Effect of the Number of Methyl Groups in DMOF on N 2 O Adsorption and N 2 O/N 2 Separation.

Nitrous oxide (N 2 O), as the third largest greenhouse gas in the world, also has great applications in industry, so the purification of N 2 O from N 2 in industrial tail gas is a crucial process for achieving environmental protection and giving full play to its economic value. Based on the polarity difference of N 2 O and N 2 , N 2 O adsorption was researched on DMOF series materials with different polarities and methyl numbers of the ligand. N 2 O adsorption at 0.1 bar is enhanced, attributed to an increase of the methyl group densities at the benzenedicarboxylate linker. Grand canonical Monte Carlo simulations demonstrate the key role of methyl groups within the pore surface in the preferential N 2 O affinity. Methyl groups preferentially bind to N 2 O and thus enhanced low (partial) pressure N 2 O adsorption and N 2 O/N 2 separation. The result shows that DMOF-TM has the highest N 2 O adsorption capacity (19.6 cm 3 /g) and N 2 O/N 2 selectivity (23.2) at 0.1 bar. Breakthrough experiments show that, with an increase of the methyl number, the coadsorption time and retention time also increase, and DMOF-TM has the best N 2 O/N 2 separation performance.