Non-isothermal crystallization kinetics of paraffin wax as a phase changing energy storage material
Amal Louanate, Rabie El Otmani, Khalid Kandoussi, M’hamed Boutaous
Abstract
Abstract Paraffin waxes are becoming increasingly attractive especially on thermal energy storage field. The crystallization process, considered as a major thermal discharging approach, has a significant impact on the thermal performances of paraffin wax. This study aims to comprehend the mechanism of paraffin wax crystallization under non-isothermal conditions by means of Differential Scanning Calorimetry (DSC). Jeziorny and Mo models were applied to reveal the morphology of paraffin wax crystals. Moreover, the non-isothermal crystallization activation energy was calculated through Kissinger and Friedman methods, respectively. Investigations show that the used kinetics models gratifyingly fitted the experimental data, providing crystallization kinetic parameters such as crystallization rate, half-life time (t 1/2 ) as well as the required cooling rate for a designated relative crystallinity. Furthermore, it was found that the average Avrami exponent value is close to 2 which indicates that the crystals are one-dimensional with needle-like morphologies.