GB627286A - Process for producing rare earth metals - Google Patents

Abstract

In a process for producing metals or alloys of metals of the rare earth series, extending in the order of increasing atomic number from lanthanum to lutecium and including yttrium, which are substantially free from impurity other than magnesium, an alloy of the said metal or metals with magnesium is produced and said alloy is submitted to a distillation to separate practically all the magnesium. The magnesium alloy may be obtained by melting magnesium in the presence of one or more salts of elements of the cerium or yttrium groups to which one or more halides such as alkali metal chlorides have been added. This process may be modified by increasing the specific gravity of the rare earth metal alloy through previously alloying the magnesium with a heavy metal such as zinc or cadmium, which may subsequently be separated from the rare earth metal or alloy by distillation. The magnesium may be distilled in vacuum or in the presence of an inert gas such as argon. Alloys to which reference is made contain respectively 10.7 to 11 per cent or 8 per cent neodymium, 10.5 per cent or 8.6 per cent gadolinium, and 10 per cent cerium, the balance in each case being magnesium.