TY - JOUR
T1 - The effect of cations on the ammonia synthesis reaction under the confinement in FAU zeolites
AU - Zhakisheva, Botagoz
AU - Gutiérrez-Sevillano, Juan José
AU - Calero, Sofia
N1 - Publisher Copyright:
© 2024 The Authors
PY - 2025/3/1
Y1 - 2025/3/1
N2 - We performed Monte Carlo molecular simulations in RMC and GCMC ensembles, to study the impact of Na+ charge-balancing cations in the aluminum-substituted zeolites on the adsorption behavior of H2, N2, and NH3. The adsorption isotherms were obtained for single-component gas adsorption and adsorption from the ammonia synthesis reaction mixture. Our findings indicate that the presence of Na+ cations in zeolites alters the adsorptive characteristics of all the molecules under the study. Specifically, Na+ cations have a significant influence on the adsorption behavior of ammonia, effectively preventing its phase transition. Adsorption from the mixture showed that Na + cations enhanced the selectivity of ammonia adsorption over N2, and H2, as compared to pure-silica zeolites. Further, the impact of cations on the reaction equilibrium under the confinement of FAU zeolite was investigated. The confinement effect in ammonia production was shown to be improved due to the presence of cations. We suggest that the optimal conditions for the process can be reached at 573 K and 10 bar, providing a good value of 0.93 of ammonia mole fraction adsorbed.
AB - We performed Monte Carlo molecular simulations in RMC and GCMC ensembles, to study the impact of Na+ charge-balancing cations in the aluminum-substituted zeolites on the adsorption behavior of H2, N2, and NH3. The adsorption isotherms were obtained for single-component gas adsorption and adsorption from the ammonia synthesis reaction mixture. Our findings indicate that the presence of Na+ cations in zeolites alters the adsorptive characteristics of all the molecules under the study. Specifically, Na+ cations have a significant influence on the adsorption behavior of ammonia, effectively preventing its phase transition. Adsorption from the mixture showed that Na + cations enhanced the selectivity of ammonia adsorption over N2, and H2, as compared to pure-silica zeolites. Further, the impact of cations on the reaction equilibrium under the confinement of FAU zeolite was investigated. The confinement effect in ammonia production was shown to be improved due to the presence of cations. We suggest that the optimal conditions for the process can be reached at 573 K and 10 bar, providing a good value of 0.93 of ammonia mole fraction adsorbed.
UR - http://www.scopus.com/inward/record.url?scp=85213230002&partnerID=8YFLogxK
U2 - 10.1016/j.micromeso.2024.113480
DO - 10.1016/j.micromeso.2024.113480
M3 - Article
AN - SCOPUS:85213230002
SN - 1387-1811
VL - 385
JO - Microporous and Mesoporous Materials
JF - Microporous and Mesoporous Materials
M1 - 113480
ER -