A Novel Hierarchical RuNi/Al2O3–Carbon Nanotubes/Ni Foam Catalyst for Selective Removal of CO in H2-Rich Fuels

Abstract

A novel hierarchical RuNi/Al2O3–carbon nanotube/Ni foam (RuNi/Al2O3–CNTs/NF) catalyst is prepared from a RuNiAl-layered double hydroxide/CNTs/NF (RuLDH/CNTs/NF) precursor and applied in CO selective methanation (CO-SMET) for hydrogen purification. Results show that the RuNi/Al2O3–CNTs/NF hierarchical catalyst has an excellent catalytic performance toward CO-SMET (i.e., CO outlet concentration less than 10 ppm and CO-SMET selectivity greater than 50%) over a wide reaction temperature window of 190–250 °C. Furthermore, this catalyst also shows good catalytic stability during a long-term durability test (120 h). The excellent catalytic performance is mainly attributed to the high specific surface area and superior electronic conductivity of CNTs, the highly dispersed and thermally stable RuNi nanoparticles from the RuLDH precursor, and the good thermal conductivity of the NF substrate. Such a hierarchically structured catalyst proposed herein may open a new window in the efficient hydrogen purification for f...