Health & Environmental Research Online (HERO)


Print Feedback Export to File
7754180 
Journal Article 
Reaction behavior of Fischer-Tropsch synthesis in near critical and supercritical hexane media 
Huang, XW; Roberts, CB 
2002 
0 
Abstracts of Papers of the American Chemical Society
ISSN: 0065-7727 
AMER CHEMICAL SOC 
Orlando, FL 
224th ACS National Meeting 
223 
1 
U573-U573 
English 
WOS:000176296703146 
The Fischer-Tropsch (FT) reaction under supercritical hexane conditions in a continuous, high pressure, fix-bed reactor by employing a cobalt catalyst (15%Co-0.5%Pt-Al2O3) were investigated. The effect of supercritical fluid (SCF) conditions on synthesis gas conversion, product distribution and olefin selectivity was presented in order to demonstrate improvements in process parameters under SCF-FT operation versus gas phase operation. The effects of isothermal pressure-tuning on the catalyst activity, product distribution, and olefin selectivity were studied. In the near critical and supercritical region, optimal combinations of product desorption and pore transport were obtained. The synthesis gas space velocity was varied to determine whether the primary and/or secondary reaction steps were diffusion controlled. Due to the increased diffusion and desorption rate of reactants and products in SCF phase FT synthesis, the CO conversion and olefin content were higher than that in conventional FTS. Higher selectivity of the olefin products suggested that the SCF-FT operation results in higher pore diffusivities and more rapid removal of heavy 1-olefins from catalyst, thereby suppressing secondary hydrogenation and isomerization reactions.