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Achieving homogeneous dispersion of nanoporous fillers within membrane architectures remains a great challenge for mixed-matrix membrane (MMMs) technology. Imparting solution processability of nanoporous materials would help advance the development of MMMs for membrane-based gas separations. A mechanochemically assisted oxidative coupling polymerization strategy was used to create a new family of soluble nanoporous polymer networks. The solid-state ball-milling method affords inherent molecular weight control over polymer growth and therefore provides unexpected solubility for the resulting nanoporous frameworks. MMM-based CO2 /CH4 separation performance was significantly accelerated by these new soluble fillers. We anticipate this facile method will facilitate new possibilities for the rational design and synthesis of soluble nanoporous polymer networks and promote their applications in membrane-based gas separations.

A rational design and synthesis of covalent organic frameworks (COFs) displaying efficient adsorption of surrogates for common organic pollutants is demonstrated herein. Significantly, the top performing mesoporous triazine-functionalized polyimide COF exhibits superior adsorption of the small dye molecule methylene blue, achieving a maximum adsorption capacity of ∼1691 mg g−1 (∼169 wt %), surpassing the performance of all previously reported nanoporous adsorbents. The experimental results and accompanying in silico simulations suggest that both the size of the organic dye molecules and the intrinsic pore-size effect of the COF material should be taken into account simultaneously for the construction of COF-based adsorbents with efficient dyes adsorption capacities. The structural diversity of COF materials along with the understanding of the encapsulation of organic dyes on COFs holds great promise for developing novel COF adsorbents for the efficient removal of organic pollutants from wastewater. © 2017 American Institute of Chemical Engineers AIChE J, 63: 3470–3478, 2017

An innovative wet-treatment with Na2 S transforms two indium metal-organic frameworks (MOFs) into a series of porous inorganic sorbents. These MOF-templated materials display remarkable affinity for heavy metals with saturation occurring in less than 1 h. The saturation capacity for Hg(II) exceeds 2 g g(-1) , more than doubling the best thiol-functionalized sorbents in the literature.

The catalysts are recycled and reused in up to ten catalytic cycles without loss of activity.

The potential consequences of nuclear events and the complexity of nuclear waste management motivate the development of selective solid-phase sorbents to provide enhanced protection. Herein, it is shown that 2D covalent organic frameworks (COFs) with unique structures possess all the traits to be well suited as a platform for the deployment of highly efficient sorbents such that they exhibit remarkable performance, as demonstrated by uranium capture. The chelating groups laced on the open 1D channels exhibit exceptional accessibility, allowing significantly higher utilization efficiency. In addition, the 2D extended polygons packed closely in an eclipsed fashion bring chelating groups in adjacent layers parallel to each other, which may facilitate their cooperation, thereby leading to high affinity toward specific ions. As a result, the amidoxime-functionalized COFs far outperform their corresponding amorphous analogs in terms of adsorption capacities, kinetics, and affinities. Specifically, COF-TpAb-AO is able to reduce various uranium contaminated water samples from 1 ppm to less than 0.1 ppb within several minutes, well below the drinking water limit (30 ppb), as well as mine uranium from spiked seawater with an exceptionally high uptake capacity of 127 mg g-1 . These results delineate important synthetic advances toward the implementation of COFs in environmental remediation.

Ti and Zr nanoscale metal-organic frameworks (MOFs) are prepared from a mixture of Ti(O-iPr)4, terephthalic acid, DMF, and EtOH (autoclave, 150 °C, 20 h) and from a mixture of terephthalic acid, benzoic acid, DMF, and ZrCl4 (autoclave, 120 °C, 20 h).

The primary challenge in materials design and synthesis is achieving the balance between performance and economy for real-world application. This issue is addressed by creating a thiol functionalized porous organic polymer (POP) using simple free radical polymerization techniques to prepare a cost-effective material with a high density of chelating sites designed for mercury capture and therefore environmental remediation. The resulting POP is able to remove aqueous and airborne mercury with uptake capacities of 1216 and 630 mg g-1 , respectively. The material demonstrates rapid kinetics, capable of dropping the mercury concentration from 5 ppm to 1 ppb, lower than the US Environmental Protection Agency's drinking water limit (2 ppb), within 10 min. Furthermore, the material has the added benefits of recyclability, stability in a broad pH range, and selectivity for toxic metals. These results are attributed to the material's physical properties, which include hierarchical porosity, a high density of chelating sites, and the material's robustness, which improve the thiol availability to bind with mercury as determined by X-ray photoelectron spectroscopy and X-ray absorption fine structure studies. The work provides promising results for POPs as an economical material for multiple environmental remediation applications.

This tutorial review presents recent developments of homochiral metal–organic frameworks (MOFs) in enantioselective catalysis. Following a brief introduction of the basic concepts and potential virtues of MOFs in catalysis, we summarize three distinct strategies that have been utilized to synthesize homochiral MOFs. Framework stability and accessibility of the open channels to reagents are then addressed. We finally survey recent successful examples of catalytically active homochiral MOFs based on three approaches, namely, homochiral MOFs with achiral catalytic sites, incorporation of asymmetric catalysts directly into the framework, and post-synthetic modification of homochiral MOFs. Although still in their infancy, homochiral MOFs have clearly demonstrated their utility in heterogeneous asymmetric catalysis, and a bright future is foreseen for the development of practically useful homochiral MOFs in the production of optically pure organic molecules.

The visceromotor response to balloon distension of the colon is a robust behavioral model of visceral nociception in rodents and is ideally suited for studying the visceral antinociceptive activity of drugs. This unit describes, in detail, quantification of this response with the use of electromyography in both rats and mice. Keywords: Electromyography; Visceromotor; Colon; Balloon; Mouse; Rat