Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-28T01:08:06.386Z Has data issue: false hasContentIssue false

Heating device for high temperature X-ray powder diffraction studies under controlled water vapour pressure (0–1000 mbar) and gas temperature (20–200 °C)

Published online by Cambridge University Press:  10 January 2013

Martin Oetzel
Affiliation:
Institut für Kristallographie, RWTH Aachen, Jägerstrasse 17-19, D-52066 Aachen, Germany
Franz-Dieter Scherberich
Affiliation:
Institut für Kristallographie, RWTH Aachen, Jägerstrasse 17-19, D-52066 Aachen, Germany
Gernot Heger
Affiliation:
Institut für Kristallographie, RWTH Aachen, Jägerstrasse 17-19, D-52066 Aachen, Germany

Abstract

In this paper we present a high temperature heating device, working under defined environmental conditions, for a Siemens D500 Bragg–Brentano powder diffractometer. The powder sample is prepared in a flat mould on a metal block consisting either of copper or of platinum depending on the temperature range selected for investigations. Although the heating cell can be used separately under ambient conditions up to sample temperatures of 1000 °C, it is possible to work under defined environmental conditions in the temperature range between 20 and 200 °C and up to a water vapour pressure of 1000 mbar. For that purpose a special cover for the in situ control of temperature and water vapour pressure has been constructed. It is important to note that the three sample conditions (sample temperature, gas temperature, and gas humidity) can be adjusted separately by the user. Current studies have shown that the described X-ray heating device is a powerful tool to study dehydration reactions in the frame of fundamental research as well as to understand industrially relevant processes concerning dehydration reactions and their mechanisms.

Type
Technical Articles
Copyright
Copyright © Cambridge University Press 2000

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

Abriel, W. (1983). “Calcium Sulfat Subhydrat. CaSO 4 0.8 H 2O,” Acta Crystallogr., Sect. C: Cryst. Struct. Commun. 39, 956.Google Scholar
Abriel, W. et al. (1990). “Dehydration Reactions of Gypsum: A Neutron and X-ray Diffraction Study,” J. Solid State Chem. 85, 23.CrossRefGoogle Scholar
Allmann, R. et al. (1994). “Das Verhalten von Bassanit bei Variation des äuβeren Wasserdampfpartialdrucks,” Eur. J. Mineral. 6, 3.Google Scholar
Behruzi, C. et al. (1991). “Low- and High-Temperature Accessories for the D500 Powder Diffractometer,” Mater. Sci. Forum 79–82, 433.Google Scholar
Bezou, C. et al. (1990). “Identification Chimique et Radiocristallographique de Deux Formes Sous-hydratées du Sulfate de Calcium: CaSO 4, 0,5 H 2O et CaSO 4, 0,6 H 2O,” C. R. Acad. Sci. ParisSer. II311, 1493.Google Scholar
Bezou, C. et al. (1991). “Structures Cristallines de CaSO 4, 0.5 H 2O et CaSO 4, 0,6 H 2O,” C. R. Acad. Sci. Paris,Ser. II312, 43.Google Scholar
Bezou, C. et al. (1995). “Investigation of the Crystal Structure of γ-CaSO 4, CaSO 4 0.5 H 2O, and CaSO 4 0.6 H 2O by Powder Diffraction Methods,” J. Solid State Chem. 117, 165.CrossRefGoogle Scholar
Bish, D. L. and Reynolds, R. C., Jr. (1989). Modern Powder Diffraction: Sample Preparation for X-ray Diffraction, Reviews in Mineralogy Volume 20 (Mineralogical Society of America, Washington D.C.).Google Scholar
Brooks Instruments GmbH, Haan Office, Rheinische Strasse 2, D-42781 Haan, Germany.Google Scholar
Brown, M. E. (1997). “The Prout–Tompkins Rate Equation in Solid-State Kinetics,” Thermochim. Acta 300, 93.CrossRefGoogle Scholar
Bunn, C. W. (1941). “Some Applications of X-ray Diffraction Methods in Industrial Chemistry,” J. Sci. Instrum. 18, 70.CrossRefGoogle Scholar
Bushuev, N. N. (1982). “Water of Crystallisation in the CaSO 4 0.67 H 2O and CaSO 4 0.5 H 2O Structures,” Russ. J. Inorg. Chem. 27, 344.Google Scholar
Cammenga, H. K.and Epple, M. (1995). “Grundlagen der Thermischen Analysetechniken und ihre Anwendungen in der präparativen Chemie,” Angew. Chem. 107, 1284.CrossRefGoogle Scholar
Carr-Brion, K. (1986). Moisture Sensors in Process Control (Elsevier, London), 122 pp.Google Scholar
Duda, A.and Hilbert, Th. (1989). “Beurteilung Moderner Methoden zur Quantitativen Phasenanalyse von Industriegipsen und daraus erzeugten Bindemitteln,” ZKG 42/8, 425.Google Scholar
Flynn, J. H. (1992). “Thermal Analysis Kinetics—Past, Present, and Future,'Thermal Analysis Kinetics—Past, Present, and Future,'’Thermochim. Acta 203, 519.CrossRefGoogle Scholar
Galwey, A. K.and Brown, M. E. (1997). “Arrhenius Parameters and Compensation Behaviour in Solid-State Decompositions,” Thermochim. Acta 300, 107.CrossRefGoogle Scholar
Greenspan, L. (1977). “Humidity Fixed Points of Binary Saturated Aqueous Solutions,” J. Res. Natl. Bur. Stand., Sect. A 81A, 89.Google Scholar
Hand, R. J. (1997). “Calcium Sulphate Hydrates: A Review,” Br. Ceram. Trans. 96/3, 116.Google Scholar
Hashizume, H. et al. (1996). “An X-ray Diffraction System With Controlled Relative Humidity and Temperature,” Powder Diffr. 11/4, 288.CrossRefGoogle Scholar
Herbstein, F. H. et al. (1982). “X-ray Diffraction as a Tool for Studying Stoichiometry and Kinetics of Solid State Thermal Decomposition Reactions. Applications to the Thermal Decomposition of Bischofite MgCl 2 6H 2O,” Isr. J. Chem. 22, 207.CrossRefGoogle Scholar
Klaue, B.and Dannecker, W. (1994). “Humidity Dependent X-ray Diffraction—A New Way to Investigate Deliquescence Properties of Hygroscopic Salts in Ambient Aerosol Samples,” J. Aerosol Sci. 25, 297.CrossRefGoogle Scholar
Klug, H. P. and Alexander, L. E. (1974). X-ray Diffraction Procedures, 2nd Ed. (Wiley, New York).Google Scholar
Kuzel, H. J.and Hauner, M. (1987). “Chemische und kristallographische Eigenschaften von Calciumsulfat–Halbhydrat und Anhydrit III,” ZKG 12, 628.Google Scholar
Kuzel, H. J.and Kiehne, H. (1969). “Ein einfacher Heizaufsats für Pulverdiffraktometer bis 800 °C,” N. Jb. Miner. Mh. 235, 66.Google Scholar
Oetzel, M. (unpublished).Google Scholar
Oetzel, M. (unpublished).Google Scholar
Rietveld, H. M. (1969). “A Profile Refinement Method for Nuclear and Magnetic Structures,” J. Appl. Crystallogr. 2, 65.CrossRefGoogle Scholar
Rodriguez-Carvajal, (1993). Physica B 192, 55.CrossRefGoogle Scholar
VAISALA Oyj, P. O. Box 26, 00421 Helsinki, Finland, http://www.vaisala.comGoogle Scholar
Zeunert (private communication).Google Scholar