1 research outputs found
Conversion of CO<sub>2</sub>, CO, and H<sub>2</sub> in CO<sub>2</sub> Hydrogenation to Fungible Liquid Fuels on Fe-Based Catalysts
CO<sub>2</sub> hydrogenation conducted on Fe-based catalysts consists
of a wide range of reactions with CO<sub>2</sub> and H<sub>2</sub> reacting in the reverse water–gas shift (RWGS) to produce
CO and CO and H<sub>2</sub> reacting in the Fischer–Tropsch
(FT) type reactions leading to hydrocarbons and oxygenates. Methanation
and Boudouard side reactions are extremely detrimental to selectivity
and stability of the Fe-based catalysts. The catalytic system is very
complex, posing challenging issues that require fundamental understanding
of the dynamics of changes in the catalytic phases, mechanism of key
reactions, and effects of catalyst composition including key promoters.
A comprehensive analysis of fundamental aspects of catalytic materials,
phases, and promoters and the catalytic mechanisms are presented in
this paper. It was established that the ratio of Fe<sub>carbide</sub>/Fe<sub>oxide</sub> atoms at the surface of an activated catalyst
responsible for its selectivity is determined by the environment of
iron ions in oxide precursors changed by insertion of ions of other
metals. Fungible liquid fuels were produced in bench scale reactors
and demonstrated to be suitable as blending stock for transportation
fuels. The techno-economic analysis of processes using CO<sub>2</sub> and either water, biogas, or natural gas as feedstock was conducted.
As expected, the production of eco-friendly, renewable fuels based
on CO<sub>2</sub> is not competitive with fuels based on crude oil
because of the high cost of production of hydrogen