New horizon for the membrane separation: Combination of organophilic and hydrophilic pervaporations

[Display omitted] •The pervaporation is able to remove the isobutanol from an aqueous mixture.•Separation capability of hydrophilic membranes are much better than organophilic.•The improved novel model results in a better fit to the experimental data.•Capital cost of pervaporation unit is the highest part of the total annual cost.•The limiting capital cost is determined by the pervaporators’ membrane areas. The work is motivated by an industrial separation problem, that is, isobutanol removal from aqueous mixture. To complete this goal a hybrid separation system of organophilic–hydrophilic pervaporation system is designed applying Sulzer PERVAP™ 4060 and 1510 membranes and investigated to obtain information about the separation of isobutanol–water mixture. The aim of research is to rigorously model and optimize this novel hybrid process. Permeation fluxes, permeances, selectivities and separation factors are experimentally determined for this hybrid system. The pervaporation separation index (PSI) and selectivity data are compared with those of other membranes published in the literature and it is found that PERVAP™ 4060 has the highest PSI value and its other parameters are also among the best. Our experimental data are evaluated with the pervaporation model of our improvement and it is found that the model can be applied also for both organophilic and hydrophilic pervaporations. The hybrid separation system is rigorously modelled with ChemCAD and optimized with the dynamic programming optimization method. The objective function of the hybrid system is the total annual cost but its energy consumption is also investigated. It can be determined that this hybrid process, that is, the combination of organophilic and hydrophilic pervaporations is capable for the separation of isobutanol and water and it can become the alternative of distillation based separation. Considering our results it can be assumed that the combination of the organophilic and hydrophilic pervaporations opens new horizons for the membrane processes.