Comparative study of different typical organic form-stable phase change materials packaged by carbonized wheat straw-expanded graphite binary supporting material

• Published in: Journal of energy storage 2025-02, Vol.108, p.115088, Article 115088
• Main Authors: Liu, Peng, Tan, Zhonghui, Cui, Xinglan, Zhang, Zhikai, Fang, Hui, Li, Haijian, Bian, Liang, Gu, Xiaobin
• Format: Article
• Language: English
• Subjects: Carbonized wheat straw-expanded graphite; FSPCM; Package efficiency; Thermal energy storage property comparisons; Typical organic phase change materials
• ISSN: 2352-152X
• DOI: 10.1016/j.est.2024.115088

This work employed the three organic phase change materials (PCMs), lauric acid (LA), hexadecanol (HD), and paraffin wax (PW) as working media. Carbonized wheat straw (CWS) and expanded graphite (EG) were combined as the supporting material to synthesize novel form-stable PCMs (FSPCMs) through a simple direct impregnation method. The properties of the CWS-EG binary supporting material incorporating the different above-mentioned organic PCMs were investigated. Various characterization methods were used to thoroughly evaluate and compare the performance of the fabricated CWS-EG/PCM FSPCMs with the three different organic PCMs. Results indicated that the PCM loading efficiency was highest in the CWS-EG/HD composite at 55 %, compared to 50 % for CWS-EG/LA and 40 % for CWS-EG/PW. The FSPCM composites maintained good shape stability without leakage. SEM images showed that HD, LA, and PW could be uniformly distributed on the surface and within the gaps of CWS-EG. FTIR analysis confirmed that no chemical reactions occurred among the components of the CWS-EG/PCM FSPCM. DSC results showed that the enthalpy value of phase change was highest for CWS-EG/HD at 162.77 J/g, compared to 105.32 J/g and 85.04 J/g for CWS-EG/LA and CWS-EG/PW, respectively. TGA results revealed that CWS-EG/PCM FSPCM exhibited excellent thermal stability. Additionally, the thermal conductivity of the CWS-EG/PW composite significantly increased to 2.01 W/(m·K), a 615.1 % improvement over pure HD. Compared with pure PCM, the thermal conductivity of the CWS-EG/HD and CWS-EG/LA reached 1.70 and 1.17 W/(m·K), increased by 386.1 % and 502.1 %, respectively. In conclusion, the binary CWS-EG efficiently encapsulated various organic PCMs, with the prepared FSPCMs exhibiting excellent thermal storage properties. CWS-EG shows potential as a supporting material for thermal storage applications. This study not only offers a high-value utilization approach for biomass solid waste but also provides new insights for developing high-performance, low-cost PCMs for thermal energy storage. •Novel eco-friendly CWS-EG/PCM FSPCMs were fabricated by CWS-EG binary supporting material.•A comparative study of the three typical organic FSPCMs packaged by CWS-EG was investigated.•Freezing temperature and enthalpy of CWS-EG/HD FSPCM was 49.14 °C and 162.77 J/g, respectively.•Thermal conductivity of CWS-EG/PW FSPCM was up to 2.01 W/m·k and increased by 615.1 %.