Design of Rh@Ce0.2Zr0.8O2-Al2O3 nanocomposite for ethanol steam reforming

Rh(1 wt.%)@Ce0.2Zr0.8O2(10 wt.%)-Al2O3 nanocomposite has been investigated as active and thermally stable catalyst for ethanol steam reforming. Rh nanoparticles were synthesised by surfactant assisted route, using N-hexadecyl-N-(2-hydroxyethyl)-N,N-dimethyl ammonium bromide (HEAC16Br). Metal particles with average diameter of 2.1 nm were obtained at 0.53 Rh/HEAC16Br molar ratio, while increasing the amount of surfactant lead to formation of larger particles. The preformed Rh nanoparticles have been effectively embedded into a porous layer of nanocomposite oxides. Low temperature H2 chemisorption experiments and activity data confirm that most of the Rh atoms are accessible to the reaction mixture. The Ce0.2Zr0.8O2 mixed oxide inhibits the dehydration of ethanol to ethylene and favours the water gas shift reaction. The alumina ensures good thermal stability and high surface area of the catalyst. No significant deactivation is observed after repeated run-up and run-down experiments