Modeling of Fischer-Tropsch synthesis

Abstract

The standard model for the growth and termination of hydrocarbon chains in the Fischer‐Tropsch (FT) reaction is based on a classical polymer kinetic theory due to Flory. Unfortunately, the Flory model predicts a low liquid product yield. Although the weight distributions of hydrocarbon products observed with most Fischer‐Tropsch catalysts do, in fact, fit a Flory distribution, to accept the Flory model as the definitive model for hydrocarbon production is to admit that little can be done to improve the liquid product yield. Consequently, we have postulated additional chemical processes, which could conceivably occur in FT synthesis, and we have theoretically determined the effect of these processes on the weight distribution of products. Certain processes resulted in a dramatic increase in the liquid product selectivity— as much as 2‐3 times the selectivity predicted by the Flory model. Thus, if catalysts can be tailored so as to include these chemical processes, such catalysts could dramatically increase the liquid product yield as compared to ordinary FT catalysts.