Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (6): 1137-1144.doi: 10.3866/PKU.WHXB201503311

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Fischer-Tropsch Synthesis over Skeletal Co@HZSM-5 Core-Shell Catalysts

XU Ke1, CHENG Yi1, SUN Bo1, PEI Yan1, YAN Shi-Run1, QIAO Ming-Hua1, ZHANG Xiao-Xin2, ZONG Bao-Ning2   

  1. 1 Collaborative Innovation Center for Energy Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Shanghai 200433, P. R. China;
    2 State Key Laboratory of Catalytic Materials and Reaction Engineering, Research Institute of Petroleum Processing, China Petroleum & Chemical Corporation, Beijing 100083, P. R. China
  • Received:2015-02-02 Revised:2015-03-31 Published:2015-06-05
  • Contact: QIAO Ming-Hua, ZONG Bao-Ning E-mail:mhqiao@fudan.edu.cn;zongbn.ripp@sinopec.com
  • Supported by:

    The project was supported by the National Key Basic Research Program of China (973) (2012CB224804), National Natural Science Foundation of China (21373055), and Science and Technology Commission of Shanghai Municipality, China (08DZ2270500).

Abstract:

We used skeletal Co as the core to prepare a skeletal Co@HZSM-5 core-shell catalyst by growing an HZSM-5 membrane on skeletal Co via hydrothermal synthesis. The physicochemical properties of the catalyst were determined using elemental analysis, N2 physisorption, X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and NH3 desorption. In gas-phase Fischer-Tropsch synthesis (FTS), the skeletal Co@HZSM-5 core-shell catalyst was more efficient than a physically mixed skeletal Co-HZSM-5 catalyst in cracking long-chain hydrocarbons, giving higher selectivity for C5-C11 gasoline products. The thickness of the zeolite shell on the skeletal Co@HZSM-5 core-shell catalyst was easily tuned by adjusting the hydrothermal time. At a suitable zeolite shell thickness, the long-chain hydrocarbons were cracked completely, with high FTS activity, leading to high selectivity for the gasoline fraction. Increasing the reaction temperature resulted in higher FTS and cracking activities, but the product distribution shifted to short-chain hydrocarbons. For the optimum skeletal Co@HZSM-5 core-shell catalyst, which was subjected to hydrothermal treatment for 4 d, selectivity for the gasoline fraction reached 79% at 250 ℃, which shows an excellent synergistic effect between the FTS active sites and the acidic sites on this catalyst.

Key words: Skeletal Co, HZSM-5, Zeolite, Core-shell structure, Fischer-Tropsch synthesis

MSC2000: 

  • O643