Skip to main content
SpringerLink
Log in

Non-isothermal kinetic and thermodynamic study for the dehydration of copper(II) chloride dihydrate and nickel chloride hexahydrate

  • Published:
Journal of Thermal Analysis Aims and scope Submit manuscript

Abstract

Non-isothermal dehydration of copper chloride dihydrate and nickel chloride hexahydrate were studied by using TG, DTG, DTA and DSC measurements. The copper chloride salt loses its two water molecules in one step while nickel chloride salt dehydrates in three consecutive steps. The first two steps involve the loss of 4 water molecules in two overlapped steps while the third step involves the dehydration of the dihydrate salt to give the anhydrous NiCl2.

Activation energies (ΔE) and the frequency factor (A) were calculated from DTG and DTA results. We have also calculated the different thermodynamic parameters, e.g. enthalpy change (ΔH), heat capacity (C p) and the entropy change (ΔS) from DSC measurements for both reactants.

The isothermal rehydration of the completely dehydrated salts was studied in air and under saturated vapour pressure of water. Anhydrous nickel chloride was found to rehydrate in three consecutive steps while the copper salt rehydrated in one step.

Zusammenfassung

Mittels TG-, DTG-, DTA- und DSC-Messungen wurde die nichtisothermische Dehydratation von Kupferchlorid-Dihydrat und Nickelchlorid-Hexahydrat untersucht. Das Kupferchloridsalz setzt seine zwei Moleküle Wasser in einem Schritt frei, das Nickelchloridsalz dagegen in drei aufeinanderfolgenden Schritten. Davon umfassen die ersten zwei Schritte die Freisetzung von 4 Molekülen Wasser in zwei überlappenden Schritten, während der dritte Schritt vom Dihydratsalz zur Formung von wasserfreiem NiCl2 führt.

Die Aktivierungsenergien (ΔE) und der Frequenzfaktor (A) wurden anhand von DTG- und DTA-Ergebnissen berechnet. Weiterhin berechneten wir anhand von DSC-Messungen auch thermodynamische Parameter, wie z.B. die Enthalpiedifferenz (ΔH), die Wärmekapazität (C p ) und die Entropiedifferenz (ΔS) für beide Reaktanden.

In Luft und bei Sättigungsdampfdruck für Wasser wurde die isotherme Rehydratation der vollständig dehydratierten Salze untersucht. Wasserfreies Nickelchlorid rehydratiert in drei aufeinanderfolgenden Schritten, das Kupfersalz dagegen rehydratiert nur in einem Schritt.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. M. E. Brown, D. Dollimore and A. K. Galwey, Comprehensive Chemical Kinetics, (Ed. C. H. Bamford and C. F. H. Tipper), Elsevier, Amsterdam 1980, Vol. 22.

    Google Scholar 

  2. M. E. Brown, H. Kelly, A. K. Galwey and M. A. Mohamed, Thermochim. Acta, 127 (1988) 139.

    Article  CAS  Google Scholar 

  3. A. K. Galwey, M. A. Mohamed, S. Rajam and M. E. Brown, J. Chem. Soc. Faraday Trans. I, 84 (1988) 1349.

    Article  CAS  Google Scholar 

  4. R. E. Grim, Clay Mineralogy, 2nd ed., McGraw-Hill, New York 1968.

    Google Scholar 

  5. D. Dollimore, Selected Annual Reviews of the Analytical Sciences, 2, 1 (L. S. Bark, Ed.), 1973 (Soc. Anal. Chem.).

  6. D. Dollimore and D. L. Griffiths, J. Thermal Anal., 2 (1970) 229.

    Article  CAS  Google Scholar 

  7. S. Bretsznaider and Z. Roikowski, Bull. Acad. Pol. Sci. Chim., 17 (1969) 139.

    Google Scholar 

  8. A. K. Galwey and M. A. Mohamed, Thermochim. Acta, 121 (1987) 97.

    Article  CAS  Google Scholar 

  9. A. K. Galwey, R. Spinicci and G. G. T. Guarini, Proc. R. Soc. London, Ser. A, 378 (1981) 477.

    Article  CAS  Google Scholar 

  10. A. K. Galwey, R. Reed and G. G. T. Guarini, Nature (London), 283 (1980) 52.

    Article  CAS  Google Scholar 

  11. R. K. Osterheld and P. R. Bloom, J. Phys. Chem., 82 (1978) 1591.

    Article  CAS  Google Scholar 

  12. D. Petzold and T. Naumann, J. Thermal Anal., 20 (1981) 71.

    Article  CAS  Google Scholar 

  13. A. K. Galwey and G. M. Laverty, Thermochim. Acta, 138 (1989) 115.

    Article  CAS  Google Scholar 

  14. M. A. Mohamed and S. A. Halawy, Bull. Fac. Sci., Assiut Univ., 19(2-B), (1990) 107.

    CAS  Google Scholar 

  15. R. C. Weast (Ed.), Handbook of Chemistry and Physics, (62nd ed.) CRC Press, New York 1982.

    Google Scholar 

  16. M. A. Mohamed, S. A. A. Mansour and M. I. Zaki, Thermochim. Acta 138 (1989) 309.

    Article  CAS  Google Scholar 

  17. J. W. Dodd and K. H. Tonge, Thermal Methods, Analytical Chemistry by Open Learning, J. Wiley, New York 1987.

    Google Scholar 

  18. C. Heald and A. C. K. Smith, Applied Physical Chemistry, Macmillan Press Ltd., London 1982, pp. 20–40.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Chemistry, Faculty of Science, Qena, Egypt

    M. A. Mohamed & S. A. Halawy

Authors
  1. M. A. Mohamed
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. S. A. Halawy
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Mohamed, M.A., Halawy, S.A. Non-isothermal kinetic and thermodynamic study for the dehydration of copper(II) chloride dihydrate and nickel chloride hexahydrate. Journal of Thermal Analysis 41, 147–159 (1994). https://doi.org/10.1007/BF02547020

Download citation

  • Received:

  • Revised:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02547020

Keywords

Search

Navigation