甲基+二甲基酸盐系统的固体-液体相图:应用于低温热能存储的应用
Maria C M Sequeira1, Timur Nikitin2, Fernando J P Caetano3,4
1Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.
概括
本研究详细介绍了二甲基酸盐 (DMA) 和二基酸盐 (DPA) 混合物的固体-液体相图. 这些发现支持它们作为低温热能存储的相变材料的使用.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 热力学是一种热力学.
背景情况:
- 在低温热能储存 (TES) 方面,di-n-alkyl基酸盐显示出作为相变材料 (PCM) 的潜力.
- 之前的研究探讨了二甲基和二甲基酸盐,突出了它们在零度以下温度的PCM能力.
- 了解这些系统中的相位平衡对于优化TES应用至关重要.
研究的目的:
- 为了研究二甲基酸盐 (DMA) +二基酸盐 (DPA) 二元系统的固体-液体相图.
- 为了扩大对di-n-alkyl酸盐低温相位行为的热力学知识.
- 评估DMA+DPA系统作为零度以下TES的PCM系统的潜力.
主要方法:
- 不同扫描热量计 (DSC) 用于相位过渡温度和热量.
- 热阶段显微镜 (HSM) 用于视觉阶段观察.
- 拉曼光谱检测证实非同态的幼虫行为.
主要成果:
- DMA+DPA系统表现出优化行为,优化点在252.83 K,大约是0.77mol的DPA.
- 证实了非同构的欧特克相图,表明不同的晶体结构.
- 液体线被准确地用一个合适的方程 (RMSD = 0.65 K) 建模.
结论:
- 该研究为DMA+DPA二进制系统提供了第一个固体-液体相图.
- DMA+DPA系统展示了低于零度的热能存储应用的潜力.
- 这项研究为开发先进的热能储能技术提供了有价值的数据.
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