25 Effects of mass transfer on Fischer-Tropsch synthesis in slurry reactors

Abstract

The heterogeneous catalytic hydrogenation of carbon monoxide to aliphatic paraffins and alpha-olefins (Fischer-Tropsch synthesis) is of particular interest as a route for conversion of carbonaceous sources to liquid hydrocarbons in that any source of carbon may be used. A slurry-bed reactor for the Fischer-Tropsch synthesis offers several advantages over alternative modes of operation. In particular, it eliminates hot spot formation that plagues fixed-bed operation and catalyst agglomeration from heavy wax condensation that troubles fluid-bed reactors. The rate and selectivity of the liquid-phase reaction may, however, be markedly affected by mass-transfer limitations, the most important of which appears to be transport of the synthesis gas from gas bubbles to the liquid. The previously published studies of the Fischer-Tropsch synthesis in a slurry reactor have been examined and, where possible, were analyzed to determine the extent to which they were affected by mass transfer.