Morphology-Dependent Catalytic Activity of ZnFe2O4 Spinel Toward Light Olefins from Fischer–Tropsch Synthesis

Abstract

The shape-defined ZnFe₂O₄ spinel with cubic and octahedral morphology was hydrothermally synthesized, respectively, and used as catalyst precursor for Fischer–Tropsch synthesis (FTS). The structure of ZnFe₂O₄ spinel was changed to ZnO and Fe₅C₂ (Fe₅C₂/ZnO) after reduction and carbonization. Interestingly, ZnFe₂O₄ with cubic morphology exhibited much higher catalytic activity and selectivity toward low-carbon olefins (C₂–C₄) than the octahedral one under identical conditions, and the latter tended to produce the saturated alkanes. The primary properties of ZnFe₂O₄ materials before and after reduction were systematically studied through a series of characteristic technologies to reveal the difference in catalytic performance between the two ZnFe₂O₄ spinels with different morphologies.