Metal–Organic Frameworks for Highly Selective Separation of Xylene Isomers and Single-Crystal X-ray Study of Aromatic Guest–Host Inclusion Compounds

Separation of hydrocarbon molecules, such as benzene/cyclohexane and o-xylene/m-xylene/p-xylene, is relevant due to their widespread application chemical feedstock but challenging because similar boiling points close molecular sizes. Physisorption separation could offer an energy-efficient solution this problem, the design synthesis sorbents that exhibit high selectivity for one hydrocarbons remain a largely unmet challenge. Herein, we report new heterometallic MOF with unique tortuous shape channels decorated aromatic sorption sites [Li2Zn2(bpy)(ndc)3] (NIIC-30(Ph), bpy = 4,4'-bipyridine, ndc2- naphthalene-1,4-dicarboxylate) study its xylene vapor liquid separation. For equimolar mixture, it possible achieve 10-fold excess benzene in adsorbed phase. In case xylenes, microporous framework NIIC-30(Ph) demonstrates outstanding selective properties becomes benchmark m-/o-xylene addition, stable enough carry out at least three cycles mixtures or ternary o-xylene/m-xylene/p-xylene both Insights into performance are gained from X-ray structural studies each guest inclusion compound.