Processes and apparatus for converting poly- and perfluoroalkyl materials

Abstract

A process and apparatus for converting poly and perfluoroalkyl substances (PFAS). The PFAS is oxidized to a fluoride species using an oxidation reaction zone, preferably a thermal oxidation apparatus. The reaction zone is provided having at least one reactor containing a solid reactant for neutralizing the fluoride species. The solid reactant is also configured to decompose any remaining PFAS in the effluent from the oxidation zone. A cooling zone, such as a quenching zone, may be located between the reaction zone and the oxidation zone. The PFAS may be liquid PFAS injected into the thermal oxidation apparatus.

Description

Technical Field

[0001] (Related Application) This application claims priority to U.S. Non-Provisional Patent Application No. 18 / 586,776, filed Feb. 26, 2024, which claims priority to U.S. Provisional Patent Application No. 63 / 494,700, filed Apr. 6, 2023, the entire contents of which are incorporated herein by reference.

[0002] (Field of the Invention) The present invention generally relates to processes and apparatuses for removing and decomposing perfluoroalkyl substances.

Background Art

[0003] Perfluoroalkyl substances (PFAS) are highly stable "forever chemicals" that persist in the environment. PFAS has been associated with harmful effects on the kidneys, liver, blood, and immune system. Examples of PFAS are surfactants in industrial and consumer products such as fire-fighting foams, alkaline cleaners, paints, non-stick cooking utensils, carpets, interior decorations, shampoos, floor abrasives, smoke suppressants, semiconductors, photographic films, pesticide formulations, food packaging, masking tapes, and denture cleaners. The EPA has a list of over 179 PFAS that are toxic.

[0004] Typical PFAS concentrations are in the range of pg / L to ng / L. Currently, the EPA recommends a maximum limit of less than 70 ppt of PFAS, but more stringent EPA regulations and limits are being proposed. Therefore, continuous improvement of PFAS is needed.

[0005] While it is known that adsorbents can be used to adsorb and remove PFAS from rivers, the possibility of adsorbed PFAS leaching into the environment from discarded adsorbents remains. Degrading PFAS by treating contaminated materials is also known. Since PFAS are likely effective for their intended purpose, but limited in quantity, it is desirable to provide methods for the effective and efficient removal and degradation of PFAS. [Overview of the Initiative]

[0006] This invention provides for the removal and decomposition of PFAS. PFAS can be oxidized in a thermal oxidation apparatus and then decomposed in a mineralization reactor. Mineralization reduces the opportunity for the release of light fluorinated hydrocarbons or other components from the oxidation of PFAS. Furthermore, the mineralization reactor neutralizes the fluoride species produced by the oxidation.

[0007] The process of the present invention can be used with liquid PFAS and allows the flow to be injected into a thermal oxidation apparatus without the need for separate evaporation equipment. Furthermore, direct injection reduces residence time and minimizes the size of the required equipment.

[0008] Accordingly, the present invention may be characterized in at least one embodiment by providing a process for converting polyfluoroalkyl compounds and perfluoroalkyl compounds (PFAS) by oxidizing a feed containing PFAS in an oxidation zone to provide an oxidized effluent containing fluoride species; neutralizing the fluoride species with solid reactants in a mineralization reaction zone including a container containing solid reactants; and converting PFAS in the thermal oxidized effluent into fluorine salts using solid reactants in the mineralization reaction zone.

[0009] 90–99.9999% of the PFAS in the feedstock can be thermally oxidized in the thermal oxidation zone.

[0010] The solid reactants may be selected from the group consisting of bases comprising calcium, sodium, potassium, lithium, magnesium, aluminum, silicon, and combinations thereof.

[0011] Oxidation can be carried out at temperatures ranging from approximately 500°C to approximately 2,300°C.

[0012] Neutralization and conversion can be carried out in a container at a temperature between approximately ambient temperature and about 1,000°C.

[0013] Oxidation may be carried out at a first temperature, and neutralization and conversion may be carried out in a container at a second temperature at least 5% lower than the first temperature.

[0014] This process may further include cooling the thermal oxidation effluent in a thermal reduction zone before neutralization and conversion.

[0015] The supply may contain liquid PFAS.

[0016] In another embodiment, the present invention can be broadly characterized by providing a method for converting poly and perfluoroalkyl compounds (PFAS) by sending a feed containing PFAS to an oxidation zone, the oxidation zone comprising a container configured to oxidize the PFAS to fluoride species rides and provide an oxidation effluent; and sending the oxidation effluent to a reaction zone comprising a container having solid reactants, the solid reactants configured to neutralize fluoride species and convert any PFAS in the oxidation effluent into fluorinated salts.

[0017] The oxidation zone is configured to oxidize 90-99.9999% of the PFAS from the feedstock.

[0018] The solid reactants may be selected from the group consisting of bases comprising calcium, sodium, potassium, lithium, magnesium, aluminum, silicon, and combinations thereof.

[0019] The container in the oxidation zone can operate at temperatures ranging from approximately 500°C to approximately 2,300°C.

[0020] The vessel in the reaction zone can be operated at a temperature of approximately ambient temperature to about 1,000 °C.

[0021] The process can include sending the oxidized effluent to a cooling zone to reduce the temperature of the oxidized effluent before sending the oxidized effluent to the reaction zone.

[0022] The feed may contain liquid PFAS.

[0023] Another aspect of the present invention can generally be characterized by providing an apparatus for converting poly- and perfluoroalkyl substances (PFAS). The apparatus has a vessel and is configured to be operated at a first temperature to receive a feed containing PFAS and either oxidize the PFAS to fluoride species or provide an oxidized effluent, and a reaction zone having a vessel configured to be operated at a second temperature and having a solid reactant, the solid reactant being configured to neutralize fluoride species and convert PFAS in the oxidized effluent to fluorine salts. The second temperature is at least 5% lower than the first temperature.

[0024] The reaction zone may include a first reactor and a second reactor, and the second reactor may be operated at a third temperature, the third temperature being at least 5% lower than the second temperature.

[0025] The vessel of the oxidation zone may include a thermal oxidizer.

[0026] The solid reactant may be selected from the group consisting of bases of calcium, sodium, potassium, lithium, magnesium, aluminum, silicon, and combinations thereof.

[0027] The first temperature may be between about 500 °C and about 2,300 °C.

[0028] Further aspects, embodiments, and details of the present invention, all of which can be combined in any manner, are described in the following detailed description of the present invention.

Brief Description of the Drawings

[0029] One or more exemplary embodiments of the present invention will be described below in conjunction with each of the following drawings. [Figure 1] A schematic diagram of an apparatus according to one or more embodiments of the present application is shown.

Modes for Carrying Out the Invention

[0030] As described above, the present invention enables the removal and decomposition of PFAS. PFAS is oxidized in a thermal oxidation device, and then the residual PFAS can be decomposed in one or more mineralization reactors. Mineralization reduces the opportunity for the release of light fluorinated hydrocarbons or other components from the oxidation of PFAS. Further, the mineralization reactor neutralizes the fluoride species generated by oxidation.

[0031] As used herein, "PFAS" means poly and perfluoroalkyl substances, including fluorinated resins, that contain at least one fully fluorinated methyl or methylene carbon atom. Commonly manufactured, used, or discovered compounds include perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorobutane sulfonic acid (PFBS), perfluoropentane sulfonic acid (PFPS), perfluorohexane sulfonic acid (PFHxS), perfluoroheptane sulfonic acid (PFHpS), perfluorononane sulfonic acid (PFNS), or perfluorodecane sulfonic acid (PFDS), hexafluoropropylene oxide dimer acid (HFPO-DA). This list is not intended to be exhaustive and is merely illustrative. Additional PFAS compounds can be found, for example, in the definitions provided by the EPA. Further, it should be understood that "PFAS" also refers to intermediate compounds generated during the conversion of the original PFAS compounds.

[0032] As used herein, the term “flow” may include a variety of hydrocarbon molecules, such as linear, branched, or cyclic alkanes, alkenes, alkadienes, and alkynes, and optionally other substances, such as gases (e.g., hydrogen) or impurities (e.g., heavy metals, sulfur compounds, nitrogen compounds). Aromatic and non-aromatic hydrocarbons may also be included in the flow.

[0033] As used herein, the term “substantially” can mean an amount of at least 90%, preferably 95%, and optimally 99% by weight of the compound or class of compounds in the flow.

[0034] As shown in the diagram, the process flow line in the diagram can be referred to as a line, pipe, feed, outflow, product, or flow, all of the same meaning.

[0035] As used herein, the term “zone” may refer to an area containing one or more pieces of equipment and / or one or more subzones. Examples of equipment include one or more reactors or reaction vessels, heaters, exchangers, pipes, pumps, compressors, and controllers. In addition, equipment such as reactors, dryers, or vessels may further comprise one or more zones or subzones.

[0036] In consideration of these general principles, one or more embodiments of the present invention are described with the understanding that the following description is not intended to be limiting.

[0037] Referring to the figure, an apparatus 10 for converting poly and perfluoroalkyl materials (PFAS) is shown. Apparatus 10 accepts a feed stream 12 containing PFAS. In various embodiments, the feed stream 12 is a liquid feed stream containing PFAS in either liquid phase or dissolved solid phase. The feed stream 12 is intended to contain about 0.01% by weight of PFAS or about 10% by weight of PFAS. However, these amounts are illustrative only and not intended to be limiting. Furthermore, "about" means including + / - 10% of the stated amount.

[0038] The feed stream 12 is sent to an oxidation zone 14 which includes at least one reaction vessel 16. In the oxidation zone 14, the PFAS is oxidized to one or more fluoride species, such as anionic fluoride species, among other components. In a preferred embodiment, the oxidation zone 14 includes a thermal oxidation zone 18, in which at least a portion of the reaction vessel 16 includes a thermal oxidation device 20. Therefore, the oxidation effluent may also include combustion products.

[0039] As is well known, the thermal oxidation apparatus 20 includes one or more burners 22 that receive a fuel gas stream 24 and a combustion air stream 26 that react within the thermal oxidation zone 18 to produce a flame. The temperature intended for the thermal oxidation zone 18 is a temperature sufficient to oxidize the PFAS and may be about 500°C to about 2,300°C. Furthermore, the intended residence time may be less than about 30 seconds, or less than about 15 seconds, or less than about 10 seconds, or about 0.5 to about 3 seconds. Hereinafter, these are merely intended or exemplary values ​​and are not intended to be limiting.

[0040] The feed stream 12 can be injected into the thermal oxidation zone 18. One or more injection nozzles 28 can be provided in the reaction vessel 16 to inject the feed stream 12 into the thermal oxidation zone 18. The feed stream 12 can be sprayed before entering the reaction vessel 16. For example, the feed stream 12 may be sprayed with a spray fluid 30, such as air, and then the spray fluid and liquid PFAS (to be sprayed) may be injected into the thermal oxidation zone 18. Alternatively, the feed stream 12 may be sprayed with a mechanical sprayer, and therefore a separate spray fluid 30 may not be required to spray the feed stream 12.

[0041] According to the process of the present invention, at least 90% by weight, or 90-99.999% by weight, or 90-99.9999% by weight of the PFAS from the supply stream 12 is converted to fluoride species in the oxidation zone 14. In some embodiments, 100% by weight of the PFAS is converted to fluoride species in the oxidation zone 14.

[0042] To increase the decomposition of PFAS and reduce the reactivity of fluoride species, the oxidation zone effluent 32 is sent to the reaction zone 40. However, prior to the reaction zone 40, the oxidation zone effluent 32 may be cooled in the thermal reduction zone 34 or the cooling zone, resulting in a temperature reduction of at least 5% of the oxidation zone effluent 32.

[0043] The heat reduction zone 34 may include a heat exchange zone having a heat exchanger configured to transfer heat from the oxidation zone effluent 32 to the heat exchange fluid. The heat exchanger may be located inside or outside the reaction vessel 16.

[0044] Additionally, or alternatively, the thermal reduction zone 34 may include a quenching zone 36, which may be part of the reaction vessel 16 within the oxidation zone 14. The quenching zone 36 receives a quenching fluid 38, which can be injected into the quenching zone. The quenching fluid 38 may be water, air, or a combination thereof.

[0045] In some embodiments, sensors (not shown) or other monitoring devices can be used to measure the temperature of the oxidation zone effluent 32 at various points (i.e., upstream and / or downstream of the heat reduction zone 34). The obtained or measured temperatures may be compared to a predetermined temperature or other setpoint, and the flow of the cooling fluid (i.e., heat exchange fluid and / or quenching fluid 38) may be adjusted in accordance with the comparison to increase or decrease the temperature of the oxidation zone effluent 32.

[0046] Whether or not thermal reduction is performed, the effluent 32 from the oxidation zone is sent to the reaction zone 40 to reduce the reactivity of the fluoride species and increase the decomposition of PFAS. On the other hand, oxidation may be carried out at a first temperature, and neutralization and conversion may be carried out at a second temperature at least 5% lower than the first temperature.

[0047] The reaction zone 40 may include one or more mineralization reactors 42. If one or more mineralization reactors 42 are used, the reactors 42 may be arranged in series, in parallel, or in other configurations.

[0048] Each mineralization reactor 42 is configured to operate at a temperature between ambient temperature and approximately 1,000°C. Furthermore, different reactors 42 are intended to have different operating temperatures. For example, the first mineralization reactor 42 may have an operating temperature of approximately 300°C to approximately 1,000°C, while the second mineralization reactor 42, which receives the effluent from the first mineralization reactor, may have an operating temperature of approximately ambient temperature to approximately 1,000°C.

[0049] Mineralization minimizes emissions of light fluorinated hydrocarbons (which have a much higher global warming potential than carbon dioxide). The mineralization reactor 42 contains solid reactants configured to neutralize fluoride species and convert any PFAS in the oxidative effluent into fluorinated salts (as well as carbon dioxide, water, and other compounds). The solid reactants may be bases of calcium, sodium, potassium, lithium, magnesium, aluminum, silicon, and combinations thereof. "Base" means including oxides, hydroxides, carbonates, phosphates, and silicates. Therefore, the solid reactants may be salts of calcium, sodium, potassium, lithium, magnesium, or combinations thereof, or aluminum oxide, or both. For example, the solid reactants may be calcium hydroxide, calcium oxide, calcium carbonate, or combinations thereof.

[0050] The oxidation zone effluent 32 may remain in the mineralization reactor 42 and / or in the presence of solid reactants for 0.5 seconds to 10 minutes.

[0051] The effluent 44 from the reaction zone 40 may be treated in a treatment zone (not shown) which may include wet scrubbers, dry scrubbers, protective floors, catalytic reaction zones, or any combination thereof, before being released into the atmosphere.

[0052] Any of the lines, conduits, units, devices, containers, surrounding environments, zones, or similar entities described above may comprise one or more monitoring components, including sensors, measuring devices, data acquisition devices, or data transmission devices. Signals, process, or state measurements and data from the monitoring components can be used to monitor conditions within, around, and on process equipment. Signals, measurements, and / or data generated or recorded by the monitoring components may be collected, processed, and / or transmitted via one or more networks or connections, which may be private or public, general or specific, direct or indirect, wired or wireless, encrypted or unencrypted, and / or a combination thereof. This specification is not intended to limit us in this respect.

[0053] Signals, measurements, and / or data generated or recorded by the monitoring components may be transmitted to one or more computing devices or systems. A computing device or system may include at least one processor and memory for storing computer-readable instructions that, when executed by at least one processor, cause one or more computing devices to perform a process that may include one or more steps.

[0054] For example, one or more computing devices may be configured to receive data from one or more monitoring components relating to at least one component of equipment associated with a process. One or more computing devices or systems may be configured to analyze the data. Based on the analysis of the data, one or more computing devices or systems may be configured to determine one or more recommended adjustments to one or more parameters of one or more processes described herein. One or more computing devices or systems may be configured to transmit encrypted or unencrypted data containing one or more recommended adjustments to one or more parameters of one or more processes described herein.

[0055] experiment thermal oxidation Modeling the thermal oxidation zone begins with the known properties of the fuel, atmosphere, and waste (PFAS + others, where applicable). Using industry-known values, including but not limited to latent heat of vaporization, heat capacity, adiabatic flame temperature, and the chemical composition of these flows (where applicable), the model can begin calculating the estimated flame temperature within the oxidation zone. The operating temperature of the bulk oxidation zone is then modeled using the target excess oxygen value. Since the size and shape of the oxidation zone container can be freely adjusted by the designer, calculations can be made to determine the bulk residence time of the oxidation zone based on this specific shape, vapor flow rate, and temperature. By combining years of operational data (temperature profiles, fuel flow rates, chimney exhaust samples, etc.) collected from units designed to oxidize halogen-containing organic waste with the aforementioned calculation data, a sufficient oxidation zone model can be created to target the desired oxidation and removal efficiency.

[0056] In the thermal oxidation zone modeling, a PFAS-containing wastewater stream consisting of 0.5 wt% PFAS and 99.5 wt% water was oxidized in a thermal oxidation modeling program at 1,343.3°C and a minimum residence time of 2 seconds. Pure methane was used as the fuel source for oxidation, and ambient air was used as the oxygen source. The theoretical model results showed a conversion rate of over 99.9999% of PFAS waste to HF.

[0057] HF neutralization The neutralization of HF by mineralization using a Ca-based adsorbent was modeled using a shrinking core model. This model is used to help determine the required number of mineralization reactors, as well as the size of the reactor mineralization reactor or reactor. The shrinking core model is affected by several material parameters, including particle porosity, pore size, particle diameter, and HF diffusivity, as well as reactor conditions (temperature, HF concentration). Furthermore, the equilibrium concentration of HF under mineralization reactor conditions in the presence of other molecules (water, CO2) is key to determining the potential need for multiple reactors in series.

[0058] Evaporates from a modeled thermal oxidation reactor containing both HF and PFAS materials were simulated in Unisim and cooled from the thermal oxidation reactor efflorescence temperature to 550°C using a quenching fluid (either air or water). This cooled flow provided inlet conditions to a mineralization / neutralization reactor model, including flow rate, temperature, and pressure, as well as concentrations of HF, CO2, and water. Reactor inlet conditions for air and water quenching are outlined in Table 1 below.

[0059] [Table 1]

[0060] These reactor inlet conditions are used to determine the effective diffusion rate (48 cm²). 2 The estimated particle diameter (0.21 cm) and the output of the model were input into the shrinking core neutralization model. The model output predicted the mineralization zone length. This, combined with the operating time and pressure drop requirements, was used to determine the size of the reactor diameter and tangential length. The equilibrium HF slip was also calculated based on the reactor conditions shown in Table 2 below.

[0061] [Table 2]

[0062] In the cases of rapid cooling with air and water described above, the equilibrium HF slip is 3 ppm and 9 ppm, respectively. By performing an additional cooling step and a polishing mineralization reactor following the primary mineralization reactor, the equilibrium HF slip can be reduced to meet environmental regulations. For example, cooling to 300°C with rapid cooling with air and water yields HF slips of 0.1 ppm and 0.3 ppm, respectively.

[0063] PFAS and calcium bases PFOA (0.15 g) was dissolved in water (15 g), and UOP zeolite (0.98 g) was added. The zeolite was prepared according to the method described in U.S. Patent No. 10632454. The mixture was stirred at room temperature for 1 day. The solid was separated from the liquid by centrifugation. The zeolite was mixed with water and centrifuged to wash away the unadsorbed PFAS. The PFOA-supported zeolite was dried at 80°C in a rotary evaporator. PFOA-supported zeolite (1.0 g) was mixed with calcium oxide (1.42 g) and ground using a mortar and pestle. The solid mixture was then slowly poured into a glass reactor and heated in a furnace at 525°C for 20 minutes. After cooling, the solid was analyzed by XRD. XRD showed the formation of calcium fluoride. Similar results are expected when PFAS is introduced into a calcium base.

[0064] Specific Embodiments The following will be explained in conjunction with specific embodiments, but it should be understood that this explanation is intended to illustrate the scope of the preceding explanation and the attached claims, and is not intended to limit them.

[0065] A first embodiment of the present invention is a process for converting poly and perfluoroalkyl materials (PFAS), comprising: oxidizing a feed containing PFAS in an oxidation zone to provide an oxidized effluent containing fluoride species; neutralizing the fluoride species with a solid reactant in a mineralization reaction zone including a container having a solid reactant; and converting any PFAS in the thermal oxidized effluent to a fluorine salt with a solid reactant in the mineralization reaction zone. Embodiments of the present invention are any or all of the embodiments described in this paragraph up to the first embodiment of this paragraph, wherein 90 to 99.9999% of the PFAS in the feed is thermally oxidized in the thermal oxidation zone. Embodiments of the present invention are any or all of the embodiments described in this paragraph up to the first embodiment of this paragraph, wherein the solid reactant is selected from the group consisting of bases of calcium, sodium, potassium, lithium, magnesium, aluminum, silicon, and combinations thereof. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the first embodiment of this paragraph, where oxidation is carried out at a temperature of about 500°C to about 2,300°C. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the first embodiment of this paragraph, where neutralization and conversion are carried out in a vessel at a temperature between approximately room temperature and about 1,000°C. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the first embodiment of this paragraph, where oxidation is carried out at a first temperature, and neutralization and conversion are carried out in a vessel at a second temperature at least 5% lower than the first temperature. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the first embodiment of this paragraph, further comprising cooling the thermal oxidation effluent in a thermal reduction zone before neutralization and conversion. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the first embodiment of this paragraph, where the feed comprises liquid PFAS.

[0066] A second embodiment of the present invention is a process for converting poly and perfluoroalkyl materials (PFAS), comprising: sending a feed containing PFAS to an oxidation zone, the oxidation zone comprising a container configured to oxidize the PFAS to fluoride species and provide an oxidation effluent; and sending the oxidation effluent to a reaction zone comprising a container having a solid reactant, the solid reactant configured to neutralize the fluoride species and convert any PFAS in the oxidation effluent into a fluorine salt. Embodiments of the present invention are any or all of the embodiments described in this paragraph up to the second embodiment of this paragraph, wherein the oxidation zone is configured to oxidize 90 to 99.9999% of the PFAS from the feed. Embodiments of the present invention are any or all of the embodiments described in this paragraph up to the second embodiment of this paragraph, wherein the solid reactant is selected from the group consisting of bases of calcium, sodium, potassium, lithium, magnesium, aluminum, silicon, and combinations thereof. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the second embodiment of this paragraph, wherein the vessel in the oxidation zone operates at a temperature of approximately 500°C to approximately 2,300°C. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the second embodiment of this paragraph, wherein the vessel in the reaction zone operates at a temperature between approximately room temperature and approximately 1,000°C. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the second embodiment of this paragraph, further comprising sending the oxidation effluent to a cooling zone to reduce the temperature of the oxidation effluent before sending it to the reaction zone. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the second embodiment of this paragraph, wherein the feed comprises liquid PFAS.

[0067] A third embodiment of the present invention is an apparatus for converting poly and perfluoroalkyl materials (PFAS), the apparatus comprising an oxidation zone comprising a container and configured to operate at a first temperature to receive a feed containing PFAS and to oxidize the PFAS to fluoride species or to provide an oxidative effluent, and a reaction zone comprising a container having a solid reactant configured to operate at a second temperature, the solid reactant configured to neutralize the fluoride species and convert any PFAS in the oxidative effluent to carbon dioxide, water, and fluoride salts, the second temperature being at least 5% lower than the first temperature. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the third embodiment of this paragraph, the reaction zone comprising a first reactor and a second reactor, the second reactor operating at a third temperature, the third temperature being at least 5% lower than the second temperature. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the third embodiment of this paragraph, the container in the oxidation zone comprising a thermal oxidation device. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the third embodiment of this paragraph, wherein the solid reactants are selected from the group consisting of bases comprising calcium, sodium, potassium, lithium, magnesium, aluminum, silicon, and combinations thereof. Embodiments of the present invention are one or all of the embodiments described in this paragraph up to the third embodiment of this paragraph, wherein the first temperature is about 500°C to about 2,300°C.

[0068] Without further detail, it is expected that those skilled in the art will be able to utilize the invention to the fullest extent without departing from the spirit and scope of the invention, and will readily identify its essential characteristics, and will be able to make various changes and modifications to the invention to suit various uses and conditions. Accordingly, the prior preferred specific embodiments should be interpreted as merely illustrative and not to limit the remainder of this disclosure in any way, but are intended to cover various modifications and equivalent configurations that fall within the scope of the appended claims.

[0069] In the above, all temperatures are given in degrees Celsius, and all parts and percentages are based on weight unless otherwise indicated.

[0070] Without further detail, it is expected that those skilled in the art will be able to utilize the invention to the fullest extent without departing from the spirit and scope of the invention, and will readily confirm its essential characteristics, and will be able to make various changes and modifications to the invention to suit various uses and conditions. Accordingly, the prior preferred specific embodiments should be interpreted as merely illustrative and not to limit the remainder of this disclosure in any way, but are intended to cover various modifications and equivalent configurations that fall within the scope of the appended claims. All temperatures above are given in degrees Celsius, and all parts and percentages are by weight unless otherwise indicated.

[0071] It should be recognized and understood by those skilled in the art that various other components, such as valves, pumps, filters, and coolers, are not shown in the drawings because their details are well within the scope of knowledge of those skilled in the art, and their description is not essential for the practice or understanding of embodiments of the present invention.

Claims

1. A process for converting poly and perfluoroalkyl substances (PFAS), wherein the process is: In the oxidation zone (14), the feed (12) containing PFAS is oxidized to provide an oxidized effluent (32) containing fluoride species. In a mineralization reaction zone (40) including a container (42) containing solid reactants, the fluoride species is neutralized using the solid reactants, A process comprising converting any PFAS in the oxidation effluent (32) into a fluorine salt using the solid reactant in the mineralization reaction zone (40).

2. The process according to claim 1, wherein 90 to 99.9999% of the PFAS in the feed is thermally oxidized in the oxidation zone (14).

3. The process according to claim 1, wherein the solid reactant is selected from the group consisting of calcium, sodium, potassium, lithium, magnesium, aluminum, silicon, and bases of combinations thereof.

4. The process according to claim 1, wherein the oxidation is carried out at a temperature of approximately 500°C to 2,300°C.

5. The process according to claim 1, wherein the neutralization and conversion are carried out in a container (42) at a temperature of approximately ambient temperature to about 1,000°C.

6. The process according to any one of claims 1 to 5, wherein the oxidation is carried out at a first temperature, and the neutralization and conversion are carried out in the container (42) at a second temperature at least 5% lower than the first temperature.

7. The process according to any one of claims 1 to 5, further comprising cooling the oxidized effluent (32) in a thermal reduction zone (34) before the neutralization and conversion.

8. The process according to claim 1, wherein the feed (12) comprises liquid PFAS.

9. An apparatus for converting poly and perfluoroalkyl substances (PFAS), wherein the apparatus is An oxidation zone (14) comprising a container (16), which is configured to receive a feed (12) containing PFAS and to operate at a first temperature to oxidize the PFAS to a fluoride species or to provide an oxidation effluent (34), The reaction zone (40) includes a container (42) having a solid reactant, configured to operate at a second temperature, wherein the solid reactant is configured to neutralize the fluoride species and convert any PFAS in the oxidative effluent (34) into carbon dioxide, water, and fluoride salts, The apparatus wherein the second temperature is at least 5% lower than the first temperature.

10. The apparatus according to claim 17, wherein the container (16) of the oxidation zone (14) includes a thermal oxidation device (20).

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