Modelling ammonia and nitrous oxide decomposition reactions in solid oxide fuel cells for combined energy generation and treatment of flue gas streams.

Solid oxide fuel cells (SOFCs) offer a promising technology for clean and efficient power generation. In this study, an SOFC combining in-situ hydrogen generation from ammonia with nitrous oxide reduction to nitrogen was simulated and validated against experimental results for the first time. Ammonia decomposition generates the hydrogen needed for the electroreduction of nitrous oxide, with simultaneous generation of electrical power. Nickel was considered as the anode catalyst since it is highly active for ammonia decomposition. Perovskite catalyst LSCF - lanthanum strontium cobalt ferrite, was used as the cathode where N 2 O, a potent greenhouse gas, is efficiently decomposed into harmless molecular nitrogen and oxygen. The simulation study was performed on ANSYS Fluent, a CFD platform. The developed simulator was revealed to be a powerful tool to understand and optimize the operating conditions of the reactor, when applied to the treatment of the flue gas of a nitric acid plant. Under optimal conditions, the modelled reactor displays current densities >100 mA·cm−2 and power densities of ca. 11 mW·cm−2, where full conversion of N 2 O could be obtained by adjustments of the residence time. Besides nitric acid plants, these findings provide valuable insights for further industries with N 2 O emissions and those involved in the delivery and storage of ammonia, ultimately contributing to the advancement of SOFC as an effective integrated technology for combined electrical generation and flue gas stream treatment. The development of new SOFCs enables the valorisation of potent greenhouse gases such as N 2 O and sustainable power generation. • First-ever report of a Solid Oxide Fuel Cell (SOFC) to eliminate N 2 O emissions while generating power from ammonia. • Successful development and validation of a Computational Fluid Dynamics model for the SOFC. • High current densities (>100 mA⋅cm-2) and power densities (11 mW⋅cm-2) reached at optimal conditions. • Demonstrated the potential for industrial application reducing N 2 O from the Ostwald process tail gas by 99%. [ABSTRACT FROM AUTHOR]