A process for direct chlorination of rare earth ores at high temperatures on a production scale

Abstract

A process for direct chlorination of rare earth ores without the necessary preparation of carbides or other intermediate compounds is described. Complete chlorination of all non-volatile components of the ores is obtained in a special, electrically heated furnace at temperatures between 1000 and 1200°C. The construction of the furnace permits quick replacement of some important components while the furnace is still hot. This reduces the unavoidable corrosion problem. The flowsheet of the process is presented. The process permits a high productive capacity with a small space, low investment, and low labor input. It is possible to process the most varied ores, such as Bastnasite, Monazite, Allanite, Cerite, Xenotime, Euxenite, Fergusonite, Gadolinite, etc., in the same installation. Reference is made to the treatment of off-gases. Fused anhydrous rare earth chlorides, without contaminants, are obtained as the final product, which is very suitable for the production of rare earth metals. This process can also be used to convert pure rare earth oxides to anhydrous chlorides.