Selective separation of HFC-32 from R-410A using poly(dimethylsiloxane) and a copolymer of perfluoro(butenyl vinyl ether) and perfluoro(2,2-dimethyl-1,3-dioxole)

Currently, millions of kilograms HFCs and HFC mixtures are in use with no method for efficiently separating the components. Membranes an attractive refrigerant due to both lower energy consumption capital requirements compared alternative separation methods such as distillation. This study investigates poly(dimethylsiloxane) CyclAFlor™, amorphous copolymer 5 mol% perfluoro(butenyl vinyl ether) 95 perfluoro(2,2-dimethyl-1,3-dioxole), R-410A, azeotropic mixture composed 50 wt% difluoromethane (HFC-32, CH2F2) pentafluoroethane (HFC-125, CHF2CF3). Pure gas permeability HFC-32 HFC-125 were measured using a static membrane apparatus pressure-rise method. Solubility diffusivity gravimetric microbalance. Permeability measurements indicate high selectivity over mixed utilizing excellent agreement ideal calculations based on solubility measurements. Stability studies that plasticization fluorinated polymer is minimal presence HFC-125.