The metallothermy and electrowinning of molten lanthanide chlorides as a method for production of light rare earth metals and their alloys were investigated. The new process -“soft” metallothermic reduction of rare earth chlorides with calcium was developed. The complete installation for production of light lanthanide metals and their alloys at large laboratory scale was constructed. This installation gives the possibility of production of lanthanum, cerium, praseodymium and mischmetal as well as light lanthanide alloys with iron, zinc and aluminium at 1 kg scale with efficiencies of about 95 - 98 %.
The main steps of technology of lanthanide metals production are as follows:
- production of anhydrous lanthanide chlorides by wet or dry methods
- melting of anhydrous lanthanide chlorides in a gaseous hydrogen chloride atmosphere
- electrolysis or metallothermic reduction of lanthanide chlorides
- recovery of rare earth chlorides from the salt after electrolysis or metallothermy
- utilisation of gaseous products from the production process (chlorine, hydrogen chloride).