Patent GB-1009895-A (GB)
Title: Process for the production of a catalyst
IPC: H01M4/88
Filed: 1961-12-14
Abstract: A catalyst for a reaction based on hydrogen transfer or ionization is obtained by impregnating a body having a porosity of at least 30% and comprising one or more metals and/or metal alloys which are stable in alkaline solution and which are capable of incorporating hydrogen in their crystal lattice, with an alkaline solution of a reducing agent which, upon contacting the metal, decomposes with the liberation of hydrogen.  Alkaline solutions of complex hydrides, e.g. borohydrides and particularly alkali metal borohydrides, or aluminohydrides, preferably lithium aluminohydride may be used as reducing media. Hydrazine and hydroxylamine or the salts thereof may also be used. The metals of sub-groups IB, IVA, VA, VIA and VIII of the Mendeleef Periodic Table are suitable metals for the porous body, the preferred metals being silver, copper, titanium, zirconium, hafnium, thorium, vanadium, niobium, tantalum, chromium, iron, cobalt, nickel and the platinum metals.  The impregnation of the porous body is preferably effected at a temperature between 10 DEG  and 60 DEG  C.  By eliminating the alkaline solution of the reducing agent, e.g. with water at least a substantial amount of hydrogen embedded in the lattice of the metal may be removed.  In the examples:  (1) A carbonyl nickel powder, a sintered cobalt body and a sintered cobalt-nickel body are separately treated with a sodium borohydride solution in potassium hydroxide; (2) A cobalt-nickel alloy is treated with a lithium aluminohydride solution and (3) Nickel powder is treated with an alkaline hydrazine sulphate solution.ALSO:A catalyst for a reaction based on hydrogen transfer or ionization e.g. for hydrogenation and dehydrogenation reactions and for use in galvanic cells, preferably in fuel cells, is obtained by impregnating a body having a porosity of at least 30% and comprising one or more metals and/or metal alloys which are stable in alkaline solution and which are capable of incorporating hydrogen in their crystal lattice, with an alkaline solution of a reducing agent which, upon contacting the metal, decomposes with p  the liberation of hydrogen.  Alkaline solutions of complex hydrides e.g. borohydrides and particularly alkali metal borohydrides, or aluminohydrides, preferably lithium aluminohydride, may be used as reducing media.  Hydrazine and hydroxylamine or the salts thereof may also be used.  The metals of Sub-Groups of Ib, IVa, Va, VIa and VIII of the Mendeleef Periodic Table are suitable metals for the porous body, the preferred metals being silver, copper, titanium, zirconium, hafnium, thorium, vanadium, niobium, tantalum, chromium, iron, cobalt, nickel and the platinum metals.  The impregnation of the porous body is preferably effected at a temperature between 10  DEG C. and 60  DEG C.  By eliminating the alkaline solution of the reducing agent e.g. with water, at least a substantial amount of hydrogen embedded in the lattice of the metal may be removed.  In the examples: (1) A carbonyl nickel powder, a sintered cobalt body and a sintered cobalt-nickel body are separately treated with an alkaline sodium borohydride solution; (2) A cobalt nickel alloy is treated with a lithium alumino-hydride solution, and (3) a nickel powder is treated with an alkaline hydrazine sulphate solution.