Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-10T10:05:09.271Z Has data issue: false hasContentIssue false
  • English
  • Français

Reexamination of the Kinetics of the Thermal Desorption of Dimethylsulfoxide and N-Methyl Formamide from a Greensplatt Kaolin

Published online by Cambridge University Press:  02 April 2024

Christopher Breen  and
Sean Lynch
Christopher Breen*
Affiliation:
School of Chemical Sciences, National Institute for Higher Education, Glasnevin, Dublin 9, Ireland
Sean Lynch
Affiliation:
School of Chemical Sciences, National Institute for Higher Education, Glasnevin, Dublin 9, Ireland
*
1Current address: Chemistry Department, Sheffield City Polytechnic, Pond Street, Sheffield S1 1WB, United Kingdom.
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The kinetics of the thermal decomposition of the kaolin: dimethylsulfoxide (kaolin: DMSO) and the kaolin: N-methylformarnide (kaolin: NMF) intercalates have been reexamined. Two different sample sizes (2 mg and 8 mg) and grain-size distributions (<45 μm and 45–63 μm were investigated using isothermal and dynamic gravimetry in the temperature range 100°–200oC. All sample configurations for the kaolin: DMSO intercalate (2 mg, <45 μm; 2 mg, 45–63 μm; 8 mg, <45 μm; 8 mg, 45–63 μm) followed the rate law -ln(1 - α) = kt to a value for α, the reaction fraction complete, of.6, yielding activation energies and standard deviations at the 99% confidence level of 85.5 ± 3.79 and 71.75 ± 8.75 kJ/mole for the isothermal and dynamic runs, respectively. The kaolin: NMF intercalate (2 mg, <45 μm) also followed the same rate law for α <.8, with activation energies and standard deviations at the 99% confidence level of 89 ± 5.05 and 79.25 ± 6.47 kj/mole for the isothermal and dynamic studies, respectively. In solution the rate law -ln(1 - α) = kt is known as first-order kinetics, but here it appears to represent the non-instantaneous nucleation of uniformly sized particles, followed by the inward movement of a reaction interface.

Keywords

Activation energyDesorptionDimethylsulfoxideKaoliniteN-methyl formamideThermal treatment
Type
Research Article
Information
Clays and Clay Minerals , Volume 36 , Issue 1 , February 1988 , pp. 19 - 24
Copyright
Copyright © 1988, The Clay Minerals Society

References

Adams, J. M., 1978 Differential scanning calorimetrie study of the kaolinite: N-methylformamide intercalate Clays & Clay Minerals 26 169 – 172.CrossRefGoogle Scholar
Adams, J. M., 1979 The crystal structure of a dickite: N-methylformamide intercalate Acta Crystallogr. 35 1084 – 1087.CrossRefGoogle Scholar
Adams, J. M. and Waltl, G., 1980 Thermal decomposition of a kaolinite: dimethylsulfoxide intercalate Clays & Clay Minerals! 130 – 133.CrossRefGoogle Scholar
Bradley, R. S., Colvin, J. and Hume, J., 1932 On the mass rate of reactions in solids Proc. Roy. Soc. 137 531 – 541.Google Scholar
Coats, A. W. and Redfern, J. P., 1964 Kinetic parameters from thermogravimetric data Nature 201 66 – 69.CrossRefGoogle Scholar
Costanzo, P. M., Giese, R. F. Jr. and Clemency, C. V., 1984 Synthesis of a 10-Â hydrated kaolinite Clays & Clay Minerals 32 29 – 35.CrossRefGoogle Scholar
Costanzo, P. M., Giese, R. F. Jr. and Lipiscas, M., 1984 Static and dynamic structure in hydrated kaolinites. I. the static structure Clays & Clay Minerals 32 419 – 428.CrossRefGoogle Scholar
Criado, J. M., Ortega, A., Real, C. and Torres de Torres, E., 1984 Reexamination of the kinetics of the thermal de-hydroxylation of kaolinite Clay Miner. 19 653 – 661.CrossRefGoogle Scholar
Delmon, B., 1969 Introduction à la Cinétique Hétérogène Paris Ed. Technip 77 – 79.Google Scholar
Hach-Ali, P. F. and Weiss, A., 1969 Estudio de la reaccion de caolinita y N-metilformamida An. Quim. Soc. Argent. 65 769 – 790.Google Scholar
Hancock, J. D. and Sharp, J. H., 1972 Method of comparing solid-state kinetic data and its applications to the decomposition of kaolinite, bruche and BaC03 J. Amer. Ceram. Soc. 52 199 – 204.Google Scholar
Lahiri, A. K., 1980 The effect of particle size distribution on T.G. Thermochim. Acta 40 289 – 295.CrossRefGoogle Scholar
Riekel, C. and Schöllhorn, R., 1976 A neutron diffraction study on the intercalation of ammonia into tantalum disulfide Mater. Res. Bull. 369 – 376.CrossRefGoogle Scholar
Thompson, J. G., 1985 Interpretation of solid state 13C and 29Si nuclear magnetic resonance spectra of kaolinite intercalates Clays & Clay Minerals 33 173 – 180.CrossRefGoogle Scholar
Thompson, J. G. and Cuff, C., 1985 Crystal structure of kaolinite: dimethylsulfoxide intercalate Clays & Clay Minerals 33 490 – 500.CrossRefGoogle Scholar