Per- and polyfluoroalkyl substances (PFAS) are destroyed by oxidation in supercritical conditions. PFAS in water can be concentrated and prepared for destruction in a pretreatment phase. Following annihilation of the PFAS in supercritical conditions to levels below 5 parts per trillion (ppt), the water effluent can be used to recover heat, returned to sub-critical conditions, and then released back into the environment.

A calcium fluoride precipitation inhibitor is added to waste water containing sulfuric acid, fluorine (fluoride ions and hydrogen fluoride) and heavy metal ions to generate pretreated water. A calcium compound is added to the pretreated water to generate a first insolubilized product at a pH of less than 5, followed by solid-liquid separation. A calcium compound is added to a first separated water after the solid-liquid separation to generate a second insolubilized product at a pH of 3 to 7 (provided that the pH is a pH higher than in the first reaction step), followed by solid-liquid separation. An alkali is added to a second separated water after the solid-liquid separation to give a pH of 8 or more, thereby generating a third insolubilized product, followed by solid-liquid separation.

Disclosed are methods, apparatuses and systems for the remediation of contaminated soils, groundwater, water, and/or waste using a combination of reagents. The disclosed methods may be used to treat various recalcitrant halogenated substances, such as perfluoroalkyls and polyfluoroalkyls. Particular combinations of reagents that may be used in the disclosed methods include but are not limited to: (1) persulfate, oxygen and ozone; (2) persulfate, salt, oxygen and ozone; (3) persulfate, phosphate, and/or oxygen; (4) persulfate, phosphate, oxygen and ozone; (5) persulfate, phosphate, salt and oxygen (6) persulfate, phosphate, salt, oxygen and ozone; (7) oxygen and salt; and (8) air and salt. The disclosed methods may enhance destruction of organic contaminants in the liquid phase and may also control the rate of aerosol or foam formation relative to the rate of chemical oxidation and/or reduction/transfer.

The invention discloses a modularized fluoride-containing wastewater treating apparatus, comprising: a fluoride removal module, which is used to remove most of the fluoride in the high-concentration fluoride-containing wastewater transported to the fluoride removal module by cryolite crystallizing to generate a mixture of unextracted cryolite crystals and a low-concentration fluoride-containing wastewater; and an extracting module connected with the fluoride removal module, which is used to extract the mixture of unextracted cryolite crystals and a low-concentration fluoride-containing wastewater to separate cryolite crystals with a water content less than 60% or cryolite crystals with a water content less than 10% and a purity of 95%, a wastewater that meets the discharge standard and a condensed fluoride-containing liquid, wherein the condensed fluoride-containing liquid will be recycled to the fluoride removal module.

Disclosed are methods, apparatuses and systems for the remediation of contaminated soils, groundwater, water, and/or waste using a combination of reagents. The disclosed methods may be used to treat various recalcitrant halogenated substances, such as perfluoroalkyls and polyfluoroalkyls. Particular combinations of reagents that may be used in the disclosed methods include but are not limited to: (1) persulfate, oxygen and ozone; (2) persulfate, salt, oxygen and ozone; (3) persulfate, phosphate, and/or oxygen; (4) persulfate, phosphate, oxygen and ozone; (5) persulfate, phosphate, salt and oxygen (6) persulfate, phosphate, salt, oxygen and ozone; (7) oxygen and salt; and (8) air and salt. The disclosed methods may enhance destruction of organic contaminants in the liquid phase and may also control the rate of aerosol or foam formation relative to the rate of chemical oxidation and/or reduction/transfer.

A method may be provided for removing fluorinated organic compounds from contaminated fluids by means of a kit that comprises a first and a second adsorbent component, or only by means of the first adsorbent component alone. The second adsorbent component is a solid adsorbent; the first adsorbent component is a chemical compound that contains a lipophilic group and a hydrophilic group, or contains such a compound in dissolved form, wherein the hydrophilic group contains at least one cationic group and wherein the lipophilic group is selected from alkyl groups that comprise at least one octylene unit, from aryl groups, and from aralkyl groups. The contaminated fluid may be brought in contact with the first adsorbent component, and optionally the fluid is also brought in contact with the second adsorbent component. The adsorbent component(s) may be removed from the fluid together with the adsorbed fluorinated organic compounds.

In certain embodiments, the present invention is directed to a process for decontaminating water to remove per- and polyfluoroalkyl substances (PFAS), the process comprising passing contaminated water through a filter comprising at least one filtering element, wherein the filtering element comprises organic fibers; wherein the decontaminated water has a PFAS level of less than 70 ppt.

Disclosed are methods, apparatuses and systems for the remediation of contaminated soils, groundwater, water, and/or waste using a combination of reagents. The disclosed methods may be used to treat various recalcitrant halogenated substances, such as perfluoroalkyls and polyfluoroalkyls. Particular combinations of reagents that may be used in the disclosed methods include but are not limited to: (1) persulfate, oxygen and ozone; (2) persulfate, salt, oxygen and ozone; (3) persulfate, phosphate, and/or oxygen; (4) persulfate, phosphate, oxygen and ozone; (5) persulfate, phosphate, salt and oxygen (6) persulfate, phosphate, salt, oxygen and ozone; (7) oxygen and salt; and (8) air and salt. The disclosed methods may enhance destruction of organic contaminants in the liquid phase and may also control the rate of aerosol or foam formation relative to the rate of chemical oxidation and/or reduction/transfer.

The present invention describes a method of capturing a fluorinated carbon compound located within a liquid, the method comprising contacting the fluorinated carbon compound with a block copolymer having a backbone comprising a hydrophilic block and a fluoropolyether block, wherein the fluorinated carbon compound binds to and is captured by the block copolymer.

Per- and polyfluoroalkyl substances (PFAS) are destroyed by oxidation in supercritical conditions. PFAS in water can be concentrated and prepared for destruction in a pretreatment phase. Following annihilation of the PFAS in supercritical conditions to levels below 5 parts per trillion (ppt), the water effluent can be used to recover heat, returned to sub-critical conditions, and then released back into the environment.