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[Display omitted] • The insertion of pillar ligands of UPC-190 series MOFs can lead to changes in the interpenetrating structure. The degree of interpenetration can be managed by introducing different pillars. • Theoretical calculations demonstrate that the fluorine atom on pillar ligands is an effective interaction site for C 2 H 2 molecules. This means that fluorine atoms can act as active sites that interact with C 2 H 2 molecules, thereby influencing their adsorption behavior. • The formation of interpenetrating structures and the stepwise fluorination strategy gradually improve the IAST selectivity and C 2 H 2 uptake of the sample. This strategy proves guidance for designing MOFs for challenging gas separations. The efficient separation of C 2 H 2 /CO 2 possesses great commercial and research value and remains challenging due to their similar molecular sizes and physical properties. Functionalization is a powerful strategy for precisely regulating the pore environment of porous adsorbents, notably metal–organic frameworks (MOFs), for recognizing target molecules. Here, we construct three interpenetrated MOFs using a stepwise fluorinated pillar-ligand strategy. Interestingly, the degree of interpenetration can be managed by introducing different pillars. The unique interpenetrating structure cooperates with fluorine-rich pore environment significantly improves the C 2 H 2 uptake and the C 2 H 2 /CO 2 separation selectivity. The optimized difluorine-functionalized UPC-193 exhibits the highest C 2 H 2 adsorption capacity (80.45 cm3/g) and separation efficiency (C 2 H 2 /CO 2 uptake ratio of 1.9) among UPC-190 systems at ambient conditions. Ideal adsorbed solution theory (IAST) calculations, molecular modeling studies, and breakthrough experiments comprehensively demonstrate that UPC-193 is an effective MOF adsorbent for equimolar C 2 H 2 /CO 2 separation. The stepwise pillar-ligand fluorination strategy proves to be an effective approach to extend the functionality of MOFs for challenging gas separations. [ABSTRACT FROM AUTHOR]

• Pros and cons of membrane materials for separation of organic mixtures are reviewed. • Upper-bounds of PV/VP membranes for separation of organic mixtures are plotted. • From materials and processes analyze transport mechanism of organic molecules. Separation of organic-organic solvent mixtures is energy-intensive by using conventional methods, which is also a challenging task for membrane technology. Over the past decade, pervaporation (PV) and vapor permeation (VP) have been continuously studied for the separation of organic solvent mixtures. The PV and VP processes are limited by thermodynamic vapor–liquid equilibrium (VLE) and thus consume less energy compared with conventional distillation technology. In this review, we focus on the membrane materials toward organic solvent PV/VP separation, including polymeric membranes, microporous membranes, mixed-matrix membranes and other emerging membranes, and separation systems in the recent decade, and define the current state-of-the-art for membrane materials and performance. The separation mechanism of different membrane materials such as affinity and size sieving, or the synergy of both is discussed, aiming to understand the priority permeation orders in different types of membrane materials, and provide fundamental insights for the design of high-performance membrane materials and structures. Additionally, the PV/VP process is compared with reverse osmosis (RO) process toward organic solvent separation in terms of membrane materials, separation performance and transport mechanism. Finally, we outlook the potential opportunities and challenges of applying advanced membrane materials for PV/VP separation of organic solvent mixtures. [ABSTRACT FROM AUTHOR]

[Display omitted] • The optimal adsorption configuration, adsorption energy and forming bonds involved in adsorption is visualized and quantified. • BTX adsorption was driven by hydrophobic interaction and weak hydrogen bond. • Adsorption process was well described by the Langmuir-Freundlich isotherm model and pseudo-first order kinetic. • Benzene had an advantage over m-xylene during the competition adsorption process. Benzene, toluene and m-xylene (BTX) pollution due to industrial development has been a serious problem in recent years. The environmental mobility and fate of BTX in soils are mainly controlled by interactions with soil minerals such as kaolinite. Therefore, it is crucial to characterise the molecular-scale interactions that occur between BTX and kaolinite. In this study, molecular dynamics (MD) simulations, isothermal titration calorimetry (ITC) and batch adsorption experiments were performed to investigate the molecular interactions between BTX and kaolinite. Results revealed that the adsorption capacity of the kaolinite 00 1 ¯ surface was stronger than that of the kaolinite 001 surface due to the weaker hydrophilicity. BTX molecules were adsorbed on kaolinite surfaces by forming weak hydrogen bonds with the oxygen basal surface. The adsorption energy and adsorption isotherm obtained by the MD simulations were similar to those from the ITC and batch experiments, which validated the reliability of the MD simulations. The adsorption of BTX onto kaolinite was well described by the pseudo first-order kinetic and Langmuir-Freundlich isotherm model. Overall, performing MD simulations combined with experiments revealed the BTX adsorption mechanisms from a molecular interaction perspective. [ABSTRACT FROM AUTHOR]