Fig. 4: Catalytic performance and surface chemistry of ZnCr2O4@ZnOx catalysts.
From: ZnOx overlayer confined on ZnCr2O4 spinel for direct syngas conversion to light olefins
a Catalytic performance of ZnCr2O4 and ZnCr2O4@ZnOx catalysts coupled with SAPO-34. Reaction conditions: 0.20 g ZnCr2O4@ZnOx + 0.10 g SAPO-34, 68% H2 + 27% CO + 5% Ar, 4.0 MPa, 15 mL·min−1, 40–60 mesh, 400 °C. CO2 selectivity does not change with the ZnO loading and is in the range of 38–41% for each catalyst. b Relationship between surface Ov concentration, amount of adsorbed CO, and ZnO loading of ZnCr2O4@ZnOx catalysts. c Relationship between HD formation rate and ZnO loading of ZnCr2O4@ZnOx catalysts. The pretreated ZnCr2O4@ZnOx catalysts were exposed to a flow of 10% D2, 10% H2, and 80% Ar, and the formation of HD species was detected at 400 °C. d Scheme of the active sites on ZnCr2O4@ZnOx catalysts.
