Abstract
Industrially, ammonia is generated mainly using the energy-intensive and CO2-emitting Haber-Bosch process, which is not conducive to sustainable economic and social development. The chemical looping ammonia synthesis (CLAS) is capable of coupling green energy, which is one of the available alternatives to the Haber-Bosch process, but the ammonia production rate of most of its nitrogen carriers is unsatisfactory. In this work, we designed a self-assembled nitrogen carrier using ZSM-5 molecular sieve (ZSM-5) and nickel (Ni) to modify chromium nitride (CrN). ZSM-5 molecular sieves have a rich pore structure, which enables the gas-phase reactants to react with the lattice nitrogen in the subsurface layer of the nitrogen carrier. Nickel can facilitate the dissociation of hydrogen during hydrogenation due to its higher hydrogen affinity. The ammonia production rate of the nitrogen carrier can reach 451.2 μmol g−1 h−1 at 700 °C and atmospheric pressure, and be able to remain 358 μmol g−1 h−1 after eight cycles. Furthermore, we also propose a full-coverage design strategy for nitrogen carriers: simultaneous optimization of the chemical and mass transfer processes in the nitrogen carrier. This work advances the design of high-performance nitrogen carrier, thus facilitating the applications of CLAS for the distributed ammonia synthesis.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call