Enhanced catalytic activity of Ni3Al foils towards methane steam reforming by water vapor and hydrogen pretreatments

Abstract

A pretreatment procedure consisting of water vapor oxidation followed by H2 reduction has been developed for enhancing the catalytic activity of as-rolled Ni3Al foils for steam reforming of methane. The catalytic activities of the as-rolled Ni3Al foils in the temperature range of 873–1023 K at a steam to carbon ratio of 1.0 were found to be significantly improved by the pretreatment procedure consisting of a water vapor oxidation at 873–923 K for 1 h followed by a H2 reduction at 873 K for 1 h. Surface characterization of the foils before and after the reactions revealed that many fine NiO particles were formed on the surface by the water vapor oxidation at 873–923 K, whereas much less NiO particles were formed by the water vapor oxidation at low temperatures (<873 K) or high temperatures (>973 K). During the subsequent H2 reduction treatment at 873 K, These NiO particles were reduced to metallic Ni. It is supposed that the enhancement in catalytic activity is attributed to the fine metallic Ni particles formed on the foil surface by the pretreatment procedure.