| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for recovering the fluorine-containing emulsifier from the wastewater left after the coagulation of a fluoropolymer. SOLUTION: The method for recovering a fluorine-containing emulsifier comprises adjusting the wastewater left after the separation of a fluoropolymer obtained by polymerizing a fluoromonomer in an aqueous medium containing a fluorine-containing emulsifier, containing 1-10 ppm mass fluorine-containing emulsifier, and having a content of suspended solid matter and a substance convertible thereinto of at most 1 mass% to a pH equal to the pH at which the below mentioned layered double hydroxide is formed by using the above mentioned layered double hydroxide containing an intermediate layer of anions other than the fluorine-containing emulsifier among the metal hydroxide layers comprising divalent metal ions and trivalent metal ions and adding the layered double hydroxide in such an amount that 1-30 mole of the trivalent metal ions in the layered double hydroxide are present per mol of the fluorine-containing emulsifier to the wastewater to include the fluorine-containing emulsifier among the layers of the layered double hydroxide, separating the layered double oxide emulsifier from the wastewater, and recovering the fluorine-containing emulsifier. COPYRIGHT: (C)2003,JPO
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