Mixed matrix membranes containing metal-organic frameworks have attracted large attention owing to the combined advantages of high separation performance and easy processability. In this work, ...CO2-philic zirconium metal organic framework UiO-66 and UiO-66-NH2 nanocrystals were synthesized and embedded into polyether block amide (PEBA) polymer membranes for CO2 separation. It can be found that amine-functionalization endowed UiO-66-NH2 nanoparticles with stronger CO2 affinity compared with that of UiO-66. Also, the hydrogen bonding frameworks between UiO-66-NH2 and PEBA were enhanced, leading to improved dispersibility in polymer matrix. Both the UiO-66-PEBA and UiO-66-NH2-PEBA mixed matrix membranes showed much higher CO2 separation performance than that of pure PEBA membrane. Especially, amine functionalization of the porous frameworks provided the so-prepared UiO-66-NH2-PEBA mixed matrix membrane with higher CO2/N2 selectivity and slightly decreased CO2 permeability than those of UiO-66-PEBA membrane. The developed UiO-66-NH2-PEBA mixed matrix membrane (with MOFs loading of 10wt%) was tested in humid state and showed excellent and stable CO2/N2 separation performance (CO2 permeability of 130Barrer, CO2/N2 selectivity of 72) surpassing the upper bound of polymer membranes. This type of UiO-66 based mixed matrix membranes featuring with excellent structural stability and significantly improved gas separation performance offer promising potential for CO2 capture.
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•UiO-66 based MOFs-PEBA MMMs were designed and fabricated.•Amine functionalization improved the crystals dispersibility and CO2 affinity.•UiO-66-NH2-PEBA membrane showed significantly enhanced CO2 separation performance.•UiO-66-NH2-PEBA membrane exhibited good stability under humid state.
Membrane‐based separation is poised to reduce the operation cost of propylene/propane separation; however, identifying a suitable molecular sieve for membrane development is still an ongoing ...challenge. Here, the successful identification and use of a metal–organic framework (MOF) material as fillers, namely, the Zr‐fum‐fcu‐MOF possessing an optimal contracted triangular pore‐aperture driving the efficient diffusive separation of propylene from propane in mixed‐matrix membranes are reported. It is demonstrated that the fabricated hybrid membranes display a high propylene/propane separation performance, far beyond the current trade‐off limit of polymer membranes with excellent properties under industrial conditions. Most importantly, the mechanism behind the exceptional high propylene/propane selectivity is delineated by exploring theoretically the efficiency of sieving of different conformers of propane through the hypothesized triangular rigid pore‐aperture of Zr‐fum‐fcu‐MOF.
The traditional understanding of the molecular sieving effect is refined by considering the CC single bond rotation in C3H6 and C3H8 molecules. Zr‐fum‐fcu‐MOF with trefoil‐like pore‐aperture is therefore rationally selected as efficient C3H6/C3H8 fillers in mixed matrix membranes (MMMs). The fabricated MMMs shows excellent C3H6/C3H8 separation performance, far beyond the trade‐off of polymer membranes.
In this work, ceramic hollow fiber supported polydimethylsiloxane (PDMS) composite membranes were developed by dip-coating PDMS layer on the surface of macroporous ceramic hollow fiber support. By ...controlling the properties of polymer solution and ceramic hollow fiber, high-quality ceramic hollow fiber supported PDMS composite membranes were fabricated for pervaporation (PV) recovery of bio-butanol. It was found both the viscosity of PDMS dip-coating solution and pore size and structure of ceramic support played critical roles in determining the microstructures, the mass transport and the PV performance of PDMS composite membrane. The optimized composite membrane with defect-free PDMS layer and low transport resistance of support showed a total flux of 1282g/m2h and separation factor of 42.9 for 1wt% n-butanol–water mixtures at temperature of 40°C during 200h continuous operation. In addition, the membrane PV performance and stability in acetone–butanol–ethanol (ABE) fermentation broth were investigated. The results showed the PDMS composite membrane exhibited high and stable performance for butanol recovery from ABE systems. Compared with literatures, our work demonstrated that the ceramic hollow fiber supported PDMS composite membrane could be a competitive PV membrane for recovering organic compounds from fermentation broth to produce renewable biofuels.
•Ceramic hollow fiber supported PDMS composite membrane is developed.•Coating solution viscosity and supports are critical for forming PDMS layer.•PDMS composite membrane is used for ABE recovery from fermentation broth.•PDMS composite membrane shows high performance for PV of n-butanol–water mixture.
•GO/ceramic composite membrane was prepared by facile dip-coating method.•Interfacial adhesion of the membrane was improved by silane-modification.•GO/ceramic composite membrane shows potential for ...small molecule separation.
Graphene oxide (GO) composite membrane was fabricated on a silane-modified ceramic support via dip-coating method. The modification of ceramic support by saline improves the interfacial adhesion with GO membrane layer. Meanwhile, the automatic capillary filtration process of ceramic support enables the preparation simple. SEM, EDS, XRD, FT-IR, AFM, nanoindentor and contact angle measurements were conducted to study the morphologies, physical and chemical properties and surface properties of the GO/ceramic composite membrane. The membrane exhibits good integrity, continuity and strong interfacial adhesion, and the surface of GO/ceramic composite membrane is hydrophilic. Additionally, the pervaporation performance of the GO/ceramic composite membrane for separation water from ethanol/water mixtures was investigated, showing a total flux of 461.86g/(m2h) and a water concentration enhancement from 5wt% to 39.92wt% at 40°C.
Major depressive disorder (MDD) is a life‐threatening illness characterized by mood changes and high rates of suicide. Although the role of neuroinflammation in MMD has been studied, the mechanistic ...interplay between antidepressants, neuroinflammation, and autophagy is yet to be investigated. The present study investigated the effect of melatonin on LPS‐induced neuroinflammation, depression, and autophagy impairment. Our results showed that in mice, lipopolysaccharide (LPS) treatment induced depressive‐like behaviors and caused autophagy impairment by dysregulating ATG genes. Moreover, LPS treatment significantly increased the levels of cytokines (TNFα, IL‐1β, IL‐6), enhanced NF‐ᴋB phosphorylation, caused glial (astrocytes and microglia) cell activation, dysregulated FOXO3a expression, increased the levels of redox signaling molecules such as ROS/TBARs, and altered expression of Nrf2, SOD2, and HO‐1. Melatonin treatment significantly abolished the effects of LPS, as demonstrated by improved depressive‐like behaviors, normalized autophagy‐related gene expression, and reduced levels of cytokines. Further, we investigated the role of autophagy in LPS‐induced depressive‐like behavior and neuroinflammation using autophagy inhibitors 3‐MA and Ly294002. Interestingly, inhibitor treatment significantly abolished and reversed the anti‐depressive, pro‐autophagy, and anti‐inflammatory effects of melatonin. The present study concludes that the anti‐depressive effects of melatonin in LPS‐induced depression might be mediated via autophagy modulation through FOXO3a signaling.
Thin film composite (TFC) membranes have attracted great research interest for a wide range of separation processes owing to their potential to achieve excellent permeance. However, it still remains ...challenging to fully exploit the superiority of thin selective layers when mitigating the pore intrusion phenomenon. Herein, a facile and generic interface‐decoration‐layer strategy collaborating with molecular‐scale organic–inorganic hybridization in the selective layer to obtain a high‐performance ultrathin film composite (UTFC) membrane for CO2 capture is reported. The interface‐decoration layer of copper hydroxide nanofibers (CHNs) enables the formation of an ultrathin selective layer (≈100 nm), achieving a 2.5‐fold increase in gas permeance. The organic part in the molecular‐scale hybrid material contributes to facilitating CO2‐selective adsorption while the inorganic part assists in maintaining robust membrane structure, thus remarkably improving the selectivity toward CO2. As a result, the as‐prepared membrane shows a high CO2 permeance of 2860 GPU, superior to state‐of‐the‐art polymer membranes, with a CO2/N2 selectivity of 28.2. The synergistic strategy proposed here can be extended to a wide range of polymers, holding great potential to produce high‐efficiency ultrathin membranes for molecular separation.
A facile and generic interface‐decoration‐layer strategy collaborating with molecular‐scale hybridization in the selective layer is proposed to obtain an ultrathin film composite membrane with both high gas permeance and selectivity, superior to state‐of‐the‐art polymer membranes.
The basolateral amygdala (BLA) and ventral hippocampal CA1 (vCA1) are cellularly and functionally diverse along their anterior-posterior and superficial-deep axes. Here, we find that anterior BLA ...(aBLA) and posterior BLA (pBLA) innervate deep-layer calbindin1-negative (Calb1-) and superficial-layer calbindin1-positive neurons (Calb1+) in vCA1, respectively. Photostimulation of pBLA-vCA1 inputs has an anxiolytic effect in mice, promoting approach behaviours during conflict exploratory tasks. By contrast, stimulating aBLA-vCA1 inputs induces anxiety-like behaviour resulting in fewer approaches. During conflict stages of the elevated plus maze task vCA1
neurons are preferentially activated at the open-to-closed arm transition, and photostimulation of vCA1
neurons at decision-making zones promotes approach with fewer retreats. In the APP/PS1 mouse model of Alzheimer's disease, which shows anxiety-like behaviour, photostimulating the pBLA-vCA1
circuit ameliorates the anxiety in a Calb1-dependent manner. These findings suggest the pBLA-vCA1
circuit from heterogeneous BLA-vCA1 connections drives approach behaviour to reduce anxiety-like behaviour.
With versatile chemical and engineering design, the more attention of metal-organic framework (MOF) material is shifting from its fundamental studies to industrial applications, such as engineering ...MOF adsorbents and membranes for selective guest capture and separations. Learned from zeolites, various effective strategies in material design, adsorbents assembly, and membranes fabrication have enabled the MOFs gradually to approach high industrial standards, bearing their unique chemical and physical properties. In this review, we focus on the important factors that may affect the practical applications of MOF adsorbents and MOF membranes.
Membrane‐based gas separations are energy efficient processes; however, major challenges remain to develop high‐performance membranes enabling the replacement of conventional separation processes. ...Herein, a new fluorinated MOF‐based mixed‐matrix membrane is reported, which is formed by incorporating the MOF crystals into selected polymers via a facile mixed‐matrix approach. By finely controlling the molecular transport in the channels through the MOF apertures tuned by metal pillars and at the MOF‐polymer interfaces, the resulting fluorinated MOF‐based membranes exhibit excellent molecular sieving properties. These materials significantly outperform state‐of‐the‐art membranes for simultaneous removal of H2S and CO2 from natural gas—a challenging and economically important application. The robust fluorinated MOFs (NbOFFIVE‐1‐Ni, AlFFIVE‐1‐Ni), pave a way to efficient membrane separation processes that require precise discrimination of closely sized molecules.
Separate ways: New fluorinated metal–organic framework (MOF)‐based mixed‐matrix membranes with finely controlled molecular transport in the channels through the MOF aperture exhibit excellent molecular‐sieving properties that significantly outperform state‐of‐the‐art membranes for simultaneous removal of H2S and CO2 from natural gas.
Bio-butanol is an important aspect for development of renewable energy. Currently, it remains challenging for developing highly permeable and selective composite membranes to efficiently recover ...butanol produced in biomass fermentation process. In this work, we fabricated polydimethylsiloxane (PDMS) into thin and defect-free composite membranes by using porous PVDF as the substrate. The formation of PDMS membrane layer was finely controlled by optimizing the substrate pore size and casting solution viscosity. In particular, the interfacial adhesion between PDMS active layer and PVDF substrate layer, which is critical for practical application of composite membrane, was probed by using in-situ nano-indentation/scratch technique for the first time. The transport properties of the prepared PDMS/PVDF composite membranes were studied by pervaporation recovery of n-butanol from aqueous solution with different feed concentrations or temperatures. The results indicated that the PDMS membrane layer with a carefully tuned thickness of ∼11 μm offered high total flux of 2210 g/m2h and excellent separation factor of 46 (1 wt% butanol/water at 70 °C), as well as strong interfacial adhesion for the PDMS/PVDF composite membrane. The separation performance is superior to the reported membranes, showing great potential for application in bio-butanol separation.
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•Thin and defect-free PDMS/PVDF composite membrane is prepared.•Interfacial adhesion of PDMS/PVDF composite membrane is measured.•PDMS/PVDF composite membrane shows excellent butanol/water separation performance.
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