Patent ID: 7183327

Claim:
A method for producing hydrocarbons from synthesis gas in a slurry bubble reactor, the slurry bubble reactor including a liquid and a catalyst at conversion promoting conditions, wherein the liquid has a density, ρ L , and viscosity, μ L under said conversion promoting conditions and wherein the catalyst comprises a plurality of catalyst particles including fresh catalyst particles, the fresh catalyst particles having a particle density, ρ P , and particle sizes, d P , the method comprising the steps of: (a) selecting the fresh catalyst particles such that the fresh catalyst particles have Archimedes numbers between about 0.02 and about 250, the Archimedes numbers being defined by Ar=gd P 3 ρ L (ρ P −ρ L )/μ L 2 ; and (b) passing a synthesis gas feed stream in said slurry bubble reactor over said catalyst under said conversion promoting conditions to convert at least a portion of said synthesis gas feed stream to hydrocarbons.