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Biomanufacturing of ethylene is particularly important for modern society. Cyanobacterial cells are able to photosynthesize various valuable chemicals. A promising platform for next‐generation biomanufacturing, the semiconductor‐cyanobacterial hybrid systems are capable of enhancing the solar‐to‐chemical conversion efficiency. Herein, the native ethylene‐producing capability of a filamentous cyanobacterium Nostoc sphaeroides is confirmed experimentally. The self‐assembly characteristic of N. sphaeroides is exploited to facilitate its interaction with InP nanomaterial, and the resulting biohybrid system gave rise to further elevated photosynthetic ethylene production. Based on chlorophyll fluorescence measurement and metabolic analysis, the InP nanomaterial‐augmented photosystem I activity and enhanced ethylene production metabolism of biohybrid cells are confirmed, the mechanism underlying the material‐cell energy transduction as well as nanomaterial‐modulated photosynthetic light and dark reactions are established. This work not only demonstrates the potential application of semiconductor‐N. sphaeroides biohybrid system as a good platform for sustainable ethylene production but also provides an important reference for future studies to construct and optimize nano‐cell biohybrid systems for efficient solar‐driven valuable chemical production. [ABSTRACT FROM AUTHOR]

Efficient separation of acetylene (C2H2)/ethylene (C2H4) and acetylene/carbon dioxide (CO2) by adsorption is an industrially promising process, but adsorbents capable of simultaneously capturing trace acetylene from ethylene and carbon dioxide are scarce. Herein, a gate‐opening effect on three isomorphous flexible metal–organic frameworks (MOFs) named Co(4‐DPDS)2MO4 (M = Cr, Mo, W; 4‐DPDS = 4,4‐dipyridyldisulfide) is modulated by anion pillars substitution. The shortest CrO42− strengthens intraframework hydrogen bonding and thus blocks structural transformation after activation, striking a good balance among working capacity, separation selectivity, and trace impurity removal of flexible MOFs out of nearly C2H2/C2H4 and C2H2/CO2 molecular sieving. The exceptional separation performance of Co(4‐DPDS)2CrO4 is confirmed by dynamic breakthrough experiments. It reveals the specific threshold pressures control in anion‐pillared flexible materials enabled elimination of the impurity leakage to realize high purity products through precise control of the intraframework interaction. The adsorption mechanism and multimode structural transformation property are revealed by both calculations and crystallography studies. This work demonstrates the feasibility of modulating flexibility for controlling gate‐opening effect, especially for some cases of significant aperture shrinkage after activation. [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]

Purification of C2H4 from an C2H4/C2H6 mixture, one of the most important while challenging industrial separation processes, is mainly through energy‐intensive cryogenic distillation. Now a family of gallate‐based metal–organic framework (MOF) materials is presented, M‐gallate (M=Ni, Mg, Co), featuring 3D interconnected zigzag channels, the aperture sizes of which (3.47–3.69 Å) are ideally suitable for molecular sieving of ethylene (3.28×4.18×4.84 Å3) and ethane (3.81×4.08×4.82 Å3) through molecular cross‐section size differentiation. Co‐gallate shows an unprecedented IAST selectivity of 52 for C2H4 over C2H6 with a C2H4 uptake of 3.37 mmol g−1 at 298 K and 1 bar, outperforming the state‐of‐the‐art MOF material NOTT‐300. Direct breakthrough experiments with equimolar C2H4/C2H6 mixtures confirmed that M‐gallate is highly selective for ethylene. The adsorption structure and mechanism of ethylene in the M‐gallate was further studied through neutron diffraction experiments. Purification of C2H4 from an C2H4/C2H6 mixture using a family of gallate‐based metal–organic framework (MOF) materials is presented. M‐gallate (M=Ni, Mg, Co), features 3D interconnected zigzag channels, the aperture sizes of which are ideal for molecular sieving of ethylene and ethane through molecular cross‐section size differentiation. [ABSTRACT FROM AUTHOR]

Ionic liquid (IL) supported metal-organic framework (MOF) was utilized to efficiently separate acetylene from ethylene. A common IL, 1-butyl-3-methylimidazolium acetate ([Bmim][OAc]), was encapsulated into a hydrothermally stable MOF, namely MIL-101(Cr). Characterization techniques including FTIR, Powder X-ray diffraction, BET, and thermal gravimetric analysis were used to confirm successful encapsulation of the IL within MIL-101(Cr). Adsorption isotherms of acetylene and ethylene in the IL-encapsulated MOF were tested. From the results, the MOF composite retained a relatively high adsorption capacity. Remarkably, the adsorption selectivity of acetylene/ethylene has dramatically increased from 3.0 to 30 in comparison with the parent MIL-101(Cr). Furthermore, the potential of industrial practice was examined by breakthrough and regeneration experiments. It not only satisfies the industrial production of removal of low level of acetylene from ethylene, but also is notably stable during the adsorption-desorption process. The high designability of ILs combined with richness of MOFs' structures exploits a novel blueprint for gas separation. © 2016 American Institute of Chemical Engineers AIChE J, 63: 2165-2175, 2017 [ABSTRACT FROM AUTHOR]

Cover Feature: Adsorptive Separation of Acetylene from Ethylene in Isostructural Gallate-Based Metal-Organic Frameworks (Chem. Eur. J. 68/2019) B An isostructural family of M-gallate (M=Mg, Co, Ni) MOFs b not only afforded excellent separation performances for the removal of C SB 2 sb H SB 2 sb from C SB 2 sb H SB 4 sb , but also a remarkably high C SB 2 sb H SB 4 sb productivity of 85.6 mol L SP -1 sp from an 1/99 C SB 2 sb H SB 2 sb /C SB 2 sb H SB 4 sb mixture. Metal-ion substitution, with different lengths of the metal-oxygen bonds, significantly enhanced the interaction between the C SB 2 sb H SB 2 sb molecules and frameworks as a result of precisely controlling the pore aperture size from 3.69 to 3.47 Å. More information can be found in the Full Paper by Z. Bao, Q. Ren, et al. on page 15516. [Extracted from the article]

Highlights • Shaping of anion-pillared ultramicroporous MOFs into pellets with polyvinyl butyral binder. • The loading of MOFs in the pellets were as high as 95%. • Uptake capacity of C 2 H 2 is hardly influenced and the C 2 H 2 /C 2 H 4 selectivity is increased after granulation. • SO 2 uptake of SIFSIX-3-Ni and GeFSIX-2-Cu-i pellets at 2000 ppm were reported for first time. • Pelletization with PVB binder is available for other prototypical MOFs (HKUST-1, Mg-MOF-74 and MIL-101-Cr). Abstract Four anion-pillared ultramicroporous powder (SIFSIX-3-Ni, SIFSIX-2-Cu-i, GEFSIX-2-Cu-i, TIFSIX-2-Cu-i) were shaped into pellets for the first time, using a strongly anti-tearing and highly sticky binder—polyvinyl butyral (PVB). PVB binder exhibited good compatibility and interaction with MOFs, which afforded the ultrahigh-loading of MOFs (up to 95%). Interestingly, this shaping method showed slight influence to the adsorption capacity of C 2 H 2 (decreased by 0.56%–0.93%), while greatly hindered the adsorption of C 2 H 4 (decreased by 5.0%–12.5%). These different influences resulted in the enhanced IAST selectivity (116.4) of GeFSIX-2-Cu-i pellet for the separation of C 2 H 2 /C 2 H 4 (1:99, v/v), which was 35% larger than the pure GeFSIX-2-Cu-i powder (86.3). Fixed-bed breakthrough experiments showed that SIFSIX-3-Ni pellets achieved the effective separation of C 2 H 2 /C 2 H 4 (1:99, v/v) mixtures. Furthermore, SO 2 adsorption of SIFSIX-3-Ni pellets and GeFSIX-2-Cu-i pellets were obtained at 2000 ppm and 298 K. Remarkably, GeFSIX-2-Cu-i pellet had an excellent capacity of SO 2 (95%-loading: 2.25 mmol g−1; 90%-loading: 1.96 mmol g−1) at such a low pressure. Additionally, this approach was applied to other three typical MOFs HKUST-1, Mg-MOF-74, and MIL-101-Cr for CO 2 capture. It revealed that the PVB binder was applicable to diverse MOFs for pelletization. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • TIFSIX-2-Ni-i (ZU-12-Ni) has been synthesized for the first time. • TIFSIX-2-Ni-i exhibits excellent thermal and moisture stability. • TIFSIX-2-Ni-i displays prominent C 2 H 2 capture ability and effective separations. • Excellent cycling stability indicates great potential in industrial separations. • The exquisite control provides a powerful strategy to design new porous materials. Abstract A thermostable anion-pillared metal-organic framework TIFSIX-2-Ni-i (also referred to as ZU-12-Ni, TIFSIX = hexafluorotitanate, 2 = 4,4′-bipyridylacetylene, i = interpenetrated) has been synthesized for the first time. Structural characterizations show that TIFSIX-2-Ni-i exhibits a 2-fold interpenetrated network with narrow aperture of 5.1 Å (H-H distance) and abundant inorganic anion sites in the channel. The subtle change in metal and inorganic linkers results in the enhancement of the thermal stability of TIFSIX-2-Ni-i. Importantly, TIFSIX-2-Ni-i shows high-performing separation properties, especially for the important separations of C 2 H 2 /C 2 H 4 and C 2 H 2 /CO 2 mixtures. Adsorption data demonstrate that TIFSIX-2-Ni-i enables effective C 2 H 2 capture (4.21 mmol/g, at 298 K and 1 bar), and achieves highly selective separation of C 2 H 2 over C 2 H 4 or CO 2 with the IAST selectivity of 22.7 (C 2 H 2 /C 2 H 4 : 1/99) and 10.0 (C 2 H 2 /CO 2 : 2/1) at 298 K and 1 bar. Dispersion-corrected density functional theory (DFT-D) calculations confirm the preferential adsorption of C 2 H 2 over C 2 H 4 and CO 2. Furthermore, the potential of industrial feasibility of TIFSIX-2-Ni-i for C 2 H 2 /C 2 H 4 separation is confirmed by transient breakthrough tests (611.4 mmol/L C 2 H 2 absorbed for mixtures containing 1% C 2 H 2). The excellent cycle performance and stable structure of TIFSIX-2-Ni-i during multiple breakthrough tests show great potential in industrial separation of light hydrocarbons. [ABSTRACT FROM AUTHOR]

• The 4-bed vacuum swing adsorption (VSA) process has been established for ethylene/ethane separation. • The Co-gallate pellets adsorbent exhibits superior VSA process performance compared with zeolite 4A and Ag+-Amberlyst 35. • Ethylene purity of 99.90% was obtained with a productivity of 1.05 mol kg−1 per cycle. • A sensitivity analysis was conducted for process optimization. This work reports a vacuum swing adsorption (VSA) process that utilizes Co-gallate pellets to produce high-purity ethylene. The process is tested on two feed streams generated from the pyrolysis of naphtha and steam cracking of ethane, respectively. The VSA cycle consists of four steps: pressurization, adsorption, replacement with ethylene product and blowdown. A cyclic steady state (CSS) is reached for every test condition, verified by checking the profiles of column pressure, gas composition, and solid loading, which remain constant for ten subsequent cycles. Through analysis of the independent decision variables that affect the performance of the 80/20 (v / v) ethylene/ethane mixture separation, we identify desorption pressure and the replacement flowrate to feed flowrate ratio as the most significant factors. By optimizing these variables, we achieve an exceptional purity of 99.90% for ethylene with a 46.45% recovery and a productivity of 1.05 mol kg−1 per cycle. The Co-gallate adsorbent has a high affinity for ethylene and a low diffusion limitation, thus demonstrating superior potential for industrial ethylene/ethane separation compared to zeolite 4A and Ag+-Amberlyst 35. [ABSTRACT FROM AUTHOR]

A magnesium-based metal-organic framework with high hydrothermal stability, Mg-CUK-1, was investigated for the adsorption separation of acetylene from ethylene. The synthesized MOF remained excellent thermostability even near 500 °C according to TGA results. Characterization techniques including FTIR, SEM, and PXRD were utilized to confirm the detailed structure and properties of the Mg-based MOF. It exhibited moderate adsorption capacities of C 2 H 2 (3.01 mmol/g at 100 kPa and 273 K). Moreover, it showed preferential adsorption of C 2 H 2 over C 2 H 4 with C 2 H 2 /C 2 H 4 adsorption selectivity over 3, outperforming some popular MOFs. Furthermore, the isosteric heat of C 2 H 2 (<21 kJ/mol) and C 2 H 4 (<18 kJ/mol) were extremely lower than those MOFs with open metal sites. From an industrial point of view, this MOF could be synthesized in absence of organic solvent, drastically reducing the risk of environmental pollution in the production process. Besides, such advantages as excellent hydrothermal stability, cheap and non-poisonous metal ion resource, high C 2 H 2 adsorption capacity, and low isosteric heat make the Mg-based MOF promising in practical application. [ABSTRACT FROM AUTHOR]

[Display omitted] • MOF-841 is strongly hydrophobic and highly hydrothermally stable. • MOF-841 shows excellent ethane-selective adsorption performance with high C 2 H 6 uptake capacity. • The synergistic effects rooting in C-H∙∙∙π and C-H···O interactions ensure the strong affinity for C 2 H 6. The removal of ethane (C 2 H 6) from ethylene (C 2 H 4) is of great importance to afford polymer-grade C 2 H 4 with purity greater than 99.95% as feedstock to produce polyethylene. Adsorptive separation with C 2 H 6 -selective metal-organic frameworks (MOFs) can directly produce high-purity C 2 H 4 , which has shown bright prospects for replacing the energy-intensive cryogenic distillation. Herein, we demonstrate a robust zirconium MOF possessing hydrophobic pores and oxygen-rich groups, namely MOF-841, can preferentially adsorb C 2 H 6 over C 2 H 4. Experimental adsorption isotherms and breakthrough show high separation performance for the gas mixture of C 2 H 6 and C 2 H 4 due to ultrahigh C 2 H 6 uptake capacity (4.7 mmol/g) and distinctive C 2 H 6 /C 2 H 4 uptake ratio (1.35) of MOF-841 at 298 K and 100 kPa. Computational studies reveal that aromatic rings and carboxylate oxygen atoms pointing towards the pore ascribed to trapping C 2 H 6 through synergistic effects arising from multiple van der Waals interactions including C-H∙∙∙π and C-H···O, which are more potent than C 2 H 4 -framework interactions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Highly CO2-soluble ethylene oxide diphosphates were designed and synthesized. [•] Solubility data for these compounds were determined and correlated by Bartle model. [•] Structure effects on solubility were discussed through COSMO-RS method. [•] Branched side chain played an important role in the enhancement of solubility. [ABSTRACT FROM AUTHOR]

As environmentally friendly and designablesolvents, ionic liquids (ILs) have great potential in the separationof C2H4and C2H2, whichis quite important in chemical industry. The microscopic insight intothe intermolecular interaction and the diffusion dynamics at a molecularlevel is crucial for designing more efficient ILs. In this work, theinteraction mechanism and diffusion dynamics for C2H4/C2H2absorption and separation withfive ILs, 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]), 1-butyl-3-methylimidazolium acetate ([bmim][OAc]), 1-butyl-3-methylimidazoliumtrifluoroacetate ([bmim][TFA]), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([bmim][Tf2N]), and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide([bmpyrr][Tf2N]), were investigated by molecular dynamics(MD) simulation. The result suggests that the van der Waals interactionbetween C2H4and cation plays an important rolein C2H4dissolution in ILs, but the hydrogenbonding interaction between C2H2and anion isforemost in C2H2dissolution. Moreover, theinteraction energy analysis matches better with the experimental solubilitythan our previous quantum chemical calculation, indicating the superiorityof the MD simulation approach in studying the interaction mechanismof IL-based systems where multiple interactions are often present.The self-diffusion coefficients of cations and anions of ILs do notchange obviously after adding C2H4, while theyhave a significant increase after dissolving C2H2, particularly in relatively strong hydrogen bonding systems [bmim][OAc]–C2H2. [ABSTRACT FROM AUTHOR]