Design, Synthesis, and Mechanistic Evaluation of Iron-Based Catalysis for Synthesis Gas Conversion to Fuels and Chemicals

Iglesia, Enrique

University of California

关键词: Removal;    Hydrocarbons;    Biomass;    Synthesis Gas;    Transport;   

DOI  :  10.2172/875336
RP-ID  :  none
RP-ID  :  FC26-03NT41964
RP-ID  :  875336

美国|英语

来源: UNT Digital Library

【 摘 要 】

This project explores the extension of previously discovered Fe-based catalysts with unprecedented Fischer-Tropsch synthesis rate, selectivity, and ability to convert hydrogen-poor synthesis gas streams typical of those produced from coal and biomass sources. Contract negotiations were completed on December 9, 2004. During the first reporting period, we certified a microreactor, installed required analytical equipment, and reproduced synthetic protocols and catalytic performance previously reported. During this second reporting period, we have prepared and tested several Fe-based compositions for Fischer-Tropsch synthesis and tested the effects of product recycle under both subcritical and supercritical conditions. These studies established modest improvements in rates and selectivities with light hydrocarbon recycle without any observed deleterious effects, opening up the opportunities for using of recycle strategies to control temperature profiles in fixed-bed Fe-based Fischer-Tropsch synthesis reactors without any detectable kinetic detriment. In a parallel study, we examined similar effects of recycle for cobalt-based catalysts; marked selectivity improvements were observed as a result of the removal of significant transport restrictions on these catalysts. Finally, we have re-examined some previously unanalyzed data dealing with the mechanism of the Fischer-Tropsch synthesis, specifically kinetic isotope effects on the rate and selectivity of chain growth reactions on Fe-based catalysts.