Membranes with Nanochannels Based on Pillar[6]arenes to Separate Xylenes

Abstract

Membrane separation technology has been widely applied in material separation fields. However, it still has the disadvantage of poor selectivity at nanometer and sub-nanometer scales. Here, two kinds of pillar[6]arene with opposite charges were prepared by modification, and the aligned nanochannel composite membrane was successfully constructed by directional assembly on a negatively charged silicon interface. The precise sieving properties of aligned channels were studied using the xylene isomer as a model molecule. It has been proved that the aligned channel can better maintain the pore size close to the macrocyclic molecules, which is beneficial to realize the customized construction of the through-ordered nanochannel. The experimental results show that the aligned nanochannel can selectively transport xylene isomers, and the flux (J) values of o, m, and p-xylene were 9.2, 11.6, and 171.3 nM m–2 h–1, respectively. Finally, the separation and purification of mixed samples have been achieved. This method provides a strategy for constructing ordered nanochannels.

Highly Selective p-Xylene Separation from Mixtures of C8 Aromatics by a Nonporous Molecular Apohost

“…In previous work, sorbents that exhibit discrimination for PX, typically adapt to the size and shape of PX molecules, controlling their pore structure via a gating mechanism, leading to a guest-loaded complex with the lowest binding energy and preference for PX over other C8 aromatic isomers. ,, PX clathrate TPBD-PX offers precise size/shape matching to accommodate PX molecules, establishing favorable positions for C–H···π interactions along the a -axis. CH···O and CH···N interactions formed between the host and guest serve to anchor the PX molecules.…”

“…The crystallization energies, i.e., −78.8 (PX), −67.8 (MX), −61.9 (OX), and −65.6 (EB) kJ/mol, are indicative of strongly exothermic crystallization processes and show a strong preference to enclathrate PX over the other C8 aromatic isomers (see Table S11 In previous work, sorbents that exhibit discrimination for PX, typically adapt to the size and shape of PX molecules, controlling their pore structure via a gating mechanism, leading to a guest-loaded complex with the lowest binding energy and preference for PX over other C8 aromatic isomers. 19,20,77…”

A Visible‐Light Regulated ATP Transport in Retinal‐Modified Pillar[6]arene Layer‐by‐Layer Self‐Assembled Sub‐Nanochannel

“…Next, 10 % PMMA (polymethyl methacrylate) of chlorobenzene solution was spined on the surface of the retinal modified pillar[6]arene assemble channels. Then, the dried PMMA fixed surface was immersed into the 2 % HF aqueous solution to obtain the self‐supporting membrane [46] . The membrane of the retinal modified pillar[6]arene channel is colorless and transparent, with a diameter of approximately 25 mm.…”

Enhanced polarization via Joule heating in wood-derived carbon materials for absorption-dominated EMI shielding

“…The saturated temperature could reach 55.5 1C, 80.5 1C, 90.0 1C and 65.5 1C at 2.5 V, respectively, surpassing those of some representative shielding materials reported in the literature. [54][55][56] Furthermore, the samples remained stable with only a 4.2 wt% weight loss when exposed to a temperature of 90 1C for 50 minutes (Fig. S22, ESI †).…”