Abstract
The reaction process of the thermal dehydration of dilithium tetraborate trihydrate, Li2B4O7⋅3H2O, was reinvestigated from a viewpoint of reaction kinetics. On the basis of the results of thermogravimetry, constant rate thermal analysis, powder X-ray diffractometry, infrared spectroscopy and scanning electron microscopy, it was confirmed that the reaction proceeds via three consecutive kinetic steps characterized by different activation energies. The first and second kinetic steps, accompanied by the destruction of the original crystal structure of the reactant, seem to be assigned to the surface and internal reactions, respectively. During the third kinetic step, the thermal dehydration of hydrated amorphous intermediate, produced at the second kinetic step, and crystallization of the final dehydration product, Li2B4O7, are likely to take place concurrently.
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Koga, N., Criado, J.M. & Tanaka, H. A Kinetic Aspect of the Thermal Dehydration of Dilithium Tetraborate Trihydrate. Journal of Thermal Analysis and Calorimetry 67, 153–161 (2002). https://doi.org/10.1023/A:1013702400974
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DOI: https://doi.org/10.1023/A:1013702400974