| 摘要 |
PURPOSE:To enable the melt treatment of a rare earth ore near the melting point of caustic alkali and the decomposition of a rare earth ore irrespective of the material of the reactor, by carrying out alkali metal decomposition of a rare earth ore with caustic alkali in the presence of an oxidizing agent. CONSTITUTION:A rare earth ore is subjected to molten alkali decomposition with caustic alkali in the presence of an oxidizing agent. Any ore containing rare earth elements in an industrially valuable amount may be used as the rare earth ore in the present process, however, the ore is usually selected from concentrates of monazite, bastnaesite, xenotime and their mixture. The caustic alkali is caustic soda or caustic potash, among which inexpensive caustic soda is preferable for industrial use. The weight ratio of the caustic alkali to the ore is about 2-10 to proceed the decomposition while keeping the fluidized state of the reaction. The oxidizing agent used in the process is preferably oxygen, an oxygen-containing gas, inexpensive alkali nitrate or alkali nitrite.
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