(705f) Increasing Liquid Fuels Selectivity in Fisher-Tropsch Synthesis From CO2-Rich Syngas

Wang, L., North Carolina Agricultural and Technical State University
Shahbazi, A., North Carolina Agricultural and Technical State University

Fischer-Tropsch (FT) synthesis is a classic polymerization reaction in which a mixture of hydrogen and carbon monoxide (syngas) is converted to hydrocarbons and liquid fuels in presence of a metallic catalyst. FT synthesis could be considered as a promising technology to produce clean liquid fuels since it is able to match with different feedstocks including coal, natural gas, and biomass. While natural gas- and coal-based FT plants have already become a matured technology and been operated around the world, biomass-based plants are still under study and development. The ideal H2/CO ratio of syngas entering a FT reactor is about 2.1. However, this ratio for the syngas derived from a biomass gasification reactor is often around 1. Such syngas usually contains significant amount of CO2. Typical FT catalysts and processes cannot efficiently utilize CO2. In this study, we have examined the possibility of utilizing CO2 in two different feedstock: CO2/H2 and CO2/CO/H2. Performance and hydrocarbon distribution of different cobalt and iron based FT catalysts have been examined under a variety of FT synthesis conditions to study the effects of CO2 presence in syngas feedstock on the efficiency and selectivity of a FT process and possible conditions for utilizing CO2 in hydrocarbon production.