Preparation and Performance Analysis of a Calcium Chloride Hexahydrate–Acetamide/Diatomite Composite Phase Change Material for Thermal Insulation in Low‐Temperature Grain Warehouses
Chuqi Huang, Hao Peng, Yutao Chen, Wanwan Fu, Jiesheng Liu, Man Zhang, Xuemei Wang, Siyuan XiangABSTRACT
To address the high energy consumption issue of low‐temperature grain storage facilities, this study developed a stable composite phase change material (CPCM) through physical mixing. Calcium chloride hexahydrate (CCH) was used as the matrix, acetamide (ACAM) as the temperature regulator, barium carbonate (BaCO 3 ) as the nucleating agent, and diatomite (DE) as the porous support. The mass fractions of the components were systematically optimized. The optimal CPCM (6% ACAM, 2% BaCO 3 , 55% DE) has a phase change temperature of 16.3°C, an enthalpy of 50.49 J/g, a low supercooling degree of 2.2°C, excellent shape stability, and a thermal conductivity of 0.7522 W·m −1 ·K −1 . Comprehensive characterization (SEM, BET, FT‐IR, and XRD) confirmed the successful physical encapsulation of the PCM in diatomite. After 200 thermal cycles, this material demonstrated excellent thermal reliability, with minimal enthalpy loss (<1.6%), stable chemical structure, and showed great potential for energy‐saving insulation in grain storage.