Enhanced Fischer-Tropsch Catalysts for Conversion of Biomass and Coal to Transportation Fuels

The United States needs viable alternatives to crude oil to moderate the effect of oil price hikes and provide an interim bridge until other fuel sources can commercially supplant petroleum-based fuels.  The candidate resources that can be used to produce liquid fuels include biomass, oil sands, oil shale and coal.  Coal is by far the largest and least expensive resource, with over 250 billion tons of known domestic reserves.  Co-gasification of coal and biomass will reduce the carbon footprint of the CBTL processes while Fischer-Tropsch (FT) synthesis is the most economically viable option to produce transportation fuels from syngas. Although the FT process is run on a commercial scale in both South Africa and Malaysia, several challenges face the production of liquid fuels from coal, including the attrition resistance of the catalyst and downstream hydrocarbon separation.  The FT process could also benefit from a highly selective catalyst to produce desired range of hydrocarbon products. 

TDA Research, Inc. (TDA) is developing a unique catalytic material to address three technical challenges: FT activity, catalyst selectivity and better heat management.  TDA’s FT catalyst will produce the desired (gasoline or diesel) range hydrocarbons (rather than producing heavy wax and then cracking it into lower molecular weight hydrocarbons). A key advantage of our approach is the reduction in the number of processing steps and process severity in the conversion of FT products into the respective transportations fuels (gasoline or diesel). In a conventional FT process, without cracker processing of the product stream, only 16% of the plant output falls into the range of a gasoline hydrocarbon cut.  Even with further processing, this production rate only increases to 26% of the plant output, with a loss of 9% of the available production during the downstream processing.  TDA’s novel size-selective FT catalyst has achieved 68% selectivity in the naphtha range in preliminary bench scale testing experiments.  Naphtha is used in gasoline blending and this cut represents the highest value product that can be produced from the FT process. The results from our FT catalyst development will be presented in the meeting.