Effect of potassium on GO-modified large Fe3O4 microspheres for the production of α-olefins

Abstract

Despite that iron-based catalysts are preferred for the high selectivity to value-added α-olefins via Fischer-Tropsch synthesis (FTS) reaction, the carbon deposition leads to deactivate catalyst more readily and CO2 selectivity as high as ~50% leads to low carbon efficiency. Herein, we developed an innovative approach to fabricate iron-based catalysts to deal with this issue. In detail, prepare Fe3O4 microsphere with an average particle size of ~580 nm via hydrothermal method and mix it with GO. The GO modification could effectively inhibit the sintering and coking of the large Fe3O4 microspheres (580 nm) by assisting its evolution into much smaller iron carbide nanocapsules (~9.1 nm). And the obtained catalyst exhibited excellent reaction activity, stability and high α-olefin selectivity. The addition of K into Fe3O4 microsphere produces major ɛ’-Fe2.2C about 58.9% in the evolution process and facilitates lower CO2 emission obviously.