Combined Adsorption and Reaction in the Ternary Mixture N₂, N₂O₄, NO₂ on MIL-127 Examined by Computer Simulations

Abstract

A high selectivity of NO x over N2 (simulating air) is found in silico when studying the adsorption of the ternary mixture N2O4/NO2/N2 on the metal–organic framework MIL-127­(Fe) by molecular simulations under consideration of the recombination reaction N2O4 ↔ 2NO2. The number of N atoms in nitrogen oxides NO x and that in N2 is used to define a selectivity of the combined adsorption and chemical recombination that can reach values of about 1000.

Adsorption and the Chemical Reaction N2O4 ↔ 2NO2 in the Presence of N2 in a Gas Phase Connected with a Carbon Nanotube

“…It was sufficient to consider only NO 2 because at 374 K, the NO x exist almost entirely as NO 2 . The chemical reaction is described and discussed in more detail in the Supporting Material of Fritzsche et al…”

“…Adsorption of NO x on porous materials for separation purposes has been examined in several papers, − which are discussed in more detail in ref . Taking reaction into account should improve the accuracy of the results.…”

“…However, in ref , only the NO x without the presence of other gases have been considered. The interesting question of use of this type of adsorption and reaction for the separation of both NO 2 and N 2 O 4 from air (or from N 2 , respectively) under the consideration of the chemical reaction (reaction ) has only been investigated in ref . Fritzsche et al used the Gibbs ensemble Monte Carlo (GEMC) and RxMC simulations to investigate the adsorption and reaction of a ternary mixture, N 2 O 4 /NO 2 /N 2 , on the MOF material MIL-127.…”

“…The interesting question of use of this type of adsorption and reaction for the separation of both NO 2 and N 2 O 4 from air (or from N 2 , respectively) under the consideration of the chemical reaction (reaction ) has only been investigated in ref . Fritzsche et al used the Gibbs ensemble Monte Carlo (GEMC) and RxMC simulations to investigate the adsorption and reaction of a ternary mixture, N 2 O 4 /NO 2 /N 2 , on the MOF material MIL-127. To characterize the selectivity between the total amount of NO x and that of N 2 , the ratio of N atoms in all NO x molecules (N 2 O 4 + NO 2 ) to N atoms in N 2 in the gas phase, or in the adsorbed phase, respectively, has been used in ref to treat the ternary mixture like a binary mixture.…”

“…Fritzsche et al used the Gibbs ensemble Monte Carlo (GEMC) and RxMC simulations to investigate the adsorption and reaction of a ternary mixture, N 2 O 4 /NO 2 /N 2 , on the MOF material MIL-127. To characterize the selectivity between the total amount of NO x and that of N 2 , the ratio of N atoms in all NO x molecules (N 2 O 4 + NO 2 ) to N atoms in N 2 in the gas phase, or in the adsorbed phase, respectively, has been used in ref to treat the ternary mixture like a binary mixture. We will also do that in the present paper for two reasons.…”