1 research outputs found
Promoted Iron Nanocrystals Obtained via Ligand Exchange as Active and Selective Catalysts for Synthesis Gas Conversion
Colloidal
synthesis routes have been recently used to fabricate
heterogeneous catalysts with more controllable and homogeneous properties.
Herein a method was developed to modify the surface composition of
colloidal nanocrystal catalysts and to purposely introduce specific
atoms via ligands and change the catalyst reactivity. Organic ligands
adsorbed on the surface of iron oxide catalysts were exchanged with
inorganic species such as Na<sub>2</sub>S, not only to provide an
active surface but also to introduce controlled amounts of Na and
S acting as promoters for the catalytic process. The catalyst composition
was optimized for the Fischer–Tropsch direct conversion of
synthesis gas into lower olefins. At industrially relevant conditions,
these nanocrystal-based catalysts with controlled composition were
more active, selective, and stable than catalysts with similar composition
but synthesized using conventional methods, possibly due to their
homogeneity of properties and synergic interaction of iron and promoters