Jump to ContentJump to Main Navigation
Show Summary Details
More options …

American Mineralogist

Journal of Earth and Planetary Materials

Ed. by Baker, Don / Xu, Hongwu / Swainson, Ian

IMPACT FACTOR 2018: 2.631

CiteScore 2018: 2.55

SCImago Journal Rank (SJR) 2018: 1.355
Source Normalized Impact per Paper (SNIP) 2018: 1.103

See all formats and pricing
More options …
Volume 102, Issue 7


Dehydration studies of natrolites: Role of monovalent extra-framework cations and degree of hydration

Yongmoon Lee / Docheon Ahn / Thomas Vogt
  • Department of Chemistry and Biochemistry & NanoCenter, University of South Carolina, Columbia, South Carolina 29208, U.S.A.
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Yongjae Lee
  • Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China
  • Department of Earth System Sciences, Yonsei University, Seoul 03722, South Korea
  • Email
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
Published Online: 2017-07-17 | DOI: https://doi.org/10.2138/am-2017-5902


Rietveld refinements of natrolite analogs [M16Al16Si24O80·nH2O, M-NAT, M = Li, Na, Ag, K, NH4, Rb, and Cs, 14.0(1) < n <17.6(9)] at temperatures between 75 and 675 K using synchrotron X-ray powder diffraction reveal the impact H2O content and monovalent extra-framework cations (EFC) contained in the channels have on dehydration and thermal expansion. Dehydration temperatures are found to be inverse proportional to the size of the EFC. Isostructural K-, Rb-, and Cs-NAT with disordered EFC-H2O distribution exhibit negative thermal expansions before dehydration. The thermal expansion coefficients increase linearly from K-, Rb-, to Cs-NAT, the latter exhibits has the smallest thermal expansion coefficient of all NAT analogs [3.0(1) × 10−6 K−1]. After dehydration, the EFC distribution of K-, Rb-, and Cs-NAT becomes ordered and their thermal expansion coefficients become positive. In the isostructural Li-, Na-, and Ag-NAT with ordered EFC-H2O distribution, the thermal expansion coefficients are positive for the Li- and Ag-NAT and negative for Na-NAT. After dehydration, this behavior is reversed, and Li- and Ag-NAT show negative thermal expansion coefficients, whereas Na-NAT exhibits a positive thermal expansion. Upon dehydration, the channels in Li- and Ag-NAT reorient: the rotation angles of the fibrous chain units, ψ, change from 26.4(2)° to –29.6(2)° in Li-NAT and from 22.3(2)° to –23.4(2)° in Ag-NAT. The structure models of the dehydrated Li- and Ag-NAT reveal that the change in the channel orientation is due to the migration of the Li+ and Ag+ cations from the middle of the channel to the walls where they are then coordinated by four framework oxygen atoms. Further heating of these dehydrated phases results in structural collapse and amorphization. X-ray O1s K-edge absorption spectroscopy reveals that the binding energy between the EFC and the oxygen of the framework (Of) is larger in Li- and Ag-NAT than in Cs-NAT due to an increase of the basicity of the framework oxygen. The interaction between the H2O molecules and EFCs allow a clear separation in structures with disordered H2O molecules in the center of the channels (K-, NH4-, Rb-, and Cs-NAT) and those in close proximity to the aluminosilicate framework (Li-, Na-, and Ag-NAT), which leads to systematic dehydration and thermal expansion behaviors. Our structure work indicates that the effects of EFCs are more important to stabilize the NAT structure than the degree of hydration.

Keywords: Thermal expansion; natrolite; dehydration; rietveld refinement; oxygen K-edge X-ray absorption spectroscopy

References cited

  • Baur, W.H., and Joswig, W. (1996) The phases of natrolite occuring during dehydration and rehydration studied by single-crystal X-ray diffraction methods between room temperature and 923K. Neues Jahrbuch für Mineralogie, 171–187.Google Scholar

  • Dollase, W.A. (1986) Correction of intensities for preferred orientation in powder diffractometry: Application of the March Model. Journal of Applied Crystallography, 19, 267–272.Google Scholar

  • Fang, J.H. (1963) Cell dimensions of dehydrated natrolite. American Mineralogist, 48, 414–417.Google Scholar

  • Hwang, G.C., Shin, T.J., Blom, D.A., Vogt, T., and Lee, Y. (2015) Pressure-induced amorphization of small pore zeolites—the role of cation-H2O topology and anti-glass formation. Scientific Reports, 5, 15056.Google Scholar

  • Klaproth, M.H. (1803) Gesellschaft Naturforschende Freunde zu Berlin, Neue Schriften, 4, 243–248.Google Scholar

  • Kremleva, A., Vogt, T., and Rösch, N. (2013) Monovalent cation-exchanged natrolites and their behavior under pressure. A computational study. Journal of Physical Chemistry C,117, 19,020–19,030.Google Scholar

  • Larson, A., and von Dreele, R.B. (1986) General Structure Analysis System (GSAS). Los Alamos National Laboratory, New Mexico, Report LAUR, 86-748.Google Scholar

  • Lee, Y., Lee, Y., and Seoung, D. (2010) Natrolite may not be a “soda-stone” anymore: Structural study of fully K-, Rb-, and Cs-exchanged natrolite. American Mineralogist, 95, 1636–1641.Google Scholar

  • Lee, Y., Seoung, D., Jang, Y.N., Bai, J., and Lee, Y. (2011a) Structural studies of NH4-exchanged natrolites at ambient conditions and high temperature. American Mineralogist, 96, 1308–1315.Google Scholar

  • Lee, Y., Seoung, D., and Lee, Y. (2011b) Natrolite is not a “soda-stone” anymore: Structural study of alkali (Li+), alkaline-earth (Ca2+, Sr2+, Ba2+) and heavy metal (Cd2+, Pb2+, Ag+) cation-exchanged natrolites. American Mineralogist, 96, 1718–1724.Google Scholar

  • Lee, Y., Seoung, D., Liu, D., Park, M.B., Hong, S.B., Chen, H., Bai, J., Kao, C.-C., Vogt, T., and Lee, Y. (2011c) In-situ dehydration studies of fully K-, Rb-, and Cs-exchanged natrolites. American Mineralogist, 96, 393–401.Google Scholar

  • Lee, Y., Lee, J.-S., Kao, C.-C., Yoon, J.-H., Vogt, T., and Lee, Y. (2013) Role of cation–water disorder during cation exchange in small-pore zeolite sodium natrolite. The Journal of Physical Chemistry C,117, 16119–16126.Google Scholar

  • Pauling, L. (1930) The structure of some sodium and calcium aluminosilicates. Proceedings of the National Academy of Sciences,16, 453–459.Google Scholar

  • Reeuwijk, V. (1972) High-temperature phases of zeolites of the natrolite group. American Mineralogist, 57, 499–510.Google Scholar

  • Rietveld, H.M. (1969) A profile refinement method for nuclear and magnetic structures. Journal of Applied Crystallography, 2, 65–71.Google Scholar

  • Rinne, F. (1890) Über die umänderungen welche die zeolithe durch erwärmen bei und nach dem trübwerden erfahren. Sitzungsberichte der Preussischen Akademie der Wissenschaften, Physikalisch-Mathematische Klasse, 46, 1163–1207.Google Scholar

  • Seoung, D., Lee, Y., Kao, C.C., Vogt, T., and Lee, Y. (2013) Super-hydrated zeolites: Pressure-induced hydration in natrolites. Chemistry—A European Journal, 19, 10,876–10,883.Google Scholar

  • Seoung, D., Lee, Y., Kao, C.C., Vogt, T., and Lee, Y. (2015) Two-step pressure-induced superhydration in small pore natrolite with divalent extra-framework cations. Chemistry of Materials, 27, 3874–3880.Google Scholar

  • Stahl,K., and Hanson, J. (1994) Real-time X-ray synchrotron powder diffraction studies of the dehydration processes in scolecite and mesolite. Journal of Applied Crystallography, 27, 543–550.Google Scholar

  • Thompson, P., Cox, D.E., and Hastings, J.B. (1987) Rietveld refinement of Debye-Scherrer synchrotron X-ray data from Al2O3. Journal of Applied Crystallography, 20, 79–83.Google Scholar

  • Toby, B.H. (2001) EXPGUI, a graphical user interface for GSAS. Journal of Applied Crystallography, 34, 210–213.Google Scholar

  • Vayssilov, G.N., and Rösch, N. (1999) Density functional studies of alkali-exchanged zeolites: Basicity and core-level shifts of framework oxygen atoms. Journal of Catalysis, 186, 423–432.Google Scholar

  • Wang, H.-W., and Bish, D.L. (2008) A PH2O-dependent structural phase transition in the zeolite natrolite. American Mineralogist, 93, 1191–1194.Google Scholar

  • Wernet, P., Nordlund, D., Bergmann, U., Cavalleri, M., Odelius, N., Ogasawara, H., Näslund, L.Å., Hirsch, T.K., Ojamäe, L., Glatzel, P., Pettersson, L.G.M., and Nilsson, A. (2004) The structure of the first coordination shell in liquid water. Science, 304, 995–999.Google Scholar

  • Wu, L., Navrotsky, A., Lee, Y., and Lee, Y. (2013) Thermodynamic study of alkali and alkaline-earth cation-exchanged natrolites. Microporous and Mesoporous Materials, 167, 221–227.Google Scholar

  • Yamazaki, A., Otsuka, R., and Nishido, H. (1986) The thermal behavior of K-exchanged forms of natrolite. Thermochimica Acta, 109, 237–242.Google Scholar

About the article

Received: 2016-06-27

Accepted: 2017-02-26

Published Online: 2017-07-17

Published in Print: 2017-07-26

Citation Information: American Mineralogist, Volume 102, Issue 7, Pages 1462–1469, ISSN (Online) 1945-3027, ISSN (Print) 0003-004X, DOI: https://doi.org/10.2138/am-2017-5902.

Export Citation

© 2017 by Walter de Gruyter Berlin/Boston.

Comments (0)

Please log in or register to comment.
Log in