Piezoelectric mechanochemical decontamination system and method for the destruction of per and polyfluorinated substances

Abstract

The present invention to is directed to a piezoelectric mechanochemical decontamination system. The system includes a piezoelectric material, impact medium, and dynamic impact device having a receiving chamber that receives the piezoelectric material, impact medium, and a PFAS-contaminated substance having a solid-and / or semi-solid-state PFAS. The dynamic impact device causes the impact medium to collide with the piezoelectric material to thereby cause a piezoelectric reaction that converts one-hundred percent of fluorine included in the PFAS-contaminated substance to fluoride and thereby converts the PFAS-contaminated substance to a decontaminated substance that is environmentally safe for disposal. The piezoelectric material is present at a molar ratio of at least 5:1 compared to the fluorine. The piezoelectric material includes boron nitride. The impact medium includes stainless steel or zirconium. The dynamic impact device is a planetary ball mill device, tumbler mill device, attritor mill device, or vibratory ball mill device.

Description

PIEZOELECTRIC MECHANOCHEMICAL DECONTAMINATION SYSTEM AND METHOD FOR THE DESTRUCTION OF PER AND POLYFLUORINATED SUBSTANCES CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63 / 617,918, filed January 5, 2024, which is hereby incorporated herein by reference. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] This invention was made with government support under a grant from the U.S. National Science Foundation Division of Chemical, Bioengineering, Environmental and Transport Systems Award No. 2120452, and U.S. National Science Foundation CAREER Award No.2237080. The U.S. Government has certain rights in this invention. TECHNICAL FIELD

[0003] The present invention relates to the field of piezoelectric mechanochemical technology, and more particularly to piezoelectric mechanochemical systems and methods for the destruction of per- and polyfluorinated substances (PFAS) contaminated waste. BACKGROUND

[0004] PFAS are synthetic chemicals that have been used since the 1940s. Their ubiquitous presence in the environment, significant toxicity, and persistence have garnered rapidly growing public concerns. Currently, the production and use of legacy PFAS, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), were not completely eliminated in some regions. Alternative PFAS are being manufactured globally. Some toxic alternatives, such as perfluorobutane sulfonic acid, GenX®(a short-chain organofluoride chemical compound), and telomers, are under scrutiny and facing forthcoming bans. Therefore, the cycle of “alternative development−assessment−elimination” is a long-lasting global effort that will lead to the continuous production of obsolete PFAS stockpiles. {9749593: } 1

[0005] The treatment of these chemical stockpiles is extremely challenging due to the large quantity and high concentration / purity. In water treatment sectors, adsorption by activated carbon (AC) or ion-exchange resin (IXR) is the only technology implemented at full-scale for PFAS removal. AC and IXR are very efficient for removing long-chain PFAS (i.e., 6 or more carbon atoms) and moderately effective for short-chain congeners. In other words, the spent sorbents could be loaded with various PFAS amidst other co- sorbates (e.g., salts, natural organic matter, etc.). Although AC and IXR could be reactivated and reused, the gradual performance loss is irreversible. Unlike stockpile treatment, spent sorbent disposal represents another fundamental challenge: the selective destruction of PFAS, at concentrations lower than chemical waste, in complex solid matrices.

[0006] PFAS-laden solid wastes are listed as hazardous wastes. Therefore, landfill disposal and incineration are the two contemporary solutions. Landfill disposal is an undesirable option, as it allows the re-entry of PFAS to the environment via leachate. Incineration was identified as the only interim technology by the United States Environmental Protection Agency (USEPA) in 2020. Prior solutions utilize thermal treatment at feverish temperature (e.g., greater than 700 °C) to completely decompose various PFAS alone or on sorbents. However, the volatilization of parent PFAS and the emission of organofluorine products were also observed. In 2021, the USEPA started to designate PFOA and PFOS as hazardous substances, which had led to a dramatic reduction of treatment capacity as only 22 out of 127 incineration facilities have permits to treat hazardous waste. More importantly, the public has expressed concerns about PFAS incineration via protests and lawsuits against agencies.

[0007] Prior art solutions for the destruction of solid-state PFAS are significantly lagging behind urgent social demands. The development of transformative non- incineration approaches is desperately needed. Non-incineration approaches for the disposal of PFAS in pure solids or concentrates include hydrothermal liquefaction and base-assisted decomposition. Although the aforementioned prior art laid the technical groundwork, additional challenges remain. Prior art solutions have been limited to addressing pure PFAS chemicals. Accordingly, there exists a need for an environmentally {9749593: } 2friendly PFAS decontamination solution that does not volatilize the parent PFAS, emit organofluorine products, or produce caustic byproducts. SUMMARY OF THE INVENTION

[0008] It is, therefore, an aspect of the present invention to provide a piezoelectric mechanochemical decontamination system having a piezoelectric material, impact medium, and dynamic impact device having a receiving chamber that receives the piezoelectric material, impact medium, and a PFAS-contaminated substance having a solid- and / or semi-solid-state PFAS; wherein the dynamic impact device causes the impact medium to collide with the piezoelectric material to thereby cause a piezoelectric reaction that converts one-hundred percent of fluorine included in the PFAS- contaminated substance to fluoride and thereby converts the PFAS-contaminated substance to a decontaminated substance that is environmentally safe for disposal; wherein the piezoelectric material is present at a molar ratio of at least 5:1 compared to the fluorine; wherein the piezoelectric material includes boron nitride; wherein the impact medium includes at least one of stainless steel or zirconium; wherein the dynamic impact device is a planetary ball mill device, tumbler mill device, attritor mill device, or a vibratory ball mill device; wherein the dynamic impact device is a jet mill device, a disc mill device, or a rod mill device; and wherein the impact medium includes a geometric structure that is in the shape of a pin, disc, triangle, cylinder, rectangle, and / or rod. The piezoelectric material includes at least one of strontium titanate and lead titanate. The PFAS- contaminated substance comprises at least one of a solid, liquid concentrate, wastewater, foam, sorbent, soil, biosolid, and sediment.

[0009] Another aspect of the present invention is to provide a piezoelectric mechanochemical decontamination method. The method may include combining a piezoelectric material, impact medium, and PFAS-contaminated substance in a receiving chamber of a dynamic impact device; initiating the dynamic impact device to thereby cause the impact medium to collide with the piezoelectric material in a manner that causes a piezoelectric reaction that converts one-hundred percent of fluorine included in the PFAS-contaminated substance to fluoride and thereby converts the PFAS-contaminated substance to a decontaminated substance that is environmentally safe for disposal; and {9749593: } 3separating the impact medium from the decontaminated substance prior to disposal of the decontaminated substance; wherein the step of initiating the dynamic impact device to thereby cause the impact medium to collide with the piezoelectric material and thereby cause the piezoelectric reaction includes causing the piezoelectric reaction to occur for a predetermined time period; wherein the PFAS-contaminated substance includes fluorine and the step of combining the piezoelectric material, the impact medium, and the PFAS- contaminated substance in the receiving chamber includes combining the piezoelectric material at a molar ratio of at least 5:1 compared to the fluorine; wherein the piezoelectric material includes boron nitride; wherein the impact medium includes at least one of stainless steel or zirconium; wherein the dynamic impact device is a planetary ball mill device, tumbler mill device, attritor mill device, or a vibratory ball mill device; wherein the dynamic impact device is a jet mill device, a disc mill device, or a rod mill device; wherein the impact medium includes a geometric structure that includes a pin, disc, triangle, cylinder, rectangle, and / or rod; and wherein the PFAS-contaminated substance includes at least one of a solid, liquid concentrate, wastewater, and foam. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings form a part of this specification and are to be read in conjunction therewith, wherein reference will be made, by way of example, to the accompanying drawings, and wherein:

[0011] FIG. 1 is a flowchart depicting the operational steps of a piezoelectric mechanochemical decontamination method for decontaminating PFAS-contaminated substances, in accordance with an embodiment of the present invention;

[0012] FIGS.2a and 2b are bar graphs depicting the effects of the molar ratio of BN vs. [Fluorine on PFAS], and co-milling reagents on the PFOA removal efficiency and defluorination efficiency, in accordance with an embodiment of the present invention;

[0013] FIG. 3a – 3d are graphs depicting the destruction and defluorination of PFOA and PFOS as ball milling treatment, in accordance with an embodiment of the present invention; {9749593: } 4

[0014] FIGS. 4a – 5f are graphs depicting the decay of parent PFAS and defluorination with different piezoelectric material (PZM), in accordance with an embodiment of the present invention;

[0015] FIG. 5 is a table depicting the data of defluorination efficiency (DeF%) calculation, in accordance with an embodiment of the present invention;

[0016] FIGS.6a and 6b are bar charts depicting the destruction profiles for PFCAs and PFCAs / FTS in sediment with boron nitride (BN) as the PZM, in accordance with an embodiment of the present invention;

[0017] FIGS. 7a and 7b are bar charts depicting the destruction of PFCAs and PFCAs / FTS in sediment with KOH as the PZM, in accordance with an embodiment of the present invention;

[0018] FIGS.8a and 8b are photographs illustrating the result of co-milling 20 mmol of BN and 20 mmol of KOH with 2 grams of sediments after 6 hours of BM treatment, in accordance with an embodiment of the present invention;

[0019] FIGS.9a – 9c are graphs depicting PFOS destruction profiles, the reaction rate constant, and defluorination efficiencies, respectively, in accordance with an embodiment of the present invention;

[0020] FIGS.10a – 10f are time profiles of FTS, other PFAS, and Def% of BN-BM treatment of AFFF, respectively, in accordance with an embodiment of the present invention;

[0021] FIGS.11a – 11c are line charts depicting the results of BN-BM treatment of PFOS absorbed on AERs, in accordance with an embodiment of the present invention;

[0022] FIG.12 is a bar graph depicting fluoride (F-) and DeF% after different milling times, in accordance with an embodiment of the present invention;

[0023] FIGS. 13a and 13b are bar graphs depicting the destruction of PFAS on field-collected spent AERs, in accordance with an embodiment of the present invention; and

[0024] FIGS. 14a – 14f are line graphs depicting the destruction and DeF% of PFCAs, PFSAs, HFPO-DA, and bisMeSI processed via BN-BM treatment, in accordance with an embodiment of the present invention. {9749593: } 5DETAILED DESCRIPTION

[0025] The descriptions of the various embodiments of the present invention have been presented for purposes of illustration but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

[0026] In the figures, elements having an alphanumeric designation may be referenced herein collectively or in the alternative, as will be apparent from context, by the numeric portion of the designation only. Further, the constituent parts of various elements in the figures may be designated with separate reference numerals which shall be understood to refer to that constituent part of the element and not the element as a whole. The terms “a” and “an” refer to at least one element or component referenced therein.

[0027] Per- and polyfluorinated substances (PFAS) are synthetic chemicals that have been used since the 1940s. Their ubiquitous presence in the environment, significant toxicity, and persistence have garnered rapidly growing public concerns. Currently, the production and use of legacy PFAS, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), were not completely eliminated in some regions. Alternative PFAS are being manufactured globally. Some toxic alternatives, such as perfluorobutane sulfonic acid, GenX®(a short-chain organofluorine chemical compound), and telomers, are under scrutiny and facing forthcoming bans. Therefore, the cycle of “alternative development−assessment−elimination” is a long-lasting global effort that will lead to the continuous production of obsolete PFAS stockpiles.

[0028] The treatment of these chemical stockpiles is extremely challenging due to the large quantity and high concentration / purity. In water treatment sectors, adsorption by activated carbon (AC) or ion-exchange resin (IXR) is the only technology implemented at full-scale for PFAS removal. AC and IXR are very efficient for removing long-chain PFAS (i.e., 6 or more carbon atoms) and moderately effective for short-chain congeners. In {9749593: } 6other words, the spent sorbents could be loaded with various PFAS amidst other co- sorbates (e.g., salts, natural organic matter, etc.). Although AC and IXR could be reactivated and reused, the gradual performance loss is irreversible. Unlike stockpile treatment, spent sorbent disposal represents another fundamental challenge: the selective destruction of PFAS, at concentrations lower than chemical waste, in complex solid matrices.

[0029] PFAS-laden solid wastes are listed as hazardous wastes. Therefore, landfill disposal and incineration are the two contemporary solutions. Landfill disposal is an undesirable option, as it allows the re-entry of PFAS to the environment via leachate. Incineration was identified as the only interim technology by the United States Environmental Protection Agency (USEPA) in 2020. Prior solutions suggest that thermal treatment at temperatures greater than 700 °C can completely decompose various PFAS alone or on sorbents. However, the volatilization of parent PFAS and the emission of organofluorine products were also observed. In 2021, the USEPA started to designate PFOA and PFOS as hazardous substances, which will lead to a dramatic reduction of treatment capacity as only 22 out of 127 incineration facilities have permits to treat hazardous waste. More importantly, the public has expressed concerns about PFAS incineration via protests and lawsuits against agencies.

[0030] Prior art solutions for the destruction of solid-state PFAS are significantly lagging behind urgent social demands. The development of transformative non- incineration approaches is desperately needed. Non-incineration approaches for the disposal of PFAS in pure solids or concentrates include mechanochemical ball mill, hydrothermal liquefaction, and base-assisted decomposition. Among these technologies, only mechanochemical ball milling (BM) can be operated at atmospheric temperatures and pressures to treat solids directly without solvents. To date, the destruction of selected pure PFAS compounds (e.g., PFOS, PFOA, telomers, etc.) has been demonstrated in laboratory experiments using different co-milling reagents (e.g., CaO, KOH, Al2O3, La2O3, ferrate, persulfate, and SiO2). KOH is the only co-milling reagent that achieved about 90% conversion of fluorine on PFOS to fluoride (F-).

[0031] Although the aforementioned prior art laid the technical groundwork, additional challenges remain. First, the current KOH-BM systems require excessive {9749593: } 7chemical doses (e.g., KOH vs. PFAS mass ratio greater than 20:1). The treated caustic solid is not environmentally friendly and requires further processing prior to discharge or reuse. Further, KOH-BM systems exhibit low water resistance. Environmental humidity and moisture in the solid cause agglomeration of KOH powders, which consequently hinders the piezoelectric reaction. Prior art solutions have been limited to addressing pure PFAS chemicals. Consumers would benefit from an environmentally friendly PFAS decontamination solution that does not hinder the piezoelectric reaction, volatilize the parent PFAS, emit organofluorine products, or produce caustic byproducts.

[0032] Embodiments of the present invention seek to provide piezoelectric mechanochemical decontamination systems and methods for the defluorination of PFAS- contaminated substances (e.g., solids, semi-solids, liquid concentrates, wastewater, and foams). PFAS liquid concentrates are often used in firefighting foams and other industrial applications. Other aspects of the present invention seek to provide PFAS decontamination solutions that do not result in caustic or toxic waste (i.e., are environmentally friendly). Additional aspects of the present invention seek to provide PFAS decontamination solutions that produce decontaminated products that are landfill ready without the need for additional processing.

[0033] The piezoelectric mechanochemical decontamination (PEMCD) system preferably includes at least one piezoelectric material (PZM), impact medium, and dynamic impact device. As discussed below, the preferred PZM for the PEMCD system includes boron nitride (BN). In certain embodiments, the PZM can include strontium titanate and / or lead titanate. In other embodiments, the PZMs include zinc oxide, silica dioxide, and / or barium titanate. In general, the PZM is chosen for its ability to cause a piezoelectric reaction that converts 100% of PFAS fluorines to fluoride without resulting in caustic and / or toxic byproducts. The impact medium preferably includes stainless steel and / or zirconium. Alternatively or in addition, the impact medium can include any substrate that can compress the PZM in a manner to initiate the piezoelectric reaction and without producing caustic and / or toxic byproducts.

[0034] While the impact medium is depicted herein as balls, the impact medium can have any geometric shape / structure that supports one or more disclosed embodiments, including, but not limited to, a pin, disc, triangular, cylinder, rectangular, {9749593: } 8round, ovular, and / or rod shape. The PEMDC system uses piezoelectric reactions to convert fluorine (toxic) to fluoride (safe). A piezoelectric reaction refers to the generation of an electric charge in certain materials when they are subjected to mechanical stress. When these materials are compressed, twisted, or otherwise mechanically deformed, they produce an electrical voltage across their surfaces. The dynamic impact device is preferably a device that can cause the impact medium to collide with the PZM to thereby cause the piezoelectric reaction, which subsequently induces a piezoelectric oxidation pathway that causes the destruction of PFAS. For example, the dynamic impact device can be a planetary ball mill (BM) device, tumbler mill device, attritor mill device, vibratory ball mill device, jet mill device, disc mill device, and / or rod mill device.

[0035] The dynamic impact device includes at least one receiving chamber that receive the PZM, impact medium, and a PFAS-contaminated substance that includes solid- and / or semi-solid-state PFAS. In preferred embodiments, the PZM is present at a molar ratio of at least 5:1 compared to the fluorine included in the PFAS-contaminated substance. The types of PFAS-contaminated substances that can be treated with the treated with the PEMDC include, but are limited to, solids, liquid concentrates, wastewater, and foams. PFAS liquid concentrates are often used in firefighting foams and other industrial applications. For example, applicable solids can at least include sorbents, resins, soil, biosolids, and sediments. Wastewater included but not limited to semiconductor fabrication wastewater, membrane concentrates, still bottom solutions produced from resin regeneration, landfill leachate, etc.

[0036] The dynamic impact device is configured to cause the impact medium to collide with the PZM to thereby cause a piezoelectric reaction (e.g., a piezoelectric oxidation reaction) that converts one-hundred percent of fluorine included in the PFAS- contaminated substance to fluoride and thereby convert the PFAS-contaminated substance to a decontaminated substance that is environmentally safe for disposal.

[0037] Turning now to the Figures. FIG. 1 depicts a flowchart of the operational steps of a PEMDC method for decontaminating PFAS-contaminated substances, according to some embodiments. At Step 110, a PZM, impact medium, and PFAS- contaminated substance are combined in the receiving chamber(s) of a dynamic impact device. In some embodiments, the PZM is combined at a molar ratio of at least 5:1 {9749593: } 9compared to the fluorine of the PFAS-contaminated substance (Step 120). At Step 130, the dynamic impact device is initiated to thereby cause the impact medium to collide with the PZM and thereby cause a piezoelectric reaction that converts one-hundred percent of fluorine included in the PFAS-contaminated substance to fluoride and thereby convert the PFAS-contaminated substance to a decontaminated substance that is environmentally safe for disposal.

[0038] Alternatively or in addition, the piezoelectric reaction is caused to occur for a predetermined period of time (e.g., at least 60 minutes, 120 minutes, etc.). When the fluorine has all been converted fluoride, the decontaminated substance can be disposed of. For example, at Step 150, the impact medium can be separated from the decontaminated substance prior to disposal thereof. In certain embodiments, the impact medium can be disposed of with the decontaminated substance.

[0039] Aspects of the below examples are described in greater detail in the following journal articles: Zhu J, Yang N, Fernando S, Holsen T, and Yang Y. “Piezoelectric Ball Milling Treatment of PFAS-Laden Spent Resins.” ChemRxiv.2024. Doi:10.26434 / chemrxiv-2024-zj5hk; and Yang N, Guan Y, Yang S, Olive C, Fernando S, Holsen T, et al. “PFAS Destruction and Near Complete Defluorination of Undiluted Aqueous Film-Forming Foams at Ambient Conditions by Piezoelectric Ball Milling.” ChemRxiv. 2024. doi:10.26434 / chemrxiv-2024-dmvk9.These articles are hereby incorporated by reference in its entirety into this application.

[0040] WORKING EXAMPLES

[0041] Methods and Materials.

[0042] All the reagents used were at least analytical grade, except as noted. BN, Potassium hydroxide (KOH), formic acid (HCOOH), Superclean ENVI-Carb, Perfluorooctanoic acid (PFOA), Heptadecafluorooctanesulfonic acid potassium salt (PFOS) was obtained from Sigma-Aldrich Co. (USA). Acetonitrile was purchased from Fisher Scientific. Superclean ENVI-Carb was purchased from SUPELCO, Inc (PA, USA). Ball milling (BM) treatment was conducted on a planetary ball mill (PQ-N04, Across International, USA). The mill has four stainless steel (SS) jars (100 mL) filled with SS balls (10 large balls at a diameter of 10 mm and 106 small balls at a diameter of 6 mm). The SS jars and balls can be replaced with counterparts made of zirconia to exclude the {9749593: } 10potential interference of iron leaching. PFAS-containing samples (chemicals or sediments) and co-milling reagents were added to the jars, which were then covered by jar lids. All trials were performed at laboratory room temperature and atmospheric pressure. The grinding jar remained closed during milling and was opened for sampling. The atmosphere in the headspace was not deliberately controlled, thereby should be air.

[0043] For tests aimed to destruct solid PFOA, the solid after BM treatment was ultrasonically extracted with 50 mL Milli-Q water for 30 min. After centrifuge separation, the supernatants were diluted by 75% / 25% methanol / water and analyzed by UPLC- MS / MS. As for the ball milling destruction of PFOS, the analytical procedure was identical, except methanol was used as the extraction solvent.

[0044] Sample extraction, quality control, and PFAS analysis by liquid chromatography coupled to a triple quadrupole mass spectrometer (LC-MS / MS) were conducted. Comilling reagents, alone or mixed with PFAS, were characterized by piezoelectric, infrared, and X-ray-based techniques. PFAS in extracts were analyzed by ultra-high-performance liquid chromatography (UPLC, Thermo Vanquish) coupled to a triple quadrupole mass spectrometer (MS / MS, Thermo Altis). Briefly, a 5 μL sample was injected and then separated on a Phenomenex Luna Omega column (100 × 2.1 mm, 1.6 μm particle size, C18 stationary phase). The column was maintained at 40 °C at a flow rate was 0.5 mL / min. The mobile phases consisted of 5 mM ammonium acetate in water (Mobile Phase A) and Acetonitrile (Mobile Phase B). The LC gradient used was as follows: 0 min (30% B), 0.5 min (30% B), 3 min (90% B), 3.1 min (100% B), 4.5 min (100% B), 4.6 min (30% B) and 6.5 min (30%B). Multiple reaction monitoring (MRM) was utilized for MS analysis, whereby the transition S4 between precursor and fragment ions was monitored. Sample acquisition and analysis were performed with TraceFinder 4.1 (Thermo Scientific).

[0045] Fluoride analysis was conducted on a Dionex Integrion ion chromatography system with an anion-exchange column (Thermo Fisher Scientific, RFIC™ IonPac™ AS18 column). AS-18 column was used with a KOH solution (23 mM) as the eluent, flow rate = 1 mL / min, and the suppressor current was set at 57 mA.

[0046] Total fluorine (TF) analysis was exclusively adopted in the tests of sediment treatment. The combustion ion chromatography (CIC; Metrohm, Switzerland) instrument {9749593: } 11combines ion chromatography (IC) (930 Compact IC Flex, with conductivity detection), an absorber module where the gaseous compounds of the analytes, formed during combustion, are dissolved and channeled to the IC (920 Absorber Module), and an automatic combustion module (Analytik Jena). The separation of ions occurs on a Metrosep A Supp 5150 / 4.0 column combined with a Metrosep A Supp 4 / 5 guard column. Sediment samples were combusted directly to analyze total fluorine. Other operating conditions used are as follows: 1050 °C combustion temperature, 100 mL / min of argon as the carrier gas; 300 mL / min of oxygen as the combustion gas; Milli-Q (18 mΩ cm; 0.56 μS / cm) water as the absorber solution; 1.0 mL min-1 mobile phase (0.32 M / 0.10 M sodium carbonate / bicarbonate); 1 mL sample loop; 30 °C column temperature; an eleven- point calibration curve using sodium fluoride (0 to 500 μg / L). All solutions (sample dilutions and standards) were prepared with Milli-Q water. The minimum detection limit (MDL) was 5 μg / L, and the limit of quantification (LOQ) was 20 μg / L. It is reasonable to assume that TF is a sum of inorganic fluoride (measured by IC) and total organic fluorine (TOF). Therefore, TOF values were calculated by subtracting the fluoride amounts (detected in the washing solution by IC, in μmol) from TF (measured by CIC, in μmol).

[0047] Ball Milling Activation of Piezoelectric Boron Nitrate.

[0048] Prior art solutions show that KOH–BM processes use BM to promote the nucleophilic substitution of OH–to the carbon backbone of PFAS. The BN–BM process of the present invention operates on a different principle and is motivated by the fact that PFAS oxidation is thermodynamically feasible at high redox potential (>4 VRHE) in aqueous solutions. To realize the electrocatalytic oxidation of PFAS in solid matrices, the present invention posits that the reaction system requires the solid–solid contact of PFAS and catalytic materials charged with high potentials.

[0049] Based on the foregoing, PZMs are determined to be the ideal comilling reagent. PZMs are crystals with noncentrosymmetric structures. Upon mechanical impact, the atomic displacement of PZMs causes a mismatch between the cation and anion centers, generating a dipole moment. The cumulative buildup of the dipole moments creates piezoelectric (PZ) potentials. For instance, applying stress in the normal direction results in polarization in the same direction. With these in mind, the present invention posits that ball collisions acting on PZMs can generate high PZ potentials to {9749593: } 12destroy PFAS. The commercial BN sample has a particle diameter of 1–3 μm. The analysis of BN by piezoresponse force microscopy (PFM) gave the PZ coefficient under 33-mode activation, d33, as 19.4 pm / V, which is within the reported range (18–41 pm / V).

[0050] Tapping mode using SCM-PIT-V2 tip (0.1 N / M, Bruker) was used to test the surface topography, and PFM in contact mode was used to investigate the piezoelectric properties in a 15 kHz AC electric field. The principle of PFM is based on the detection of bias-induced surface deformation. Specifically, it brings a sharp conductive probe into contact with a piezoelectric material. Then, an alternating current (AC) bias is applied to the probe tip to induce the deformation of the sample through a converse piezoelectric effect. The piezoelectric response of the surface is detected as the first harmonic component of bias-induced tip deflection.

[0051] Based on a general model developed for the planetary ball mill, the radial impact force, FR (N), produced by the BM process is estimated to be 57 N at a jar rotation speed of 580 rpm. The PZ potential can then be estimated using the following equation: PZ = d33FRZ / ^0^rA where A = 1 × 10–12m2is the impact area (assuming the force acts on a 1 μm × 1 μm square BN), Z is the depth of the BN flake normal to the impact direction (30 nm), ε0 is the permittivity (8.85 × 10–12F / m), and εr is the relative dielectric constant of BN (3.5).

[0052] Based on the foregoing, the theoretical calculation gives a high PZ potential of ∼3000 V. If the midpoint of the PZ potential is arbitrarily set as the Fermi level of BN (−3.6 VRHE), then the 3000 V is composed of −1504 VRHE cathodic potential and 1496 VRHE anodic potential. The latter value readily surpasses the 4 VRHE criteria for PFAS destruction. Note that the calculated value represents the ideal scenario in which a ball hits a single BN flake at the maximum impact velocity. The actual time-averaged PZ potential in a mixed powder system might vary. The above calculations indicate that there may be unparalleled redox capability of BN unleashed by BM activation.

[0053] Example 1. Comparing the Effectiveness of Boron Nitrate and Potassium Oxide for the Destruction of PFAS Chemicals {9749593: } 13

[0054] FIGS.2a and 2b are bar graphs that depicts the effects of the molar ratio of BN vs. [Fluorine on PFAS], and co-milling reagents on the PFOA removal efficiency and defluorination efficiency, respectively, according to certain embodiments of the present invention. First, the efficacy of BN-BM to destroy and defluorinate PFOA and PFOS solid powders was evaluated. For all the tests, the jar rotation speed was 580 rpm, and treatment duration was one hour. As shown, PFOA and PFOS were readily destroyed after 1 hour. In test set of FIG.2b, 19 mmol of BN or KOH was co-milled with 0.23 mmol of PFOA. Fluoride was gradually released as one of the final products. The defluorination efficiency (DeF%) was calculated using the following equation: DeF% =[F−]⁄ (^^0 × ^^) × 100%where, [F-] is the fluoride molar mass detected in the extraction solution, m0 is the molar mass of PFAS added to the jar, and n is the number of fluorine atoms on a PFAS molecule.

[0055] It is critical to highlight that, for the first time, near-quantitative defluorination (i.e., DeF% = ~100%) of PFOS and PFOA was achieved after four hours of treatment. As a comparison, the best performing KOH-BM approach could not achieve complete defluorination of PFOS, and the DeF% is between 80-90%. To unbiasedly compare the performance of two co-milling reagents, parallel treatment of PFOA and PFOS using KOH−BM and BN−BM approaches was conducted. The [reagent] vs. [F−PFAS] molar ratio was set as 5:1 for all reactions. The treatment was performed for one hour. As shown in FIG.2b, the BN−BM process (100% destruction and 80% DeF%) outperformed theKOH − BM process (70% destruction; 40~50% DeF%). Additional tests yieldedcomparable results.

[0056] FIGS.3a and 3c are graphs depicting the destruction of (a) PFOA and (c) PFOS and formation of shorter-chain intermediates, namely perfluoroheptonic acid (PFHpA), perfluorohexanoic acid (PFHxA), perfluoropentanoic acid (PFPeA), perfluorobutonic acid (PFBA), pentafluoropropionic anhydride (PFPA), and trifluoroacetic acid (TFA). FIGS. 3b and 3d are graphs depicting near-quantitative defluorination of {9749593: } 14PFOA and PFOS, respectively, after one hour of ball milling treatment. In addition to the destruction of parent PFAS, shorter-chain intermediates were produced and then destroyed, which implies that the BN−BM treatment performance is independent of chain length.

[0057] Example 2. Comparing the Effectiveness of BN and SiO2 for the destruction of PFAS chemicals

[0058] FIGS.4a-4c are graphs depicting the decay of parent PFAS. FIGS.4d-4f are graphs depicting the defluorination with different co-milling reagents during ball milling treatment. FIGS.4a-4c compare the performance of BN−BM and SiO2−BM treatment on the destruction and defluorination of 6:2 fluorotelomer sulfonate (FTS), PFOA, and PFOS. The BN-BM treatment used a [BN] vs. [F on PFAS] molar ratio of 5:1, while the SiO2−BM treatment adopted a [SiO2] vs. [F on PFAS] molar ratio of 20:1. Even though the molar dosage of BN was one-fourth that of SiO2, BN still exhibited faster removal kinetics for all PFAS than SiO2 alone.

[0059] Quartz sand (SiO2) is a co-milling reagent known in the art for PFOS and PFOA destruction, but has a low DeF% of less than 20%. Solid-state nuclear magnetic resonance (NMR) spectroscopy showed that insoluble Si-F bonds are formed by this process, which explains the low recovery of F- by solvent extraction in such experiments. Importantly, in the instant investigation, the BN−BM treatment readily achieved greater than 98% DeF% for 6:2 FTS, PFOA, and PFOS (FIGS.4d-f; raw data see FIG.5), while less than 25% DeF% was observed in treatments using only SiO2. Here, the initial mass of 6:2 FTS, PFOA, and PFOS were 0.3, 0.23, and 0.23 mmol, respectively. For all treatments using BN and SiO2 separately or combined, the molar ratio of [BN] vs. [F on PFAS] was 5:1; the molar ratio of [SiO2] vs. [F on PFAS] was 20:1.

[0060] Example 3. Comparing the Effectiveness of BN and KOH for the Treatment of PFAS-Laden Sediments

[0061] The BN−BM treatment was further applied in treating PFAS-contaminated sediment. Sediment samples were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS / MS). Of the 30 PFAS-contaminated sediment samples analyzed via the LC−MS / MS method, 21 PFAS were detected in sediment. The sediment was subsequently subjected to BN−BM treatment. As shown in FIG.7, while treatment time {9749593: } 15increased, the gradual destruction of perfluoroalkylcarboxylic acids (PFCAs), perfluoroalkanesulfonic acid (PFSAs), and 6:2 FTS was observed. Here, degradation kinetics are independent of chain lengths and configurations (branched vs. linear). About 80% of the measured PFAS were removed after six hours. Higher destruction efficiencies were obtained by extending the treatment time to ten hours. As a comparison, the PFAS- contaminated sediments were also treated by the KOH−BM process at a KOH dose equal to BN (20 mmol). However, much slower PFAS destruction kinetics were observed compared with the BN−BM treatment process, as the six-hour removal efficiencies for PFCA and PFSA were only 19% and 24 %, respectively. See FIG.7.

[0062] FIGS.6a and 6b are bar graphs depicting the destruction profiles for PFCAs and PFSAs / FTS, respectively, in sediment with BN as the co-milling reagent. The ~80% destruction of PFAS after a 6-hour treatment is calculated to generate 15.1 µmol fluoride (F-). Surprisingly, a much higher net yield of 37.2 µmol F- was detected in sediment after BN–BM treatment. The sediments are impacted by aqueous film-forming foam (AFFF), which is a type of firefighting foam used to extinguish flammable liquid fires, such as those involving fuels. AFFF consist of water, liquid foam concentrate, and fluorinated surfactants like PFOS and PFOA.

[0063] Therefore, the presence of PFAS precursors beyond the 21 target PFAS detected is expected, leading to greater fluoride yield after destruction. Analyses combining combustion ion chromatography (CIC) and ion chromatography (IC) showed that sediment contained 70 μmol total organic fluorine (TOF) / g sediments. Six-hour BM treatment by BN and KOH destroyed 26% and 20% of TOF, respectively. These results highlight the promise of the BN–BM treatment in destroying fluorocarbons that are not included in the analytical methods of the prior art.

[0064] FIGS.8a and 8b are photographs illustrating the result of co-milling 20 mmol of BN and 20 mmol of KOH with 2 grams of sediments after 6 hours of BM treatment, respectively. The moisture content of the sediment was 7.8% as measured gravimetrically by oven-drying the sample at 105 °C for 24 hours. These results suggest that BN–BM treatment has higher water resistance than KOH–BM treatment. Further, the KOH powder agglomerated on the stainless steel balls (i.e. the impact medium) due to its hygroscopicity. The balls became sticky, which retarded their free collision movement. In {9749593: } 16contrast, BN aggregation was not observed because BN is not soluble in water and thus is not hygroscopic.

[0065] Another significant advantage of BN-BM treatment over KOH − BMtreatment is that BN−BM does not produce caustic solid waste. The extract solution (40 mL H2O to extract 2 g sediment) derived from sediment treated by BN−BM had a pH of 9.9, which was significantly lower than that (pH 14.2) of sediment derived from KOH−BM.

[0066] Example 4. Comparison of Different Piezoelectric Materials

[0067] FIGS.9a – 9c are graphs depicting PFOS destruction profiles, reaction rate constant, and defluorination efficiencies, respectively, in accordance with some embodiments. Here, a comprehensive investigation on the destruction of PFOS by four types of piezoelectric materials (PZMs): piezoelectric nitride (BN), metal oxides (ZnO, BaTiO3 and PbTiO3) was analyzed. The ball mill rotation speed was 580 rpm. The molar ratio of [BN] vs. [F on PFAS] was set as 5:1. BN and BaTiO3 achieved complete destruction of PFOS after 45 min, whereas ZnO and PbTiO3 exhibited slower degradation kinetics. See FIG. 9a. In general, the PFOS degradation kinetic constants were proportional to the piezoelectric potentials generated by various PZMs. See FIG.9b. This finding consolidates the principle of PZM-assisted ball milling. As shown in FIG.9c, BN is the only co-milling reagent that achieved 100% defluorination of PFOS (i.e., all fluorine atoms on PFOS were turned into F-). These findings underscore the superiority of BN- BM treatment over the other approaches, which either failed to achieve or did not report 100% defluorination.

[0068] Example 5. Use of Piezoelectric Ball Milling to Treat Aqueous Foam- Forming Foam (AFFF)

[0069] FIGS.10a – 10f are time profiles of FTS, other PFAS, and Def% of BN-BM treatment of AFFF, respectively, according to other embodiments of the present invention. In the treatment of AFFF, milled samples containing co-milling reagent and AFFF were extracted using 50 mL of 50% MeOH. The mixture of solvents and solids was subjected to 15-min sonication and 6-min centrifugal separation at 5000 rpm. The resulting supernatant (i.e., extract) was then diluted to 75% methanol by 10-100 times for instrumental analysis. The BM-treated samples were extracted using Milli-Q water for the analyses of F- and TOC. F- in the extracts was analyzed by a Dionex Aquion {9749593: } 17chromatography system with an anion-exchange column (Thermo Fisher Scientific, RFIC™ IonPac™ AS18 column). The detection limit of F- was 50 μg / L. Quantification of TOC was conducted on a SHIMADZU TOC-L instrument that had a detection limit of 0.2 mg / L.

[0070] The TF of AFFF was determined by combustion ion chromatography (CIC; Metrohm). AFFF was diluted 500 times with Milli-Q water. Diluted AFFF (100 μL) was decomposed at 1050 °C in the combustion module (Analytik Jena), and fluorine carried by argon gas was trapped by a 920 absorber module as F-, which was quantified by IC (930 Compact IC Flex). The CIC measurement TF detection limit of 5 μg / L. Since no F- was detected in the AFFF, the TOF of AFFF samples equals their TF. Compared with other methods of TF estimation using targeted PFAS analysis (led to underreporting of TF) and total oxidizable precursor assay (results subjected to digestion conditions), CIC is the most suitable baseline for establishing a fluorine balance in this study.

[0071] Here, the ball mill jar rotation speed was 580 rpm and data is presented as mean values of triplicates ± standard deviation. The AFFF (Platinum Plus C63% AFFF by Buckeye Fire Equipment) was treated as received without dilution. Milling 0.5 g BN with 100 μL of AFFF led to the destruction of FTS, accompanied by the generation and decay of perfluoroalkyl carboxylic acids (PFCAs). See FIGS.10a and 10b. Achieving bulk defluorination of AFFF was more challenging than destroying target PFAS due to matrix complexity. Surprisingly, after 6 hours of treatment, 99.7% defluorination of AFFF was achieved. See FIG. 9c. The performance of the BN−BM process in treating a doubled amount of AFFF (200 μL) was further analyzed. Significant PFAS destruction was observed after six hours. See FIGS. 10d and 10e. In addition, more than 98% defluorination was still achieved after a prolonged treatment duration of 8 hours. See FIG. 10f.

[0072] In preferred embodiments, the impact medium and receiving chamber should be coated with the AFFF at a thickness (Z) up to 2.3 μm (Critical Liquid Film Thickness, CLFT). When Z is less than CLFT, the delivery of impact energy to BN and the consequent PFAS destruction is effective. However, when Z is greater than CLFT, the drag force offsets the impact force enough to retard PFAS destruction. The present invention is the first demonstration of deep defluorination of liquid undiluted AFFF by {9749593: } 18piezoelectric BM at ambient temperatures and pressures. The present invention addresses the critical need for non-thermal AFFF treatment and identifies CLFT as the critical descriptor for the BM treatment of liquid waste.

[0073] Example 6. Use of Piezoelectric Ball Milling to Treat PFAS-Contaminated Resin

[0074] Turning now to FIGS.11a – 11b. PFA694E anion exchange resins (AERs) spiked in with PFAS were pulverized by ball milling with stainless steel (SS) balls without BN for one hour and extracted to yield time-zero PFOS concentrations. PFA694E is a type of ion exchange resin developed by Purolite™, specifically designed for the removal of PFAS from water. Control tests were conducted by further milling the pulverized AERs for an additional eight hours in the absence of BN. The key finding from these tests was that ball milling in the absence of BN could not destroy PFOS. To initiate PFAS destruction, BN powders were added following one hour of pulverization. Measurable destruction of PFOS adsorbed on AERs was observed after the addition of BN, with degradation kinetics accelerating with increased BN loading. See FIG.11a. Comilling of 750 mg BN with 280 mg AERs (BN / AER mass ratio of 2.7) resulted in near-complete destruction of PFOS after three hours of treatment. The faster PFOS degradation kinetics at higher BN doses can be attributed to the enhanced contact between BN and the AERs.

[0075] The treatment of PFOS-contaminated AERs (Amberlite PSR2 Plus) was compared with the destruction of PFOS-contaminated solids at equivalent amounts to determine the role of the resin in PFOS destruction. See FIG. 11b. Here, the PFOS embedded in AERs exhibited slower degradation kinetics, suggesting that the AERs act as an inert matrix and shield the impact force exerted on BN, thereby attenuating the piezoelectric potential. The impact force can be increased by an increase of ball to powder mass ratio (B / P ratio, where the powder includes BN particles and AERs). By optimizing the BN-to-AER ratio, near-complete destruction of PFOS on regenerable IRA 67 AERs was achieved. See FIG.11c.

[0076] FIG.12 is a bar graph depicting fluoride (F-) and DeF% after different milling times, in accordance with some embodiments of the present invention. PFOS-loaded PFA694E AERs (280 mg; 2.3 mg PFOS / g AERs) was milled with 750 mg BN at a jar rotation speed of 580 rpm. After 24 h of milling, 80% of the fluorine on PFOS loaded on {9749593: } 19the AERs was recovered as F-. FIGS.13a and 13b are bar graphs depicting destruction of PFAS on field-collected spent AERs, in accordance with some embodiments of the replace invention. FIG.13a reflects the results of the treatment of PFA 694, while FIG. 13b reflects the treatment of Amberlite PSR2 Plus. To begin, 280 mg of AERs were co- milled with 750 mg of BN and 160 g stainless steel balls at a jar rotation speed of 580 rpm. Error bars represent the standard deviation of triplicate results.

[0077] The milling treatment was performed at a BN-to-AER mass ratio of 2.7:1. Before and after treatment, the AERs were extracted by a mixing solution of 80% MeOH and 3% NaCl for 24 hours, followed by the analysis of thirty target PFAS by UPLC- MS / MS. The extracts from the two AERs, sourced from different groundwater remediation projects, exhibited diverse PFAS profiles, covering C4-C8 PFSAs and PFCAs. The BN- BM treatment process effectively eliminated all target PFAS below the detection limits, irrespective of their chemical structures, after 24 h of milling.

[0078] Example 7. Use Piezoelectric Ball Milling to Treat PFAS-Laden Resin

[0079] FIGS. 14a – 14f are line graphs depicting the destruction and DeF% of PFCAs, PFSAs, HFPO-DA, and bisMeSI processed via BN-BM treatment, in accordance with other embodiments of the present invention. The molar ratio of [BN] vs. [F on PFAS] was 5:1, PFASs were present at 0.25 mmol, and the ball mill rotation speed was 580 rpm. The BN-BM treatment showed universal reactivity towards the destruction and complete defluorination of PFAS with various structures. Given the foregoing, the present invention presents comprehensive evidence for the treatment of EPA-regulated PFAS and emerging PFAS anticipated to be subject to future regulations.

[0080] Not to be limited by theory, the BN–BM destruction of PFAS follows the piezoelectric oxidation pathway. First, BN can generate ∼kV piezoelectric potentials upon collision with the impact material based on many findings. BN, as a neutral chemical, cannot induce electrophilic OH–substitution of PFAS. Although radicals may be generated at high PZ potentials, they are likely not the dominant contributor to PFOA and PFOS destruction due to their high resistance to radical attack. Reductive species (if any) are likely readily quenched by air in the receiving chamber (e.g., mill jar headspace). The jar temperature typically is less than 40 °C, and the BM destruction of PFAS did not occur without comilling reagents, excluding the possibility of thermolytic destruction. Lastly, the {9749593: } 20formation of short-chain intermediates following the −CF2– elimination pathway is observed, identical to the patterns in electrochemical oxidation reactions.

[0081] This disclosure posits that PFAS lose electrons to BN charged with high piezoelectric potentials via a direct electron transfer mechanism to form fluoroalkyl radicals, which are oxidized by either oxygen or radicals to form short-chain carboxylates. These steps were repeated until complete mineralization was achieved.

[0082] The investigations herein provide critical mechanistic insights: (1) PFAS contacts with BN were destroyed under high PZ potentials; (2) the F–ions released from the destroyed PFAS chemically bind on the out-of-plane B- and N-sites, changing them from sp2- to sp3-hybridized; and (3) after extraction by water, the fluorinated B- and N- sites, along with other edge B–N structures impaired by BM, were hydrolyzed to NH4+ / NH3 (pKa = 9.26), H3BO / H2BO3–(pKa1 = 9.15), and F–. The F–ions were readily extractable from BN, which explains the ∼100% fluoride recovery in PFOA and PFOS destruction.

[0083] It is important to highlight that BN, like many PZMs, is a semiconductor. To be sure, the prior art fails to show that BN as a photocatalyst can destroy PFSAs (e.g., PFOS). The present invention successfully demonstrates that the BN activated by BM can destroy PFSAs. The results imply that mechanochemical activation could bestow BN and possibly other PZMs with a stronger redox capability beyond the photocatalytic route. The broader impact of this disclosure is validating the superior performance of the piezoelectric BM process in treating PFAS in sediments.

[0084] The present invention presents a novel, non-thermal, solvent-free approach for treating PFAS-contaminated substances. The present invention involves a simple setup that co-mills PFAS-contaminated substances with BN and impact medium (e.g., SS balls). BN is a widely available industrial material. Given the economic considerations, the recovery and reuse of low-cost BN are not expected to be beneficial. Therefore, the BN will be blended with the decontaminated substances after treatment. During the PFAS degradation process, BN is expected to decompose into ammonium and borate. Even if residual BN particles remain, they are known to be biocompatible and non-cytotoxic. Ball mills, as mature industrial equipment, can be repurposed as effective treatment units. The theoretical analysis indicates that the ball impact velocity in planetary ball milling, {9749593: } 21measured at 1.5 m / s, is in the same order of magnitude as the value generated by tumbler mills. The piezoelectric mechanochemical decontamination system of the present invention can be constructed as a modular, portable, and / or trailer-based platform that allows onsite, solvent-free, non-thermal PFAS elimination wherein the decontaminated substances can be further disposed of as non-hazardous material through landfilling, thereby ensuring regulatory compliance.

[0085] The foregoing description of the preferred embodiment of the invention has been presented for the purpose of illustration and description. It is not intended to be exhaustive nor is it intended to limit the invention to the precise form disclosed. It will be apparent to those skilled in the art that the disclosed embodiments may be modified in light of the above teachings. The embodiments described are chosen to provide an illustration of the principles of the invention and its practical application to enable thereby one or ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Therefore, the foregoing description is to be considered exemplary, rather than limiting, and the true scope of the invention is that described in the following claims. {9749593: } 22

Claims

CLAIMS What is claimed is:

1. A piezoelectric mechanochemical decontamination system, comprising: a piezoelectric material; an impact medium; a dynamic impact device comprising a receiving chamber; wherein the receiving chamber is configured to receive the piezoelectric material, the impact medium, and a PFAS-contaminated substance comprising solid- and / or semi- solid-state PFAS; and wherein the dynamic impact device is configured to cause the impact medium to collide with the piezoelectric material to thereby cause a piezoelectric reaction that converts one-hundred percent of fluorine included in the PFAS-contaminated substance to fluoride and thereby convert the PFAS-contaminated substance to a decontaminated substance that is environmentally safe for disposal.

2. The system of claim 1, wherein the piezoelectric material is present at a molar ratio of at least 5:1 compared to the fluorine.

3. The system of claim 1, wherein the piezoelectric material comprises boron nitride.

4. The system of claim 1, wherein the impact medium comprises at least one of stainless steel or zirconium.

5. The system of claim 1, wherein the dynamic impact device is a planetary ball mill device, a tumbler mill device, an attritor mill device, or a vibratory ball mill device.

6. The system of claim 1, wherein the dynamic impact device is a jet mill device, a disc mill device, or a rod mill device. {9749593: } 237. The system of claim 1, wherein the impact medium comprises a geometric structure; the geometric structure comprises: a pin; a disc; a triangle; a cylinder; a rectangle; and a rod.

8. The system of claim 1, wherein the piezoelectric material comprises at least one of: strontium titanate; and lead titanate.

9. The system of claim 1, wherein the PFAS-contaminated substance comprises at least one of: a solid; wastewater; and a liquid concentrate.

10. The system of claim 9, wherein the solid comprises at least one of a sorbent, a soil, a biosolid, and a sediment.

11. A piezoelectric mechanochemical decontamination method, comprising: combining a piezoelectric material, an impact medium, and a PFAS-contaminated substance in a receiving chamber of a dynamic impact device; and initiating the dynamic impact device to thereby cause the impact medium to collide with the piezoelectric material and thereby cause a piezoelectric reaction that converts one-hundred percent of fluorine included in the PFAS-contaminated substance to fluoride {9749593: } 24and thereby convert the PFAS-contaminated substance to a decontaminated substance that is environmentally safe for disposal.

12. The method of claim 11, further comprising: separating the impact medium from the decontaminated substance prior to disposal of the decontaminated substance.

13. The method of claim 11, wherein the step of initiating the dynamic impact device to thereby cause the impact medium to collide with the piezoelectric material and thereby cause the piezoelectric reaction comprises causing the piezoelectric reaction to occur for a predetermined time period.

14. The method of claim 11, wherein the PFAS-contaminated substance comprises fluorine; and the step of combining the piezoelectric material, the impact medium, and the PFAS-contaminated substance in the receiving chamber comprises combining the piezoelectric material at a molar ratio of at least 5:1 compared to the fluorine.

15. The method of claim 11, wherein the piezoelectric material comprises boron nitride.

16. The method of claim 11, wherein the impact medium comprises at least one of stainless steel or zirconium.

17. The method of claim 11, wherein the dynamic impact device is a planetary ball mill device, a tumbler mill device, an attritor mill device, or a vibratory ball mill device.

18. The method of claim 11, wherein the dynamic impact device is a jet mill device, a disc mill device, or a rod mill device.

19. The method of claim 11, wherein {9749593: } 25the impact medium comprises a geometric structure; the geometric structure comprises: a pin; a disc; a triangle; a cylinder; a rectangle; and a rod.

20. The method of claim 11, wherein the PFAS-contaminated substance comprises at least one of: a solid; wastewater; and a liquid concentrate. {9749593: } 26

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