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https://www.readbyqxmd.com/read/28434232/modeling-bi-solute-adsorption-of-aromatic-compounds-based-on-adsorbed-solution-theories-asts
#1
Huichun Zhang, Shubo Wang
A large number of organic contaminants are commonly found in industrial and municipal wastewaters. For proper unit design to remove contaminant mixtures by adsorption, multi-component adsorption equilibrium models are necessary. The present work examined the applicability of Ideal Adsorbed Solution Theory (IAST), a prevailing thermodynamic model, and its derivatives, i.e., Segregated IAST (SIAST) and Real Adsorbed Solution Theory (RAST), to bi-solute adsorption of organic compounds onto a hyper-crosslinked polystyrene resin, MN200...
April 24, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28374991/promoting-and-tuning-porosity-of-flexible-ether-linked-phthalazinone-based-covalent-triazine-frameworks-utilizing-substitution-effect-for-effective-co2-capture
#2
Kuanyu Yuan, Cheng Liu, Lishuai Zong, Guipeng Yu, Shengli Cheng, Jinyan Wang, Zhihuan Weng, Xigao Jian
Five porous ether-linked phthalazinone-based covalent triazine frameworks (PHCTFs) were successfully constructed via ionothermal polymerizations from flexible dicyano monomers containing asymmetric, twisted, and N-heterocyclic phthalazinone structure. All the building blocks could be easily prepared by simple and low-cost aromatic nucleophilic substitution reactions, showing the large-scale application potential of thermal stable phthalazinone structure in constructing porous materials. Generally, the flexible building blocks are avoided to prevent the networks from collapsing in constructing high surface area porous materials...
April 10, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28368569/nanoporous-boron-nitride-as-exceptionally-thermally-stable-adsorbent-role-in-efficient-separation-of-light-hydrocarbons
#3
Dipendu Saha, Gerassimos Orkoulas, Samuel Yohannan, Hoi Chun Ho, Ercan Cakmak, Jihua Chen, Soydan Ozcan
In this work, nanoporous boron nitride sample was synthesized with a Brunauer-Emmett-Teller (BET) surface area of 1360 m(2)/g and particle size 5-7 μm. The boron nitride was characterized with X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and electron microscopy (TEM and SEM). Thermogravimetric analysis (TGA) under nitrogen and air and subsequent analysis with XPS and XRD suggested that its structure is stable in air up to 800 °C and in nitrogen up to 1050 °C, which is higher than most of the common adsorbents reported so far...
April 11, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28177165/a-robust-metal-organic-framework-combining-open-metal-sites-and-polar-groups-for-methane-purification-and-co2-fluorocarbon-capture
#4
Cheng-Xia Chen, Shao-Ping Zheng, Zhang-Wen Wei, Chen-Chen Cao, Hai-Ping Wang, Dawei Wang, Ji-Jun Jiang, Dieter Fenske, Cheng-Yong Su
A 3D porous perchlorinated metal-organic framework (MOF), LIFM-26, featuring dual functionality, that is, functional polar groups and open metal sites, has been synthesized using perchlorinated linear dicarboxylate to link trigonal prismatic Fe3 (μ3 -O) units. LIFM-26 exhibits good thermal and chemical stability, and possesses high porosity with a BET surface area of 1513 m(2)  g(-1) , compared with isoreticular MOF-235 and Fe3 O(F4 BDC)3 (H2 O)3 (F4 BDC=2,3,5,6-tetrafluorobenzene-1,4-dicarboxylate). Most strikingly, LIFM-26 features good gas sorption/separation performance at 298 K and 1 atm with IAST selectivity values reaching up to 36, 93, 23, 11, 46, and 202 for CO2 /CH4 , CO2 /N2 , C2 H4 /CH4 , C2 H6 /CH4 , C3 H8 /CH4 , and R22/N2 (R22=CHClF2 ), respectively, showing potential for use in biogas/natural gas purification and CO2 /R22 capture...
February 8, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28157282/chalcogenide-aerogels-as-sorbents-for-noble-gases-xe-kr
#5
Kota S Subrahmanyam, Ioannis Spanopoulos, Jaehun Chun, Brian J Riley, Praveen K Thallapally, Pantelis N Trikalitis, Mercouri G Kanatzidis
High-surface-area molybdenum sulfide (MoSx) and antimony sulfide (SbSx) chalcogels were studied for Xe/Kr gas separation. The intrinsic soft Lewis basic character of the chalcogel framework is a unique property among the large family of porous materials and lends itself to a potential new approach toward the selective separation of Xe over Kr. Among these chalcogels, MoSx shows the highest Xe and Kr uptake, reaching 0.69 mmol g(-1) (1.05 mmol cm(-3)) and 0.28 mmol g(-1) (0.42 mmol cm(-3)) respectively, at 273 K and 1 bar...
February 3, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28040539/prediction-of-the-adsorption-capacities-for-four-typical-organic-pollutants-on-activated-carbons-in-natural-waters
#6
Warisa Bunmahotama, Wei-Nung Hung, Tsair-Fuh Lin
A new model is developed to predict the competitive adsorption isotherms of atrazine, methyl tertiary butyl ether (MTBE), 2-methylisoborneol (2-MIB) and 2,4,6-trichlorophenol onto activated carbons (ACs) in natural water. Based on the Polanyi-Dubinin (PD) equation, with the limiting pore volume of adsorbent estimated from the pore size distribution data, and the Ideal adsorbed solution theory - equivalent background compound (IAST-EBC) model approximation, the model takes into account both the properties of ACs and the impact of natural organic matters in water...
December 21, 2016: Water Research
https://www.readbyqxmd.com/read/27805761/predicting-multicomponent-adsorption-isotherms-in-open-metal-site-materials-using-force-field-calculations-based-on-energy-decomposed-density-functional-theory
#7
Jurn Heinen, Nicholas C Burtch, Krista S Walton, Célia Fonseca Guerra, David Dubbeldam
For the design of adsorptive-separation units, knowledge is required of the multicomponent adsorption behavior. Ideal adsorbed solution theory (IAST) breaks down for olefin adsorption in open-metal site (OMS) materials due to non-ideal donor-acceptor interactions. Using a density-function-theory-based energy decomposition scheme, we develop a physically justifiable classical force field that incorporates the missing orbital interactions using an appropriate functional form. Our first-principles derived force field shows greatly improved quantitative agreement with the inflection points, initial uptake, saturation capacity, and enthalpies of adsorption obtained from our in-house adsorption experiments...
December 12, 2016: Chemistry: a European Journal
https://www.readbyqxmd.com/read/27788360/synthesis-and-application-of-a-new-carboxylated-cellulose-derivative-part-ii-removal-of-co-2-cu-2-and-ni-2-from-bicomponent-spiked-aqueous-solution
#8
Filipe Simões Teodoro, Oscar Fernando Herrera Adarme, Laurent Frédéric Gil, Leandro Vinícius Alves Gurgel
In the second part of this series of studies, the competitive adsorption of three binary systems Cu(2+)-Co(2+), Cu(2+)-Ni(2+) and Co(2+)-Ni(2+) on a carboxylated cellulose derivative (CTA) was evaluated in binary equimolar (1:1) metal-ion aqueous solutions. Bicomponent adsorption studies were developed as a function of contact time and initial metal ion concentration. Bicomponent adsorption kinetic data was modeled by monocomponent kinetic models of pseudo-first- (PFO) and pseudo-second-order (PSO) and a competitive kinetic model of Corsel...
February 1, 2017: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/27597151/adsorptive-separation-of-xenon-krypton-mixtures-using-a-zirconium-based-metal-organic-framework-with-high-hydrothermal-and-radioactive-stabilities
#9
Seung-Joon Lee, Tae-Ung Yoon, Ah-Reum Kim, Seo-Yul Kim, Kyung-Ho Cho, Young Kyu Hwang, Jei-Won Yeon, Youn-Sang Bae
The separation of xenon/krypton mixtures is important for both environmental and industrial purposes. The potential of three hydrothermally stable MOFs (MIL-100(Fe), MIL-101(Cr), and UiO-66(Zr)) for use in Xe/Kr separation has been experimentally investigated. From the observed single-component Xe and Kr isotherms, isosteric heat of adsorption (Qst(o)), and IAST-predicted Xe/Kr selectivities, we observed that UiO-66(Zr) has the most potential as an adsorbent among the three candidate MOFs. We performed dynamic breakthrough experiments with an adsorption bed filled with UiO-66(Zr) to evaluate further the potential of UiO-66(Zr) for Xe/Kr separation under mixture flow conditions...
December 15, 2016: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/27332669/metal-organic-gel-material-based-on-uio-66-nh2-nanoparticles-for-improved-adsorption-and-conversion-of-carbon-dioxide
#10
Liping Liu, Jianyong Zhang, Haobin Fang, Liuping Chen, Cheng-Yong Su
Metal-organic frameworks (MOFs) including the UiO-66 series show potential application in the adsorption and conversion of CO2 . Herein, we report the first tetravalent metal-based metal-organic gels constructed from Zr(IV) and 2-aminoterephthalic acid (H2 BDC-NH2 ). The ZrBDC-NH2 gel materials are based on UiO-66-NH2 nanoparticles and were easily prepared under mild conditions (80 °C for 4.5 h). The ZrBDC-NH2 -1:1-0.2 gel material has a high surface area (up to 1040 m(2)  g(-1) ) and showed outstanding performance in CO2 adsorption (by using the dried material) and conversion (by using the wet gel) arising from the combined advantages of the gel and the UiO-66-NH2 MOF...
August 19, 2016: Chemistry, An Asian Journal
https://www.readbyqxmd.com/read/27163056/extraction-of-lanthanide-and-actinide-ions-from-aqueous-mixtures-using-a-carboxylic-acid-functionalized-porous-aromatic-framework
#11
Selvan Demir, Nicholas K Brune, Jeffrey F Van Humbeck, Jarad A Mason, Tatiana V Plakhova, Shuao Wang, Guoxin Tian, Stefan G Minasian, Tolek Tyliszczak, Tsuyoshi Yaita, Tohru Kobayashi, Stepan N Kalmykov, Hideaki Shiwaku, David K Shuh, Jeffrey R Long
Porous aromatic frameworks (PAFs) incorporating a high concentration of acid functional groups possess characteristics that are promising for use in separating lanthanide and actinide metal ions, as required in the treatment of radioactive waste. These materials have been shown to be indefinitely stable to concentrated acids and bases, potentially allowing for multiple adsorption/stripping cycles. Additionally, the PAFs combine exceptional features from MOFs and inorganic/activated carbons giving rise to tunable pore surfaces and maximum chemical stability...
April 27, 2016: ACS Central Science
https://www.readbyqxmd.com/read/27126718/nanoporous-chalcogenides-for-adsorption-and-gas-separation
#12
Guido Ori, Carlo Massobrio, Annie Pradel, Michel Ribes, Benoit Coasne
The adsorption and gas separation properties of amorphous porous chalcogenides such as GeS2 are investigated using statistical mechanics molecular simulation. Using a realistic molecular model of such amorphous adsorbents, we show that they can be used efficiently to separate different gases relevant to environmental and energy applications (H2, CO2, CH4, N2). In addition to shedding light on the microscopic adsorption mechanisms, we show that coadsorption in this novel class of porous materials can be described using the ideal adsorbed solution theory (IAST)...
May 21, 2016: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/27054609/the-role-of-the-internal-molecular-free-volume-in-defining-organic-porous-copolymer-properties-tunable-porosity-and-highly-selective-co%C3%A2-adsorption
#13
Yindong Zhang, Yunlong Zhu, Jun Guo, Shuai Gu, Yuanyuan Wang, Yu Fu, Dongyang Chen, Yijun Lin, Guipeng Yu, Chunyue Pan
A series of novel azo-functionalized copolymerized networks (simply known as NOP-34 series) with tunable permanent microporosity and highly selective carbon dioxide capture are disclosed. The synthesis was accomplished by Zn-induced reductive cross-coupling copolymerization of two nitrobenzene-like building blocks with different 'internal molecular free volumes' (IMFVs), i.e., 2,7,14-trinitrotriptycene and 2,2',7,7'-tetranitro-9,9'-spirobifluorene, with different molar ratios. Increasing the content of spirobifluorene (SBF) segments with a smaller IMFV relative to that of triptycene leads to an unconventional rise-fall pattern in porosity...
April 28, 2016: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/26973086/dynamic-entangled-porous-framework-for-hydrocarbon-c2-c3-storage-co2-capture-and-separation
#14
Nivedita Sikdar, Satyanarayana Bonakala, Ritesh Haldar, Sundaram Balasubramanian, Tapas Kumar Maji
Storage and separation of small (C1-C3) hydrocarbons are of great significance as these are alternative energy resources and also can be used as raw materials for many industrially important materials. Selective capture of greenhouse gas, CO2 from CH4 is important to improve the quality of natural gas. Among the available porous materials, MOFs with permanent porosity are the most suitable to serve these purposes. Herein, a two-fold entangled dynamic framework {[Zn2 (bdc)2 (bpNDI)]⋅4DMF}n with pore surface carved with polar functional groups and aromatic π clouds is exploited for selective capture of CO2 , C2, and C3 hydrocarbons at ambient condition...
April 18, 2016: Chemistry: a European Journal
https://www.readbyqxmd.com/read/26581027/adsorptive-separation-of-methanol-acetone-on-isostructural-series-of-metal-organic-frameworks-m-btc-m-ti-fe-cu-co-ru-mo-a-computational-study-of-adsorption-mechanisms-and-metal-substitution-impacts
#15
Ying Wu, Huiyong Chen, Jing Xiao, Defei Liu, Zewei Liu, Yu Qian, Hongxia Xi
The adsorptive separation properties of M-BTC isostructural series (M = Ti, Fe, Cu, Co, Ru, Mo) for methanol-acetone mixtures were investigated by using various computational procedures of grand canonical Monte Carlo simulations (GCMC), density functional theory (DFT), and ideal adsorbed solution theory (IAST), following with comprehensive understanding of adsorbate-metal interactions on the adsorptive separation behaviors. The obtained results showed that the single component adsorptions were driven by adsorbate-framework interactions at low pressures and by framework structures at high pressures, among which the mass effects, electrostatics, and geometric accessibility of the metal sites also played roles...
December 9, 2015: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/26515022/adsorptive-separation-of-acetylene-from-light-hydrocarbons-by-mesoporous-iron-trimesate-mil-100-fe
#16
Ji Woong Yoon, Ji Sun Lee, Sukyung Lee, Kyoung Ho Cho, Young Kyu Hwang, Marco Daturi, Chul-Ho Jun, Rajamani Krishna, Jong-San Chang
A reducible metal-organic framework (MOF), iron(III) trimesate, denoted as MIL-100(Fe), was investigated for the separation and purification of methane/ethane/ethylene/acetylene and an acetylene/CO2 mixtures by using sorption isotherms, breakthrough experiments, ideal adsorbed solution theory (IAST) calculations, and IR spectroscopic analysis. The MIL-100(Fe) showed high adsorption selectivity not only for acetylene and ethylene over methane and ethane, but also for acetylene over CO2 . The separation and purification of acetylene over ethylene was also possible for MIL-100(Fe) activated at 423 K...
December 7, 2015: Chemistry: a European Journal
https://www.readbyqxmd.com/read/26477589/combination-of-optimization-and-metalated-ligand-exchange-an-effective-approach-to-functionalize-uio-66-zr-mofs-for-co2-separation
#17
Zhigang Hu, Samuel Faucher, Yingying Zhuo, Yao Sun, Songnan Wang, Dan Zhao
The strategy to functionalize water-stable metal-organic frameworks (MOFs) in order to improve their CO2 uptake capacities for efficient CO2 separation remains limited and challenging. We herein present an effective approach to functionalize a prominent water-stable MOF, UiO-66(Zr), by a combination of optimization and metalated-ligand exchange. In particular, by systematic optimization, we have successfully obtained UiO-66(Zr) of the highest BET surface area reported so far (1730 m(2)  g(-1) ). Moreover, it shows a hybrid Type I/IV N2 isotherm at 77 K and a mesopore size of 3...
November 23, 2015: Chemistry: a European Journal
https://www.readbyqxmd.com/read/26449991/a-versatile-al-iii-based-metal-organic-framework-with-high-physicochemical-stability
#18
Zhuo-Wei Wang, Min Chen, Chun-Sen Liu, Xi Wang, Hui Zhao, Miao Du
A unique Al(III) -based metal-organic framework (467-MOF) with two types of square channels has been designed and synthesized by using a flexible tricarboxylate ligand under solvothermal conditions. 467-MOF exhibits superior thermal and chemical stability and, moreover, shows high CO2 sorption selectivity over H2 , with a selectivity, based on the ideal adsorbed solution theory (IAST) of approximately 45 at 273 or 293 K. Furthermore, its solvent-dependent photoluminescence makes it an applicable sensor in the detection of nitrobenzene explosives through fluorescence quenching...
November 23, 2015: Chemistry: a European Journal
https://www.readbyqxmd.com/read/26165859/separation-of-benzene-from-mixtures-with-water-methanol-ethanol-and-acetone-highlighting-hydrogen-bonding-and-molecular-clustering-influences-in-cubtc
#19
Juan José Gutiérrez-Sevillano, Sofia Calero, Rajamani Krishna
Configurational-bias Monte Carlo (CBMC) simulations are used to establish the potential of CuBTC for separation of water/benzene, methanol/benzene, ethanol/benzene, and acetone/benzene mixtures. For operations under pore saturation conditions, the separations are in favor of molecules that partner benzene; this is due to molecular packing effects that disfavor benzene. CBMC simulations for adsorption of quaternary water/methanol/ethanol/benzene mixtures show that water can be selectively adsorbed at pore saturation, making CuBTC effective in drying applications...
August 21, 2015: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/26114815/hydroquinone-and-quinone-grafted-porous-carbons-for-highly-selective-co2-capture-from-flue-gases-and-natural-gas-upgrading
#20
Jun Wang, Rajamani Krishna, Jiangfeng Yang, Shuguang Deng
Hydroquinone and quinone functional groups were grafted onto a hierarchical porous carbon framework via the Friedel-Crafts reaction to develop more efficient adsorbents for the selective capture and removal of carbon dioxide from flue gases and natural gas. The oxygen-doped porous carbons were characterized with scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. CO2, CH4, and N2 adsorption isotherms were measured and correlated with the Langmuir model...
August 4, 2015: Environmental Science & Technology
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