Na2CO3?10H2O-Na2HPO4.12H2O/SiO2复合定形相变材料的制备及应用研究

Preparation and Application Study of Na2CO3?10H2O,-Na2HPO4.12H2O/SiO2 composite shape-stabled Phase Change Materials

摘要:

以十水合碳酸钠(SCD)、十二水合磷酸氢二钠(DHPD)为相变主体,制备了低过冷度,无相分离的共晶水合盐(EHS),以九水合硅酸钠为成核剂。进一步使用气相SiO₂为支撑材料,采用浸渍法制备了相变前后形状稳定的 EHS/SiO₂定形相变储能材料(SSPCM)。所得SSPCM的相变温度为 24.08 ℃,焓值为 146.6 J/g,过冷度为 0.55 ℃,热导率为 0.5454 W/m?K。同保温泡沫相比,其可将模拟房内部中心温度的升温时间延长 3.26 倍,降温时间延长 1.39 倍,具有优异的“热缓冲”性能,在建筑节能领域具有广阔的应用前景。

Abstract:

A eutectic hydrate salt (EHS) with low supercooling degree and no phase separation was prepared using decahydrate sodium carbonate (SCD) and dodecahydrate sodium hydrogen phosphate (DHPD) as the main phase-change materials. Adding nonahydrate sodium silicate as a nucleating agent. A shape-stabled phase-change material (SSPCM) of the fixed EHS/SiO₂ was prepared by adsorbing EHS on gas-phase SiO₂ with impregnation method. The transition temperature of SSPCM was 24.08 ℃, the enthalpy value was 146.6 J/g, the supercooling degree was 0.55 ℃ and the thermal conductivity was 0.5454 W/m?K. Compared with insulation foam, the SSPCM extended the warming time of the central temperature in the building by 3.26 times and the cooling time by 1.39 times, showing excellent"thermal buffering", which have broad application prospects in building energy efficiency.