Abstract
•Acetone steam reforming on MNi/Al2O3-La (M=Pt or Cu) catalysts has been studied.•CuNi catalyst shows acetone reforming activity lower than the monometallic Ni.•High reforming activity and stability was achieved over PtNi catalyst.•Activity of PtNi is associated with a better Ni dispersion and enhanced mobility of H-atoms.
The effect of Pt and Cu addition on the behaviour of Ni catalysts supported on Al2O3 modified with La for acetone steam reforming (as model molecule of bio-oil) was studied. Catalytic activity was found to depend strongly on the bimetallic formulation, achieving the bimetallic PtNi catalyst almost complete gasification of the acetone. The characterization results achieved with XRD, TPR and XPS showed differences in surface metal concentrations which depend on the presence of Pt or Cu in catalysts composition. The decrease in activity observed for the bimetallic CuNi catalyst is associated with changes in the acetone reaction mechanism due to the presence of metallic copper since formation of CuNi alloy was not formed in this catalyst. In the case of bimetallic PtNi catalyst, a lower carbon deposition and a higher thermal stability of the Ni crystallites under reaction conditions was observed with respect to monometallic Ni reference catalyst. It is suggested that the better dispersion of metallic nickel crystallites together with the enhanced H-atom mobility on Pt are responsible of the better catalytic behaviour of the bimetallic PtNi formulation in the steam reforming of acetone.