110th Anniversary: Fischer-Tropsch Synthesis for Multiphase Product Recovery through Reactive Distillation

The Fischer-Tropsch (FT) reaction is an important bridge between inorganic synthesis gas and transportation fuels such as diesel and gasoline. It is receiving even more attention today as a technology to produce transportation fuels from shale/natural gas, coal, biomass, and also from stranded gas produced from remote oil fields. Reactive distillation (RD) is a proven reactive separation method that can save downstream separation costs by performing separation and reaction simultaneously. In addition, it can enhance yield by constantly removing byproducts and thus create favorable zones for equilibrium restricted reactions. It can also enhance conversion by increasing reactant concentration through enhanced gas phase feed solubility in the liquid phase. In this work, we build a rigorous mathematical model to simulate and optimize an FT RD column, with enhanced formulation to handle disappearing phases and optimal tray counts, feed points, and product draws. The design is optimized with an economic objective that favors the production of gasoline. The optimization results indicate that reactive distillation can offer much better performance than a baseline slurry phase reactive flash, both in terms of conversion and selectivity.