Hydrocarbon synthesis from CO2 over Fe–Cu catalysts

Hydrocarbons and carbon monoxide were produced from carbon dioxide and hydrogen at 400°C over copper-promoted iron catalysts containing sodium. The major surface phases of the catalysts were FeO and/or FeCO₃ although iron carbide is believed as an active phase of the hydrocarbon synthesis from carbon monoxide. Copper was present as metal on the surface and the surface density was considerably high even if the content of copper was less than 1 wt%. The surface density of sodium was not negligible in the catalysts containing sodium less than 0.1 wt% and the sodium ion can affect the surface basicity of the catalysts. The olefin content in the products is believed to relate to the surface basicity.