Process for preparing fluorinated species

Abstract

The present invention relates to processes for preparing a fluorinated species, as well as to the fluorinated species resulting therefrom. The present invention also relates to the use of said fluorinated species as fluorinating agents.

Description

PROCESS FOR PREPARING FLUORINATED SPECIES INTRODUCTION

[0001] The present invention relates to processes for preparing a fluorinated species, as well as to the fluorinated species resulting therefrom. The present invention also relates to the use of said fluorinated species as fluorinating agents. BACKGROUND OF THE INVENTION

[0002] Since the 1940s, anthropogenic per- and polyfluoroalkyl substances (PFAS) have been produced on a large scale for use in many industry branches. In addition to applications such as textile impregnation and fire-fighting foams, PFAS are components of consumer products such as food packaging, cooking ware materials and artificial turf.

[0003] Structurally, PFAS feature multiple carbon-fluorine (C^F) bonds that give them unique surface properties, as well as their resistance to biological or chemical degradation (1). Today, environmental persistence and bioaccumulation has resulted in global PFAS contamination in drinking water, livestock and agricultural products, with evidence of negative impacts on human health upon chronic exposure (2-5). This state of play requires immediate action with the development of PFAS-removal approaches (6-8) combined with the destruction of the resulting PFAS-contaminated waste streams (9-13).

[0004] Up until now, PFAS degradation methods have included advanced oxidation and reduction processes (14), mechanical and base-assisted destruction (15-21), as well as numerous alternative protocols such as incineration (22) and microbial treatment (23). More recently, milder methods have been deployed, including low temperature mineralization in solution (24) or in the solid-state (25, 26). Photochemically triggered defluorination has also been reported (27, 28).

[0005] In spite of this, and with safety and circular chemistry in mind, a mild method that harvests the fluorine content of PFAS for the production of critically-needed fluorochemicals is still desired. Harvesting the fluorine content of PFAS could mean that pharmaceuticals, which are typically prepared using the increasingly sparse mineral fluorspar (CaF2), may be prepared using waste PFAS.

[0006] The present invention was devised with the foregoing in mind.

[0007] The project leading to this application has received funding from the European Research Council (ERC) under the European Union^s Horizon 2020 research and innovation programme (grant agreement No 832994). SUMMARY OF THE INVENTION

[0008] In some aspects, described herein are methods or processes of synthesizing an organofluorine-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise providing an organofluorine. In some embodiments, the methods or processes comprise providing an activator. In some embodiments, the methods or processes comprise combining the organofluorine with the activator to yield the organofluorine-derived fluorinated inorganic salt.

[0009] In some aspects, methods or processes described herein comprise synthesizing a fluorinated compound. In some embodiments, the methods or processes comprise combining an organofluorine with an activator to yield an organofluorine-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise reacting the organofluorine-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

[0010] In some embodiments, the organofluorine comprises a fluoropolymer and / or a per- or poly- fluorinated alkyl substance (PFAS). In some embodiments, the organofluorine comprises an industrial waste-product and / or an environmental contaminant. In some embodiments, the organofluorine comprises a mixture of two or more different fluorinated polymers. In some embodiments, the organofluorine comprises at least two different fluorinated polymers. In some embodiments, the organofluorine comprises at least three different fluorinated polymers. In some embodiments, the organofluorine comprises at least four different fluorinated polymers.

[0011] In some embodiments, the organofluorine-derived fluorinated inorganic salt comprises a perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt, a polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt,a polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt, a fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt, an ethylene tetrafluoroethylene (ETFE)-derived fluorinated inorganic salt, a perfluorooctanoic acid (PFOA)-derived fluorinated inorganic salt, and / or a perfluorooctane sulfonic acid (PFOS)-derived fluorinate inorganic salt.

[0012] In some aspects, methods or processes described herein comprise synthesizing a perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise providing a perfluoroalkoxy alkane (PFA). In some embodiments, the methods or processes comprise providing an activator. In some embodiments, the methods or processes comprise combining the perfluoroalkoxy alkane (PFA) with the activator to yield the perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt.

[0013] In some aspects, methods or processes described herein comprise synthesizing a fluorinated compound from PFA. In some embodiments, the methods or processes comprise combining a perfluoroalkoxy alkane (PFA) with an activator. In some embodiments, the methodsor processes comprise reacting the perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

[0014] In some aspects, methods or processes described herein comprise synthesizing a polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise providing a polytetrafluoroethylene (PTFE). In some embodiments, the methods or processes comprise providing an activator. In some embodiments, the methods or processes comprise combining the polytetrafluoroethylene (PTFE) with the activator to yield the polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt.

[0015] In some embodiments, methods or processes described herein comprise synthesizing a fluorinated compound from PTFE. In some embodiments, the methods or processes comprise combining a polytetrafluoroethylene (PTFE) with an activator. In some embodiments, the methods or processes comprise reacting the polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

[0016] In some embodiments, methods or processes described herein comprise synthesizing a fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise providing a fluorinated ethylene propylene (FEP). In some embodiments, the methods or processes comprise providing an activator. In some embodiments, the methods or processes comprise combining the fluorinated ethylene propylene (FEP) with the activator to yield the fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt.

[0017] In some embodiments, the methods or processes comprise synthesizing a fluorinated compound from FEP. In some embodiments, the methods or processes comprise combining a fluorinated ethylene propylene (FEP) with an activator. In some embodiments, the methods or processes comprise reacting the fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

[0018] In some embodiments, methods or processes described herein comprise synthesizing a polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise providing a polyvinylidene difluoride (PVDF). In some embodiments, the methods or processes comprise providing an activator. In some embodiments, the methods or processes comprise combining the polyvinylidene difluoride (PVDF) with the activator to yield the polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt.

[0019] In some embodiments, methods or processes described herein comprise synthesizing a fluorinated compound from PVDF. In some embodiments, the methods or processes comprise combining a polyvinylidene difluoride (PVDF) with an activator. In some embodiments, the methods or processes comprise reacting the polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

[0020] In some embodiments, the activator comprises a strong base. In some embodiments, the strong base comprises LiOH, NaOH, KOH, and / or CsOH. In some embodiments, the activator is NaOH or KOH. In some embodiments, the activator is NaOH. In some embodiments, the activator is KOH. In some embodiments, the activator is SiO2.

[0021] In some embodiments, any of the methods or processes described herein may comprise activating the activator by application of mechanical force during the combining and / or reacting.

[0022] In some embodiments, the mechanical force is applied at least in part using a ball mill, a resonant acoustic mixer, a pestle and mortar, a high-shear mixing system, and / or a twin screw extruder.

[0023] In some embodiments, the organofluorine is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP, PFOA, PFOS or PP-PTFE.

[0024] In some embodiments, for each C-F bond present in the organofluorine, 0.25-2.5 equivalents of the activator are combined with 1 equivalent of the organofluorine.

[0025] In some embodiments, for each C-F bond present in the per of polyfluoroalkyl compound, 1-1.4 equivalents of the activator are combined with 1 equivalent of the organofluorine.

[0026] In some embodiments, the organofluorine is or comprises an industrial waste-product.

[0027] In some embodiments, the organofluorine-derived fluorinated inorganic salt is or comprises an alkali metal fluoride. In some embodiments, the alkali metal fluoride comprise LiF, NaF, and / or KF. In some embodiments, the alkali metal fluoride is LiF. In some embodiments, the alkali metal fluoride is NaF. In some embodiments, the alkali metal fluoride is KF.

[0028] In some embodiments, the organofluorine-derived fluorinated inorganic salt is comprised in a resulting mixture which comprises at least 1 ppm of the organofluorine.

[0029] In some embodiments, any method or process described herein may comprise fluorinating a reagent comprising at least one leaving group using the organofluorine-derived fluorinated inorganic salt to yield a fluorinated product.

[0030] In some embodiments, the fluorinated product comprises an organo-fluorine compound which is different from the organofluorine from which the fluorinated inorganic salt was derived.

[0031] In some embodiments, the fluorinated product comprises a recycled or remanufactured product of the organofluorine from which the fluorinated inorganic salt was derived.

[0032] In some embodiments, the fluorinated product comprises an alkyl fluoride and / or an aromatic fluoride.

[0033] In some embodiments, the organofluorine is a commercial grade product which was produced in excess.

[0034] In some embodiments, the organofluorine and / or the activator are comprised in a solution and / or a liquid suspension when the mechanical force is applied. In some embodiments, the mechanical force is applied using a sonicator.

[0035] Any activator described herein may be used alone or in combination with other activators. Any activator or combination of activators described herein may in the performance of any of the methods or processes described herein.

[0036] Activators described herein may independently function as a nucleophile (e.g., a strong nucleophile having a nucleophilicity index for attack on a C-F bond of 20 or more) and / or as a base (e.g., a strong base).

[0037] In some cases, activators described herein may cleave a C-F bond with the assistance of mechanical energy. In some cases, activators described herein may cleave a C-F bond without the assistance of mechanical energy.

[0038] According to a first aspect of the present invention, there is provided a process comprising the step of pulverising together a per- or polyfluoroalkyl compound and an activator, wherein the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal.

[0039] The process of the first aspect of the present invention may result in a mixture comprising at least one fluorinated species.

[0040] According to a second aspect of the present invention, there is provided a process in accordance with the first aspect of the present invention, wherein the process further comprises the step of using the mixture, or the at least one fluorinated species contained therein, as a fluorinating agent.

[0041] According to a third aspect of the present invention, there is a provided a mixture comprising one or more fluorinated species obtainable by the process of the second aspect of the present invention.

[0042] According to a fourth aspect of the present invention, there is provided a use of the mixture as defined in the third aspect of the present invention as a fluorinating agent.

[0043] A fluorinating agent can be used to introduce fluorine (e.g., a fluorine atom) into a compound (e.g., an organic compound).

[0044] In some aspects, described herein are processes comprising the step of pulverising together a per- or polyfluoroalkyl compound and an activator, wherein the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal. In some embodiments, the step of pulverising is conducted in a ball mill, a resonant acoustic mixer, apestle and mortar or a twin screw extruder. In some embodiments, the pulverising step results in the degradation of C-F bonds.

[0045] In some embodiments, the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I): , wherein R1is H, halo, (1-3C)haloalkyl or (1-3C)haloalkoxy. In some embodiments,Cl, CH2F, CF2H, CF3 or OCF3. In some embodiments, the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ib):wherein R1, R2 and R3 are each independently selected from H, halo, (1- 3C)haloalkyl and (1-3C)haloalkoxy. In some embodiments, R1, R2 and R3 are each independently selected from H, F, Cl and CF3.

[0046] In some embodiments, the per- or polyfluoroalkyl compound comprises a moiety having any one of the following structures:

[0047] In some embodiments, the per- or polyfluoroalkyl compound is a polymer. In some embodiments, the polymer comprises a monomeric repeating unit having the structure of Formula (IIb):wherein R1, R2 and R3 are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy.

[0048] In some embodiments, (i) R1, R2 and R3 are F; (ii) R1 is F, and R2 and R3 are H; (iii) R1 is F, R2is F and R3is Cl; (iv) R1is CF3, and R2and R3are F; or (v) R1, R2and R3are H.

[0049] In some embodiments, the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP or PP-PTFE.

[0050] In some embodiments, the activator is: (i) a phosphate, monosulfate, carbonate, oxalate, silicate or oxide of a group I metal; or (ii) a carbonate or silicate of a group II metal.

[0051] In some embodiments, the activator is selected from: (i) M2HPO4, MH2PO4, M3PO4, MPO3, M2PO3F, M4P2O7, M5P3O10, M2SO4, M2CO3, M2C2O4, MHCO3, M2SiO3 and M2O, wherein M is a group I metal; or (ii) M^HPO4, M^(H2PO4)2, M^CO3and M^2SiO4, wherein M^ is a group II metal.

[0052] In some embodiments, the activator is selected from: (i) M2HPO4, M3PO4, M4P2O7, M2CO3, M2SiO3 and M2O, wherein M is a group I metal; or (ii) M^2SiO4, wherein M^ is a group II metal.

[0053] In some embodiments, the group I metal (i.e., M) Na or K. In some embodiments, the group II metal (i.e., M^) is Ca. In some embodiments, the activator is K2HPO4, KH2PO4, K3PO4, Na3PO4, Li3PO4, KPO3, K4P2O7, Na4P2O7 K5P3O10, NaPO3, CaHPO4, Ca(H2PO4)2, K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4, Na2CO3, K2PO3F, KHCO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O. In some embodiments, the activator is K3PO4, Na3PO4, K4P2O7, K2CO3, K2SiO3, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O. In some embodiments, the activator is K3PO4or K4P2O7.

[0054] In some embodiments, for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-2.5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. In some embodiments, for each C-F bond present in the per of polyfluoroalkyl compound, 1-1.4 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound.

[0055] In some embodiments, processes and methods described herein may each independently comprises the following steps: pulverising together a per- or polyfluoroalkyl compound and an activator, wherein the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal (e.g., a phosphate of a group I or group II metal); forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together; and pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts.

[0056] In some embodiments, the step of forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together comprises extracting an insoluble activator salt residue from the reaction mixture. In some embodiments, the insoluble activator salt residue is treated with H2O and KOH to form a mixture of recovered activator salts. In some embodiments, the activator is a phosphate of a group I metal and the mixture of recovered activator salts comprises phosphates of the group I metal.

[0057] In some embodiments, the activator is K3PO4and the mixture of recovered activator salts comprises K3PO4 and / or K4P2O7. In some embodiments, the step of pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts results in a mixture comprising at least one fluorinated species. In some embodiments, the step of pulverising together the per- or polyfluoroalkyl compound and the activator results in a mixture comprising at least one fluorinated species.

[0058] In some aspects, described herein are mixtures comprising one or more fluorinated species obtainable by any of the processes or methods described herein. In some embodiments, such mixtures may be used as a fluorinating agent.

[0059] In some aspects, described herein are methods or processes of synthesizing an organofluorine-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise providing an organofluorine; providing an activator; and combining the organofluorine with the activator to yield the organofluorine-derived fluorinated inorganic salt.

[0060] In some aspects, described herein are methods or processes of synthesizing a fluorinated compound. In some embodiments, the methods or processes comprise combining an organofluorine with an activator to yield an organofluorine-derived fluorinated inorganic salt; and reacting the organofluorine-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

[0061] In some embodiments, the organofluorine comprises a fluoropolymer and / or a per- or poly- fluorinated alkyl substance (PFAS). In some embodiments, the organofluorine-derived fluorinated inorganic salt comprises a perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt, a polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt,a polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt, a fluorinated ethylene propylene (FEP)- derived fluorinated inorganic salt, an ethylene tetrafluoroethylene (ETFE)-derived fluorinated inorganic salt, a perfluorooctanoic acid (PFOA)-derived fluorinated inorganic salt, and / or a perfluorooctane sulfonic acid (PFOS)-derived fluorinate inorganic salt.

[0062] In some aspects, described herein are methods or processes of synthesizing a perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise providing a perfluoroalkoxy alkane (PFA); providing an activator; and combining the perfluoroalkoxy alkane (PFA) with the activator to yield the perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt.

[0063] In some aspects, described herein are methods or processes of synthesizing a fluorinated compound. In some embodiments, the methods or processes comprise combining a perfluoroalkoxy alkane (PFA) with an activator; and reacting the perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

[0064] In some aspects, described herein are methods or processes of synthesizing a polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise providing a polytetrafluoroethylene (PTFE); providing an activator; and combining the polytetrafluoroethylene (PTFE) with the activator to yield the polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt.

[0065] In some embodiments, any of the methods or processes described herein can comprise combining a polytetrafluoroethylene (PTFE) with an activator; and reacting the polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield a fluorinated compound.

[0066] In some aspects, described herein are methods or processes of synthesizing a fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt. In some embodiments, the methods or processes comprise providing a fluorinated ethylene propylene (FEP); providing an activator; and combining the fluorinated ethylene propylene (FEP) with the activator to yield the fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt.

[0067] In some embodiments, any of the methods or processes described herein can comprise combining a fluorinated ethylene propylene (FEP)with an activator; and reacting the fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

[0068] In some embodiments, a method of synthesizing a polyvinylidene difluoride (PVDF)- derived fluorinated inorganic salt, the method comprising: providing a polyvinylidene difluoride (PVDF); providing an activator; and combining the polyvinylidene difluoride (PVDF) with the activator to yield the polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt.

[0069] In some embodiments, any of the methods or processes described herein can comprise combining a polyvinylidene difluoride (PVDF) with an activator; and reacting the polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

[0070] In some embodiments, the activator comprises a strong base. In some embodiments, the strong base comprises LiOH, NaOH, KOH, and / or CsOH. In some embodiments, the activator is NaOH or KOH. In some embodiments, the activator is NaOH. In some embodiments, the activator is KOH.

[0071] In some embodiments, any of the methods or processes described herein comprise activating the activator by application of mechanical force during the combining and / or reacting.In some embodiments, the mechanical force is applied at least in part using a ball mill, a resonant acoustic mixer, a pestle and mortar, a high-shear mixing system, and / or a twin screw extruder.

[0072] In some embodiments of any of the methods or processes described herein, the organofluorine is or comprises an industrial waste-product. In some embodiments, the organofluorine-derived fluorinated inorganic salt is or comprises an alkali metal fluoride. In some embodiments, the alkali metal fluoride comprise LiF, NaF, and / or KF. In some embodiments, the alkali metal fluoride is LiF. In some embodiment, the alkali metal fluoride is NaF. In some embodiments, the alkali metal fluoride is KF.

[0073] In some embodiments, the organofluorine-derived fluorinated inorganic salt is comprised in a resulting mixture which comprises at least 1 ppm of the organofluorine.

[0074] In some embodiments, any of the methods or processes described herein can comprise fluorinating a reagent comprising at least one leaving group using the organofluorine-derived fluorinated inorganic salt to yield a fluorinated product. In some embodiments, the fluorinated product comprises an organo-fluorine compound which is different from the organofluorine from which the fluorinated inorganic salt was derived.

[0075] In some embodiments, the fluorinated product comprises a recycled or remanufactured product of the organofluorine from which the fluorinated inorganic salt was derived. In some embodiments, the fluorinated product comprises an alkyl fluoride and / or an aromatic fluoride. In some embodiments, the organofluorine is a commercial grade product produced in excess. In some embodiments, the organofluorine and / or the activator are comprised in a solution and / or a liquid suspension when the mechanical force is applied. In some embodiments, the mechanical force is applied using a sonicator.

[0076] In some embodiments, the organofluorine comprises a mixture of two or more different fluorinated polymers (e.g., wherein the oranofluorine comprises at least two, at least three, or at least four different fluorinated polymers). DETAILED DESCRIPTION OF THE INVENTION

[0077] Throughout the entirety of the description and claims of this specification, where subject matter is described herein using the term ^comprise^ (or ^comprises^ or ^comprising^), the same subject matter instead described using the term ^consist of^ (or ^consists of^ or ^consisting of^) or ^consist essentially of^ (or ^consists essentially of^ or ^consisting essentially of^) is also contemplated.

[0078] Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used,the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0079] Features described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. The invention is not restricted to the details of any of the specific embodiments recited herein. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0080] As described hereinbefore, the first aspect of the present invention provides a process comprising the step of pulverising together a per- or polyfluoroalkyl compound and an activator, wherein the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal.

[0081] Through rigorous investigations, the inventors have devised a regenerative and operationally simple activator-enabled mechanochemical process to effectively and efficiently degrade a variety of PFAS (e.g., PFAS derived from consumer items and pollutants), including polymeric materials such as poly(tetrafluoroethylene) (PTFE) and poly(vinylidene fluoride) (PVDF), as well as harmful non-polymeric perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), into fluorine sources at qualitative yield. The inventors have found that these fluorine sources allow for the production of high-value fluorochemicals in an analogous manner to commercial fluorine sources. This mild process therefore demonstrates that PFAS can be considered as a viable fluorine source for fluorochemical production and offers a new approach towards harmful PFAS waste management. Thus, the process of the present invention also simultaneously provides a solution to the shortage of fluorspar, a critical mineral for the production of fluorine-containing pharmaceuticals, agrochemicals and materials such as lithium-ion batteries.

[0082] The process of the invention typically involves reacting a per- or polyfluoroalkyl compound and an activator in the solid state using a high-energy mixing technique, such as one that is sufficient to mechanically reduce the particle size of (e.g., crush) the reactants and bring them into contact with one another in such a manner that causes a chemical reaction to occur, thereby changing their chemical composition. Pulverising together the reactants achieves this objective. It will, however, be appreciated that synonymous high-energy mixing techniques resulting in a chemical reaction between the reactants and a reduction in their particle size (and / oran increased surface area to volume ratio of the reactants), such as crushing together, grinding together, milling together, mashing together, macerating together and the like, are embraced by the pulverising step in the process of the present invention.

[0083] The step of pulverising may be a mechanochemical process and / or may be conducted under mechanochemical conditions. Mechanochemistry is a developing area of chemical synthesis and is widely understood to refer to chemical transformations that are initiated by and / or sustained by the application of a mechanical stress to one or more solid reactants.

[0084] The step of pulverising may be conducted in a ball mill, a pestle and mortar or a twin- screw extruder (TSE). Other techniques and apparatuses suitable for carrying out the pulverising step will be familiar to one skilled in the art, e.g. those skilled in the art of mechanochemistry, including an ultrasonic bath, a mechanical press and / or resonant acoustic mixing (RAM).

[0085] In a particular embodiment, the step of pulverising is conducted in a ball mill. Exemplary ball mills include a planetary ball mill, a vibratory ball mill, an attritor ball mill or a tumbling ball mill. Most suitably, the ball mill is a vibratory ball mill.

[0086] The person skilled in the art of ball milling will be able to select appropriate conditions, including ball size and weight, vessel size and frequency. For example, a stainless steel vessel and one or more stainless steel balls may be used. Alternatively, a zirconia vessel and one or more zirconia balls may be used. A ball, or balls, (each) weighing 2-20 g (e.g., 3 g, 4 g, 7 g or 16 g) may, for example, be used.

[0087] The step of pulverising may be carried out for any suitable period of time. For example, the step of pulverising may be carried out for 0.5 ^ 12 hours. Suitably, the step of pulverising is carried out for 0.5 ^ 6 hours. Most suitably, the step of pulverising is carried out for 1 ^ 5 hours.

[0088] Suitably, the step of pulverising is conducted in a ball mill and is carried out for 0.5 ^ 12 hours. More suitably, the step of pulverising is conducted in a ball mill and is carried out for 0.5 ^ 6 hours.

[0089] In some embodiments, the step of pulverising comprises ball milling the reactants together at a frequency of 0.5 ^ 80 Hz. More suitably, the step of pulverising comprises ball milling the reactants together at a frequency of 5 ^ 65 Hz. Even more suitably, the step of pulverising comprises ball milling the reactants together at a frequency of 15 ^ 45 Hz. Most suitably, the step of pulverising comprises ball milling the reactants together at a frequency of 20 ^ 40 Hz (e.g., 28 ^ 38 Hz).

[0090] Suitably, the step of pulverising comprises ball milling the reactants together at a frequency of 0.5 ^ 80 Hz for 0.5 ^ 12 hours. More suitably, the step of pulverising comprises ball milling the reactants together at a frequency of 20 ^ 40 Hz (e.g., 28 ^ 38 Hz) for 0.5 ^ 6 hours.

[0091] The step of pulverising is typically conducted in the solid state. In its simplest sense, the step of pulverising is conducted in the absence (or substantial absence) of any solvent. However, the use of some solvent is known to offer advantages in some solid state (e.g., mechanochemical) reactions. Examples of such techniques include solvent-assisted mechanochemistry (sometimes termed liquid-assisted mechanochemistry, e.g., liquid-assisted grinding). Suitably, the step of pulverising is conducted in less than 500 wt% of a solvent relative to the combined mass of the reactants. Thus, if 1 g each of the per- or polyfluoroalkyl compound and the activator are used, the step of pulverising may be conducted in less than 10 g of solvent. More suitably, the step of pulverising is conducted in less than 200 wt% of a solvent relative to the combined mass of the reactants. Even more suitably, the step of pulverising is conducted in less than 50 wt% of a solvent relative to the combined mass of the reactants. Yet more suitably, the step of pulverising is conducted in less than 10 wt% of a solvent relative to the combined mass of the reactants. Most suitably, the step of pulverising is conducted in the absence (or substantial absence) of any solvent. It may be that >50wt% of the per- or polyfluoroalkyl compound, the activator and any reaction products derived therefrom, remain in the solid state throughout the process. Suitably, >70wt% of the per- or polyfluoroalkyl compound, the activator and any reaction products derived therefrom, remain in the solid state throughout the process. More suitably, >90wt% of the per- or polyfluoroalkyl compound, the activator and any reaction products derived therefrom, remain in the solid state throughout the process. Even more suitably, >95wt% of the per- or polyfluoroalkyl compound, the activator and any reaction products derived therefrom, remain in the solid state throughout the process. The step of pulverising may therefore be described as being conducted in the solid state.

[0092] In a particular embodiment, the step of pulverising is conducted in the absence (or substantial absence) of any solvent. Suitably, the step of pulverising involves pulverising together the per- or polyfluoroalkyl compound and the activator in a ball mill (i.e., ball milling the per- or polyfluoroalkyl compound and the activator).

[0093] It may be that in the process of the invention, the step of pulverising a per- or polyfluoroalkyl compound and an activator results in the degradation of C-F bonds (e.g., in the per- or polyfluoroalkyl compound). Suitably, the process is for the degradation of one or more C^ F bonds.

[0094] The term ^per- or polyfluoroalkyl compound^ will be understood to mean compounds comprising carbon-fluorine (C^F) bonds. The per- or polyfluoroalkyl compound may be polymeric (e.g., polytetrafluoroethylene (PTFE)) or non-polymeric (e.g., Perfluorooctanoic acid (PFOA)). The per- or polyfluoroalkyl compound may be fully fluorinated (e.g., PTFE) or partially fluorinated (e.g., polyvinylidene difluoride (PVDF)). The per- or polyfluoroalkyl compounds may be referredto as per- and polyfluoroalkyl substances (PFAS) throughout the entirety of the specification. PFAS are well known in the art and will be familiar to a skilled person.

[0095] The per- or polyfluoroalkyl compound may comprise a moiety having the structure of Formula (I):wherein R1is H, halo, (1-3C)haloalkyl or (1-3C)haloalkoxy.

[0096] Suitably, R1 is H, F, Cl, Br, (1-2C)haloalkyl or (1-2C)haloalkoxy. More suitably, R1 is H, F, Cl, CH2F, CF2H, CF3or OCF3. Most suitably, R1is H, F, Cl or CF3.

[0097] The per- or polyfluoroalkyl compound may comprise a moiety having the structure of Formula (Ia):wherein R, R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl or (1- 3C)haloalkoxy, with the proviso that at least one of R, R1, R2 and R3 is F.

[0098] Suitably, R, R1, R2and R3are each independently selected from H, F, Cl, Br, (1- 2C)haloalkyl and (1-2C)haloalkoxy. More suitably, R, R1, R2 and R3 are each independently selected from H, F, Cl, CH2F, CF2H, CF3and OCF3. Most suitably, R, R1, R2and R3are each independently selected from H, F, Cl and CF3.

[0099] The per- or polyfluoroalkyl compound may comprise a moiety having the structure of Formula (Ib):wherein R1, R2 and R3 are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy.

[0100] Suitably, R1, R2and R3are each independently selected from H, F, Cl, Br, (1- 2C)haloalkyl and (1-2C)haloalkoxy. More suitably, R1, R2 and R3 are each independently selected from H, F, Cl, CH2F, CF2H, CF3and OCF3. Most suitably, R1, R2and R3are each independently selected from H, F, Cl and CF3.

[0101] In a particular embodiment: (i) R1is H, F or CF3; and (ii) R2 and R3 are each independently selected from H, F and Cl.

[0102] In a particular embodiment: (i) R1, R2 and R3 are F; (ii) R1 is F, and R2 and R3 are H; (iii) R1is F, R2is F and R3is Cl; (iv) R1is CF3, and R2and R3are F; or (v) R1, R2 and R3 are H.

[0103] The per- or polyfluoroalkyl compound may comprise a moiety having any one of the following structures:

[0104] Suitably, the per- or polyfluoroalkyl compound comprises a moiety having the following structure:.

[0105] The per- or polyfluoroalkyl compound may comprise a terminal end group, X. In such embodiments, the per- or polyfluoroalkyl compound may comprise a moiety having the structure of Formula (Ic):wherein X is a terminal end group and R, R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl or (1-3C)haloalkoxy, with the proviso that at least one of R, R1, R2 and R3 is F.

[0106] Suitably, R, R1, R2 and R3 are each independently selected from H, F, Cl, Br, (1- 2C)haloalkyl and (1-2C)haloalkoxy. More suitably, R, R1, R2and R3are each independently selected from H, F, Cl, CH2F, CF2H, CF3 and OCF3. Most suitably, R, R1, R2 and R3 are each independently selected from H, F, Cl and CF3.

[0107] The per- or polyfluoroalkyl compound may comprise a moiety having the structure of Formula (Id):wherein X is a terminal end group and R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl and (1-3C)haloalkoxy.

[0108] Suitably, R1, R2and R3are each independently selected from H, F, Cl, Br, (1- 2C)haloalkyl and (1-2C)haloalkoxy. More suitably, R1, R2 and R3 are each independently selected from H, F, Cl, CH2F, CF2H, CF3 and OCF3. Most suitably, R1, R2 and R3 are each independently selected from H, F, Cl and CF3.

[0109] It will be appreciated that terminal end group, X, is intended to cap (i.e., terminate) the per- or polyfluoroalkyl compound. X may be any suitable terminal end group, meaning that X can be a wide range of groups and these will all be familiar to a person skilled in the art. For example, X may be -Ra, -(CH2)Y-Ra, -ORa, -C(O)Ra, -COORa, -C(O)NRa, -SO3Ra, -SO3K, -SO2NRaRb, - PO3RaRb, -PO2Ra or -SO2Ra, where Y is an integer selected from 1 to 8, and Ra and Rb are each independently selected from H, (1-6C)alkyl or (1-6C)haloalkyl. Suitably, Y is an integer selected from 1 to 6, and Raand Rbare each independently selected from H, (1-4C)alkyl or (1- 4C)haloalkyl. More suitably, Y is an integer selected from 1 to 4, and Ra and Rb are each independently selected from H, (1-2C)alkyl or (1-2C)haloalky. More suitably, Y is an integer selected from 1 or 2, and Ra and Rb are each independently selected from H, CH3 or CF3.

[0110] In some embodiments, X is a group selected from -H, -CH3, -CF3, -OH, -OCH3, -OCF3, -CH2OH, -CH2CH2OH, -COOH, -C(O)NH, -C(O)NMe, -SO3H, -SO3K, -SO3Me, -SO2NH2, - SO2NMe2, -PO3H2, -PO3Me2, -PO2H, -PO2Me, -SO2H, -SO2Me, -C(O)NH-(CH2)3-NMe3+or - CH2CH2-SO2NH-(CH2)3-NMe2+-CH2-COO-. Suitably, X is a group selected from -H, -CH3, -CF3, - OH, -OCH3, -OCF3, -CH2CH2OH, -COOH, -C(O)NH, -SO3H, -SO3K, -SO2NH2, -PO3H2, -PO2H or-SO2H. More suitably, X is a group selected from -H, -CF3, -OH, -CH2CH2OH, -COOH, -SO3H, - SO3K, -PO3H2, -PO2H or -SO2H.

[0111] The per- or polyfluoroalkyl compound may be a polymer. In such embodiments, the polymer may comprise a monomeric repeating unit having the structure of Formula (IIa):wherein R, R1, R2 and R3 are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy, with the proviso that at least one of R, R1, R2and R3is F.

[0112] Suitably, R, R1, R2and R3are each independently selected from H, F, Cl, Br, (1- 2C)haloalkyl and (1-2C)haloalkoxy. More suitably, R, R1, R2and R3are each independently selected from H, F, Cl, CH2F, CF2H, CF3 and OCF3. Most suitably, R, R1, R2 and R3 are each independently selected from H, F, Cl and CF3.

[0113] The polymer may comprise a monomeric repeating unit having the structure of Formula (IIb):wherein R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy.

[0114] Suitably, R1, R2 and R3 are each independently selected from H, F, Cl, Br, (1- 2C)haloalkyl and (1-2C)haloalkoxy. More suitably, R1, R2 and R3 are each independently selected from H, F, Cl, CH2F, CF2H, CF3and OCF3. Most suitably, R1, R2and R3are each independently selected from H, F, Cl and CF3.

[0115] It may be that R1, R2and R3are all identical. It may be that two of R1, R2and R3are identical. It may be that R1, R2 and R3 are all different.

[0116] In a particular embodiment: (i) R1is H, F or CF3; and (ii) R2and R3are each independently selected from H, F and Cl.

[0117] In a particular embodiment: (i) R1, R2and R3are F; (ii) R1is F, and R2and R3are H; (iii) R1 is F, R2 is F and R3 is Cl; (iv) R1 is CF3, and R2 and R3 are F; or (v) R1, R2 and R3 are H.

[0118] The per- or polyfluoroalkyl compound may be a polymer comprising a monomeric repeating unit selected from:

[0119] Suitably, the per- or polyfluoroalkyl compound is a polymer comprising the following monomeric repeating unit:.

[0120] The polymer may terminate with terminal end group, X. Suitably, X has any one of the definitions described herein.

[0121] In any of Formula Ia, Ic or IIa, all of R, R1, R2and R3may be identical. Alternatively, three of R, R1, R2and R3may be identical. Alternatively two of R, R1, R2and R3may be identical. Alternatively, R, R1, R2 and R3 may all be different. In these embodiments, at least one of R, R1, R2and R3is F.

[0122] In any of Formula Ib, Id or IIb, all of R1, R2 and R3 may be identical. Alternatively, two of R1, R2and R3may be identical. Alternatively, R1, R2and R3may all be different.

[0123] In embodiments wherein the per- or polyfluoroalkyl compound is a polymer, the polymer may comprise at least 10 monomeric repeating units. Suitably, the polymer comprises at least 20 monomeric repeating units. More suitably, the polymer comprises at least 50 monomeric repeating units. More suitably, the polymer comprises at least 100 monomeric repeating units. Suitably, the monomeric repeating unit has the structure of Formula (IIa) or Formula (IIb).

[0124] In embodiments wherein the per- or polyfluoroalkyl compound is a polymer, the polymer may be a homopolymer. Alternatively, the polymer may be a copolymer (e.g., an alternating copolymer, a random copolymer, a block copolymer or a graft copolymer).

[0125] The per- or polyfluoroalkyl compound may be a perfluoroalkyl carboxylic acid, a perfluoroalkyl sulfonic acid, a perfluoroalkyl phosphonic acid, a perfluoroalkyl phosphinic acid, a perfluoroalkane sulfonyl fluoride, a fluorotelomer, a fluoropolymer or a perfluoropolyther.

[0126] In some embodiments, the per- or polyfluoroalkyl compound is poly(tetrafluoroethylene) (PTFE) (e.g., PTFE powder, PTFE tape or PTFE seal), poly(vinylidene fluoride) (PVDF) (e.g., PVDF fittings), poly(chlorotrifluoroethylene) (PCTFE), ethylene-chlorotrifluoroethylene (ECTFE), poly(ethene-co-tetrafluoroethene) (ETFE) (e.g., ETFE wire), poly(vinylidene fluoride-co- hexafluoropropylene) (PVDF-HFP), poly(vinyl fluoride) (PVF), fluorinated ethylene propylene (FEP) (e.g., FEP tubing), poly(propylene)-co-poly(tetrafluoroethylene) (PP-PTFE), perfluorooctanoic acid (PFOA) (e.g., powdered activated carbon (PAC)-adsorbed PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), perfluorooctanesulfonic acid (PFOS), perfluorooctanesulfonamide (PFOSA), potassium perfluorohexanesulfonate (KPFHxS), potassium perfluorobutanesulfonate (KPFBS), a fluorotelomer alcohol (FTOH) (e.g., 4:2 FTOH, 6:2 FTOH, 8:2 FTOH, 10:2 FTOH, 12:FTOH, 6:2 fluorotelomer sulfonamide betaine, granulated activated carbon (GAC)-adsorbed 8:2 FTOH, tridecafluorooctan-1-ol or heptadecafluorodecan- 1-ol), perfluoropentadecane (PFPD), perfluorobutanoic acid (PFBA), perfluoropentanoic acid (PFPeA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorotridecanoic acid (PFTrDA), perfluorotetradecanoic acid (PFTeDA), perfluoropentadecanoic acid (PFPeDA), perfluorohexadecanoic acid (PFHxDA), perfluorobutanesulfonic acid (PFBS), perfluoropentanesulfonic acid (PFPeS), perfluorohexanesulfonic acid (PFHxS), perfluorodecaneslufonic acid (PFDS), perfluorobutylphosphonic acid (PFBPA), perfluorohexaphosphonic acid (PFHxPA), perfluorooctylphosphonic acid (PFOPA), perfluorodecaphosphonic acid (PFDPA), perfluoroalkyl phosphinic acids (PFPiA) (e.g., C4 / C4 PFPiA, C6 / C6 PFPiA, C8 / C8 PFPiA or C6 / C8 PFPiA), perfluorobutane sulfonamide (FBSA), perfluorobutane methylsulfonamide (Me-FBSA), perfluorobutane ethylsulfonamide (Et-FBSA), perfluorooctane sulfonamide (FOSA), perfluorooctane methylsulfonamide (Me-FOSA), perfluorooctane ethylsulfonamide (Et-FOSA), perfluorobutane sulfonamidoethanol (FBSE), perfluorobutane methylsulfonamidoethanol (Me- FBSE), perfluorooctane ethylsulfonamidoethanol (Et-FOSE), perfluorooctane methylsulfonamidoethanol (Me-FOSE), perfluorooctane ethylsulfonamidoethanol (Et-FOSE), a polyfluoroalkyl phosphoric acid diester (diPAPs) (e.g., 6:2 diPAP or 8:2 diPAP), a fluorotelomer phosphonic acid (FTPA) (e.g.6:2 FTPA), a fluorotelomer sulfonic acid (FTSA) (e.g., 6:2 FTSA), a perfluoroalkoxy polymer (PFA) or perfluorotripentylamine (Fluorinert^FC-70). Suitably, the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP, PP-PTFE, PFOA, PFNA, PFDA, PFUnDA, PFDoDA, PFOS, PFOSA, KPFHxS, KPFBS, FTOH, PFPD orFC-70. More suitably, the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP or PP-PTFE. More suitably, the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE or PVDF-HFP. More suitably, the per- or polyfluoroalkyl compound is PTFE.

[0127] Suitably, the step of pulverising is conducted in a ball mill and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the step of pulverising is conducted in a ball mill and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). More suitably, the step of pulverising is conducted in a ball mill and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ib). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0128] Suitably, the step of pulverising is conducted in a ball mill and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the step of pulverising is conducted in a ball mill and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0129] As described hereinbefore, the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal. It is thought that the activator promotes the degradation of a variety of per- and polyfluoroalkyl compounds, thereby allowing the reaction to proceed in milder conditions.

[0130] The activator may be a phosphate (e.g., a monophosphate, a metaphosphate, a pyrophosphate, a triphosphate or a fluorophosphate) of a group I metal. For example, the activator may be a phosphate of lithium, sodium, potassium, rubidium, cesium or francium. Suitably, the activator is a phosphate of lithium, sodium or potassium. More suitably, the activator is a phosphate of sodium or potassium. Even more suitably, the activator is a phosphate of potassium.

[0131] Suitably, the activator is a phosphate of a group I metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is a phosphate of lithium, sodium or potassium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0132] Suitably, the activator is a phosphate of a group I metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is a phosphate of lithium, sodium or potassiumand the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0133] The activator may be a phosphate (e.g., a monophosphate, a metaphosphate, a pyrophosphate, a triphosphate or a fluorophosphate) of a group II metal. For example, the activator may be a phosphate of beryllium, magnesium, calcium, strontium or barium. Suitably, the activator is a phosphate of calcium. In some embodiments, the activator is not a diphosphate of magnesium. In some embodiments, the activator is not a phosphate of magnesium.

[0134] Suitably, the activator is a phosphate of a group II metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is a phosphate of calcium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0135] Suitably, the activator is a phosphate of a group II metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is a phosphate of calcium and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0136] The activator may be a sulfate (e.g., a monosulfate, a pyrosulfate or a persulfate) of a group I metal. For example, the activator may be a sulfate of lithium, sodium, potassium, rubidium, cesium or francium. Suitably, the activator is a sulfate of lithium, sodium or potassium. More suitably, the activator is a sulfate of sodium or potassium. Even more suitably, the activator is a monosulfate of sodium or potassium. Most suitably, the activator is a monosulfate of sodium. In some embodiments, the activator is not a persulfate or pyrosulfate of potassium. In some embodiments, the activator is not a sulfate of potassium.

[0137] In some embodiments, the activator is not a sulfate of a group I metal.

[0138] Suitably, the activator is a sulfate of a group I metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is a monosulfate of sodium or potassium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0139] Suitably, the activator is a sulfate of a group I metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is a monosulfate of sodium or potassium andthe per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0140] The activator may be a sulfate (e.g., a monosulfate, a pyrosulfate or a persulfate) of a group II metal. For example, the activator may be a sulfate of beryllium, magnesium, calcium, strontium or barium. Suitably, the activator is a sulfate of magnesium. In some embodiments, the activator is not a monosulfate of calcium. In some embodiments, the activator is not a sulfate of calcium.

[0141] In some embodiments, the activator is not a sulfate of a group II metal.

[0142] Suitably, the activator is a sulfate of a group II metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is a sulfate of magnesium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0143] Suitably, the activator is a sulfate of a group II metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is a sulfate of magnesium and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0144] The activator may be a carbonate of a group I metal. For example, the activator may be a carbonate of lithium, sodium, potassium, rubidium, cesium or francium. Suitably, the activator is a carbonate of lithium, sodium or potassium. More suitably, the activator is a carbonate of sodium or potassium.

[0145] Suitably, the activator is a carbonate of a group I metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is a carbonate of lithium, sodium or potassium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0146] Suitably, the activator is a carbonate of a group I metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is a carbonate of lithium, sodium or potassium and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0147] The activator may be a carbonate of a group II metal. For example, the activator may be a carbonate of beryllium, magnesium, calcium, strontium or barium. Suitably, the activator is a carbonate of calcium or magnesium.

[0148] Suitably, the activator is a carbonate of a group II metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is a carbonate of calcium or magnesium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0149] Suitably, the activator is a carbonate of a group II metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is a carbonate of calcium or magnesium and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0150] The activator may be an oxalate of a group I metal. For example, the activator may be an oxalate of lithium, sodium, potassium, rubidium, cesium or francium. Suitably, the activator is an oxalate of lithium, sodium or potassium. More suitably, the activator is an oxalate of sodium or potassium.

[0151] Suitably, the activator is an oxalate of a group I metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is an oxalate of lithium, sodium or potassium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0152] Suitably, the activator is an oxalate of a group I metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is an oxalate of lithium, sodium or potassium and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0153] The activator may be an oxalate of a group II metal. For example, the activator may be an oxalate of beryllium, magnesium, calcium, strontium or barium. Suitably, the activator is an oxalate of magnesium. In some embodiments, the activator is not an oxalate of calcium.

[0154] Suitably, the activator is an oxalate of a group II metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is an oxalate of magnesium and the per- or polyfluoroalkyl compound comprises a moiety havingthe structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0155] Suitably, the activator is an oxalate of a group II metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is an oxalate of magnesium and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0156] The activator may be a silicate of a group I metal. For example, the activator may be a silicate of lithium, sodium, potassium, rubidium, cesium or francium. Suitably, the activator is a silicate of lithium, sodium or potassium. More suitably, the activator is a silicate of sodium or potassium.

[0157] Suitably, the activator is a silicate of a group I metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is a silicate of lithium, sodium or potassium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0158] Suitably, the activator is a silicate of a group I metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is a silicate of lithium, sodium or potassium and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0159] The activator may be a silicate of a group II metal. For example, the activator may be a silicate of beryllium, magnesium, calcium, strontium or barium. Suitably, the activator is a silicate of calcium or magnesium. More suitably, the activator is a silicate of calcium.

[0160] Suitably, the activator is a silicate of a group II metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is a silicate of calcium or magnesium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0161] Suitably, the activator is a silicate of a group II metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is a silicate of calcium or magnesium and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having thestructure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0162] The activator may be an oxide of a group I metal. For example, the activator may be an oxide of lithium, sodium, potassium, rubidium, cesium or francium. Suitably, the activator is an oxide of lithium, sodium or potassium. More suitably, the activator is an oxide of lithium or sodium.

[0163] Suitably, the activator is an oxide of a group I metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is an oxide of lithium, sodium or potassium and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0164] Suitably, the activator is an oxide of a group I metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is an oxide of lithium, sodium or potassium and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0165] The activator may be an oxide of a group II metal. For example, the activator may be an oxide of beryllium, magnesium, calcium, strontium or barium. Suitably, the activator is an oxide of beryllium, magnesium or barium. In some embodiments, the activator is not an oxide of calcium or strontium.

[0166] In some embodiments, the activator is not an oxide of a group II metal.

[0167] Suitably, the activator is an oxide of a group II metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I). More suitably, the activator is an oxide of a group II metal and the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia), (Ib), (Ic) or (Id). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0168] Suitably, the activator is an oxide of a group II metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIa) or Formula (IIb). More suitably, the activator is an oxide of a group II metal and the per- or polyfluoroalkyl compound is a polymer comprising a monomeric repeating unit having the structure of Formula (IIb). In these embodiments, the step of pulverising may be conducted in a ball mill and / or is carried out for 0.5 ^ 12 hours.

[0169] In some embodiments, the activator is not: an oxalate of calcium;an oxide of calcium or strontium; a monosulfate of calcium; a persulfate or pyrosulfate of potassium; or a diphosphate of magnesium.

[0170] In some embodiments, the activator is not: an oxalate of calcium; an oxide of calcium or strontium; a sulfate of calcium; a sulfate of potassium; or a phosphate of magnesium.

[0171] In some embodiments, the activator is not: an oxalate of a group II metal; an oxide of a group II metal; a sulfate of a group I or group II metal; or a phosphate of a group II metal.

[0172] In some embodiments, the activator is not CaC2O4, CaO, SrO, SrO2, K2S2O7, K2S2O8, Mg3(PO4)2, or CaSO4.

[0173] Suitably, the activator is: (i) a phosphate, monosulfate, carbonate, oxalate, silicate or oxide of a group I metal; or (ii) a carbonate or silicate of a group II metal.

[0174] Suitably, the activator is: (i) a phosphate, carbonate, silicate or oxide of a group I metal; or (ii) a carbonate or silicate of a group II metal.

[0175] The activator may be selected from: (i) M2HPO4, MH2PO4, M3PO4, MPO3, M2PO3F, M4P2O7, M5P3O10, M2SO4, M2CO3, M2C2O4, MHCO3, M2SiO3 and M2O, wherein M is a group I metal; or (ii) M^HPO4, M^(H2PO4)2, M^CO3 and M^2SiO4, wherein M^ is a group II metal.

[0176] In the embodiments described herein, the group I metal (i.e., M) may be Li, Na or K. Suitably, the group I metal (i.e., M) is Na or K. Furthermore, the group II metal (i.e., M^) is suitably Ca. In these embodiments, the per- or polyfluoroalkyl compound may comprise a moiety having the structure of Formula (I).

[0177] Suitably, the activator is selected from:(i) M2HPO4, M3PO4, M4P2O7, M2SO4, M2CO3, M2C2O4, M2SiO3and M2O, wherein M is a group I metal; or (ii) M^CO3 and M^2SiO4, wherein M^ is a group II metal.

[0178] Suitably, the group I metal (i.e., M) is Li, Na or K and the group II metal (i.e., M^) is suitably Ca. In these embodiments, the per- or polyfluoroalkyl compound may comprise a moiety having the structure of Formula (I).

[0179] More suitably, the activator is selected from: (i) M2HPO4, M3PO4, M4P2O7, M2CO3, M2SiO3 and M2O, wherein M is a group I metal; or (ii) M^2SiO4, wherein M^ is a group II metal.

[0180] Suitably, the group I metal (i.e., M) is Li, Na or K and the group II metal (i.e., M^) is suitably Ca. In these embodiments, the per- or polyfluoroalkyl compound may comprise a moiety having the structure of Formula (I).

[0181] Even more suitably, the activator is selected from M3PO4 and M4P2O7, wherein M is agroup I metal. Suitably, the group I metal (i.e., M) is Li, Na or K. More suitably, Suitably, the group I metal (i.e., M) Na or K. Even more suitably, the Suitably, the group I metal (i.e., M) is K.

[0182] In some embodiments, the activator is K2HPO4, KH2PO4, K3PO4, Na3PO4, Li3PO4, KPO3, K4P2O7, Na4P2O7 K5P3O10, NaPO3, CaHPO4, Ca(H2PO4)2, K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4, Na2CO3, K2PO3F, KHCO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O. Suitably, the activator is K2HPO4, K3PO4, Na3PO4, K4P2O7, Na4P2O7,K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4, Na2CO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O. More suitably, the activator is K3PO4, Na3PO4, K4P2O7, K2CO3, K2SiO3, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O. Even more suitably, the activator is K3PO4or K4P2O7.

[0183] In some embodiments, the activator is K2HPO4. In some embodiments, the activator is KH2PO4. In some embodiments, the activator is K3PO4. In some embodiments, the activator is Na3PO4. In some embodiments, the activator is Li3PO4. In some embodiments, the activator is KPO3. In some embodiments, the activator is K4P2O7. In some embodiments, the activator isNa4P2O7. In some embodiments, the activator is K5P3O10. In some embodiments, the activator isNaPO3. In some embodiments, the activator is CaHPO4. In some embodiments, the activator is Ca(H2PO4)2. In some embodiments, the activator is K2SO4. In some embodiments, the activator is Na2SO4. In some embodiments, the activator is K2CO3. In some embodiments, the activator is CaCO3. In some embodiments, the activator is K2C2O4. In some embodiments, the activator is Na2CO3. In some embodiments, the activator is K2PO3F. In some embodiments, the activator is KHCO3. In some embodiments, the activator is K2SiO3. In some embodiments, the activator isNa2C2O4. In some embodiments, the activator is Na2SiO3. In some embodiments, the activator is Li2SiO3. In some embodiments, the activator is Ca2SiO4. In some embodiments, the activator is Na2O. In some embodiments, the activator is Li2O. In some embodiments, the activator is SiO2.

[0184] Suitably, the activator is K2HPO4, KH2PO4, K3PO4, Na3PO4, Li3PO4, KPO3, K4P2O7, Na4P2O7K5P3O10, NaPO3, CaHPO4, Ca(H2PO4)2, K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4,Na2CO3, K2PO3F, KHCO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O and theper- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ECTFE, ETFE, PVDF-HFP, PVF, FEP, PP-PTFE, PFOA, PFNA, PFDA, PFUnDA, PFDoDA, PFOS, PFOSA, KPFHxS, KPFBS, FTOH, PFPD, PFBA, PFPeA, PFHxA, PFHpA, PFTrDA, PFTeDA, PFPeDA, PFHxDA, PFBS, PFPeS, PFHxS, PFDS, PFBPA, PFHxPA, PFOPA, PFDPA, PFPiA, FBSA, Me-FBSA, Et-FBSA, FOSA, Me-FOSA, Et-FOSA, FBSE, Me-FBSE, Et-FOSE, Me-FOSE, Et-FOSE, a diPAPs a FTPA, a FTSA, a PFA or FC-70.

[0185] Suitably, the activator is K2HPO4, KH2PO4, K3PO4, Na3PO4, Li3PO4, KPO3, K4P2O7, Na4P2O7 K5P3O10, NaPO3, CaHPO4, Ca(H2PO4)2, K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4, Na2CO3, K2PO3F, KHCO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O and the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP, PP- PTFE, PFOA, PFNA, PFDA, PFUnDA, PFDoDA, PFOS, PFOSA, KPFHxS, KPFBS, FTOH, PFPD or FC-70.

[0186] Suitably, the activator is K2HPO4, K3PO4, Na3PO4, K4P2O7, Na4P2O7, K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4, Na2CO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O and the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP or PP-PTFE.

[0187] Suitably, the activator is K3PO4, Na3PO4, K4P2O7, K2CO3, K2SiO3, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O and the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE or PVDF-HFP.

[0188] Suitably, the activator is K3PO4or K4P2O7and the per- or polyfluoroalkyl compound is PTFE.

[0189] For each C-F bond present within the per- or polyfluoroalkyl compound, >0.125 equivalents of the activator may be pulverised with 1 equivalent of the per- or polyfluoroalkyl compound. Where the per- or polyfluoroalkyl compound is polymeric, reference is made to the number of C-F bonds in 1 monomeric unit, as described using the following schematic:

[0190] In this example, 5 equivalents of the activator are pulverised with 1 equivalent of PTFE as the per- or polyfluoroalkyl compound. There are 4 C-F bonds in 1 monomeric unit of PTFE, meaning that for each C-F bond present in the per- or polyfluoroalkyl compound there are 5 / 4 = 1.25 equivalents of the activator.

[0191] By way of another example, when PVDF is the per- or polyfluoroalkyl compound, 1 equivalent (molar mass: 64.03 g / mol per monomeric unit, sample mass: 54 mg, 0.841 mmol) may be pulverised with 2.5 equivalents of the activator (K3PO4, molar mass: 212.27 g / mol, sample mass: 446 mg, 2.10 mmol). There are 2 C-F bonds in 1 monomeric unit of PVDF, meaning that for each C-F bond present in the per- or polyfluoroalkyl compound, there are 2.5 / 2 = 1.25 equivalents of the activator.

[0192] By way of yet another example, when PFOA is the per- or polyfluoroalkyl compound, 1 equivalent (molar mass: 414.07 g / mol, sample mass: 47 mg, 0.114 mmol) may be pulverised with 18.75 equivalents of the activator (K3PO4, molar mass: 212.27 g / mol, sample mass: 453 mg, 2.13 mmol). There are 15 C-F bonds in PFOA, meaning that for each C-F bond present in the per- or polyfluoroalkyl compound, there are 18.75 / 15 = 1.25 equivalents of the activator.

[0193] Suitably, for each C-F bond present in the per of polyfluoroalkyl compound, >0.25 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. More suitably, for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-10 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. More suitably, for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. More suitably, for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-2.5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. Even more suitably, for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-2 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. Even more suitably, for each C-F bond present in the per of polyfluoroalkyl compound, 0.5-2 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. Yet still even more suitably, for each C-F bond present in the per of polyfluoroalkyl compound, 0.5-1.5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound.Yet still even more suitably, for each C-F bond present in the per of polyfluoroalkyl compound, 0.625-1.5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. Yet still even more suitably, for each C-F bond present in the per of polyfluoroalkyl compound, 1-1.4 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. Most suitably, for each C-F bond present in the per of polyfluoroalkyl compound, 1.2-1.3 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound.

[0194] As outlined hereinbefore, the process of the present invention may degrade a variety of PFAS into fluorine sources in a regenerative / recyclable manner. In particular, the inventors have found that the activator may be recycled once it has been pulverised with a per- or polyfluoroalkyl compound. An example of this concept is provided in Fig.12, wherein an activator salt residue is formed (e.g., KxH3-xPO4) once the activator and the per- or polyfluoroalkyl compound have been pulverised together. The activator salt residue can be subsequently extracted (e.g., by precipitation) and worked up (e.g., with KOH) to afford a mixture of recovered activator salts (e.g., K3PO4CYC). The mixture of recovered activator salts may then be reused as an activator in the process of the present invention. Accordingly, the process may further comprise the step of forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together. Suitably, the mixture of recovered activator salts is used in a subsequent step of pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts. Thus, the process of the present invention may comprise the following steps: I. pulverising together a per- or polyfluoroalkyl compound and an activator, wherein the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal (e.g., a phosphate of a group I or group II metal); II. forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together; and III. pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts.

[0195] The step of forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together may comprise extracting an insoluble activator salt residue (e.g., by precipitation) from the reaction mixture (e.g., of the per- or polyfluoroalkyl compound and the activator). Suitably, the insoluble activator salt residue is treated with H2O and KOH to form a mixture of recovered activator salts.

[0196] The activator may be a phosphate of a group I or group II metal and the mixture of recovered activator salts may comprise phosphates of the group I or group II metal. Suitably, theactivator is a phosphate of a group I metal and the mixture of recovered activator salts comprises phosphates of the group I metal. More suitably, the activator is K3PO4 and the mixture of recovered activator salts comprises K3PO4and / or K4P2O7. Even more suitably, the activator is K3PO4 and the mixture of recovered activator salts comprises K3PO4 and K4P2O7. The mixture of recovered activator salts may further comprise K2CO3 and / or K2C2O4.

[0197] Suitably, the step of pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts is conducted using any of the conditions / processes / techniques described herein for any pulverising step.

[0198] Suitably, the per- or polyfluoroalkyl compound and the activator described in the steps above are as described anywhere herein. For example, it may be that the per- or polyfluoroalkyl compound is PTFE and the activator is K3PO4.

[0199] The step of pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts may result in a mixture comprising at least one fluorinated species. The at least one fluorinated species may be as described anywhere herein.

[0200] As described hereinbefore, the step of pulverising together the per- or polyfluoroalkyl compound and the activator may result in a mixture comprising at least one fluorinated species. The at least one fluorinated species is a fluorine-containing compound that is not the per- or polyfluoroalkyl compound. Suitably, the at least one fluorinated species comprises KF, K2PO3F, K3HPO4F, or a mixture thereof (e.g., PTFE mix). More suitably, the at least one fluorinated species comprises KF, K2PO3F, or a mixture thereof. It will be understood that the precise nature of the at least one fluorinated species will depend on the particular activator used.

[0201] The aforementioned fluorinated species may have a variety of industrial uses. For example, KF can be used to form 4-fluorobenzaldehyde, the building block used in the synthesis of Lipitor. Tetraalkylammonium fluoride reagents prepared from K2PO3F were successfully employed in the syntheses of 4-fluoronitrobenzene, 2-chloro-1-fluoro-4-nitrobenzene, 2,6- difluorobenzonitrile, and methyl 2-fluoropropanoate. These fluorochemicals are essential building blocks in the synthesis of various organo-fluorine containing compounds, including the pharmaceuticals Cabozantinib (anti-cancer medication), (+)-SJ733 (anti-malaria agent), Lipitor (cholesterol-lowering), Dacomitinib (lung carcinoma), Rufinamide (seizure disorders), as well as the agrochemicals Indaziflam (preemergent herbicide) and Triaziflam (herbicide).

[0202] Therefore, the process may further comprise of using the mixture, or the at least one fluorinated species contained therein, as a fluorinating agent.

[0203] The present invention provides a mixture comprising one or more fluorinated species obtainable by the processes described herein. The mixture may be used as a fluorinating agent.

[0204] The following numbered statements 1 to 153 are not claims, but instead describe particular aspects and embodiments of the invention: 1. A process comprising the step of pulverising together a per- or polyfluoroalkyl compound and an activator, wherein the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal. 2. The process of statement 1, wherein the step of pulverising is conducted in a ball mill, a resonant acoustic mixer, a pestle and mortar or a twin screw extruder. 3. The process of statement 2, wherein the ball mill is a planetary ball mill, a vibratory ball mill, an attritor ball mill or a tumbling ball mill. 4. The process of any one of the preceding statements, wherein the step of pulverising is carried out for 0.5 ^ 12 hours. 5. The process of any one of the preceding statements, wherein the step of pulverising is carried out for 0.5 ^ 6 hours. 6. The process of any one of the preceding statements, wherein the step of pulverising is carried out for 1 ^ 5 hours. 7. The process of any one of the preceding statements, wherein the step of pulverising comprises ball milling the reactants together at a frequency of 0.5 ^ 80 Hz. 8. The process of any one of the preceding statements, wherein the step of pulverising comprises ball milling the reactants together at a frequency of 5 ^ 65 Hz. 9. The process of any one of the preceding statements, wherein the step of pulverising comprises ball milling the reactants together at a frequency of 15 ^ 45 Hz. 10. The process of any one of the preceding statements, wherein the step of pulverising comprises ball milling the reactants together at a frequency of 20 ^ 40 Hz.11. The process of any one of the preceding statements, wherein the step of pulverising is conducted in the absence of any solvent. 12. The process of any one of the preceding statements, wherein >50wt% of the per- or polyfluoroalkyl compound, the activator and any reaction products derived therefrom, remain in the solid state throughout the process. 13. The process of any one of the preceding statements, wherein >70wt% of the per- or polyfluoroalkyl compound, the activator and any reaction products derived therefrom, remain in the solid state throughout the process. 14. The process of any one of the preceding statements, wherein >90wt% of the per- or polyfluoroalkyl compound, the activator and any reaction products derived therefrom, remain in the solid state throughout the process. 15. The process of any one of the preceding statements, wherein >95wt% of the per- or polyfluoroalkyl compound, the activator and any reaction products derived therefrom, remain in the solid state throughout the process. 16. The process of any one of the preceding statements, wherein the pulverising step results in the degradation of C-F bonds. 17. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I):wherein R1is H, halo, (1-3C)haloalkyl or (1-3C)haloalkoxy. 18. The process of statement 17, wherein R1 is H, F, Cl, Br, (1-2C)haloalkyl or (1- 2C)haloalkoxy.19. The process of statement 17 or 18, wherein R1is H, F, Cl, CH2F, CF2H, CF3or OCF3. 20. The process of statement 17, 18 or 19, wherein R1is H, F, Cl or CF3. 21. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ia):wherein R, R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl or (1- 3C)haloalkoxy, with the proviso that at least one of R, R1, R2and R3is F. 22. The process of statement 21, wherein R, R1, R2 and R3 are each independently selected from H, F, Cl, Br, (1-2C)haloalkyl and (1-2C)haloalkoxy. 23. The process of statement 21 or 22, wherein R, R1, R2and R3are each independently selected from H, F, Cl, CH2F, CF2H, CF3 and OCF3. 24. The process of statement 21, 22 or 23, wherein R, R1, R2and R3are each independently selected from H, F, Cl and CF3. 25. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ib):wherein R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy.26. The process of statement 25, wherein R1, R2and R3are each independently selected from H, F, Cl, Br, (1-2C)haloalkyl and (1-2C)haloalkoxy. 27. The process of statement 25 or 26, wherein R1, R2and R3are each independently selected from H, F, Cl, CH2F, CF2H, CF3 and OCF3. 28. The process of statement 25, 26 or 27, wherein R1, R2and R3are each independently selected from H, F, Cl and CF3. 29. The process of any one of statements 25-28, wherein: (i) R1is H, F or CF3; and (ii) R2 and R3 are each independently selected from H, F and Cl. 30. The process of any one of statements 25-29, wherein: (i) R1, R2 and R3 are F; (ii) R1is F, and R2and R3are H; (iii) R1is F, R2is F and R3is Cl; (iv) R1is CF3, and R2and R3are F; or (v) R1, R2and R3are H. 31. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound comprises a moiety having any one of the following structures:32. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound comprises a moiety having the following structure:. 33. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ic):wherein X is a terminal end group and R, R1, R2 and R3 are each independently selected from H, halo, (1-3C)haloalkyl or (1-3C)haloalkoxy, with the proviso that at least one of R, R1, R2and R3is F. 34. The process of statement 33, wherein R, R1, R2and R3are each independently selected from H, F, Cl, Br, (1-2C)haloalkyl and (1-2C)haloalkoxy. 35. The process of statement 33 or 34, wherein R, R1, R2and R3are each independently selected from H, F, Cl, CH2F, CF2H, CF3 and OCF3. 36. The process of statement 33, 34 or 35, wherein R, R1, R2 and R3 are each independently selected from H, F, Cl and CF3. 37. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Id):wherein X is a terminal end group and R1, R2 and R3 are each independently selected from H, halo, (1-3C)haloalkyl and (1-3C)haloalkoxy.38. The process of statement 37, wherein R1, R2and R3are each independently selected from H, F, Cl, Br, (1-2C)haloalkyl and (1-2C)haloalkoxy. 39. The process of statement 37 or 38, wherein R1, R2and R3are each independently selected from H, F, Cl, CH2F, CF2H, CF3 and OCF3. 40. The process of statement 37, 38 or 39, wherien R1, R2and R3are each independently selected from H, F, Cl and CF3. 41. The process of any one of statements 37-40, wherein X is -Ra, -(CH2)Y-Ra, -ORa, - C(O)Ra, -COORa, -C(O)NRa, -SO3Ra, -SO3K, -SO2NRaRb, -PO3RaRb, -PO2Ra or -SO2Ra, where Y is an integer selected from 1 to 8, and Raand Rbare each independently selected from H, (1- 6C)alkyl or (1-6C)haloalkyl. 42. The process of statement 41, wherein Y is an integer selected from 1 to 6, and Raand Rb are each independently selected from H, (1-4C)alkyl or (1-4C)haloalkyl. 43. The process of statement 41 or 42, wherein Y is an integer selected from 1 to 4, and Raand Rbare each independently selected from H, (1-2C)alkyl or (1-2C)haloalky. 44. The process of statement 41, 42 or 43, wherein Y is an integer selected from 1 or 2, and Ra and Rb are each independently selected from H, CH3 or CF3. 45. The process of any one of statements 37-44, wherein X is a group selected from -H, - CH3, -CF3, -OH, -OCH3, -OCF3, -CH2OH, -CH2CH2OH, -COOH, -C(O)NH, -C(O)NMe, -SO3H, - SO3K, -SO3Me, -SO2NH2, -SO2NMe2, -PO3H2, -PO3Me2, -PO2H, -PO2Me, -SO2H, -SO2Me, - C(O)NH-(CH2)3-NMe3+or -CH2CH2-SO2NH-(CH2)3-NMe2+-CH2-COO-.46. The process of any one of statements 37-45, wherein X is a group selected from -H, - CH3, -CF3, -OH, -OCH3, -OCF3, -CH2CH2OH, -COOH, -C(O)NH, -SO3H, -SO3K, -SO2NH2, - PO3H2, -PO2H or -SO2H. 47. The process of any one of statements 37-46, wherein X is a group selected from -H, - CF3, -OH, -CH2CH2OH, -COOH, -SO3H, -SO3K, -PO3H2, -PO2H or -SO2H. 48. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound is a polymer. 49. The process of statement 48, wherein the polymer comprises a monomeric repeating unit having the structure of Formula (IIa):wherein R, R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy, with the proviso that at least one of R, R1, R2 and R3 is F. 50. The process of statement 49, wherein R, R1, R2and R3are each independently selected from H, F, Cl, Br, (1-2C)haloalkyl and (1-2C)haloalkoxy. 51. The process of statement 49 or 50, wherein R, R1, R2and R3are each independently selected from H, F, Cl, CH2F, CF2H, CF3 and OCF3. 52. The process of statement 49, 50 or 51, wherien R, R1, R2and R3are each independently selected from H, F, Cl and CF3. 53. The process of any one of statements 48-52, wherein the polymer comprises a monomeric repeating unit having the structure of Formula (IIb):wherein R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy. 54. The process of statement 53, wherein R1, R2and R3are each independently selected from H, F, Cl, Br, (1-2C)haloalkyl and (1-2C)haloalkoxy. 55. The process of statement 53 or 54, wherein R1, R2 and R3 are each independently selected from H, F, Cl, CH2F, CF2H, CF3 and OCF3. 56. The process of statement 53, 54 or 55, wherein R1, R2 and R3 are each independently selected from H, F, Cl and CF3. 57. The process of any one of statements 53-56, wherein: (i) R1 is H, F or CF3; and (ii) R2and R3are each independently selected from H, F and Cl. 58. The process of any one of statements 53-57, wherein: (i) R1, R2and R3are F; (ii) R1 is F, and R2 and R3 are H; (iii) R1 is F, R2 is F and R3 is Cl; (iv) R1is CF3, and R2and R3are F; or (v) R1, R2and R3are H. 59. The process of any one of statements 48-58, wherein the polymer comprises a monomeric repeating unit selected from:60. The process of any one of statements 48-59, wherein the polymer comprises the following monomeric repeating unit:. 61. The process of any one of statements 48-60, wherein the polymer comprises at least 10 monomeric repeating units. 62. The process of any one of statements 48-61, wherein the polymer comprises at least 20 monomeric repeating units. 63. The process of any one of statements 48-62, wherein the polymer comprises at least 50 monomeric repeating units. 64. The process of any one of statements 48-63, wherein the polymer comprises at least 100 monomeric repeating units. 65. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound is a perfluoroalkyl carboxylic acid, a perfluoroalkyl sulfonic acid, a perfluoroalkyl phosphonic acid, a perfluoroalkyl phosphinic acid, a perfluoroalkane sulfonyl fluoride, a fluorotelomer, a fluoropolymer or a perfluoropolyther. 66. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ECTFE, ETFE, PVDF-HFP, PVF, FEP, PP-PTFE, PFOA, PFNA, PFDA, PFUnDA, PFDoDA, PFOS, PFOSA, KPFHxS, KPFBS, FTOH, PFPD, PFBA, PFPeA, PFHxA, PFHpA, PFTrDA, PFTeDA, PFPeDA, PFHxDA, PFBS, PFPeS, PFHxS, PFDS, PFBPA, PFHxPA, PFOPA, PFDPA, PFPiA, FBSA, Me-FBSA, Et-FBSA, FOSA, Me-FOSA, Et-FOSA, FBSE, Me-FBSE, Et-FOSE, Me-FOSE, Et-FOSE, diPAPs, a FTPA, a FTSA, a PFA or FC-70. 67. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP, PP-PTFE, PFOA, PFNA, PFDA, PFUnDA, PFDoDA, PFOS, PFOSA, KPFHxS, KPFBS, FTOH, PFPD or FC-70. 68. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP or PP-PTFE. 69. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE or PVDF-HFP. 70. The process of any one of the preceding statements, wherein the per- or polyfluoroalkyl compound is PTFE. 71. The process of any one of the preceding statements, wherein the activator is a phosphate of a group I metal. 72. The process of any one of the preceding statements, wherein the activator is a phosphate of lithium, sodium or potassium. 73. The process of any one of the preceding statements, wherein the activator is a phosphate of sodium or potassium. 74. The process of any one of the preceding statements, wherein the activator is a phosphate of potassium. 75. The process of any one of the preceding statements, wherein the activator is a phosphate of a group II metal.76. The process of any one of the preceding statements, wherein the activator is a phosphate of calcium. 77. The process of any one of the preceding statements, wherein the activator is a sulfate of a group I metal. 78. The process of any one of the preceding statements, wherein the activator is a sulfate of lithium, sodium or potassium. 79. The process of any one of the preceding statements, wherein the activator is a sulfate of sodium or potassium. 80. The process of any one of the preceding statements, wherein the activator is a monosulfate of sodium or potassium. 81. The process of any one of the preceding statements, wherein the activator is a monosulfate of sodium. 82. The process of any one of the preceding statements, wherein the activator is a sulfate of a group II metal. 83. The process of any one of the preceding statements, wherein the activator is a sulfate of magnesium. 84. The process of any one of the preceding statements, wherein the activator is a carbonate of a group I metal. 85. The process of any one of the preceding statements, wherein the activator is a carbonate of lithium, sodium or potassium. 86. The process of any one of the preceding statements, wherein the activator is a carbonate of sodium or potassium. 87. The process of any one of the preceding statements, wherein the activator is a carbonate of a group II metal.88. The process of any one of the preceding statements, wherein the activator is a carbonate of calcium or magnesium. 89. The process of any one of the preceding statements, wherein the activator is an oxalate of a group I metal. 90. The process of any one of the preceding statements, wherein the activator is an oxalate of lithium, sodium or potassium. 91. The process of any one of the preceding statements, wherein the activator is an oxalate of sodium or potassium. 92. The process of any one of the preceding statements, wherein the activator is an oxalate of a group II metal. 93. The process of any one of the preceding statements, wherein the activator is an oxalate of magnesium. 94. The process of any one of the preceding statements, wherein the activator is a silicate of a group I metal. 95. The process of any one of the preceding statements, wherein the activator is a silicate of lithium, sodium or potassium. 99. The process of any one of the preceding statements, wherein the activator is a silicate of sodium or potassium. 100. The process of any one of the preceding statements, wherein the activator is a silicate of a group II metal. 101. The process of any one of the preceding statements, wherein the activator is a silicate of calcium or magnesium. 102. The process of any one of the preceding statements, wherein the activator is a silicate of calcium.103. The process of any one of the preceding statements, wherein the activator is an oxide of a group I metal. 104. The process of any one of the preceding statements, wherein the activator is an oxide of lithium, sodium or potassium. 105. The process of any one of the preceding statements, wherein the activator is an oxide of lithium or sodium. 106. The process of any one of the preceding statements, wherein the activator is an oxide of a group II metal. 107. The process of any one of the preceding statements, wherein the activator is an oxide of beryllium, magnesium or barium. 108. The process of any one of the preceding statements, wherein the activator is not: an oxalate of a group II metal; an oxide of a group II metal; a sulfate of a group I or group II metal; or a phosphate of a group II metal. 109. The process of any one of the preceding statements, wherein the activator is not CaC2O4, CaO, SrO, SrO2, K2S2O7, K2S2O8, Mg3(PO4)2, or CaSO4. 110. The process of any one of the preceding statements, wherein the activator is: (i) a phosphate, monosulfate, carbonate, oxalate, silicate or oxide of a group I metal; or (ii) a carbonate or silicate of a group II metal. 111. The process of any one of the preceding statements, wherein the activator is: (i) a phosphate, carbonate, silicate or oxide of a group I metal; or (ii) a carbonate or silicate of a group II metal. 112. The process of any one of the preceding statements, wherein the activator is selected from:(i) M2HPO4, MH2PO4, M3PO4, MPO3, M2PO3F, M4P2O7, M5P3O10, M2SO4, M2CO3, M2C2O4, MHCO3, M2SiO3 and M2O, wherein M is a group I metal; or (ii) M^HPO4, M^(H2PO4)2, M^CO3 and M^2SiO4, wherein M^ is a group II metal. 113. The process of any one of the preceding statements, wherein the activator is selected from: (i) M2HPO4, M3PO4, M4P2O7, M2SO4, M2CO3, M2C2O4, M2SiO3 and M2O, wherein M is a group I metal; or (ii) M^CO3and M^2SiO4, wherein M^ is a group II metal. 114. The process of any one of the preceding statements, wherein the activator is selected from: (i) M2HPO4, M3PO4, M4P2O7, M2CO3, M2SiO3 and M2O, wherein M is a group I metal; or (ii) M^2SiO4, wherein M^ is a group II metal. 115. The process of any one of the preceding statements, wherein the activator is selectedfrom M3PO4 and M4P2O7, wherein M is a group I metal.116. The process of any one of statements 112-115, wherein the group I metal (i.e., M) is Li, Na or K. 117. The process of any one of statements 112-116, wherein the group I metal (i.e., M) Na or K. 118. The process of any one of statements 112-117, wherein the group I metal (i.e., M) is K. 119. The process of any one of statements 112-118, wherein the group II metal (i.e., M^) is Ca. 120. The process of any one of the preceding statements, wherein the activator is K2HPO4, KH2PO4, K3PO4, Na3PO4, Li3PO4, KPO3, K4P2O7, Na4P2O7 K5P3O10, NaPO3, CaHPO4,Ca(H2PO4)2, K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4, Na2CO3, K2PO3F, KHCO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O. 121. The process of any one of the preceding statements, wherein the activator is K2HPO4, K3PO4, Na3PO4, K4P2O7, Na4P2O7, K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4, Na2CO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O. 122. The process of any one of the preceding statements, wherein the activator is K3PO4, Na3PO4, K4P2O7, K2CO3, K2SiO3, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O. 123. The process of any one of the preceding statements, wherein the activator is K3PO4 or K4P2O7. 124. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, >0.125 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 125. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, >0.25 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 126. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-10 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 127. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 128. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-2.5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 129. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-2 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound.130. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 0.5-2 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 131. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 0.5-1.5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 132. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 0.625-1.5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 133. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 1-1.4 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 134. The process of any one of the preceding statements, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 1.2-1.3 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound. 135. The process of any one of the preceding statements, wherein the process is regenerative / recyclable. 136. The process of any one of the preceding statements, wherein the activator is recycled once it has been pulverised with a per- or polyfluoroalkyl compound. 137. The process of any one of the preceding statements, wherein the process further comprises the step of forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together. 138. The process of statement 137, wherein the mixture of recovered activator salts is used in a step of pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts.139. The process of any one of the preceding statements, wherein the process comprises the following steps: I. pulverising together a per- or polyfluoroalkyl compound and an activator, wherein the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal (e.g., a phosphate of a group I or group II metal); II. forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together; and III. pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts. 140. The process of statement 137, 138 or 139, wherein the step of forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together comprises extracting an insoluble activator salt residue from the reaction mixture. 141. The process of statement 140, wherein the insoluble activator salt residue is treated with H2O and KOH to form a mixture of recovered activator salts. 142. The process of any one of statements 137-141, wherein the activator is a phosphate of a group I or group II metal and the mixture of recovered activator salts comprises phosphates of the group I or group II metal. 143. The process of any one of statements 137-142, wherein the activator is a phosphate of a group I metal and the mixture of recovered activator salts comprises phosphates of the group I metal. 144. The process of any one of statements 137-143, wherein the activator is K3PO4 and the mixture of recovered activator salts comprises K3PO4and / or K4P2O7. 145. The process of any one of statements 137-144, wherein the activator is K3PO4and the mixture of recovered activator salts comprises K3PO4 and K4P2O7.146. The process of statement 145, wherein the mixture of recovered activator salts further comprise K2CO3 and / or K2C2O4. 147. The process of any one of statements 137-146, wherein the step of pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts results in a mixture comprising at least one fluorinated species. 148. The process of any one of the preceding statements, wherein the step of pulverising together the per- or polyfluoroalkyl compound and the activator results in a mixture comprising at least one fluorinated species. 149. The process of statement 147 or 148, wherein the at least one fluorinated species comprises KF, K2PO3F, K3HPO4F, or a mixture thereof (e.g., PTFE mix). 150. The process of statement 147, 148 or 149, wherein the at least one fluorinated species comprises KF, K2PO3F, or a mixture thereof. 151. The process of any one of statements 147-150, wherein the process further comprises using the mixture, or the at least one fluorinated species contained therein, as a fluorinating agent. 152. A mixture comprising one or more fluorinated species obtainable by the process of any one of statements 147-151. 153. Use of the mixture of statement 152 as a fluorinating agent.BRIEF DESCRIPTION OF THE DRAWINGS

[0205] The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings (also ^Figure^ and ^FIG.^ herein), of which include: Fig. 1. Phosphate-enabled mechanochemical PFAS upcycling process. (A) Reaction optimization by screening various phosphate activators for PFAS degradation. The yield of KF and K2PO3F was determined by quantitative19F NMR spectroscopy. Identical results were obtained using a zirconium jar with zirconium balls. (B) Identification of F-, C- and P- content of PTFE-mix by quantitative19F NMR,31P NMR,13C NMR, Raman spectroscopy of isolated insoluble carbon, PXRD patterns and solid-state NMR spectroscopy. (C) Control experiments (ball milling with 15mL jar, 2 x 7 g balls, 35 Hz, 3 h, total mass 0.5 g). (D) Density functional theory (DFT) study on the nucleophilic attack of C-F bonds. Fig.2. Table of results for activator screening. Fig.3. Stoichiometric activator screening for K3PO4. Fig.4. Stoichiometric activator screening for K4P2O7. Fig.5. Stoichiometric activator screening for a variety of group I and group II carbonates. Fig.6. Stoichiometric activator screening for a variety of group I oxalates. Fig.7. Stoichiometric activator screening for a variety of group I and group II silicates. Fig.8. Stoichiometric activator screening for a variety of group I oxides. Fig.9. Stoichiometric activator screening for a variety of group I sulfates. Fig.10. Synthesis of fluorochemicals from PFAS. (A) Scope of PFAS destruction. The total yield of released fluoride (both F- and PO3F2-) as well as their ratio was determined by quantitative19F NMR spectroscopy (in 10% D2O in H2O using NaOTf as an internal standard). Reactions were performed in triplicates and average yields are reported.aReaction was performed once.bThe yield was calculated based on the fluorine content of the co-polymer as determined by elemental analysis.cThe amount of K3PO4 was increased to 2 equiv. / F.dReaction was carried out for 6 h. (B) Synthesis of KF and tetraalkylammonium fluorides from PTFE under mechanochemical conditions. Yields of isolated products are reported. Also shown is upcycling of PFAS from consumer items and adsorbed pollutants (C) Building block synthesis of high-value fluorochemicals using PFAS-derived fluorinating reagents (0.5 mmol scale unless otherwise stated). Yields of isolated products are reported.eYield was determined by quantitative19F NMR (in CDCl3 using 4-fluoroanisole as an internal standard).fKF was isolated from a mixture of decomposed PFAS, including PFOS, PFOA, PFNA, PFDA, PFOSA, and 8:2 FTOH. Fig.11. Yield of isolated KF and mixture of recovered activator salts for three cycles.Fig. 12. Reaction scheme showing the steps of pulverising together a per- or polyfluoroalkyl compound and an activator, forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together, and pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts. FIG.13. illustrates an example scheme and experimental results for degradation of PTFE using an a variety of silicate activators according to this disclosure. FIG.14. illustrates example results for conversion of a variety of PFAS compounds to inorganic fluorine salts using three different silicate activators according to embodiments described herein. FIG. 15. illustrates an example scheme for degradation of PFAS compounds according to embodiments disclosure herein. FIG. 16. illustrates an example scheme using K2SiO3as an activator for degradation of PFAS compounds to form KF according to embodiments disclosure herein. FIG.17. illustrates an example scheme using Na2SiO3 as an activator for degradation of PFAS compounds to form NaF according to embodiments disclosure herein. EXAMPLES One or more examples of the invention will now be described, for the purpose of illustration only, with reference to the accompanying figures: Materials and Methods

[0206] Unless otherwise stated, all reagents were purchased from commercial suppliers (Sigma-Aldrich, Alfa Aesar, Fluorochem, Apollo Scientific and Fisher Chemicals), used without further purification and stored under ambient conditions. Solvents were purchased from commercial suppliers and used as provided without further purification.

[0207] Reagents: poly(tetrafluoroethylene) (Fluorochem, CAS 9002-84-0), potassium pyrophosphate (K4P2O7, Fluorochem, 99.0%, CAS 7320-34-5), potassium phosphate (K3PO4, 98%, Sigma Aldrich, CAS 7778-53-2), dipotassium hydrogen phosphate (K2HPO4, 98.0%, Alfa Aesar, CAS 7758-11-4), potassium dihydrogen phosphate (KH2PO4, 99.0%, Alfa Aesar, CAS 7778-77-0) and sodium pyrophosphate (Na4P2O7, 95.0%, Sigma Aldrich, CAS 7722-88- 5) were dried before use under high vacuum at 100 overnight and stored in a desiccator. Fluorspar (acid grade) was purchased from Mistral Industrial Chemicals (UK), sourced from Minersa group (Asturias region, Spain) and contains CaF2(> 97%), total carbonates (< 1.50%), SiO2 (<1.00%), BaO4 (<0.50 %), Pb (< 0.10%), Fe2O3 (< 0.10%), S (< 0.15%), H2O (< 1.0%). Fluorspar (acid grade) was used without drying and stored under ambient conditions.

[0208] Deuterated solvents were purchased from VWR Chemicals or Sigma Aldrich and used as received.

[0209] Ball milling was carried out using either a Retsch MM 400 mixer mill (30 Hz experiments), Retsch MM 500 Vario mixer mill (35 Hz experiments) or an Insolido IST636 mixer mill (35 Hz experiments). Unless otherwise stated, mechanochemical reactions were carried out in 15 mL or 30 mL FormTech Scientific (FTS) stainless steel (316) jars with stainless steel (316) balls (4 g (10 mm), 7 g (12 mm), 16 g (15 mm)), 15 mL or 30 mL FormTech Scientific (FTS) zirconium jar with zirconium balls (12 mm, 15 mm). No precaution was taken to exclude air and moisture.

[0210] Thin layer chromatography (TLC) was carried out on silica gel pre-coated aluminium sheets (Merck Kieselgel 60 F254 plates) and visualized using ultraviolet light of wavelength 254 nm or potassium permanganate stain. Flash column chromatography (FFC) was performed on Merck silica gel (60, particle size 0.040-0.063 mm). Solution based reactions were stirred at 1000 rpm using an IKA heating plate, aluminium block and borosilicate glass vials or microwave glass vials.

[0211] 1H NMR,13C NMR,31P NMR and19F NMR spectra were recorded on Bruker AVIIIHD 400, AVIIIHD 500, AVII 500 or AV NEO 600.1H NMR spectra were recorded at 400 or 500 MHz.13C NMR spectra were recorded at 101 or 126 MHz with1H decoupling,31P NMR spectra were recorded at 203 MHz and19F NMR spectra were recorded at 377 or 471 MHz.1H NMR,13C NMR,31P NMR and 19F NMR spectral data are reported as chemical shifts ( ) in parts per million (ppm)relative to the solvent peak using the Bruker internal referencing procedure (edlock). Coupling constants, J, are reported in Hz to the nearest 0.1 Hz. Unless otherwise stated,13C spectra are1H decoupled and reported coupling constants for13C spectra correspond to19F^13C heteronuclear coupling. Data are reported as follows: chemical shift, multiplicity (s = singlet, d = doublet, t = triplet, q = quartet, pent = pentet, hept = heptet, br = broad, m = multiplet), coupling constants (Hz) and integration. NMR spectra were processed with MestReNova 14.1.2 or Topspin 3.5 or 4.0. Quantitative NMR analysis was determined using 4-fluoroanisole or 1,3,5- trimethoxybenzene as an internal standard. The standard was added to the crude reaction mixture after solvent evaporation, dilution in CDCl3, and an aliquot was taken to be analysed by19F NMR and1H NMR.

[0212] High resolution mass spectra were determined on a Thermo Exactive High-Resolution Orbitrap FTMS mass spectrometer (ESI+ or ESI-), Agilent 5977B GC-MS (EI+). Some compounds were found to be unstable under a variety of MS ionization methods (CI, EI, ESI, GC-MS) and therefore no HRMS could be obtained for them. APCI was used as an alternative ionization method.

[0213] Reaction progress and initial structural characterization (solid-state reactions) was performed using X ray powder diffraction (PXRD) data collected using a Bruker D8 Advance X-ray diffractometer (Bragg Brentano geometry); the radiations Cu K 1,2 were used. Profile-matching refinements were performed on the XRD patterns for cell parameters determination, using the Rietveld refinement method with the TOPAS V.7 software.

[0214] Infrared spectra were recorded as the neat compound (neat) or as an evaporated solution (thin layer film) using a Bruker Tensor 27 FTIR spectrometer. Absorptions are reported in wavenumber (cm-1). Processes for preparing fluorinated species

[0215] The present inventors have devised an operationally simple solution to the PFAS challenges described hereinbefore. The process of the present invention is suitable for use with a wide range of PFAS and activators, such as potassium phosphate salts, and result in the recovery of fluorine content from PFAS (e.g., as KF or K2PO3F) upon mechanical stimulation. The fluorine content recovered from PFAS can serve as a precursor for various tetraalkylammonium salts commonly used in industrial fluorination processes.

[0216] During the course of an investigation into the synthesis of fluorochemicals from acid grade fluorspar (29), the inventors observed that ball milling of fluorspar and a phosphate salt activator in a stainless-steel jar with sealing rings made of polytetrafluoroethylene (PTFE, Teflon) instead of rubber, gave noticeably higher yields of Fluoromix, a fluorinating reagent composed of the two crystalline phases K3HPO4F and (K2-xCay(PO3F)a(PO4)b)]. This result suggested possible fluoride leaching from PTFE. Methods for repurposing PTFE are rare and involve harsh reaction conditions (30-32), so further investigation ensued. Ball milling PTFE with a K3PO4 activator (5 equiv) at 35 Hz for 3 hours in a PTFE-free milling device gave a powder PTFE-mix(KF), for which the water-soluble fraction was analysed by19F NMR spectroscopy (D2O). Signals at -120.6 ppm and -73.2 ppm (1JP-F = 867 Hz) were ascribed to F- (84%) and FPO32-(15%) respectively, and quantification indicated close to quantitative fluoride recovery. Alternative phosphate salt activators including K2HPO4, KH2PO4, KPO3, K5P3O10were slightly less effective with theexception of K4P2O7 that led to PTFE-mix(PF) composed unexpectedly of K2PO3F (99%) ( F = -73.7, 1JP-F = 867 Hz) and trace amount of KF (1%) ( F = -120.1 ppm). Replacing the steelcomponents (milling jar and balls) with zirconia gave similar results indicating that the phosphate salt activators are responsible for PTFE degradation; indeed, this control experiment excludes the possibility of metal leaching from the milling jar and balls. Remarkably high fluoride recovery as either KF or K2PO3F encouraged in-depth analysis and investigation.

[0217] NMR and Raman spectroscopy analysis gave further insights into the composition ofPTFE-mixes (Fig. 1B). Quantitative31P NMR spectroscopy confirmed the formation of PO3F2-(PTFE-mix(KF): P = 1.0, 1JP^F = 867 Hz, 12% P; PTFE-mix(PF): P = 1.5, 1JP^F = 867 Hz, 79% P) aswell as the presence of PO43-(PTFE-mix(KF): P = 2.7, 14% P; PTFE-mix(PF): P = 2.9, 14% P), P2O74-(PTFE-mix(KF): P = -6.3, 70% P; PTFE-mix(PF): P = -6.3, 3.0% P) and P3O105-(PTFE- mix(KF):P= -5.5, -20.3,2JP^P= 20 Hz, 4% P; PTFE-mix(P-F):P= -5.5, -19.5,2JP^P= 20 Hz, 4% P). The formation of pyro- and triphosphates indicates that the phosphate ions act as a nucleophile under mechanical activation (33-36). Quantitative13C NMR spectroscopy enabled the identification of the water-soluble carbon-containing components resulting from PTFE degradation. These include oxalate (C2O42-) (PTFE-mix(KF):C= 173.0, 2% C; PTFE-mix(P-F):C= 173.0, 1% C), formate (HCO2-) (PTFE-mix(KF): C = 171.1, 1% C), and predominantly carbonate(CO32-) (PTFE-mix(KF): C = 165.5, 48% C; PTFE-mix(P-F): C = 160.2, 7% C). Furthermore, CO2(20 mg, 42% C) was identified through gas capture analysis upon K4P2O7-mediated PTFE degradation; CO2was not detected with K3PO4as activator. Raman spectroscopy was performed next to identify the water-insoluble black material isolated from PTFE-mix(KF)and PTFE-mix(PF). For both materials, bands were observed at 1355 cm-1and 1579 cm-1, that are consistent with the disordered and graphitic bands of carbon (~ 45%) (37). Powder X-ray diffraction (PXRD) analysis confirmed the presence of K2PO3F in both PTFE-mix(KF)and PTFE-mix(PF), with no residual crystalline PTFE remaining. Solid-state NMR corroborated previous findings that PTFE- mix(KF)predominantly contained KF and K4P2O7, while PTFE-mix(PF)was mainly composed of K2PO3F.

[0218] Control experiments studied the stability of K3PO4 and K4P2O7 under milling conditions in the absence of PTFE. Both salts were found to be stable, although K3PO4 (3%) and K5P3O10 (2%) were formed as new species upon milling K4P2O7. Furthermore, the by-products K2CO3, K2C2O4, and K2PO3F formed upon treatment of PTFE under ball milling conditions were also capable of PTFE degradation under the standard milling conditions used, with K2CO3 being most effective (Fig.1C).

[0219] With a protocol to convert PTFE into KF and K2PO3F, the versatility of this new methodology was investigated. Activator screening

[0220] To a 15 mL stainless-steel milling jar was added two stainless-steel balls (7 g), PTFE (1 equiv.) and anhydrous activator to give 0.5 g of material for milling. The jar was closed and securely fitted to the mill which was set for 3 h at the frequency of 35 Hz. Upon completion, the jar was opened and the powder was collected.30-70 mg PTFE-mix and 10 mg sodium triflate asinternal standard were dissolved in 1.5 mL H2O in a 1.5 mL microcentrifuge tube and centrifuged for 15-30 min. An aliquot was analyzed with 90% H2O and 10% D2O in an NMR tube. The yield of KF and K2PO3F was determined by quantitative19F NMR spectroscopy.

[0221] The results are provided in Fig.2. Stoichiometry of activator K3PO4

[0222] The reaction was conducted in an analogous manner to the activator screening described hereinbefore, albeit with varying stoichiometries of K3PO4.

[0223] The results are provided in Fig.3. K4P2O7

[0224] The reaction was conducted in an analogous manner to the activator screening described hereinbefore, albeit with varying stoichiometries of K4P2O7.

[0225] The results are provided in Fig.4. K2CO3, Na2CO3, CaCO3and KHCO3

[0226] The reaction was conducted in an analogous manner to the activator screening described hereinbefore, albeit with varying stoichiometries of K2CO3, Na2CO3, CaCO3 and KHCO3. Screening for the optimal stoichiometry of K2CO3 for PTFE destruction revealed that 8 equiv. K2CO3enables close to quantitative fluoride release from PTFE under mechanochemical conditions (15 mL jar, 2x7 gr ball, 35 Hz, 3 h). Under these conditions, KF was obtained in 100%yield. Further screening with Na2CO3, CaCO3, KHCO3 demonstrated that these salts also reactwith PTFE for fluoride release, albeit less effectively than K2CO3. Indeed, under similar conditions, these three activators gave NaF in 40% yield, CaF2 in trace amount (< 5%), and KF also in trace amount (<1%), respectively.

[0227] The decomposition of PFAS other than PTFE was studied with K2CO3 (8 equiv) (15 mL jar, 2x7 gr ball, 35 Hz, 3 h). Polyvinylidene fluoride (PVDF), a key component of Li+batteries, was destroyed with 47% of its fluorine content recovered as KF, and harmful perfluorooctanoic acid (PFOA) was decomposed very effectively with KF formed in 95% yield.

[0228] The results are provided in Fig.5. K2C2O4 and Na2C2O4

[0229] The reaction was conducted in an analogous manner to the activator screening described hereinbefore, albeit with varying stoichiometries of K2C2O4. The reaction of PTFE,PVDF and PFOA with 10 equivalents of K2C2O4led to 37%, 71% and 44% fluoride release, respectively, as KF under mechanochemical conditions (15 mL jar, 2x7 gr ball, 35 Hz, 3 h). Under similar conditions, the destruction of PTFE with Na2C2O4was less effective affording NaF in 14% yield.

[0230] The results are provided in Fig.6. K2SiO3, Na2SiO3and Ca2SiO4

[0231] The reaction was conducted in an analogous manner to the activator screening described hereinbefore, albeit with different stoichiometries of K2SiO3. The reaction of PTFE with 5 equivalents of K2SiO3 resulted in quantitative fluoride recovery as KF under mechanochemical conditions (15 mL jar, 2x7 gr ball, 35 Hz, 3 h) along with SiO2as by-product. Furthermore, PVDF and PFOA reacted with K2SiO3(5 equiv) affording KF in 63% and 53%, respectively. Sodiumsilicate (Na2SiO3) and calcium silicate (Ca2SiO4) were also effective as demonstrated with PTFEaffording NaF and CaF2in 95% and 50% yield, respectively.

[0232] The results are provided in Fig.7. Na2O and Li2O

[0233] The reaction was conducted in an analogous manner to the activator screening described hereinbefore, albeit with different stoichiometries of Na2O. The reaction of PTFE with 5 equivalents of Na2O resulted in quantitative fluoride recovery as NaF (100%) under mechanochemical conditions (15 mL jar, 2x7 gr ball, 35 Hz, 3 h). Na2O (5 equiv) also enabled the destruction of PVDF and PFOA with concomitant formation of 97 % and 90%, respectively. The reaction of PTFE with Li2O was also effective resulting in the formation of LiF in yield exceeding 95%.

[0234] The results are provided in Fig.8. K2SO4, Na2SO4and CaSO4

[0235] The reaction was conducted in an analogous manner to the activator screening described hereinbefore, albeit with different stoichiometries of K2SO4. The reaction of PTFE with 10 equiv. of K2SO4led to 21% KF and 21% KSO3F under mechanochemical conditions (15 mL jar, 2x7 gr ball, 35 Hz, 3 h). With 5 equiv. of K2SO4, the process led to 19% of KF and 17% of KSO3F. The process was less suitable for generalisation as the application of this protocol (5 equiv of K2SO4) to PVDF and PFOA gave ~ 1% of KSO3F. Using PTFE, Na2SO4(5 equiv) was less effective (13% fluoride release as NaF) and no reaction occurred with CaSO4 (5 equiv).

[0236] The results are provided in Fig.9.PFAS screening

[0237] A broad range of polymeric (1 and 4-7) and non-polymeric PFAS chemicals (13-27), as well as various materials including PVF film (8), FEP film (9), ECTFE film (10), PFA tubing (11), PTFE seal (2), PTFE tape (3), and mixture of polypropylene and PTFE (12) underwent highly efficient degradation (Fig. 10A). Such generality encouraged the development of a robust strategy to isolate commonly used fluorinating reagents derived from PTFE-mix(KF) and PTFE- mix(PF). A simple extractive protocol consisting of treating PTFE-mix(KF) with H2O and MeOH / EtOH enabled the isolation of KFPTFEin 64% yield and the recovery of byproduct salts, which could be recycled as activators for converting PTFE into K2PO3F. Alternatively, the reaction of PTFE- mix(PF) consisting mainly of K3PO3F with the tetramethylammonium hydroxide afforded tetramethylammonium fluoride (TMAF, 81%) (38), as well as its tert-amyl alcohol complex[TMAF (tAmylOH)] (quant. yield), a fluorinating reagent well documented for nucleophilicaromatic fluorination (SNAr) (39). The bench stable reagent tetrabutylammonium tetra(tert-butylalcohol) fluoride [TBAF (tBuOH)4] was prepared in a similar manner and isolated in 50% yield(40) (Fig.10B). Synthesis of diverse fluorochemicalsThe reactivity of these PTFE-derived fluorinating reagents [KF, TMAF, TMAF (tAmylOH) andTBAF (tBuOH)4] was tested in the syntheses of diverse fluorochemicals. PTFE-derived KF(KFPTFE) performed comparably to commercial KF (KFComm) in the fluorination of 2,4- dinitrochlorobenzene and enabled efficient fluorination towards PhBF3K (87%) and 4- CHOC6H4BF3K (93%) (41), 2-fluoro-5-nitrobenzonitrile (29), methyl 2-fluoroisobutyrate (34), dimethylsulfamoyl fluoride (37, electrolyte), PyFluor (35, deoxyfluorinating reagent), and SulfoxFluor (36, deoxyfluorinating reagent) (Fig.10C). Notably, PTFE-mix(KF) itself, produced from the reaction of PTFE with K3PO4, could be directly employed as an efficient fluorination reagent in the synthesis of sulfonyl fluorides (35-37). The copper-mediated reaction (42) of KFPTFEwith 4-CHOC6H4BF3K afforded 4-fluorobenzaldehyde (30), the building block used in the synthesis of Lipitor. Tetraalkylammonium fluoride reagents prepared from PTFE-mix(PF)were successfully employed in the syntheses of 4-fluoronitrobenzene (28), 2-chloro-1-fluoro-4-nitrobenzene (31), 2,6-difluorobenzonitrile (32), and methyl 2-fluoropropanoate (33). These fluorochemicals are essential building blocks in the synthesis of various organo-fluorine containing compounds, including the pharmaceuticals Cabozantinib (anti-cancer medication), (+)-SJ733 (anti-malaria agent), Lipitor (cholesterol-lowering), Dacomitinib (lung carcinoma), Rufinamide (seizure disorders), as well as the agrochemicals Indaziflam (preemergent herbicide) and Triaziflam (herbicide) (Fig.10C).Phosphate activator recovery and recycling

[0238] General Procedure outlined in Fig. 12: To n 15 mL stainless-steel milling jars, two chrome steel balls (2 × 7 g), PTFE (1 equiv., 86 mg) and K3PO4(0.625 equiv. / F, 457 mg) or [P]Recov(mixture of recovered activator salts ^ 457 mg) were added. The jars were sealed and securely fitted to a mill which was set for 6 h at a frequency of 35 Hz. Upon completion, the jars were opened. An aliquot of PTFE-mix* (~20-30 mg) spiked with sodium triflate (~10 mg, as internal standard) was extracted with D2O (10 atom% D), centrifugated for 15^30 minutes and the supernatant analysed by quantitative19F-NMR spectroscopy.

[0239] The obtained n jars of PTFE-mix were extracted with H2O (~20 mL per jar) and combined. The resulting suspension was centrifugated for 10 min to sediment water-insoluble carbon black. The resulting clear supernatant was decanted and concentrated to 5 mL under reduced pressure. KOH (1 equiv. / P^F*, as determined by quantitative19F-NMR spectroscopy) was added and the solution heated at reflux for 10 h until no PO3F2was detected by quantitative19F-NMR spectroscopy. MeOH (10^20 mL per jar) was added and the reaction placed in an ultrasonic bath for 1.5 h. The supernatant was decanted and collected, while the remaining solid was further extracted with H2O (~0.3 mL per jar) and MeOH (10^20 mL per jar) and further subjected to 1.5 h of ultrasonic activation. All extracts were combined and centrifugated for 10 min, leading to the sedimentation of an insoluble activator salt residue KxH3-xPO4(a). The clear supernatant was then decanted and concentrated under reduced pressure to afford crude KF. Crude KF was further purified by suspension in MeOH:EtOH (6:1, ~3 mL per jar) and placed in an ultrasonic bath for 30 min, followed by centrifugation for 10 min leading to the precipitation of insoluble salts. The clear supernatant was decanted and the solvent removed in vacuo to afford KF (b).

[0240] To the insoluble activator salt residue (a), H2O (2.5 mL per jar) and KOH (1.8 equiv. / P^ F*, as determined by quantitative19F-NMR spectroscopy) were added to adjust the pH to 14 before the mixture was dried under reduced pressure. The resulting residue was further dried in vacuo with further heating for 12 h to afford a mixture of recovered phosphate salts (e.g., K3PO4CYC), which could be reused as an activator for pulverising a per- or polyfluoroalkyl compound. K3PO4CYCwas analysed by quantitative31P-NMR, quantitative19F-NMR and13C-NMR spectroscopy in D2O (10 atom% D) using triethyl phosphate, sodium triflate and potassium acetate as internal standards, respectively.

[0241] The results are provided in Fig.11. Silicate activator screening

[0242] Additional examples following similar procedures to those outlined above were

[0243] To a 15 mL stainless-steel milling jar was added two hardened chrome steel bearings (2 × 7 g), PTFE (1 equiv.) and pre-dried silicate-based activator (5 equiv. per C2F4) according to the scheme illustrated in FIG.15. The total loading of material in the jar (PTFE and activator) was kept constant at 500 mg. The jar was closed and securely fitted to the mill which was set for 3 h at a frequency of 35 Hz. Upon completion, the jar was opened and the powder was collected. An aliquot of PTFE-mix (10-30 mg) and sodium triflate (10 mg, as internal standard) was extracted with D2O (10 atom% D), centrifugated for 15-30 min and analysed by quantitative19F-NMR spectroscopy. Then, the NMR sample was transferred back to the sample preparation vial, KOH (0.1 mL, 10 M) was added and the mixture was kept still for 6 h and analysed by quantitative19F- NMR spectroscopy for the Si-F release analysis.

[0244] Yields were determined by quantitative 19F-NMR spectroscopy in D2O (10 atom% D) using sodium triflate as internal standard and are illustrated in FIG.13. Isolation of KF from PFAS-mixSi

[0245] To a 15 mL stainless-steel milling jar was added two chrome steel balls (2 x 7 g), PTFE (1 equiv., 57 mg) and K2SiO3 (5.0 equiv., 443 mg) according to the scheme illustrated in FIG.16. The jars were closed and securely fitted to a mill which was set for 3 h at a frequency of 35 Hz. Upon completion, the jars were opened, the powder was collected and extracted with H2O (20 mL). The resulting suspension was centrifuged for 30 min to eliminate water-insoluble carbon black. The resulting clear supernatant was decanted and concentrated under reduced pressure to obtain a solid residue, which was sonicated with MeOH (6 mL) for 30 min and centrifugated for another 30 min. The clear supernatant was decanted and concentrated under reduced pressure to give KF (108 mg) in 78% yield (95% purity determined by quantitative19F NMR spectroscopy). Isolation of NaF from PFAS-mixSi

[0246] To three 15 mL stainless-steel milling jars was added two chrome steel balls (2 x 7 g), PTFE (1 equiv., 70 mg) and Na2SiO3 (5.0 equiv., 430 mg) each according to the scheme illustrated in FIG.17. The jars were closed and securely fitted to a mill which was set for 3 h at a frequency of 35 Hz. Upon completion, the jars were opened, the powder was collected and extracted with H2O (40 mL). The resulting suspension was centrifuged for 30 min at room temperature to eliminate water-insoluble carbon black. The resulting clear supernatant was decanted and concentrated under reduced pressure to afford a solid residue. This residue was treated with aqueous NaOH (10 mL, 0.5 g / mL) and heated for 5 min using a heat gun to facilitate dissolution. The solution was then allowed to cool to room temperature and stand for 30 minutes,resulting in the precipitation of sodium fluoride (NaF). The supernatant was decanted, and the remaining solid was washed with MeOH (3 × 10 mL) to remove residual NaOH. The resulting solid was dried under vacuum to yield pure NaF (277 mg) in 73% yield (93% purity determined by quantitative19F NMR spectroscopy). Summary

[0247] The inventors have shown that PFAS are viable fluorine sources for the synthesis of high-value fluorochemicals by applying a regenerative, operationally simple and mild activator- enabled mechanochemical process. The protocol which enables the breakdown of PFAS into either KF or K2PO3F is applicable to a wide range of PFAS including polymeric materials such as PTFE and PVDF, as well as harmful non-polymeric PFOA and PFOS, using a variety of activators. Several commonly used nucleophilic fluorinating reagents can now be produced from PFAS for the synthesis of building blocks of agrochemicals, pharmaceuticals, and materials. The process of the present invention therefore represents an innovative solution to PFAS management as it allows for the upcycling of harmful PFAS waste with safe and circular fluorochemical industry in mind.

[0248] While specific embodiments of the invention have been described herein for the purpose of reference and illustration, various modifications will be apparent to a person skilled in the art without departing from the scope of the invention as defined by the appended claims.REFERENCES 1. M. M. Ginty, C. Lindwall, ^Forever Chemicals^ Called PFAS Show Up in Your Food, Clothes, and Home, (NRDC, 2023), https: / / www.nrdc.org / stories / forever-chemicals-called-pfas- show-your-food-clothes-and-home. 2. P. Dewapriya, S. Nilsson, S. Ghorbani Gorji, J. W. O^Brien, J. Bräunig, M. J. Gómez Ramos, E. Donaldson, S. Samanipour, J. W. Martin, J. F. Mueller, S. L. Kaserzon, K. V. Thomas, Novel Per- and Polyfluoroalkyl Substances Discovered in Cattle Exposed to AFFF-Impacted Groundwater. Environ. Sci. Technol.57, 13635^13645 (2023). 3. T. D. Hoskins, R. W. Flynn, G. S. M. Coogan, A. C. Catlin, C. de Perre, M. M. Gharehveran, Y. J. Choi, L. S. Lee, J. T. Hoverman, M. S. Sepúlveda, Chronic Exposure to a PFAS Mixture Resembling AFFF-Impacted Surface Water Decreases Body Size in Northern Leopard Frogs (Rana pipiens), Environ. Sci. Technol.57, 14797^14806 (2023). 4. A. T. Mikkonen, J. Martin, R. N. Upton, A. O. Barker, C. M. Brumley, M. P. Taylor, L. Mackenzie, M. S. Roberts, Spatio-temporal trends in livestock exposure to per- and polyfluoroalkyl substances (PFAS) inform risk assessment and management measures, Environ. Res.225, 115518 (2023). 5. ^DuPont, 3M Concealed Evidence of PFAS Risks^ (UCS, 2019), https: / / www.ucsusa.org / resources / dupont-3m-concealed-evidence-pfas-risks. 6. A. K. Ilango, T. Jiang, W. Zhang, M. N. Pervez, J. I. Feldblyum, H. Efstathiadis, Y. Liang, Enhanced Adsorption of Mixtures of Per- and Polyfluoroalkyl Substances in Water by ChemicallyModified Activated Carbon, ACS EST Water, 3, 3708 3715 (2023).7. A. Maimaiti, S. Deng, P. Meng, W. Wang, B. Wang, J. Huang, Y. Wang, G. Yu, Competitive adsorption of perfluoroalkyl substances on anion exchange resins in simulatedAFFF-impacted groundwater, Chem. Eng. J. 348, 494 502 (2018).8. M. Ateia, A. Alsbaiee, T. Karanfil, W. Dichtel, Efficient PFAS Removal by Amine- Functionalized Sorbents: Critical Review of the Current Literature, Environ. Sci. Technol. Lett.6,688 695 (2019).9. J. N. Meegoda, B. B. de Souza, M. M. Casarini, J. A. Kewalramani, A Review of PFAS Destruction Technologies, Int. J. Environ. Res. Public Health, 19, 16397 (2022). 10. N. Merino, Y. Qu, R. A. Deeb, E. L. Hawley, M. R. Hoffmann, S. Mahendra, Degradation and Removal Methods for Perfluoroalkyl and Polyfluoroalkyl Substances in Water, Environ. Eng. Sci.33, 615^649 (2016). 11. S. Verma, T. Lee, E. Sahle-Demessie, M. Ateia, M. N. Nadagouda, Recent advances on PFAS degradation via thermal and nonthermal methods, Chem. Eng. J. Adv.13, 100421 (2023). 12. J. Cui, P. Gao, Y. Deng, Destruction of Per- and Polyfluoroalkyl Substances (PFAS) with Advanced Reduction Processes (ARPs): A Critical Review, Environ. Sci. Technol. 54,3752 3766 (2020).13. P. Roesch, C. Vogel, F.-G. Simon, Reductive Defluorination and Mechanochemical Decomposition of Per- and Polyfluoroalkyl Substances (PFASs): From Present Knowledge to Future Remediation Concepts, Int. J. Environ. Res. Public Health, 17, 7242 (2020). 14. Q. Khan, M. Sayed, J. A. Khan1, F. Rehman, S. Noreen, S. Sohni, I. Gul, Advanced oxidation / reduction processes (AO / RPs) for wastewater treatment, current challenges, and future perspectives: a review, Environ. Sci. Pollu. R.31, 1863^1889 (2024). 15. J. Qu, X. He, Q. Zhang, X. Liu, F. Saito, Decomposition pathways of polytetrafluoroethylene by co-grinding with strontium / calcium oxides, Environ. Technol. 38, 1421^1427 (2017). 16. J. Lee, Q. Zhang, F. Saito, Mechanochemical Synthesis of Lanthanum Oxyfluoride byGrinding Lanthanum Oxide with Poly(vinylidene fluoride), Ind. Eng. Chem. Res. 40, 4785 4788(2001). 17. N. Yang, S. Yang, Q. Ma, C. Beltran, Y. Guan, M. Morsey, E. Brown, S. Fernando, T. M. Holsen, W. Zhang, Y. Yang, Solvent-Free Nonthermal Destruction of PFAS Chemicals and PFASin Sediment by Piezoelectric Ball Milling, Environ. Sci. Technol. Lett. 10, 198 203 (2023).18. G. Cagnetta, Q. Zhang, J. Huang, M. Lu, B. Wang, Y. Wang, S. Deng, G. Yu, Mechanochemical destruction of perfluorinated pollutants and mechanosynthesis of lanthanum oxyfluoride: A Waste-to-Materials process, Chem. Eng. J.316, 1078^1090 (2017). 19. K. Zhang, J. Huang, G. Yu, Q. Zhang, S. Deng, B. Wang, Destruction of Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoic Acid (PFOA) by Ball Milling, Environ. Sci. Technol.47,6471 6477 (2013).20. Q. Zhang, J. Lu, F. Saito, M. Baron, Mechanochemical Solid-Phase Reaction between Polyvinylidene Fluoride and Sodium Hydroxide, J. Appl. Polym. Sci.81, 2249^2252 (2001). 21. M. Ateia, L. P. Skala, A. Yang, W. R. Dichtel, Product analysis and insight into the mechanochemical destruction of anionic PFAS with potassium hydroxide, J. Hazard. Mater. Adv. 3, 100014 (2021). 22. United States Environmental Protection Agency, ^Per- and Polyfluoroalkyl Substances (PFAS): Incineration to Manage PFAS Waste Streams^ (2020): https: / / www.epa.gov / sites / default / files / 2019- 09 / documents / technical_brief_pfas_incineration_ioaa_approved_final_july_2019.pdf. 23. A. Berhanu, I. Mutanda, T. Ji, M. A. Qaria, B. Yang, D. Zhu, A review of microbial degradation of per- and polyfluoroalkyl substances (PFAS): Biotransformation routes and enzymes, Sci. Total Environ.859, 160010 (2023). 24. B. Trang, Y. Li, X. S. Xue, M. Ateia, K. N. Houk, W. R. Dichtel, Low-temperature mineralization of perfluorocarboxylic acids, Science 377, 839^845 (2022).25. S. L. James, C. J. Adams, C. Bolm, D. Braga, P. Collier, T. Fri^ i , F. Grepioni, K. D. M.Harris, G. Hyett, W. Jones, A. Krebs, J. Mack, L. Maini, A. G. Orpen, I. P. Parkin, W. C.Shearouse, J. W. Steedk, D. C. Waddell, Mechanochemistry: opportunities for new and cleaner synthesis, Chem. Soc. Rev.41, 413^447 (2012). 26. J. Fang, S. Li, T. Gu, A. Liu, R. Qiu, W.Zhang, Treatment of per- and polyfluoroalkyl substances (PFAS): A review of transformation technologies and mechanisms, J. Environ. Chem. Eng.12, 111833 (2024). 27. O. C. Olatunde, A. T. Kuvarega, D. C. Onwudiwe, Photo enhanced degradation of polyfluoroalkyl and perfluoroalkyl substances, Heliyon 6, e05614 (2020). 28. M. Umar, Reductive and Oxidative UV Degradation of PFAS^Status, Needs and Future Perspectives, Water 13, 3185 (2021). 29. C. Patel, E. André-Joyaux, J. A. Leitch, X. M. de Irujo-Labalde, F. Ibba, J. Struijs, M. A. Ellwanger, R. Paton, D. L. Browne, G. Pupo, S. Aldridge, M. A. Hayward, V. Gouverneur, Fluorochemicals from fluorspar via a phosphate-enabled mechanochemical process that bypasses HF, Science 381, 302^306 (2023). 30. J. Lee, Q. Zhang, F. Saito, Synthesis of nano-sized lanthanum oxyfluoride powders by mechanochemical processing, J. Alloys Compd.348, 214^219 (2003). 31. D. J. Sheldon, J. M. Parr, M. R. Crimmin, Room Temperature Defluorination of Poly(tetrafluoroethylene) by a Magnesium Reagent, J. Am. Chem. Soc. 145, 10486^10490 (2023). 32. B. Ame´duri, H. Hori, Recycling and the end of life assessment of fluoropolymers: recent developments, challenges and future trends, Chem. Soc. Rev.52, 4208^4247 (2023). 33. C. T. Walsh, Phosphorylases: Inorganic Phosphate as Oxygen Nucleophile. The Chemical Biology of Phosphorus, The Royal Society of Chemistry, (2020). 34. G. K. S. Prakash, H. Vaghoo, C. Panja, V. Surampudi, R. Kultyshev, T. Mathew, G. A. Olah, Effect of carbonates / phosphates as nucleophilic catalysts in dimethylformamide for efficient cyanosilylation of aldehydes and ketones, PNAS, 104, 3026^3030 (2007). 35. T. Dalidovich, K. A. Mishra, T. Shalima, M. Kudrja^ova, D. G. Kananovich, R. Aav, Mechanochemical Synthesis of Amides with Uronium-Based Coupling Reagents: A Method for Hexa-amidation of Biotin[6]uril, ACS Sustainable Chem. Eng.8, 15703^15715 (2020). 36. F. Zhai, T. Xin, M. B. Geeson, C. C. Cummins, Sustainable Production of Reduced Phosphorus Compounds: Mechanochemical Hydride Phosphorylation Using Condensed Phosphates as a Route to Phosphite, ACS Cent. Sci.8, 332^339 (2022). 37. M. Saravanan, M. Ganesan, S. Ambalavanan, An in situ generated carbon as integrated conductive additive for hierarchical negative plate of lead-acid battery, J. Power Sources, 251, 20^29 (2014). 38. V. Iashin, T. Wirtanen, J. E. Perea-Buceta, Tetramethylammonium Fluoride: Fundamental Properties and Applications in C-F Bond-Forming Reactions and as a Base, Catalysts, 12, 233 (2022).39. M. T. Morales-Colón, Y. Y. See, S. J. Lee, P. J. H. Scott, D. C. Bland, M. S. Sanford,Tetramethylammonium Fluoride Alcohol Adducts for SNAr Fluorination, Org. Lett. 23, 4493 4498(2021). 40. D. W. Kim, H. J. Jeong, S. T. Lim, M. H. Sohn, Tetrabutylammonium tetra(tert-butyl alcohol)-coordinated fluoride as a facile fluoride source, Angew. Chem. Int. Ed. 47, 8404^8406 (2008). 41. A. J. J. Lennox, G. C. Lloyd-Jones, Preparation of Organotrifluoroborate Salts: Precipitation-Driven Equilibrium under Non-Etching Conditions, Angew. Chem. Int. Ed.51, 9385^ 9388 (2012). 42. Y. Ye, S. D. Schimler, P. S. Hanley and M. S. Sanford, Cu(OTf)2-mediated fluorination of aryltrifluoroborates with potassium fluoride, J. Am. Chem. Soc.135, 16292^16295 (2013).

Claims

Claims 1. A process comprising the step of pulverising together a per- or polyfluoroalkyl compound and an activator, wherein the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal.

2. The process of claim 1, wherein the step of pulverising is conducted in a ball mill, a resonant acoustic mixer, a pestle and mortar or a twin screw extruder.

3. The process of claim 1 or 2, wherein the pulverising step results in the degradation of C-F bonds.

4. The process of any one of claims 1, 2 or 3, wherein the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (I):wherein R1is H, halo, (1-3C)haloalkyl or (1-3C)haloalkoxy.

5. The process of claim 4, wherein R1 is H, F, Cl, CH2F, CF2H, CF3 or OCF3.

6. The process of any one of the preceding claims, wherein the per- or polyfluoroalkyl compound comprises a moiety having the structure of Formula (Ib):wherein R1, R2 and R3 are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy.

7. The process of claim 6, wherein R1, R2and R3are each independently selected from H, F, Cl and CF3.

8. The process of any one of the preceding claims, wherein the per- or polyfluoroalkyl compound comprises a moiety having any one of the following structures:

9. The process of any one of the preceding claims, wherein the per- or polyfluoroalkyl compound is a polymer.

10. The process of claim 9, wherein the polymer comprises a monomeric repeating unit having the structure of Formula (IIb):wherein R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy.

11. The process of claim 10, wherein: (i) R1, R2and R3are F; (ii) R1 is F, and R2 and R3 are H; (iii) R1is F, R2is F and R3is Cl; (iv) R1 is CF3, and R2 and R3 are F; or (v) R1, R2 and R3 are H.

12. The process of any one of the preceding claims, wherein the per- or polyfluoroalkyl compound is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP or PP-PTFE.

13. The process of any one of the preceding claims, wherein the activator is: (i) a phosphate, monosulfate, carbonate, oxalate, silicate or oxide of a group I metal; or (ii) a carbonate or silicate of a group II metal.

14. The process of any one of the preceding claims, wherein the activator is selected from: (i) M2HPO4, MH2PO4, M3PO4, MPO3, M2PO3F, M4P2O7, M5P3O10, M2SO4, M2CO3, M2C2O4, MHCO3, M2SiO3and M2O, wherein M is a group I metal; or (ii) M^HPO4, M^(H2PO4)2, M^CO3and M^2SiO4, wherein M^ is a group II metal.

15. The process of any one of the preceding claims, wherein the activator is selected from: (i) M2HPO4, M3PO4, M4P2O7, M2CO3, M2SiO3and M2O, wherein M is a group I metal; or (ii) M^2SiO4, wherein M^ is a group II metal.

16. The process of claim 14 or 15, wherein the group I metal (i.e., M) Na or K.

17. The process of any one of claims 14, 15 or 16, wherein the group II metal (i.e., M^) is Ca.

18. The process of any one of the preceding claims, wherein the activator is K2HPO4, KH2PO4, K3PO4, Na3PO4, Li3PO4, KPO3, K4P2O7, Na4P2O7 K5P3O10, NaPO3, CaHPO4, Ca(H2PO4)2, K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4, Na2CO3, K2PO3F, KHCO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O.

19. The process of any one of the preceding claims, wherein the activator is K3PO4, Na3PO4, K4P2O7, K2CO3, K2SiO3, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O.

20. The process of any one of the preceding claims, wherein the activator is K3PO4 or K4P2O7.

21. The process of any one of the preceding claims, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 0.25-2.5 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound.

22. The process of any one of the preceding claims, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 1-1.4 equivalents of the activator are pulverised together with 1 equivalent of the per- or polyfluoroalkyl compound.

23. The process of any one of the preceding claims, wherein the process comprises the following steps: I. pulverising together a per- or polyfluoroalkyl compound and an activator, wherein the activator is a phosphate, sulfate, carbonate, oxalate, silicate or oxide of a group I or group II metal (e.g., a phosphate of a group I or group II metal); II. forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together; and III. pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts.

24. The process of claim 23, wherein the step of forming a mixture of recovered activator salts once the per- or polyfluoroalkyl compound and the activator have been pulverised together comprises extracting an insoluble activator salt residue from the reaction mixture.

25. The process of claim 24, wherein the insoluble activator salt residue is treated with H2O and KOH to form a mixture of recovered activator salts.

26. The process of claim 23, 24 or 25, wherein the activator is a phosphate of a group I metal and the mixture of recovered activator salts comprises phosphates of the group I metal.

27. The process of any one of claims 23-26, wherein the activator is K3PO4 and the mixture of recovered activator salts comprises K3PO4and / or K4P2O7.

28. The process of any one of claims 23-27, wherein the step of pulverising together a per- or polyfluoroalkyl compound and the mixture of recovered activator salts results in a mixture comprising at least one fluorinated species.

29. The process of any one of the preceding claims, wherein the step of pulverising together the per- or polyfluoroalkyl compound and the activator results in a mixture comprising at least one fluorinated species.

30. A mixture comprising one or more fluorinated species obtainable by the process of claim 28 or 29.

31. Use of the mixture of claim 30 as a fluorinating agent.

32. A method of synthesizing an organofluorine-derived fluorinated inorganic salt, the method comprising: providing an organofluorine; providing an activator; and combining the organofluorine with the activator to yield the organofluorine-derived fluorinated inorganic salt.

33. A method of synthesizing a fluorinated compound, the method comprising: combining an organofluorine with an activator to yield an organofluorine-derived fluorinated inorganic salt; and reacting the organofluorine-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

34. The method of claim 32 or 33, wherein the organofluorine comprises a fluoropolymer and / or a per- or poly- fluorinated alkyl substance (PFAS).

35. The method of any one of claims 32-24, wherein the organofluorine-derived fluorinated inorganic salt comprises a perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt, a polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt,a polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt, a fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt, an ethylene tetrafluoroethylene (ETFE)-derived fluorinated inorganic salt, a perfluorooctanoic acid (PFOA)-derived fluorinated inorganic salt, and / or a perfluorooctane sulfonic acid (PFOS)-derived fluorinate inorganic salt.

36. A method of synthesizing a perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt, the method comprising: providing a perfluoroalkoxy alkane (PFA); providing an activator; andcombining the perfluoroalkoxy alkane (PFA) with the activator to yield the perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt.

37. A method of synthesizing a fluorinated compound, the method comprising: combining a perfluoroalkoxy alkane (PFA) with an activator; and reacting the perfluoroalkoxy alkane (PFA)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

38. A method of synthesizing a polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt, the method comprising: providing a polytetrafluoroethylene (PTFE); providing an activator; and combining the polytetrafluoroethylene (PTFE) with the activator to yield the polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt.

39. A method of synthesizing a fluorinated compound, the method comprising: combining a polytetrafluoroethylene (PTFE) with an activator; and reacting the polytetrafluoroethylene (PTFE)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

40. A method of synthesizing a fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt, the method comprising: providing a fluorinated ethylene propylene (FEP); providing an activator; and combining the fluorinated ethylene propylene (FEP) with the activator to yield the fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt.

41. A method of synthesizing a fluorinated compound, the method comprising: combining a fluorinated ethylene propylene (FEP)with an activator; and reacting the fluorinated ethylene propylene (FEP)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

42. A method of synthesizing a polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt, the method comprising: providing a polyvinylidene difluoride (PVDF); providing an activator; andcombining the polyvinylidene difluoride (PVDF) with the activator to yield the polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt.

43. A method of synthesizing a fluorinated compound, the method comprising: combining a polyvinylidene difluoride (PVDF) with an activator; and reacting the polyvinylidene difluoride (PVDF)-derived fluorinated inorganic salt with a reagent, thereby fluorinating the reagent to yield the fluorinated compound.

44. The method of any one of claims 32-43, wherein the activator comprises a strong base.

45. The method of claim 44, wherein the strong base comprises LiOH, NaOH, KOH, and / or CsOH.

46. The method of claim 45, wherein the activator is NaOH or KOH.

47. The method of claim 46, wherein the activator is NaOH.

48. The method of claim 46, wherein the activator is KOH.

49. The method of any one of claims 32-48, further comprising activating the activator by application of mechanical force during the combining and / or reacting.

50. The method of claim 49, wherein the mechanical force is applied at least in part using a ball mill, a resonant acoustic mixer, a pestle and mortar, a high-shear mixing system, and / or a twin screw extruder.

51. The method of any one of claims 32-34 or 44-50, wherein the organofluorine comprises a moiety having the structure of Formula (I):wherein R1is H, halo, (1-3C)haloalkyl or (1-3C)haloalkoxy.

52. The method of claim 51, wherein R1 is H, F, Cl, CH2F, CF2H, CF3 or OCF3.

53. The method of any one of claims 51-52, wherein organofluorine comprises a moiety having the structure of Formula (Ib):wherein R1, R2and R3are each independently selected from H, halo, (1-3C)haloalkyl and (1- 3C)haloalkoxy.

54. The method of claim 53, wherein R1, R2 and R3 are each independently selected from H, F, Cl and CF3.

55. The method of any one of claims 51-54, wherein the organofluorine comprises a moiety having any one of the following structures:

56. The method of any one of claims 32-24 or 44-55, wherein the organofluorine is PTFE, PVDF, PCTFE, ETFE, PVDF-HFP, PVF, FEP, PFOA, PFOS or PP-PTFE.

57. The method of any one of claims 32-56, wherein the activator comprises: (i) a phosphate, monosulfate, carbonate, oxalate, silicate or oxide of a group I metal; or (ii) a carbonate or silicate of a group II metal.

58. The method of any one of claims 32-57, wherein the activator comprises a compound selected from: (i) M2HPO4, MH2PO4, M3PO4, MPO3, M2PO3F, M4P2O7, M5P3O10, M2SO4, M2CO3, M2C2O4, MHCO3, M2SiO3 and M2O, wherein M is a group I metal; or (ii) M^HPO4, M^(H2PO4)2, M^CO3 and M^2SiO4, wherein M^ is a group II metal.

59. The method of any one of claims 32-58, wherein the activator is selected from: (i) M2HPO4, M3PO4, M4P2O7, M2CO3, M2SiO3 and M2O, wherein M is a group I metal; or (ii) M^2SiO4, wherein M^ is a group II metal.

60. The method of claim 58 or 59, wherein the group I metal (i.e., M) is Na or K.

61. The method of any one of claims 58-60, wherein the group II metal (i.e., M^) is Ca.

62. The method of any one of claims 32-61, wherein the activator comprises K2HPO4, KH2PO4, K3PO4, Na3PO4, Li3PO4, KPO3, K4P2O7, Na4P2O7 K5P3O10, NaPO3, CaHPO4, Ca(H2PO4)2, K2SO4, Na2SO4, K2CO3, CaCO3, K2C2O4, Na2CO3, K2PO3F, KHCO3, K2SiO3, Na2C2O4, Na2SiO3, Li2SiO3, Ca2SiO4, Na2O or Li2O.

63. The method of any one of claims 32-62, wherein the activator comprises K3PO4, Na3PO4, K4P2O7, K2CO3, K2SiO3, Na2SiO3, Li2SiO3, Ca2SiO4, SiO2, Na2O or Li2O.

64. The method of any one of claims 32-63, wherein the activator comprises K3PO4or K4P2O7.

65. The method of any one of claims 32-64, wherein the activator is SiO2, K3PO4or K4P2O7.

66. The method of any one of claims 32-65, wherein for each C-F bond present in the organofluorine, 0.25-2.5 equivalents of the activator are combined with 1 equivalent of the organofluorine.

67. The method of claim 66, wherein for each C-F bond present in the per of polyfluoroalkyl compound, 1-1.4 equivalents of the activator are combined with 1 equivalent of the organofluorine.

68. The method of any one of claims 32-67, wherein the organofluorine is or comprises an industrial waste-product.

69. The method of any one of claims 32-68, wherein the organofluorine-derived fluorinated inorganic salt is or comprises an alkali metal fluoride.

70. The method of claim 69, wherein the alkali metal fluoride comprise LiF, NaF, and / or KF.

71. The method of claim 69 or 70, wherein the alkali metal fluoride is LiF.

72. The method of claim 69 or 70, wherein the alkali metal fluoride is NaF.

73. The method of claim 69 or 70, wherein the alkali metal fluoride is KF.

74. The method of any one of claims 32-73, wherein the organofluorine-derived fluorinated inorganic salt is comprised in a resulting mixture which comprises at least 1 ppm of the organofluorine.

75. The method of any one of claims 32-74, comprising fluorinating a reagent comprising at least one leaving group using the organofluorine-derived fluorinated inorganic salt to yield a fluorinated product.

76. The method of claim 75, wherein the fluorinated product comprises an organo-fluorine compound which is different from the organofluorine from which the fluorinated inorganic salt was derived.

77. The method of claim 75, wherein the fluorinated product comprises a recycled or remanufactured product of the organofluorine from which the fluorinated inorganic salt was derived.

78. The method of claim 75 or 76, wherein the fluorinated product comprises an alkyl fluoride and / or an aromatic fluoride.

79. The method of any one of claims 32-74 or 77, wherein the organofluorine is a commercial grade product produced in excess.

80. The method of any one of claims 49-79, wherein the organofluorine and / or the activator are comprised in a solution and / or a liquid suspension when the mechanical force is applied.

81. The method of any one of claims 49-80, wherein the mechanical force is applied using a sonicator.

82. The method of any one of claims 49-81, wherein the organofluorine comprises a mixture of two or more different fluorinated polymers (e.g., wherein the organofluorine comprises at least two, at least three, or at least four different fluorinated polymers).

Images