| 摘要 |
<p>1393221 Treating exhaust gas GOULD Inc 21 Aug 1973 [13 Nov 1972] 39617/73 Addition to 1388284 Heading F1B [Also in Division C7] A catalytic structure for reducing NO x gases in internal combustion engine exhaust comprises a heat resistant metallic substrate, e.g. an expanded metal foil sheet of Ni, Co or Fe base alloy containing Cr with or without Al, having a catalytic alloy of a Ni base material (pure Ni or Ni with up to 1.5% Co) and at least 0.1% Cu adherently deposited on at least part of its surface, wherein the weight ratio of Ni base material to Cu is at least 9 to 1. A substrate foil of 80% Ni and 20% Cr may be formed by electro-plating Ni with Cr and alloying by heating at 2200‹F for 2 hours, then expanded, prior to electro-plating first a Ni coating 0.000g inch thick then a Cu coating 0.0001 inch thick and alloying together and diffusion bonding by heating at 1900‹F for 2 hours. Alternatively an expanded wrought foil of 80% Ni and 20% Cr may be electro-plated with Ni alloy containing 2% Cu from a bath containing 200 g/1 NiSO 4 .6H 2 0, 15 g/l, NiCl 2 .6H 2 0, 75 g/l Na citrate and 1.5 g/l CuSO 4 .5H 2 0 at pH 4.5-5. The metal foil may be produced by electro-deposition, hot or cold working or powder metallurgy. The catalyst alloy may be formed by vapour deposition, flame spraying, slip casting or dry powder sintering.</p> |
