| abstract |
Particles of alloys of a noble metal chosen from among iridium, osmium, palladium, platinum, rhodium and ruthenium, hereafter represented by M, with at least one non-noble metal chosen among silver, bismuth, cadmium, cobalt, copper, tin, germanium, indium, manganese, mercury, molybdenum, nickel, gold, lead, rhenium, thallium, tellurium, technetium, tungsten, vanadium and zinc, hereafter referred to as Me', and Me', representing at least one non-noble metal, characterized in that they correspond to the general formula n n M.sub.n Me'.sub.m n n where n represents an integer equal to 1, 2 or 3 and where m represents an integer equal to 1, 2 or 3, and in that their specific surface area is between 0.5 and 800 m 2 /g of alloy and in that the mean diameter of the alloy particles is between 10 and 10,000 A. n The particles are prepared by reducing the mixed oxides of the corresponding formula n n M.sub.n Me'.sub.m O.sub.x n n They are used as catalyst for dehydrogenation or hydrogenation. |