Cu/REO (RE = La, Pr, Sm, Y, Ce) catalysts for methanol steam reforming: Understanding the interaction between Cu and individual REO supports

Abstract

With the objective to develop applicable catalysts for methanol steam reforming (MSR) to generate H 2 , five individual REOs were prepared as supports for Cu/CuO to understand the Cu/CuO-support interaction. Pure REO supports with a cubic phase are successfully fabricated except that monoclinic La 2 O 2 CO 3 carbonate is formed for La 2 O 3 sample, which has negative effect on the reaction. The reaction performance ranks as 5 % Cu/CeO 2 > 5 % Cu/Sm 2 O 3 > 5 % Cu/Pr 6 O 11 > 5 % Cu/Y 2 O 3 > 5 % Cu/La 2 O 3 for the samples. It has been disclosed that the quantities of surface basic sites, active O 2 – species, Cu + contents/percentage and active Cu surface area are positively correlated to the reaction performance. Thus, the interaction together of these four factors decides the reaction performance. In addition, In-situ DRIFTS results of CH 3 OH adsorbing/steam reforming have demonstrated that on the optimal 5 % Cu/CeO 2 , the reactive monodentate m-HCOO* intermediate is formed, which is absent on 5 % Cu/Y 2 O 3 with worse performance.