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The United States Environmental Protection Agency defines PFAS in the Drinking Water Contaminant Candidate List 5 as substances that contain "at least one of the following three structures: R−CF 2 −CF(R')R", where both the −CF 2 − and −CF− moieties are saturated carbons, and none of the R groups can be hydrogen; R−CF 2 −O−CF 2 ...
Fluorosurfactants (PFAS) reduce surface tension by concentrating at the liquid-air interface due to the lipophobicity of polyfluorocarbons. Chlorofluorocarbons are also perfluorinated compounds, many of which were formerly used as refrigerants ( Freon ) until they were implicated in ozone degradation .
Remediation of per- and polyfluoroalkyl substances refers to the destruction or removal of per- and polyfluoroalkyl substances (PFASs) from the environment. PFASs are a group of synthetic organofluorine compounds, used in diverse products such as non-stick cookware and firefighting foams, that have attracted great concern as persistent organic pollutants.
This list is sorted by boiling point of gases in ascending order, but can be sorted on different values. "sub" and "triple" refer to the sublimation point and the triple point, which are given in the case of a substance that sublimes at 1 atm; "dec" refers to decomposition. "~" means approximately. Blue type items have an article available by ...
The F-gas Regulation adopts an approach based on containment and recovery of F-gases as well as imposing obligations on reporting, training and labeling on those using F-gases. On 26 September 2011, the Commission issued a report on the application, effects and adequacy of the Regulation, drawing from the results of an analytical study it ...
Perfluoroalkanes are very stable because of the strength of the carbon–fluorine bond, one of the strongest in organic chemistry. [4] Its strength is a result of the electronegativity of fluorine imparting partial ionic character through partial charges on the carbon and fluorine atoms, which shorten and strengthen the bond (compared to carbon-hydrogen bonds) through favorable covalent ...
ECF is an electrolysis method whereby the precursor of octanesulfonyl fluoride is electrolyzed in a solution of hydrogen fluoride to give perfluorooctanesulfonyl fluoride. This production method also results in shorter chain perfluoroalkyl substances being formed. [citation needed] PFOS predominates in the resultant mixture. A distinct isomer ...
Alkenes react with hydrogen chloride (HCl) to give alkyl chlorides. For example, the industrial production of chloroethane proceeds by the reaction of ethylene with HCl: [citation needed] H 2 C=CH 2 + HCl → CH 3 CH 2 Cl. In oxychlorination, hydrogen chloride instead of the more expensive chlorine is used for the same purpose: