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Ethylene is a vital intermediate in the petrochemical industry, and its purification from a C 2 ternary mixture of up to 99.9% is essential to obtain a polymer-grade gas in an energy-demanding process. Adsorption-based separation offers an alternative approach for ethylene purification in a one-step process. Here, we report the fabrication of a monolithic composite from a zeolite-like metal-organic framework with a sodalite topology (sod -ZMOF) incorporated into a divinylbenzene polymer (ZMOF@DVB), to purify ethylene from binary and ternary mixtures of C 2 hydrocarbons. The monolithic structure provides the composite with mechanical stability and high permeability, while only 2.31 wt% loading of sod- ZMOF nanoparticles has increased the BET surface area by 2.5 times, focused the pore size at 10.1 Å, and allowed for specific interactions. Gas chromatography was used to investigate the separation performance of the composite, reviling a quite satisfying selectivity of ethane/ethylene (1.89) and acetylene/ethylene (1.28), with comparable values to those of benchmark adsorbents used for similar applications and calculated via the ideal adsorbed solution theory (IAST). It is proposed that the anionic framework boosted the high polarizable ethane molecules' adsorption over ethylene; on the other hand, the Lewis basic nature of the extra-framework imidazolium cations neutralizes the anionic ZMOF structure drives acetylene's preferential adsorption over ethylene. As a proof of concept, imidazolium cations were exchanged in-situ by Na+ cations, and selectivities decreased to 1.37 for ethane/ethylene and 1.15 for acetylene/ethylene. An inverse gas chromatography approach was utilized to evaluate the thermodynamic parameters and showed an enthalpic-entropic motivated separation before cation exchange. However, after removing bulky imidazolium cations, separation became more entropic-driven. [Display omitted] • Gas chromatography is a fast and efficient technique to investigate gas separation ability. • sod -ZMOF nanoparticles incorporation boosts DVB-monolithic polymer ability of ethylene purification from a ternary mixture. • In-situ cation exchange of sod- ZMOF proved the role of imidazolium ions in ethylene selectivity in a one-step purification. • Deeper insights into separation mechanisms were provided by inverse gas chromatography – a physicochemical study. [ABSTRACT FROM AUTHOR]

Abstract: Spherical shaped anatase nanoparticles (ø 5nm) have been synthesized in the ionic liquid 1-(3-hydroxypropyl)-3-methylimidazolium-bis(trifluoromethanesulfonyl)amide from titanium tetraisopropoxide by ultrasound assisted synthesis under ambient conditions. XRD, EDX, TEM, XPS, Raman, UV–vis, PL and BET measurements have been employed for characterization of the nanostructure of as-prepared TiO2. XRD and Raman measurements both show that the obtained material is crystalline with anatase structure. The morphology of TiO2 nanoparticles was characterized by transmission electron microscopy (TEM). The bandgap of the TiO2 nanocrystals estimated from XRD and UV–vis measurements is about 3.3eV. The surface area of a typical sample is 177m2 g−1. The synthesized anatase nanocrystals show good photocatalytic activity in the degradation of methylorange. [Copyright &y& Elsevier]

Asymmetric block copolymer membranes can be facilely prepared via non-solvent induced phase separation combined with self-assembly. The membrane is characterized by a thin layer of highly ordered and uniform cylindrical nano-channels on top of a non-ordered macroporous sponge-like layer. Up to date, most studies concerning block copolymer membranes are focused on separation applications. In this work, highly adsorptive and adhesive isoporous block copolymer membranes have been fabricated. Because of the functionalization with cyclodextrin, the membrane shows excellent affinity to guest molecules. Moreover, the membrane is biocompatible and is adhesive to various substrates (e.g. glass, silicon, gold and stainless steel). Triclosan as a model drug was utilized to demonstrate the applicability of the membranes as a drug reservoir. A high loading capacity (305.5 μg cm−2) was achieved. The release behavior was investigated under various pH values in vitro. A long-time extended drug release was achieved without showing an initial burst effect. Furthermore, pH-responsive release behavior was observed. The triclosan-loaded membrane exhibited a significant antibacterial effect due to the triclosan release; the diffusion out of the membrane was evaluated using a disc diffusion assay. This study provides great potential for isoporous block copolymer membranes as a delivery platform for a wide variety of biomedical applications. Image 1 • Cyclodextrin-functionalized isoporous block copolymer membranes were manufactured. • The modified membranes showed excellent affinity for guest molecules. • The modified membranes showed excellent adhesion capability to various substates. • High loading capacity of triclosan and subsequent pH responsive controlled release were observed. [ABSTRACT FROM AUTHOR]