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The characteristics of water vapor adsorption depend on the structure, porosity, and functional groups of the material. Metal–organic framework (MOF)-derived carbon (MDC) is a novel material that exhibits a high specific area and tunable pore sizes by exploiting the stable structure and porosity of pure MOF materials. Herein, two types of aluminum-based MOFs were used as precursors to synthesize hydrophobic microporous C-MDC and micro-mesoporous A-MDC via carbonization and activation depending on the type of ligands in the precursors. C-MDC and A-MDC have different pore characteristics and exhibit distinct water adsorption properties. C-MDC with hydrophobic properties and micropores exhibited negligible water adsorption (108.54 mgg−1) at relatively low pressures (P/P0~0.3) but showed a rapid increase in water adsorption ability (475.7 mgg−1) at relative pressures of about 0.6. A comparison with the isotherm model indicated that the results were consistent with the theories, which include site filling at low relative pressure and pore filling at high relative pressure. In particular, the Do–Do model specialized for type 5 showed excellent agreement. [ABSTRACT FROM AUTHOR]

The characteristics of water vapor adsorption depend on the structure, porosity, and functional groups of the material. Metal–organic framework (MOF)-derived carbon (MDC) is a novel material that exhibits a high specific area and tunable pore sizes by exploiting the stable structure and porosity of pure MOF materials. Herein, two types of aluminum-based MOFs were used as precursors to synthesize hydrophobic microporous C-MDC and micro-mesoporous A-MDC via carbonization and activation depending on the type of ligands in the precursors. C-MDC and A-MDC have different pore characteristics and exhibit distinct water adsorption properties. C-MDC with hydrophobic properties and micropores exhibited negligible water adsorption (108.54 mgg−1) at relatively low pressures (P/P0~0.3) but showed a rapid increase in water adsorption ability (475.7 mgg−1) at relative pressures of about 0.6. A comparison with the isotherm model indicated that the results were consistent with the theories, which include site filling at low relative pressure and pore filling at high relative pressure. In particular, the Do–Do model specialized for type 5 showed excellent agreement.

The topology and chemical functionality of metal–organic frameworks (MOFs) make them promising candidates for membrane gas separation; however, few meet the criteria for industrial applications, that is, selectivity of >30 for CO2/CH4 and CO2/N2. This paper reports on a dense CAU‐10‐H MOF membrane that is exceptionally CO2‐selective (ideal selectivity of 42 for CO2/N2 and 95 for CO2/CH4). The proposed membrane also achieves the highest CO2 permeability (approximately 500 Barrer) among existing pure MOF membranes with CO2/CH4 selectivity exceeding 30. State‐of‐the‐art atomistic simulations provide valuable insights into the outstanding separation performance of CAU‐10‐H at the molecular level. Adsorbent–adsorbate Coulombic interactions are identified as a crucial factor in the design of CO2‐selective MOF membranes. [ABSTRACT FROM AUTHOR]

Abstract Well-intergrown hydrophilic CAU-10-H membranes were successfully prepared by microwave-assisted secondary growth. The as-synthesized CAU-10-H membranes exhibited high and reproducible performance for ethanol dehydration. For a 90 wt% ethanol feed, the CAU-10-H membrane had a total flux of 493 g m-2 h-1 and water/ethanol separation factor of 148 at 65 °C. Along with the increasing temperature or water feed concentration, the total flux increased while the water/ethanol separation factor decreased. The ideal water/ethanol selectivities of the CAU-10-H membranes were found to be significantly lower than its membrane selectivities, demonstrating that the preferential adsorption of water on hydrophilic CAU-10-H membrane to hinder ethanol transport played a prominent part in the ethanol-water separation. The CAU-10-H membranes are capable of being used in acidic conditions, and therefore showing great prospects for industrial applications. Highlights • Hydrophilic CAU-10-H is stable in water at 80 °C around 190 h. • A dense CAU-10-H membrane was synthesized by microwave-assisted secondary growth. • CAU-10-H membranes showed high pervaporation performance for ethanol dehydration. • The performance of CAU-10-H membranes remained unchanged under acidic conditions. [ABSTRACT FROM AUTHOR]

There remains a great challenge to develop a switchable and feasible membrane for integrate reversible separation of oil/water mixtures. Herein, a highly-quality CAU-10-H mesh membrane with switchable superwettability was fabricated via solvothermal synthesis for on-demand oil/water separation. The CAU-10-H membrane exhibited under-liquid dual superlyophobicity due to the hierarchical micro-/nanostructures constructed by interpenetrating CAU-10-H crystals grown on the mesh. Meanwhile, the secondary growth time affecting the wetting behavior of the membrane is studied. More importantly, the membrane can achieve both immiscible oil/water separation and emulsion separation with high separation flux and high efficiency (>99.9%). Moreover, the membrane shows an excellent anti-corrosive property in various harsh environment. The present development would provide novel insights into the rational fabrication of MOF-based membranes for on-demand oil/water separation. [Display omitted] • Switchable superwetting CAU-10-H mesh membrane was prepared. • The membrane exhibited under-liquid dual superlyophobicity due to the hierarchical micro-/nanostructures. • The membrane achieves on-demand separation of immiscible oil/water mixtures and emulsions. • The membrane exhibits excellent anti-corrosive property towards harsh environment. [ABSTRACT FROM AUTHOR]

On the basis of the method used by Reinsch and Solovyeva, the aluminum based MOF material CAU-10-H (CAU stand for Christian-Albrechts-University) was synthesized by multiplying the amount of aluminum sulfate octahydrate and isophthalic acid by 10 times. CAU-10-H (b) is obtained after washing. In order to improve the water vapor adsorption performance of pure CAU-10-H (b), lithium chloride (LiCl) solution was compounded with CAU-10-H (b) by impregnation method to obtain a composite adsorbent CAU-10-H (L) and its adsorption characteristics were studied. The results showed that the composite adsorbent showed good adsorption and desorption performance under test conditions. Among them, the equilibrium adsorption capacity of the composite adsorbent with 33.1% LiCl content is 0.5007 g/g after 30 cycles, which is about 1.675 times of the adsorption capacity of pure CAU-10-H (b) under the same conditions. This shows the potential of the composite adsorbent to be used in the air-water extraction system. In this paper, aluminum based MOF material CAU-10-H [Al (OH) (m -BDC) 2, CAU stand for Christian Albrechts University] was synthesized. The performance test proves the performance advantage of CAU-10-H (b). In order to improve the adsorption performance of the adsorbent, the composite adsorbent CAU-10-H (L) was synthesized by impregnation. The composite adsorbent showed good desorption performance. This demonstrates the potential of the composite adsorbent for use in air-water extraction systems. [Display omitted] • Aluminum based MOF: CAU-10-H (CAU stand for Christian-Albrechts-University) was prepared by solvothermal synthesis using aluminum sulfate octahydrate and isophthalic acid as raw materials. • The sample of CAU-10-H after washing is named CAU-10-H (b). The microstructure characterization and open adsorption performance tests were done for CAU-10-H(b). • In order to improve the water vapor adsorption performance of CAU-10-H (b), a composite adsorbent CAU-10-H (L) was synthesized by impregnating CAU-10-H (b) with lithium chloride (LiCl) solution. • The water vapor adsorption capacity of the composite adsorbent is higher than that of CAU-10-H (b). The equilibrium adsorption capacity of the composite adsorbent with a mass fraction of 33.1% LiCl is about 1.675 times that of CAU-10-H (b). • The composite adsorbent has good desorption performance, high desorption rate, low desorption temperature, and can reduce energy consumption in practical application. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are highly compatible with polymers and can be used to create mixed matrix membranes (MMMs) for gas separation. Herein, we engineered the particle size as well as the number of missing linkers in CAU-10-H MOFs via either applying the plasma treatment (CAU-10-H_Plasma) or varying the water/ N , N -dimethylformamide (H 2 O/DMF) co-solvent ratios (CAU-10-H_Micro and CAU-10-H_Nano). The CAU-10-H_Nano showed the largest number of missing linkers, but the lowest adsorption uptake of CO 2 and CH 4 albeit the largest BET surface area. In contrast, both CAU-10-H_Plasma and CAU-10-H_Micro exhibited relatively high adsorption uptakes of CO 2 and CH 4. In addition, all the MMMs fabricated using 6FDA-mPDA:DABA (3:2) exhibited a good interaction between Al2+ metal ions of CAU-10-H and carboxylic groups of 6FDA-mPDA:DABA (3:2). Importantly, the 6FDA-mPDA:DABA (3:2)/CAU-10-H_Plasma (75/25 w/w) MMM exhibited more attractive selectivities of CO 2 /CH 4 and H 2 /CH 4 (e.g., 68 and 184, respectively) compared to those of the other two MMMs under single-gas conditions. It also showed the highest CO 2 /CH 4 selectivity of 67 under equimolar CO 2 /CH 4 mixed-gas conditions. As CAU-10-H_Plasma possessed the lowest quantity of defective sites among the three CAU-10-H samples, our results suggest that suppressing defective sites in MOFs could be an effective approach for enhancing the CO 2 separation efficiency. [Display omitted] • Emerging MOF, CAU-10-H, is used for preparation of MMMs. • Plasma-assisted synthesis of CAU-10-H is employed for the size and defect control. • The CAU-10-H/6FDA-mPDA:DABA (3:2)-based MMM presents CO 2 /CH 4 selectivity of 67. [ABSTRACT FROM AUTHOR]