Submitted to: European Journal of Lipid Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 6, 2011
Publication Date: September 8, 2011
Citation: Kenar, J.A. 2012. Thermal characteristics of oleochemical carbonate binary mixtures for potential latent heat storage. European Journal of Lipid Science and Technology. 114:63-70.
Interpretive Summary: This research showed that mixtures of novel biobased materials “oleochemical carbonates” can be used as thermal energy storage (TES) compounds to store and release heat to their surroundings and can potentially be used in applications where a specific temperature is maintained. These carbonate mixtures represent novel renewable-based phase change material (PCM) substances that may provide a potentially valuable biobased alternative to petroleum based paraffin wax PCM and inorganic salt hydrate PCM currently dominating the PCM market. The basic knowledge presented by this research has importance to researchers studying thermal energy storage phenomena, ventures wishing to develop thermal heat storage applications based on biobased compounds, and consumers looking for methods to conserve energy. This work provides new fundamental information about the thermal properties of mixtures of these renewably derived biobased compounds, and showed that these compounds have high thermal energy storage capacities, appropriate phase transition temperatures, and good potential for use as PCM.
The present study examines the thermal properties of melting and solidification for binary mixtures between dodecyl carbonate (1a), tetradecyl carbonate (1b), hexadecyl carbonate (1c), and octadecyl carbonate (1d) by differential scanning calorimetry (DSC) in order to gain further understanding of the solid-liquid transitions in mixtures of these materials. Six combinations of binary carbonate mixtures were examined at various weight fraction ratios and sharp well defined phase transitions were observed at 80:20, 88:12, and 90:10, for (1a:(1b,1c,1d), respectively, at 74:26 and 80:20 for 1b:(1c, 1d), respectively, and at 82.5:17 for 1c:1d. The melting and solidification temperatures for these optimal mixtures ranged between 15-39 oC for melting and 9-33 oC for solidification, respectively. The latent heat of melting and solidification were determined for the eutectic compositions for the binary carbonate mixtures and were found to range between 150-193 J g-1. These carbonate mixtures extend the thermal properties of the pure oleochemical carbonates and compliment other biobased PCM substances such as fatty acids, esters, and alcohols and may provide useful biobased alternatives to paraffin wax and salt hydrate PCM currently dominating the market.