Iron catalyst for ammonia synthesis doped with lithium oxide
Iron catalysts doped with Al2O3, CaO were obtained by melting iron oxide with 2.2 wt.% of Al2O3, 2.1 wt.% of CaO. The reduced catalyst was impregnated with lithium hydroxide water solution. Activity measurements were carried out in the laboratory installation in the temperature range 623–773 K under the pressure of 10 MPa. The activity of catalyst containing 0.79 wt.% of Li2O and reduced at 773 K was similar to the activity of an industrial iron catalyst doped with potassium oxide. After reduction at 923 K the catalyst containing 0.48 wt.% of Li2O was about 15% more active than the industrial catalyst. Increasing Li2O concentration results in the decrease of the surface area of a catalyst reduced at 923 K. The most active catalysts doped with lithium oxide were more active than the industrial catalyst when their activity was calculated and scaled down to surface area units.
Journal: Catalysis Communications - Volume 10, Issue 14, 25 August 2009, Pages 1821–1823