Separation and recovery of rare earths via a dry chemical vapour transport based on halide gaseous complexes

The progress in the field of mutual separation of rare earths from the rare earth ores and their recovery from rare earth containing industrial waste by the dry chemical vapour transport (CVT) process mediated by the corresponding gaseous rare earth complexes with aluminum or alkali chlorides, RAI_nCl_3+3n or KRCl₄, is reviewed and discussed on the basis of their thermodynamic characteristics. The experimental results for the mutual separation and recovery of rare earth elements show the potential of this simple dry CVT process to substitute the conventional energy consuming complicated wet methods used at present for the costly preparation of the rare earths.