Binary and Ternary Mixtures of Eicosane with Fatty Alcohols and Fatty Acids as Phase Change Material for Building Applications

Abstract

Stable phase change materials (PCMS ) of binary and ternary mixtures of organic compounds were prepared in this work to be installed in buildings for purposes of heat energy storage. Binary mixtures of PCMS as salt hydrates, paraffins were heavily investigated but most of the mixing was within the same group very few articles deal with mixing PCMS from different organic groups or mixing more than two materials. A preparation and a differential scanning calorimetry ( DSC) investigation of binary and ternary mixtures of eicosane with fatty alcohols and fatty acids were performed. The eutectic mixtures of the binary systems were determined to be( 70% eicosane – 30% cetyl alcohol ) , (50% eicosane – 50% lauric acid) and (25% eicosane – 75% capric acid ) with melting temperature and latent heat of ( 33.77 ºC , 237.6 J/g ) , ( 30.63 ºC , 207.7 J/g ) and ( 24.96 ºC , 200.3 J/g ) respectively . The last one is very suitable for building applications. An eutectic mixture of eicosane with myristyl alcohol from previous work was considered as a new material and used to prepare two ternary mixtures( for the first time in literature) with both Cetyl Alcohol and Capric acid . An exciting results of temperatures were obtained : 26.86 ºC for the first ternary mixture and 16.23 ºC for the second one with moderate latent heats of 133.5 J/g and 157.7 J/g. The first one is very suitable for building applications and the second one is suitable for low thermal applications .These results will open the door to try ternary mixtures of common phase change materials to obtain various melting temperatures to suit different applications .