在亚热热制冷剂混合物中表面异常的分子起源
Ismail I I Alkhatib1, Carlos G Albà2,3, Yuting Li1
1Research and Innovation Center on CO2 and Hydrogen (RICH Center) and Chemical and Petroleum Engineering Department, Khalifa University of Science and Technology, PO Box 127788, Abu Dhabi, United Arab Emirates.
概括
这项研究揭示了极性制冷剂混合物可以在不形成亚热的情况下表现出无热性行为,这挑战了以前的假设. 这些系统的界面异常来自微妙的分子相互作用,而不是显著的界面丰富.
科学领域:
- 热力学
- 物理化学
- 材料科学
背景情况:
- 对于极性/非极性制冷剂混合物,已知存在异位形成等界面异常.
- 对于仅由极性制冷剂组成的混合物,这种现象尚未得到充分研究.
研究的目的:
- 研究纯制冷剂及其二元混合物的相位平衡和界面特性.
- 确定极性制冷剂混合物中界面异常的分子起源.
- 在含有R134a的混合物中模拟和预测亚热和无热的形成.
主要方法:
- 使用极性软SAFT状态方程.
- 使用密度梯度理论 (DGT) 来建模接口属性.
- 用现有数据对16种纯制冷剂和二元混合物进行了验证.
主要成果:
- 在极性制冷剂混合物中,可以独立于亚热的形成.
- 阳性组合与零相对吸附相关,而不是阳性组合.
- 观察到微妙的偏向吸附,没有明显的界面丰富.
结论:
- 质疑极性制冷剂混合物中无极性类似行为的亚热性.
- 提供了分子层面的洞察力.
- 提供了可持续的下一代制冷剂的设计信息.
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