Study of nickel catalysts for hydrogen production in sorption enhanced reforming process

Abstract The performance of Ni based catalysts to be used in Sorption Enhanced Reforming (SER) is assessed. For this aim, both their activity at low temperature and their behavior during multiple oxidation–reduction cycles in steam methane reforming are studied. Ni catalysts supported on α-Al 2 O 3 , Si 3 N 4 and NiAl 2 O 4 , with different amounts of Ni (0–50% NiO), are compared by testing their activity in a fixed bed micro-reactor. While Ni/Si 3 N 4 catalysts do not show an appropriate performance at low temperature, Ni/α-Al 2 O 3 and Ni/NiAl 2 O 4 present a significant activity, close to equilibrium data, at the typical SER conditions. The best experimental results are attained for 20% NiO/α-Al 2 O 3 and 10% NiO/NiAl 2 O 4 catalysts that show an activity close to the equilibrium for steam to methane ratio of 4.5. Higher amounts of NiO in both catalysts do not reveal an improvement in conversion results. In addition, both 20% NiO/α-Al 2 O 3 and 10% NiO/NiAl 2 O 4 catalysts show a good reforming activity after oxidation–reduction cycles at typical SER temperatures. The observed trend to carbon deposition on the catalyst surface for the studied supports is Si 3 N 4  > Al 2 O 3  > NiAl 2 O 4 , being negligible when NiAl 2 O 4 support is used. These results suggested that 10% NiO/NiAl 2 O 4 and 20% NiO/Al 2 O 3 catalysts could be perfect candidates to be used in SER process.