Phase Diagram of the System LaCl₃-CaCl₂-NaCl

Abstract

The phase diagram of ternary system LaCl 3 -CaCl 2 -NaCl has been constructed from the phase diagrams of the three binary systems and of thirteen quasi-binary systems determined by DTA. For the binaries LaCl 3 -CaCl 2 and CaCl 2 -NaCl eutectic points were observed at 651 °C , 35.1 mol% LaCl 3 and at 508 °C , 49.9 mol% NaCl, respectively. For LaCl 3 -NaCl, a peritectic point besides the eutectic point at 545 °C , 36.1 mol% LaCl 3 was found at 690 °C , 57.5 mol%, which is attributable to the formation of the peritectic compound 3 LaCl 3 · NaCl. The phase diagram of the ternary system has a ternary eutetic point and a ternary peritectic point due to 3 LaCl 3 -NaCl, the form er at 462 °C and 12.1 - 3 9 .7 - 4 8 .2 mol% (LaCl 3 -CaCl 2 -NaCl) and the latter at 612 °C and 26.9 - 55.1 - 18.0 mol%.