CO2 hydrogenation to methanol on Pd[sbnd]Cu bimetallic catalysts with lower metal loadings

Abstract

A series of PdCu bimetallic catalysts with a wide range of total loadings (i.e., 2.4–18.7 wt%, Pd/(Pd + Cu) = 0.34 at at−1) were prepared and evaluated for CO2 hydrogenation to CH3OH (Methanol). A key observation is the retention of bimetallic promotion of CH3OH at lower metal loadings. Pd-Cu(2.4)/SiO2, which contains the lowest metal loading, yields ~1.6× more CH3OH than the commercial Cu-ZnO-Al2O3 catalyst with respect to metal-based space-time yield (STY) at 523 K and 4.1 MPa. However, an enhancement in CO production is realized. Combined with the characterization results, the size effect-surface alloy composition-catalytic performance relationship was discussed. This work provides insights in designing cost-effective PdCu catalysts with lower metal loadings for CH3OH synthesis via CO2 hydrogenation.