The effects of metallic cobalt crystal phase on catalytic activity of cobalt catalysts in the Fischer–Tropsch synthesis were investigated in a continuous spinning basket reactor. The cobalt catalysts were prepared by impregnation of the cobalt active phase in a microemulsion system on multiwall carbon nanotube supports. A series of cobalt catalysts with different Co particle sizes was prepared by variation of the water-to-surfactant molar ratio from 2 to 12 in the microemulsion system. The X-ray diffraction results validate a complex composition of cobalt phases containing cobalt oxides and metallic cobalt with hexagonal close-packed and face-centered cubic phases. The results show that larger cobalt particles exhibit more face-centered cubic and less hexagonal close-packed metallic cobalt. The experimental results show that the catalysts with higher fractions of hexagonal close-packed phase exhibited higher conversion in the Fischer–Tropsch reaction.

中文翻译：

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金属钴晶相对费托合成中碳纳米管负载钴催化剂催化活性的影响

在连续旋转篮式反应器中研究了金属钴晶相对费-托合成中钴催化剂催化活性的影响。通过在多壁碳纳米管载体上的微乳液体系中浸渍钴活性相来制备钴催化剂​​。通过在微乳液体系中改变水与表面活性剂的摩尔比从 2 到 12，制备了一系列具有不同 Co 粒径的钴催化剂。X 射线衍射结果证实了含有氧化钴和金属钴的钴相的复杂组成，具有六方密堆积和面心立方相。结果表明，较大的钴颗粒表现出更多的面心立方和更少的六方密堆积金属钴。