Production process of polyphenylene ether

A process for producing a polyphenylene ether, which comprises:

• contacting, with an aqueous solution of a chelating agent, a polyphenylene ether solution obtained by polymerization in a non-water-soluble polymerization solvent for a polyphenylene ether in the presence of a catalyst, to terminate the polymerization and deactivating the catalyst;
• and
• adding a water-soluble poor solvent for the polyphenylene ether to precipitate the polyphenylene ether;
• and
• recovering the thus precipitated polyphenylene ether,
• wherein (a) the contact with the chelating agent aqueous solution is carried out by holding the polyphenylene ether solution and the chelating agent aqueous solution at a temperature of from 50 to 120° C. for 10 to 180 minutes,
• wherein (b) a mixture remaining after the recovery of the polyphenylene ether, which contains the non-water-soluble polymerization solvent and water-soluble poor solvent, is brought into contact with water to extract the water-soluble poor solvent, and a water phase containing the thus extracted water-soluble poor solvent is recovered by separation, and
• wherein (c) the water-soluble poor solvent is separated and removed from the water phase by distillation, and the whole or a part of the remaining water phase is recycled as water to be brought into contact with the mixture, the remaining water phase having a content of a high-boiling-point organic substance of 1 wt. % or less.