Preparation of rare earth trichlorides by chemical transport with aluminium trichloride

The preparation of rare earth trichlorides by reaction of rare earth oxides with aluminium trichloride and their purification by means of chemical vapour phase transport with aluminium trichloride is described. By the method used especially rare earth doted rare earth trichlorides are obtainable in one step. The method furthermore allows a simple preparation of europium trichloride, which is not easy to prepare in another way. Two modifications of terbium trichloride can be prepared depending on the exact temperature conditions of the chemical vapour phase transport. (author)