Hostname: page-component-7479d7b7d-c9gpj Total loading time: 0 Render date: 2024-07-15T17:58:21.032Z Has data issue: false hasContentIssue false
  • English
  • Français

Identification of halloysite (7 Å) by ethylene glycol solvation: the ‘MacEwan effect’

Published online by Cambridge University Press:  09 July 2018

S. Hillier  and
P. C. Ryan
S. Hillier*
Affiliation:
Macaulay Institute, Craigiebuckler, Aberdeen, AB15 8QH, UK
P. C. Ryan
Affiliation:
Geology Department, Middlebury College, Middlebury, VT 05753 USA
*
*E-mail: s.hillier@macaulay.ac.uk
Get access Rights & Permissions [Opens in a new window]

Abstract

X-ray powder diffraction patterns of halloysite (7 Å) are characteristically altered following solvation with ethylene glycol. Some effect was first noted in the classic work of MacEwan but its value in the unequivocal identification of halloysite (7 Å ) seems to have been overlooked subsequently. The response to ethylene glycol solvation involves a decrease in the intensity (peak height) of the peak at ∼7.2 Å and an increase in the intensity (peak height) of the peak at ∼3.58 Å thus narrowing the 7.2 Å /3.58 Å peak height intensity ratio. For pure samples of halloysite, this ratio is narrowed by an average of ∼50%. This distinctive change is related to the interstratified nature of halloysite (7 Å), specifically the presence of ‘residual’ interlayer water, i.e. halloysite (10 Å), which can be replaced with ethylene glycol so forming 10.9 Å layers, a spacing that is almost exactly one and a half times the thickness of dehydrated (7.2 Å) layers which do not imbibe ethylene glycol. Thus the separation between the 001 peaks in the 7.2 Å /10.9 Å interstratification is increased and the 0027.2 (3.58 Å) and 00310.9 (3.63 Å) peaks become more or less coincident, compared to the 7.2 Å /10 Å interstratification, i.e. the partially hydrated state. The widespread use of ethylene glycol solvation in clay mineral studies makes it a particularly useful and simple test to determine the presence of halloysite. Pure halloysites should be readily identifiable and experiments indicate a ‘routine’ sensitivity of ∼20% halloysite in mixtures with kaolinite, although this will depend on factors such as ‘crystallinity’ and could be improved with careful attention to intensity measurements. It is proposed to call this phenomenon the ‘MacEwan effect’ in honour of its discoverer Douglas Maclean Clark MacEwan.

Keywords

halloysitekaolinitekaolinethylene glycolX-ray powder diffractionMacEwan
Type
Research Article
Information
Clay Minerals , Volume 37 , Issue 3 , September 2002 , pp. 487 - 496
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2002

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bailey, S.W. (1980) Summary of recommendations of AIPEA nomenclature committee. Clays and Clay Minerals, 28, 73–78.Google Scholar
Brindley, G.W. (1951) X-ray Identification and Crystal Structures of Clay Minerals. Pp. 345, Clay Minerals Group, Mineralogical Society, London.Google Scholar
Brindley, G.W. & Brown, G. (1984) Crystal Structures of Clay Minerals and their X-ray Identification. Monograph 5, Mineralogical Society, London, p. 495.Google Scholar
Brindley, G.W. & Goodyear, J. (1948) The transition of halloysite to metahalloysite in relation to relative humidity. Mineralogical Magazine, 28, 407–422.CrossRefGoogle Scholar
Brindley, G.W., Santos, P. Souza, de & Santos, H. Souza, de (1963) Mineralogical studies of kaolinitehalloysite clays. I. Identification problems. American Mineralogist, 48, 897–910.Google Scholar
Churchman, G.J. (1990) Relevance of different intercalation tests for distinguishing halloysite from kaolinite in soils. Clays and Clay Minerals, 38, 591–599.CrossRefGoogle Scholar
Churchman, G.J. & Carr, R.M. (1975) The definition and nomenclatu re of halloysites. Clays and Clay Minerals, 23, 382–388.CrossRefGoogle Scholar
Churchman, G.J. & Theng, B.K.G. (1984) Interaction of halloysites with amides: mineralogical factors affecting complex format ion. Clay Minerals, 19, 161–175.CrossRefGoogle Scholar
Churchman, G.J., Aldridge, L.P. & Carr, R.M. (1972) Relationship between the hydrated and dehydrated states of a halloysite. Clays and Clay Minerals, 20, 241–246.CrossRefGoogle Scholar
Churchman, G.J., Whitton, J.S., Claridge, G.G.C. & Theng, B.K.G. (1984) Intercalation method using formamide for differentiating halloysite from kaolinite. Clays and Clay Minerals, 32, 241–248.CrossRefGoogle Scholar
Costanzo, P.M. & JrGiese, R.F. (1985) Dehydration of synthetic hydrated kaolinites: a model for the dehydration of halloysite (10 Å). Clays and Clay Minerals, 33, 415–423.CrossRefGoogle Scholar
Dixon, J.B. & Weed, S.B. (1989) Minerals in Soil Environments. Soil Science Society of America, Madison Wisconsin, 1244 pp.CrossRefGoogle Scholar
Drever, J.I. (1973) The preparation of oriented clay mineral specimens for X-ray diffraction analysis by a f ilter-membrane pee l technique. American Mineralogist, 58, 553–554.Google Scholar
Giese, R. (1988) Kaolin minerals: structures and stabilities. Pp. 29–66 in. Hydrous Phyllosilicates (exclusive of micas) (Bailey, S.W., editor). Reviews in Mineralogy, 19. Mineralogical Society of America, Washington D.C. CrossRefGoogle Scholar
Giesking, J.E. (1975) Soil Components, Volume 2, Inorganic Components. Springer Verlag, Berlin, 684 pp.Google Scholar
Heddle, Prof. (1882) Mineral s new to Britain. Mineralogical Magazine, 5, A-2.Google Scholar
Kautz, C.Q. & Ryan, P.C. (2001) Formation of multiple halloysitic phases in a neotropical fluvial terrace sequence. Geological Society of America, Abstracts with Programs, 33, A437.Google Scholar
Kretzschmar, R., Ronarge, W.P., Amoozegar, A. & Vepraskas, M.J. (1997) Biotite alteration to halloysite and kaolinite in soil-saprolite profiles developed from mica schist and granite gneiss. Geoderma, 75, 155–170.CrossRefGoogle Scholar
MacEwan, D.M.C. (1946) Halloysite organic complexes. Nature, 157, 157–160.CrossRefGoogle Scholar
MacEwan, D.M.C. (1948) Complexes of clays with organic compounds I. Complex formation between montmorillonite and halloysite and certain organic liquids. Transactions of the Faraday Society, 44, 349–367.CrossRefGoogle Scholar
MacEwan, D.M.C. (1949) Clay mineral complexes with organic liquids. Clay Minerals Bulletin, 3, 44–46.Google Scholar
Merriman, R.J. & Kemp, S.J. (1995) Mineralogical and microtextural analysis of altered tuffs associated with landslips in Hong Kong. British Geological Survey Technical Report, WG/95/30C.Google Scholar
Miller, W.D. & Keller, W.D. (1963) Differentiation between endellite-halloysite and kaolinite by treatment with potassium acetate and ethylene glycol. Clays and Clay Minerals, 10, 244–253.CrossRefGoogle Scholar
Moore, D.M. & Jr.Reynolds, R.C. (1997) X-ray Diffraction and the Identification and Analysis of Clay Minerals. Oxford University Press, New York, 378 pp.Google Scholar
Plançon, A. & Drits, V.A. (1999) Programs for the calculation of diffraction by oriented powders of two- and three-component mixed-layer clay minerals. http://www.univ-orleans.fr/ ESEM/plancon/ Google Scholar
Range, K.J., Range, A. & Weiss, A. (1969) Fire-clay type kaolinite or fire clay minerals? Experimental classification of kaolinite-halloysite minerals. Proceedings of the International Clay Conference, Tokyo, 3–13.Google Scholar
Singer, A. (1993) Weathering patterns in representative soils of Guanxi Province, south-east China, as indicated by detailed clay mineralogy. Journal of Soil Science, 44, 173–188.CrossRefGoogle Scholar
Theng, B.K.G, Churchman, G.J., Whitton, J.S. & Claridge, G.G.C. (1984) Comparison of intercalation methods for differentiating halloysite from kaolinite. Clays and Clay Minerals, 32, 249–258.CrossRefGoogle Scholar
Wada, K. (1961) Lattice expansion of kaolin minerals by treatment with potassi um acetate. American Mineralogist, 46, 78–91.Google Scholar