Preparation of Anhydrous LnCl3(Ln=Eu, Er, Lu) by Chemical Vapor Transport

Anhydrous lanthanide chlorides LnCl3(Ln=Eu, Er, Lu) which are not easy to prepare in other ways were prepared by chemical vapor transport(CVT) method. Ln2O3 reacted with an excess of Al2Cl6 at 300 ℃ to produce LnCl3. LnCl3 reacted with Al2Cl6 at high temperature to form the gaseous complexes which decomposed at low temperature. LnCl3 was then separated from other solids by controlling a proper temperature gradient. Residual Al2Cl6(g) was removed by the carrier of dry Cl2-N2 gases at 200 ℃. The yield rates are >90%, and the purity of products is >99.5%. The high purity of anhydrous lanthanide chlorides can be obtained by CVT method.