石蜡/改性Al_2O_3相变储能材料的制备与性能研究

PREPARATION AND PROPERTY OF PARAFFINMODIFIED Al_2O_3 COMPOSITES AS PHASE CHANGE ENERGY STORAGE MATERIALS

以石蜡为相变材料、改性Al2O3为载体、无水乙醇为溶剂,采用溶液插层法制备石蜡/改性Al2O3相变储能材料。差示扫描量热(DSC)结果表明PCM-2储能材料的熔化潜热值为142.7 kJ/kg,相变温度为60.9℃;扫描电镜(SEM)和红外(FT-IR)测试表明,吸附后的石蜡与Al2O3载体间具有很强的表面张力,可防止熔化后的石蜡从载体材料中流失;添加少量膨胀石墨后,PCM-2的导热系数从0.389 W/(m·K)提高到2.068 W/(m·K)。连续1000次吸放热试验后,未发现漏液和储热性能明显衰减情况,说明该储能材料具有良好的热稳定性和兼容性。

Paraffin/modified Al2O3 composites as phase change energy storage materials were prepared by solution intercalated reaction. In composite materials, paraffin was used as phase change material （PCM） for thermal energy storage, and modified Al2O3 acted as supporting material, ethanol was the solvent. The performances of the composite materials were analyzed and tested by DSC, SEM and FT-IR. The DSC results show that the PCM-2 composite has the melting latent heat of 142.7 kJ/kg with melting temperature of 60.9 ℃, and the SEM and FT-IR show that the leakage of melted paraffin from the composites can be prevented due to the capillary and surface tension forces between paraffin and Al2O3. By adding some expanded graphite to PCM-2, the thermal conductivity of PCM-2 is increased from 0. 389 W/（m K） to 2. 068 W/（m K） . After one thousand tests for heat absorption and heat release, there are no liquid leakage and heat storage performance attenuation. It shows that the paraffin/ modified Al2O3 composites have a good thermal stability and compatibility.