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OP-II-5SEPARATION OF GASEOUS OLEFIN/PARAFFIN MIXTURES BYREACTIVE ABSORPTION IN A MEMBRANE CONTACTOROrtiz A., Fallanza M., Gorri D., Ortiz I.*Departamento de Ingeniería Química. Universidad de Cantabria. Avda. de losCastros s/n. 39005 Santander, Spain: *e-mail: ortizi@unican.esThe separation of olefins and paraffins is of primary importance in the chemicalindustry. Traditional systems, like low-temperature distillation, are expensive, energyconsumingand voluminous process equipment due to the similarity in boiling point ofolefin and their corresponding paraffin. Therefore, alternative, less-expensiveseparation methods are required. Among a number of alternatives separationprocesses, reactive absorption of olefins from olefin/paraffin mixtures using a silversalt solution as absorption liquid in a gas/liquid membrane contactor may beattractive in this respect.The two main advantages of membrane contactors over conventional two-phasecontacting-based separating devices are their non-dispersive character and their highefficiency in terms of mass transfer, due to increased specific area of contact. Due tothis non-dispersive contact, the flow-rates on both sides of the membrane may be setindependently, as long as the pressure conditions along the contactor module assurethe stabilization of the two-phase interface. Additionally, foaming in gas–liquidseparation processes is minimized. The high efficiency in terms of mass transfer isdue to high (and known) interfacial areas, which lead to more compact equipments.Also, scaling up is easy due to the modular character of the equipment.Solvents with high olefin-capacity, selectivity and resistance to contaminants andprocess conditions are still needed. Room Temperature Ionic liquids (RTILs) can beuse as reactive absorption solvents for olefin/paraffin separations because of its ionicand organic character together with its renowned and remarkable properties. In thiswork, BMImBF 4 has been selected for experiments because of absorption selectivityfor propylene over propane and it is able to dissolve a suitable silver salt (AgBF 4 ),allowing to absorb propylene due to reversible complexation of silver ions withunsaturated olefinic double bonds.In previous works, the physico-chemical characteristics of the system, absorptionequilibrium and kinetics of the reaction between propylene and Ag + -BMImBF 4mixtures, required to design industrial separation processes with gas-liquid106