Enhanced thermal properties of stearic acid/carbonized maize straw composite phase change material for thermal energy storage in buildings. (April 2021)

• Record Type: Journal Article
• Authors: Wen, Ruilong; Liu, Yifeng; Yang, Chen; Zhu, Xiao; Huang, Zhaohui; Zhang, Xianmei; Gao, Wei
• Is Part Of: Journal of energy storage. Volume 36(2021)
• Publication Date: 2021-04
• Subjects: Stearic acid -- Carbonized maize straw -- Form-stable PCM -- Thermal energy storage -- Thermal conductivities; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2021.102420
• Languages: English
• ISSNs: 2352-152X

Abstract

Highlights: The CPCM of SA/CMS has been successful prepared by vacuum impregnation method. The maximum loading capacity of SA/CMS reached 77.22%. The thermal conductivity of SA/CMS was enhanced which reached 0.30 W/(mK) −1 . Abstract: The application of organic phase change material (PCM) using in thermal energy storage system was limited by low thermal conductivity and leakage problem. In this paper, we reported a low-cost supporting material with good thermal conductivity by carboning the biomass of maize straw. The composite PCM of stearic acid (SA)/carbonized maize straw (CMS) was prepared via vacuum impregnation process and characterized by XRD, FT-IR, SEM. The results show that SA/CMS has good chemical compatibility. DSC, TGA as well as thermal conductivity and thermal history method were used to evaluate the thermal properties of SA/CMS. The DSC result reveals that the composite SA/CMS melted at 67.62°C with the latent heat of 160.74 J/g and freezed at 65.28°C with the latent heat of 160.47 J/g. The maximum loading capacity of SA in composite of SA/CMS reached 77.22%. TGA and DTG results show SA/CMS have good thermal stability. Thermal conductivity of SA/CMS reached 0.30 W/(mK), which was 87.5% higher than that of the pure SA. Compared with SA, the melting time of SA/CMS reduced 50% and the freezing time reduced 73%. 200 thermal cycling test shows the SA/CMS exhibits excellent thermal reliability. Based on all results, it can be expected that the form-stable composite PCM of SA/CMS has good potential application in solar heat energy storage system and energy-efficient buildings.