Preparation of erythritol-graphite foam phase change composite with enhanced thermal conductivity for thermal energy storage applications

摘要

Three-dimensional interconnected graphite composite foam as a heat conductive matrix was fabricated by using low cost polymeric precursors and polyurethane (PU) foam as carbon source and sacrificial macroporous template, respectively. Erythritol-graphite foam as a stable composite phase change material (PCM) was obtained by incipient wetness impregnation method. The thermophysical properties such as thermal diffusivity, specific heat, thermal conductivity and latent heat of the erythritol-graphite composite foam were measured. From the results, it was found that the thermal conductivity of the erythritol-graphite composite foam (3.77 W/mK) was enhanced 5 times as compared with that of pristine erythritol (0.72 W/mK). This enhancement can significantly reduce the charging and discharging times of the PCM storage system. There is no chemical reaction between erythritol and graphite as confirmed by X-ray diffractometer (XRD). The PCM/foam composite has a melting point of 118 degrees C and latent heat of 251 J/g which corresponds to the mass percentage (75 wt.%) of the erythritol within the composite foam. The obtained results confirmed the feasibility of using erythritol-graphite foam as a new phase change composite for thermal energy storage (TES) applications, thus it can contribute to the efficient utilization and recovery of solar heat or industrial waste heat. (C) 2015 Elsevier Ltd. All rights reserved.