Modeling of Light Olefin-Paraffin Separation Process Using Supported Liquid Membrane: with Emphasis on Separation of Ethylene-Ethane and Propylene-Propane

Olefin-paraffin separation with equivalent carbon number is an important cost-effective step in olefin production in petrochemical industries. Liquid membrane technology using ionic solutions can perform olefin-paraffin separation in a selective manner. In this paper, the separation of light olefin-paraffin mixtures using supported liquid membrane is modeled in an unsteady-state manner. In this model, mass transfer is considered in the direction of membrane thickness and the effect of feed pressure, silver concentration, solvent type and time on flux rate was investigated. For model evaluation, experimental data of ethylene-ethane separation with aqueous solution of silver nitrate and propylene-propane separation with aqueous solution of silver nitrate, AgNO3-NMP and AgBF4-BMImBF4 were used. There is a good agreement between experimental and modeling data (with 12.2% difference). Moreover, it was concluded that by using viscose or ionic liquids, which are substituted for water (solvent) in order to solve evaporation problems, cause a decrease in flux and product selectivity.