The Dissociation of Metal Halides in Electrical Discharges

Halides of the Group I and II metals are dissociated in microwave discharges to metals and halogens, and to unstable monohalides (which disproportionate to metals and dihalides) and halogens, respectively. Inert gases may be used as carriers, and if H 2 is employed hydrogen halides instead of halogens result. Up to 70% yields of metal have been obtained. Group III and rare earth halides give metals in good yields only when hydrogen is present, probably via disproportionation of lower halides. The apparatus is described briefly. Relative reaction rates for the lithium group compounds are given and the effect of power, partial pressure of halide, and pressure of carrier gas are shown.