Vacuum distillation refining of crude lithium (II) - Kinetics on vacuum distillation of crude lithium

Kinetics on vacuum refining process of crude lithium was studied by using maximum evaporation rate, critical pressure and mean free path of elements in the crude lithium at different temperatures. Behaviors of impurities in the vacuum distillation process have been examined in detail. The results show that fractional vacuum distillation should be taken to obtain lithium with high purity; if the mass loss amount of lithium is 3%similar to5%, metal K, Na, Mg and Ca can be eliminated at lower temperature of 673similar to873 K at pressure of less than 1.30 Pa; the maximum rate of lithium distillation reaches 1.492 x 10(-1)similar to8.244 x 10(-1) g.cm(-2).min(-1) at higher temperature of 973similar to1073 K at the pressure of 3.0similar to3.2 Pa, which ensure complete separation of lithium from Ai, Si, Fe and Ni.