Electroplated Palladium Catalysts on FeCrAlloy for Joule-Heat-Ignited Catalytic Elimination of Ethylene in Air

Palladium catalysts were electroplated onto Fe–Cr–Al alloy to build Joule-heat-ignition catalytic reactors for the complete oxidation of ethylene. The catalytic process involved directly passing electric currents through the alloy substrates to generate Joule heat, leading to a temperature increase in the supported catalysts and hydrocarbon ignition. The effects of alloy pretreatment and alumina washcoating on the Joule-heat-ignited catalytic performance were studied. The electroplated palladium catalyst supported on a calcined substrate exhibited better performance than that supported on either an anodized substrate or an untreated one, which can be attributed to the oxygen species generated in the interface between the palladium particles and the protruding oxide particles on the calcined substrate. Washcoating of the anodized substrate with alumina prior to electroplating with palladium improved the catalytic activity, which could also be due to the presence of palladium–alumina interfaces. The facile electroplating method and the Joule-heat-ignition catalytic system can be applied in catalytic processes using metallic monoliths as substrates.