Hauser B.G.,Northwestern University |
Farha O.K.,Northwestern University |
Exley J.,Micromeritics Instrument Co. |
Hupp J.T.,Northwestern University
Chemistry of Materials
Thermal treatment of highly stable porous organic polymers based upon the Yamamoto polymerization of 2,2′,7,7′-tetrabromo-9,9′- spirobifluorene was done. The polymers are shown to be thermally and chemically stable. Upon thermal treatment the polymers are shown to have BET surface areas of ca. 2,000 m2/g and 2,500 m2/g respectively. © 2012 American Chemical Society. Source
Wang H.,Rutgers University |
Yao K.,King Abdullah University of Science and Technology |
Zhang Z.,Jinan University |
Jagiello J.,Micromeritics Instrument Co. |
And 3 more authors.
In industry, cryogenic rectification for separating xenon from other noble gases such as krypton and argon is an energy and capital intensive process. Here we show that a microporous metal-organic framework, namely Co 3(HCOO)6 is capable of effective capture and separation of xenon from other noble gases. Henry's constant, isosteric heat of adsorption (Qst), and IAST selectivity are calculated based on single component sorption isotherms. Having the highest Qst reported to date, Co 3(HCOO)6 demonstrates high adsorption capacity for xenon and its IAST selectivity for Xe-Kr is the largest among all MOFs investigated to date. To mimic real world conditions, breakthrough experiments are conducted on Xe-Kr binary mixtures at room temperature and 1 atmosphere. The results are consistent with the calculated data. These findings show that Co 3(HCOO)6 is a promising candidate for xenon capture and purification. Our gas adsorption measurements and molecular simulation study also reveal that the adsorption of xenon represents the first example of commensurate adsorption of atomic gases near ambient conditions. © 2014 The Royal Society of Chemistry. Source
Seredych M.,City College of New York |
Jagiello J.,Micromeritics Instrument Co. |
Bandosz T.J.,City College of New York
Nanoporous S-doped carbon and its composites with graphite oxide were tested as adsorbents of CO2 (1 MPa at 0°C) after degassing either at 120 °C or 350 °C. The adsorption capacities were over 4 mmol/g at ambient pressure and 8 mmol/g at 0.9 MPa in spite of a low volume of micropores. The nitrogen adsorption experiments showed an increase in porosity upon an increase in the degassing temperature. The extent of this effect depends on the stability of surface groups. Interestingly, the CO2 adsorption, especially at low pressure, was not affected. The good performance is due to the presence of ultramicropores similar in sizes to CO2 molecule and to sulfur in various functionalities. Sulfur incorporated to aromatic rings enhances CO2 adsorption via acid-base interactions in micropores. Moreover, sulfonic acids, sulfoxides and sulfones attract CO2 via polar interactions. Hydrogen bonding of CO2 with acidic groups on the surface can also play an important role in the CO2 retention. These carbons have high potential for application as CO2 removal media owing to their high degree of pore space utilization. The results obtained also show that high degassing temperatures might result in the decomposition of surface groups and thus in changes in surface interactions. © 2014 Elsevier Ltd. All rights reserved. Source
Xu R.,Micromeritics Instrument Co.
This review covers the progress of light scattering applications in the field of particle characterization in the past decade. The review addresses static light scattering (the measurement of scattering intensities due to light-particle interaction at various spatial locations), dynamic light scattering (the measurement of scattering due to light-particle interaction as a function of time), and scattering tracking analysis (the tracking of particle movement through scattering measurement). © 2014 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved. Source
Balzer C.,Bavarian Center for Applied Energy Research |
Wildhage T.,Bavarian Center for Applied Energy Research |
Braxmeier S.,Bavarian Center for Applied Energy Research |
Reichenauer G.,Bavarian Center for Applied Energy Research |
Olivier J.P.,Micromeritics Instrument Co.
N2 and CO2 sorption measurements with in situ dilatometry implemented in a commercial volumetric sorption instrument were performed at 77 and 273 K, respectively. The resolution of the linear deformation was about ±0.2 μm. To separate effects due to microporosity, external surface area and mesopores synthetic porous carbons (xerogels) with different external surface areas and microporosities were applied as a model system. The experimental data show that the relative length change of the monolithic carbon xerogels investigated passes different stages during ad- and desorption, which are connected to micropore-, multilayer- and mesopore-sorption. The length change observed in the range of micropore and surface adsorption was found to be nonmonotonic and to take negative as well as positive values, with the maximum swelling observed being on the order of 4°. With respect to the length change, the micropore structure seems to have the most significant impact on the overall length change, while the external surface is only of minor importance. Quantiative analysis of the deformation according to the models of Bangham and Scherer for the length change in the range of multilayer- and mesopore-adsorption allows extracting the macrosopic as well as the skeletal Young's modulus. © 2011 American Chemical Society. Source