Synthesis and catalytic performance of single phase Co₂C catalyst for Fischer-Tropsch synthesis

Single phase Co₂C catalysts were prepared by carburizing Co with CO at 280℃ and 2 MPa for 48 h. X-ray diffraction (XRD), transmission electron microscopy (TEM), H₂ temperature-programmed reduction (H₂-TPR), and X-ray absorption spectroscopy (XAS) were carried out to explore the structure and composition of the prepared Co₂C samples. The Co₂C catalysts were also evaluated in the Fischer-Tropsch synthesis to study their stability and catalytic performance. It was interesting to observe that the CO conversion and the selectivity for C₅₊ products gradually increased, but the selectivity to methane decreased during the reaction. Comparing the fresh catalysts with used catalysts, it was easy to find that the used catalysts were the mixture of metallic Co and Co₂C. The newly generated metallic Co may lead to the changes of CO conversion and product selectivity during the reaction.