Perfluorocarbon emissions from electrolytic reduction of rare earth metals in fluoride/oxide system

Özet

Perfluorocarbons (PFC) are important greenhouse gas. In the aluminum electrolysis industry, PFCemission had been valued. The electrolytic reduction of rare earth metals in fluoride/oxide system withcarbon anode and tungsten cathode also has PFC emission. But the PFC emission in rare earth metalsindustry received less attention. The PFC emissions during the electrolysis were studied by tracking thechange of CF4 concentration in the flue gas of neodymium electrolysis and dysprosium-iron alloy electrolysis.The results showed that there were continuous CF4 overflows in the electrolysis process. The CF4was outburst when anode effect occurred. The anode effect was always accompanied with the lowelectrolysis temperature. In addition, because of the electrolytic dysprosium-iron alloy requires highercell voltage, the PFC emissions are higher than rare earth electrolysis. In general, PFC emissions from rareearth metal electrolysis are quite same as the aluminum electrolysis industry.