Efficient separation of xylene isomers by nonporous adaptive crystals of hybrid[3]arene in both vapor and liquid phases

Abstract

The separation of xylene isomers is a major challenge in the field of petrochemical industry. However, traditional distillation method is an energy-intensive process for the separation of xylene isomers. Herein,...

Highly Efficient Separation of BTEX via Amide Naphthotube Cavity-Confined Tandem C/N–H···π Interactions

“…Whereas DiTrip-tyQxCav and EtQxBox only afford C−H•••π interactions mainly through the upper and lower rim of the aromatic surfaces and hydrogen bonding interactions in the medium rim, resulting in relatively weak synergistic interactions that are not conducive to the complete separation of BTEX. Similarly, hybrid [3]arene 32…”

“…Whereas DiTriptyQxCav and EtQxBox only afford C–H···π interactions mainly through the upper and lower rim of the aromatic surfaces and hydrogen bonding interactions in the medium rim, resulting in relatively weak synergistic interactions that are not conducive to the complete separation of BTEX. Similarly, hybrid[3]arene can only achieve separation of o -xylene in xylene isomers driven by C–H···O and C–H···π interactions within the channel of the host, due to the inappropriate cavity size of hybrid[3]arene, which makes the guest incapable of entering the cavity of hybrid[3]arene to form more host–guest interactions to achieve the complete separation of xylene.…”

“…31 hybrid [3]arene, which exhibited high selectivity for o-xylene from the mixture of xylene isomers in both vapor and liquid phases. 32 The high selectivity of hybrid [3]arene was attributed to multiple C−H 34 These works suggest that rationally designed supramolecular structures have the potential to further improve BTEX separation via multiple noncovalent interactions and afford inspiration for the design of novel supramolecular separation materials. Naphthotubes, as a novel class of endo-functionalized supramolecular hosts with unique hydrophobic cavities containing polar binding sites, have been gradually used in molecular recognition, 35−39 self-assembly, 45 and sensing.…”

“…Nonetheless, the success of these endeavors relies on the C–H···π or π–π interactions between the host and guest, which unfortunately are not sufficient to achieve complete separation of xylene isomers. Zhou and co-workers reported a supramolecular-hybrid[3]arene, which exhibited high selectivity for o -xylene from the mixture of xylene isomers in both vapor and liquid phases . The high selectivity of hybrid[3]arene was attributed to multiple C–H···O and C–H···π interactions between hybrid[3]arene and o -xylene.…”