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Perfluorosulfonic acids (PFSAs) are chemical compounds of the formula C n F (2n+1) SO 3 H and thus belong to the family of perfluorinated and polyfluorinated alkyl compounds (PFASs). The simplest example of a perfluorosulfonic acid is the trifluoromethanesulfonic acid .
The process does not work on perfluorosulfonic acids such as PFOS. [235] A 2022 study published in Chemical Science shows breakdown of C-F bonds and their mineralization as YF 3 or YF 6 clusters. [236] Another study in the Journal of the American Chemical Society described the PFASs breakdown using metal-organic frameworks (MOFs). [237]
Perfluorobutanesulfonic acid (PFBS) is a PFAS chemical compound having a four-carbon fluorocarbon chain and a sulfonic acid functional group. It is stable and unreactive because of the strength of carbon–fluorine bonds. It can occur in the form of a colorless liquid or a corrosive solid. [1]
In both muscle and liver samples, the highest level of PFAS chemical was PFOS, at 82.6 parts per billion (ppb) in a muscle sample and 2,970 ppb in a liver sample. [ 112 ] [ 113 ] 14 September 2021 EPA announced plans to revise effluent guidelines for businesses that conduct chromium electroplating operations and discharge PFAS in their wastewater.
The PTFE backbone interlaced with the ionic sulfonate groups gives Nafion a high chemical stability temperature (e.g. 190 °C) but a softening point in the range of 85-100 °C give it a moderate operating temperature, e.g. up to 100 °C, with additional challenges in all applications due to the loss of water above 100 °C.
Trifluoroacetic acid is a widely employed acid, used for example in the synthesis of peptides.Its esters are useful in analytical chemistry. Longer-chain perfluoroalkyl carboxylic acids, e.g. with five to nine carbons, are useful fluorosurfactants and emulsifiers used in the production of polytetrafluoroethylene (Teflon) and related fluoropolymers.
Simply Orange Juice is accused of deceiving health-conscious customers into believing one of its juices is “all natural” as labeled — but it’s not, a class-action lawsuit says.
Each type of perfluoropolyether is synthesized differently: PFPE-K is obtained from HFPO by anionic polymerization.For PFPE-Y and PFBE-Z, photooxidation of hexafluoropropylene and tetrafluoroethylene, respectively, is applied.