(8b) Computational Design of Catalysts and Chemical Modeling of FTS from Syngas
AIChE Spring Meeting and Global Congress on Process Safety
2014
2014 Spring Meeting & 10th Global Congress on Process Safety
Emerging Technologies in Clean Energy for the Twenty-First Century
Fischer-Tropsch Catalysts and Reactions
Monday, March 31, 2014 - 10:30am to 11:00am
Computational Design of Catalysts and Chemical Modeling of FTS from Syngas
Suraj Gyawali, Purnima Kharidehal, Fernando Soto and Dr. Daniela Mainardi
Institute for Micromanufacturing, Chemical Engineering,
Louisiana Tech University
Fischer -Tropsch Synthesis (FTS) is a surface catalyzed polymerization reaction that synthesize hydrocarbons by hydrogenation of carbon monoxide. During the reaction, carbon monoxide is first adsorbed on the surface of the catalyst, and is hydrogenated to produce CHx monomers. These CHx monomers then propagate to form a wide product range of long chain hydrocarbons. Catalysts used in this reaction are 3-d transition metals like Cobalt, Iron, Nickel, and Ruthenium. These catalysts play an important role in product selectivity, since the products can be olefins, paraffin, and/or alcohol. Currently, FTS has gained a lot of attention in the energy industry because it is also a promising method of producing clean transport fuels with exceptionally low aromaticity and lack of sulphur content. Controlling product selectivity and overcoming catalyst deactivation has been a challenge in order to make this technology commercially available. An optimal design of a catalyst, which can make the FTS commercially viable, includes the study of CO adsorption and the reaction mechanism of FTS on the surface of the catalyst. In this work, stepped surface and alloyed nano-cluster catalysts based on Co, Fe, Ni, and Ru have been studied using electronic structure methods. Alloyed nano-cluster and stepped catalysts are attractive because they have different catalytic properties than either of the parent metals or the flat surfaces. Therefore, Density Functional Theory has been used to understand the catalytic activity in Fischer-Tropsch reaction, which includes the geometry optimization of the stepped and alloyed nano-cluster catalysts, study of CO adsorptions, CO dissociations, and the reaction mechanism on the surface of the different catalysts.