Catalysis Today, Vol.299, 303-316, 2018
Intermetallides as the catalysts for carbon dioxide reforming of methane
Intermetallic catalysts for dry reforming of methane (DRM) based on Ni3Al with low content of Pt and Ru have been developed. Self-propagating high-temperature synthesis (SHS) was used as a method of catalyst synthesis. Ion implantation was used to change the physical, chemical and catalytic properties of Ni3Al as a matrix for this new type of catalysts for DRM. Ions of Pt and Ru were accelerated in an electrical field and impacted into a solid Ni3Al. The catalytic performances were evaluated between 600 degrees C and 900 degrees C at atmospheric pressure. The feed was CH4/CO2/He = 20/20/60 vol.% mixture. Particle size and chemical evolution of catalysts were studied by XRD (in situ and ex situ), SEM, EDS, HRTEM + EDS and XPS. The active components were shown to be primarily dispersed in the nearsurface layer of Ni3Al support as nanoparticles of size 5-10 nm, which were distributed homogeneously or heterogeneously, depending on the catalyst composition. Spinel structure of some catalysts is resistant to carbonization and provides high catalyst stability in DRM. Modification of catalyst by ion implantation had several positive impacts: 1) high catalytic activity and stability in DRM, 2) reducing of carbon deposits, 3) Pt and Ru prevent Ni phase sintering by avoiding particle coalescence.
Keywords:Dry reforming of methane;Intermetallic;Self-propagating high-temperature synthesis;Ion implantation;Platinum;Ruthenium