SE547331C2

SE547331C2 - Decontamination of pfas

Info

Publication number: SE547331C2
Application number: SE2251594A
Authority: SE
Inventors: Ragnar Krefting
Original assignee: Lifeclean Int Ab
Priority date: 2022-12-29
Filing date: 2022-12-29
Publication date: 2025-07-01
Also published as: SE2251594A1; SE547328C2; SE2350754A1

Abstract

[0088] The present invention relates generally to a method for removing, decontaminating and/or decomposing per- and polyfluoroalkyl substances (PFAS) from a substrate. The present document also discloses use of an aqueous composition and a defoamerfor removing, decontaminating and/or decomposing per- and polyfluoroalkyl substances (PFAS) from a substrate, said aqueous composition comprising chlorine dioxide and a surfactant system.

Claims

CLÅEMS

1. A method for removing, decontaminating and/or decomposing per- and polyfluoroalkyl substances (PFAS) from a substrate, wherein said method comprises applying to said substrate an aqueous composition having a pH of from about 1 to about 4, said aqueous composition comprising from about 100 to about 2000 ppm dissolved chlorine dioxide and a surfactant system, -\..-.__.\~ .w- »;--.-.~+~..-\-,~.v\ .«\_.~..~\_~~ :.~\ .-~v ~ w v. ,~ vv. s s. t. s v _ g §>..:~^:~<;~>š~~wherein said surfactant system comprises or consists of at least one hydrocarbon ionic surfactant stable for oxidation at said pH, ...M på _. _»\ _.\« _¿\ .\ _ v? \.._ ,.\~ §.\. _. . ;.\ ...v g... ,.\~ _¿\\\_,\\ _.\ ...v-_ “_ v. v ,\ _.\ ,.\v\ v ,- ..__ ^~ v ,.\ v _.\ . vd .\ . . \ \ ,.v._,\_ , v. ,.\ v.. .v v. \ .v '\.-= :ss f.\\.~?\:..~.= :.«:.\3\.= :..-\= k: :fn f; \.::.“.~:\š .\- _.\ s. _ »VM-w Nav-M K s . i _ 4 f 3 U k? \_-'\š Lä så \=\$I

2. The method according to claim 1, wherein said at least one hydrocarbon ionic surfactant in said surfactant system is cationic at a pH in the range of from about 1 to about

3. The method according to any one of the claims 1 and 2, wherein said at least one hydrocarbon ionic surfactant in said surfactant system comprises or consists of at least one amine oxide having alkyl groups with 6 to 18 carbon atoms.

4. The method according to any one of the previous claims, wherein said surfactant system comprises or consists of at least two hydrocarbon ionic surfactants stable for oxidation at said pH, wherein said at least two hydrocarbon ionic surfactants have a difference in hydrocarbon chain length of at least four carbon atoms.

5. The method according to claim 4, wherein said at least two hydrocarbon ionic surfactants in said surfactant system comprise or consist of a C-8 amine oxide and a C-12 amine oxide.

6. The method according to any one of the claims 4 and 5, wherein said at least two hydrocarbon ionic surfactants in said surfactant system comprise or consist of octyldimethylamine oxide and lauryldimethylamine oxide.

7. The method according to any one of the previous claims, wherein said at least one hydrocarbon ionic surfactant in said surfactant system is present in an amount of from about 0.01 % (v/v) to about 2% (v/v), based on the total volume of said aqueous composition.

8. The method according to any one of the previous claims, wherein said at least one hydrocarbon ionic surfactant in said surfactant system is present in an amount of about 0.2 % (v/v), based on the total volume of said aqueous composition, and said aqueous composition comprises essentially equal amounts of octyldimethylamine oxide and lauryldimethylamine oxide.

9. The method according to any one of the previous claims, wherein said substrate is one or more of a surface, a solution and/or a mass.

10.The method according to any one of the previous claims, wherein said substrate is a surface, said method comprising the steps of: a) applying said aqueous composition to said surface, b) removing said aqueous composition from said surface, c) optionally repeating step a) and/or step b) at least one time.

11.The method according to claim 10, wherein said aqueous composition applied in step a) is left on said surface for at least 10 minutes, such as for at least 30 minutes, such as for at least 40 minutes, before said aqueous composition is removed from said surface in step b).

12.The method according to any one of the claims 10 and 11, wherein step b) comprises rinsing said surface with water.

13.The method according to any one of the claims 10-12, wherein said surface is comprised in a firefighting equipment, such as in a fire truck tank, in a storage container for fire extinguishing agents or in a personal safety equipment, such as protective Clothing, protective glasses and/or helmets.

14.The method according to any one of the claims 1-9, wherein said substrate is one or more of a water solution, groundwater, soil, concrete and/or sediments.

15.The method according to any one of the previous claims, wherein at least 99%, such as at least 995%, such as at least 99.9% of the per- and polyfluoroalkyl substances (PFAS) present in said substrate are removed, decontaminated and/or decomposed from said substrate.

16. Use of an aqueous composition and a defoamer for removing, decontaminating and/or decomposing per- and polyfluoroalkyl substances (PFAS) from a substrate, said composition having a pH of from about 1 to about 4, said aqueous composition comprising from about 100 to about 2000 ppm dissolved chlorine dioxide and a surfactant system, wherein said surfactant system comprises or consists of at least one hydrocarbon ionic surfactant stable for oxidation at said pH.

17.The use according to claim 16, wherein said substrate is one or more of a surface, a solution and/or a mass.