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Separation of p‐xylene (kinetic diameter ca. 0.58 nm) from its bulkier isomers (o‐xylene and m‐xylene, ca. 0.68 nm) is challenging, but important in the petrochemical industry. Herein, we developed a highly selective and stable metal–organic framework (MOF) MIL‐160 membrane for selective separation of p‐xylene from its isomers by pervaporation. The suitable pore size (0.5∼0.6 nm) of the MIL‐160 membrane selectively allows p‐xylene to pass through, while excluding the bulkier o‐xylene and m‐xylene. For the separation of equimolar binary p‐/o‐xylene mixtures at 75 °C, high p‐xylene flux of 467 g m−2 h−1 and p‐/o‐xylene selectivity of 38.5 could be achieved. The stability of MIL‐160, ensured the separation performance of the MIL‐160 membrane was unchanged over a 24 h measurement. The high separation performance combined with its high thermal and chemical stability makes the MIL‐160 membrane a promising candidate for the separation of xylene isomers.

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The hydrogenation of sequestrated CO 2 to methanol can reduce CO 2 emission and establish as ustainable carbon circuit. However,t he transformation of CO 2 into methanol is challenging because of the thermodynamic equilibrium limitation and the deactivation of catalysts by water.Inthe present work, different reactor types have been evaluated for CO 2 catalytic hydrogenation to methanol. Best results have been obtained in abifunctional catalytic membrane reactor (CMR) based on az eolite LTAm embrane and ac atalytic Cu-ZnO-Al 2 O 3 -ZrO 2 layer on top.Due to the in situ and rapid removal of the produced water from the catalytic layer through the hydrophilic zeoliteL TA membrane,itiseffective to break the thermodynamic equilibrium limitation, thus significantly increasing the CO 2 conversion (36.1 %) and methanol selectivity (100 %). Further,t he catalyst deactivation by the produced water can be effectively inhibited, thus maintaining ahigh longterm activity of the CMR.

Covalent-organic frameworks (COFs) are ordered crystalline materials covalently formed by building blocks of light elements. There has been increasing interest in the development of COF membranes for chemical separation. In this study, seven two-dimensional (2D) COF membranes are computationally designed with different functional groups and aperture sizes. By 245 sets of molecular simulations, the seven ultrathin COF membranes are investigated for organic solvent nanofiltration (OSN) of seven solvents (acetonitrile, acetone, methanol, ethanol, isopropyl alcohol, methyl ethyl ketone, and n-hexane) and four solutes (2,5-furandiamine, paracetamol, α-methylstyrene dimer, and Nile red). The solvent fluxes through the COF membranes are revealed to be governed by the aperture size and membrane functionality, as well as solvent properties. In general, the larger the aperture size, the higher is the flux. For membranes with comparable aperture size, the hydrophobic one exhibits higher fluxes than the hydrophilic counterpart for all the solvents except n-hexane. To elucidate this trend, solvent structures near the membranes are analyzed and the potentials of mean force for solvent permeation are evaluated. The solvent permeances through hydrophobic and hydrophilic membranes are correlated respectively with two different combinations of solvent properties. The solute rejection is found to depend on a complex interplay among solute size and polarity, solvent viscosity, solute–solvent interaction, aperture size and membrane functionality. In the presence of solutes, solvent permeances are reduced by approximately 10%. From the bottom-up, this comprehensive computational study provides quantitative insights into solvent permeation and solute rejection in the COF membranes, unravels the key governing factors, and would facilitate the development of new membranes for high-performance OSN.