Theoretical Interpretation of the Existence at 40℃ of an Absolute Maximum of the Hydration Rate of Calcium Sulphate Hemi Hydrate under Microwave Irradiation

Abdelhadi Tekkouk, Etienne Karmazsin, Mohamed Laid Samai

Department of Civil Engineering, Mentouri University, Route de Ain El-Bey, Constantine, Algeria.
Université Claude Bernard Lyon I et CPE (Ecole Supérieure de Chimie Physique et Electronique de Lyon), Villeurbanne,Lyon, France.

DOI: 10.4236/ojce.2012.22008                

Abstract

The temperature influence factor on the kinetics of hydration of hemi hydrated calcium sulphate β has been studied in this work under microwave irradiation between 10℃ and 50℃ by isothermal calorimetry. Results show that the temperature corresponding to a maximum of the maximum rate of hydration or a minimum of t_m, the existence of which could be shown theoretically and experimentally during the conventional hydration does not exist under microwave irradiation. This maximum rate or minimum of t_m, is replaced by a limit (above 40℃) which has been determined and interpreted.

Keywords

Microwave; Isothermal Calorimetry; Calcium Sulphate Hemi Hydrate; Kinetics

Conflicts of Interest

The authors declare no conflicts of interest.

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