Kinetics of lanthanum and praseodymium reduction from chlorides by calcium

Investigated are kinetic properties regularities of thermal reduction of LaCl3 and PrCl3 by calcium in a melt and solutions with KCl. Process peculiarities are defined by the medium composition. Their reduction in a melt takes place in a kinetic region; activation energy Esub(α) decreases in a course of a process from 20.3 up to 16.7 and from 19.0 up to 17.0 kcal/mol respectively; LaCl3 reaction order is from 0.7 up to 0.3; PrCl3 reaction order - from 0.6 up to 0.5, and calcium reaction order is near zero; Esub(α) magnitude of reduction of lanthanum and praseodymium chlorides out of KCl solution is 18.2 and 16.8 kcal/mol respectively. The medium (CaCl2 - in the first case) increases effective concentration of chlorides, KCl (in the second case) reduces them in steps