs such as CF4 and C2F6.

[0050] Prior to incineration, some components present in the defluorination waste can be recovered or removed and disposed of without thermal treatment. For example, according to one embodiment, PEG200 is removed from the defluorination waste and recovered. The recovered PEG200 can be used in future batch systems.

[0051] Another aspect of the invention is the ability to reuse unreacted components during the defluorination process of PFAS-contaminated "environmental media".

[0052] As described above, the system and method for treating, destroying and disposing of perfluoroalkyl substances and polyfluoroalkyl substances (PFAS) while reducing gaseous PFC emissions can be applied to "environmental media" containing PFAS.

[0053] According to one embodiment, the treatment of PFAS-contaminated "environmental media" is carried out at the location of the PFAS-contaminated "environmental media" ("in situ") using the systems and methods described herein. For example, the treatment can be carried out at the site of the generator. A mobile unit comprising a batch reactor is located at the site of the "environmental media" or is brought to the site of the "environmental media". As described above, the PFAS-containing "environmental media", along with a hydroxide base (strong base) and optionally a "solvent", is added to the batch reactor. The PFAS-containing "environmental media", the hydroxide base, and optionally the "solvent" are maintained in the batch reactor at temperatures in the range of room temperature for several days, or at 100°C and 200°C for at least 2 hours, for example, 3 to 5 hours, or up to 8 hours, to defluorinate the PFAS and produce defluorinated waste consisting of inorganic fluorides.

[0054] According to another embodiment, in-situ treatment is performed by spraying a base hydroxide and optional "solvent" directly onto the PFAS-containing "environmental medium." For example, spraying can be applied to contaminated "environmental medium" still on the ground. After the spraying step, if necessary, the contaminated "environmental medium" can be covered, and the base hydroxide and optional "solvent" can be left on the contaminated "environmental medium" for several weeks. If desired, the contaminated "environmental medium" can also be heated after the treatment step. After several weeks, the "environmental medium" is tested to determine if an appropriate (reduced) PFAS level has been achieved. If the desired level has not been achieved, more base hydroxide and optional "solvent" can be added until an appropriate level is achieved.

[0055] The in-situ treatment of the aforementioned contaminated “environmental media” offers several advantages, primarily reducing time and costs, as the contaminated “environmental media” does not need to be transported to off-site facilities.

[0056] experiment

[0057] The general procedure for defluorination reaction.

[0058] PFAS-contaminated "environmental media" were treated with a hydroxide base (sodium hydroxide, potassium hydroxide, or calcium hydroxide, or combinations thereof, in different ratios) for 4 hours at 150°C to 200°C, either without additives or in the presence of "solvents" in varying ratios. The resulting reaction mixture was then cooled to room temperature. The reaction material was analyzed by 19F NMR.

[0059] Representative Example 1. "Solvent" assisted.

[0060] In a 40 mL screw-capped vial, a solution of AFFF (750 ppm PFAS) in DIW:polyethylene glycol 200 (1:1) was added to Gainesville land soil (14.59 g / 1 part), followed by the addition of crushed potassium hydroxide granules (1.44 g / 10% wt). The vial was immersed in a 70°C oven and allowed to react for 8 hours. The resulting suspension in the amber-colored reaction liquid was cooled to room temperature, sonicated for 15 minutes, then centrifuged at 3000 rpm for 15 minutes and decanted. 19 F NMR analysis of the precipitate showed that the reaction solution contained only inorganic potassium fluoride.

[0061] In summary, in one aspect, according to the purpose of the disclosed materials and methods, as embodied and broadly described herein, the disclosed subject matter relates to compositions and methods for defluorinating or destroying PFAS-contaminated "environmental media" to produce inorganic fluorides in salt form. Furthermore, the invention relates to methods for reducing gaseous perfluorinated compound (PFC) emissions during the heat treatment of PFAS-contaminated "environmental media." In a specific aspect, the disclosed subject matter relates to the selection of materials for greener processes.

[0062] Some embodiments of the present invention provide compositions comprising at least one "solvent" and a strong base; and wherein, according to reaction scheme I, the hydroxide base comprises potassium hydroxide, sodium hydroxide, cesium hydroxide, lithium hydroxide, strontium hydroxide and / or calcium hydroxide, or combinations thereof, in weight / weight% of their respective compositions.

[0063]

[0064] in:

[0065] n is the minimum amount of molar equivalent used to degrade organofluorine in PFAS;

[0066] M includes potassium, sodium, cesium, lithium, strontium, or calcium;

[0067] q represents the maximum amount of molar equivalents produced by the degradation of organic fluorine in the "environmental medium" contaminated by PFAS.

[0068] x represents the number of hydroxyl and fluorine units per M valence; and,

[0069] Y includes "solvent".

[0070] In another embodiment, according to reaction scheme II, these compositions as described above do not include the addition of the solvent.

[0071]

[0072] in:

[0073] n is the minimum amount of organic fluorine in the "environmental medium" used to degrade PFAS pollution;

[0074] M includes potassium, sodium, cesium, lithium, strontium, or calcium;

[0075] q represents the maximum amount of molar equivalents produced by the degradation of organic fluorine compounds in PFAS-contaminated "environmental media"; and,

[0076] x represents the number of hydroxyl and fluorine units per M valence.

[0077] Clearly, based on the above teachings, many modifications and variations of the invention are possible and can be implemented in ways different from those specifically described within the scope of the following disclosure and claims.

[0078] References

[0079]

[0080]

[0081]

[0082]

[0083] Those skilled in the art will understand that modifications can be made to the embodiments of the invention described herein without departing from the broad inventive concept of the invention. Therefore, it should be understood that the invention is not limited to any particular embodiment disclosed, but is intended to cover modifications within the spirit and scope of the invention as defined by the appended claims.

Claims

1. A method for destroying and disposing of fluorinated materials, comprising the following steps: An environmental medium containing fluorinated material is placed in a batch reactor along with a hydroxide base and optional solvent to form a suspension, and the fluorinated material is held in the batch reactor until defluorination waste is generated. The solvent includes diethylene glycol dimethyl ether, polyether, polyether alcohol, N-methylpyrrolidone, dihydrol-glucosinolate, water, and / or polyethylene glycol selected from one or more of PEG50 to PEG3350 and / or ethylene glycol.

2. The method according to claim 1, wherein the fluorinated material is any polyfluoroalkyl substance (PFAS).

3. The method according to claim 1, wherein the environmental medium containing the fluorinated material is soil.

4. The method of claim 3, wherein the intermittent reactor is located at the site of the soil.

5. The method according to claim 1, wherein the environmental medium containing the fluorinated material is GAC.

6. The method of claim 5, wherein the batch reactor is located at the site of the GAC.

7. The method according to claim 1, wherein the environmental medium containing the fluorinated material is a biological solid.

8. The method of claim 7, wherein the intermittent reactor is located at the site of the biosolid.

9. The method of claim 4, wherein the intermittent reactor is located in a mobile unit.

10. The method of claim 6, wherein the intermittent reactor is located in a mobile unit.

11. The method of claim 8, wherein the intermittent reactor is located in a mobile unit.

12. The method of claim 1, wherein the fluorinated material is maintained at room temperature in the batch reactor.

13. The method of claim 1, wherein the fluorinated material is heated in the batch reactor.

14. The method of claim 13, wherein the fluorinated material, the hydroxide base, and optionally the solvent are reacted with each other in the batch reactor for a period of about 0.5 hours to about 240 hours; and the heating step comprises heating the suspension to a temperature ranging from about 25°C to about 400°C.

15. The method of claim 13, wherein the hydroxide base is potassium hydroxide; the heating step includes heating to a temperature of about 180°C; the fluorinating material is PFAS; and the PFAS, the hydroxide base, and the solvent are placed in the batch reactor and allowed to react with each other for about 4 hours to about 8 hours.

16. The method according to claim 1, wherein the hydroxide base comprises at least one of the following: potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), cesium hydroxide (CsOH), lithium hydroxide (LiOH), sodium hydroxide (NaOH), strontium hydroxide (Sr(OH)2), and mixtures thereof.

17. The method of claim 1, wherein the solvent comprising polyether, polyether alcohol, any polyethylene glycol selected from, diethylene glycol dimethyl ether, polyether, polyether alcohol, N-methylpyrrolidine, dihydrol-L-glucanone, water and / or polyethylene glycol selected from one or more of PEG50 to PEG3350 and / or ethylene glycol is added to the batch reactor, and comprises at least one of polyethylene glycol selected from ethylene glycol, diethylene glycol dimethyl ether and / or polyethylene glycol selected from PEG50 to PEG3350.

18. The method of claim 17, wherein the preferred solvent is PEG200.

19. A method for destroying and disposing of fluorinated materials, comprising spraying a hydroxide base and optionally a solvent onto the fluorinated material.

20. The method of claim 19, wherein the fluorinated material is PFAS.

21. The method of claim 19, wherein the spraying step is applied to an environmental medium containing the fluorinated material.

22. The method according to claim 21, wherein the environmental medium is soil.

23. The method of claim 16, wherein the spraying step is performed at the site of the soil.

24. The method of claim 21, wherein the environmental medium is GAC.

25. The method of claim 16, wherein the environmental medium is GAC.

26. The method of claim 21, wherein the environmental medium is a biological solid.

27. The method of claim 16, wherein the environmental medium is a biological solid.

28. The method of claim 19, further comprising heating the fluorinated material after the spraying step.

29. A system comprising a batch reactor for disposing of fluorinated materials according to the method of claim 1.

30. The system of claim 29, wherein the environmental medium is soil.

31. The system of claim 29, wherein the environmental medium is GAC.

32. The system according to claim 9, wherein the environmental medium is a biological solid.

33. The system of claim 29, wherein the fluorinated material is any perfluoroalkyl substance and polyfluoroalkyl substance (PFAS).

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