This review discusses the research being performed on ionic liquids for the separation of fluorocarbon refrigerant mixtures. Fluorocarbon refrigerants, invented in 1928 by Thomas Midgley Jr., are a unique class of working fluids that are used in a variety of applications including refrigeration. Fluorocarbon refrigerants can be categorized into four generations: chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, and hydrofluoroolefins. Each generation of refrigerants solved a key problem from the previous generation; however, each new generation has relied on more complex mixtures that are often zeotropic, near azeotropic, or azeotropic. The complexity of the refrigerants used and the fact that many refrigerants form azeotropes when mixed makes handling the refrigerants at end of life extremely difficult. Today, less than 3% of refrigerants that enter the market are recycled. This is due to a lack of technology in the refrigerant reclaim market that would allow for these complex, azeotropic refrigerant mixtures to be separated into their components in order to be effectively reused, recycled, and if needed repurposed. As the market for recovering and reclaiming refrigerants continues to grow, there is a strong need for separation technology. Ionic liquids show promise for separating azeotropic refrigerant mixtures as an entrainer in extractive distillation process. Ionic liquids have been investigated with refrigerants for this application since the early 2000s. This review will provide a comprehensive summary of the physical property measurements, equations of state modeling, molecular simulations, separation techniques, and unique materials unitizing ionic liquids for the development of an ionic-liquid-based separation process for azeotropic refrigerant mixtures.

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用于分离氟碳制冷剂混合物的离子液体

本综述讨论了用于分离碳氟化合物制冷剂混合物的离子液体的研究。碳氟制冷剂由 Thomas Midgley Jr. 于 1928 年发明，是一类独特的工作流体，可用于包括制冷在内的多种应用。氟碳制冷剂可分为四代：氯氟碳、氢氯氟碳、氢氟碳和氢氟烯烃。每一代制冷剂都解决了上一代的一个关键问题；然而，每一代新产品都依赖于更复杂的混合物，这些混合物通常是非共沸、近共沸或共沸的。所使用的制冷剂的复杂性以及许多制冷剂在混合时形成共沸物的事实使得在寿命结束时处理制冷剂极其困难。如今，进入市场的制冷剂中只有不到 3% 被回收利用。这是由于制冷剂回收市场缺乏技术，无法将这些复杂的共沸制冷剂混合物分离成其组分，以便有效地再利用、回收，并在需要时重新利用。随着回收和回收制冷剂的市场不断增长，对分离技术的需求非常强烈。离子液体作为萃取蒸馏过程中的夹带剂，有望分离共沸制冷剂混合物。自 2000 年代初以来，人们一直在研究离子液体与制冷剂的这种应用。本综述将全面总结物理性质测量、状态建模方程、分子模拟、分离技术和结合离子液体的独特材料，以开发基于离子液体的共沸制冷剂混合物分离工艺。