Modelling of N2O/NO Separation in Acid Mordenite: Comparison with Gas-Chromatographic Experiments

Molecular modelling, utilising the Grand Canonical Monte Carlo method, was employed to study the interactions between nitrous oxide (N2O) and nitric oxide (NO) with a solid matrix, namely mordenite, before and after charge equilibration. The results indicate that the charge equilibration leads to an adsorption which is independent of the pressure. Comparison with gas-chromatographic experiments indicate that charge equilibration is not allowed in acid mordenite. Therefore, in the case of polar molecules, their adsorption depends on the charge in the zeolite micropores. Furthermore, molecular modelling can be utilised to also predict gas-solid-chromatographic separations, provided that calculations take into account the presence of the carrier gas to obtain an approach of calculated separation factors similar to those found experimentally.