Solid solutions of the transition metals nitrides and oxynitrides and methods of preparation thereof

摘要

1,126,813. Nitrides and oxynitrides. CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE. 26 Nov., 1965 [27 Nov., 1964], No. 50277/65. Heading C1A. [Also in Division B1] Solid solutions of nitrides and oxynitrides containing 2 to 7 of the metals Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W are prepared by formng powders of the corresponding, oxides and reacting with a NH 3 -containing gas at temps. from 600‹ to 1500‹ C. The gas may also contain H 2 . The powdered oxides may be formed' by (a) coprecipitation of a solution containing salts or unstable complexes of 2 to 7 of the metals with NH 3 or urea, or (b) co-crystallizing; oxalate. complexes of the metals, then pyrolysing the hydrated metal oxides or oxalate complexes at a temp. less than 700‹ C. in an atmosphere of NH 3 with or without H 2 . The nitrides produced may contain up to 10% wt. of interstitial oxygen and are termed oxynitrides.. The particles of this product may be submicronic. The nitriding reaction may be performed in a fixed or fluidized bed. The product may be used as catalyst in the synthesis of NH 3 or as a catalyst support.