(383e) Separation of R-410A Using 1-Ethyl-3-Methylimidazolium Bis(trifluoromethylsulfonyl)Imide Based on Rate-Based Model Simulation with Measured Mixture Properties

Current refrigerants, hydrofluorocarbons (HFCs), are undergoing an 85% phase-down over the next two decades due to their high global warming potential (GWP) as mandated by the American Innovation and Manufacturing (AIM) Act. Millions of kilograms of HFC mixtures are in use in refrigeration systems and must be recycled at the end of life. Due to the azeotropic nature for the majority of HFC mixtures, efficient separation technology is required to break the azeotrope. Extractive distillation with an ionic liquid (IL) as the entrainer has been proposed as a solution and has shown to be effective.

ASPEN Plus simulations have been utilized to assess the feasibility of the process when a specific IL is used as an entrainer, providing optimal operating conditions for extractive distillation to achieve the targeted purity. Rate-based model simulation is known for providing more realistic results than equilibrium models, as equilibrium conditions may not always be attained. However, there are potential drawbacks, such as inadequate measurements for transport properties and underestimating equipment size due to the use of ideal mixing rules in the absence of experimental mixture properties like density and viscosity. In this work, the impact of fitting mixture property models to actual mixture transport properties to improve simulation accuracy will be presented.