摘要 |
Catalyst bonded directly to a metal surface used for heating the reaction mixt. is made by (A) producing a highly porous metal sponge from powder by known sintering methods, (B) impregnating the sponge with salts and calcining to give >=1 non-reducible oxide (esp. Al2O3) and >=1 reducible oxide (esp. NiO) in combined amount not greater than the wt. of sponge, and (c) reducing the second oxide in the porous layer. The sponge layer is pref. made by >=2 sintering operations, with the finer powder bonded to the metal surface. Catalyst is used in steam-reforming of hydrocarbons, esp. methane, to CO/H2 mixts. and the reverse reaction for methanisation of CO/H2 mixts. Activity is at least as good as known catalysts on ceramic carriers, and thermal conductivity is much improved. The metal sponge gives high strength and adhesion e.g. to the metal walls of reforming reactor tubes. Recrystallisation of the active catalyst is prevented by the non-reducible oxide, which also determines the surface area. |