Concentration profile of reactants in Fe catalysts for slurry Fischer-Tropsch synthesis

In order to eliminate the effect of intraparticle diffusion on reaction, catalysts of micro-meter level are used for slurry Fischer-Tropsch synthesis. But overfine catalyst size will be cumbersome to the separation of catalysts from the slurry. Size of a catalyst particle should therefore be not only able to eliminate intraparticle diffusion, but also advantageous for separation of solid from liquid. If the concentration profiles of reactants in catalysts of different size are obtained, suitable catalyst size can be determined. However, it is very difficult to measure the concentration profile in catalysts under reaction conditions. In this presentation, based on the consumption rate expressions of both H{sub 2} and CO obtained from the intrinsic Fischer-Tropsch data measured in a stirred slurry autoclave and the reaction and diffusion of a reactant within a catalyst pore, the concentration profile of reactants in catalyst particles is calculated. It provides useful information for determination of suitable catalyst size. The consumption rate of H{sub 2} and CO were measured in a 500 ml stirred slurry autoclave. Ten grams of unsupported precipitated Fe-Cu-K catalysts were prepared in a continuous precipitation reactor. Catalyst size is less than 40 mm. The experimental setup and method can be found inmore » the literature. A table gives the results under different reaction conditions. The consumption rates of H{sub 2} and CO were calculated.« less