Process for the manufacture of alkali metal hydrides in coarse powder form

Alkali metal hydrides, obtained by reacting alkali metals in liquid form with hydrogen in the presence of alkali metal hydrides, are obtained in coarsely crystalline form by continuously introducing into the reaction vessel containing constantly agitated alkali metal hydride only so much alkali metal in liquid form which corresponds stoichiometrically to the amount of hydrogen reacted and maintaining the unreacted metal concentration at 3 weight percent or less of the pre-introduced metal hydride present. In preferred aspect, the pre-introduced metal hydride is agitated by mixing means at a circumferential velocity of 0.5 to 2 meters/second and maintained at 250 DEG -310 DEG C., to yield hydride crystals in the range of 100 to 1000 microns. The hydride thus obtained may be ground in an inert hydrocarbon mixture to a finer particle material still having a relatively low surface area and recovered as a stabilized, non-sticking, non-self ignitable alkali metal hydride product.