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Comprehensive Summary: Carbon dioxide (CO2) capture is one of the most important aspects of reducing global warming. In terms of CO2 capture, metal‐organic frameworks (MOFs) have several advantages. However, it isn't easy to shape MOFs while maintaining their performance. Herein, we describe the development of a pellet‐shaped ultramicroporous MOF, Ni(3‐ain)2 (3‐ain = 3‐aminoinoisonicotinic acid), that is capable of selectively adsorbing CO2. Polyvinyl butyral (PVB) is used as a binder during the production of Ni(3‐ain)2 MOF pellets. The adequately shaped material can maintain its crystallinity and exhibit a high CO2 adsorption capacity (3.73 mmol·g–1) at ambient conditions, which is significantly greater than those obtained for N2 (0.63 mmol·g–1) and CO (0.90 mmol·g–1). Consequently, this material displays high IAST selectivities for CO2/N2 (26.3, 15/85, V/V) and CO2/CO (19.2, 1/99, V/V). According to the theoretical calculations, Ni(3‐ain)2 preferentially adsorbs CO2 molecules over N2 molecules and CO molecules. The results of experiments on dynamic breakthrough have demonstrated that Ni(3‐ain)2 pellets are capable of effectively separating CO2/N2 or CO2/CO mixtures under conditions of dynamic flow. Furthermore, the structured MOF materials can be synthesized in one step at kilogram scale. This work provides an avenue for the shaping of MOFs for potential industrial applications in the future. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Carbon dioxide (CO2) capture is one of the most important aspects of reducing global warming. In terms of CO2 capture, metal‐organic frameworks (MOFs) have several advantages. However, it isn't easy to shape MOFs while maintaining their performance. Herein, we describe the development of a pellet‐shaped ultramicroporous MOF, Ni(3‐ain)2 (3‐ain = 3‐aminoinoisonicotinic acid), that is capable of selectively adsorbing CO2. Polyvinyl butyral (PVB) is used as a binder during the production of Ni(3‐ain)2 MOF pellets. The adequately shaped material can maintain its crystallinity and exhibit a high CO2 adsorption capacity (3.73 mmol·g–1) at ambient conditions, which is significantly greater than those obtained for N2 (0.63 mmol·g–1) and CO (0.90 mmol·g–1). Consequently, this material displays high IAST selectivities for CO2/N2 (26.3, 15/85, V/V) and CO2/CO (19.2, 1/99, V/V). According to the theoretical calculations, Ni(3‐ain)2 preferentially adsorbs CO2 molecules over N2 molecules and CO molecules. The results of experiments on dynamic breakthrough have demonstrated that Ni(3‐ain)2 pellets are capable of effectively separating CO2/N2 or CO2/CO mixtures under conditions of dynamic flow. Furthermore, the structured MOF materials can be synthesized in one step at kilogram scale. This work provides an avenue for the shaping of MOFs for potential industrial applications in the future. [ABSTRACT FROM AUTHOR]

In order to study the effects of different storage temperatures and preservatives on the preservation effects of Qiuyang pear fruits, the effects of 0.5 μL/L 1 -methylcyclopropene (1 -MCP) fumigation for 12 h and ethylene adsorbent treatments on the storage qualities of Qiuyang pears were investigated under different storage temperatures (-1 °C and 0 °C). The results showed that after 120 days of storage, the decay rates of fruits stored at 0°C was lower than that stored at -1°C under the same treatment conditions. At 270 days, the decay rates of fruits stored at 0 °C and -1°C in the two preservatives treatment groups were lower than those in CK group. The fruits peels brightness of CK group and ethylene sorbent treatment group at 0°C was higher than that stored at -1 °C. After 240 days of storage, the fruits hardness of 1-MCP treatment group was remarkably higher than that of other treatments groups (P<0.05), and the fruits hardness of 1-MCP treatment group stored at 0°C was significantly higher than that stored at -1°C at 270 days (P<0.05). The titratable acid contents of fruits in the two preservatives treatment groups were higher than that in CK group at 270 days of storage. The soluble solids contents of fruits in each group presented no significant changes during storage. In conclusion, Qiuyang pears presented low decay rates and well maintained peels brightness when stored at 0°C. The two preservatives treatments could both reduce the decay rates and delay the decline of titratable acid contents of Qiuyang pears, and the 1-MCP treatment showed better effects that could effectively maintain peel brightness and fruit firmness. [ABSTRACT FROM AUTHOR]

In the electronics industry, the efficient recovery and capture of sulfur hexafluoride (SF6) from SF6/N2 mixtures is of great importance. Herein, three metal–organic frameworks with fine‐tuning pore structures, Cu(peba)2, Ni(pba)2, and Ni(ina)2, were designed for SF6 capture. Among them, Ni(ina)2 has perfect pore sizes (6 Å) that are comparable to the kinetic diameter of sulfur hexafluoride (5.2 Å), affording the benchmark binding affinity for SF6 gas. Ni(ina)2 exhibits the highest SF6/N2 selectivity (375.1 at 298 K and 1 bar) and ultra‐high SF6 uptake capacity (53.5 cm3 g−1 at 298 K and 0.1 bar) at ambient conditions. The remarkable separation performance of Ni(ina)2 was verified by dynamic breakthrough experiments. Theoretical calculations and the SF6‐loaded single‐crystal structure provided critical insight into the adsorption/separation mechanism. This porous coordination network has the potential to be used in industrial applications. [ABSTRACT FROM AUTHOR]

The enrichment and purification of coal‐bed methane provides a source of energy and helps offset global warming. In this work, we demonstrate a strategy involving the regulation of the pore size and pore chemistry to promote the separation of CH4/N2 mixtures in four nickel‐based coordination networks, named Ni(ina)2, Ni(3‐ain)2, Ni(2‐ain)2, and Ni(pba)2, (where ina=isonicotinic acid, 3‐ain=3‐aminoisonicotinic acid, 2‐ain=2‐aminoisonicotinic acid, and pba=4‐(4‐pyridyl)benzoic acid). Among them, Ni(ina)2 and Ni(3‐ain)2 can effectively separate CH4 from N2 with top‐performing performance because of the suitable pore size (≈0.6 and 0.5 nm) and pore environment. Explicitly, Ni(ina)2 exhibits the highest ever reported CH4/N2 selectivity of 15.8 and excellent CH4 uptake (40.8 cm3 g−1) at ambient conditions, thus setting new benchmarks for all reported MOFs and traditional adsorbents. The exceptional CH4/N2 separation performance of Ni(ina)2 is confirmed by dynamic breakthrough experiments. Under different CH4/N2 ratios, Ni(ina)2 selectively extracts methane from the gaseous blend and produces a high purity of CH4 (99 %). Theoretical calculations and CH4‐loading single‐crystal structure analysis provide critical insight into the adsorption/separation mechanism. Ni(ina)2 and Ni(3‐ain)2 can form rich intermolecular interactions with methane, indicating a strong adsorption affinity between pore walls and CH4 molecules. Importantly, Ni(ina)2 has good thermal and moisture stability and can easily be scaled up at a low cost ($25 per kilogram), which will be valuable for potential industrial applications. Overall, this work provides a powerful approach for the selective adsorption of CH4 from coal‐bed methane. [ABSTRACT FROM AUTHOR]