Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-30T15:51:53.208Z Has data issue: false hasContentIssue false
  • English
  • Français

Analysis of kaolinite/chrysotile mixtures by ashing and x-ray diffraction

Published online by Cambridge University Press:  05 March 2012

Jennifer R. Verkouteren ,
Eric S. Windsor ,
Joseph M. Conny ,
Robert L. Perkins  and
J. Todd Ennis
Jennifer R. Verkouteren*
Affiliation:
Chemical Science and Technology Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899
Eric S. Windsor
Affiliation:
Chemical Science and Technology Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899
Joseph M. Conny
Affiliation:
Chemical Science and Technology Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899
Robert L. Perkins
Affiliation:
Center for Environmental Measurements and Quality Assurance, Research Triangle Institute, Research Triangle Park, North Carolina 27709
J. Todd Ennis
Affiliation:
Center for Environmental Measurements and Quality Assurance, Research Triangle Institute, Research Triangle Park, North Carolina 27709
*
a)Electronic mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

A simple ashing procedure for a mixture containing kaolinite and chrysotile is described that converts kaolinite to amorphous metakaolinite while retaining the diffraction intensity of chrysotile. This ashing procedure removes the X-ray diffraction (XRD) pattern overlap between kaolinite and chrysotile that can interfere with the analysis of even high concentrations of chrysotile. Samples are ashed at 460 °C in a muffle furnace for 40 h to completely convert kaolinite to metakaolinite. The complete conversion of 1 g of kaolinite under these conditions was determined for two standard kaolinite samples from Georgia, KGa-1 and KGa-2. Two of the most common types of commercial chrysotile, long-fiber Canadian and short-fiber Californian chrysotile, are demonstrated to retain diffraction intensity after ashing at 460 °C. Both chrysotile samples have the same integrated intensity for the (002) reflection prior to ashing, although the peak breadths for the two samples are quite different. Ashing at 480 and 500 °C reduces the diffraction intensities of both chrysotile samples by 15%, and broadens the peaks by approximately 3%. Using the prescribed ashing procedure and x-ray diffraction with an internal corundum standard, two kaolinite-bearing building materials containing chrysotile near 0.01 mass fraction were analyzed. The ashing procedure has additional advantages in reducing some samples to powders and removing volatile components, thereby eliminating some sample preparation procedures and concentrating any chrysotile present in the sample. The removal of volatile components improves the sensitivity of XRD analysis to concentrations below 0.01 mass fraction chrysotile.

Type
Technical Articles
Information
Powder Diffraction , Volume 17 , Issue 3 , September 2002 , pp. 196 - 201
Copyright
Copyright © Cambridge University Press 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

Campbell, W. J., Huggins, C. W., and Wylie, A. G. (1980). Chemical and Physical Characterization of Amosite, Chrysotile, Crocidolite, and Nonfibrous Tremolite for Oral Ingestion Studies by the National Institute of Environmental Sciences, U.S. Bureau of Mines Report of Investigation 8452 (USGPO, Washington, DC), 1980-603-102/41.Google Scholar
De Stefano, L., De Luca, F., Buccolieri, G., and Plescia, P. (2000). “Milling effects upon quantitative determinations of chrysotile asbestos by the reference intensity ratio method,” Powder Diffr. PODIE2 15, 26–29. pdj, PODIE2 CrossRefGoogle Scholar
Djemai, A., Balan, E., Morin, G., Labbe, J. C., and Muller, J. P. (2001). “Behavior of paramagnetic iron during the thermal transformations of kaolinite,” J. Am. Ceram. Soc. JACTAW 84, 1017–1024. jac, JACTAW Google Scholar
Giese, Jr., R. F. (1988). Kaolin Minerals: Structures and Stabilities, in Reviews in Mineralogy Vol. 19, edited by S. W. Bailey (Mineralogical Society of America, Washington D.C.), pp. 29–62.Google Scholar
Gualtieri, A.and Artioli, G. (1995). “Quantitative determination of chrysotile asbestos in bulk materials by combined Rietveld and RIR methods,” Powder Diffr. PODIE2 10, 269–277. pdj, PODIE2 Google Scholar
Gualtieri, A. F., Moen, A., and Nicholson, D. G. (2000). “XANES study of the local environment of iron in natural kaolinites,” Eur. J. Mineral. EJMIER 12, 17–23. eum, EJMIER CrossRefGoogle Scholar
Hodgson, A. A. (1979). Chemistry and Physics of Asbestos, in Asbestos, Properties, Applications, and Hazards Vol. 1, edited by L. Michaels and S. S. Chissik (Wiley, New York), pp. 67–114.Google Scholar
Hu, R., Block, J., Hriljac, J. A., Eylem, C., and Petrakis, L. (1996). “Use of x-ray powder diffraction for determining low levels of chrysotile asbestos in gypsum-based bulk materials: Sample preparation,” Anal. Chem. ANCHAM 68, 3112–3120. anc, ANCHAM CrossRefGoogle Scholar
Jeyaratnam, M.and West, N. G. (1994). “A study of heat-degraded chrysotile, amosite and crocidolite by x-ray diffraction,” Ann. Occup. Hyg. AOHYA3 38, 137–148. aog, AOHYA3 Google Scholar
Khorami, J., Choquette, D., Kimmerl, F. M., and Gallagher, P. K. (1984). “Interpretation of EGA and DTG analyses of chrysotile asbestos,” Thermochim. Acta THACAS 76, 87–96. tha, THACAS CrossRefGoogle Scholar
Klein, C. (1993). Rocks, Minerals, and a Dusty World, in Reviews in Mineralogy Vol. 28, edited by G. D. Guthrie, Jr. and B. T. Mossman (Mineralogical Society of America, Washington D.C.), pp. 7–59.Google Scholar
Lee, S., Kim, Y. J., and Moon, H. (1999). “Phase transformation sequence from kaolinite to mullite investigated by an energy-filtering transmission electron microscope,” J. Am. Ceram. Soc. JACTAW 82, 2841–2848. jac, JACTAW Google Scholar
Mangia, A. (1980). “A new approach to the problem of kaolinite interference in the determination of chrysotile asbestos by means of x-ray diffraction,” Anal. Chim. Acta ACACAM 117, 337–342. acy, ACACAM CrossRefGoogle Scholar
Massart, D. L., Vandeginste, B. G. M., Deming, S. N., Michotte Y., and Kaufman, L. (1988). Chemometrics: A Textbook (Elsevier, Amsterdam), p. 86.Google Scholar
Mumpton, F. A.and Thompson, C. S. (1975). “Mineralogy and origin of the Coalinga asbestos deposit,” Clays Clay Miner. CLCMAB 23, 131–143. cld, CLCMAB Google Scholar
Perkins, R. L. and Harvey, B. W. (1993). “Method for the determination of asbestos in bulk building materials,” U.S. Environmental Protection Agency EPA/600/R-93/116, Office of Research and Development, Washington, DC 20460.Google Scholar
Rickards, A. L.and Badami, D. V. (1971). “Chrysotile asbestos in urban air,” Nature (London) NATUAS 234, 93–94. nat, NATUAS CrossRefGoogle ScholarPubMed
Sánchez-Soto, P. J., del Carmen Jiménez de Haro, M., Pérez-Maqueda, L. A., Varona, I., and Pérez-Rodriquez, J. L. (2000). “Effects of dry grinding on the structural changes of kaolinite powders,” J. Am. Ceram. Soc. JACTAW 83, 1649–1657. jac, JACTAW Google Scholar
U.S. EPA (1982). “Interim method for the determination of asbestos in bulk insulation samples,” U.S. Environmental Protection Agency, 600/M4-82-020.Google Scholar
Veblen, D. R. and Wylie, A. G. (1993). Mineralogy of Amphiboles and 1: 1 Layer Silicates, in Reviews in Mineralogy Vol. 28, edited by G. D. Guthrie, Jr. and B. T. Mossman (Mineralogical Society of America, Washington D.C.), pp. 61–137.Google Scholar
Wicks, F. J. (2000). “Status of the reference x-ray powder-diffraction patterns for the serpentine minerals in the PDF database—1997,” Powder Diffr. PODIE2 15, 42–50. pdj, PODIE2 CrossRefGoogle Scholar
Wicks, F. J. and O’Hanley, D. S. (1988). Serpentine Minerals: Structures and Petrology, in Reviews in Mineralogy Vol. 19, edited by S. W. Bailey (Mineralogical Society of America, Washington D.C.), pp. 91–159.Google Scholar
Wylie, A. G. (1993). “Modeling asbestos populations: A fractal approach,” Can. Mineral. CAMIA6 30, 437–446. can, CAMIA6 Google Scholar