A novel composite phase change material from lauric acid, nano-Cu and attapulgite: Preparation, characterization and thermal conductivity enhancement

Abstract

The utilization of phase change material (PCM) of lauric acid (LA) in thermal energy storage system is limited by liquid phase leakage and relatively low thermal conductivity. Therefore, a novel composite PCM of LA@Cu/Attapulgite was prepared in order to overcome the aforementioned issues. Herein, the nano-Cu were firstly to disperse into LA with different loadings (1, 2, 3 and 4 wt.%,) by ultrasonic dispersion method to form the PCM of LA@Cu. Then, LA@Cu was combined with the supporting material of attapulgite by vacuum impregnation method. The results show that LA@Cu with 2 wt.% of Cu has the best dispersion of Cu with good thermal properties and high thermal conductivity (0.33 W/(m·K)). The composite PCM of LA@Cu/Attapulgite melted/solidified at 42.1 °C/40.6 °C with the melting/solidification latent heat of 87.1 J/g/86.2 J/g, and exhibited good thermal stability and thermal reliability. The thermal conductivity of LA@Cu/Attapulgite reached 0.46 W/(m·K) which was synergistically enhanced by Nano-Cu and attapulgite. The above results indicated that the composite PCM of LA@Cu/Attapulgite have potential application in energy conservation of buildings.