-With 𝜆 = 10 or 𝜆 = 1000, the productivity is more than quadrupled to 107 µmol s -1 gcat -1 at near full conversion. Additionally, the pressure can be reduced to 80 bar (𝜆 = 10) or even to 20 bar (𝜆 = 1000), and the temperature can be reduced to 400 °C at 𝜆 = 1000 as well. The conversion gain between the conventional NH3 synthesis and SEAS with 𝜆 = 2 observed here lies between 43 % (400 °C, 20 bar, 45000 h -1 ) and even 550 % (350 °C, 100 bar, 15000 h -1 ). Hence, almost full conversion per pass becomes feasible with reasonable amounts of sorbent. The maximum NH3 productivity is limited by the reactant gas flow, i.e., the GHSV.