Abstract
The density of He adsorbed in the cylindrical micropores of zeolites NaY and KL has been determined by He adsorption at 4.2K. He adsorption isotherms were then compared with N2 adsorption isotherms at 77K. Crystallographic considerations of the micropore volumes gave the density of the He adsorbed layer, which is necessary for assessment of ultramicroporosity of less-crystalline microporous solids, such as activated carbons. The determined density of He adsorbed in the cylindrical micropores of the zeolite was in the range 0.22 to 0.26 gml−1, greater than that of He adsorbed on a flat surface (0.202 gml−1). A value for the density of He between 0.20 to 0.22 gml−1 is recommended for evaluation of ultramicroporosity of a slit-shaped microporous system such as activated carbon.
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References
Antoniou, A.A., Adsorption of4He on Spheron and Grafoil between 2 and 30 K,J. Chem. Soc., Faraday Trans. 1,82, 483(1986).
Breck, D.W., Crystalline Molecular Sieves,J. Chem. Ed.,48, 678(1964).
Breck, D.W. and R.W. Grose, Correlation of the Calculated Intracrystalline Void Volumes and Limiting Adsorption Volumes in Zeolites,Advan. Chem. Ser.,121, 319(1973).
Carrot, P.J.M., R.M. Roberts, and K.S.W. Sing, “Adsorption of Nitrogen by porous and Non-Porous Carbons,”Carbon,25, 59 (1987).
Dubinin, M.M., The Potential Theory of Adsorption of Gases and Vapors for Adsorbents with Energetically Nonuniform Surfaces,Chem. Rev.,60, 235(1960).
Dubinin, M.M., “Porous Structures and Adsorption Properties of Active Carbons,”Chemistry and Physics of Carbon,2, 51 (1966).
Everett, D.H. and J.C. Powl, Adsorption in Slit-like and Cylindrical Micropores in the Henry's Law Region,J. Chem. Soc.,72, 619(1976).
Fukasawa, J., C.D. Poon and E.T. Samulski, Deuterium NMR Investigation of Benzene Adsorbed on Boehmite Glasses,Langmuir,7, 1727(1991).
Grillet, Y., F. Rouquerol and J. Rouquerol, Two-Dimensional Freezing of Nitrogen or Argon on Differently Graphitized Carbons,J. Colloid Interface Sci.,70, 239(1979).
Gregg, S.J. and K.S.W. Sing,Adsorption, Surface Area and Porosity, Chap. 4, Academic Press, London, 1982.
IUPAC, “Physisorption Data for Gas/Solid Systems with Special Reference to the Determination of Surface Area and Porosity,”Pure & Appl. Chem.,57, 603 (1985).
Jaroniec, M., R.K. Gilpin, K. Kaneko, and J. Choma, “Evaluation of Energetic Heterogeneity and Microporosity of Activated Carbon Fibers on the Basis of Gas Adsorption Isotherms,”Langmuir,7, 2719 (1991).
Kaneko, K., C. Ishii, M. Ruike, and H. Kuwabara, “Origin of Superhigh Surface Area and Microcrystalline Graphitic Structures of Activated Carbons,”Carbon,30, 1075 (1992).
Kaneko, K., N. Setoyama, T. Suzuki and H. Kuwabara, Ultramicroporosimetry of Porous Solids by He Adsorption,Fundam, of Adsorption 2, M. Suzuki(Eds.), pp. 315, Kodansya, Tokyo, 1993.
Kato, H., K. Ishioh, N. Wada, T. Ito and T. Watanabe, Motional States of3He and4He in the One-Dimensional Channels of K-L Zeolite,J. Low Temp. Phys.,68, 321(1987).
Kuwabara, H., T. Suzuki and K. Kaneko, Microporous Carbon Fibers evidenced by Helium Adsorption at 4.2 K.,J. Chem. Soc.,87, 1915(1991).
Rodriguez-Reinoso, F. et. al, “The Combined Use of Different Approaches in the Characterization of Microporous Carbons,”Carbon,27, 23 (1989).
Rouquerol, J,et. al, “A Critical Assessment of Quasi-Equilibrium Gas Adsorption Techniques in Volumetry, Gravimetry or Calorimetry”,Characterization of Porous Solids, K.K. Ungeret. al., (Eds.) pp. 67, Elsevier, Amsterdam, 1988.
Setoyama, N., M. Ruike, T. Kasu, T. Suzuki and K. Kaneko, Surface Characterization of Microporous Solids with He adsorption and Small Angle X-ray Scattering,Langmuir,9, 2612(1993).
Steele, W.A., Concerning a Theory of Multilayer Adsorption with particular Reference to Adsorbed Helium,J. Chem. Phys.,25, 819 (1956).
Steele, W.A., Thermodynamic Properties of Adsorbed Helium,J. Low Temp. Phys.,3, 257(1970).
Walker, Jr., P.L., L.G. Austin and S.P. Nandi, Activated Diffusion of Gases in Molecular-Sieve Materials,Chemistry and Physics of Carbon,2, 257 (1966).
Wang, Z.M. and K. Kaneko, “Oriented Molecular States of SO2 Confined in a Slit-shaped Graphitic Subnanospace from Calorimetry,”J. Phys. Chem., in press.
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Setoyama, N., Kaneko, K. Density of He adsorbed in micropores at 4.2K. Adsorption 1, 165–173 (1995). https://doi.org/10.1007/BF00705003
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DOI: https://doi.org/10.1007/BF00705003