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Propylene, commonly with ethylene, builds the backbone of the petrochemical sector.Polypropylene production consumes a huge chunk of propylene capacity, however, there are other important propylene-based chemicals including oxo-alcohols, propylene oxide,acrylonitrile, cumene, polystyrene, etc.Production of propylene and propane rely upon steam cracking gas bay cryogenic distillation in the industry; this process entails high requirements for equipment, cost, and high energy.Ionic liquids have low volatile and good solubility and are therefore considered an ideal alternative compared to traditional solvents, which are organic and which reduce solvent loss and environmental pollution.Also, transition metals have excellent absorption capacity for olefins, and are usually used in the separation of olefin and paraffin along with ionic liquids.The goal from this research to develop absorption of these ionic liquids [Bmim]SCN and [Emim]SCN. The subject, content, and results are organized are summarized as follows: 1) In this article, ten types of ionic liquids with varying Cu+ concentration and DMF are synthesized.The ionic liquids are: [Bmim]SCN-DMF-CuSCN (0M, 0.5M, 1M, 1.5M,2M) and [Emim]SCN-DMF-CuSCN (0M,0.5M, 1M, 1.5M, 2M), which are used temperatures of 298K, 308K, 318K and an applied pressure of 1～7 bar for the absorption and separation of propylene and propane.Furthermore, Cu+ concentration,pressure, temperature, and the ionic liquid cation are also investigated. 2) The results indicate an increase in the absorption of propylene and propane by enhancing the Cu+ concentration, the length of the ionic liquid cation and pressure, decreasing with the enhancing of temperature.Moreover, use DMF in ionic liquids has reduced the viscosity but clearly Increased the absorption for propylene and propane. 3) At 298K, the maximum absorption of propylene and propane moles of Cu+ concentration is 2M.The absorption ofpropylene/propane follows [Emim]SCN-DMF-CuSCN＜[Bmim]SCN-DMF-CuSCN, while the selectivity follows [Bmim]SCN-DMF-CuSCN＜[Emim] SCN-DMF-CuSCN. 4) Ionic liquids used for the separation of a mixture of propylene and propane, ranges between 50％ to 80％ at 298K and with a pressure of 2～4 bar. 5) The results indicate that the selectivity of the mixture of propylene and propane rises with the rise in Cu+ concentration while reducing the ionic liquid cation. 6) Gas mixtures with a higher mole fraction ofpropylene can reach higher absorption and selectivity.The selectivity of the mixture of propylene and propane in [Bmim]SCN-DMF-CuSCN-2M is as high as 55 for a 80 mol％ propylene mixture with propane at 298K and pressure of 2 bar.