Methods and systems for treating a waste substance containing perfluoro- and polyfluoroalkyl substances (PFAS) and mineralizing the PFAS, at least partially. The method includes combining the PFAS with a first amendment in a reactor to create a combination, heating and pressurizing the combination to hydrothermal conditions, and holding the combination at hydrothermal conditions for a holding time sufficient to at least partially mineralize the PFAS to create a treated combination.

Methods and systems for treating a waste substance containing perfluoro- and polyfluoroalkyl substances (PFAS) and mineralizing the PFAS, at least partially. The method includes combining the PFAS with a first amendment in a reactor to create a combination, heating and pressurizing the combination to hydrothermal conditions, and holding the combination at hydrothermal conditions for a holding time sufficient to at least partially mineralize the PFAS to create a treated combination.

A method for destructing and valorizing an asbestos waste including the steps of: determining the asbestos mineralogical group contained in the waste, performing a treatment on the waste which includes of: an acid treatment when the waste comprises only a chrysotile, a base treatment when the waste comprises only an amphibole, the acid treatment followed by the base treatment when the asbestos waste includes a mixture of a chrysotile and an amphibole, and valorizing at least one of the products obtained on completion of the performing of the treatment. An embodiment also concerns a treatment of a chrysotile waste through an acid treatment followed by a thermal treatment.

A method for destructing and valorizing an asbestos waste including the steps of: determining the asbestos mineralogical group contained in the waste, performing a treatment on the waste which includes of: an acid treatment when the waste comprises only a chrysotile, a base treatment when the waste comprises only an amphibole, the acid treatment followed by the base treatment when the asbestos waste includes a mixture of a chrysotile and an amphibole, and valorizing at least one of the products obtained on completion of the performing of the treatment. An embodiment also concerns a treatment of a chrysotile waste through an acid treatment followed by a thermal treatment.

A method comprising a) mixing and dissolving the solid hazardous heavy metal-containing composition with an acid solution; b) precipitating the heavy metal from the hazardous heavy metal acid composition; c) precipitating the heavy metal from the hazardous heavy metal acid composition with a heavy metal-precipitation agent; and d) separating out the heavy metal precipitate from the aqueous supernatant, whereby the heavy metal-precipitation agent comprises a diorgano-dithiophosphinic acid or the alkali metal or ammonia salts thereof.

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A method comprising a) mixing and dissolving the solid hazardous heavy metal-containing composition with an acid solution; b) precipitating the heavy metal from the hazardous heavy metal acid composition; c) precipitating the heavy metal from the hazardous heavy metal acid composition with a heavy metal-precipitation agent; and d) separating out the heavy metal precipitate from the aqueous supernatant, whereby the heavy metal-precipitation agent comprises a diorgano-dithiophosphinic acid or the alkali metal or ammonia salts thereof.

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Disclosed herein is a decontaminant aqueous solution for decontaminating diisocyanate drum, including 20-97 wt % of at least one alcohol or derivative thereof, based on the total weight of decontaminant aqueous solution, and an alkaline source in an amount effective to provide the solution a pH of at least 8. Further disclosed herein is a method for decontaminating diisocyanate residues in an emptied drum with the decontaminant aqueous solution.

Disclosed herein is a decontaminant aqueous solution for decontaminating diisocyanate drum, including 20-97 wt % of at least one alcohol or derivative thereof, based on the total weight of decontaminant aqueous solution, and an alkaline source in an amount effective to provide the solution a pH of at least 8. Further disclosed herein is a method for decontaminating diisocyanate residues in an emptied drum with the decontaminant aqueous solution.

A reagent set includes an oxidant, acid, and adsorbent, which is used in a method for reducing the leachability and release of PFAS, mercury, and other contaminants from soils, sediments, and other solid materials or waste when treated materials are exposed to acid rain, snow melt, runoff, landfill leachate, etc. The reagents are mixed with a quantity of contaminated material and water is added as needed in order to reduce the leachability of the contaminants from the treated host material, where the admixture end-product suitably removes contaminants from fluids that contact and/or otherwise permeate and/or pass through and/or around the treated admixture. The reagent set and method of use offer environmental professionals long-term, economically viable waste management solutions for removing contaminants from contamination source areas, spill and manufacturing release sites, impacted media, and landfills, as well as from the fluids that contact reagent-treated material.

A reagent set includes an oxidant, acid, and adsorbent, which is used in a method for reducing the leachability and release of PFAS, mercury, and other contaminants from soils, sediments, and other solid materials or waste when treated materials are exposed to acid rain, snow melt, runoff, landfill leachate, etc. The reagents are mixed with a quantity of contaminated material and water is added as needed in order to reduce the leachability of the contaminants from the treated host material, where the admixture end-product suitably removes contaminants from fluids that contact and/or otherwise permeate and/or pass through and/or around the treated admixture. The reagent set and method of use offer environmental professionals long-term, economically viable waste management solutions for removing contaminants from contamination source areas, spill and manufacturing release sites, impacted media, and landfills, as well as from the fluids that contact reagent-treated material.