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1.
J Colloid Interface Sci ; 581(Pt A): 177-184, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32771729

RESUMO

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 C2 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 C2 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 C2H2/C2H4 (1:99, v/v) and C2H4/C2H6 (50:50, v/v) gas mixtures. These results proved that M-gallate pellets was promising candidates for the practical industrial realization of C2 hydrocarbons separation.

2.
J Chromatogr A ; 1624: 461264, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32540086

RESUMO

Gas-liquid chromatography is an effective method to determine infinite dilution activity coefficients (γ∞). Wall-coated open-tubular (WCOT) column which offers more advantages over packed column should be a preferable column type; however, the small carrier gas flow rate and stationary phase amount in WCOT columns limit its application in the determination of γ∞. Mathematical strategy made some progress to avoid the quantification problem in the determination of γ∞ by static-wall-coated open-tubular (SWCOT) columns. However, the previously reported strategy was based on the assumption that SWCOT column was geometrically an ideal hollow cylinder, which indeed deviates from the reality. In this study, without that assumption, we derived a new microgeometry-independent equation by using the relationship between the hold-up volume (VM) and the volume of stationary phase (VL), and used it to measure the γ∞ of various organic solutes in two ionic liquids (ILs) 1­butyl­3-methylimidazolium dicyanamide and 1,3-dibutyronitrile-imidazolium bis((trifluoromethyl)sulfonyl)imide, both of which contain double cyano groups in the anion or cation. Phase loading study was adopted to eliminate the influence of interfacial adsorption to partition. The infinite dilution partial molar excess enthalpy, selectivity and capacity were directly calculated from the experimental γ∞ values, and the linear solvation energy relationship (LSER) model was used to characterize the specific properties of both ILs. This new established equation will promote the application of SWCOT columns in thermodynamic measurement and benefit the fast screening of novel solvents for chemical separation processes.


Assuntos
Cromatografia Gasosa/métodos , Adsorção , Imidazóis/química , Líquidos Iônicos/química , Dióxido de Silício/química , Cloreto de Sódio/química , Soluções , Solventes , Termodinâmica
3.
ACS Appl Mater Interfaces ; 12(20): 23002-23009, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32338862

RESUMO

Multifunctional metal-organic frameworks (MOFs) that possess permanent porosity are promising catalysts in organic transformation. Herein, we report the construction of a hierarchical MOF functionalized with basic aliphatic amine groups and polyvinylpyrrolidone-capped platinum nanoparticles (Pt NPs). The postsynthetic covalent modification of organic ligands increases basic site density in the MOF and simultaneously introduces mesopores to create a hierarchically porous structure. The multifunctional MOF is capable of catalyzing a sequential Knoevenagel condensation-hydrogenation-intramolecular cyclization reaction. The unique selective reduction of the nitro group to intermediate hydroxylamine by Pt NPs supported on MOF followed by intramolecular cyclization with a cyano group affords an excellent yield (up to 92%) to the uncommon quinoline N-oxides over quinolines. The hierarchical MOF and polyvinylpyrrolidone capping agent on Pt NPs synergistically facilitate the enrichment of substrates and thus lead to high activity in the reduction-intramolecular cyclization reaction. The bioactivity assay indicates that the synthesized quinoline N-oxides evidently inhibit the proliferation of lung cancer cells. Our findings demonstrate the feasibility of MOF-catalyzed direct synthesis of bioactive molecules from readily available compounds under mild conditions.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32329164

RESUMO

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 C3 H6 and C2 H4 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 C3 H4 /C3 H6 uptake ratios and capacity-enhanced C2 H2 /C2 H4 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 C3 H4 /C3 H6 and C2 H2 /C2 H4 mixtures.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32188243

RESUMO

The simultaneous capture of trace propyne and propadiene from propylene is one of the important but energy demanding industrial processes because of their similar physicochemical properties as well as the ultralow concentration in the mixtures. Herein, a highly stable Ca-based MOF, constructed from an inexpensive precursor (CaCO3) and rigid squaric acid, is capable of preferentially capturing trace propyne and propadiene with record-high uptake capacities of 2.44 and 2.64 mmol/g at pressures as low as 5 mbar, respectively. Direct multicomponent breakthrough experiments confirm that Ca-based MOF exhibits an excellent performance for simultaneous removal of trace propyne and propadiene from propylene. DFT simulation and in situ single-crystal X-ray diffraction of propadiene- and propyne-adsorbed Ca-based MOFs reveal that the strong affinity of the framework toward two species is ascribed to the multiple types of cooperative binding including π-π stacking and C-H···O interactions. The calcium squarate framework sets a new benchmark for adsorptive purification of propylene, showing great potential in the practical application.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32009387

RESUMO

The separation of mixed C4 olefins is a highly energy-intensive operation in the chemical industry due to the close boiling points of the unsaturated C4 isomers. In particular, the separation of trans/cis-2-butene is among the most challenging separation processes for geometric isomers and is of prime importance to increase the added value of C4 olefins. In this work, we report a series of isostructural gallate-based metal-organic frameworks (MOFs), namely, M-gallate (M = Ni, Mg, Co), featuring oval-shaped pores, that are ideally suitable for shape-selective separation of trans/cis-2-butene through their differentiation in minimum molecular cross-section size. Significantly, Mg-gallate displays a record high trans/cis-2-butene uptake selectivity of 3.19 at 298 K, 1.0 bar in single-component adsorption isotherms. These gallate-based MOFs not only exhibit the highest selectivity for trans/cis-2-butene separation but also accomplish a highly efficient separation of 1,3-butadiene, 1-butene, and iso-butene. DFT-D study shows that Mg-gallate interacts strongly with trans-2-butene and 1,3-butadiene along with short distances of C···H-O cooperative supramolecular interaction of 2.57-2.83 and 2.45-2.79 Å, respectively. In breakthrough experiments, Mg-gallate not only displays prominent separation performance for trans/cis-2-butene but also realizes the clean separation of a ternary mixture of 1,3-butadiene/1-butene/iso-butene and a binary mixture of 1-butene/iso-butene. This work indicates that M-gallate are industrially promising materials for adsorption separation of geometric isomers of C4 hydrocarbons.

7.
Angew Chem Int Ed Engl ; 59(9): 3423-3428, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-31746086

RESUMO

The separation of xenon/krypton (Xe/Kr) mixture is of great importance to industry, but the available porous materials allow the adsorption of both, Xe and Kr only with limited selectivity. Herein we report an anion-pillared ultramicroporous material NbOFFIVE-2-Cu-i (ZU-62) with finely tuned pore aperture size and structure flexibility, which for the first time enables an inverse size-sieving effect in separation along with record Xe/Kr selectivity and ultrahigh Xe capacity. Evidenced by single-crystal X-ray diffraction, the rotation of anions and pyridine rings upon contact of larger-size Xe atoms adapts cavities to the shape/size of Xe and allows strong host-Xe interaction, while the smaller-size Kr is excluded. Breakthrough experiments confirmed that ZU-62 has a real practical potential for producing high-purity Kr and Xe from air-separation byproducts, showing record Kr productivity (206 mL g-1 ) and Xe productivity (42 mL g-1 , in desorption) as well as good recyclability.

8.
Chemistry ; 25(68): 15516-15524, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31469453

RESUMO

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 Šby metal replacement. Controlling the aperture size of M-gallate materials slightly from 3.69 down to 3.47 Šcould result in a dramatic enhancement of C2 H2 /C2 H4 separation performance. As the smallest radius among the studied metal ions, Ni-gallate exhibits the best C2 H2 /C2 H4 adsorption separation performance owing to the strongest confinement effect, ranking after the state-of-the-art UTSA-200a with a C2 H4 productivity of 85.6 mol L-1 from 1:99 C2 H2 /C2 H4 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 C2 H2 from C2 H4 .

9.
ACS Appl Mater Interfaces ; 11(31): 28197-28204, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31310714

RESUMO

The pore size of adsorbents plays a vital role in determining the overall separation performance of gas separation and purification by adsorption. In this work, the pore apertures of the coordination pillared layer (CPL) was systematically controlled by adjusting the length of pillared ligands. We used pyrazine, 4,4'-bipyridine, and 1,2-di(4-pyridyl)-ethylene with increased length to synthesize CPL-1 (L = pyrazine), CPL-2 (L = 4,4'-bipyridine), and CPL-5 [L = 1,2-di(4-pyridyl)-ethylene], respectively. The aperture size of these CPLs varies from 4 to 11 Å: CPL-1 (4 × 6 Å2), CPL-2 (9 × 6 Å2), and CPL-5 (11 × 6 Å2). Among the three frameworks, CPL-2 exhibits the highest C2H2 uptake at ambient conditions as it has moderate pore size and porosity. However, CPL-1 has the best separation performance in the breakthrough experiments with binary gas mixture of C2H2/C2H4, thanks to the optimal pore size nearly excluding C2H4, which is only observed in the state-of-the-art UTSA-300a so far. The DFT calculations were carried out to elucidate the specific adsorption sites for both acetylene and ethylene among these frameworks. The modeling results suggest that binding strength is highly related to aperture size and that CPL-1 shows the highest adsorption selectivity owing to the optimal pore size. This work demonstrates that engineering pore size enables us to fabricate the highly efficient metal-organic framework (MOF)-based adsorbents for specific gas separation on the basis of the isoreticular chemistry.

10.
J Am Chem Soc ; 141(23): 9358-9364, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31091084

RESUMO

The efficient separation of xenon (Xe) and krypton (Kr) is one of the industrially important processes. While adsorptive separation of these two species is considered to be an energy efficient process, developing highly selective adsorbent remains challenging. Herein, a rigid squarate-based metal-organic framework (MOF), having a perfect pore size (4.1 Å × 4.3 Å) comparable with the kinetic diameter of Xe (4.047 Å) as well as pore surface decorated with very polar hydroxyl groups, is able to effectively discriminate Xe atoms, affording a record-high Xe/Kr selectivity. An exceptionally high Xe uptake capacity of 58.4 cm3/cm3 and selectivity of 60.6 at low pressure (0.2 bar) are achieved at ambient temperature. The MOF exhibits the highest Xe Henry coefficient (192.1 mmol/g/bar) and Xe/Kr Henry selectivity (54.1) among all state-of-the-art adsorbents reported so far. Direct breakthrough experiments further confirm the excellent separation performance. The density functional theory calculations reveal that the strong interaction between Xe and the framework is a result of the synergy between optimal pore size and polar porosity.

11.
ACS Appl Mater Interfaces ; 11(2): 2543-2550, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30565914

RESUMO

The demand for CO2/C2H2 separation, especially the removal of CO2 impurity, continues to grow because of the high-purity C2H2 required for various industrial applications. The adsorption separation of C2H2 and CO2 via porous materials is gaining a considerable attention as it is more energy-efficient compared with cryogenic distillation. The ideal porous materials are those that preferentially adsorb CO2 over C2H2; however, very few adsorbents meet such requirement. Herein, two isostructural cyclodextrin-based CD-MOFs (CD-MOF-1 and CD-MOF-2) were demonstrated to have an inverse ability to selectively capture CO2 from C2H2 by single-component adsorption isotherms and dynamic breakthrough experiments. These two MOFs showed excellent adsorption capacity and benchmark selectivity (118.7) for CO2/C2H2 mixture at room temperature, enabling the pure C2H2 to be obtained in only one step. This work revealed that these materials were promising adsorbents for obtaining high-purity C2H2 via selectively capturing CO2 from C2H2.

12.
Angew Chem Int Ed Engl ; 57(49): 16020-16025, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30304568

RESUMO

Purification of C2 H4 from an C2 H4 /C2 H6 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 C2 H4 over C2 H6 with a C2 H4 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 C2 H4 /C2 H6 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.

13.
Se Pu ; 36(9): 858-865, 2018 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-30251513

RESUMO

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are important ω -3 polyunsaturated fatty acids. Their physiological effects on humans are not exactly the same; therefore, the production of products with high-purity EPA or DHA monomers is significant. In this work, EPA ethyl ester (EPA-EE) and DHA ethyl ester (DHA-EE) were first separated using HPLC with poly(styrene-co-divinylbenzene) (PS/DVB) as the stationary phase. The effects of the mobile phase, PS/DVB particle diameter, and column temperature were systematically evaluated. The results showed that methanol is a suitable mobile phase, having a resolution of 2.75. By comparing resolutions, a PS/DVB particle diameter of 10 µ m was chosen; however, when the pressure drop of PS/DVB is considered, PS/DVB with a particle diameter of 20 µ m is more favorable for large-scale preparations. A column temperature of 40℃ was found to be the most feasible for maintaining efficient separation. Second, eight semi-preparative columns (150 mm×10 mm) of PS/DVB polymer were prepared for the simulated moving bed (SMB) chromatography; the homogeneity of these columns was perfect, with a relative total column porosity error of less than 1%. Finally, an EPA-EE and DHA-EE mixture was separated using the SMB chromatography, and the contents of the extract and the raffinate were determined using GC-FID. The effects of the flow rate of Zone Ⅱ and Zone Ⅲ, the flow rate of the feed, and the feed concentration were investigated. Under optimal conditions, EPA-EE and DHA-EE with favorable purities of 91.6% and 93.6%, respectively, were achievable. The recovery of the EPA-EE was 97.0% and the recovery of the DHA-EE was 91.6%. The productivity and solvent requirements were 5.97 g/(L\5h) and 1.52 L/g, respectively. Therefore, SMB chromatography is an attractive technology for the production of high-value products.


Assuntos
Ácidos Docosa-Hexaenoicos/isolamento & purificação , Ácido Eicosapentaenoico/análogos & derivados , Ácidos Graxos Ômega-3/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Ácido Eicosapentaenoico/isolamento & purificação
14.
Angew Chem Int Ed Engl ; 57(40): 13145-13149, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30110128

RESUMO

The one-step removal of multi-component gases based on a single material will significantly improve the efficiency of separation processes but it is challenging, owing to the difficulty to precisely fabricate porous materials with multiple binding sites tailored for different guest molecules. Now a niobium oxide-fluoride anion-pillared interpenetrated material ZU-62 (NbOFFIVE-2-Cu-i, NbOFFIVE=NbOF52- ) is presented. It features asymmetric O/F node coordination for the simultaneous removal of trace propyne and propadiene from propylene. The narrow distribution nanospace (aperture of Site I 6.75 Å, Site II 6.94 Å, Site III 7.20 Å) derived from the special coordination geometry within ZU-62 customized the corresponding energy-favorable binding sites for the propyne and propadiene that enable propadiene uptake (1.74 mmol g-1 ) as well as excellent propyne uptake (1.87 mmol g-1 ) under ultra-low pressure (5000 ppm). The multisite capture mechanism was revealed by modeling studies.

15.
ACS Appl Mater Interfaces ; 10(19): 16628-16635, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29671578

RESUMO

The separation of carbon dioxide (CO2) from hydrocarbons is a critical process for the production of clean energy and high-purity chemicals. Adsorption based on molecular sieving is an energy-saving separation process; however, most of molecular sieves with narrow and straight pore channels exhibit low CO2 uptake capacity. Here, we report that a twofold interpenetrated copper coordination network with a consecutive pocket-like pore structure, namely, SIFSIX-14-Cu-i (SIFSIX = hexafluorosilicate, 14 = 4,4'-azopyridine, i = interpenetrated) is a remarkable CO2/CH4 molecular sieving adsorbent which completely blocks the larger CH4 molecule with unprecedented selectivity, whereas it has excellent CO2 uptake (172.7 cm3/cm3) under the ambient condition. The exceptional separation performance of SIFSIX-14-Cu-i is attributed to its unique pore shape and functional pore surface, which combine a contracted pore window (3.4 Å) and a relatively large pore cavity decorated with high density of inorganic anions. Dispersion-corrected density functional theory calculation and neutron powder diffraction were performed to understand the CO2 binding sites. The practical feasibility of SIFSIX-14-Cu-i for CO2/CH4 mixtures separation was validated by experimental breakthrough tests. This study not only demonstrates the great potential of SIFSIX-14-Cu-i for CO2 separation but also provides important clues for other gas separations.

16.
J Am Chem Soc ; 140(13): 4596-4603, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29540058

RESUMO

Research on hydrogen-bonded organic frameworks (HOFs) has been developed for quite a long time; however, those with both established permanent porosities and functional properties are extremely rare due to weak hydrogen-bonding interactions among molecular organic linkers, which are much more fragile and difficult to stabilize. Herein, through judiciously combining the superiority of both the moderately stable coordination bonds in metal-organic frameworks and hydrogen bonds, we have realized a microporous hydrogen-bonded metal-complex or metallotecton framework HOF-21, which not only shows permanent porosity, but also exhibits highly selective separation performance of C2H2/C2H4 at room temperature. The outstanding separation performance can be ascribed to sieving effect confined by the fine-tuning pores and the superimposed hydrogen-bonding interaction between C2H2 and SiF62- on both ends as validated by both modeling and neutron powder diffraction experiments. More importantly, the collapsed HOF-21 can be restored by simply immersing it into water or salt solution. To the best of our knowledge, such extraordinary water stability and restorability of HOF-21 were observed for the first time in HOFs, underlying the bright perspective of such new HOF materials for their industrial usage.

17.
Adv Mater ; 30(10)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29345384

RESUMO

Propyne/propylene (C3 H4 /C3 H6 ) separation is a critical process for the production of polymer-grade C3 H6 . However, optimization of the structure of porous materials for the highly efficient removal of C3 H4 from C3 H6 remains challenging due to their similar structures and ultralow C3 H4 concentration. Here, it is first reported that hybrid ultramicroporous materials with pillared inorganic anions (SiF62- = SIFSIX, NbOF52- = NbOFFIVE) can serve as highly selective C3 H4 traps for the removal of trace C3 H4 from C3 H6 . Especially, it is revealed that the pyrazine-based ultramicroporous material with square grid structure for which the pore shape and functional site disposition can be varied in 0.1-0.5 Å scale to match both the shape and interacting sites of guest molecule is an interesting single-molecule trap for C3 H4 molecule. The pyrazine-based single-molecule trap enables extremely high C3 H4 uptake under ultralow concentration (2.65 mmol g-1 at 3000 ppm, one C3 H4 per unit cell) and record selectivity over C3 H6 at 298 K (>250). The single-molecule binding mode for C3 H4 within ultramicroporous material is validated by X-ray diffraction experiments and modeling studies. The breakthrough experiments confirm that anion-pillared ultramicroporous materials set new benchmarks for the removal of ultralow concentration C3 H4 (1000 ppm on SIFSIX-3-Ni, and 10 000 ppm on SIFSIX-2-Cu-i) from C3 H6 .

18.
Angew Chem Int Ed Engl ; 56(51): 16282-16287, 2017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-28980379

RESUMO

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 Šscale 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 (C4 H6 ) or 1-butene (n-C4 H8 ). Combining the molecular recognition and size-sieving effect, these materials unexpectedly realized the sieving of C4 H6 /n-C4 H8 , C4 H6 /iso-C4 H8 , and n-C4 H8 /iso-C4 H8 with high capacity.

19.
Chem Commun (Camb) ; 53(81): 11150-11153, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28871296

RESUMO

Two solvent-induced porous hydrogen-bonded organic frameworks have been obtained, and their synthesis, crystal structures, gas sorption behaviours and fluorescence sensing applications have been systematically investigated to elucidate the solvent effects on the structures and functionalities of HOFs.

20.
ChemSusChem ; 10(17): 3368-3377, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28703458

RESUMO

Serious environmental concerns have led to a great demand for efficient uptake of NH3 by solvents. However, traditional aqueous absorbents have many shortcomings and efforts to use ionic liquids have met with limited success. A hybrid deep eutectic solvents (DESs) designed with a flexible hydrogen-bonded supramolecular network exhibits both exceptional NH3 uptake capacity and superior desorption-regeneration performance, along with superb NH3 /CO2 selectivity and environmental merit. Elucidated by molecular dynamic simulations and spectroscopic analysis, the abundant hydrogen-bonding sites in the hybrid DESs bind every atom of the NH3 molecule and enable strong physical reversible solvation, whereas the multiple interactions among the hybrid components create a flexible hydrogen-bonded supramolecular network and allow for solvent-unbreaking absorption to ensure the full participation of the solvent and process stability. A mass solubility of NH3 up to 0.13 g g-1 was achieved at 313 K and 101 kPa by the hybrid DES choline chloride/resorcinol/glycerol (1:3:5), which is higher than all reported ionic liquids and ordinary DESs. Moreover, the performance remained the same after ten absorption-desorption cycles and the DESs could be easily regenerated.


Assuntos
Amônia/química , Hidrogênio/química , Solventes/química , Absorção Fisico-Química , Dióxido de Carbono/química , Ligação de Hidrogênio , Conformação Molecular , Simulação de Dinâmica Molecular
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