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Introduction of Ag(i) ions into a sulfonic acid functionalized MOF ((Cr)-MIL-101-SO3H) significantly enhances its interactions with olefin double bonds, leading to its much higher selectivities for the separation of C2H4-C2H6 and C3H6-C3H8 at room temperature over the original (Cr)-MIL-101-SO3H and other adsorbents at room temperature.

Pioglitazone has been developed as an effective insulin-sensitizing agent for the treatment of type II diabetes mellitus. Selective hydrogenation of the benzylidenethiazolidinedione exocyclic alkene is a committed step in the industrial manufacturing of pioglitazone. However, the strong coordination between metallic sites of commercial hydrogenation catalysts and benzylidenethiazolidinedione might cause catalyst poisoning and lead to poor activity and selectivity. In this context, an effective and anti-poisoning catalyst with highly dispersed palladium nanoparticles supported on biomass-derived nitrogen-doped carbon with mesoporous structures has been established. A systematic investigation of the structure–activity relationship was performed with a series of Pd/CNx by regulating the ratio of precursors D-glucosamine hydrochloride (GAH) and melamine, and it demonstrated that large specific surface area, rich pore structure and strong Pd–N interaction were essential for the high catalytic performance. The optimal Pd/CN1.2 catalyst exhibited nearly 100% conversion and 95.5% selectivity under optimized reaction conditions. Remarkably, compared with commercial Pd/C catalyst, Pd/CN1.2 displayed almost twice the catalytic productivity and provided better poisoning resistance and leaching resistance. Moreover, its stability was also acceptable and good activity could be maintained after exposed in the air for 4 months. [ABSTRACT FROM AUTHOR]

C2‐C3 alkyne/alkene separation is of great importance; however, designing materials for an efficient molecular sieving of alkenes from alkynes remains challenging. Now, two hydrolytically stable layered MOFs, [Cu(dps)2(GeF6)] (GeFSIX‐dps‐Cu, dps=4,4′‐dipyridylsulfide) and [Zn(dps)2(GeF6)] (GeFSIX‐dps‐Zn), can achieve almost complete exclusion of both C3H6 and C2H4 from their alkyne analogues. GeFSIX‐dps‐Cu displays a notable advanced threshold pressure for alkynes adsorption and thus substantial uptakes at lower pressures, providing record C3H4/C3H6 uptake ratios and capacity‐enhanced C2H2/C2H4 sieving for a wide composition range. Metal substitution (Zn to Cu) affords fine tuning of linker rotation and layer stacking, creating slightly expanded pore aperture and interlayer space coupled with multiple hydrogen‐bonding sites, allowing easier entrance of alkyne while excluding alkene. Breakthrough experiments confirmed tunable sieving by these MOFs for C3H4/C3H6 and C2H2/C2H4 mixtures. [ABSTRACT FROM AUTHOR]

The separation of acetylene from ethylene is of paramount importance in the purification of chemical feedstocks for industrial manufacturing. Herein, an isostructural series of gallate‐based metal–organic frameworks (MOFs), M‐gallate (M=Ni, Mg, Co), featuring three‐dimensionally interconnected zigzag channels, the aperture size of which can be finely tuned within 0.3 Å by metal replacement. Controlling the aperture size of M‐gallate materials slightly from 3.69 down to 3.47 Å could result in a dramatic enhancement of C2H2/C2H4 separation performance. As the smallest radius among the studied metal ions, Ni‐gallate exhibits the best C2H2/C2H4 adsorption separation performance owing to the strongest confinement effect, ranking after the state‐of‐the‐art UTSA‐200a with a C2H4 productivity of 85.6 mol L−1 from 1:99 C2H2/C2H4 mixture. The isostructural gallate‐based MOFs, readily synthesized from inexpensive gallic acid, are demonstrated to be a new top‐performing porous material for highly efficient adsorption of C2H2 from C2H4. [ABSTRACT FROM AUTHOR]

C4 olefin separations present one of the great challenges in hydrocarbon purifications owing to their similar structures, thus a single separation mechanism often met with limited success. Herein we report a series of anion-pillared interpenetrated copper coordination for which the cavity and functional site disposition can be varied in 0.2 Å scale increments by altering the anion pillars and organic linkers (GeFSIX-2-Cu-i (ZU-32), NbFSIX-2-Cu-i (ZU-52), GeFSIX-14-Cu-i (ZU-33)), which enable selective recognition of different C4 olefins. In these materials the rotation of the organic linkers is controlled to create a contracted flexible pore window that enables the size-exclusion of specific C4 olefins, while still adsorbing significant amounts of 1,3-butadiene (C4H6) or 1-butene (n-C4H8). Combining the molecular recognition and size-sieving effect, these materials unexpectedly realized the sieving of C4H6/n-C4H8, C4H6/iso-C4H8, and n-C4H8/iso-C4H8 with high capacity. [ABSTRACT FROM AUTHOR]

Introduction of Ag(i) ions into a sulfonic acid functionalized MOF ((Cr)-MIL-101-SO3H) significantly enhances its interactions with olefin double bonds, leading to its much higher selectivities for the separation of C2H4–C2H6 and C3H6–C3H8 at room temperature over the original (Cr)-MIL-101-SO3H and other adsorbents at room temperature. [ABSTRACT FROM AUTHOR]

Shaping metal-organic frameworks (MOFs) powders into formed bodies plays a crucial role in opening up the excellent properties of MOFs to a broad range of applications. Gallate-based MOFs, termed as M-gallate (M = Co, Mg, Ni), have shown excellent performance for adsorption separation of C 2 hydrocarbons. However, the industrial applications of MOF powders will inevitably confront problems of high pressure drop, pipe blockage, and dust pollution. Herein, we use hydroxypropyl cellulose (HPC) as a binder to produce gallate-based MOFs pellets. The crystal structure of the well-shaped materials after molding remained intact, and the surface area of the materials hardly decreases after shaping. Adsorption isotherms of C 2 hydrocarbons including ethylene, ethane and acetylene on the activated powders and pellets of M-gallate were recorded and compared with the outperformers. The shaped pellets were also examined by breakthrough experiments on the fixed-bed separation of C 2 H 2 /C 2 H 4 (1:99, v/v) and C 2 H 4 /C 2 H 6 (50:50, v/v) gas mixtures. These results proved that M-gallate pellets was promising candidates for the practical industrial realization of C 2 hydrocarbons separation. [ABSTRACT FROM AUTHOR]