Elucidation of reaction network and effective control of carbon number distribution in the three phase Fischer-Tropsch synthesis

作者：Liu Xiaohao; Li Xiaohong; Suehiro Yoshifumi; Fujimoto Kaoru^*

来源：Applied Catalysis A: General , 2007, 333(2): 211-218.

DOI：10.1016/j.apcata.2007.09.008

• Fischer-Tropsch synthesis
• Co/SiO(2) catalyst
• co-fed olefins
• disproportionate reaction
• chain initiation
• carbon number distribution

Reactions over olefins introduced during FT synthesis have been studied in a trickle bed reactor. Incorporation of 1-olefins into a growing alkyl chain could remarkably enhance the selectivity up to around 90% in heavy wax or middle distillate from syngas and could decrease the yields of lighter hydrocarbons with a higher CO conversion compared to the conventional FT synthesis. Results showed two significant processes the degradation of 1-olefins with successive demethylation, and its chain growth with incorporation by methylene species formed from demethylation, which is defined as the disproportionate reaction. The disproportionate reaction is competitive with introduced 1-olefins incorporating CH(2) species formed from syngas into heavier hydrocarbons and is effectively controllable; Such control strongly depends on the process conditions. In general, the elimination of diffusion limitations for introduced 1-olefins and operating conditions that give a high intrinsic chain growth probability (alpha value) are favorable for suppressing the disproportionate reaction and for promoting the chain growth by the incorporation of syngas-formed CH(2) species to increase the yields of heavier FT products.

• 出版日期2007-12-15