Dehydration Characteristics of Cationic Surfactant-Modified Montmorillonite

양이온성 계면활성제로 표면개질된 몬모릴로나이트의 탈수 특성

  • Seung Yeop Lee (School of Earth Environmental Sciences, Seouul National University) ;
  • Soo Jin Kim (School of Earth Environmental Sciences, Seouul National University)
  • Published : 2002.12.01

Abstract

The dehydration of hexadecyltrimethylammonium (HDTMA)-exchanged montmorillonite has been studied using X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). The dehydration in HDTMA-montmorillonite seems to influence the swelling behavior of the organo-clay during heating. The basal d(001) spacing vs temperature curve of the HDTMA-montmorillonite has one broad swelling edge with a shoulder on the low-temperature side. We believe that the shoulder at $100^{\circ}C$ for the HDTMA-montmorillonite is due to interlayer swelling induced by the initial rearrangement of surfactants, and the second edge at $200^{\circ}C$ is caused by interlayer swelling resulting from the secondary vertical reorientation of alkyl chains. It seems that the dehydration of organo-clay induces a reorientation of the alkyl chains by transition to more vertical position relative to the silicate sheets, allowing instantly greater d-spacing.

HDTMA로 표면개질된 몬모릴로나이트의 탈수현상을 X-선 회절분석기와 시차주사열량측정 기(DSC)로 조사하였다 열에 의한 HDTMA-몬모릴로나이트의 탈수작용은 유기점토의 팽창거동에 영향을 주었다. HDTHA-몬모릴로나이트의 기저d(001)두께/온도변화 곡선은 크기가 다른 2개의 팽창피크를 보여주었다. 이것은 일차적으로 계면활성제의 정렬에 의한 점토광물의 층간팽창이 10$0^{\circ}C$ 부근에서 발생하고 알킬고리의 이차적인 수직배열에 의한 층간팽창이 20$0^{\circ}C$ 부근에서 일어났음을 가리킨다. 따라서, 이러한 결과는 유기점토의 탈수작용에 의해 점토 규산염층에 상대적으로 수직적인 알킬고리의 배열이 활성화되며, 소규모의 층간팽창을 야기한다는 것을 지시한다.

Keywords

References

  1. Anderson , M.A., Trouw, F.R., and Tam, C.N. (1999) Properties of water in calcium and hexadecy Itri methy Iammoniurn -exchanged bentonite. Clays Clay Miner., 47, 28-35.
  2. Carter , D.L., Mortland , M.M., and Kemper, W.D.(1986) Specific surface . In: Klute, A. (ed.),Methods of Soil Analysis . SSSA Book Series 5,Am. Soc. Agron . and Soil Sci. Am, 413-423.
  3. De, D.K., Das Kanungo, J.L., and Chakravarti,S.K. (1974) Interaction of crystal violet and malachite green with bentonite and their desorption by inorganic and surface active quaternary ammonium ions. Indian J. Chem., 12,165-166.
  4. Hendershot, W.H. and Duquette , M. (1986) A simple barium chloride method for determining cation exchange capacity and exchangeable cations. Soil Sci. Soc. Am. J., 50, 605-608.
  5. Jaynes, W.F. and Boyd, S.A. (1991) Clay mineral type and organic compound sorption by hexadecyltrimethylammonium-exchanged clays. Soil Sci. Soc. Am. J., 55, 43-48.
  6. Kibbey, T.C.G. and Hayes, K.F. (1993) Partitioning and UV absorption studies of phenanthrene on cationic surfactant-coated silica . Environ. Sci. Technol., 27, 2168-2173.
  7. Kung, K.S. and Hayes, K.F. (1993) Fourier transform infrared spectroscopic study of the adsorption of cetyltrimethylammonium bromide and cetylpyridinium chloride on silica. Langmuir, 9, 263-267.
  8. Lagaly, G. (1994) Layer charge determination by alkylammonium ions. In: Mermut, A.R. (ed.),Layer Charge Characteristics of 2: I Silicate Clay Minerals, CMS Workshop Lectures, Vol.6, The Clay Minerals Society, 2-46.
  9. Lee, S.Y. and Kim, SJ. (2002) Expansion of smectite by hexadecyltrimethylammonium. Clays Clay Miner., 50, 435-445.
  10. Mortland, M.M. (1970) Clay-organic complexes and interactions. Adv. Agron., 22, 75-117.
  11. Narine, D.R. and Guy, RD. (1981) Interactions of some large organic cations with bentonite in dilute aqueous systems. Clays Clay Miner., 29,205-212.
  12. Pires, J., Carvalho, M.B., Carvalho, A.P., Guil, J.M., and Meln, J.A.P. (2000) Heats of adsorption of n-hexane by thermal gravimetry with differential scanning calorimetry (TG-DSC): A tool for textural characterization of pillared clays. Clays Clay Miner., 48, 385-391.
  13. Sheng, G. and Boyd, S.A. (1998) Relation of water and neutral organic compounds in the interlayers of mixed Ca/trimethylphenylammoniumsmectites. Clays Clay Miner., 46, 10-17.
  14. Sullivan, E.J., Hunter, D.B., and Bowman, R.S. (1997) Topological and thermal properties of surfactant-modified clinoptilolite studied by Tapping-Mode atomic force microscopy and high-resolution thermogravimetric analysis. Clays Clay Miner., 45, 42-53.
  15. Sullivan, E.J., Hunter, D.B., and Bowman, R.S.(1998) Fourier transform Raman spectroscopy of sorbed HDTMA and the mechanism of chromate sorption to surfactant-modified clinoptilolite. Environ. Sci. Techno!., 32, 1948-1995.
  16. Theng, B.K.G. (1974) The chemistry of clayorganic reactions. Adam Hilger, London.
  17. Xu, S. and Boyd, S.A. (1994) Cation exchange chemistry of hexadecyltrimethylammonium in a subsoil containing vermiculite. Soi!. Sci. Soc. Am. J., 58, 1382-1391.
  18. Xu, S. and Boyd, S.A. (1995) Cationic surfactant adsorption by swelling and nonswelling layer silicates. Langmuir, 11, 2508-2514.
  19. Yariv, S. (1985) Study of the adsorption of organic molecules on clay minerals by differential thermal analysis. Thermochim. Acta, 88, 49-68.
  20. Yariv, S., Mueller-Vonmoos, M., Kahr, G., and Rub, A. (1989) Thermal analytic study of the adsorption of crystal violet by montmorillonite. Thermochim. Acta, 148, 457-466.