Preparation of Polymer Inclusion Membranes (PIMs) with Ionic Liquid and its Application in Dye Adsorption Process Supported by Statistical Analysis

Polymer inclusion membranes (PIMs) were prepared via Non-Solvent Induced Phase Separation (NIPS) using polyethersulfone (PES) loaded with a liquid ionic, 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]). Hydrophilic porous PIMs with a controlled morphology were obtained and tested for the removal of reactive blue 19 (RB19) as a model anionic dye. The dye adsorption efficiency depends on several variables i.e. pH, contact time, initial dye concentration, amount and weight of adsorbent (PIMs). The optimal values of these parameters were calculated by the multivariate approach of "Experimental design" and, in particular, a central composite design (CCD). The optimal conditions obtained from the response surface data are: [BMIM][PF6] concentration 10.7wt%, pH 3.0, RB19 dye concentration 10.0 ppm and PIMs of weight 0.055 mg. The experimental adsorption percentage of RB19value (69.2%) was in agreement to those predicted by the CCD model (71.7%).