Abstract: The present invention provides a novel method for producing hexafluoropropylene oxide, which can attain a high HFPO selectivity without using a phase transfer catalyst. Hexafluoropropylene (HFP), a water-soluble and aprotic organic solvent, and an aqueous solution of an oxidizing agent are introduced into a small space, thereby bringing into contact with each other and reacting hexafluoropropylene with the oxidizing agent to obtain hexafluoropropylene oxide (HFPO).

Abstract: The present invention provides a novel method for separating hexafluoropropylene oxide (HFPO) from hexafluoropropylene (HFP), which is capable of reducing the burden on the environment. A mixture including HFPO and HFP is subjected to an extractive distillation operation using, as a solvent, at least one of a fluorine-containing saturated compound represented by the general formula CnHaFb (wherein n, a and b are integers which satisfy: n=3 to 8, 0?a?2n+1, and 1?b?2n+2) thereby separating into a first fraction including HFPO and a second fraction including HFP and the solvent. At least one of 1-bromopropane and 2-bromopropane may be u as the solvent in place of the fluorine-containing saturated compound.

Abstract: The present invention provides a method for efficiently producing a highly pure fluoroether containing remarkably low concentration of a fluorine-containing alkyl alcohol. The method is suited for scale-up and specifically includes performing countercurrent separation of a crude solution of fluoroether including a fluorine-containing alkyl alcohol as an impurity using water.

Abstract: The present invention provides a novel method for producing hexafluoropropylene oxide, which can attain a high HFPO selectivity without using a phase transfer catalyst. Hexafluoropropylene (HFP), a water-soluble and aprotic organic solvent, and an aqueous solution of an oxidizing agent are introduced into a small space, thereby bringing into contact with each other and reacting hexafluoropropylene with the oxidizing agent to obtain hexafluoropropylene oxide (HFPO).

Abstract: The present invention provides a novel method for separating hexafluoropropylene oxide (HFPO) from hexafluoropropylene (HFP), which is capable of reducing the burden on the environment. A mixture including HFPO and HFP is subjected to an extractive distillation operation using, as a solvent, at least one of a fluorine-containing saturated compound represented by the general formula CnHaFb (wherein n, a and b are integers which satisfy: n=3 to 8, 0?a?2n+1, and 1?b?2n+2) thereby separating into a first fraction including HFPO and a second fraction including HFP and the solvent. At least one of 1-bromopropane and 2-bromopropane may be u as the solvent in place of the fluorine-containing saturated compound.

Abstract: The present invention provides a treatment method by which a fluorinated surfactant such as PFOA can be removed from water very efficiently. The treatment method includes a step (1) of contacting a water to be treated containing 100 to 10000 ppb of a fluorinated surfactant with an activated carbon and a step (2) of obtaining a treated water containing not more than 3.0 ppb of the fluorinated surfactant. The activated carbon comprises the particles capable of passing through a 75-?m filter of not smaller than 90% by mass of the total particles.