The Origin of p-Xylene Selectivity in a DABCO Pillar-Layered Metal–Organic Framework: A Combined Experimental and Computational Investigation

Abstract

We report high experimental p-xylene (pX) selectivity in a pillar-layered metal−organic framework, DUT-8(Cu). Vapor-and liquid-phase adsorption experiments were carried out to confirm high pX selectivity and large pX uptakes in . Grand canonical Monte Carlo simulation results show that the presence of DABCO ligands allows for the packing of pX molecules and is responsible for the pX selective nature of the material. The simulation also suggests that the presence of isooctane solvents in the liquid-phase experiments plays an essential role by lowering the adsorption of other xylene isomers, and leads to increased pX selectivity in the liquid-phase as compared to the vapor phase. Density functional theory simulations show that the preferential arrangement is due to the preferential adsorption of pX on the DABCO ligand and the preferential adsorption of isooctane over other xylene isomers.

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“…By combining experimental and simulation techniques, we investigated xylene separation by a highly selective and stable MIL-160 membrane with a suitable pore size (0.5–0.6 nm), which could selectively allow p -xylene to pass through while excluding o -xylene and m -xylene . From simulation, Kim et al explored the origin of highly selective adsorption of p -xylene in a DABCO pillar-layered MOF, which was attributed to the preferential packing of p -xylene on the DABCO ligand …”

Kerogen Swelling in Light Hydrocarbon Gases and Liquids and Validity of Schroeder’s Paradox

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Breathing‐Assisted Selective Adsorption of C8 Alkyl Aromatics in Zn‐Based Metal‐Organic Frameworks

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