International Regulatory Trend and Development of Decomposition Techniques for Environmentally Persistent Organofluorine Compounds

Abstract

有機フッ素化合物は熱的，化学的に安定で，高い界面活性作用や低粘性，低屈折率等の優れた 性質を持つ。このため様々な産業あるいは消費者向けの用途があり，新材料の研究も盛んである。一方で環 境中に残留しやすく，廃棄物の分解処理も困難，さらにPFOS やPFOA と呼ばれる一部の化合物やその関 連物質には生体蓄積性があるという側面もある。本稿ではこのような有機フッ素化合物の製造や使用に係る 世界の規制動向と，最近我々が取り組んでいる先端フッ素材料に関する分解・再資源化反応の研究成果につ いて報告する。 Organofluorine compounds have been widely used in industrial and consumer applications, owing to their specific characters such as high thermal and chemical stability. After it became clear that some of them, particularly, per fluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA), bioaccumulate in the environment, international legal measures regarding the production, use, and import and export of several organofluorine compounds are being implemented. Hence, it is desirable to develop effective methodologies for decomposing these compounds to environmentally harmless species under mild conditions. If they could be decomposed to F – ions by means of environmentally benign techniques, the well-established protocol for the treatment of F – ions could be used: Ca2+ is added to the system to form CaF2, which is a raw material for hydrofluoric acid. Thus, the development of such techniques would allow for the recycling of fluorine resource, the global demand for which is increasing. We describe herein the international regulator y trend for organofluorine compounds. We also describe our developed methodologies for ef ficient decomposition of cutting-edge fluorinated materials (ionic liquid and polymers) to F – ions.