Drying method for exhaust gas catalyst

A method for preparing an exhaust gas catalyst includes preparing a washcoat comprising a catalytically effective amount of at least one catalytically active metal disposed upon an oxide support; disposing the catalytically active metal-oxide support washcoat upon a catalyst substrate; drying the washcoated catalyst substrate using microwave energy to affix the precious metals to the oxide support; and conventionally calcining the dried washcoated catalyst substrate. The catalysts comprising a substrate having dispersed thereon an inorganic oxide washcoat, the washcoat having been affixed to the substrate by microwave drying, exhibit high exhaust gas purifying performance and long durability. The catalysts thus produced further provide a long in-service lifetime for reforming organic fuel species into hydrogen, carbon monoxide and light hydrocarbons used in the nitrogen oxides reduction process.