Method and apparatus for destruction and defluorination of perfluoroand polyfluoroalkyl materials (pfas), fluorotelomers and other persistent organic contaminants

Abstract

A process for disrupting PFAS comprising irradiating a solution comprising one or more PFAS with UV radiation, the solution further comprising one or more photosensitizers (preferably sodium iodide or potassium iodide), one or more bases that bring the pH of the solution greater than 13, and sulfite ions. The present disclosure also describes processes using a combination of oxidative and reductive disruption for disrupting persistent and stubborn organic contaminants containing PFAS. The present disclosure also describes a treatment system that uses a UV oxidation process followed by a UV reduction process on the product of the UV oxidation process.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of Provisional Application No. 63 / 353,879, filed on June 21, 2022, entitled “Methods and Apparatus for the Destruction and Defluorination of Per- and Polyfluoroalkyl Substances (PFAS), Fluorotelomers, and Other Persistent Organic Pollutants,” the entire contents of which are incorporated herein by reference.

[0003] background

[0004] Per- and polyfluoroalkyl substances (PFASs) are a class of synthetically prepared compounds that have been used for decades in many consumer and industrial applications. PFASs have some unique surface properties and can be both hydrophobic and oleophobic. As a result, PFASs are used as coating aids, lubricants, foaming aids, and in various surface treatments. They have proven to be particularly useful as flame retardants in the form of aqueous film-forming foams (AFFF). In addition, some PFAS are known to bioaccumulate in plants and animals. There is growing evidence that exposure to PFAS can also lead to various health problems. Due to these concerns, regulatory agencies around the world have begun to establish strict limits on the presence of PFAS in food and water.

[0005] PFASs are a class of chemicals that contain per- or polyfluoroalkyl groups. The definition and classification of per- and polyfluoroalkyl substances (PFASs) have changed over time. The definition used here is the 2021 definition from the Organization for Economic Co-operation and Development (OECD), which expanded their terminology to state that "PFASs are defined as fluorinated substances containing at least one fully fluorinated methyl or methylene carbon atom (without any H / Cl / Br / I atoms attached to it), i.e., with few exceptions, any chemical with at least one perfluoromethyl (–CF3) or perfluoromethylene (–CF2–) group is a PFAS." Some of the most important examples of PFASs include perfluorosulfonic acids (e.g., perfluorooctane sulfone (PFOS)) and perfluorocarboxylic acids (PFCAs) (e.g., perfluorooctane carboxylic acid (PFOA)). Fluorotelomers are fluorocarbon-based oligomers or telomers synthesized by telomerization. Some fluorotelomers and fluorotelomer-based compounds are sources of environmentally persistent perfluorocarboxylic acids (e.g., PFOA).

[0006] The continued presence of PFASs, health concerns, and the regulatory environment have prompted a large amount of research efforts to reduce their presence in the environment. Much of the early work focused on capture, such as from drinking water. However, more recently there has been a greater effort to destroy these materials. One property of PFASs is their resistance to breakdown in the environment. PFAS are not easily metabolized by organisms and are not broken down by exposure to visible light or longer wavelength UV radiation, which is common in terrestrial conditions.

[0007] The two main modes of chemically mediated PFAS destruction are oxidation and reduction. Oxidative destruction refers to the removal of electrons from the target species (i.e., PFAS) followed by degradation, while reductive destruction refers to the addition of electrons to the target species followed by degradation. Oxidative and reductive destruction of PFAS can be achieved with a variety of reagents (e.g., persulfates, hydrogen peroxide, nitrates, and other reagents for oxidation reactions; or iodides, sulfites, and other reagents for reduction reactions) and input energy (e.g., ultraviolet light or ultrasound treatment, etc.). Due to the huge structural diversity of PFAS as a class, individual target PFAS have varying degrees of sensitivity to oxidative or reductive destruction mechanisms, and the number of sequential oxidation / reduction destruction processes reported in the past is limited. Therefore, a "one-pot" approach is needed that involves the use of ultraviolet light or ultrasound treatment as an energy initiation source. SUMMARY OF THE INVENTION

[0009] The present disclosure contains embodiments directed to and containing a device for destroying PFAS, which device contains a reaction chamber including one or more UV radiation sources, one or more ports for adding oxidizing species or one or more reducing species, and one or more sensors for measuring one of the following: pH, oxidation or reduction potential of the solution (ORP sensor), fluoride concentration, UV intensity, conductivity, temperature and pressure.

[0010] The present disclosure also contains embodiments directed to and containing processes for destroying PFASs, comprising irradiating a solution containing one or more PFASs with UV radiation, the solution comprising the following components: one or more sensitizers capable of absorbing UV radiation, one or more bases having a pH greater than 13, and sulfite ions.

[0011] The present disclosure also contains embodiments directed to and containing processes for destroying ultra-short-chain PFASs, comprising irradiating a solution containing one or more ultra-short-chain PFASs with UV radiation, wherein the solution includes: one or more sensitizers capable of absorbing UV radiation, one or more bases such that the pH of the solution is greater than 13, and sulfite ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The following drawings are illustrative of embodiments and do not limit the scope of the invention. The drawings are not necessarily to scale and are intended to be used in conjunction with the following detailed description. Embodiments of the invention will be described with reference to the accompanying drawings, in which like numbers may represent like elements.

[0013] Figure 1 is a graph showing reductive destruction of a pre-oxidized PFAS stock solution according to some embodiments of the present disclosure;

[0014] Figure 2is a block diagram showing steps of an inventive process according to some embodiments of the present disclosure;

[0015] Figure 3 is a cross-sectional view of a batch or continuous reactor for use with some embodiments of the present disclosure.

[0016] Detailed Summary of the Invention

[0017] As used herein, the term "destruction" refers to the breakdown of toxic chemicals or organic pollutants into harmless by-products.

[0018] As used herein, the term "defluorination" refers to the breaking of CF bonds in CF-based chemical compounds such as PFAS or fluorotelomers.

[0019] Ultra-short-chain PFAS can be any perfluorinated or polyfluorinated molecule with a chain length of three carbon atoms or less.

[0020] Reductive destruction methods have been shown to be excellent for treating perfluorocarboxylic acids and perfluorosulfonic acids such as PFOA, PFOS and their short-chain analogs, as well as perfluoroethers such as HFPO-DA. However, reduction reactions are not effective for treating fluorotelomer compounds such as 6:2FTS.

[0021] In contrast, oxidative destruction methods have demonstrated significant efficacy in the degradation of fluorotelomers such as 6:2FTS, producing short-chain perfluorocarboxylate and perfluorosulfonate PFAS as degradation byproducts, but the oxidation reaction lacks the ability to destroy the short-chain perfluorocarboxylate and perfluorosulfonate compound byproducts it produces.

[0022] The structures of representative PFAS are shown below.

[0023] Chemical structures of PFOA, PFOS, 6:2 FTS, and HFPO-DA

[0024]

[0025] This difference in effectiveness between reductive and oxidative treatments is illustrated below in Figures 1 and 2, which show the destruction of the same aqueous film forming foam (AFFF) contaminated waste stream. Figure 1 shows the reductive case, demonstrating over 95% destruction of two perfluorocarboxylate compounds in the substrate, PFPeA and PFHxA, but no destruction of the major 6:2 FTS fluorotelomer compound.

[0026] Figure 1

[0027] Reductive destruction of PFAS:

[0028]

[0029] In contrast, the oxidative case (shown in Figure 2 below) destroyed over 90% of the initial 6:2FTS fluorotelomer, but left behind a large increase in byproduct short-chain carboxylates PFBA, PFPeA, PFHxA, and PFHpA due to the degradation of 6:2FTS and other undetected pre-oxidized PFAS compounds in the matrix.

[0030] Figure 2

[0031] Oxidative destruction of PFAS:

[0032]

[0033] Embodiments of the present disclosure improve the destruction of PFAS and its byproducts compared to each of the above-mentioned approaches. For example, according to the present disclosure, in some embodiments, complete destruction can be achieved by combining the above-mentioned oxidative and reductive methods in sequence, first oxidizing the target substrate (as shown in Figure 2) and then reducing it (as shown in Figure 1).

[0034] like Figure 1 As can be seen, the efficacy of the reductive treatment according to embodiments of this combined, disclosed method on a stock solution of PFAS that has been oxidized from its original form has been demonstrated to be able to destroy a minimum of 90% and a maximum of 99.99% of the remaining PFAS in the solution after pre-oxidation.

[0035] According to some embodiments of the present disclosure, PFAS-affected substrates (e.g., AFFF-contaminated wastewater) can be subjected to oxidation treatment to degrade oxidation-sensitive compounds (e.g., 6:2FTS and other fluorotelomers) into shorter chain carboxylates or sulfonates that are difficult to oxidatively treat. After the oxidation process, the wastewater can be subjected to reduction treatment to destroy the remaining carboxylate and sulfonate compounds. This combined treatment according to embodiments of the present disclosure can effectively eliminate all PFAS in the substrate, thereby achieving safe disposal.

[0036] Example 1

[0037] Contaminated military wastewater was subjected to a five-liter scale one-pot sequential oxidation-reduction process on aqueous film forming foam (AFFF) (Figure 3 below) that replicated the separate experiments shown above in Figures 1 and 2. The time series showed the same trend of increase in short-chain carboxylate compounds as 6:2FTS and other PFAS components degraded oxidatively, followed by rapid destruction of carboxylate compounds when the process switched to reduction mode.

[0038] Figure 3

[0039] Sequential Oxidation-Reduction of AFFF-Contaminated Military Wastewater in a 5-L Reactor:

[0040]

[0041] According to some embodiments of the present disclosure, PFAS-contaminated wastewater can be treated in the following manner, although it should be understood that the embodiments of the present disclosure are not limited to the following: First, an oxidizing agent containing but not limited to hydrogen peroxide, sodium persulfate, metal nitrates (zinc nitrate, nickel nitrate, etc.), or titanium dioxide or other metal, metal oxide or non-metallic nanoparticles (nanoparticle size range between about 1-500nm) can be added to the PFAS wastewater at a concentration between about 0.001ppt-100,000ppm. Next, a base can be added to the reaction mixture, containing but not limited to hydroxide salts (e.g., sodium hydroxide, calcium hydroxide, ammonium hydroxide, etc.) and carbonates and bicarbonates (e.g., sodium bicarbonate). The concentration of the added base reagent can range from about 50mM to about 1M.

[0042] Notably, the addition of the base can be performed before, during or after the oxidation treatment. The concentration of the oxidizing agent can range between about 0.1 mM and about 100 mM; in some embodiments, preferably between 2-10 mM. In some embodiments, the sample can be irradiated with light having a wavelength of about 100 nm to about 500 nm, in some embodiments, preferably about 180 to about 300 nm, for a time range of about 10 minutes to about 96 hours, in some embodiments, preferably about 40 min to about 240 min.

[0043] After this oxidation reaction, in some embodiments, the oxidizing agent may be quenched or removed from the solution. A reducing agent containing, but not limited to, sodium sulfite, potassium iodide, indole derivatives, and other hydrated electron generating organic or inorganic agents or catalysts may then be added to the reaction mixture and irradiated with light having a wavelength between about 150 nm and about 500 nm, preferably between about 200 and about 300 nm in some embodiments, for a time range of about 10 minutes to about 96 hours, preferably about 1 to about 4 hours in some embodiments, destroying more than 92% of all remaining PFAS degradation byproducts of the oxidation reaction according to some embodiments. In some embodiments, the concentration range of the reducing agent may be between about 0.1 mM and about 200 mM, preferably between about 2 and about 50 mM in some embodiments.

[0044] In some embodiments, for example, the addition of reagents can be performed in batches at the initialization of the program or throughout the reduction process. For example, in water significantly affected by common contaminants (such as nitrates, organic components, or cationic metal species), higher reagent addition amounts (such as, but not limited to, about 200 mM) can be used. This post-treatment substrate with PFAS removed can then be safely disposed of.

[0045] Figure 4 (below) shows the reductive destruction and defluorination of a PFAS-impacted industrial waste stream containing ultra-short chain PFAS according to an embodiment of the present disclosure. An ultra-short chain PFAS can be any perfluorinated or polyfluorinated molecule with a chain length less than or equal to three carbon atoms. As shown, the above reduction procedure ultimately reduced the total organic fluorine (TOF) observed in the PFAS-impacted industrial waste sample by a significant and impressive 96% from an initial TOF concentration of 33,114 ppb (μg / L).

[0046] Figure 4

[0047] Identification of Per- and Polyfluoroalkyl Substances in PFAS-Impacted Industrial Waste Streams Treated by Claros Technology Reductive destruction and defluorination

[0048]

[0049] Table 1 provides the results obtained from treating AFFF wastewater from a military base using a 5-liter reactor according to Example 1. As can be seen, 2-4 hours of treatment resulted in 92-100% destruction of all PFAS compounds in one go.

[0050] Table 1

[0051] PFAS compounds Initial concentration Final concentration Destruction percentage <![CDATA[6:2 FtTA 0 S]]> -3000ppb N / D 100％ 6:2 FTS 638ppb 50ppb 92％ PFBA 369ppb 27ppb 93％ PFA 1350ppb 51ppb 96％ PFh 3967ppb 124ppb 97％ PFHpA 368ppb 15ppb 96％

[0052] Figure 2 The main steps involved in a combined oxidative-reductive treatment according to some embodiments of the present invention are shown. Figure 3 An example of a batch or continuous reactor that can be used for sequential UV oxidative-reductive treatment of PFAS contaminated streams (water, wastewater, AFFF) according to some embodiments of the present invention is shown. Figure 3 The system is performed in a batch or continuous reactor as shown. The system contains an opaque reactor tank or container (1) made of or other materials; one or more UV lamps (2) emitting wavelengths in the range of about 100-about 500 nm; an optional pH sensor (3); and a stirring system (4), including but not limited to an impeller, mixer and / or agitator for homogenizing solutions or reagents. In addition, the system can have an inlet (A) for a PFAS concentrated solution or a PFAS-contaminated stream; an effluent (B); an oxidizing agent inlet (C); a reducing agent inlet (D); and an acid / base inlet (E) for pH control. It should be understood that the positioning of the system components may be different from that shown.

[0053] The inventive process disclosed herein can also be applied to other persistent organic pollutants, for example, including but not limited to: aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene, mirex, polychlorinated biphenyls, polychlorinated dibenzo-p-diphenylamines, polychlorinated dibenzofurans and toxaphene.

[0054] Similarly, the inventive processes disclosed herein can be applied to other stubborn water pollutants, such as, but not limited to, 3,4,3'4'-tetrachlorobiphenyl 2,4,5,2'4,5'-hexachlorobiphenyl, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT), 1,C,3,4,5,6-hexachlorocyclohexane (lindane) and benzo[a]pyrene, chlordane, 2,2,2-trichloro-1,1-bis(4-chlorophenyl)ethanol (dicofol), pentachlorophenol, Aroclor-1254, phenanthrene, biphenyl-p-cresol and 2-methylnaphthalene.

[0055] Embodiments of the present disclosure provide many advantages. As described herein, some embodiments of the present disclosure may use a UV-based oxidation reaction followed by a UV-based reduction reaction. Thus, these embodiments use UV in both steps and can be performed at near ambient temperature (no heat is applied other than the heat generated by the UV lamp). The result is a very high destruction rate of up to 100% for fluorotelomers, and a destruction rate of 92-97% for other PFAS. It also allows both steps of the process to be performed in a single reactor because both steps are based on UV photochemistry. In addition, embodiments of the present disclosure may only require the input of reagents twice; (1) at the beginning of the oxidation reaction and (2) then at the beginning of the reduction reaction, and can be performed without continuous introduction of reagents in the process. In addition, the process can be performed quickly, for example in about 1-4 hours or less. Finally, by avoiding the high temperatures required by the use of prior art thermal oxidation processes, the process requires less energy input.

[0056] Embodiments of the present disclosure may also include a device for destroying PFASs, comprising the following elements: 1) a reaction chamber containing one or more UV radiation sources, 2) one or more ports for adding oxidizing species or one or more reducing species, 3) optionally, equipped with one or more sensors capable of measuring one of the following: pH, oxidation or reduction potential of the solution (ORP sensor), fluoride concentration, UV intensity, conductivity, temperature and pressure; 4) optionally, a thermal jacket surrounding at least a portion of the reaction chamber, which can be cooled or heated with a fluid.

[0057] Embodiments of the present disclosure may also include an apparatus for destroying PFASs comprising a thermal jacket surrounding at least a portion of a reactor.

[0058] Embodiments of the present disclosure may also include a device for destroying PFASs, which is equipped with one or more sensors capable of measuring one or more of the following: pH, oxidation or reduction potential of the solution (ORP sensor), fluoride concentration, UV intensity, conductivity, temperature and pressure.

[0059] Embodiments of the present disclosure may also include a device for destroying PFASs, which is equipped with one or more sensors capable of measuring one or more of the following: pH, oxidation or reduction potential of the solution (ORP sensor), fluoride concentration, UV intensity, conductivity, temperature and pressure; and a thermal jacket surrounding at least a portion of the reactor.

[0060] Embodiments of the present disclosure may also include an apparatus for destroying PFASs whereby the UV radiation source is one or more low-pressure mercury lamps.

[0061] Embodiments of the present disclosure may also contain a device comprising one or more sensors capable of measuring all of the following: pH, oxidation or reduction potential of the solution (ORP sensor), fluoride concentration, UV intensity, conductivity, temperature, and pressure.

[0062] Embodiments of the present disclosure may also include a process for destroying PFASs, which comprises irradiating a solution containing one or more PFASs with UV radiation, wherein the solution contains the following components: 1) one or more sensitizers capable of absorbing UV radiation; 2) one or more strong bases so that the pH of the solution is >13; and / or 3) optionally, sulfite ions.

[0063] Embodiments of the present disclosure may also include a process for destroying PFASs, which consists of irradiating a solution containing one or more PFASs with UV radiation, the solution containing sulfite ions.

[0064] Embodiments of the present disclosure may also contain solutions for destroying PFASs, wherein the one or more strong bases are alkali metal hydroxides such that the pH of the solution is >13.

[0065] Embodiments of the present disclosure may also include a process for destroying PFASs, wherein the one or more strong bases are sodium hydroxide, such that the pH of the solution is >13.

[0066] Embodiments of the present disclosure may also include a process for destroying PFASs, wherein the one or more strong bases are potassium hydroxide, such that the pH of the solution is >13.

[0067] Embodiments of the present disclosure may also include a process for destroying PFASs consisting of irradiating a solution containing sulfite ions, wherein the sulfite species is a sodium salt of sulfite.

[0068] Embodiments of the present disclosure may also include a process for destroying PFASs consisting of irradiating a solution containing sulfite ions, wherein the sulfite species is a potassium salt of sulfite.

[0069] Embodiments of the present disclosure may also include a process for destroying PFASs, wherein the one or more strong bases are a mixture of sodium hydroxide and sodium carbonate such that the pH of the solution is >13.

[0070] Embodiments of the present disclosure may also include a process wherein the sensitizer capable of absorbing UV radiation is sodium iodide or potassium iodide.

[0071] Embodiments of the present disclosure may also include a process in which one or more strong bases are added to make the pH of the solution > 13.2.

[0072] Embodiments of the present disclosure may also include a process for destroying PFASs consisting of irradiating a solution containing sulfite ions at a concentration of 5 mM to 500 mM sodium iodide and 50 mM to 1 M sodium sulfite.

[0073] Embodiments of the present disclosure may also include a process wherein the concentration of the sensitizer capable of absorbing UV radiation is 5 mM to 500 mM.

[0074] Embodiments of the present disclosure may also include a process for destroying ultra-short-chain PFASs, which process consists of irradiating a solution containing one or more PFAS with UV radiation, wherein the solution contains the following components: 1) one or more sensitizers capable of absorbing UV radiation; 2) one or more strong bases so that the pH of the solution is >13; and / or 3) optionally, sulfite ions.

[0075] Embodiments of the present disclosure may also include a process for destroying PFASs consisting of irradiating a solution containing one or more PFAS with UV radiation, the solution containing sulfite ions.

[0076] Embodiments of the present disclosure may also include a process for destroying PFASs, wherein the one or more strong bases are alkali metal hydroxides such that the pH of the solution is >13.

[0077] Embodiments of the present disclosure may also include a process for destroying PFASs, wherein the one or more strong bases are sodium hydroxide, such that the pH of the solution is >13.

[0078] Embodiments of the present disclosure may also include a process for destroying PFASs, wherein the one or more strong bases are potassium hydroxide, such that the pH of the solution is >13.

[0079] Embodiments of the present disclosure may also include a process for destroying PFASs consisting of irradiating a solution containing sulfite ions, wherein the sulfite species is a sodium salt of sulfite.

[0080] Embodiments of the present disclosure may also include a process for destroying PFASs consisting of irradiating a solution containing sulfite ions, wherein the sulfite species is a potassium salt of sulfite.

[0081] Embodiments of the present disclosure may also include a process for destroying PFASs, wherein the one or more strong bases are a mixture of sodium hydroxide and sodium carbonate such that the pH of the solution is >13.

[0082] Embodiments of the present disclosure may also include a process wherein the sensitizer capable of absorbing UV radiation is sodium iodide or potassium iodide.

[0083] Embodiments of the present disclosure may also include a process in which one or more strong bases are added to make the pH of the solution > 13.2.

[0084] Embodiments of the present disclosure may also include a process for destroying PFASs consisting of irradiating a solution containing sulfite ions at a concentration of 5 mM to 500 mM sodium iodide and 50 mM to 1 M sodium sulfite.

[0085] Embodiments of the present disclosure may also include a process wherein the concentration of the sensitizer capable of absorbing UV radiation is 5 mM to 500 mM.

[0086] Embodiments of the present disclosure may also include a process wherein the PFASs to be destroyed contain trifluoroacetic acid (TFA), perfluoropropionic acid (PFPrA), perfluoro-2-methoxypropionic acid (PMPA), or their conjugate bases.

[0087] Embodiments of the present disclosure may also contain a process for the destruction and defluorination of PFAS in water streams (wastewater, runoff water, AFFF, PFAS concentrates generated by water treatment systems) that includes using a UV oxidation process on the PFAS to produce a product and then using a UV reduction process on the product of the UV oxidation process.

[0088] Embodiments of the present disclosure may also contain a process for the destruction of persistent and recalcitrant organic contaminants other than PFAS in water streams (wastewater, runoff water, AFFF, PFAS concentrates generated by water treatment systems) comprising using a UV oxidation process on the contaminant to produce a product and then using a UV reduction process on the product of the UV oxidation process.

[0089] It should be understood that the disclosure is not limited to the particular embodiments disclosed, but encompasses all combinations of the various elements disclosed and any known or later-occurring variations thereof.

Claims

1. A device for destroying PFASs, comprising: a reaction chamber containing one or more UV radiation sources; one or more ports for adding an oxidizing species or one or more reducing species; as well as One or more sensors for measuring one of the following: pH, oxidation or reduction potential of the solution (ORP sensor), fluoride concentration, UV intensity, conductivity, temperature and pressure.

2. The apparatus of claim 1, further comprising a thermal jacket surrounding at least a portion of the reaction chamber, wherein the thermal jacket can be filled with a heating or cooling fluid.

3. The apparatus of claim 1, wherein at least one of said UV radiation sources is a low pressure mercury lamp.

4. A process for destroying PFASs, comprising: A solution containing one or more PFASs is irradiated with UV radiation, wherein the solution comprises the following components: one or more sensitizers capable of absorbing UV radiation, one or more bases having a pH greater than 13, and sulfite ions.

5. The process of claim 4, wherein the solution contains the sulfite ions.

6. The process of claim 4, wherein the base is an alkali metal hydroxide.

7. The process of claim 4, wherein the base is potassium hydroxide.

8. The process of claim 5, wherein the sulfite species is the sodium salt of sulfite.

9. The process of claim 5, wherein the sulfite species is a potassium salt of sulfite.

10. The process of claim 4, wherein the base comprises a mixture of sodium hydroxide and sodium carbonate.

11. The process of claim 4, wherein the sensitizer capable of absorbing UV radiation is sodium iodide or potassium iodide.

12. The process of claim 4, wherein the base is added in an amount sufficient to bring the pH of the solution to greater than 13.

2.

13. A process for destroying ultra-short chain PFASs, comprising: A solution containing one or more ultra-short chain PFASs is irradiated with UV radiation, wherein the solution includes: one or more sensitizers capable of absorbing UV radiation, one or more bases such that the pH of the solution is greater than 13, and sulfite ions.

14. The process according to claim 13, wherein the PFASs to be destroyed contain trifluoroacetic acid (TFA), perfluoropropionic acid (PFPrA), perfluoro-2-methoxypropionic acid (PMPA) or their conjugate bases.

15. The process of claim 13, wherein the one or more bases are alkali metal hydroxides.

16. The process of claim 13, wherein the one or more bases is potassium hydroxide.

17. The process of claim 13, wherein the sulfite ionic species is a sodium salt of sulfite.

18. The process of claim 13, wherein the sulfite ionic species is a potassium salt of sulfite.

19. The process of claim 13, wherein the sensitizer capable of absorbing UV radiation is sodium iodide or potassium iodide.

20. The process of claim 13, wherein the one or more bases are added in an amount sufficient to bring the pH of the solution to greater than 13.2.

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