In order to understand the role of Co catalysts with different phases on Fischer-Tropsch synthesis, single-phase face-centered cubic (fcc) and hexagonal close-packed (hcp) Co were synthesized via a two-step approach, involving the formation of single-phase CoO materials followed by reduction in H2. The physicochemical properties of Co catalysts were thoroughly characterized by XRD, SEM, TEM, TPR and H2 chemisorption. It was found that hcp-Co exhibits higher activity on hydrocarbon formation than fcc-Co in Fischer-Tropsch synthesis. For both catalysts, CO dissociation was suggested as the rate determining step, on which hcp-Co presents ca. 40 kJ mol-1 lower activation energy than fcc-Co, in agreement of reported computational study. As a result, hcp-Co is concluded as a preferable phase for rational catalyst design.
Revised: January 29, 2019 |
Published: September 7, 2018
Citation
Lyu S., L. Wang, J. Zhang, C. Liu, J. Sun, B. Peng, and Y. Wang, et al. 2018.Role of Active Phase in Fischer-Tropsch Synthesis: Experimental Evidence of CO Activation over Single-phase Cobalt Catalysts.ACS Catalysis 8, no. 9:7787-7798.PNNL-SA-136500.doi:10.1021/acscatal.8b00834