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![a) Distribution of simulated selectivities for experimentally synthesized (green) and hypothetical (yellow) MOF structures out of ≈125 000 MOF compounds; vertical, dashed line is SBMOF-1. b) Histogram showing relationship between selectivity and pore size, with the largest included sphere diameter as a metric. c) Crystal structure of SBMOF-1. d) Calculated potential energy contours of an Xe atom adsorbed in the pore (blue surface, −32 kJ mol −1 ; white surface, 15 kJ mol −1 ). Reproduced with permission. [162] Copyright 2016 Macmillan Publishers Ltd.](profile/Wang-Yanxiang/publication/324041780/figure/fig5/AS:636108224331776@1528671427982/a-Distribution-of-simulated-selectivities-for-experimentally-synthesized-green-and.png)
a) Distribution of simulated selectivities for experimentally synthesized (green) and hypothetical (yellow) MOF structures out of ≈125 000 MOF compounds; vertical, dashed line is SBMOF-1. b) Histogram showing relationship between selectivity and pore size, with the largest included sphere diameter as a metric. c) Crystal structure of SBMOF-1. d) Calculated potential energy contours of an Xe atom adsorbed in the pore (blue surface, −32 kJ mol −1 ; white surface, 15 kJ mol −1 ). Reproduced with permission. [162] Copyright 2016 Macmillan Publishers Ltd.
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Separation is an important industrial step with critical roles in the chemical, petrochemical, pharmaceutical, and nuclear industries, as well as in many other fields. Although much progress has been made, the development of better separation technologies, especially through the discovery of high‐performance separation materials, continues to attra...
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... Banerjee et al. also performed a high-throughput computational screening on ≈5000 existing MOF structures and ≈120 000 hypothetical MOFs to predict their Xe/Kr selec- tivity (Figure 8a,b). [162] According to their calculation, SBMOF-1 exhibits the highest thermodynamic selectivity of ≈70.6 among all existing MOFs. Note that the above selectivity was calcu- lated using the ratio of Henry's coefficient, which is feasible at dilute conditions relevant to UNF reprocessing off-gas. SBMOF-1 (also known as CaSDB, SDB = 4,4-sulfonyldiben- zoate) is a calcium-based MOF originally synthesized for CO 2 / N 2 separation (Figure 8c,d). [163] The separation performance of SBMOF-1 was tested through both single component equilib- rium and kinetic adsorption experiment and column break- through experiment. The pure component adsorption of Xe and Kr revealed that SBMOF-1 exhibits much higher Xe Henry coefficient than all top performing MOF materials prior to this work, which is actually a factor of two higher than CC3, a previ- ously reported material with the second highest Xe Henry coef- ficient. [164] Its thermodynamic Xe/Kr selectivity (≈16) also tops all MOFs to date, though it is much lower than the predicted value. The authors further used a gas mixture that mimics the composition of UNF reprocessing off-gas (400 ppm Xe, 40 ppm Kr, 78.1% N 2 , 20.95 O 2 , 0.03% CO 2 , and 0.9% Ar) to conduct a single column breakthrough experiment. The result showed that Xe was retained in the column for more than an hour while all other gases broke through within minutes. The capacity of adsorbed Xe (13.2 mmol Xe per kg) is superior to that of benchmark materials such as Ni-MOF-74 (4.8 mmol Xe per kg) and CC3 (11 mmol Xe per kg). Similar capacity can be obtained even in the presence of moisture. SBMOF-1 has a pore size of ≈4.2 Å, slightly larger than an Xe atom, ≈4.1 Å. It was found that such a pore diameter is a prerequisite for a highly Xe-selective material, as the pore size controls the prox- imity and degree of overlap from multiple framework atoms contributing van der Waals interactions from multiple direc- tions to achieve a highly favorable host-Xe interaction. A pore of optimal size for Xe is suboptimal for Kr so this forms a pore that is highly discriminatory for Xe over ...
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... Banerjee et al. also performed a high-throughput computational screening on ≈5000 existing MOF structures and ≈120 000 hypothetical MOFs to predict their Xe/Kr selec- tivity (Figure 8a,b). [162] According to their calculation, SBMOF-1 exhibits the highest thermodynamic selectivity of ≈70.6 among all existing MOFs. Note that the above selectivity was calcu- lated using the ratio of Henry's coefficient, which is feasible at dilute conditions relevant to UNF reprocessing off-gas. SBMOF-1 (also known as CaSDB, SDB = 4,4-sulfonyldiben- zoate) is a calcium-based MOF originally synthesized for CO 2 / N 2 separation (Figure 8c,d). [163] The separation performance of SBMOF-1 was tested through both single component equilib- rium and kinetic adsorption experiment and column break- through experiment. The pure component adsorption of Xe and Kr revealed that SBMOF-1 exhibits much higher Xe Henry coefficient than all top performing MOF materials prior to this work, which is actually a factor of two higher than CC3, a previ- ously reported material with the second highest Xe Henry coef- ficient. [164] Its thermodynamic Xe/Kr selectivity (≈16) also tops all MOFs to date, though it is much lower than the predicted value. The authors further used a gas mixture that mimics the composition of UNF reprocessing off-gas (400 ppm Xe, 40 ppm Kr, 78.1% N 2 , 20.95 O 2 , 0.03% CO 2 , and 0.9% Ar) to conduct a single column breakthrough experiment. The result showed that Xe was retained in the column for more than an hour while all other gases broke through within minutes. The capacity of adsorbed Xe (13.2 mmol Xe per kg) is superior to that of benchmark materials such as Ni-MOF-74 (4.8 mmol Xe per kg) and CC3 (11 mmol Xe per kg). Similar capacity can be obtained even in the presence of moisture. SBMOF-1 has a pore size of ≈4.2 Å, slightly larger than an Xe atom, ≈4.1 Å. It was found that such a pore diameter is a prerequisite for a highly Xe-selective material, as the pore size controls the prox- imity and degree of overlap from multiple framework atoms contributing van der Waals interactions from multiple direc- tions to achieve a highly favorable host-Xe interaction. A pore of optimal size for Xe is suboptimal for Kr so this forms a pore that is highly discriminatory for Xe over ...
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... Banerjee et al. also performed a high-throughput computational screening on ≈5000 existing MOF structures and ≈120 000 hypothetical MOFs to predict their Xe/Kr selec- tivity (Figure 8a,b). [162] According to their calculation, SBMOF-1 exhibits the highest thermodynamic selectivity of ≈70.6 among all existing MOFs. ...
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... that the above selectivity was calcu- lated using the ratio of Henry's coefficient, which is feasible at dilute conditions relevant to UNF reprocessing off-gas. SBMOF-1 (also known as CaSDB, SDB = 4,4-sulfonyldiben- zoate) is a calcium-based MOF originally synthesized for CO 2 / N 2 separation (Figure 8c,d). [163] The separation performance of SBMOF-1 was tested through both single component equilib- rium and kinetic adsorption experiment and column break- through experiment. ...
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... The primary method for generating high-purity light alkenes essential for polymers-specifically, ethylene and propylene at 99.5 % purit-is through cryogenic distillation of steam cracking gas. This process ranks among the most energy-intensive procedures in the chemical industry, contributing to a production energy consumption that represents 0.3 % of global energy [6][7][8][9]. Hence, there has been significant attention on adsorption separation methods utilizing porous materials in recent years. ...
Simultaneously capturing and separating high-purity C 2 H 4 and C 3 H 6 from cracked gas mixtures presents a significant challenge. Herein, a robust metal-organic framework (Cu(BF 4) 2 (4-DPDS) 2) was designed featuring a gourd-shaped one-dimensional channel. Its specific alkenes match structure can only adsorb alkenes while completely excluding alkanes. With a remarkable adsorption selectivity of 76,203 for equimolar C 2 H 4 /C 2 H 6 and high selectivity of 159 for equimolar C 3 H 6 /C 3 H 8 , Cu(BF 4) 2 (4-DPDS) 2 not only achieves >99 % purity separation of C 2 H 4 and C 3 H 6 from binary mixtures but also simultaneously captures and separates these compounds from seven-component cracking gases at ambient conditions. Its performance stability remains intact even under 75 % RH conditions, thanks to its robust framework. Based on the particular gourd-shaped channel, it can also achieve efficient C 2 H 2 /CO 2 separation. Ab initio Molecular Dynamics simulations demonstrate the dynamic diffusion process of gas molecules in the structure, and in situ infrared analyses reveal the framework's rich C-H•••F and S•••π binding sites with C 2 H 4 and C 3 H 6. This material's robust structure, exceptional alkene sieving capabilities, and repeatable separation performance comprehensively showcase Cu(BF 4) 2 (4-DPDS) 2 as a unique metal-organic framework for simultaneous recognition and capture of C 2 H 4 and C 3 H 6 .
... MOFs exhibit unique properties that make them desirable substrates for fabricating chromatographic columns, including high porosity, large surface area, and well-defined, homogenous pores. MOFs have become popular in research as they exhibit unprecedented structural designability and diversity [4][5][6]. ...
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... Metal-organic frameworks (MOFs) have emerged as promising materials for addressing this challenge. These porous materials, composed of organic ligands and metal nodes, offer a versatile platform for various applications, including gas adsorption [3][4][5][6], separation [1,7,8], catalysis [9][10][11], delivery of drugs [12][13][14], sensing [15][16][17], batteries [18][19][20][21]. Their stable framework structure, high surface area, large porosity, and tunable pore size make them particularly attractive for gas adsorption and separation tasks [22][23][24]. ...
In response to the challenging task of effecting CO2 and N2 adsorption separation under humid gas conditions, this study employs a methodology that integrates molecular simulation with high-throughput screening. The focus is on investigating the adsorption separation of a ternary mixture (CO2/N2/H2O) utilizing the most recent experimental synthesis of metal–organic frameworks (MOFs) from the CoRE-MOF-2019 database. To circumvent the competitive adsorption of water vapor, materials with excessive hydrophilicity are systematically excluded. Subsequently, a univariate analysis is conducted on the remaining 1343 MOFs, exploring the intricate relationships between key structural parameters such as pore limiting diameter, maximum pore cavity diameter of free channels (LCD), pore volume (Vpore), volume surface area (VSA), weight surface area, density (ρ), porosity (φ), Henry coefficient (K), adsorption heat (Qst0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$Q_{{{\text{st}}}}^{0}$$\end{document}), and metal types. The investigation reveals positive correlations between ρ, K, and Qst0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$Q_{{{\text{st}}}}^{0}$$\end{document} with selectivity, while other descriptors exhibit negative correlations. Notably, MOFs enriched with Cd and Cu demonstrate superior performance. Subsequent analysis employs Pearson coefficients and a decision tree model to rank descriptors and identify the top three descriptors (LCD, VSA, and Qst0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$Q_{{{\text{st}}}}^{0}$$\end{document}) influencing performance. Utilizing these descriptors, the decision tree model delineates optimal design criteria: Qst0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$Q_{{{\text{st}}}}^{0}$$\end{document} > 28.296 kJ mol⁻¹, LCD < 5.893 Å, and VSA > 727.596 m² cm⁻³. To predict the performance of MOFs that have not yet been synthesized or experimentally validated, we employed the nine descriptors for model training and out-of-sample validation. The decision tree classifier exhibits high prediction accuracy and shows excellent transferability, effectively delineating the boundaries between different performance classes by capturing structural–selectivity correlations. This process culminates in the screening of 15 optimal MOFs, offering theoretical insights for the adsorption separation of CO2 in humid flue gas.
... Metal-organic frameworks (MOFs) represent a category of porous crystalline materials consisting of metal ions or clusters linked by organic ligands [28][29][30]. These MOFs have garnered significant a ention for diverse applications, including gas storage [31][32][33], separation [34][35][36], catalysis [37], and sensing [38][39][40], owing to their notable features, such as high surface area, adjustable pore size, and versatile functionality [41][42][43]. Additionally, MOFs can function as templates or precursors for synthesizing other nanostructures, such as metal oxides, sulfides, and carbons, through processes such as thermal decomposition [44], sulfidation [45], or carbonization [46,47]. ...
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... 124 Since the pore size of MOFs can be precisely modified, they have better antifouling performance, high permeability, and selectivity for removal of a variety of pollutants in wastewater. 125 Although the adsorption mechanism of MOFs for the removal of pollutants is complicated, researchers explain these mechanisms using H-bonding, electrostatic interactions, ion exchange, and interactions. 126 Surface charges on adsorbates (pollutants) and oppositely charged adsorbents (MOFs) interact electrostatically during adsorption processes. ...
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... Selective adsorption using porous materials has been deemed an energy-efficient technology for hydrocarbon separation 9,10 ; however, for hydrocarbons with the same carbon chain length, the alkyne and the corresponding alkene differ by just two hydrogen atoms, and their separation efficiency hinges largely on precise control over the pore structures and sizes of the porous materials. In this regard, metal-organic frameworks (MOFs), also known as porous coordination polymers, stand out because of their tailor-made pore dimensions and surface chemistry, due to the versatility of their building blocks and the variety of connection modes [11][12][13][14][15][16] . MOF materials have been studied extensively as adsorbents for alkyne/alkene separations [17][18][19][20] . ...
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Although Zr-based metal–organic frameworks (MOFs) exhibit robust chemical and physical stability in the presence of moisture and acidic conditions, their susceptibility to nucleophilic attacks from bases poses a critical challenge to their overall stability. Herein, we systematically investigate the stability of Zr-based UiO-66 (UiO = University of Oslo) MOFs in basic solutions. The impact of 11 standard bases, including inorganic salts and organic bases, on the stability of these MOFs is examined. The destruction of the framework is confirmed through powder X-ray diffraction (PXRD) patterns, and the monitored dissolution of ligands from the framework is assessed using nuclear magnetic resonance (NMR) spectroscopy. Our key findings reveal a direct correlation between the strength and concentration of the base and the destruction of the MOFs. The summarized data provide valuable insights that can guide the practical application of Zr-based UiO-66 MOFs under basic conditions, offering essential information for their optimal utilization in various settings.
