Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-05T10:12:42.081Z Has data issue: false hasContentIssue false

Carbonate-cancrinite: In-situ real-time thermal processes studied by means of energy-dispersive X-ray powder-diffractometry

Published online by Cambridge University Press:  10 January 2013

P. Ballirano
Affiliation:
Dipartimento di Scienze della Terra, Università di Roma La Sapienza, P.le Aldo Moro 5, I-00185, Roma, Italy
A. Maras
Affiliation:
Dipartimento di Scienze della Terra, Università di Roma La Sapienza, P.le Aldo Moro 5, I-00185, Roma, Italy
R. Caminiti
Affiliation:
Dipartimento di Chimica, Università di Roma La Sapienza, P.le Aldo Moro 5, I-00185, Roma, Italy
C. Sadun
Affiliation:
Dipartimento di Chimica, Università di Roma La Sapienza, P.le Aldo Moro 5, I-00185, Roma, Italy

Abstract

New powder X-ray data for cancrinite [ideally Na8Si6Al6O24 (CO3)2·2 H2O] are reported along with in-situ real-time thermal processes recorded using energy dispersive X-ray diffractometry (EDXD). A completely anhydrous phase is obtained after heating the sample up to 600 °C and quickly cooling it to room temperature, as shown by means of both Rietveld analysis and IR spectroscopy. The anhydrous phase does not show any tendency to re-acquire molecular water. During the heating process, at around 450 °C, a peak splitting is observed, possibly due to a reversible phase transition.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1995

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

Appleman, D.E., and Evans, H.T. Jr., (1973). “Indexing and least-squares refinement of powder diffraction data,” U.S. Nat. Tech. Inf. Serv. Doc. PB216188 8, 432435.Google Scholar
Ballirano, P., Maras, A., and Burragato, F. (1991). “Sodalite from Vetralla (Roman potassic province) and Bancroft (Ontario, Canada): observed and simulated IR spectra,” Rend. Fis. Acc. Lincei, Ser. 9, Vol. 2, 361369.CrossRefGoogle Scholar
Belokoneva, E.L., Uvarova, T.G., and Dem'yanets, L.N. (1986). “Crystal structure of synthetic Ge-cancrinite Na8[Al6Ge6O29]Ge(OH)6·2H2O,” Sov. Phys. Crystallogr., 31, 516519.Google Scholar
Benoit, P.H. (1987). “Adaptation to microcomputer of the Appleman-Evans program for indexing and least-squares refinement of powder diffraction data for unit-cell dimensions,” Am. Mineral., 72, 10181019.Google Scholar
Bonaccorsi, E. (1993). “Feldspathoids belonging to the davyne group: crystal chemistry, phase transitions and ionic exchanges,” Plinius, 9, 1622.Google Scholar
Caminiti, R. (1992). “Energy dispersive diffraction of amorphous compounds” (in Italian), XXI Congr. Naz. A.I.C., L'Aquila, Program and abstracts, 76. Patent RMA000410/93.Google Scholar
Grundy, H.D., and Hassan, I. (1982). “The crystal structure of a carbonaterich cancrinite,” Can. Mineral., 20, 239251.Google Scholar
Emiraliev, A., and Yamzin, I.I. (1982). “Neutron-diffraction refinement of the structure of carbonate-cancrinite,” Sov. Phys. Cristallogr., 27, 2730.Google Scholar
Foit, F.F., Peacor, D.R., and Heinrich, E.W. (1973). “Cancrinite with a new superstructure from Bancroft, Ontario,” Can. Mineral., 11, 940951.Google Scholar
Hassan, I., and Buseck, P.R. (1992). “The origin of the superstructure and modulations in cancrinite,” Can. Mineral., 22, 341349.Google Scholar
Jarchow, O. (1965). “Atomanordnung und Strukturverfeinerung von Cancrinit,” Z. Krist. 122, 407422.CrossRefGoogle Scholar
Maras, X., and Balirano, P. (1995).Google Scholar
Nakamoto, K., Margoshes, M., and Rundle, R.E. (1955). “Stretching frequencies as a function of distances in hydrogen bond,” J. Am. Chem. Soc., 77, 64806488.CrossRefGoogle Scholar
Norby, P., Krogh Andersen, I.G., Krogh Andersen, E., Colella, C., and de Gennaro, M. (1991). “Synthesis and structure of lithium cesium and lithium thallium cancrinites,” Zeolites, 11, 248253.CrossRefGoogle Scholar
Smith, G.S., and Snyder, R.L. (1979). “F N: A criterion for rating powder diffraction patterns and evaluating the reliability of powder-pattern indexing,” J. Appl. Cryst., 12, 60.CrossRefGoogle Scholar
Smolin, Yu.I., Shepelev, Yu.F., Butikova, I.K., and Kobyakov, I.B. (1981). “Crystal structure of cancrinite,” Sov. Phys. Cristallogr., 26, 3335.Google Scholar
Sosedko, T.A., Kasatov, B.K., Furmakova, L.N., and Lipatova, Z.A. (1989). “New data on cancrinite-vishnevite mineral-group” (in Russian), Zap. Vses. Mineral. Obsh., 1989, 7884.Google Scholar
Wiles, D.B., and Young, R.A. (1981). “A new computer program for Rietveld analysis of X-ray powder diffraction patterns,” J. Appl. Cryst., 14, 149151.CrossRefGoogle Scholar
Wolff, P.M. de (1968). “A simplified criterion for the reliability of a powder pattern indexing,” J. Appl. Cryst. 1, 108.CrossRefGoogle Scholar