RARE EARTH METAL, RARE EARTH METAL ALLOY AND METHOD FOR THE PREPARATION OF SAME BY MOLTEN SALT ELECTROLYSIS

• Main Authors: MIAO, RUIYING, WANG, ZHIQIANG, LI, ZONGAN, ZHOU, LIN, ZHANG, XIAOWEI, LUAN, WENZHOU, ZHANG, ZHIQI, CHEN, DEHONG, GUO, XUYI
• Format: Patent
• Language: Chinese; English; French
• Published: 10.04.2014
• Subjects: ALLOYS; APPARATUS THEREFOR; CHEMISTRY; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; FERROUS OR NON-FERROUS ALLOYS; METALLURGY; PRETREATMENT OF RAW MATERIALS; PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY ORREFINING OF METALS; PRODUCTION AND REFINING OF METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

A rare earth metal and a rare earth metal alloy and a method for the preparation of these by molten salt electrolysis. In the method, the electrolyte is an alkali metal or the chloride-fused salt of an alkaline earth metal, the positive electrode is an inert electrode or graphite, the negative electrode is composed of a rare-earth metal oxide or a rare-earth metal oxide and the oxides of other alloy components and/or metal powders, and electrolysis is induced by the passage of a direct current. During the electrolytic process, the temperature of electrolysis is higher than the melting point of the rare earth metal alloy or of the rare earth metal produced, and lower than the melting point of the negative electrode; the surface layer of the negative electrode is in the first stage electrolyzed to a liquid metal film which accumulates to a certain volume before falling to the crucible at the bottom. The current density of the negative electrode is sufficient to separate out from said negative electrode the comp