Hydrogen production by aqueous phase reforming over stable La-promoted Ni-based hydrotalcite catalysts

Methanol, a common product of biomass pyrolysis or gasification, contains a high hydrogen content and serves as a valuable feedstock for hydrogen production through catalytic aqueous phase reforming (APR). However, poor hydrothermal stability of metal oxides support of the APR catalyst in liquid phase presents a challenge for the continuous and effective production of H2 over Ni-based hydrotalcite catalysts. A series of La-promoted NiMgAl hydrotalcite catalysts were prepared and their hydrogen production performances during methanol APR were evaluated. Promoted 5La–NiMgAl catalyst shows superior methanol APR reactivity due to the higher concentration of medium-strength basic sites than unpromoted catalyst. The La species adsorbs CO2 to form LaCO3OH and maintains La–NiMgAl catalyst structural integrity, which limits Ni leaching during reaction and promotes catalyst stability.